diff options
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 5835 |
1 files changed, 5835 insertions, 0 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c new file mode 100644 index 00000000..20219ef5 --- /dev/null +++ b/security/selinux/hooks.c @@ -0,0 +1,5835 @@ +/* + * NSA Security-Enhanced Linux (SELinux) security module + * + * This file contains the SELinux hook function implementations. + * + * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> + * Chris Vance, <cvance@nai.com> + * Wayne Salamon, <wsalamon@nai.com> + * James Morris <jmorris@redhat.com> + * + * Copyright (C) 2001,2002 Networks Associates Technology, Inc. + * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> + * Eric Paris <eparis@redhat.com> + * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. + * <dgoeddel@trustedcs.com> + * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. + * Paul Moore <paul.moore@hp.com> + * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. + * Yuichi Nakamura <ynakam@hitachisoft.jp> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2, + * as published by the Free Software Foundation. + */ + +#include <linux/init.h> +#include <linux/kd.h> +#include <linux/kernel.h> +#include <linux/tracehook.h> +#include <linux/errno.h> +#include <linux/ext2_fs.h> +#include <linux/sched.h> +#include <linux/security.h> +#include <linux/xattr.h> +#include <linux/capability.h> +#include <linux/unistd.h> +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/slab.h> +#include <linux/pagemap.h> +#include <linux/proc_fs.h> +#include <linux/swap.h> +#include <linux/spinlock.h> +#include <linux/syscalls.h> +#include <linux/dcache.h> +#include <linux/file.h> +#include <linux/fdtable.h> +#include <linux/namei.h> +#include <linux/mount.h> +#include <linux/netfilter_ipv4.h> +#include <linux/netfilter_ipv6.h> +#include <linux/tty.h> +#include <net/icmp.h> +#include <net/ip.h> /* for local_port_range[] */ +#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ +#include <net/net_namespace.h> +#include <net/netlabel.h> +#include <linux/uaccess.h> +#include <asm/ioctls.h> +#include <asm/atomic.h> +#include <linux/bitops.h> +#include <linux/interrupt.h> +#include <linux/netdevice.h> /* for network interface checks */ +#include <linux/netlink.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/dccp.h> +#include <linux/quota.h> +#include <linux/un.h> /* for Unix socket types */ +#include <net/af_unix.h> /* for Unix socket types */ +#include <linux/parser.h> +#include <linux/nfs_mount.h> +#include <net/ipv6.h> +#include <linux/hugetlb.h> +#include <linux/personality.h> +#include <linux/audit.h> +#include <linux/string.h> +#include <linux/selinux.h> +#include <linux/mutex.h> +#include <linux/posix-timers.h> +#include <linux/syslog.h> +#include <linux/user_namespace.h> + +#include "avc.h" +#include "objsec.h" +#include "netif.h" +#include "netnode.h" +#include "netport.h" +#include "xfrm.h" +#include "netlabel.h" +#include "audit.h" + +#define NUM_SEL_MNT_OPTS 5 + +extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); +extern struct security_operations *security_ops; + +/* SECMARK reference count */ +atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); + +#ifdef CONFIG_SECURITY_SELINUX_DEVELOP +int selinux_enforcing; + +static int __init enforcing_setup(char *str) +{ + unsigned long enforcing; + if (!strict_strtoul(str, 0, &enforcing)) + selinux_enforcing = enforcing ? 1 : 0; + return 1; +} +__setup("enforcing=", enforcing_setup); +#endif + +#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM +int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; + +static int __init selinux_enabled_setup(char *str) +{ + unsigned long enabled; + if (!strict_strtoul(str, 0, &enabled)) + selinux_enabled = enabled ? 1 : 0; + return 1; +} +__setup("selinux=", selinux_enabled_setup); +#else +int selinux_enabled = 1; +#endif + +static struct kmem_cache *sel_inode_cache; + +/** + * selinux_secmark_enabled - Check to see if SECMARK is currently enabled + * + * Description: + * This function checks the SECMARK reference counter to see if any SECMARK + * targets are currently configured, if the reference counter is greater than + * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is + * enabled, false (0) if SECMARK is disabled. + * + */ +static int selinux_secmark_enabled(void) +{ + return (atomic_read(&selinux_secmark_refcount) > 0); +} + +/* + * initialise the security for the init task + */ +static void cred_init_security(void) +{ + struct cred *cred = (struct cred *) current->real_cred; + struct task_security_struct *tsec; + + tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); + if (!tsec) + panic("SELinux: Failed to initialize initial task.\n"); + + tsec->osid = tsec->sid = SECINITSID_KERNEL; + cred->security = tsec; +} + +/* + * get the security ID of a set of credentials + */ +static inline u32 cred_sid(const struct cred *cred) +{ + const struct task_security_struct *tsec; + + tsec = cred->security; + return tsec->sid; +} + +/* + * get the objective security ID of a task + */ +static inline u32 task_sid(const struct task_struct *task) +{ + u32 sid; + + rcu_read_lock(); + sid = cred_sid(__task_cred(task)); + rcu_read_unlock(); + return sid; +} + +/* + * get the subjective security ID of the current task + */ +static inline u32 current_sid(void) +{ + const struct task_security_struct *tsec = current_security(); + + return tsec->sid; +} + +/* Allocate and free functions for each kind of security blob. */ + +static int inode_alloc_security(struct inode *inode) +{ + struct inode_security_struct *isec; + u32 sid = current_sid(); + + isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); + if (!isec) + return -ENOMEM; + + mutex_init(&isec->lock); + INIT_LIST_HEAD(&isec->list); + isec->inode = inode; + isec->sid = SECINITSID_UNLABELED; + isec->sclass = SECCLASS_FILE; + isec->task_sid = sid; + inode->i_security = isec; + + return 0; +} + +static void inode_free_security(struct inode *inode) +{ + struct inode_security_struct *isec = inode->i_security; + struct superblock_security_struct *sbsec = inode->i_sb->s_security; + + spin_lock(&sbsec->isec_lock); + if (!list_empty(&isec->list)) + list_del_init(&isec->list); + spin_unlock(&sbsec->isec_lock); + + inode->i_security = NULL; + kmem_cache_free(sel_inode_cache, isec); +} + +static int file_alloc_security(struct file *file) +{ + struct file_security_struct *fsec; + u32 sid = current_sid(); + + fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); + if (!fsec) + return -ENOMEM; + + fsec->sid = sid; + fsec->fown_sid = sid; + file->f_security = fsec; + + return 0; +} + +static void file_free_security(struct file *file) +{ + struct file_security_struct *fsec = file->f_security; + file->f_security = NULL; + kfree(fsec); +} + +static int superblock_alloc_security(struct super_block *sb) +{ + struct superblock_security_struct *sbsec; + + sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); + if (!sbsec) + return -ENOMEM; + + mutex_init(&sbsec->lock); + INIT_LIST_HEAD(&sbsec->isec_head); + spin_lock_init(&sbsec->isec_lock); + sbsec->sb = sb; + sbsec->sid = SECINITSID_UNLABELED; + sbsec->def_sid = SECINITSID_FILE; + sbsec->mntpoint_sid = SECINITSID_UNLABELED; + sb->s_security = sbsec; + + return 0; +} + +static void superblock_free_security(struct super_block *sb) +{ + struct superblock_security_struct *sbsec = sb->s_security; + sb->s_security = NULL; + kfree(sbsec); +} + +/* The security server must be initialized before + any labeling or access decisions can be provided. */ +extern int ss_initialized; + +/* The file system's label must be initialized prior to use. */ + +static const char *labeling_behaviors[6] = { + "uses xattr", + "uses transition SIDs", + "uses task SIDs", + "uses genfs_contexts", + "not configured for labeling", + "uses mountpoint labeling", +}; + +static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); + +static inline int inode_doinit(struct inode *inode) +{ + return inode_doinit_with_dentry(inode, NULL); +} + +enum { + Opt_error = -1, + Opt_context = 1, + Opt_fscontext = 2, + Opt_defcontext = 3, + Opt_rootcontext = 4, + Opt_labelsupport = 5, +}; + +static const match_table_t tokens = { + {Opt_context, CONTEXT_STR "%s"}, + {Opt_fscontext, FSCONTEXT_STR "%s"}, + {Opt_defcontext, DEFCONTEXT_STR "%s"}, + {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, + {Opt_labelsupport, LABELSUPP_STR}, + {Opt_error, NULL}, +}; + +#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" + +static int may_context_mount_sb_relabel(u32 sid, + struct superblock_security_struct *sbsec, + const struct cred *cred) +{ + const struct task_security_struct *tsec = cred->security; + int rc; + + rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, + FILESYSTEM__RELABELFROM, NULL); + if (rc) + return rc; + + rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, + FILESYSTEM__RELABELTO, NULL); + return rc; +} + +static int may_context_mount_inode_relabel(u32 sid, + struct superblock_security_struct *sbsec, + const struct cred *cred) +{ + const struct task_security_struct *tsec = cred->security; + int rc; + rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, + FILESYSTEM__RELABELFROM, NULL); + if (rc) + return rc; + + rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, + FILESYSTEM__ASSOCIATE, NULL); + return rc; +} + +static int sb_finish_set_opts(struct super_block *sb) +{ + struct superblock_security_struct *sbsec = sb->s_security; + struct dentry *root = sb->s_root; + struct inode *root_inode = root->d_inode; + int rc = 0; + + if (sbsec->behavior == SECURITY_FS_USE_XATTR) { + /* Make sure that the xattr handler exists and that no + error other than -ENODATA is returned by getxattr on + the root directory. -ENODATA is ok, as this may be + the first boot of the SELinux kernel before we have + assigned xattr values to the filesystem. */ + if (!root_inode->i_op->getxattr) { + printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " + "xattr support\n", sb->s_id, sb->s_type->name); + rc = -EOPNOTSUPP; + goto out; + } + rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); + if (rc < 0 && rc != -ENODATA) { + if (rc == -EOPNOTSUPP) + printk(KERN_WARNING "SELinux: (dev %s, type " + "%s) has no security xattr handler\n", + sb->s_id, sb->s_type->name); + else + printk(KERN_WARNING "SELinux: (dev %s, type " + "%s) getxattr errno %d\n", sb->s_id, + sb->s_type->name, -rc); + goto out; + } + } + + sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); + + if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) + printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", + sb->s_id, sb->s_type->name); + else + printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", + sb->s_id, sb->s_type->name, + labeling_behaviors[sbsec->behavior-1]); + + if (sbsec->behavior == SECURITY_FS_USE_GENFS || + sbsec->behavior == SECURITY_FS_USE_MNTPOINT || + sbsec->behavior == SECURITY_FS_USE_NONE || + sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) + sbsec->flags &= ~SE_SBLABELSUPP; + + /* Special handling for sysfs. Is genfs but also has setxattr handler*/ + if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) + sbsec->flags |= SE_SBLABELSUPP; + + /* Initialize the root inode. */ + rc = inode_doinit_with_dentry(root_inode, root); + + /* Initialize any other inodes associated with the superblock, e.g. + inodes created prior to initial policy load or inodes created + during get_sb by a pseudo filesystem that directly + populates itself. */ + spin_lock(&sbsec->isec_lock); +next_inode: + if (!list_empty(&sbsec->isec_head)) { + struct inode_security_struct *isec = + list_entry(sbsec->isec_head.next, + struct inode_security_struct, list); + struct inode *inode = isec->inode; + spin_unlock(&sbsec->isec_lock); + inode = igrab(inode); + if (inode) { + if (!IS_PRIVATE(inode)) + inode_doinit(inode); + iput(inode); + } + spin_lock(&sbsec->isec_lock); + list_del_init(&isec->list); + goto next_inode; + } + spin_unlock(&sbsec->isec_lock); +out: + return rc; +} + +/* + * This function should allow an FS to ask what it's mount security + * options were so it can use those later for submounts, displaying + * mount options, or whatever. + */ +static int selinux_get_mnt_opts(const struct super_block *sb, + struct security_mnt_opts *opts) +{ + int rc = 0, i; + struct superblock_security_struct *sbsec = sb->s_security; + char *context = NULL; + u32 len; + char tmp; + + security_init_mnt_opts(opts); + + if (!(sbsec->flags & SE_SBINITIALIZED)) + return -EINVAL; + + if (!ss_initialized) + return -EINVAL; + + tmp = sbsec->flags & SE_MNTMASK; + /* count the number of mount options for this sb */ + for (i = 0; i < 8; i++) { + if (tmp & 0x01) + opts->num_mnt_opts++; + tmp >>= 1; + } + /* Check if the Label support flag is set */ + if (sbsec->flags & SE_SBLABELSUPP) + opts->num_mnt_opts++; + + opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); + if (!opts->mnt_opts) { + rc = -ENOMEM; + goto out_free; + } + + opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); + if (!opts->mnt_opts_flags) { + rc = -ENOMEM; + goto out_free; + } + + i = 0; + if (sbsec->flags & FSCONTEXT_MNT) { + rc = security_sid_to_context(sbsec->sid, &context, &len); + if (rc) + goto out_free; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; + } + if (sbsec->flags & CONTEXT_MNT) { + rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); + if (rc) + goto out_free; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = CONTEXT_MNT; + } + if (sbsec->flags & DEFCONTEXT_MNT) { + rc = security_sid_to_context(sbsec->def_sid, &context, &len); + if (rc) + goto out_free; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; + } + if (sbsec->flags & ROOTCONTEXT_MNT) { + struct inode *root = sbsec->sb->s_root->d_inode; + struct inode_security_struct *isec = root->i_security; + + rc = security_sid_to_context(isec->sid, &context, &len); + if (rc) + goto out_free; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; + } + if (sbsec->flags & SE_SBLABELSUPP) { + opts->mnt_opts[i] = NULL; + opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; + } + + BUG_ON(i != opts->num_mnt_opts); + + return 0; + +out_free: + security_free_mnt_opts(opts); + return rc; +} + +static int bad_option(struct superblock_security_struct *sbsec, char flag, + u32 old_sid, u32 new_sid) +{ + char mnt_flags = sbsec->flags & SE_MNTMASK; + + /* check if the old mount command had the same options */ + if (sbsec->flags & SE_SBINITIALIZED) + if (!(sbsec->flags & flag) || + (old_sid != new_sid)) + return 1; + + /* check if we were passed the same options twice, + * aka someone passed context=a,context=b + */ + if (!(sbsec->flags & SE_SBINITIALIZED)) + if (mnt_flags & flag) + return 1; + return 0; +} + +/* + * Allow filesystems with binary mount data to explicitly set mount point + * labeling information. + */ +static int selinux_set_mnt_opts(struct super_block *sb, + struct security_mnt_opts *opts) +{ + const struct cred *cred = current_cred(); + int rc = 0, i; + struct superblock_security_struct *sbsec = sb->s_security; + const char *name = sb->s_type->name; + struct inode *inode = sbsec->sb->s_root->d_inode; + struct inode_security_struct *root_isec = inode->i_security; + u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; + u32 defcontext_sid = 0; + char **mount_options = opts->mnt_opts; + int *flags = opts->mnt_opts_flags; + int num_opts = opts->num_mnt_opts; + + mutex_lock(&sbsec->lock); + + if (!ss_initialized) { + if (!num_opts) { + /* Defer initialization until selinux_complete_init, + after the initial policy is loaded and the security + server is ready to handle calls. */ + goto out; + } + rc = -EINVAL; + printk(KERN_WARNING "SELinux: Unable to set superblock options " + "before the security server is initialized\n"); + goto out; + } + + /* + * Binary mount data FS will come through this function twice. Once + * from an explicit call and once from the generic calls from the vfs. + * Since the generic VFS calls will not contain any security mount data + * we need to skip the double mount verification. + * + * This does open a hole in which we will not notice if the first + * mount using this sb set explict options and a second mount using + * this sb does not set any security options. (The first options + * will be used for both mounts) + */ + if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) + && (num_opts == 0)) + goto out; + + /* + * parse the mount options, check if they are valid sids. + * also check if someone is trying to mount the same sb more + * than once with different security options. + */ + for (i = 0; i < num_opts; i++) { + u32 sid; + + if (flags[i] == SE_SBLABELSUPP) + continue; + rc = security_context_to_sid(mount_options[i], + strlen(mount_options[i]), &sid); + if (rc) { + printk(KERN_WARNING "SELinux: security_context_to_sid" + "(%s) failed for (dev %s, type %s) errno=%d\n", + mount_options[i], sb->s_id, name, rc); + goto out; + } + switch (flags[i]) { + case FSCONTEXT_MNT: + fscontext_sid = sid; + + if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, + fscontext_sid)) + goto out_double_mount; + + sbsec->flags |= FSCONTEXT_MNT; + break; + case CONTEXT_MNT: + context_sid = sid; + + if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, + context_sid)) + goto out_double_mount; + + sbsec->flags |= CONTEXT_MNT; + break; + case ROOTCONTEXT_MNT: + rootcontext_sid = sid; + + if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, + rootcontext_sid)) + goto out_double_mount; + + sbsec->flags |= ROOTCONTEXT_MNT; + + break; + case DEFCONTEXT_MNT: + defcontext_sid = sid; + + if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, + defcontext_sid)) + goto out_double_mount; + + sbsec->flags |= DEFCONTEXT_MNT; + + break; + default: + rc = -EINVAL; + goto out; + } + } + + if (sbsec->flags & SE_SBINITIALIZED) { + /* previously mounted with options, but not on this attempt? */ + if ((sbsec->flags & SE_MNTMASK) && !num_opts) + goto