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-rw-r--r--grub-core/fs/cpio.c381
1 files changed, 381 insertions, 0 deletions
diff --git a/grub-core/fs/cpio.c b/grub-core/fs/cpio.c
new file mode 100644
index 0000000..a7ccfbd
--- /dev/null
+++ b/grub-core/fs/cpio.c
@@ -0,0 +1,381 @@
+/* cpio.c - cpio and tar filesystem. */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2007,2008,2009 Free Software Foundation, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/file.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/disk.h>
+#include <grub/dl.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+#ifndef MODE_USTAR
+/* cpio support */
+#define MAGIC_BCPIO 070707
+struct head
+{
+ grub_uint16_t magic;
+ grub_uint16_t dev;
+ grub_uint16_t ino;
+ grub_uint16_t mode;
+ grub_uint16_t uid;
+ grub_uint16_t gid;
+ grub_uint16_t nlink;
+ grub_uint16_t rdev;
+ grub_uint16_t mtime_1;
+ grub_uint16_t mtime_2;
+ grub_uint16_t namesize;
+ grub_uint16_t filesize_1;
+ grub_uint16_t filesize_2;
+} __attribute__ ((packed));
+#else
+/* tar support */
+#define MAGIC_USTAR "ustar"
+struct head
+{
+ char name[100];
+ char mode[8];
+ char uid[8];
+ char gid[8];
+ char size[12];
+ char mtime[12];
+ char chksum[8];
+ char typeflag;
+ char linkname[100];
+ char magic[6];
+ char version[2];
+ char uname[32];
+ char gname[32];
+ char devmajor[8];
+ char devminor[8];
+ char prefix[155];
+} __attribute__ ((packed));
+#endif
+
+struct grub_cpio_data
+{
+ grub_disk_t disk;
+ grub_uint32_t hofs;
+ grub_uint32_t dofs;
+ grub_uint32_t size;
+};
+
+static grub_dl_t my_mod;
+
+static grub_err_t
+grub_cpio_find_file (struct grub_cpio_data *data, char **name,
+ grub_uint32_t * ofs)
+{
+#ifndef MODE_USTAR
+ struct head hd;
+
+ if (grub_disk_read
+ (data->disk, 0, data->hofs, sizeof (hd), &hd))
+ return grub_errno;
+
+ if (hd.magic != MAGIC_BCPIO)
+ return grub_error (GRUB_ERR_BAD_FS, "invalid cpio archive");
+
+ data->size = (((grub_uint32_t) hd.filesize_1) << 16) + hd.filesize_2;
+
+ if (hd.namesize & 1)
+ hd.namesize++;
+
+ if ((*name = grub_malloc (hd.namesize)) == NULL)
+ return grub_errno;
+
+ if (grub_disk_read (data->disk, 0, data->hofs + sizeof (hd),
+ hd.namesize, *name))
+ {
+ grub_free (*name);
+ return grub_errno;
+ }
+
+ if (data->size == 0 && hd.mode == 0 && hd.namesize == 11 + 1
+ && ! grub_memcmp(*name, "TRAILER!!!", 11))
+ {
+ *ofs = 0;
+ return GRUB_ERR_NONE;
+ }
+
+ data->dofs = data->hofs + sizeof (hd) + hd.namesize;
+ *ofs = data->dofs + data->size;
+ if (data->size & 1)
+ (*ofs)++;
+#else
+ struct head hd;
+
+ if (grub_disk_read
+ (data->disk, 0, data->hofs, sizeof (hd), &hd))
+ return grub_errno;
+
+ if (!hd.name[0])
+ {
+ *ofs = 0;
+ return GRUB_ERR_NONE;
+ }
+
+ if (grub_memcmp (hd.magic, MAGIC_USTAR, sizeof (MAGIC_USTAR) - 1))
+ return grub_error (GRUB_ERR_BAD_FS, "invalid tar archive");
+
+ if ((*name = grub_strdup (hd.name)) == NULL)
+ return grub_errno;
+
+ data->size = grub_strtoul (hd.size, NULL, 8);
+ data->dofs = data->hofs + GRUB_DISK_SECTOR_SIZE;
+ *ofs = data->dofs + ((data->size + GRUB_DISK_SECTOR_SIZE - 1) &
+ ~(GRUB_DISK_SECTOR_SIZE - 1));
+#endif
+ return GRUB_ERR_NONE;
+}
+
+static struct grub_cpio_data *
+grub_cpio_mount (grub_disk_t disk)
+{
+ struct head hd;
+ struct grub_cpio_data *data;
+
+ if (grub_disk_read (disk, 0, 0, sizeof (hd), &hd))
+ goto fail;
+
+#ifndef MODE_USTAR
+ if (hd.magic != MAGIC_BCPIO)
+#else
+ if (grub_memcmp (hd.magic, MAGIC_USTAR,
+ sizeof (MAGIC_USTAR) - 1))
