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-rw-r--r--libtar/extract.c666
1 files changed, 666 insertions, 0 deletions
diff --git a/libtar/extract.c b/libtar/extract.c
new file mode 100644
index 000000000..fcd403a04
--- /dev/null
+++ b/libtar/extract.c
@@ -0,0 +1,666 @@
+/*
+** Copyright 1998-2003 University of Illinois Board of Trustees
+** Copyright 1998-2003 Mark D. Roth
+** All rights reserved.
+**
+** extract.c - libtar code to extract a file from a tar archive
+**
+** Mark D. Roth <roth@uiuc.edu>
+** Campus Information Technologies and Educational Services
+** University of Illinois at Urbana-Champaign
+*/
+
+#include <internal.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <utime.h>
+
+#include <sys/capability.h>
+#include <sys/xattr.h>
+#include <linux/xattr.h>
+
+#ifdef STDC_HEADERS
+# include <stdlib.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#include <selinux/selinux.h>
+
+#ifdef HAVE_EXT4_CRYPT
+# include "ext4crypt_tar.h"
+#endif
+#include "android_utils.h"
+
+const unsigned long long progress_size = (unsigned long long)(T_BLOCKSIZE);
+
+static int
+tar_set_file_perms(TAR *t, const char *realname)
+{
+ mode_t mode;
+ uid_t uid;
+ gid_t gid;
+ struct utimbuf ut;
+ const char *filename;
+ char *pn;
+
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ mode = th_get_mode(t);
+ uid = th_get_uid(t);
+ gid = th_get_gid(t);
+ ut.modtime = ut.actime = th_get_mtime(t);
+
+#ifdef DEBUG
+ printf("tar_set_file_perms(): setting perms: %s (mode %04o, uid %d, gid %d)\n",
+ filename, mode, uid, gid);
+#endif
+
+ /* change owner/group */
+ if (geteuid() == 0)
+#ifdef HAVE_LCHOWN
+ if (lchown(filename, uid, gid) == -1)
+ {
+# ifdef DEBUG
+ fprintf(stderr, "lchown(\"%s\", %d, %d): %s\n",
+ filename, uid, gid, strerror(errno));
+# endif
+#else /* ! HAVE_LCHOWN */
+ if (!TH_ISSYM(t) && chown(filename, uid, gid) == -1)
+ {
+# ifdef DEBUG
+ fprintf(stderr, "chown(\"%s\", %d, %d): %s\n",
+ filename, uid, gid, strerror(errno));
+# endif
+#endif /* HAVE_LCHOWN */
+ return -1;
+ }
+
+ /* change access/modification time */
+ if (!TH_ISSYM(t) && utime(filename, &ut) == -1)
+ {
+#ifdef DEBUG
+ perror("utime()");
+#endif
+ return -1;
+ }
+
+ /* change permissions */
+ if (!TH_ISSYM(t) && chmod(filename, mode) == -1)
+ {
+#ifdef DEBUG
+ perror("chmod()");
+#endif
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/* switchboard */
+int
+tar_extract_file(TAR *t, const char *realname, const char *prefix, const int *progress_fd)
+{
+ int i;
+#ifdef LIBTAR_FILE_HASH
+ char *lnp;
+ char *pn;
+ int pathname_len;
+ int realname_len;
+#endif
+
+ if (t->options & TAR_NOOVERWRITE)
+ {
+ struct stat s;
+
+ if (lstat(realname, &s) == 0 || errno != ENOENT)
+ {
+ errno = EEXIST;
+ return -1;
+ }
+ }
+
+ if (TH_ISDIR(t))
+ {
+ i = tar_extract_dir(t, realname);
+ if (i == 1)
+ i = 0;
+ }
+ else if (TH_ISLNK(t))
+ i = tar_extract_hardlink(t, realname, prefix);
+ else if (TH_ISSYM(t))
+ i = tar_extract_symlink(t, realname);
+ else if (TH_ISCHR(t))
+ i = tar_extract_chardev(t, realname);
+ else if (TH_ISBLK(t))
+ i = tar_extract_blockdev(t, realname);
+ else if (TH_ISFIFO(t))
+ i = tar_extract_fifo(t, realname);
+ else /* if (TH_ISREG(t)) */
+ i = tar_extract_regfile(t, realname, progress_fd);
+
+ if (i != 0) {
+ fprintf(stderr, "tar_extract_file(): failed to extract %s !!!\n", realname);
+ return i;
+ }
+
+ i = tar_set_file_perms(t, realname);
+ if (i != 0) {
