diff options
Diffstat (limited to 'security/tomoyo/tomoyo.c')
-rw-r--r-- | security/tomoyo/tomoyo.c | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c new file mode 100644 index 00000000..95d3f957 --- /dev/null +++ b/security/tomoyo/tomoyo.c @@ -0,0 +1,289 @@ +/* + * security/tomoyo/tomoyo.c + * + * LSM hooks for TOMOYO Linux. + * + * Copyright (C) 2005-2010 NTT DATA CORPORATION + */ + +#include <linux/security.h> +#include "common.h" + +static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp) +{ + new->security = NULL; + return 0; +} + +static int tomoyo_cred_prepare(struct cred *new, const struct cred *old, + gfp_t gfp) +{ + struct tomoyo_domain_info *domain = old->security; + new->security = domain; + if (domain) + atomic_inc(&domain->users); + return 0; +} + +static void tomoyo_cred_transfer(struct cred *new, const struct cred *old) +{ + tomoyo_cred_prepare(new, old, 0); +} + +static void tomoyo_cred_free(struct cred *cred) +{ + struct tomoyo_domain_info *domain = cred->security; + if (domain) + atomic_dec(&domain->users); +} + +static int tomoyo_bprm_set_creds(struct linux_binprm *bprm) +{ + int rc; + + rc = cap_bprm_set_creds(bprm); + if (rc) + return rc; + + /* + * Do only if this function is called for the first time of an execve + * operation. + */ + if (bprm->cred_prepared) + return 0; + /* + * Load policy if /sbin/tomoyo-init exists and /sbin/init is requested + * for the first time. + */ + if (!tomoyo_policy_loaded) + tomoyo_load_policy(bprm->filename); + /* + * Release reference to "struct tomoyo_domain_info" stored inside + * "bprm->cred->security". New reference to "struct tomoyo_domain_info" + * stored inside "bprm->cred->security" will be acquired later inside + * tomoyo_find_next_domain(). + */ + atomic_dec(&((struct tomoyo_domain_info *) + bprm->cred->security)->users); + /* + * Tell tomoyo_bprm_check_security() is called for the first time of an + * execve operation. + */ + bprm->cred->security = NULL; + return 0; +} + +static int tomoyo_bprm_check_security(struct linux_binprm *bprm) +{ + struct tomoyo_domain_info *domain = bprm->cred->security; + + /* + * Execute permission is checked against pathname passed to do_execve() + * using current domain. + */ + if (!domain) { + const int idx = tomoyo_read_lock(); + const int err = tomoyo_find_next_domain(bprm); + tomoyo_read_unlock(idx); + return err; + } + /* + * Read permission is checked against interpreters using next domain. + */ + return tomoyo_check_open_permission(domain, &bprm->file->f_path, O_RDONLY); +} + +static int tomoyo_path_truncate(struct path *path) +{ + return tomoyo_path_perm(TOMOYO_TYPE_TRUNCATE, path); +} + +static int tomoyo_path_unlink(struct path *parent, struct dentry *dentry) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_path_perm(TOMOYO_TYPE_UNLINK, &path); +} + +static int tomoyo_path_mkdir(struct path *parent, struct dentry *dentry, + int mode) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_path_number_perm(TOMOYO_TYPE_MKDIR, &path, + mode & S_IALLUGO); +} + +static int tomoyo_path_rmdir(struct path *parent, struct dentry *dentry) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_path_perm(TOMOYO_TYPE_RMDIR, &path); +} + +static int tomoyo_path_symlink(struct path *parent, struct dentry *dentry, + const char *old_name) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_path_perm(TOMOYO_TYPE_SYMLINK, &path); +} + +static int tomoyo_path_mknod(struct path *parent, struct dentry *dentry, + int mode, unsigned int dev) +{ + struct path path = { parent->mnt, dentry }; + int type = TOMOYO_TYPE_CREATE; + const unsigned int perm = mode & S_IALLUGO; + + switch (mode & S_IFMT) { + case S_IFCHR: + type = TOMOYO_TYPE_MKCHAR; + break; + case S_IFBLK: + type = TOMOYO_TYPE_MKBLOCK; + break; + default: + goto no_dev; + } + return tomoyo_mkdev_perm(type, &path, perm, dev); + no_dev: + switch (mode & S_IFMT) { + case S_IFIFO: + type = TOMOYO_TYPE_MKFIFO; + break; + case S_IFSOCK: + type = TOMOYO_TYPE_MKSOCK; + break; + } + return tomoyo_path_number_perm(type, &path, perm); +} + +static