out_double_mount; + rc = 0; + goto out; + } + + if (strcmp(sb->s_type->name, "proc") == 0) + sbsec->flags |= SE_SBPROC; + + /* Determine the labeling behavior to use for this filesystem type. */ + rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); + if (rc) { + printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", + __func__, sb->s_type->name, rc); + goto out; + } + + /* sets the context of the superblock for the fs being mounted. */ + if (fscontext_sid) { + rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); + if (rc) + goto out; + + sbsec->sid = fscontext_sid; + } + + /* + * Switch to using mount point labeling behavior. + * sets the label used on all file below the mountpoint, and will set + * the superblock context if not already set. + */ + if (context_sid) { + if (!fscontext_sid) { + rc = may_context_mount_sb_relabel(context_sid, sbsec, + cred); + if (rc) + goto out; + sbsec->sid = context_sid; + } else { + rc = may_context_mount_inode_relabel(context_sid, sbsec, + cred); + if (rc) + goto out; + } + if (!rootcontext_sid) + rootcontext_sid = context_sid; + + sbsec->mntpoint_sid = context_sid; + sbsec->behavior = SECURITY_FS_USE_MNTPOINT; + } + + if (rootcontext_sid) { + rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, + cred); + if (rc) + goto out; + + root_isec->sid = rootcontext_sid; + root_isec->initialized = 1; + } + + if (defcontext_sid) { + if (sbsec->behavior != SECURITY_FS_USE_XATTR) { + rc = -EINVAL; + printk(KERN_WARNING "SELinux: defcontext option is " + "invalid for this filesystem type\n"); + goto out; + } + + if (defcontext_sid != sbsec->def_sid) { + rc = may_context_mount_inode_relabel(defcontext_sid, + sbsec, cred); + if (rc) + goto out; + } + + sbsec->def_sid = defcontext_sid; + } + + rc = sb_finish_set_opts(sb); +out: + mutex_unlock(&sbsec->lock); + return rc; +out_double_mount: + rc = -EINVAL; + printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " + "security settings for (dev %s, type %s)\n", sb->s_id, name); + goto out; +} + +static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, + struct super_block *newsb) +{ + const struct superblock_security_struct *oldsbsec = oldsb->s_security; + struct superblock_security_struct *newsbsec = newsb->s_security; + + int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); + int set_context = (oldsbsec->flags & CONTEXT_MNT); + int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); + + /* + * if the parent was able to be mounted it clearly had no special lsm + * mount options. thus we can safely deal with this superblock later + */ + if (!ss_initialized) + return; + + /* how can we clone if the old one wasn't set up?? */ + BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); + + /* if fs is reusing a sb, just let its options stand... */ + if (newsbsec->flags & SE_SBINITIALIZED) + return; + + mutex_lock(&newsbsec->lock); + + newsbsec->flags = oldsbsec->flags; + + newsbsec->sid = oldsbsec->sid; + newsbsec->def_sid = oldsbsec->def_sid; + newsbsec->behavior = oldsbsec->behavior; + + if (set_context) { + u32 sid = oldsbsec->mntpoint_sid; + + if (!set_fscontext) + newsbsec->sid = sid; + if (!set_rootcontext) { + struct inode *newinode = newsb->s_root->d_inode; + struct inode_security_struct *newisec = newinode->i_security; + newisec->sid = sid; + } + newsbsec->mntpoint_sid = sid; + } + if (set_rootcontext) { + const struct inode *oldinode = oldsb->s_root->d_inode; + const struct inode_security_struct *oldisec = oldinode->i_security; + struct inode *newinode = newsb->s_root->d_inode; + struct inode_security_struct *newisec = newinode->i_security; + + newisec->sid = oldisec->sid; + } + + sb_finish_set_opts(newsb); + mutex_unlock(&newsbsec->lock); +} + +static int selinux_parse_opts_str(char *options, + struct security_mnt_opts *opts) +{ + char *p; + char *context = NULL, *defcontext = NULL; + char *fscontext = NULL, *rootcontext = NULL; + int rc, num_mnt_opts = 0; + + opts->num_mnt_opts = 0; + + /* Standard string-based options. */ + while ((p = strsep(&options, "|")) != NULL) { + int token; + substring_t args[MAX_OPT_ARGS]; + + if (!*p) + continue; + + token = match_token(p, tokens, args); + + switch (token) { + case Opt_context: + if (context || defcontext) { + rc = -EINVAL; + printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); + goto out_err; + } + context = match_strdup(&args[0]); + if (!context) { + rc = -ENOMEM; + goto out_err; + } + break; + + case Opt_fscontext: + if (fscontext) { + rc = -EINVAL; + printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); + goto out_err; + } + fscontext = match_strdup(&args[0]); + if (!fscontext) { + rc = -ENOMEM; + goto out_err; + } + break; + + case Opt_rootcontext: + if (rootcontext) { + rc = -EINVAL; + printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); + goto out_err; + } + rootcontext = match_strdup(&args[0]); + if (!rootcontext) { + rc = -ENOMEM; + goto out_err; + } + break; + + case Opt_defcontext: + if (context || defcontext) { + rc = -EINVAL; + printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); + goto out_err; + } + defcontext = match_strdup(&args[0]); + if (!defcontext) { + rc = -ENOMEM; + goto out_err; + } + break; + case Opt_labelsupport: + break; + default: + rc = -EINVAL; + printk(KERN_WARNING "SELinux: unknown mount option\n"); + goto out_err; + + } + } + + rc = -ENOMEM; + opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); + if (!opts->mnt_opts) + goto out_err; + + opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); + if (!opts->mnt_opts_flags) { + kfree(opts->mnt_opts); + goto out_err; + } + + if (fscontext) { + opts->mnt_opts[num_mnt_opts] = fscontext; + opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; + } + if (context) { + opts->mnt_opts[num_mnt_opts] = context; + opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; + } + if (rootcontext) { + opts->mnt_opts[num_mnt_opts] = rootcontext; + opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; + } + if (defcontext) { + opts->mnt_opts[num_mnt_opts] = defcontext; + opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; + } + + opts->num_mnt_opts = num_mnt_opts; + return 0; + +out_err: + kfree(context); + kfree(defcontext); + kfree(fscontext); + kfree(rootcontext); + return rc; +} +/* + * string mount options parsing and call set the sbsec + */ +static int superblock_doinit(struct super_block *sb, void *data) +{ + int rc = 0; + char *options = data; + struct security_mnt_opts opts; + + security_init_mnt_opts(&opts); + + if (!data) + goto out; + + BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); + + rc = selinux_parse_opts_str(options, &opts); + if (rc) + goto out_err; + +out: + rc = selinux_set_mnt_opts(sb, &opts); + +out_err: + security_free_mnt_opts(&opts); + return rc; +} + +static void selinux_write_opts(struct seq_file *m, + struct security_mnt_opts *opts) +{ + int i; + char *prefix; + + for (i = 0; i < opts->num_mnt_opts; i++) { + char *has_comma; + + if (opts->mnt_opts[i]) + has_comma = strchr(opts->mnt_opts[i], ','); + else + has_comma = NULL; + + switch (opts->mnt_opts_flags[i]) { + case CONTEXT_MNT: + prefix = CONTEXT_STR; + break; + case FSCONTEXT_MNT: + prefix = FSCONTEXT_STR; + break; + case ROOTCONTEXT_MNT: + prefix = ROOTCONTEXT_STR; + break; + case DEFCONTEXT_MNT: + prefix = DEFCONTEXT_STR; + break; + case SE_SBLABELSUPP: + seq_putc(m, ','); + seq_puts(m, LABELSUPP_STR); + continue; + default: + BUG(); + return; + }; + /* we need a comma before each option */ + seq_putc(m, ','); + seq_puts(m, prefix); + if (has_comma) + seq_putc(m, '\"'); + seq_puts(m, opts->mnt_opts[i]); + if (has_comma) + seq_putc(m, '\"'); + } +} + +static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) +{ + struct security_mnt_opts opts; + int rc; + + rc = selinux_get_mnt_opts(sb, &opts); + if (rc) { + /* before policy load we may get EINVAL, don't show anything */ + if (rc == -EINVAL) + rc = 0; + return rc; + } + + selinux_write_opts(m, &opts); + + security_free_mnt_opts(&opts); + + return rc; +} + +static inline u16 inode_mode_to_security_class(umode_t mode) +{ + switch (mode & S_IFMT) { + case S_IFSOCK: + return SECCLASS_SOCK_FILE; + case S_IFLNK: + return SECCLASS_LNK_FILE; + case S_IFREG: + return SECCLASS_FILE; + case S_IFBLK: + return SECCLASS_BLK_FILE; + case S_IFDIR: + return SECCLASS_DIR; + case S_IFCHR: + return SECCLASS_CHR_FILE; + case S_IFIFO: + return SECCLASS_FIFO_FILE; + + } + + return SECCLASS_FILE; +} + +static inline int default_protocol_stream(int protocol) +{ + return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); +} + +static inline int default_protocol_dgram(int protocol) +{ + return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); +} + +static inline u16 socket_type_to_security_class(int family, int type, int protocol) +{ + switch (family) { + case PF_UNIX: + switch (type) { + case SOCK_STREAM: + case SOCK_SEQPACKET: + return SECCLASS_UNIX_STREAM_SOCKET; + case SOCK_DGRAM: + return SECCLASS_UNIX_DGRAM_SOCKET; + } + break; + case PF_INET: + case PF_INET6: + switch (type) { + case SOCK_STREAM: + if (default_protocol_stream(protocol)) + return SECCLASS_TCP_SOCKET; + else + return SECCLASS_RAWIP_SOCKET; + case SOCK_DGRAM: + if (default_protocol_dgram(protocol)) + return SECCLASS_UDP_SOCKET; + else + return SECCLASS_RAWIP_SOCKET; + case SOCK_DCCP: + return SECCLASS_DCCP_SOCKET; + default: + return SECCLASS_RAWIP_SOCKET; + } + break; + case PF_NETLINK: + switch (protocol) { + case NETLINK_ROUTE: + return SECCLASS_NETLINK_ROUTE_SOCKET; + case NETLINK_FIREWALL: + return SECCLASS_NETLINK_FIREWALL_SOCKET; + case NETLINK_INET_DIAG: + return SECCLASS_NETLINK_TCPDIAG_SOCKET; + case NETLINK_NFLOG: + return SECCLASS_NETLINK_NFLOG_SOCKET; + case NETLINK_XFRM: + return SECCLASS_NETLINK_XFRM_SOCKET; + case NETLINK_SELINUX: + return SECCLASS_NETLINK_SELINUX_SOCKET; + case NETLINK_AUDIT: + return SECCLASS_NETLINK_AUDIT_SOCKET; + case NETLINK_IP6_FW: + return SECCLASS_NETLINK_IP6FW_SOCKET; + case NETLINK_DNRTMSG: + return SECCLASS_NETLINK_DNRT_SOCKET; + case NETLINK_KOBJECT_UEVENT: + return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; + default: + return SECCLASS_NETLINK_SOCKET; + } + case PF_PACKET: + return SECCLASS_PACKET_SOCKET; + case PF_KEY: + return SECCLASS_KEY_SOCKET; + case PF_APPLETALK: + return SECCLASS_APPLETALK_SOCKET; + } + + return SECCLASS_SOCKET; +} + +#ifdef CONFIG_PROC_FS +static int selinux_proc_get_sid(struct dentry *dentry, + u16 tclass, + u32 *sid) +{ + int rc; + char *buffer, *path; + + buffer = (char *)__get_free_page(GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + path = dentry_path_raw(dentry, buffer, PAGE_SIZE); + if (IS_ERR(path)) + rc = PTR_ERR(path); + else { + /* each process gets a /proc/PID/ entry. Strip off the + * PID part to get a valid selinux labeling. + * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ + while (path[1] >= '0' && path[1] <= '9') { + path[1] = '/'; + path++; + } + rc = security_genfs_sid("proc", path, tclass, sid); + } + free_page((unsigned long)buffer); + return rc; +} +#else +static int selinux_proc_get_sid(struct dentry *dentry, + u16 tclass, + u32 *sid) +{ + return -EINVAL; +} +#endif + +/* The inode's security attributes must be initialized before first use. */ +static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) +{ + struct superblock_security_struct *sbsec = NULL; + struct inode_security_struct *isec = inode->i_security; + u32 sid; + struct dentry *dentry; +#define INITCONTEXTLEN 255 + char *context = NULL; + unsigned len = 0; + int rc = 0; + + if (isec->initialized) + goto out; + + mutex_lock(&isec->lock); + if (isec->initialized) + goto out_unlock; + + sbsec = inode->i_sb->s_security; + if (!(sbsec->flags & SE_SBINITIALIZED)) { + /* Defer initialization until selinux_complete_init, + after the initial policy is loaded and the security + server is ready to handle calls. */ + spin_lock(&sbsec->isec_lock); + if (list_empty(&isec->list)) + list_add(&isec->list, &sbsec->isec_head); + spin_unlock(&sbsec->isec_lock); + goto out_unlock; + } + + switch (sbsec->behavior) { + case SECURITY_FS_USE_XATTR: + if (!inode->i_op->getxattr) { + isec->sid = sbsec->def_sid; + break; + } + + /* Need a dentry, since the xattr API requires one. + Life would be simpler if we could just pass the inode. */ + if (opt_dentry) { + /* Called from d_instantiate or d_splice_alias. */ + dentry = dget(opt_dentry); + } else { + /* Called from selinux_complete_init, try to find a dentry. */ + dentry = d_find_alias(inode); + } + if (!dentry) { + /* + * this is can be hit on boot when a file is accessed + * before the policy is loaded. When we load policy we + * may find inodes that have no dentry on the + * sbsec->isec_head list. No reason to complain as these + * will get fixed up the next time we go through + * inode_doinit with a dentry, before these inodes could + * be used again by userspace. + */ + goto out_unlock; + } + + len = INITCONTEXTLEN; + context = kmalloc(len+1, GFP_NOFS); + if (!context) { + rc = -ENOMEM; + dput(dentry); + goto out_unlock; + } + context[len] = '\0'; + rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, + context, len); + if (rc == -ERANGE) { + kfree(context); + + /* Need a larger buffer. Query for the right size. */ + rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, + NULL, 0); + if (rc < 0) { + dput(dentry); + goto out_unlock; + } + len = rc; + context = kmalloc(len+1, GFP_NOFS); + if (!context) { + rc = -ENOMEM; + dput(dentry); + goto out_unlock; + } + context[len] = '\0'; + rc = inode->i_op->getxattr(dentry, + XATTR_NAME_SELINUX, + context, len); + } + dput(dentry); + if (rc < 0) { + if (rc != -ENODATA) { + printk(KERN_WARNING "SELinux: %s: getxattr returned " + "%d for dev=%s ino=%ld\n", __func__, + -rc, inode->i_sb->s_id, inode->i_ino); + kfree(context); + goto out_unlock; + } + /* Map ENODATA to the default file SID */ + sid = sbsec->def_sid; + rc = 0; + } else { + rc = security_context_to_sid_default(context, rc, &sid, + sbsec->def_sid, + GFP_NOFS); + if (rc) { + char *dev = inode->i_sb->s_id; + unsigned long ino = inode->i_ino; + + if (rc == -EINVAL) { + if (printk_ratelimit()) + printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " + "context=%s. This indicates you may need to relabel the inode or the " + "filesystem in question.\n", ino, dev, context); + } else { + printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " + "returned %d for dev=%s ino=%ld\n", + __func__, context, -rc, dev, ino); + } + kfree(context); + /* Leave with the unlabeled SID */ + rc = 0; + break; + } + } + kfree(context); + isec->sid = sid; + break; + case SECURITY_FS_USE_TASK: + isec->sid = isec->task_sid; + break; + case SECURITY_FS_USE_TRANS: + /* Default to the fs SID. */ + isec->sid = sbsec->sid; + + /* Try to obtain a transition SID. */ + isec->sclass = inode_mode_to_security_class(inode->i_mode); + rc = security_transition_sid(isec->task_sid, sbsec->sid, + isec->sclass, NULL, &sid); + if (rc) + goto out_unlock; + isec->sid = sid; + break; + case SECURITY_FS_USE_MNTPOINT: + isec->sid = sbsec->mntpoint_sid; + break; + default: + /* Default to the fs superblock SID. */ + isec->sid = sbsec->sid; + + if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { + if (opt_dentry) { + isec->sclass = inode_mode_to_security_class(inode->i_mode); + rc = selinux_proc_get_sid(opt_dentry, + isec->sclass, + &sid); + if (rc) + goto out_unlock; + isec->sid = sid; + } + } + break; + } + + isec->initialized = 1; + +out_unlock: + mutex_unlock(&isec->lock); +out: + if (isec->sclass == SECCLASS_FILE) + isec->sclass = inode_mode_to_security_class(inode->i_mode); + return rc; +} + +/* Convert a Linux signal to an access vector. */ +static inline u32 signal_to_av(int sig) +{ + u32 perm = 0; + + switch (sig) { + case SIGCHLD: + /* Commonly granted from child to parent. */ + perm = PROCESS__SIGCHLD; + break; + case SIGKILL: + /* Cannot be caught or ignored */ + perm = PROCESS__SIGKILL; + break; + case SIGSTOP: + /* Cannot be caught or ignored */ + perm = PROCESS__SIGSTOP; + break; + default: + /* All other signals. */ + perm = PROCESS__SIGNAL; + break; + } + + return perm; +} + +/* + * Check permission between a pair of credentials + * fork check, ptrace check, etc. + */ +static int cred_has_perm(const struct cred *actor, + const struct cred *target, + u32 perms) +{ + u32 asid = cred_sid(actor), tsid = cred_sid(target); + + return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); +} + +/* + * Check permission between a pair of tasks, e.g. signal checks, + * fork check, ptrace check, etc. + * tsk1 is the actor and tsk2 is the target + * - this uses the default subjective creds of tsk1 + */ +static int task_has_perm(const struct task_struct *tsk1, + const struct task_struct *tsk2, + u32 perms) +{ + const struct task_security_struct *__tsec1, *__tsec2; + u32 sid1, sid2; + + rcu_read_lock(); + __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; + __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; + rcu_read_unlock(); + return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); +} + +/* + * Check permission between current and another task, e.g. signal checks, + * fork check, ptrace check, etc. + * current is the actor and tsk2 is the target + * - this uses current's subjective creds + */ +static int current_has_perm(const struct task_struct *tsk, + u32 perms) +{ + u32 sid, tsid; + + sid = current_sid(); + tsid = task_sid(tsk); + return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); +} + +#if CAP_LAST_CAP > 63 +#error Fix SELinux to handle capabilities > 63. +#endif + +/* Check whether a task is allowed to use a capability. */ +static int task_has_capability(struct task_struct *tsk, + const struct cred *cred, + int cap, int audit) +{ + struct common_audit_data ad; + struct av_decision avd; + u16 sclass; + u32 sid = cred_sid(cred); + u32 av = CAP_TO_MASK(cap); + int rc; + + COMMON_AUDIT_DATA_INIT(&ad, CAP); + ad.tsk = tsk; + ad.u.cap = cap; + + switch (CAP_TO_INDEX(cap)) { + case 0: + sclass = SECCLASS_CAPABILITY; + break; + case 1: + sclass = SECCLASS_CAPABILITY2; + break; + default: + printk(KERN_ERR + "SELinux: out of range capability %d\n", cap); + BUG(); + return -EINVAL; + } + + rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); + if (audit == SECURITY_CAP_AUDIT) { + int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); + if (rc2) + return rc2; + } + return rc; +} + +/* Check whether a task is allowed to use a system operation. */ +static int task_has_system(struct task_struct *tsk, + u32 perms) +{ + u32 sid = task_sid(tsk); + + return avc_has_perm(sid, SECINITSID_KERNEL, + SECCLASS_SYSTEM, perms, NULL); +} + +/* Check whether a task has a particular permission to an inode. + The 'adp' parameter is optional and allows other audit + data to be passed (e.g. the dentry). */ +static int inode_has_perm(const struct cred *cred, + struct inode *inode, + u32 perms, + struct common_audit_data *adp, + unsigned flags) +{ + struct inode_security_struct *isec; + u32 sid; + + validate_creds(cred); + + if (unlikely(IS_PRIVATE(inode))) + return 0; + + sid = cred_sid(cred); + isec = inode->i_security; + + return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags); +} + +static int inode_has_perm_noadp(const struct cred *cred, + struct inode *inode, + u32 perms, + unsigned flags) +{ + struct common_audit_data ad; + + COMMON_AUDIT_DATA_INIT(&ad, INODE); + ad.u.inode = inode; + return inode_has_perm(cred, inode, perms, &ad, flags); +} + +/* Same as inode_has_perm, but pass explicit audit data containing + the dentry to help the auditing code to more easily generate the + pathname if needed. */ +static inline int dentry_has_perm(const struct cred *cred, + struct dentry *dentry, + u32 av) +{ + struct inode *inode = dentry->d_inode; + struct common_audit_data ad; + + COMMON_AUDIT_DATA_INIT(&ad, DENTRY); + ad.u.dentry = dentry; + return inode_has_perm(cred, inode, av, &ad, 0); +} + +/* Same as inode_has_perm, but pass explicit audit data containing + the path to help the auditing code to more easily generate the + pathname if needed. */ +static inline int path_has_perm(const struct cred *cred, + struct path *path, + u32 av) +{ + struct inode *inode = path->dentry->d_inode; + struct common_audit_data ad; + + COMMON_AUDIT_DATA_INIT(&ad, PATH); + ad.u.path = *path; + return inode_has_perm(cred, inode, av, &ad, 0); +} + +/* Check whether a task can use an open file descriptor to + access an inode in a given way. Check access to the + descriptor itself, and then use dentry_has_perm to + check a particular permission to the file. + Access to the descriptor is implicitly granted if it + has the same SID as the process. If av is zero, then + access to the file is not checked, e.g. for cases + where only the descriptor is affected like seek. */ +static int file_has_perm(const struct cred *cred, + struct file *file, + u32 av) +{ + struct file_security_struct *fsec = file->f_security; + struct inode *inode = file->f_path.dentry->d_inode; + struct common_audit_data ad; + u32 sid = cred_sid(cred); + int rc; + + COMMON_AUDIT_DATA_INIT(&ad, PATH); + ad.u.path = file->f_path; + + if (sid != fsec->sid) { + rc = avc_has_perm(sid, fsec->sid, + SECCLASS_FD, + FD__USE, + &ad); + if (rc) + goto out; + } + + /* av is zero if only checking access to the descriptor. */ + rc = 0; + if (av) + rc = inode_has_perm(cred, inode, av, &ad, 0); + +out: + return rc; +} + +/* Check whether a task can create a file. */ +static int may_create(struct inode *dir, + struct dentry *dentry, + u16 tclass) +{ + const struct task_security_struct *tsec = current_security(); + struct inode_security_struct *dsec; + struct superblock_security_struct *sbsec; + u32 sid, newsid; + struct common_audit_data ad; + int rc; + + dsec = dir->i_security; + sbsec = dir->i_sb->s_security; + + sid = tsec->sid; + newsid = tsec->create_sid; + + COMMON_AUDIT_DATA_INIT(&ad, DENTRY); + ad.u.dentry = dentry; + + rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, + DIR__ADD_NAME | DIR__SEARCH, + &ad); + if (rc) + return rc; + + if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { + rc = security_transition_sid(sid, dsec->sid, tclass, + &dentry->d_name, &newsid); + if (rc) + return rc; + } + + rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); + if (rc) + return rc; + + return avc_has_perm(newsid, sbsec->sid, + SECCLASS_FILESYSTEM, + FILESYSTEM__ASSOCIATE, &ad); +} + +/* Check whether a task can create a key. */ +static int may_create_key(u32 ksid, + struct task_struct *ctx) +{ + u32 sid = task_sid(ctx); + + return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); +} + +#define MAY_LINK 0 +#define MAY_UNLINK 1 +#define MAY_RMDIR 2 + +/* Check whether a task can link, unlink, or rmdir a file/directory. */ +static int may_link(struct inode *dir, + struct dentry *dentry, + int kind) + +{ + struct inode_security_struct *dsec, *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + u32 av; + int rc; + + dsec = dir->i_security; + isec = dentry->d_inode->i_security; + + COMMON_AUDIT_DATA_INIT(&ad, DENTRY); + ad.u.dentry = dentry; + + av = DIR__SEARCH; + av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); + rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); + if (rc) + return rc; + + switch (kind) { + case MAY_LINK: + av = FILE__LINK; + break; + case MAY_UNLINK: + av = FILE__UNLINK; + break; + case MAY_RMDIR: + av = DIR__RMDIR; + break; + default: + printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", + __func__, kind); + return 0; + } + + rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); + return rc; +} + +static inline int may_rename(struct inode *old_dir, + struct dentry *old_dentry, + struct inode *new_dir, + struct dentry *new_dentry) +{ + struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; + struct common_audit_data ad; + u32 sid = current_sid(); + u32 av; + int old_is_dir, new_is_dir; + int rc; + + old_dsec = old_dir->i_security; + old_isec = old_dentry->d_inode->i_security; + old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); + new_dsec = new_dir->i_security; + + COMMON_AUDIT_DATA_INIT(&ad, DENTRY); + + ad.u.dentry = old_dentry; + rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, + DIR__REMOVE_NAME | DIR__SEARCH, &ad); + if (rc) + return rc; + rc = avc_has_perm(sid, old_isec->sid, + old_isec->sclass, FILE__RENAME, &ad); + if (rc) + return rc; + if (old_is_dir && new_dir != old_dir) { + rc = avc_has_perm(sid, old_isec->sid, + old_isec->sclass, DIR__REPARENT, &ad); + if (rc) + return rc; + } + + ad.u.dentry = new_dentry; + av = DIR__ADD_NAME | DIR__SEARCH; + if (new_dentry->d_inode) + av |= DIR__REMOVE_NAME; + rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); + if (rc) + return rc; + if (new_dentry->d_inode) { + new_isec = new_dentry->d_inode->i_security; + new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); + rc = avc_has_perm(sid, new_isec->sid, + new_isec->sclass, + (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); + if (rc) + return rc; + } + + return 0; +} + +/* Check whether a task can perform a filesystem operation. */ +static int superblock_has_perm(const struct cred *cred, + struct super_block *sb, + u32 perms, + struct common_audit_data *ad) +{ + struct superblock_security_struct *sbsec; + u32 sid = cred_sid(cred); + + sbsec = sb->s_security; + return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); +} + +/* Convert a Linux mode and permission mask to an access vector. */ +static inline u32 file_mask_to_av(int mode, int mask) +{ + u32 av = 0; + + if ((mode & S_IFMT) != S_IFDIR) { + if (mask & MAY_EXEC) + av |= FILE__EXECUTE; + if (mask & MAY_READ) + av |= FILE__READ; + + if (mask & MAY_APPEND) + av |= FILE__APPEND; + else if (mask & MAY_WRITE) + av |= FILE__WRITE; + + } else { + if (mask & MAY_EXEC) + av |= DIR__SEARCH; + if (mask & MAY_WRITE) + av |= DIR__WRITE; + if (mask & MAY_READ) + av |= DIR__READ; + } + + return av; +} + +/* Convert a Linux file to an access vector. */ +static inline u32 file_to_av(struct file *file) +{ + u32 av = 0; + + if (file->f_mode & FMODE_READ) + av |= FILE__READ; + if (file->f_mode & FMODE_WRITE) { + if (file->f_flags & O_APPEND) + av |= FILE__APPEND; + else + av |= FILE__WRITE; + } + if (!av) { + /* + * Special file opened with flags 3 for ioctl-only use. + */ + av = FILE__IOCTL; + } + + return av; +} + +/* + * Convert a file to an access vector and include the correct open + * open permission. + */ +static inline u32 open_file_to_av(struct file *file) +{ + u32 av = file_to_av(file); + + if (selinux_policycap_openperm) + av |= FILE__OPEN; + + return av; +} + +/* Hook functions begin here. */ + +static int selinux_ptrace_access_check(struct task_struct *child, + unsigned int mode) +{ + int rc; + + rc = cap_ptrace_access_check(child, mode); + if (rc) + return rc; + + if (mode == PTRACE_MODE_READ) { + u32 sid = current_sid(); + u32 csid = task_sid(child); + return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); + } + + return current_has_perm(child, PROCESS__PTRACE); +} + +static int selinux_ptrace_traceme(struct task_struct *parent) +{ + int rc; + + rc = cap_ptrace_traceme(parent); + if (rc) + return rc; + + return task_has_perm(parent, current, PROCESS__PTRACE); +} + +static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, + kernel_cap_t *inheritable, kernel_cap_t *permitted) +{ + int error; + + error = current_has_perm(target, PROCESS__GETCAP); + if (error) + return error; + + return cap_capget(target, effective, inheritable, permitted); +} + +static int selinux_capset(struct cred *new, const struct cred *old, + const kernel_cap_t *effective, + const kernel_cap_t *inheritable, + const kernel_cap_t *permitted) +{ + int error; + + error = cap_capset(new, old, + effective, inheritable, permitted); + if (error) + return error; + + return cred_has_perm(old, new, PROCESS__SETCAP); +} + +/* + * (This comment used to live with the selinux_task_setuid hook, + * which was removed). + * + * Since setuid only affects the current process, and since the SELinux + * controls are not based on the Linux identity attributes, SELinux does not + * need to control this operation. However, SELinux does control the use of + * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. + */ + +static int selinux_capable(struct task_struct *tsk, const struct cred *cred, + struct user_namespace *ns, int cap, int audit) +{ + int rc; + + rc = cap_capable(tsk, cred, ns, cap, audit); + if (rc) + return rc; + + return task_has_capability(tsk, cred, cap, audit); +} + +static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) +{ + const struct cred *cred = current_cred(); + int rc = 0; + + if (!sb) + return 0; + + switch (cmds) { + case Q_SYNC: + case Q_QUOTAON: + case Q_QUOTAOFF: + case Q_SETINFO: + case Q_SETQUOTA: + rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); + break; + case Q_GETFMT: + case Q_GETINFO: + case Q_GETQUOTA: + rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); + break; + default: + rc = 0; /* let the kernel handle invalid cmds */ + break; + } + return rc; +} + +static int selinux_quota_on(struct dentry *dentry) +{ + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, dentry, FILE__QUOTAON); +} + +static int selinux_syslog(int type) +{ + int rc; + + switch (type) { + case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ + case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ + rc = task_has_system(current, SYSTEM__SYSLOG_READ); + break; + case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ + case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ + /* Set level of messages printed to console */ + case SYSLOG_ACTION_CONSOLE_LEVEL: + rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); + break; + case SYSLOG_ACTION_CLOSE: /* Close log */ + case SYSLOG_ACTION_OPEN: /* Open log */ + case SYSLOG_ACTION_READ: /* Read from log */ + case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ + case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ + default: + rc = task_has_system(current, SYSTEM__SYSLOG_MOD); + break; + } + return rc; +} + +/* + * Check that a process has enough memory to allocate a new virtual + * mapping. 0 means there is enough memory for the allocation to + * succeed and -ENOMEM implies there is not. + * + * Do not audit the selinux permission check, as this is applied to all + * processes that allocate mappings. + */ +static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) +{ + int rc, cap_sys_admin = 0; + + rc = selinux_capable(current, current_cred(), + &init_user_ns, CAP_SYS_ADMIN, + SECURITY_CAP_NOAUDIT); + if (rc == 0) + cap_sys_admin = 1; + + return __vm_enough_memory(mm, pages, cap_sys_admin); +} + +/* binprm security operations */ + +static int selinux_bprm_set_creds(struct linux_binprm *bprm) +{ + const struct task_security_struct *old_tsec; + struct task_security_struct *new_tsec; + struct inode_security_struct *isec; + struct common_audit_data ad; + struct inode *inode = bprm->file->f_path.dentry->d_inode; + int rc; + + rc = cap_bprm_set_creds(bprm); + if (rc) + return rc; + + /* SELinux context only depends on initial program or script and not + * the script interpreter */ + if (bprm->cred_prepared) + return 0; + + old_tsec = current_security(); + new_tsec = bprm->cred->security; + isec = inode->i_security; + + /* Default to the current task SID. */ + new_tsec->sid = old_tsec->sid; + new_tsec->osid = old_tsec->sid; + + /* Reset fs, key, and sock SIDs on execve. */ + new_tsec->create_sid = 0; + new_tsec->keycreate_sid = 0; + new_tsec->sockcreate_sid = 0; + + if (old_tsec->exec_sid) { + new_tsec->sid = old_tsec->exec_sid; + /* Reset exec SID on execve. */ + new_tsec->exec_sid = 0; + } else { + /* Check for a default transition on this program. */ + rc = security_transition_sid(old_tsec->sid, isec->sid, + SECCLASS_PROCESS, NULL, + &new_tsec->sid); + if (rc) + return rc; + } + + COMMON_AUDIT_DATA_INIT(&ad, PATH); + ad.u.path = bprm->file->f_path; + + if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) + new_tsec->sid = old_tsec->sid; + + if (new_tsec->sid == old_tsec->sid) { + rc = avc_has_perm(old_tsec->sid, isec->sid, + SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); + if (rc) + return rc; + } else { + /* Check permissions for the transition. */ + rc = avc_has_perm(old_tsec->sid, new_tsec->sid, + SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); + if (rc) + return rc; + + rc = avc_has_perm(new_tsec->sid, isec->sid, + SECCLASS_FILE, FILE__ENTRYPOINT, &ad); + if (rc) + return rc; + + /* Check for shared state */ + if (bprm->unsafe & LSM_UNSAFE_SHARE) { + rc = avc_has_perm(old_tsec->sid, new_tsec->sid, + SECCLASS_PROCESS, PROCESS__SHARE, + NULL); + if (rc) + return -EPERM; + } + + /* Make sure that anyone attempting to ptrace over a task that + * changes its SID has the appropriate permit */ + if (bprm->unsafe & + (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { + struct task_struct *tracer; + struct task_security_struct *sec; + u32 ptsid = 0; + + rcu_read_lock(); + tracer = tracehook_tracer_task(current); + if (likely(tracer != NULL)) { + sec = __task_cred(tracer)->security; + ptsid = sec->sid; + } + rcu_read_unlock(); + + if (ptsid != 0) { + rc = avc_has_perm(ptsid, new_tsec->sid, + SECCLASS_PROCESS, + PROCESS__PTRACE, NULL); + if (rc) + return -EPERM; + } + } + + /* Clear any possibly unsafe personality bits on exec: */ + bprm->per_clear |= PER_CLEAR_ON_SETID; + } + + return 0; +} + +static int selinux_bprm_secureexec(struct linux_binprm *bprm) +{ + const struct task_security_struct *tsec = current_security(); + u32 sid, osid; + int atsecure = 0; + + sid = tsec->sid; + osid = tsec->osid; + + if (osid != sid) { + /* Enable secure mode for SIDs transitions unless + the noatsecure permission is granted between + the two SIDs, i.e. ahp returns 0. */ + atsecure = avc_has_perm(osid, sid, + SECCLASS_PROCESS, + PROCESS__NOATSECURE, NULL); + } + + return (atsecure || cap_bprm_secureexec(bprm)); +} + +extern struct vfsmount *selinuxfs_mount; +extern struct dentry *selinux_null; + +/* Derived from fs/exec.c:flush_old_files. */ +static inline void flush_unauthorized_files(const struct cred *cred, + struct files_struct *files) +{ + struct common_audit_data ad; + struct file *file, *devnull = NULL; + struct tty_struct *tty; + struct fdtable *fdt; + long j = -1; + int drop_tty = 0; + + tty = get_current_tty(); + if (tty) { + spin_lock(&tty_files_lock); + if (!list_empty(&tty->tty_files)) { + struct tty_file_private *file_priv; + struct inode *inode; + + /* Revalidate access to controlling tty. + Use inode_has_perm on the tty inode directly rather + than using file_has_perm, as this particular open + file may belong to another process and we are only + interested in the inode-based check here. */ + file_priv = list_first_entry(&tty->tty_files, + struct tty_file_private, list); + file = file_priv->file; + inode = file->f_path.dentry->d_inode; + if (inode_has_perm_noadp(cred, inode, + FILE__READ | FILE__WRITE, 0)) { + drop_tty = 1; + } + } + spin_unlock(&tty_files_lock); + tty_kref_put(tty); + } + /* Reset controlling tty. */ + if (drop_tty) + no_tty(); + + /* Revalidate access to inherited open files. */ + + COMMON_AUDIT_DATA_INIT(&ad, INODE); + + spin_lock(&files->file_lock); + for (;;) { + unsigned long set, i; + int fd; + + j++; + i = j * __NFDBITS; + fdt = files_fdtable(files); + if (i >= fdt->max_fds) + break; + set = fdt->open_fds->fds_bits[j]; + if (!set) + continue; + spin_unlock(&files->file_lock); + for ( ; set ; i++, set >>= 1) { + if (set & 1) { + file = fget(i); + if (!file) + continue; + if (file_has_perm(cred, + file, + file_to_av(file))) { + sys_close(i); + fd = get_unused_fd(); + if (fd != i) { + if (fd >= 0) + put_unused_fd(fd); + fput(file); + continue; + } + if (devnull) { + get_file(devnull); + } else { + devnull = dentry_open( + dget(selinux_null), + mntget(selinuxfs_mount), + O_RDWR, cred); + if (IS_ERR(devnull)) { + devnull = NULL; + put_unused_fd(fd); + fput(file); + continue; + } + } + fd_install(fd, devnull); + } + fput(file); + } + } + spin_lock(&files->file_lock); + + } + spin_unlock(&files->file_lock); +} + +/* + * Prepare a process for imminent new credential changes due to exec + */ +static void selinux_bprm_committing_creds(struct linux_binprm *bprm) +{ + struct task_security_struct *new_tsec; + struct rlimit *rlim, *initrlim; + int rc, i; + + new_tsec = bprm->cred->security; + if (new_tsec->sid == new_tsec->osid) + return; + + /* Close files for which the new task SID is not authorized. */ + flush_unauthorized_files(bprm->cred, current->files); + + /* Always clear parent death signal on SID transitions. */ + current->pdeath_signal = 0; + + /* Check whether the new SID can inherit resource limits from the old + * SID. If not, reset all soft limits to the lower of the current + * task's hard limit and the init task's soft limit. + * + * Note that the setting of hard limits (even to lower them) can be + * controlled by the setrlimit check. The inclusion of the init task's + * soft limit into the computation is to avoid resetting soft limits + * higher than the default soft limit for cases where the default is + * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. + */ + rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, + PROCESS__RLIMITINH, NULL); + if (rc) { + /* protect against do_prlimit() */ + task_lock(current); + for (i = 0; i < RLIM_NLIMITS; i++) { + rlim = current->signal->rlim + i; + initrlim = init_task.signal->rlim + i; + rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); + } + task_unlock(current); + update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); + } +} + +/* + * Clean up the process immediately after the installation of new credentials + * due to exec + */ +static void selinux_bprm_committed_creds(struct linux_binprm *bprm) +{ + const struct task_security_struct *tsec = current_security(); + struct itimerval itimer; + u32 osid, sid; + int rc, i; + + osid = tsec->osid; + sid = tsec->sid; + + if (sid == osid) + return; + + /* Check whether the new SID can inherit signal state from the old SID. + * If not, clear itimers to avoid subsequent signal generation and + * flush and unblock signals. + * + * This must occur _after_ the task SID has been updated so that any + * kill done after the flush will be checked against the new SID. + */ + rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); + if (rc) { + memset(&itimer, 0, sizeof itimer); + for (i = 0; i < 3; i++) + do_setitimer(i, &itimer, NULL); + spin_lock_irq(¤t->sighand->siglock); + if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { + __flush_signals(current); + flush_signal_handlers(current, 1); + sigemptyset(¤t->blocked); + } + spin_unlock_irq(¤t->sighand->siglock); + } + + /* Wake up the parent if it is waiting so that it can recheck + * wait permission to the new task SID. */ + read_lock(&tasklist_lock); + __wake_up_parent(current, current->real_parent); + read_unlock(&tasklist_lock); +} + +/* superblock security operations */ + +static int selinux_sb_alloc_security(struct super_block *sb) +{ + return superblock_alloc_security(sb); +} + +static void selinux_sb_free_security(struct super_block *sb) +{ + superblock_free_security(sb); +} + +static inline int match_prefix(char *prefix, int plen, char *option, int olen) +{ + if (plen > olen) + return 0; + + return !memcmp(prefix, option, plen); +} + +static inline int selinux_option(char *option, int len) +{ + return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || + match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || + match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || + match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || + match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); +} + +static inline void take_option(char **to, char *from, int *first, int len) +{ + if (!*first) { + **to = ','; + *to += 1; + } else + *first = 0; + memcpy(*to, from, len); + *to += len; +} + +static inline void take_selinux_option(char **to, char *from, int *first, + int len) +{ + int current_size = 0; + + if (!*first) { + **to = '|'; + *to += 1; + } else + *first = 0; + + while (current_size < len) { + if (*from != '"') { + **to = *from; + *to += 1; + } + from += 1; + current_size += 1; + } +} + +static int selinux_sb_copy_data(char *orig, char *copy) +{ + int fnosec, fsec, rc = 0; + char *in_save, *in_curr, *in_end; + char *sec_curr, *nosec_save, *nosec; + int open_quote = 0; + + in_curr = orig; + sec_curr = copy; + + nosec = (char *)get_zeroed_page(GFP_KERNEL); + if (!nosec) { + rc = -ENOMEM; + goto out; + } + + nosec_save = nosec; + fnosec = fsec = 1; + in_save = in_end = orig; + + do { + if (*in_end == '"') + open_quote = !open_quote; + if ((*in_end == ',' && open_quote == 0) || + *in_end == '\0') { + int len = in_end - in_curr; + + if (selinux_option(in_curr, len)) + take_selinux_option(&sec_curr, in_curr, &fsec, len); + else + take_option(&nosec, in_curr, &fnosec, len); + + in_curr = in_end + 1; + } + } while (*in_end++); + + strcpy(in_save, nosec_save); + free_page((unsigned long)nosec_save); +out: + return rc; +} + +static int selinux_sb_remount(struct super_block *sb, void *data) +{ + int rc, i, *flags; + struct security_mnt_opts opts; + char *secdata, **mount_options; + struct superblock_security_struct *sbsec = sb->s_security; + + if (!(sbsec->flags & SE_SBINITIALIZED)) + return 0; + + if (!data) + return 0; + + if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) + return 0; + + security_init_mnt_opts(&opts); + secdata = alloc_secdata(); + if (!secdata) + return -ENOMEM; + rc = selinux_sb_copy_data(data, secdata); + if (rc) + goto out_free_secdata; + + rc = selinux_parse_opts_str(secdata, &opts); + if (rc) + goto out_free_secdata; + + mount_options = opts.mnt_opts; + flags = opts.mnt_opts_flags; + + for (i = 0; i < opts.num_mnt_opts; i++) { + u32 sid; + size_t len; + + if (flags[i] == SE_SBLABELSUPP) + continue; + len = strlen(mount_options[i]); + rc = security_context_to_sid(mount_options[i], len, &sid); + if (rc) { + printk(KERN_WARNING "SELinux: security_context_to_sid" + "(%s) failed for (dev %s, type %s) errno=%d\n", + mount_options[i], sb->s_id, sb->s_type->name, rc); + goto out_free_opts; + } + rc = -EINVAL; + switch (flags[i]) { + case FSCONTEXT_MNT: + if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) + goto out_bad_option; + break; + case CONTEXT_MNT: + if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) + goto out_bad_option; + break; + case ROOTCONTEXT_MNT: { + struct inode_security_struct *root_isec; + root_isec = sb->s_root->d_inode->i_security; + + if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) + goto out_bad_option; + break; + } + case DEFCONTEXT_MNT: + if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) + goto out_bad_option; + break; + default: + goto out_free_opts; + } + } + + rc = 0; +out_free_opts: + security_free_mnt_opts(&opts); +out_free_secdata: + free_secdata(secdata); + return rc; +out_bad_option: + printk(KERN_WARNING "SELinux: unable to change security options " + "during remount (dev %s, type=%s)\n", sb->s_id, + sb->s_type->name); + goto out_free_opts; +} + +static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) +{ + const struct cred *cred = current_cred(); + struct common_audit_data ad; + int rc; + + rc = superblock_doinit(sb, data); + if (rc) + return rc; + + /* Allow all mounts performed by the kernel */ + if (flags & MS_KERNMOUNT) + return 0; + + COMMON_AUDIT_DATA_INIT(&ad, DENTRY); + ad.u.dentry = sb->s_root; + return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); +} + +static int selinux_sb_statfs(struct dentry *dentry) +{ + const struct cred *cred = current_cred(); + struct common_audit_data ad; + + COMMON_AUDIT_DATA_INIT(&ad, DENTRY); + ad.u.dentry = dentry->d_sb->s_root; + return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); +} + +static int selinux_mount(char *dev_name, + struct path *path, + char *type, + unsigned long flags, + void *data) +{ + const struct cred *cred = current_cred(); + + if (flags & MS_REMOUNT) + return superblock_has_perm(cred, path->mnt->mnt_sb, + FILESYSTEM__REMOUNT, NULL); + else + return path_has_perm(cred, path, FILE__MOUNTON); +} + +static int selinux_umount(struct vfsmount *mnt, int flags) +{ + const struct cred *cred = current_cred(); + + return superblock_has_perm(cred, mnt->mnt_sb, + FILESYSTEM__UNMOUNT, NULL); +} + +/* inode security operations */ + +static int selinux_inode_alloc_security(struct inode *inode) +{ + return inode_alloc_security(inode); +} + +static void selinux_inode_free_security(struct inode *inode) +{ + inode_free_security(inode); +} + +static int selinux_inode_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr, char **name, + void **value, size_t *len) +{ + const struct task_security_struct *tsec = current_security(); + struct inode_security_struct *dsec; + struct superblock_security_struct *sbsec; + u32 sid, newsid, clen; + int rc; + char *namep = NULL, *context; + + dsec = dir->i_security; + sbsec = dir->i_sb->s_security; + + sid = tsec->sid; + newsid = tsec->create_sid; + + if ((sbsec->flags & SE_SBINITIALIZED) && + (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) + newsid = sbsec->mntpoint_sid; + else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { + rc = security_transition_sid(sid, dsec->sid, + inode_mode_to_security_class(inode->i_mode), + qstr, &newsid); + if (rc) { + printk(KERN_WARNING "%s: " + "security_transition_sid failed, rc=%d (dev=%s " + "ino=%ld)\n", + __func__, + -rc, inode->i_sb->s_id, inode->i_ino); + return rc; + } + } + + /* Possibly defer initialization to selinux_complete_init. */ + if (sbsec->flags & SE_SBINITIALIZED) { + struct inode_security_struct *isec = inode->i_security; + isec->sclass = inode_mode_to_security_class(inode->i_mode); + isec->sid = newsid; + isec->initialized = 1; + } + + if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) + return -EOPNOTSUPP; + + if (name) { + namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); + if (!namep) + return -ENOMEM; + *name = namep; + } + + if (value && len) { + rc = security_sid_to_context_force(newsid, &context, &clen); + if (rc) { + kfree(namep); + return rc; + } + *value = context; + *len = clen; + } + + return 0; +} + +static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) +{ + return may_create(dir, dentry, SECCLASS_FILE); +} + +static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) +{ + return may_link(dir, old_dentry, MAY_LINK); +} + +static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) +{ + return may_link(dir, dentry, MAY_UNLINK); +} + +static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) +{ + return may_create(dir, dentry, SECCLASS_LNK_FILE); +} + +static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) +{ + return may_create(dir, dentry, SECCLASS_DIR); +} + +static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) +{ + return may_link(dir, dentry, MAY_RMDIR); +} + +static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) +{ + return may_create(dir, dentry, inode_mode_to_security_class(mode)); +} + +static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, + struct inode *new_inode, struct dentry *new_dentry) +{ + return may_rename(old_inode, old_dentry, new_inode, new_dentry); +} + +static int selinux_inode_readlink(struct dentry *dentry) +{ + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, dentry, FILE__READ); +} + +static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) +{ + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, dentry, FILE__READ); +} + +static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags) +{ + const struct cred *cred = current_cred(); + struct common_audit_data ad; + u32 perms; + bool from_access; + + from_access = mask & MAY_ACCESS; + mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); + + /* No permission to check. Existence test. */ + if (!mask) + return 0; + + COMMON_AUDIT_DATA_INIT(&ad, INODE); + ad.u.inode = inode; + + if (from_access) + ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS; + + perms = file_mask_to_av(inode->i_mode, mask); + + return inode_has_perm(cred, inode, perms, &ad, flags); +} + +static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) +{ + const struct cred *cred = current_cred(); + unsigned int ia_valid = iattr->ia_valid; + + /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ + if (ia_valid & ATTR_FORCE) { + ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | + ATTR_FORCE); + if (!ia_valid) + return 0; + } + + if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | + ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) + return dentry_has_perm(cred, dentry, FILE__SETATTR); + + return dentry_has_perm(cred, dentry, FILE__WRITE); +} + +static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) +{ + const struct cred *cred = current_cred(); + struct path path; + + path.dentry = dentry; + path.mnt = mnt; + + return path_has_perm(cred, &path, FILE__GETATTR); +} + +static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) +{ + const struct cred *cred = current_cred(); + + if (!strncmp(name, XATTR_SECURITY_PREFIX, + sizeof XATTR_SECURITY_PREFIX - 1)) { + if (!strcmp(name, XATTR_NAME_CAPS)) { + if (!capable(CAP_SETFCAP)) + return -EPERM; + } else if (!capable(CAP_SYS_ADMIN)) { + /* A different attribute in the security namespace. + Restrict to administrator. */ + return -EPERM; + } + } + + /* Not an attribute we recognize, so just check the + ordinary setattr permission. */ + return dentry_has_perm(cred, dentry, FILE__SETATTR); +} + +static int selinux_inode_setxattr(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags) +{ + struct inode *inode = dentry->d_inode; + struct inode_security_struct *isec = inode->i_security; + struct superblock_security_struct *sbsec; + struct common_audit_data ad; + u32 newsid, sid = current_sid(); + int rc = 0; + + if (strcmp(name, XATTR_NAME_SELINUX)) + return selinux_inode_setotherxattr(dentry, name); + + sbsec = inode->i_sb->s_security; + if (!(sbsec->flags & SE_SBLABELSUPP)) + return -EOPNOTSUPP; + + if (!inode_owner_or_capable(inode)) + return -EPERM; + + COMMON_AUDIT_DATA_INIT(&ad, DENTRY); + ad.u.dentry = dentry; + + rc = avc_has_perm(sid, isec->sid, isec->sclass, + FILE__RELABELFROM, &ad); + if (rc) + return rc; + + rc = security_context_to_sid(value, size, &newsid); + if (rc == -EINVAL) { + if (!capable(CAP_MAC_ADMIN)) + return rc; + rc = security_context_to_sid_force(value, size, &newsid); + } + if (rc) + return rc; + + rc = avc_has_perm(sid, newsid, isec->sclass, + FILE__RELABELTO, &ad); + if (rc) + return rc; + + rc = security_validate_transition(isec->sid, newsid, sid, + isec->sclass); + if (rc) + return rc; + + return avc_has_perm(newsid, + sbsec->sid, + SECCLASS_FILESYSTEM, + FILESYSTEM__ASSOCIATE, + &ad); +} + +static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, + const void *value, size_t size, + int flags) +{ + struct inode *inode = dentry->d_inode; + struct inode_security_struct *isec = inode->i_security; + u32 newsid; + int rc; + + if (strcmp(name, XATTR_NAME_SELINUX)) { + /* Not an attribute we recognize, so nothing to do. */ + return; + } + + rc = security_context_to_sid_force(value, size, &newsid); + if (rc) { + printk(KERN_ERR "SELinux: unable to map context to SID" + "for (%s, %lu), rc=%d\n", + inode->i_sb->s_id, inode->i_ino, -rc); + return; + } + + isec->sid = newsid; + return; +} + +static int selinux_inode_getxattr(struct dentry *dentry, const char *name) +{ + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, dentry, FILE__GETATTR); +} + +static int selinux_inode_listxattr(struct dentry *dentry) +{ + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, dentry, FILE__GETATTR); +} + +static int selinux_inode_removexattr(struct dentry *dentry, const char *name) +{ + if (strcmp(name, XATTR_NAME_SELINUX)) + return selinux_inode_setotherxattr(dentry, name); + + /* No one is allowed to remove a SELinux security label. + You can change the label, but all data must be labeled. */ + return -EACCES; +} + +/* + * Copy the inode security context value to the user. + * + * Permission check is handled by selinux_inode_getxattr hook. + */ +static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) +{ + u32 size; + int error; + char *context = NULL; + struct inode_security_struct *isec = inode->i_security; + + if (strcmp(name, XATTR_SELINUX_SUFFIX)) + return -EOPNOTSUPP; + + /* + * If the caller has CAP_MAC_ADMIN, then get the raw context + * value even if it is not defined by current policy; otherwise, + * use the in-core value under current policy. + * Use the non-auditing forms of the permission checks since + * getxattr may be called by unprivileged processes commonly + * and lack of permission just means that we fall back to the + * in-core context value, not a denial. + */ + error = selinux_capable(current, current_cred(), + &init_user_ns, CAP_MAC_ADMIN, + SECURITY_CAP_NOAUDIT); + if (!error) + error = security_sid_to_context_force(isec->sid, &context, + &size); + else + error = security_sid_to_context(isec->sid, &context, &size); + if (error) + return error; + error = size; + if (alloc) { + *buffer = context; + goto out_nofree; + } + kfree(context); +out_nofree: + return error; +} + +static int selinux_inode_setsecurity(struct inode *inode, const char *name, + const void *value, size_t size, int flags) +{ + struct inode_security_struct *isec = inode->i_security; + u32 newsid; + int rc; + + if (strcmp(name, XATTR_SELINUX_SUFFIX)) + return -EOPNOTSUPP; + + if (!value || !size) + return -EACCES; + + rc = security_context_to_sid((void *)value, size, &newsid); + if (rc) + return rc; + + isec->sid = newsid; + isec->initialized = 1; + return 0; +} + +static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) +{ + const int len = sizeof(XATTR_NAME_SELINUX); + if (buffer && len <= buffer_size) + memcpy(buffer, XATTR_NAME_SELINUX, len); + return len; +} + +static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) +{ + struct inode_security_struct *isec = inode->i_security; + *secid = isec->sid; +} + +/* file security operations */ + +static int selinux_revalidate_file_permission(struct file *file, int mask) +{ + const struct cred *cred = current_cred(); + struct inode *inode = file->f_path.dentry->d_inode; + + /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ + if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) + mask |= MAY_APPEND; + + return file_has_perm(cred, file, + file_mask_to_av(inode->i_mode, mask)); +} + +static int selinux_file_permission(struct file *file, int mask) +{ + struct inode *inode = file->f_path.dentry->d_inode; + struct file_security_struct *fsec = file->f_security; + struct inode_security_struct *isec = inode->i_security; + u32 sid = current_sid(); + + if (!mask) + /* No permission to check. Existence test. */ + return 0; + + if (sid == fsec->sid && fsec->isid == isec->sid && + fsec->pseqno == avc_policy_seqno()) + /* No change since dentry_open check. */ + return 0; + + return selinux_revalidate_file_permission(file, mask); +} + +static int selinux_file_alloc_security(struct file *file) +{ + return file_alloc_security(file); +} + +static void selinux_file_free_security(struct file *file) +{ + file_free_security(file); +} + +static int selinux_file_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + const struct cred *cred = current_cred(); + int error = 0; + + switch (cmd) { + case FIONREAD: + /* fall through */ + case FIBMAP: + /* fall through */ + case FIGETBSZ: + /* fall through */ + case EXT2_IOC_GETFLAGS: + /* fall through */ + case EXT2_IOC_GETVERSION: + error = file_has_perm(cred, file, FILE__GETATTR); + break; + + case EXT2_IOC_SETFLAGS: + /* fall through */ + case EXT2_IOC_SETVERSION: + error = file_has_perm(cred, file, FILE__SETATTR); + break; + + /* sys_ioctl() checks */ + case FIONBIO: + /* fall through */ + case FIOASYNC: + error = file_has_perm(cred, file, 0); + break; + + case KDSKBENT: + case KDSKBSENT: + error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG, + SECURITY_CAP_AUDIT); + break; + + /* default case assumes that the command will go + * to the file's ioctl() function. + */ + default: + error = file_has_perm(cred, file, FILE__IOCTL); + } + return error; +} + +static int default_noexec; + +static int file_map_prot_check(struct file *file, unsigned long prot, int shared) +{ + const struct cred *cred = current_cred(); + int rc = 0; + + if (default_noexec && + (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { + /* + * We are making executable an anonymous mapping or a + * private file mapping that will also be writable. + * This has an additional check. + */ + rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); + if (rc) + goto error; + } + + if (file) { + /* read access is always possible with a mapping */ + u32 av = FILE__READ; + + /* write access only matters if the mapping is shared */ + if (shared && (prot & PROT_WRITE)) + av |= FILE__WRITE; + + if (prot & PROT_EXEC) + av |= FILE__EXECUTE; + + return file_has_perm(cred, file, av); + } + +error: + return rc; +} + +static int selinux_file_mmap(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags, + unsigned long addr, unsigned long addr_only) +{ + int rc = 0; + u32 sid = current_sid(); + + /* + * notice that we are intentionally putting the SELinux check before + * the secondary cap_file_mmap check. This is such a likely attempt + * at bad behaviour/exploit that we always want to get the AVC, even + * if DAC would have also denied the operation. + */ + if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { + rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, + MEMPROTECT__MMAP_ZERO, NULL); + if (rc) + return rc; + } + + /* do DAC check on address space usage */ + rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); + if (rc || addr_only) + return rc; + + if (selinux_checkreqprot) + prot = reqprot; + + return file_map_prot_check(file, prot, + (flags & MAP_TYPE) == MAP_SHARED); +} + +static int selinux_file_mprotect(struct vm_area_struct *vma, + unsigned long reqprot, + unsigned long prot) +{ + const struct cred *cred = current_cred(); + + if (selinux_checkreqprot) + prot = reqprot; + + if (default_noexec && + (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { + int rc = 0; + if (vma->vm_start >= vma->vm_mm->start_brk && + vma->vm_end <= vma->vm_mm->brk) { + rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); + } else if (!vma->vm_file && + vma->vm_start <= vma->vm_mm->start_stack && + vma->vm_end >= vma->vm_mm->start_stack) { + rc = current_has_perm(current, PROCESS__EXECSTACK); + } else if (vma->vm_file && vma->anon_vma) { + /* + * We are making executable a file mapping that has + * had some COW done. Since pages might have been + * written, check ability to execute the possibly + * modified content. This typically should only + * occur for text relocations. + */ + rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); + } + if (rc) + return rc; + } + + return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); +} + +static int selinux_file_lock(struct file *file, unsigned int cmd) +{ + const struct cred *cred = current_cred(); + + return file_has_perm(cred, file, FILE__LOCK); +} + +static int selinux_file_fcntl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + const struct cred *cred = current_cred(); + int err = 0; + + switch (cmd) { + case F_SETFL: + if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { + err = -EINVAL; + break; + } + + if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { + err = file_has_perm(cred, file, FILE__WRITE); + break; + } + /* fall through */ + case F_SETOWN: + case F_SETSIG: + case F_GETFL: + case F_GETOWN: + case F_GETSIG: + /* Just check FD__USE permission */ + err = file_has_perm(cred, file, 0); + break; + case F_GETLK: + case F_SETLK: + case F_SETLKW: +#if BITS_PER_LONG == 32 + case F_GETLK64: + case F_SETLK64: + case F_SETLKW64: +#endif + if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { + err = -EINVAL; + break; + } + err = file_has_perm(cred, file, FILE__LOCK); + break; + } + + return err; +} + +static int selinux_file_set_fowner(struct file *file) +{ + struct file_security_struct *fsec; + + fsec = file->f_security; + fsec->fown_sid = current_sid(); + + return 0; +} + +static int selinux_file_send_sigiotask(struct task_struct *tsk, + struct fown_struct *fown, int signum) +{ + struct file *file; + u32 sid = task_sid(tsk); + u32 perm; + struct file_security_struct *fsec; + + /* struct fown_struct is never outside the context of a struct file */ + file = container_of(fown, struct file, f_owner); + + fsec = file->f_security; + + if (!signum) + perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ + else + perm = signal_to_av(signum); + + return avc_has_perm(fsec->fown_sid, sid, + SECCLASS_PROCESS, perm, NULL); +} + +static int selinux_file_receive(struct file *file) +{ + const struct cred *cred = current_cred(); + + return file_has_perm(cred, file, file_to_av(file)); +} + +static int selinux_dentry_open(struct file *file, const struct cred *cred) +{ + struct file_security_struct *fsec; + struct inode *inode; + struct inode_security_struct *isec; + + inode = file->f_path.dentry->d_inode; + fsec = file->f_security; + isec = inode->i_security; + /* + * Save inode label and policy sequence number + * at open-time so that selinux_file_permission + * can determine whether revalidation is necessary. + * Task label is already saved in the file security + * struct as its SID. + */ + fsec->isid = isec->sid; + fsec->pseqno = avc_policy_seqno(); + /* + * Since the inode label or policy seqno may have changed + * between the selinux_inode_permission check and the saving + * of state above, recheck that access is still permitted. + * Otherwise, access might never be revalidated against the + * new inode label or new policy. + * This check is not redundant - do not remove. + */ + return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0); +} + +/* task security operations */ + +static int selinux_task_create(unsigned long clone_flags) +{ + return current_has_perm(current, PROCESS__FORK); +} + +/* + * allocate the SELinux part of blank credentials + */ +static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) +{ + struct task_security_struct *tsec; + + tsec = kzalloc(sizeof(struct task_security_struct), gfp); + if (!tsec) + return -ENOMEM; + + cred->security = tsec; + return 0; +} + +/* + * detach and free the LSM part of a set of credentials + */ +static void selinux_cred_free(struct cred *cred) +{ + struct task_security_struct *tsec = cred->security; + + /* + * cred->security == NULL if security_cred_alloc_blank() or + * security_prepare_creds() returned an error. + */ + BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); + cred->security = (void *) 0x7UL; + kfree(tsec); +} + +/* + * prepare a new set of credentials for modification + */ +static int selinux_cred_prepare(struct cred *new, const struct cred *old, + gfp_t gfp) +{ + const struct task_security_struct *old_tsec; + struct task_security_struct *tsec; + + old_tsec = old->security; + + tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); + if (!tsec) + return -ENOMEM; + + new->security = tsec; + return 0; +} + +/* + * transfer the SELinux data to a blank set of creds + */ +static void selinux_cred_transfer(struct cred *new, const struct cred *old) +{ + const struct task_security_struct *old_tsec = old->security; + struct task_security_struct *tsec = new->security; + + *tsec = *old_tsec; +} + +/* + * set the security data for a kernel service + * - all the creation contexts are set to unlabelled + */ +static int selinux_kernel_act_as(struct cred *new, u32 secid) +{ + struct task_security_struct *tsec = new->security; + u32 sid = current_sid(); + int ret; + + ret = avc_has_perm(sid, secid, + SECCLASS_KERNEL_SERVICE, + KERNEL_SERVICE__USE_AS_OVERRIDE, + NULL); + if (ret == 0) { + tsec->sid = secid; + tsec->create_sid = 0; + tsec->keycreate_sid = 0; + tsec->sockcreate_sid = 0; + } + return ret; +} + +/* + * set the file creation context in a security record to the same as the + * objective context of the specified inode + */ +static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) +{ + struct inode_security_struct *isec = inode->i_security; + struct task_security_struct *tsec = new->security; + u32 sid = current_sid(); + int ret; + + ret = avc_has_perm(sid, isec->sid, + SECCLASS_KERNEL_SERVICE, + KERNEL_SERVICE__CREATE_FILES_AS, + NULL); + + if (ret == 0) + tsec->create_sid = isec->sid; + return ret; +} + +static int selinux_kernel_module_request(char *kmod_name) +{ + u32 sid; + struct common_audit_data ad; + + sid = task_sid(current); + + COMMON_AUDIT_DATA_INIT(&ad, KMOD); + ad.u.kmod_name = kmod_name; + + return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, + SYSTEM__MODULE_REQUEST, &ad); +} + +static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) +{ + return current_has_perm(p, PROCESS__SETPGID); +} + +static int selinux_task_getpgid(struct task_struct *p) +{ + return current_has_perm(p, PROCESS__GETPGID); +} + +static int selinux_task_getsid(struct task_struct *p) +{ + return current_has_perm(p, PROCESS__GETSESSION); +} + +static void selinux_task_getsecid(struct task_struct *p, u32 *secid) +{ + *secid = task_sid(p); +} + +static int selinux_task_setnice(struct task_struct *p, int nice) +{ + int rc; + + rc = cap_task_setnice(p, nice); + if (rc) + return rc; + + return current_has_perm(p, PROCESS__SETSCHED); +} + +static int selinux_task_setioprio(struct task_struct *p, int ioprio) +{ + int rc; + + rc = cap_task_setioprio(p, ioprio); + if (rc) + return rc; + + return current_has_perm(p, PROCESS__SETSCHED); +} + +static int selinux_task_getioprio(struct task_struct *p) +{ + return current_has_perm(p, PROCESS__GETSCHED); +} + +static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, + struct rlimit *new_rlim) +{ + struct rlimit *old_rlim = p->signal->rlim + resource; + + /* Control the ability to change the hard limit (whether + lowering or raising it), so that the hard limit can + later be used as a safe reset point for the soft limit + upon context transitions. See selinux_bprm_committing_creds. */ + if (old_rlim->rlim_max != new_rlim->rlim_max) + return current_has_perm(p, PROCESS__SETRLIMIT); + + return 0; +} + +static int selinux_task_setscheduler(struct task_struct *p) +{ + int rc; + + rc = cap_task_setscheduler(p); + if (rc) + return rc; + + return current_has_perm(p, PROCESS__SETSCHED); +} + +static int selinux_task_getscheduler(struct task_struct *p) +{ + return current_has_perm(p, PROCESS__GETSCHED); +} + +static int selinux_task_movememory(struct task_struct *p) +{ + return current_has_perm(p, PROCESS__SETSCHED); +} + +static int selinux_task_kill(struct task_struct *p, struct siginfo *info, + int sig, u32 secid) +{ + u32 perm; + int rc; + + if (!sig) + perm = PROCESS__SIGNULL; /* null signal; existence test */ + else + perm = signal_to_av(sig); + if (secid) + rc = avc_has_perm(secid, task_sid(p), + SECCLASS_PROCESS, perm, NULL); + else + rc = current_has_perm(p, perm); + return rc; +} + +static int selinux_task_wait(struct task_struct *p) +{ + return task_has_perm(p, current, PROCESS__SIGCHLD); +} + +static void selinux_task_to_inode(struct task_struct *p, + struct inode *inode) +{ + struct inode_security_struct *isec = inode->i_security; + u32 sid = task_sid(p); + + isec->sid = sid; + isec->initialized = 1; +} + +/* Returns error only if unable to parse addresses */ +static int selinux_parse_skb_ipv4(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto) +{ + int offset, ihlen, ret = -EINVAL; + struct iphdr _iph, *ih; + + offset = skb_network_offset(skb); + ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); + if (ih == NULL) + goto out; + + ihlen = ih->ihl * 4; + if (ihlen < sizeof(_iph)) + goto out; + + ad->u.net.v4info.saddr = ih->saddr; + ad->u.net.v4info.daddr = ih->daddr; + ret = 0; + + if (proto) + *proto = ih->protocol; + + switch (ih->protocol) { + case IPPROTO_TCP: { + struct tcphdr _tcph, *th; + + if (ntohs(ih->frag_off) & IP_OFFSET) + break; + + offset += ihlen; + th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); + if (th == NULL) + break; + + ad->u.net.sport = th->source; + ad->u.net.dport = th->dest; + break; + } + + case IPPROTO_UDP: { + struct udphdr _udph, *uh; + + if (ntohs(ih->frag_off) & IP_OFFSET) + break; + + offset += ihlen; + uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); + if (uh == NULL) + break; + + ad->u.net.sport = uh->source; + ad->u.net.dport = uh->dest; + break; + } + + case IPPROTO_DCCP: { + struct dccp_hdr _dccph, *dh; + + if (ntohs(ih->frag_off) & IP_OFFSET) + break; + + offset += ihlen; + dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); + if (dh == NULL) + break; + + ad->u.net.sport = dh->dccph_sport; + ad->u.net.dport = dh->dccph_dport; + break; + } + + default: + break; + } +out: + return ret; +} + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) + +/* Returns error only if unable to parse addresses */ +static int selinux_parse_skb_ipv6(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto) +{ + u8 nexthdr; + int ret = -EINVAL, offset; + struct ipv6hdr _ipv6h, *ip6; + + offset = skb_network_offset(skb); + ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); + if (ip6 == NULL) + goto out; + + ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); + ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); + ret = 0; + + nexthdr = ip6->nexthdr; + offset += sizeof(_ipv6h); + offset = ipv6_skip_exthdr(skb, offset, &nexthdr); + if (offset < 0) + goto out; + + if (proto) + *proto = nexthdr; + + switch (nexthdr) { + case IPPROTO_TCP: { + struct tcphdr _tcph, *th; + + th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); + if (th == NULL) + break; + + ad->u.net.sport = th->source; + ad->u.net.dport = th->dest; + break; + } + + case IPPROTO_UDP: { + struct udphdr _udph, *uh; + + uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); + if (uh == NULL) + break; + + ad->u.net.sport = uh->source; + ad->u.net.dport = uh->dest; + break; + } + + case IPPROTO_DCCP: { + struct dccp_hdr _dccph, *dh; + + dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); + if (dh == NULL) + break; + + ad->u.net.sport = dh->dccph_sport; + ad->u.net.dport = dh->dccph_dport; + break; + } + + /* includes fragments */ + default: + break; + } +out: + return ret; +} + +#endif /* IPV6 */ + +static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, + char **_addrp, int src, u8 *proto) +{ + char *addrp; + int ret; + + switch (ad->u.net.family) { + case PF_INET: + ret = selinux_parse_skb_ipv4(skb, ad, proto); + if (ret) + goto parse_error; + addrp = (char *)(src ? &ad->u.net.v4info.saddr : + &ad->u.net.v4info.daddr); + goto okay; + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) + case PF_INET6: + ret = selinux_parse_skb_ipv6(skb, ad, proto); + if (ret) + goto parse_error; + addrp = (char *)(src ? &ad->u.net.v6info.saddr : + &ad->u.net.v6info.daddr); + goto okay; +#endif /* IPV6 */ + default: + addrp = NULL; + goto okay; + } + +parse_error: + printk(KERN_WARNING + "SELinux: failure in selinux_parse_skb()," + " unable to parse packet\n"); + return ret; + +okay: + if (_addrp) + *_addrp = addrp; + return 0; +} + +/** + * selinux_skb_peerlbl_sid - Determine the peer label of a packet + * @skb: the packet + * @family: protocol family + * @sid: the packet's peer label SID + * + * Description: + * Check the various different forms of network peer labeling and determine + * the peer label/SID for the packet; most of the magic actually occurs in + * the security server function security_net_peersid_cmp(). The function + * returns zero if the value in @sid is valid (although it may be SECSID_NULL) + * or -EACCES if @sid is invalid due to inconsistencies