+ fprintf(stderr, "tar_extract_file(): failed to set permissions on %s !!!\n", realname);
+ return i;
+ }
+
+ if((t->options & TAR_STORE_SELINUX) && t->th_buf.selinux_context != NULL)
+ {
+#ifdef DEBUG
+ printf("tar_extract_file(): restoring SELinux context %s to file %s\n", t->th_buf.selinux_context, realname);
+#endif
+ if (lsetfilecon(realname, t->th_buf.selinux_context) < 0)
+ fprintf(stderr, "tar_extract_file(): failed to restore SELinux context %s to file %s !!!\n", t->th_buf.selinux_context, realname);
+ }
+
+ if((t->options & TAR_STORE_POSIX_CAP) && t->th_buf.has_cap_data)
+ {
+#if 1 //def DEBUG
+ printf("tar_extract_file(): restoring posix capabilities to file %s\n", realname);
+ print_caps(&t->th_buf.cap_data);
+#endif
+ if (setxattr(realname, XATTR_NAME_CAPS, &t->th_buf.cap_data, sizeof(struct vfs_cap_data), 0) < 0)
+ fprintf(stderr, "tar_extract_file(): failed to restore posix capabilities to file %s !!!\n", realname);
+ }
+
+#ifdef LIBTAR_FILE_HASH
+ pn = th_get_pathname(t);
+ pathname_len = strlen(pn) + 1;
+ realname_len = strlen(realname) + 1;
+ lnp = (char *)calloc(1, pathname_len + realname_len);
+ if (lnp == NULL)
+ return -1;
+ strcpy(&lnp[0], pn);
+ strcpy(&lnp[pathname_len], realname);
+#ifdef DEBUG
+ printf("tar_extract_file(): calling libtar_hash_add(): key=\"%s\", "
+ "value=\"%s\"\n", pn, realname);
+#endif
+ if (libtar_hash_add(t->h, lnp) != 0)
+ return -1;
+ free(lnp);
+#endif
+
+ return 0;
+}
+
+
+/* extract regular file */
+int
+tar_extract_regfile(TAR *t, const char *realname, const int *progress_fd)
+{
+ int64_t size, i;
+ ssize_t k;
+ int fdout;
+ char buf[T_BLOCKSIZE];
+ const char *filename;
+ char *pn;
+
+#ifdef DEBUG
+ printf(" ==> tar_extract_regfile(realname=\"%s\")\n", realname);
+#endif
+
+ if (!TH_ISREG(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ size = th_get_size(t);
+
+ if (mkdirhier(dirname(filename)) == -1)
+ return -1;
+
+ printf(" ==> extracting: %s (file size %lld bytes)\n",
+ filename, size);
+
+ fdout = open(filename, O_WRONLY | O_CREAT | O_TRUNC
+#ifdef O_BINARY
+ | O_BINARY
+#endif
+ , 0666);
+ if (fdout == -1)
+ {
+#ifdef DEBUG
+ perror("open()");
+#endif
+ return -1;
+ }
+
+ /* extract the file */
+ for (i = size; i > 0; i -= T_BLOCKSIZE)
+ {
+ k = tar_block_read(t, buf);
+ if (k != T_BLOCKSIZE)
+ {
+ if (k != -1)
+ errno = EINVAL;
+ close(fdout);
+ return -1;
+ }
+
+ /* write block to output file */
+ if (write(fdout, buf,
+ ((i > T_BLOCKSIZE) ? T_BLOCKSIZE : i)) == -1)
+ {
+ close(fdout);
+ return -1;
+ }
+ else
+ {
+ if (*progress_fd != 0)
+ write(*progress_fd, &progress_size, sizeof(progress_size));
+ }
+ }
+
+ /* close output file */
+ if (close(fdout) == -1)
+ return -1;
+
+#ifdef DEBUG
+ printf("### done extracting %s\n", filename);
+#endif
+
+ return 0;
+}
+
+
+/* skip regfile */
+int
+tar_skip_regfile(TAR *t)
+{
+ int64_t size, i;
+ ssize_t k;
+ char buf[T_BLOCKSIZE];
+
+ if (!TH_ISREG(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ size = th_get_size(t);
+ for (i = size; i > 0; i -= T_BLOCKSIZE)
+ {
+ k = tar_block_read(t, buf);
+ if (k != T_BLOCKSIZE)
+ {
+ if (k != -1)
+ errno = EINVAL;
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+
+/* hardlink */
+int
+tar_extract_hardlink(TAR * t, const char *realname, const char *prefix)
+{
+ const char *filename;
+ char *pn;
+ char *linktgt = NULL;
+ char *newtgt = NULL;
+ char *lnp;
+ libtar_hashptr_t hp;
+
+ if (!TH_ISLNK(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ if (mkdirhier(dirname(filename)) == -1)