int tomoyo_path_link(struct dentry *old_dentry, struct path *new_dir, + struct dentry *new_dentry) +{ + struct path path1 = { new_dir->mnt, old_dentry }; + struct path path2 = { new_dir->mnt, new_dentry }; + return tomoyo_path2_perm(TOMOYO_TYPE_LINK, &path1, &path2); +} + +static int tomoyo_path_rename(struct path *old_parent, + struct dentry *old_dentry, + struct path *new_parent, + struct dentry *new_dentry) +{ + struct path path1 = { old_parent->mnt, old_dentry }; + struct path path2 = { new_parent->mnt, new_dentry }; + return tomoyo_path2_perm(TOMOYO_TYPE_RENAME, &path1, &path2); +} + +static int tomoyo_file_fcntl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + if (cmd == F_SETFL && ((arg ^ file->f_flags) & O_APPEND)) + return tomoyo_path_perm(TOMOYO_TYPE_REWRITE, &file->f_path); + return 0; +} + +static int tomoyo_dentry_open(struct file *f, const struct cred *cred) +{ + int flags = f->f_flags; + /* Don't check read permission here if called from do_execve(). */ + if (current->in_execve) + return 0; + return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags); +} + +static int tomoyo_file_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + return tomoyo_path_number_perm(TOMOYO_TYPE_IOCTL, &file->f_path, cmd); +} + +static int tomoyo_path_chmod(struct dentry *dentry, struct vfsmount *mnt, + mode_t mode) +{ + struct path path = { mnt, dentry }; + return tomoyo_path_number_perm(TOMOYO_TYPE_CHMOD, &path, + mode & S_IALLUGO); +} + +static int tomoyo_path_chown(struct path *path, uid_t uid, gid_t gid) +{ + int error = 0; + if (uid != (uid_t) -1) + error = tomoyo_path_number_perm(TOMOYO_TYPE_CHOWN, path, uid); + if (!error && gid != (gid_t) -1) + error = tomoyo_path_number_perm(TOMOYO_TYPE_CHGRP, path, gid); + return error; +} + +static int tomoyo_path_chroot(struct path *path) +{ + return tomoyo_path_perm(TOMOYO_TYPE_CHROOT, path); +} + +static int tomoyo_sb_mount(char *dev_name, struct path *path, + char *type, unsigned long flags, void *data) +{ + return tomoyo_mount_permission(dev_name, path, type, flags, data); +} + +static int tomoyo_sb_umount(struct vfsmount *mnt, int flags) +{ + struct path path = { mnt, mnt->mnt_root }; + return tomoyo_path_perm(TOMOYO_TYPE_UMOUNT, &path); +} + +static int tomoyo_sb_pivotroot(struct path *old_path, struct path *new_path) +{ + return tomoyo_path2_perm(TOMOYO_TYPE_PIVOT_ROOT, new_path, old_path); +} + +/* + * tomoyo_security_ops is a "struct security_operations" which is used for + * registering TOMOYO. + */ +static struct security_operations tomoyo_security_ops = { + .name = "tomoyo", + .cred_alloc_blank = tomoyo_cred_alloc_blank, + .cred_prepare = tomoyo_cred_prepare, + .cred_transfer = tomoyo_cred_transfer, + .cred_free = tomoyo_cred_free, + .bprm_set_creds = tomoyo_bprm_set_creds, + .bprm_check_security = tomoyo_bprm_check_security, + .file_fcntl = tomoyo_file_fcntl, + .dentry_open = tomoyo_dentry_open, + .path_truncate = tomoyo_path_truncate, + .path_unlink = tomoyo_path_unlink, + .path_mkdir = tomoyo_path_mkdir, + .path_rmdir = tomoyo_path_rmdir, + .path_symlink = tomoyo_path_symlink, + .path_mknod = tomoyo_path_mknod, + .path_link = tomoyo_path_link, + .path_rename = tomoyo_path_rename, + .file_ioctl = tomoyo_file_ioctl, + .path_chmod = tomoyo_path_chmod, + .path_chown = tomoyo_path_chown, + .path_chroot = tomoyo_path_chroot, + .sb_mount = tomoyo_sb_mount, + .sb_umount = tomoyo_sb_umount, + .sb_pivotroot = tomoyo_sb_pivotroot, +}; + +/* Lock for GC. */ +struct srcu_struct tomoyo_ss; + +static int __init tomoyo_init(void) +{ + struct cred *cred = (struct cred *) current_cred(); + + if (!security_module_enable(&tomoyo_security_ops)) + return 0; + /* register ourselves with the security framework */ + if (register_security(&tomoyo_security_ops) || + init_srcu_struct(&tomoyo_ss)) + panic("Failure registering TOMOYO Linux"); + printk(KERN_INFO "TOMOYO Linux initialized\n"); + cred->security = &tomoyo_kernel_domain; + tomoyo_mm_init(); + return 0; +} + +security_initcall(tomoyo_init); |