unix_apply.c: support applying extended attributes
authorEric Biggers <ebiggers3@gmail.com>
Tue, 27 Dec 2016 23:24:55 +0000 (17:24 -0600)
committerEric Biggers <ebiggers3@gmail.com>
Wed, 28 Dec 2016 04:30:51 +0000 (22:30 -0600)
src/unix_apply.c

index b17bd35..3b31e19 100644 (file)
@@ -29,6 +29,9 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/types.h>
+#ifdef HAVE_SYS_XATTR_H
+#  include <sys/xattr.h>
+#endif
 #include <unistd.h>
 
 #include "wimlib/apply.h"
@@ -40,6 +43,7 @@
 #include "wimlib/reparse.h"
 #include "wimlib/timestamp.h"
 #include "wimlib/unix_data.h"
+#include "wimlib/xattr.h"
 
 /* We don't require O_NOFOLLOW, but the advantage of having it is that if we
  * need to extract a file to a location at which there exists a symbolic link,
@@ -60,6 +64,9 @@ unix_get_supported_features(const char *target,
        supported_features->unix_data = 1;
        supported_features->timestamps = 1;
        supported_features->case_sensitive_filenames = 1;
+#ifdef HAVE_XATTR_SUPPORT
+       supported_features->linux_xattrs = 1;
+#endif
        return 0;
 }
 
@@ -261,6 +268,109 @@ unix_set_mode(int fd, const char *path, mode_t mode)
        return WIMLIB_ERR_SET_SECURITY;
 }
 
+#ifdef HAVE_XATTR_SUPPORT
+/* Apply extended attributes to a file */
+static int
+apply_linux_xattrs(int fd, const struct wim_inode *inode,
+                  const char *path, struct unix_apply_ctx *ctx,
+                  const void *entries, size_t entries_size)
+{
+       const void * const entries_end = entries + entries_size;
+       char name[XATTR_NAME_MAX + 1];
+
+       for (const struct wimlib_xattr_entry *entry = entries;
+            (void *)entry < entries_end; entry = xattr_entry_next(entry))
+       {
+               u16 name_len;
+               const void *value;
+               u32 value_len;
+               int res;
+
+               if (!valid_xattr_entry(entry, entries_end - (void *)entry)) {
+                       if (!path) {
+                               path = unix_build_inode_extraction_path(inode,
+                                                                       ctx);
+                       }
+                       ERROR("\"%s\": extended attribute is corrupt", path);
+                       return WIMLIB_ERR_INVALID_XATTR;
+               }
+               name_len = le16_to_cpu(entry->name_len);
+               memcpy(name, entry->name, name_len);
+               name[name_len] = '\0';
+
+               value = entry->name + name_len;
+               value_len = le32_to_cpu(entry->value_len);
+
+               if (fd >= 0)
+                       res = fsetxattr(fd, name, value, value_len, 0);
+               else
+                       res = lsetxattr(path, name, value, value_len, 0);
+
+               if (unlikely(res != 0)) {
+                       if (!path) {
+                               path = unix_build_inode_extraction_path(inode,
+                                                                       ctx);
+                       }
+                       if (is_security_xattr(name) &&
+                           (ctx->common.extract_flags &
+                            WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
+                       {
+                               ERROR_WITH_ERRNO("\"%s\": unable to set extended attribute \"%s\"",
+                                                path, name);
+                               return WIMLIB_ERR_SET_XATTR;
+                       }
+                       WARNING_WITH_ERRNO("\"%s\": unable to set extended attribute \"%s\"",
+                                          path, name);
+               }
+       }
+       return 0;
+}
+#endif /* HAVE_XATTR_SUPPORT */
+
+/* Apply standard UNIX permissions (uid, gid, and mode) to a file */
+static int
+apply_unix_permissions(int fd, const struct wim_inode *inode,
+                      const char *path, struct unix_apply_ctx *ctx,
+                      const struct wimlib_unix_data *dat)
+{
+       int ret;
+
+       ret = unix_set_owner_and_group(fd, path, dat->uid, dat->gid);
+       if (ret) {
+               if (!path)
+                       path = unix_build_inode_extraction_path(inode, ctx);
+               if (ctx->common.extract_flags &
+                   WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
+               {
+                       ERROR_WITH_ERRNO("\"%s\": unable to set uid=%"PRIu32" and gid=%"PRIu32,
+                                        path, dat->uid, dat->gid);
+                       return ret;
+               }
+               WARNING_WITH_ERRNO("\"%s\": unable to set uid=%"PRIu32" and gid=%"PRIu32,
+                                  path, dat->uid, dat->gid);
+       }
+
+       if (!inode_is_symlink(inode)) {
+               ret = unix_set_mode(fd, path, dat->mode);
+               if (ret) {
+                       if (!path)
+                               path = unix_build_inode_extraction_path(inode,
+                                                                       ctx);
+                       if (ctx->common.extract_flags &
+                           WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
+                       {
+                               ERROR_WITH_ERRNO("\"%s\": unable to set mode=0%"PRIo32,
+                                                path, dat->mode);
+                               return ret;
+                       }
+                       WARNING_WITH_ERRNO("\"%s\": unable to set mode=0%"PRIo32,
+                                          path, dat->mode);
+               }
+       }
+
+       return 0;
+}
+
 /*
  * Set metadata on an extracted file.
  *
@@ -274,57 +384,33 @@ unix_set_metadata(int fd, const struct wim_inode *inode,
                  const char *path, struct unix_apply_ctx *ctx)
 {
        int ret;
-       struct wimlib_unix_data unix_data;
 