with the different + * peer labels. + * + */ +static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) +{ + int err; + u32 xfrm_sid; + u32 nlbl_sid; + u32 nlbl_type; + + selinux_skb_xfrm_sid(skb, &xfrm_sid); + selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); + + err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); + if (unlikely(err)) { + printk(KERN_WARNING + "SELinux: failure in selinux_skb_peerlbl_sid()," + " unable to determine packet's peer label\n"); + return -EACCES; + } + + return 0; +} + +/* socket security operations */ + +static int socket_sockcreate_sid(const struct task_security_struct *tsec, + u16 secclass, u32 *socksid) +{ + if (tsec->sockcreate_sid > SECSID_NULL) { + *socksid = tsec->sockcreate_sid; + return 0; + } + + return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, + socksid); +} + +static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) +{ + struct sk_security_struct *sksec = sk->sk_security; + struct common_audit_data ad; + u32 tsid = task_sid(task); + + if (sksec->sid == SECINITSID_KERNEL) + return 0; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.sk = sk; + + return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); +} + +static int selinux_socket_create(int family, int type, + int protocol, int kern) +{ + const struct task_security_struct *tsec = current_security(); + u32 newsid; + u16 secclass; + int rc; + + if (kern) + return 0; + + secclass = socket_type_to_security_class(family, type, protocol); + rc = socket_sockcreate_sid(tsec, secclass, &newsid); + if (rc) + return rc; + + return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); +} + +static int selinux_socket_post_create(struct socket *sock, int family, + int type, int protocol, int kern) +{ + const struct task_security_struct *tsec = current_security(); + struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; + struct sk_security_struct *sksec; + int err = 0; + + isec->sclass = socket_type_to_security_class(family, type, protocol); + + if (kern) + isec->sid = SECINITSID_KERNEL; + else { + err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid)); + if (err) + return err; + } + + isec->initialized = 1; + + if (sock->sk) { + sksec = sock->sk->sk_security; + sksec->sid = isec->sid; + sksec->sclass = isec->sclass; + err = selinux_netlbl_socket_post_create(sock->sk, family); + } + + return err; +} + +/* Range of port numbers used to automatically bind. + Need to determine whether we should perform a name_bind + permission check between the socket and the port number. */ + +static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) +{ + struct sock *sk = sock->sk; + u16 family; + int err; + + err = sock_has_perm(current, sk, SOCKET__BIND); + if (err) + goto out; + + /* + * If PF_INET or PF_INET6, check name_bind permission for the port. + * Multiple address binding for SCTP is not supported yet: we just + * check the first address now. + */ + family = sk->sk_family; + if (family == PF_INET || family == PF_INET6) { + char *addrp; + struct sk_security_struct *sksec = sk->sk_security; + struct common_audit_data ad; + struct sockaddr_in *addr4 = NULL; + struct sockaddr_in6 *addr6 = NULL; + unsigned short snum; + u32 sid, node_perm; + + if (family == PF_INET) { + addr4 = (struct sockaddr_in *)address; + snum = ntohs(addr4->sin_port); + addrp = (char *)&addr4->sin_addr.s_addr; + } else { + addr6 = (struct sockaddr_in6 *)address; + snum = ntohs(addr6->sin6_port); + addrp = (char *)&addr6->sin6_addr.s6_addr; + } + + if (snum) { + int low, high; + + inet_get_local_port_range(&low, &high); + + if (snum < max(PROT_SOCK, low) || snum > high) { + err = sel_netport_sid(sk->sk_protocol, + snum, &sid); + if (err) + goto out; + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.sport = htons(snum); + ad.u.net.family = family; + err = avc_has_perm(sksec->sid, sid, + sksec->sclass, + SOCKET__NAME_BIND, &ad); + if (err) + goto out; + } + } + + switch (sksec->sclass) { + case SECCLASS_TCP_SOCKET: + node_perm = TCP_SOCKET__NODE_BIND; + break; + + case SECCLASS_UDP_SOCKET: + node_perm = UDP_SOCKET__NODE_BIND; + break; + + case SECCLASS_DCCP_SOCKET: + node_perm = DCCP_SOCKET__NODE_BIND; + break; + + default: + node_perm = RAWIP_SOCKET__NODE_BIND; + break; + } + + err = sel_netnode_sid(addrp, family, &sid); + if (err) + goto out; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.sport = htons(snum); + ad.u.net.family = family; + + if (family == PF_INET) + ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; + else + ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); + + err = avc_has_perm(sksec->sid, sid, + sksec->sclass, node_perm, &ad); + if (err) + goto out; + } +out: + return err; +} + +static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) +{ + struct sock *sk = sock->sk; + struct sk_security_struct *sksec = sk->sk_security; + int err; + + err = sock_has_perm(current, sk, SOCKET__CONNECT); + if (err) + return err; + + /* + * If a TCP or DCCP socket, check name_connect permission for the port. + */ + if (sksec->sclass == SECCLASS_TCP_SOCKET || + sksec->sclass == SECCLASS_DCCP_SOCKET) { + struct common_audit_data ad; + struct sockaddr_in *addr4 = NULL; + struct sockaddr_in6 *addr6 = NULL; + unsigned short snum; + u32 sid, perm; + + if (sk->sk_family == PF_INET) { + addr4 = (struct sockaddr_in *)address; + if (addrlen < sizeof(struct sockaddr_in)) + return -EINVAL; + snum = ntohs(addr4->sin_port); + } else { + addr6 = (struct sockaddr_in6 *)address; + if (addrlen < SIN6_LEN_RFC2133) + return -EINVAL; + snum = ntohs(addr6->sin6_port); + } + + err = sel_netport_sid(sk->sk_protocol, snum, &sid); + if (err) + goto out; + + perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? + TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.dport = htons(snum); + ad.u.net.family = sk->sk_family; + err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); + if (err) + goto out; + } + + err = selinux_netlbl_socket_connect(sk, address); + +out: + return err; +} + +static int selinux_socket_listen(struct socket *sock, int backlog) +{ + return sock_has_perm(current, sock->sk, SOCKET__LISTEN); +} + +static int selinux_socket_accept(struct socket *sock, struct socket *newsock) +{ + int err; + struct inode_security_struct *isec; + struct inode_security_struct *newisec; + + err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); + if (err) + return err; + + newisec = SOCK_INODE(newsock)->i_security; + + isec = SOCK_INODE(sock)->i_security; + newisec->sclass = isec->sclass; + newisec->sid = isec->sid; + newisec->initialized = 1; + + return 0; +} + +static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, + int size) +{ + return sock_has_perm(current, sock->sk, SOCKET__WRITE); +} + +static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, + int size, int flags) +{ + return sock_has_perm(current, sock->sk, SOCKET__READ); +} + +static int selinux_socket_getsockname(struct socket *sock) +{ + return sock_has_perm(current, sock->sk, SOCKET__GETATTR); +} + +static int selinux_socket_getpeername(struct socket *sock) +{ + return sock_has_perm(current, sock->sk, SOCKET__GETATTR); +} + +static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) +{ + int err; + + err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); + if (err) + return err; + + return selinux_netlbl_socket_setsockopt(sock, level, optname); +} + +static int selinux_socket_getsockopt(struct socket *sock, int level, + int optname) +{ + return sock_has_perm(current, sock->sk, SOCKET__GETOPT); +} + +static int selinux_socket_shutdown(struct socket *sock, int how) +{ + return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); +} + +static int selinux_socket_unix_stream_connect(struct sock *sock, + struct sock *other, + struct sock *newsk) +{ + struct sk_security_struct *sksec_sock = sock->sk_security; + struct sk_security_struct *sksec_other = other->sk_security; + struct sk_security_struct *sksec_new = newsk->sk_security; + struct common_audit_data ad; + int err; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.sk = other; + + err = avc_has_perm(sksec_sock->sid, sksec_other->sid, + sksec_other->sclass, + UNIX_STREAM_SOCKET__CONNECTTO, &ad); + if (err) + return err; + + /* server child socket */ + sksec_new->peer_sid = sksec_sock->sid; + err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, + &sksec_new->sid); + if (err) + return err; + + /* connecting socket */ + sksec_sock->peer_sid = sksec_new->sid; + + return 0; +} + +static int selinux_socket_unix_may_send(struct socket *sock, + struct socket *other) +{ + struct sk_security_struct *ssec = sock->sk->sk_security; + struct sk_security_struct *osec = other->sk->sk_security; + struct common_audit_data ad; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.sk = other->sk; + + return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, + &ad); +} + +static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, + u32 peer_sid, + struct common_audit_data *ad) +{ + int err; + u32 if_sid; + u32 node_sid; + + err = sel_netif_sid(ifindex, &if_sid); + if (err) + return err; + err = avc_has_perm(peer_sid, if_sid, + SECCLASS_NETIF, NETIF__INGRESS, ad); + if (err) + return err; + + err = sel_netnode_sid(addrp, family, &node_sid); + if (err) + return err; + return avc_has_perm(peer_sid, node_sid, + SECCLASS_NODE, NODE__RECVFROM, ad); +} + +static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, + u16 family) +{ + int err = 0; + struct sk_security_struct *sksec = sk->sk_security; + u32 sk_sid = sksec->sid; + struct common_audit_data ad; + char *addrp; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.netif = skb->skb_iif; + ad.u.net.family = family; + err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); + if (err) + return err; + + if (selinux_secmark_enabled()) { + err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, + PACKET__RECV, &ad); + if (err) + return err; + } + + err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); + if (err) + return err; + err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); + + return err; +} + +static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) +{ + int err; + struct sk_security_struct *sksec = sk->sk_security; + u16 family = sk->sk_family; + u32 sk_sid = sksec->sid; + struct common_audit_data ad; + char *addrp; + u8 secmark_active; + u8 peerlbl_active; + + if (family != PF_INET && family != PF_INET6) + return 0; + + /* Handle mapped IPv4 packets arriving via IPv6 sockets */ + if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) + family = PF_INET; + + /* If any sort of compatibility mode is enabled then handoff processing + * to the selinux_sock_rcv_skb_compat() function to deal with the + * special handling. We do this in an attempt to keep this function + * as fast and as clean as possible. */ + if (!selinux_policycap_netpeer) + return selinux_sock_rcv_skb_compat(sk, skb, family); + + secmark_active = selinux_secmark_enabled(); + peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); + if (!secmark_active && !peerlbl_active) + return 0; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.netif = skb->skb_iif; + ad.u.net.family = family; + err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); + if (err) + return err; + + if (peerlbl_active) { + u32 peer_sid; + + err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); + if (err) + return err; + err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family, + peer_sid, &ad); + if (err) { + selinux_netlbl_err(skb, err, 0); + return err; + } + err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, + PEER__RECV, &ad); + if (err) + selinux_netlbl_err(skb, err, 0); + } + + if (secmark_active) { + err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, + PACKET__RECV, &ad); + if (err) + return err; + } + + return err; +} + +static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, + int __user *optlen, unsigned len) +{ + int err = 0; + char *scontext; + u32 scontext_len; + struct sk_security_struct *sksec = sock->sk->sk_security; + u32 peer_sid = SECSID_NULL; + + if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || + sksec->sclass == SECCLASS_TCP_SOCKET) + peer_sid = sksec->peer_sid; + if (peer_sid == SECSID_NULL) + return -ENOPROTOOPT; + + err = security_sid_to_context(peer_sid, &scontext, &scontext_len); + if (err) + return err; + + if (scontext_len > len) { + err = -ERANGE; + goto out_len; + } + + if (copy_to_user(optval, scontext, scontext_len)) + err = -EFAULT; + +out_len: + if (put_user(scontext_len, optlen)) + err = -EFAULT; + kfree(scontext); + return err; +} + +static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) +{ + u32 peer_secid = SECSID_NULL; + u16 family; + + if (skb && skb->protocol == htons(ETH_P_IP)) + family = PF_INET; + else if (skb && skb->protocol == htons(ETH_P_IPV6)) + family = PF_INET6; + else if (sock) + family = sock->sk->sk_family; + else + goto out; + + if (sock && family == PF_UNIX) + selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); + else if (skb) + selinux_skb_peerlbl_sid(skb, family, &peer_secid); + +out: + *secid = peer_secid; + if (peer_secid == SECSID_NULL) + return -EINVAL; + return 0; +} + +static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) +{ + struct sk_security_struct *sksec; + + sksec = kzalloc(sizeof(*sksec), priority); + if (!sksec) + return -ENOMEM; + + sksec->peer_sid = SECINITSID_UNLABELED; + sksec->sid = SECINITSID_UNLABELED; + selinux_netlbl_sk_security_reset(sksec); + sk->sk_security = sksec; + + return 0; +} + +static void selinux_sk_free_security(struct sock *sk) +{ + struct sk_security_struct *sksec = sk->sk_security; + + sk->sk_security = NULL; + selinux_netlbl_sk_security_free(sksec); + kfree(sksec); +} + +static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) +{ + struct sk_security_struct *sksec = sk->sk_security; + struct sk_security_struct *newsksec = newsk->sk_security; + + newsksec->sid = sksec->sid; + newsksec->peer_sid = sksec->peer_sid; + newsksec->sclass = sksec->sclass; + + selinux_netlbl_sk_security_reset(newsksec); +} + +static void selinux_sk_getsecid(struct sock *sk, u32 *secid) +{ + if (!sk) + *secid = SECINITSID_ANY_SOCKET; + else { + struct sk_security_struct *sksec = sk->sk_security; + + *secid = sksec->sid; + } +} + +static void selinux_sock_graft(struct sock *sk, struct socket *parent) +{ + struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; + struct sk_security_struct *sksec = sk->sk_security; + + if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || + sk->sk_family == PF_UNIX) + isec->sid = sksec->sid; + sksec->sclass = isec->sclass; +} + +static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, + struct request_sock *req) +{ + struct sk_security_struct *sksec = sk->sk_security; + int err; + u16 family = sk->sk_family; + u32 newsid; + u32 peersid; + + /* handle mapped IPv4 packets arriving via IPv6 sockets */ + if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) + family = PF_INET; + + err = selinux_skb_peerlbl_sid(skb, family, &peersid); + if (err) + return err; + if (peersid == SECSID_NULL) { + req->secid = sksec->sid; + req->peer_secid = SECSID_NULL; + } else { + err = security_sid_mls_copy(sksec->sid, peersid, &newsid); + if (err) + return err; + req->secid = newsid; + req->peer_secid = peersid; + } + + return selinux_netlbl_inet_conn_request(req, family); +} + +static void selinux_inet_csk_clone(struct sock *newsk, + const struct request_sock *req) +{ + struct sk_security_struct *newsksec = newsk->sk_security; + + newsksec->sid = req->secid; + newsksec->peer_sid = req->peer_secid; + /* NOTE: Ideally, we should also get the isec->sid for the + new socket in sync, but we don't have the isec available yet. + So we will wait until sock_graft to do it, by which + time it will have been created and available. */ + + /* We don't need to take any sort of lock here as we are the only + * thread with access to newsksec */ + selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); +} + +static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) +{ + u16 family = sk->sk_family; + struct sk_security_struct *sksec = sk->sk_security; + + /* handle mapped IPv4 packets arriving via IPv6 sockets */ + if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) + family = PF_INET; + + selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); +} + +static int selinux_secmark_relabel_packet(u32 sid) +{ + const struct task_security_struct *__tsec; + u32 tsid; + + __tsec = current_security(); + tsid = __tsec->sid; + + return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); +} + +static void selinux_secmark_refcount_inc(void) +{ + atomic_inc(&selinux_secmark_refcount); +} + +static void selinux_secmark_refcount_dec(void) +{ + atomic_dec(&selinux_secmark_refcount); +} + +static void selinux_req_classify_flow(const struct request_sock *req, + struct flowi *fl) +{ + fl->flowi_secid = req->secid; +} + +static int selinux_tun_dev_create(void) +{ + u32 sid = current_sid(); + + /* we aren't taking into account the "sockcreate" SID since the socket + * that is being created here is not a socket in the traditional sense, + * instead it is a private sock, accessible only to the kernel, and + * representing a wide range of network traffic spanning multiple + * connections unlike traditional sockets - check the TUN driver to + * get a better understanding of why this socket is special */ + + return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, + NULL); +} + +static void selinux_tun_dev_post_create(struct sock *sk) +{ + struct sk_security_struct *sksec = sk->sk_security; + + /* we don't currently perform any NetLabel based labeling here and it + * isn't clear that we would want to do so anyway; while we could apply + * labeling without the support of the TUN user the resulting labeled + * traffic from the other end of the connection would almost certainly + * cause confusion to the TUN user that had no idea network labeling + * protocols were being used */ + + /* see the comments in selinux_tun_dev_create() about why we don't use + * the sockcreate SID here */ + + sksec->sid = current_sid(); + sksec->sclass = SECCLASS_TUN_SOCKET; +} + +static int selinux_tun_dev_attach(struct sock *sk) +{ + struct sk_security_struct *sksec = sk->sk_security; + u32 sid = current_sid(); + int err; + + err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET, + TUN_SOCKET__RELABELFROM, NULL); + if (err) + return err; + err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, + TUN_SOCKET__RELABELTO, NULL); + if (err) + return err; + + sksec->sid = sid; + + return 0; +} + +static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) +{ + int err = 0; + u32 perm; + struct nlmsghdr *nlh; + struct sk_security_struct *sksec = sk->sk_security; + + if (skb->len < NLMSG_SPACE(0)) { + err = -EINVAL; + goto out; + } + nlh = nlmsg_hdr(skb); + + err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); + if (err) { + if (err == -EINVAL) { + audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, + "SELinux: unrecognized netlink message" + " type=%hu for sclass=%hu\n", + nlh->nlmsg_type, sksec->sclass); + if (!selinux_enforcing || security_get_allow_unknown()) + err = 0; + } + + /* Ignore */ + if (err == -ENOENT) + err = 0; + goto out; + } + + err = sock_has_perm(current, sk, perm); +out: + return err; +} + +#ifdef CONFIG_NETFILTER + +static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, + u16 family) +{ + int err; + char *addrp; + u32 peer_sid; + struct common_audit_data ad; + u8 secmark_active; + u8 netlbl_active; + u8 peerlbl_active; + + if (!selinux_policycap_netpeer) + return NF_ACCEPT; + + secmark_active = selinux_secmark_enabled(); + netlbl_active = netlbl_enabled(); + peerlbl_active = netlbl_active || selinux_xfrm_enabled(); + if (!secmark_active && !peerlbl_active) + return NF_ACCEPT; + + if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) + return NF_DROP; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.netif = ifindex; + ad.u.net.family = family; + if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) + return NF_DROP; + + if (peerlbl_active) { + err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, + peer_sid, &ad); + if (err) { + selinux_netlbl_err(skb, err, 1); + return NF_DROP; + } + } + + if (secmark_active) + if (avc_has_perm(peer_sid, skb->secmark, + SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) + return NF_DROP; + + if (netlbl_active) + /* we do this in the FORWARD path and not the POST_ROUTING + * path because we want to make sure we apply the necessary + * labeling before IPsec is applied so we can leverage AH + * protection */ + if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) + return NF_DROP; + + return NF_ACCEPT; +} + +static unsigned int selinux_ipv4_forward(unsigned int hooknum, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + return selinux_ip_forward(skb, in->ifindex, PF_INET); +} + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) +static unsigned int selinux_ipv6_forward(unsigned int hooknum, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + return selinux_ip_forward(skb, in->ifindex, PF_INET6); +} +#endif /* IPV6 */ + +static unsigned int selinux_ip_output(struct sk_buff *skb, + u16 family) +{ + u32 sid; + + if (!netlbl_enabled()) + return NF_ACCEPT; + + /* we do this in the LOCAL_OUT path and not the POST_ROUTING path + * because we want to make sure we apply the necessary labeling + * before IPsec is applied so we can leverage AH protection */ + if (skb->sk) { + struct sk_security_struct *sksec = skb->sk->sk_security; + sid = sksec->sid; + } else + sid = SECINITSID_KERNEL; + if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) + return NF_DROP; + + return NF_ACCEPT; +} + +static unsigned int selinux_ipv4_output(unsigned int hooknum, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + return selinux_ip_output(skb, PF_INET); +} + +static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, + int ifindex, + u16 family) +{ + struct sock *sk = skb->sk; + struct sk_security_struct *sksec; + struct common_audit_data ad; + char *addrp; + u8 proto; + + if (sk == NULL) + return NF_ACCEPT; + sksec = sk->sk_security; + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.netif = ifindex; + ad.u.net.family = family; + if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) + return NF_DROP; + + if (selinux_secmark_enabled()) + if (avc_has_perm(sksec->sid, skb->secmark, + SECCLASS_PACKET, PACKET__SEND, &ad)) + return NF_DROP_ERR(-ECONNREFUSED); + + if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) + return NF_DROP_ERR(-ECONNREFUSED); + + return NF_ACCEPT; +} + +static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, + u16 family) +{ + u32 secmark_perm; + u32 peer_sid; + struct sock *sk; + struct common_audit_data ad; + char *addrp; + u8 secmark_active; + u8 peerlbl_active; + + /* If any sort of compatibility mode is enabled then handoff processing + * to the selinux_ip_postroute_compat() function to deal with the + * special handling. We do this in an attempt to keep this function + * as fast and as clean as possible. */ + if (!selinux_policycap_netpeer) + return selinux_ip_postroute_compat(skb, ifindex, family); +#ifdef CONFIG_XFRM + /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec + * packet transformation so allow the packet to pass without any checks + * since we'll have another chance to perform access control checks + * when the packet is on it's final way out. + * NOTE: there appear to be some IPv6 multicast cases where skb->dst + * is NULL, in this case go ahead and apply access control. */ + if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) + return NF_ACCEPT; +#endif + secmark_active = selinux_secmark_enabled(); + peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); + if (!secmark_active && !peerlbl_active) + return NF_ACCEPT; + + /* if the packet is being forwarded then get the peer label from the + * packet itself; otherwise check to see if it is from a local + * application or the kernel, if from an application get the peer label + * from the sending socket, otherwise use the kernel's sid */ + sk = skb->sk; + if (sk == NULL) { + if (skb->skb_iif) { + secmark_perm = PACKET__FORWARD_OUT; + if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) + return NF_DROP; + } else { + secmark_perm = PACKET__SEND; + peer_sid = SECINITSID_KERNEL; + } + } else { + struct sk_security_struct *sksec = sk->sk_security; + peer_sid = sksec->sid; + secmark_perm = PACKET__SEND; + } + + COMMON_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.netif = ifindex; + ad.u.net.family = family; + if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) + return NF_DROP; + + if (secmark_active) + if (avc_has_perm(peer_sid, skb->secmark, + SECCLASS_PACKET, secmark_perm, &ad)) + return NF_DROP_ERR(-ECONNREFUSED); + + if (peerlbl_active) { + u32 if_sid; + u32 node_sid; + + if (sel_netif_sid(ifindex, &if_sid)) + return NF_DROP; + if (avc_has_perm(peer_sid, if_sid, + SECCLASS_NETIF, NETIF__EGRESS, &ad)) + return NF_DROP_ERR(-ECONNREFUSED); + + if (sel_netnode_sid(addrp, family, &node_sid)) + return NF_DROP; + if (avc_has_perm(peer_sid, node_sid, + SECCLASS_NODE, NODE__SENDTO, &ad)) + return NF_DROP_ERR(-ECONNREFUSED); + } + + return NF_ACCEPT; +} + +static unsigned int selinux_ipv4_postroute(unsigned int hooknum, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + return selinux_ip_postroute(skb, out->ifindex, PF_INET); +} + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) +static unsigned int selinux_ipv6_postroute(unsigned int hooknum, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + return selinux_ip_postroute(skb, out->ifindex, PF_INET6); +} +#endif /* IPV6 */ + +#endif /* CONFIG_NETFILTER */ + +static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) +{ + int err; + + err = cap_netlink_send(sk, skb); + if (err) + return err; + + return selinux_nlmsg_perm(sk, skb); +} + +static int selinux_netlink_recv(struct sk_buff *skb, int capability) +{ + int err; + struct common_audit_data ad; + u32 sid; + + err = cap_netlink_recv(skb, capability); + if (err) + return err; + + COMMON_AUDIT_DATA_INIT(&ad, CAP); + ad.u.cap = capability; + + security_task_getsecid(current, &sid); + return avc_has_perm(sid, sid, SECCLASS_CAPABILITY, + CAP_TO_MASK(capability), &ad); +} + +static int ipc_alloc_security(struct task_struct *task, + struct kern_ipc_perm *perm, + u16 sclass) +{ + struct ipc_security_struct *isec; + u32 sid; + + isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); + if (!isec) + return -ENOMEM; + + sid = task_sid(task); + isec->sclass = sclass; + isec->sid = sid; + perm->security = isec; + + return 0; +} + +static void ipc_free_security(struct kern_ipc_perm *perm) +{ + struct ipc_security_struct *isec = perm->security; + perm->security = NULL; + kfree(isec); +} + +static int msg_msg_alloc_security(struct msg_msg *msg) +{ + struct msg_security_struct *msec; + + msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); + if (!msec) + return -ENOMEM; + + msec->sid = SECINITSID_UNLABELED; + msg->security = msec; + + return 0; +} + +static void msg_msg_free_security(struct msg_msg *msg) +{ + struct msg_security_struct *msec = msg->security; + + msg->security = NULL; + kfree(msec); +} + +static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, + u32 perms) +{ + struct ipc_security_struct *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + + isec = ipc_perms->security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = ipc_perms->key; + + return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); +} + +static int selinux_msg_msg_alloc_security(struct msg_msg *msg) +{ + return msg_msg_alloc_security(msg); +} + +static void selinux_msg_msg_free_security(struct msg_msg *msg) +{ + msg_msg_free_security(msg); +} + +/* message queue security operations */ +static int selinux_msg_queue_alloc_security(struct msg_queue *msq) +{ + struct ipc_security_struct *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + int rc; + + rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); + if (rc) + return rc; + + isec = msq->q_perm.security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = msq->q_perm.key; + + rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, + MSGQ__CREATE, &ad); + if (rc) { + ipc_free_security(&msq->q_perm); + return rc; + } + return 0; +} + +static void selinux_msg_queue_free_security(struct msg_queue *msq) +{ + ipc_free_security(&msq->q_perm); +} + +static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) +{ + struct ipc_security_struct *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + + isec = msq->q_perm.security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = msq->q_perm.key; + + return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, + MSGQ__ASSOCIATE, &ad); +} + +static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) +{ + int err; + int perms; + + switch (cmd) { + case IPC_INFO: + case MSG_INFO: + /* No specific object, just general system-wide information. */ + return task_has_system(current, SYSTEM__IPC_INFO); + case IPC_STAT: + case MSG_STAT: + perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; + break; + case IPC_SET: + perms = MSGQ__SETATTR; + break; + case IPC_RMID: + perms = MSGQ__DESTROY; + break; + default: + return 0; + } + + err = ipc_has_perm(&msq->q_perm, perms); + return err; +} + +static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) +{ + struct ipc_security_struct *isec; + struct msg_security_struct *msec; + struct common_audit_data ad; + u32 sid = current_sid(); + int rc; + + isec = msq->q_perm.security; + msec = msg->security; + + /* + * First time through, need to assign label to the message + */ + if (msec->sid == SECINITSID_UNLABELED) { + /* + * Compute new sid based on current process and + * message queue this message will be stored in + */ + rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, + NULL, &msec->sid); + if (rc) + return rc; + } + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = msq->q_perm.key; + + /* Can this process write to the queue? */ + rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, + MSGQ__WRITE, &ad); + if (!rc) + /* Can this process send the message */ + rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, + MSG__SEND, &ad); + if (!rc) + /* Can the message be put in the queue? */ + rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, + MSGQ__ENQUEUE, &ad); + + return rc; +} + +static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, + struct task_struct *target, + long type, int mode) +{ + struct ipc_security_struct *isec; + struct msg_security_struct *msec; + struct common_audit_data ad; + u32 sid = task_sid(target); + int rc; + + isec = msq->q_perm.security; + msec = msg->security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = msq->q_perm.key; + + rc = avc_has_perm(sid, isec->sid, + SECCLASS_MSGQ, MSGQ__READ, &ad); + if (!rc) + rc = avc_has_perm(sid, msec->sid, + SECCLASS_MSG, MSG__RECEIVE, &ad); + return rc; +} + +/* Shared Memory security operations */ +static int selinux_shm_alloc_security(struct shmid_kernel *shp) +{ + struct ipc_security_struct *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + int rc; + + rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); + if (rc) + return rc; + + isec = shp->shm_perm.security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = shp->shm_perm.key; + + rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, + SHM__CREATE, &ad); + if (rc) { + ipc_free_security(&shp->shm_perm); + return rc; + } + return 0; +} + +static void selinux_shm_free_security(struct shmid_kernel *shp) +{ + ipc_free_security(&shp->shm_perm); +} + +static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) +{ + struct ipc_security_struct *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + + isec = shp->shm_perm.security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = shp->shm_perm.key; + + return avc_has_perm(sid, isec->sid, SECCLASS_SHM, + SHM__ASSOCIATE, &ad); +} + +/* Note, at this point, shp is locked down */ +static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) +{ + int perms; + int err; + + switch (cmd) { + case IPC_INFO: + case SHM_INFO: + /* No specific object, just general system-wide information. */ + return task_has_system(current, SYSTEM__IPC_INFO); + case IPC_STAT: + case SHM_STAT: + perms = SHM__GETATTR | SHM__ASSOCIATE; + break; + case IPC_SET: + perms = SHM__SETATTR; + break; + case SHM_LOCK: + case SHM_UNLOCK: + perms = SHM__LOCK; + break; + case IPC_RMID: + perms = SHM__DESTROY; + break; + default: + return 0; + } + + err = ipc_has_perm(&shp->shm_perm, perms); + return err; +} + +static int selinux_shm_shmat(struct shmid_kernel *shp, + char __user *shmaddr, int shmflg) +{ + u32 perms; + + if (shmflg & SHM_RDONLY) + perms = SHM__READ; + else + perms = SHM__READ | SHM__WRITE; + + return ipc_has_perm(&shp->shm_perm, perms); +} + +/* Semaphore security operations */ +static int selinux_sem_alloc_security(struct sem_array *sma) +{ + struct ipc_security_struct *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + int rc; + + rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); + if (rc) + return rc; + + isec = sma->sem_perm.security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = sma->sem_perm.key; + + rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, + SEM__CREATE, &ad); + if (rc) { + ipc_free_security(&sma->sem_perm); + return rc; + } + return 0; +} + +static void selinux_sem_free_security(struct sem_array *sma) +{ + ipc_free_security(&sma->sem_perm); +} + +static int selinux_sem_associate(struct sem_array *sma, int semflg) +{ + struct ipc_security_struct *isec; + struct common_audit_data ad; + u32 sid = current_sid(); + + isec = sma->sem_perm.security; + + COMMON_AUDIT_DATA_INIT(&ad, IPC); + ad.u.ipc_id = sma->sem_perm.key; + + return avc_has_perm(sid, isec->sid, SECCLASS_SEM, + SEM__ASSOCIATE, &ad); +} + +/* Note, at this point, sma is locked down */ +static int selinux_sem_semctl(struct sem_array *sma, int cmd) +{ + int err; + u32 perms; + + switch (cmd) { + case IPC_INFO: + case SEM_INFO: + /* No specific object, just general system-wide information. */ + return task_has_system(current, SYSTEM__IPC_INFO); + case GETPID: + case GETNCNT: + case GETZCNT: + perms = SEM__GETATTR; + break; + case GETVAL: + case GETALL: + perms = SEM__READ; + break; + case SETVAL: + case SETALL: + perms = SEM__WRITE; + break; + case IPC_RMID: + perms = SEM__DESTROY; + break; + case IPC_SET: + perms = SEM__SETATTR; + break; + case IPC_STAT: + case SEM_STAT: + perms = SEM__GETATTR | SEM__ASSOCIATE; + break; + default: + return 0; + } + + err = ipc_has_perm(&sma->sem_perm, perms); + return err; +} + +static int selinux_sem_semop(struct sem_array *sma, + struct sembuf *sops, unsigned nsops, int alter) +{ + u32 perms; + + if (alter) + perms = SEM__READ | SEM__WRITE; + else + perms = SEM__READ; + + return ipc_has_perm(&sma->sem_perm, perms); +} + +static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) +{ + u32 av = 0; + + av = 0; + if (flag & S_IRUGO) + av |= IPC__UNIX_READ; + if (flag & S_IWUGO) + av |= IPC__UNIX_WRITE; + + if (av == 0) + return 0; + + return ipc_has_perm(ipcp, av); +} + +static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) +{ + struct ipc_security_struct *isec = ipcp->security; + *secid = isec->sid; +} + +static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) +{ + if (inode) + inode_doinit_with_dentry(inode, dentry); +} + +static int selinux_getprocattr(struct task_struct *p, + char *name, char **value) +{ + const struct task_security_struct *__tsec; + u32 sid; + int error; + unsigned len; + + if (current != p) { + error = current_has_perm(p, PROCESS__GETATTR); + if (error) + return error; + } + + rcu_read_lock(); + __tsec = __task_cred(p)->security; + + if (!strcmp(name, "current")) + sid = __tsec->sid; + else if (!strcmp(name, "prev")) + sid = __tsec->osid; + else if (!strcmp(name, "exec")) + sid = __tsec->exec_sid; + else if (!strcmp(name, "fscreate")) + sid = __tsec->create_sid; + else if (!strcmp(name, "keycreate")) + sid = __tsec->keycreate_sid; + else if (!strcmp(name, "sockcreate")) + sid = __tsec->sockcreate_sid; + else + goto invalid; + rcu_read_unlock(); + + if (!sid) + return 0; + + error = security_sid_to_context(sid, value, &len); + if (error) + return error; + return len; + +invalid: + rcu_read_unlock(); + return -EINVAL; +} + +static int selinux_setprocattr(struct task_struct *p, + char *name, void *value, size_t size) +{ + struct task_security_struct *tsec; + struct task_struct *tracer; + struct cred *new; + u32 sid = 0, ptsid; + int error; + char *str = value; + + if (current != p) { + /* SELinux only allows a process to change its own + security attributes. */ + return -EACCES; + } + + /* + * Basic control over ability to set these attributes at all. + * current == p, but we'll pass them separately in case the + * above restriction is ever removed. + */ + if (!strcmp(name, "exec")) + error = current_has_perm(p, PROCESS__SETEXEC); + else if (!strcmp(name, "fscreate")) + error = current_has_perm(p, PROCESS__SETFSCREATE); + else if (!strcmp(name, "keycreate")) + error = current_has_perm(p, PROCESS__SETKEYCREATE); + else if (!strcmp(name, "sockcreate")) + error = current_has_perm(p, PROCESS__SETSOCKCREATE); + else if (!strcmp(name, "current")) + error = current_has_perm(p, PROCESS__SETCURRENT); + else + error = -EINVAL; + if (error) + return error; + + /* Obtain a SID for the context, if one was specified. */ + if (size && str[1] && str[1] != '\n') { + if (str[size-1] == '\n') { + str[size-1] = 0; + size--; + } + error = security_context_to_sid(value, size, &sid); + if (error == -EINVAL && !strcmp(name, "fscreate")) { + if (!capable(CAP_MAC_ADMIN)) + return error; + error = security_context_to_sid_force(value, size, + &sid); + } + if (error) + return error; + } + + new = prepare_creds(); + if (!new) + return -ENOMEM; + + /* Permission checking based on the specified context is + performed during the actual operation (execve, + open/mkdir/...), when we know the full context of the + operation. See selinux_bprm_set_creds for the execve + checks and may_create for the file creation checks. The + operation will then fail if the context is not permitted. */ + tsec = new->security; + if (!strcmp(name, "exec")) { + tsec->exec_sid = sid; + } else if (!strcmp(name, "fscreate")) { + tsec->create_sid = sid; + } else if (!strcmp(name, "keycreate")) { + error = may_create_key(sid, p); + if (error) + goto abort_change; + tsec->keycreate_sid = sid; + } else if (!strcmp(name, "sockcreate")) { + tsec->sockcreate_sid = sid; + } else if (!strcmp(name, "current")) { + error = -EINVAL; + if (sid == 0) + goto abort_change; + + /* Only allow single threaded processes to change context */ + error = -EPERM; + if (!current_is_single_threaded()) { + error = security_bounded_transition(tsec->sid, sid); + if (error) + goto abort_change; + } + + /* Check permissions for the transition. */ + error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, + PROCESS__DYNTRANSITION, NULL); + if (error) + goto abort_change; + + /* Check for ptracing, and update the task SID if ok. + Otherwise, leave SID unchanged and fail. */ + ptsid = 0; + task_lock(p); + tracer = tracehook_tracer_task(p); + if (tracer) + ptsid = task_sid(tracer); + task_unlock(p); + + if (tracer) { + error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, + PROCESS__PTRACE, NULL); + if (error) + goto abort_change; + } + + tsec->sid = sid; + } else { + error = -EINVAL; + goto abort_change; + } + + commit_creds(new); + return size; + +abort_change: + abort_creds(new); + return error; +} + +static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) +{ + return security_sid_to_context(secid, secdata, seclen); +} + +static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) +{ + return security_context_to_sid(secdata, seclen, secid); +} + +static void selinux_release_secctx(char *secdata, u32 seclen) +{ + kfree(secdata); +} + +/* + * called with inode->i_mutex locked + */ +static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) +{ + return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); +} + +/* + * called with inode->i_mutex locked + */ +static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) +{ + return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); +} + +static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) +{ + int len = 0; + len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, + ctx, true); + if (len < 0) + return len; + *ctxlen = len; + return 0; +} +#ifdef CONFIG_KEYS + +static int selinux_key_alloc(struct key *k, const struct cred *cred, + unsigned long flags) +{ + const struct task_security_struct *tsec; + struct key_security_struct *ksec; + + ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); + if (!ksec) + return -ENOMEM; + + tsec = cred->security; + if (tsec->keycreate_sid) + ksec->sid = tsec->keycreate_sid; + else + ksec->sid = tsec->sid; + + k->security = ksec; + return 0; +} + +static void selinux_key_free(struct key *k) +{ + struct key_security_struct *ksec = k->security; + + k->security = NULL; + kfree(ksec); +} + +static int selinux_key_permission(key_ref_t key_ref, + const struct cred *cred, + key_perm_t perm) +{ + struct key *key; + struct key_security_struct *ksec; + u32 sid; + + /* if no specific permissions are requested, we skip the + permission check. No serious, additional covert channels + appear to be created. */ + if (perm == 0) + return 0; + + sid = cred_sid(cred); + + key = key_ref_to_ptr(key_ref); + ksec = key->security; + + return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); +} + +static int selinux_key_getsecurity(struct key *key, char **_buffer) +{ + struct key_security_struct *ksec = key->security; + char *context = NULL; + unsigned len; + int rc; + + rc = security_sid_to_context(ksec->sid, &context, &len); + if (!rc) + rc = len; + *_buffer = context; + return rc; +} + +#endif + +static struct security_operations selinux_ops = { + .name = "selinux", + + .ptrace_access_check = selinux_ptrace_access_check, + .ptrace_traceme = selinux_ptrace_traceme, + .capget = selinux_capget, + .capset = selinux_capset, + .capable = selinux_capable, + .quotactl = selinux_quotactl, + .quota_on = selinux_quota_on, + .syslog = selinux_syslog, + .vm_enough_memory = selinux_vm_enough_memory, + + .netlink_send = selinux_netlink_send, + .netlink_recv = selinux_netlink_recv, + + .bprm_set_creds = selinux_bprm_set_creds, + .bprm_committing_creds = selinux_bprm_committing_creds, + .bprm_committed_creds = selinux_bprm_committed_creds, + .bprm_secureexec = selinux_bprm_secureexec, + + .sb_alloc_security = selinux_sb_alloc_security, + .sb_free_security = selinux_sb_free_security, + .sb_copy_data = selinux_sb_copy_data, + .sb_remount = selinux_sb_remount, + .sb_kern_mount = selinux_sb_kern_mount, + .sb_show_options = selinux_sb_show_options, + .sb_statfs = selinux_sb_statfs, + .sb_mount = selinux_mount, + .sb_umount = selinux_umount, + .sb_set_mnt_opts = selinux_set_mnt_opts, + .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, + .sb_parse_opts_str = selinux_parse_opts_str, + + + .inode_alloc_security = selinux_inode_alloc_security, + .inode_free_security = selinux_inode_free_security, + .inode_init_security = selinux_inode_init_security, + .inode_create = selinux_inode_create, + .inode_link = selinux_inode_link, + .inode_unlink = selinux_inode_unlink, + .inode_symlink = selinux_inode_symlink, + .inode_mkdir = selinux_inode_mkdir, + .inode_rmdir = selinux_inode_rmdir, + .inode_mknod = selinux_inode_mknod, + .inode_rename = selinux_inode_rename, + .inode_readlink = selinux_inode_readlink, + .inode_follow_link = selinux_inode_follow_link, + .inode_permission = selinux_inode_permission, + .inode_setattr = selinux_inode_setattr, + .inode_getattr = selinux_inode_getattr, + .inode_setxattr = selinux_inode_setxattr, + .inode_post_setxattr = selinux_inode_post_setxattr, + .inode_getxattr = selinux_inode_getxattr, + .inode_listxattr = selinux_inode_listxattr, + .inode_removexattr = selinux_inode_removexattr, + .inode_getsecurity = selinux_inode_getsecurity, + .inode_setsecurity = selinux_inode_setsecurity, + .inode_listsecurity = selinux_inode_listsecurity, + .inode_getsecid = selinux_inode_getsecid, + + .file_permission = selinux_file_permission, + .file_alloc_security = selinux_file_alloc_security, + .file_free_security = selinux_file_free_security, + .file_ioctl = selinux_file_ioctl, + .file_mmap = selinux_file_mmap, + .file_mprotect = selinux_file_mprotect, + .file_lock = selinux_file_lock, + .file_fcntl = selinux_file_fcntl, + .file_set_fowner = selinux_file_set_fowner, + .file_send_sigiotask = selinux_file_send_sigiotask, + .file_receive = selinux_file_receive, + + .dentry_open = selinux_dentry_open, + + .task_create = selinux_task_create, + .cred_alloc_blank = selinux_cred_alloc_blank, + .cred_free = selinux_cred_free, + .cred_prepare = selinux_cred_prepare, + .cred_transfer = selinux_cred_transfer, + .kernel_act_as = selinux_kernel_act_as, + .kernel_create_files_as = selinux_kernel_create_files_as, + .kernel_module_request = selinux_kernel_module_request, + .task_setpgid = selinux_task_setpgid, + .task_getpgid = selinux_task_getpgid, + .task_getsid = selinux_task_getsid, + .task_getsecid = selinux_task_getsecid, + .task_setnice = selinux_task_setnice, + .task_setioprio = selinux_task_setioprio, + .task_getioprio = selinux_task_getioprio, + .task_setrlimit = selinux_task_setrlimit, + .task_setscheduler = selinux_task_setscheduler, + .task_getscheduler = selinux_task_getscheduler, + .task_movememory = selinux_task_movememory, + .task_kill = selinux_task_kill, + .task_wait = selinux_task_wait, + .task_to_inode = selinux_task_to_inode, + + .ipc_permission = selinux_ipc_permission, + .ipc_getsecid = selinux_ipc_getsecid, + + .msg_msg_alloc_security = selinux_msg_msg_alloc_security, + .msg_msg_free_security = selinux_msg_msg_free_security, + + .msg_queue_alloc_security = selinux_msg_queue_alloc_security, + .msg_queue_free_security = selinux_msg_queue_free_security, + .msg_queue_associate = selinux_msg_queue_associate, + .msg_queue_msgctl = selinux_msg_queue_msgctl, + .msg_queue_msgsnd = selinux_msg_queue_msgsnd, + .msg_queue_msgrcv = selinux_msg_queue_msgrcv, + + .shm_alloc_security = selinux_shm_alloc_security, + .shm_free_security = selinux_shm_free_security, + .shm_associate = selinux_shm_associate, + .shm_shmctl = selinux_shm_shmctl, + .shm_shmat = selinux_shm_shmat, + + .sem_alloc_security = selinux_sem_alloc_security, + .sem_free_security = selinux_sem_free_security, + .sem_associate = selinux_sem_associate, + .sem_semctl = selinux_sem_semctl, + .sem_semop = selinux_sem_semop, + + .d_instantiate = selinux_d_instantiate, + + .getprocattr = selinux_getprocattr, + .setprocattr = selinux_setprocattr, + + .secid_to_secctx = selinux_secid_to_secctx, + .secctx_to_secid = selinux_secctx_to_secid, + .release_secctx = selinux_release_secctx, + .inode_notifysecctx = selinux_inode_notifysecctx, + .inode_setsecctx = selinux_inode_setsecctx, + .inode_getsecctx = selinux_inode_getsecctx, + + .unix_stream_connect = selinux_socket_unix_stream_connect, + .unix_may_send = selinux_socket_unix_may_send, + + .socket_create = selinux_socket_create, + .socket_post_create = selinux_socket_post_create, + .socket_bind = selinux_socket_bind, + .socket_connect = selinux_socket_connect, + .socket_listen = selinux_socket_listen, + .socket_accept = selinux_socket_accept, + .socket_sendmsg = selinux_socket_sendmsg, + .socket_recvmsg = selinux_socket_recvmsg, + .socket_getsockname = selinux_socket_getsockname, + .socket_getpeername = selinux_socket_getpeername, + .socket_getsockopt = selinux_socket_getsockopt, + .socket_setsockopt = selinux_socket_setsockopt, + .socket_shutdown = selinux_socket_shutdown, + .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, + .socket_getpeersec_stream = selinux_socket_getpeersec_stream, + .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, + .sk_alloc_security = selinux_sk_alloc_security, + .sk_free_security = selinux_sk_free_security, + .sk_clone_security = selinux_sk_clone_security, + .sk_getsecid = selinux_sk_getsecid, + .sock_graft = selinux_sock_graft, + .inet_conn_request = selinux_inet_conn_request, + .inet_csk_clone = selinux_inet_csk_clone, + .inet_conn_established = selinux_inet_conn_established, + .secmark_relabel_packet = selinux_secmark_relabel_packet, + .secmark_refcount_inc = selinux_secmark_refcount_inc, + .secmark_refcount_dec = selinux_secmark_refcount_dec, + .req_classify_flow = selinux_req_classify_flow, + .tun_dev_create = selinux_tun_dev_create, + .tun_dev_post_create = selinux_tun_dev_post_create, + .tun_dev_attach = selinux_tun_dev_attach, + +#ifdef CONFIG_SECURITY_NETWORK_XFRM + .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, + .xfrm_policy_clone_security = selinux_xfrm_policy_clone, + .xfrm_policy_free_security = selinux_xfrm_policy_free, + .xfrm_policy_delete_security = selinux_xfrm_policy_delete, + .xfrm_state_alloc_security = selinux_xfrm_state_alloc, + .xfrm_state_free_security = selinux_xfrm_state_free, + .xfrm_state_delete_security = selinux_xfrm_state_delete, + .xfrm_policy_lookup = selinux_xfrm_policy_lookup, + .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, + .xfrm_decode_session = selinux_xfrm_decode_session, +#endif + +#ifdef CONFIG_KEYS + .key_alloc = selinux_key_alloc, + .key_free = selinux_key_free, + .key_permission = selinux_key_permission, + .key_getsecurity = selinux_key_getsecurity, +#endif + +#ifdef CONFIG_AUDIT + .audit_rule_init = selinux_audit_rule_init, + .audit_rule_known = selinux_audit_rule_known, + .audit_rule_match = selinux_audit_rule_match, + .audit_rule_free = selinux_audit_rule_free, +#endif +}; + +static __init int selinux_init(void) +{ + if (!security_module_enable(&selinux_ops)) { + selinux_enabled = 0; + return 0; + } + + if (!selinux_enabled) { + printk(KERN_INFO "SELinux: Disabled at boot.\n"); + return 0; + } + + printk(KERN_INFO "SELinux: Initializing.\n"); + + /* Set the security state for the initial task. */ + cred_init_security(); + + default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); + + sel_inode_cache = kmem_cache_create("selinux_inode_security", + sizeof(struct inode_security_struct), + 0, SLAB_PANIC, NULL); + avc_init(); + + if (register_security(&selinux_ops)) + panic("SELinux: Unable to register with kernel.\n"); + + if (selinux_enforcing) + printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); + else + printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); + + return 0; +} + +static void delayed_superblock_init(struct super_block *sb, void *unused) +{ + superblock_doinit(sb, NULL); +} + +void selinux_complete_init(void) +{ + printk(KERN_DEBUG "SELinux: Completing initialization.\n"); + + /* Set up any superblocks initialized prior to the policy load. */ + printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); + iterate_supers(delayed_superblock_init, NULL); +} + +/* SELinux requires early initialization in order to label + all processes and objects when they are created. */ +security_initcall(selinux_init); + +#if defined(CONFIG_NETFILTER) + +static struct nf_hook_ops selinux_ipv4_ops[] = { + { + .hook = selinux_ipv4_postroute, + .owner = THIS_MODULE, + .pf = PF_INET, + .hooknum = NF_INET_POST_ROUTING, + .priority = NF_IP_PRI_SELINUX_LAST, + }, + { + .hook = selinux_ipv4_forward, + .owner = THIS_MODULE, + .pf = PF_INET, + .hooknum = NF_INET_FORWARD, + .priority = NF_IP_PRI_SELINUX_FIRST, + }, + { + .hook = selinux_ipv4_output, + .owner = THIS_MODULE, + .pf = PF_INET, + .hooknum = NF_INET_LOCAL_OUT, + .priority = NF_IP_PRI_SELINUX_FIRST, + } +}; + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) + +static struct nf_hook_ops selinux_ipv6_ops[] = { + { + .hook = selinux_ipv6_postroute, + .owner = THIS_MODULE, + .pf = PF_INET6, + .hooknum = NF_INET_POST_ROUTING, + .priority = NF_IP6_PRI_SELINUX_LAST, + }, + { + .hook = selinux_ipv6_forward, + .owner = THIS_MODULE, + .pf = PF_INET6, + .hooknum = NF_INET_FORWARD, + .priority = NF_IP6_PRI_SELINUX_FIRST, + } +}; + +#endif /* IPV6 */ + +static int __init selinux_nf_ip_init(void) +{ + int err = 0; + + if (!selinux_enabled) + goto out; + + printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); + + err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); + if (err) + panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); + +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) + err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); + if (err) + panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); +#endif /* IPV6 */ + +out: + return err; +} + +__initcall(selinux_nf_ip_init); + +#ifdef CONFIG_SECURITY_SELINUX_DISABLE +static void selinux_nf_ip_exit(void) +{ + printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); + + nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) + nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); +#endif /* IPV6 */ +} +#endif + +#else /* CONFIG_NETFILTER */ + +#ifdef CONFIG_SECURITY_SELINUX_DISABLE +#define selinux_nf_ip_exit() +#endif + +#endif /* CONFIG_NETFILTER */ + +#ifdef CONFIG_SECURITY_SELINUX_DISABLE +static int selinux_disabled; + +int selinux_disable(void) +{ + extern void exit_sel_fs(void); + + if (ss_initialized) { + /* Not permitted after initial policy load. */ + return -EINVAL; + } + + if (selinux_disabled) { + /* Only do this once. */ + return -EINVAL; + } + + printk(KERN_INFO "SELinux: Disabled at runtime.\n"); + + selinux_disabled = 1; + selinux_enabled = 0; + + reset_security_ops(); + + /* Try to destroy the avc node cache */ + avc_disable(); + + /* Unregister netfilter hooks. */ + selinux_nf_ip_exit(); + + /* Unregister selinuxfs. */ + exit_sel_fs(); + + return 0; +} +#endif |