+#endif
+ goto fail;
+
+ data = (struct grub_cpio_data *) grub_malloc (sizeof (*data));
+ if (!data)
+ goto fail;
+
+ data->disk = disk;
+
+ return data;
+
+fail:
+ grub_error (GRUB_ERR_BAD_FS, "not a "
+#ifdef MODE_USTAR
+ "tar"
+#else
+ "cpio"
+#endif
+ " filesystem");
+ return 0;
+}
+
+static grub_err_t
+grub_cpio_dir (grub_device_t device, const char *path,
+ int (*hook) (const char *filename,
+ const struct grub_dirhook_info *info))
+{
+ struct grub_cpio_data *data;
+ grub_uint32_t ofs;
+ char *prev, *name;
+ const char *np;
+ int len;
+
+ grub_dl_ref (my_mod);
+
+ prev = 0;
+
+ data = grub_cpio_mount (device->disk);
+ if (!data)
+ goto fail;
+
+ np = path + 1;
+ len = grub_strlen (path) - 1;
+
+ data->hofs = 0;
+ while (1)
+ {
+ if (grub_cpio_find_file (data, &name, &ofs))
+ goto fail;
+
+ if (!ofs)
+ break;
+
+ if (grub_memcmp (np, name, len) == 0)
+ {
+ char *p, *n;
+
+ n = name + len;
+ if (*n == '/')
+ n++;
+
+ p = grub_strchr (name + len, '/');
+ if (p)
+ *p = 0;
+
+ if ((!prev) || (grub_strcmp (prev, name) != 0))
+ {
+ struct grub_dirhook_info info;
+ grub_memset (&info, 0, sizeof (info));
+ info.dir = (p != NULL);
+
+ hook (name + len, &info);
+ if (prev)
+ grub_free (prev);
+ prev = name;
+ }
+ else
+ grub_free (name);
+ }
+ data->hofs = ofs;
+ }
+
+fail:
+
+ if (prev)
+ grub_free (prev);
+
+ if (data)
+ grub_free (data);
+
+ grub_dl_unref (my_mod);
+
+ return grub_errno;
+}
+
+static grub_err_t
+grub_cpio_open (grub_file_t file, const char *name)
+{
+ struct grub_cpio_data *data;
+ grub_uint32_t ofs;
+ char *fn;
+ int i, j;
+
+ grub_dl_ref (my_mod);
+
+ data = grub_cpio_mount (file->device->disk);
+ if (!data)
+ goto fail;
+
+ data->hofs = 0;
+ while (1)
+ {
+ if (grub_cpio_find_file (data, &fn, &ofs))
+ goto fail;
+
+ if (!ofs)
+ {
+ grub_error (GRUB_ERR_FILE_NOT_FOUND, "file not found");
+ break;
+ }
+
+ /* Compare NAME and FN by hand in order to cope with duplicate
+ slashes. */
+ i = 0;
+ j = 0;
+ while (name[i] == '/')
+ i++;
+ while (1)
+ {
+ if (name[i] != fn[j])
+ goto no_match;
+
+ if (name[i] == '\0')
+ break;
+
+ while (name[i] == '/' && name[i+1] == '/')
+ i++;
+
+ i++;
+ j++;
+ }
+
+ if (name[i] != fn[j])
+ goto no_match;
+
+ file->data = data;
+ file->size = data->size;
+ grub_free (fn);
+
+ return GRUB_ERR_NONE;
+
+ no_match:
+
+ grub_free (fn);
+ data->hofs = ofs;
+ }
+
+fail:
+
+ if (data)
+ grub_free (data);
+
+ grub_dl_unref (my_mod);
+
+ return grub_errno;
+}
+
+static grub_ssize_t
+grub_cpio_read (grub_file_t file, char *buf, grub_size_t len)
+{
+ struct grub_cpio_data *data;
+
+ data = file->data;
+ return (grub_disk_read (data->disk, 0, data->dofs + file->offset,
+ len, buf)) ? -1 : (grub_ssize_t) len;
+}
+
+static grub_err_t
+grub_cpio_close (grub_file_t file)
+{
+ grub_free (file->data);
+
+ grub_dl_unref (my_mod);
+
+ return grub_errno;
+}
+
+static struct grub_fs grub_cpio_fs = {
+#ifdef MODE_USTAR
+ .name = "tarfs",
+#else
+ .name = "cpiofs",
+#endif
+ .dir = grub_cpio_dir,
+ .open = grub_cpio_open,
+ .read = grub_cpio_read,
+ .close = grub_cpio_close,
+#ifdef GRUB_UTIL
+ .reserved_first_sector = 0,
+#endif
+};
+
+#ifdef MODE_USTAR
+GRUB_MOD_INIT (tar)
+#else
+GRUB_MOD_INIT (cpio)
+#endif
+{
+ grub_fs_register (&grub_cpio_fs);
+ my_mod = mod;
+}
+
+#ifdef MODE_USTAR
+GRUB_MOD_FINI (tar)
+#else
+GRUB_MOD_FINI (cpio)
+#endif
+{
+ grub_fs_unregister (&grub_cpio_fs);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-17 17:34:40 +0000