        if (fd < 0 && !path)
                path = unix_build_inode_extraction_path(inode, ctx);
 
-       if ((ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA)
-           && inode_get_unix_data(inode, &unix_data))
-       {
-               u32 uid = unix_data.uid;
-               u32 gid = unix_data.gid;
-               u32 mode = unix_data.mode;
+       if (ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
+               struct wimlib_unix_data dat;
+       #ifdef HAVE_XATTR_SUPPORT
+               const void *entries;
+               u32 entries_size;
 
-               ret = unix_set_owner_and_group(fd, path, uid, gid);
-               if (ret) {
-                       if (!path)
-                               path = unix_build_inode_extraction_path(inode, ctx);
-                       if (ctx->common.extract_flags &
-                           WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
-                       {
-                               ERROR_WITH_ERRNO("Can't set uid=%"PRIu32" and "
-                                                "gid=%"PRIu32" on \"%s\"",
-                                                uid, gid, path);
+               entries = inode_get_linux_xattrs(inode, &entries_size);
+               if (entries) {
+                       ret = apply_linux_xattrs(fd, inode, path, ctx,
+                                                entries, entries_size);
+                       if (ret)
                                return ret;
-                       } else {
-                               WARNING_WITH_ERRNO("Can't set uid=%"PRIu32" and "
-                                                  "gid=%"PRIu32" on \"%s\"",
-                                                  uid, gid, path);
-                       }
                }
-
-               ret = 0;
-               if (!inode_is_symlink(inode))
-                       ret = unix_set_mode(fd, path, mode);
-               if (ret) {
-                       if (!path)
-                               path = unix_build_inode_extraction_path(inode, ctx);
-                       if (ctx->common.extract_flags &
-                           WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
-                       {
-                               ERROR_WITH_ERRNO("Can't set mode=0%"PRIo32" "
-                                                "on \"%s\"", mode, path);
+       #endif
+               if (inode_get_unix_data(inode, &dat)) {
+                       ret = apply_unix_permissions(fd, inode, path, ctx,
+                                                    &dat);
+                       if (ret)
                                return ret;
-                       } else {
-                               WARNING_WITH_ERRNO("Can't set mode=0%"PRIo32" "
-                                                  "on \"%s\"", mode, path);
-                       }
                }
        }
 
-       ret = unix_set_timestamps(fd, path,
-                                 inode->i_last_access_time,
+       ret = unix_set_timestamps(fd, path, inode->i_last_access_time,
                                  inode->i_last_write_time);
        if (ret) {
                if (!path)
@@ -332,12 +418,12 @@ unix_set_metadata(int fd, const struct wim_inode *inode,
                if (ctx->common.extract_flags &
                    WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS)
                {
-                       ERROR_WITH_ERRNO("Can't set timestamps on \"%s\"", path);
+                       ERROR_WITH_ERRNO("\"%s\": unable to set timestamps", path);
                        return ret;
-               } else {
-                       WARNING_WITH_ERRNO("Can't set timestamps on \"%s\"", path);
                }
+               WARNING_WITH_ERRNO("\"%s\": unable to set timestamps", path);
        }
+
        return 0;
 }