+ return -1;
+ if (unlink(filename) == -1 && errno != ENOENT)
+ return -1;
+ libtar_hashptr_reset(&hp);
+ if (libtar_hash_getkey(t->h, &hp, th_get_linkname(t),
+ (libtar_matchfunc_t)libtar_str_match) != 0)
+ {
+ lnp = (char *)libtar_hashptr_data(&hp);
+ linktgt = &lnp[strlen(lnp) + 1];
+ }
+ else
+ linktgt = th_get_linkname(t);
+
+ newtgt = strdup(linktgt);
+ sprintf(linktgt, "%s/%s", prefix, newtgt);
+
+ printf(" ==> extracting: %s (link to %s)\n", filename, linktgt);
+
+ if (link(linktgt, filename) == -1)
+ {
+ fprintf(stderr, "tar_extract_hardlink(): failed restore of hardlink '%s' but returning as if nothing bad happened\n", filename);
+ return 0; // Used to be -1
+ }
+
+ return 0;
+}
+
+
+/* symlink */
+int
+tar_extract_symlink(TAR *t, const char *realname)
+{
+ const char *filename;
+ char *pn;
+
+ if (!TH_ISSYM(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ if (mkdirhier(dirname(filename)) == -1)
+ return -1;
+
+ if (unlink(filename) == -1 && errno != ENOENT)
+ return -1;
+
+ printf(" ==> extracting: %s (symlink to %s)\n",
+ filename, th_get_linkname(t));
+
+ if (symlink(th_get_linkname(t), filename) == -1)
+ {
+#ifdef DEBUG
+ perror("symlink()");
+#endif
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/* character device */
+int
+tar_extract_chardev(TAR *t, const char *realname)
+{
+ mode_t mode;
+ unsigned long devmaj, devmin;
+ const char *filename;
+ char *pn;
+
+ if (!TH_ISCHR(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ mode = th_get_mode(t);
+ devmaj = th_get_devmajor(t);
+ devmin = th_get_devminor(t);
+
+ if (mkdirhier(dirname(filename)) == -1)
+ return -1;
+
+ printf(" ==> extracting: %s (character device %ld,%ld)\n",
+ filename, devmaj, devmin);
+
+ if (mknod(filename, mode | S_IFCHR,
+ compat_makedev(devmaj, devmin)) == -1)
+ {
+ fprintf(stderr, "tar_extract_chardev(): failed restore of character device '%s' but returning as if nothing bad happened\n", filename);
+ return 0; // Used to be -1
+ }
+
+ return 0;
+}
+
+
+/* block device */
+int
+tar_extract_blockdev(TAR *t, const char *realname)
+{
+ mode_t mode;
+ unsigned long devmaj, devmin;
+ const char *filename;
+ char *pn;
+
+ if (!TH_ISBLK(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ mode = th_get_mode(t);
+ devmaj = th_get_devmajor(t);
+ devmin = th_get_devminor(t);
+
+ if (mkdirhier(dirname(filename)) == -1)
+ return -1;
+
+ printf(" ==> extracting: %s (block device %ld,%ld)\n",
+ filename, devmaj, devmin);
+
+ if (mknod(filename, mode | S_IFBLK,
+ compat_makedev(devmaj, devmin)) == -1)
+ {
+ fprintf(stderr, "tar_extract_blockdev(): failed restore of block device '%s' but returning as if nothing bad happened\n", filename);
+ return 0; // Used to be -1
+ }
+
+ return 0;
+}
+
+/* directory */
+int
+tar_extract_dir(TAR *t, const char *realname)
+{
+ mode_t mode;
+ const char *filename;
+ char *pn;
+
+ if (!TH_ISDIR(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ mode = th_get_mode(t);
+
+ if (mkdirhier(dirname(filename)) == -1)
+ return -1;
+
+ printf(" ==> extracting: %s (mode %04o, directory)\n", filename,
+ mode);
+
+ if (mkdir(filename, mode) == -1)
+ {
+ if (errno == EEXIST)
+ {
+ if (chmod(filename, mode) == -1)
+ {
+#ifdef DEBUG
+ perror("chmod()");
+#endif
+ return -1;
+ }
+ else
+ {
+#if 1 //def DEBUG
+ puts(" *** using existing directory");
+#endif
+ return 1;
+ }
+ }
+ else
+ {
+#ifdef DEBUG
+ perror("mkdir()");
