diff options
Diffstat (limited to 'bin/gensquashfs/src/apply_xattr.c')
| -rw-r--r-- | bin/gensquashfs/src/apply_xattr.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/bin/gensquashfs/src/apply_xattr.c b/bin/gensquashfs/src/apply_xattr.c new file mode 100644 index 0000000..cc03eab --- /dev/null +++ b/bin/gensquashfs/src/apply_xattr.c @@ -0,0 +1,220 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * apply_xattr.c + * + * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at> + */ +#include "mkfs.h" + +#ifdef HAVE_SYS_XATTR_H +static char *get_full_path(const char *prefix, tree_node_t *node) +{ + char *path = NULL, *new = NULL; + size_t path_len, prefix_len; + int ret; + + path = fstree_get_path(node); + if (path == NULL) + goto fail; + + ret = canonicalize_name(path); + assert(ret == 0); + + path_len = strlen(path); + prefix_len = strlen(prefix); + + while (prefix_len > 0 && prefix[prefix_len - 1] == '/') + --prefix_len; + + if (prefix_len > 0) { + new = realloc(path, path_len + prefix_len + 2); + if (new == NULL) + goto fail; + + path = new; + + memmove(path + prefix_len + 1, path, path_len + 1); + memcpy(path, prefix, prefix_len); + path[prefix_len] = '/'; + } + + return path; +fail: + perror("getting full path for xattr scan"); + free(path); + return NULL; +} + +static int xattr_from_path(sqfs_xattr_writer_t *xwr, const char *path) +{ + char *key, *value = NULL, *buffer = NULL; + ssize_t buflen, vallen, keylen; + int ret; + + buflen = llistxattr(path, NULL, 0); + if (buflen < 0) { + fprintf(stderr, "llistxattr %s: %s", path, strerror(errno)); + return -1; + } + + if (buflen == 0) + return 0; + + buffer = malloc(buflen); + if (buffer == NULL) { + perror("xattr name buffer"); + return -1; + } + + buflen = llistxattr(path, buffer, buflen); + if (buflen == -1) { + fprintf(stderr, "llistxattr %s: %s", path, strerror(errno)); + goto fail; + } + + key = buffer; + while (buflen > 0) { + vallen = lgetxattr(path, key, NULL, 0); + if (vallen == -1) { + fprintf(stderr, "lgetxattr %s: %s", + path, strerror(errno)); + goto fail; + } + + if (vallen > 0) { + value = calloc(1, vallen); + if (value == NULL) { + perror("allocating xattr value buffer"); + goto fail; + } + + vallen = lgetxattr(path, key, value, vallen); + if (vallen == -1) { + fprintf(stderr, "lgetxattr %s: %s\n", + path, strerror(errno)); + goto fail; + } + + ret = sqfs_xattr_writer_add_kv(xwr, key, value, vallen); + if (ret) { + sqfs_perror(path, + "storing xattr key-value pairs", + ret); + goto fail; + } + + free(value); + value = NULL; + } + + keylen = strlen(key) + 1; + buflen -= keylen; + key += keylen; + } + + free(buffer); + return 0; +fail: + free(value); + free(buffer); + return -1; +} +#endif + +static int xattr_xcan_dfs(const char *path_prefix, void *selinux_handle, + sqfs_xattr_writer_t *xwr, bool scan_xattr, void *xattr_map, + tree_node_t *node) +{ + char *path = NULL; + int ret; + + ret = sqfs_xattr_writer_begin(xwr, 0); + if (ret) { + sqfs_perror(node->name, "recoding xattr key-value pairs\n", + ret); + return -1; + } + +#ifdef HAVE_SYS_XATTR_H + if (scan_xattr) { + path = get_full_path(path_prefix, node); + if (path == NULL) + return -1; + + ret = xattr_from_path(xwr, path); + free(path); + path = NULL; + if (ret) { + ret = -1; + goto out; + } + } +#else + (void)path_prefix; +#endif + + if (selinux_handle != NULL || xattr_map != NULL) { + path = fstree_get_path(node); + + if (path == NULL) { + perror("reconstructing absolute path"); + ret = -1; + goto out; + } + } + + if (xattr_map != NULL) { + ret = xattr_apply_map_file(path, xattr_map, xwr); + + if (ret) { + ret = -1; + goto out; + } + } + + if (selinux_handle != NULL) { + ret = selinux_relable_node(selinux_handle, xwr, node, path); + + if (ret) { + ret = -1; + goto out; + } + } + + if (sqfs_xattr_writer_end(xwr, &node->xattr_idx)) { + sqfs_perror(node->name, "completing xattr key-value pairs", + ret); + ret = -1; + goto out; + } + + if (S_ISDIR(node->mode)) { + node = node->data.children; + + while (node != NULL) { + if (xattr_xcan_dfs(path_prefix, selinux_handle, xwr, + scan_xattr, xattr_map, node)) { + ret = -1; + goto out; + } + + node = node->next; + } + } + +out: + free(path); + return ret; +} + +int apply_xattrs(fstree_t *fs, const char *path, void *selinux_handle, + void *xattr_map, sqfs_xattr_writer_t *xwr, bool scan_xattr) +{ + if (xwr == NULL) + return 0; + + if (selinux_handle == NULL && !scan_xattr && xattr_map == NULL) + return 0; + + return xattr_xcan_dfs(path, selinux_handle, xwr, scan_xattr, xattr_map, fs->root); +} |