+#endif
+ return -1;
+ }
+ }
+
+ if (t->options & TAR_STORE_ANDROID_USER_XATTR)
+ {
+ if (t->th_buf.has_user_default) {
+#if 1 //def DEBUG
+ printf("tar_extract_file(): restoring android user.default xattr to %s\n", realname);
+#endif
+ if (setxattr(realname, "user.default", NULL, 0, 0) < 0) {
+ fprintf(stderr, "tar_extract_file(): failed to restore android user.default to file %s !!!\n", realname);
+ return -1;
+ }
+ }
+ if (t->th_buf.has_user_cache) {
+#if 1 //def DEBUG
+ printf("tar_extract_file(): restoring android user.inode_cache xattr to %s\n", realname);
+#endif
+ if (write_path_inode(realname, "cache", "user.inode_cache"))
+ return -1;
+ }
+ if (t->th_buf.has_user_code_cache) {
+#if 1 //def DEBUG
+ printf("tar_extract_file(): restoring android user.inode_code_cache xattr to %s\n", realname);
+#endif
+ if (write_path_inode(realname, "code_cache", "user.inode_code_cache"))
+ return -1;
+ }
+ }
+
+#ifdef HAVE_EXT4_CRYPT
+ if(t->th_buf.eep != NULL)
+ {
+#ifdef DEBUG
+ printf("tar_extract_file(): restoring EXT4 crypt policy %s to dir %s\n", t->th_buf.eep->master_key_descriptor, realname);
+#endif
+ char binary_policy[EXT4_KEY_DESCRIPTOR_SIZE];
+ if (!lookup_ref_tar(t->th_buf.eep->master_key_descriptor, &binary_policy[0])) {
+ printf("error looking up proper e4crypt policy for '%s' - %s\n", realname, t->th_buf.eep->master_key_descriptor);
+ return -1;
+ }
+ char policy_hex[EXT4_KEY_DESCRIPTOR_SIZE_HEX];
+ policy_to_hex(binary_policy, policy_hex);
+ printf("restoring policy %s > '%s' to '%s'\n", t->th_buf.eep->master_key_descriptor, policy_hex, realname);
+ memcpy(&t->th_buf.eep->master_key_descriptor, binary_policy, EXT4_KEY_DESCRIPTOR_SIZE);
+ if (!e4crypt_policy_set_struct(realname, t->th_buf.eep))
+ {
+ printf("tar_extract_file(): failed to restore EXT4 crypt policy to dir '%s' '%s'!!!\n", realname, policy_hex);
+ //return -1; // This may not be an error in some cases, so log and ignore
+ }
+ }
+#endif
+
+ return 0;
+}
+
+
+/* FIFO */
+int
+tar_extract_fifo(TAR *t, const char *realname)
+{
+ mode_t mode;
+ const char *filename;
+ char *pn;
+
+ if (!TH_ISFIFO(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ pn = th_get_pathname(t);
+ filename = (realname ? realname : pn);
+ mode = th_get_mode(t);
+
+ if (mkdirhier(dirname(filename)) == -1)
+ return -1;
+
+
+ printf(" ==> extracting: %s (fifo)\n", filename);
+
+ if (mkfifo(filename, mode) == -1)
+ {
+#ifdef DEBUG
+ perror("mkfifo()");
+#endif
+ return -1;
+ }
+
+ return 0;
+}
+
+/* extract file contents from a tarchive */
+int
+tar_extract_file_contents(TAR *t, void *buf, size_t *lenp)
+{
+ char block[T_BLOCKSIZE];
+ int64_t size, i;
+ ssize_t k;
+
+#ifdef DEBUG
+ printf(" ==> tar_extract_file_contents\n");
+#endif
+
+ if (!TH_ISREG(t))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ size = th_get_size(t);
+ if ((uint64_t)size > *lenp)
+ {
+ errno = ENOSPC;
+ return -1;
+ }
+
+ /* extract the file */
+ for (i = size; i >= T_BLOCKSIZE; i -= T_BLOCKSIZE)
+ {
+ k = tar_block_read(t, buf);
+ if (k != T_BLOCKSIZE)
+ {
+ if (k != -1)
+ errno = EINVAL;
+ return -1;
+ }
+ buf = (char *)buf + T_BLOCKSIZE;
+ }
+ if (i > 0) {
+ k = tar_block_read(t, block);
+ if (k != T_BLOCKSIZE)
+ {
+ if (k != -1)
+ errno = EINVAL;
+ return -1;
+ }
+ memcpy(buf, block, i);
+ }
+ *lenp = (size_t)size;
+
+#ifdef DEBUG
+ printf("### done extracting contents\n");
+#endif
+ return 0;
+}
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