diff options
Diffstat (limited to 'bin/gensquashfs/dirscan.c')
-rw-r--r-- | bin/gensquashfs/dirscan.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/bin/gensquashfs/dirscan.c b/bin/gensquashfs/dirscan.c new file mode 100644 index 0000000..dbc862c --- /dev/null +++ b/bin/gensquashfs/dirscan.c @@ -0,0 +1,321 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * fstree_from_dir.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(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 + +#ifdef _WIN32 +int fstree_from_dir(fstree_t *fs, const char *path, void *selinux_handle, + sqfs_xattr_writer_t *xwr, unsigned int flags) +{ + (void)fs; (void)path; (void)selinux_handle; (void)xwr; (void)flags; + fputs("Packing a directory is not supported on Windows.\n", stderr); + return -1; +} +#else +static int xattr_xcan_dfs(const char *path_prefix, void *selinux_handle, + sqfs_xattr_writer_t *xwr, unsigned int flags, + tree_node_t *node) +{ + char *path; + int ret; + + ret = sqfs_xattr_writer_begin(xwr); + if (ret) { + sqfs_perror(node->name, "recoding xattr key-value pairs\n", + ret); + return -1; + } + +#ifdef HAVE_SYS_XATTR_H + if (flags & DIR_SCAN_READ_XATTR) { + path = get_full_path(path_prefix, node); + if (path == NULL) + return -1; + + ret = xattr_from_path(xwr, path); + free(path); + + if (ret) + return -1; + } +#else + (void)path_prefix; +#endif + + if (selinux_handle != NULL) { + path = fstree_get_path(node); + if (path == NULL) { + perror("reconstructing absolute path"); + return -1; + } + + ret = selinux_relable_node(selinux_handle, xwr, node, path); + free(path); + + if (ret) + return -1; + } + + if (sqfs_xattr_writer_end(xwr, &node->xattr_idx)) { + sqfs_perror(node->name, "completing xattr key-value pairs", + ret); + return -1; + } + + if (S_ISDIR(node->mode)) { + node = node->data.dir.children; + + while (node != NULL) { + if (xattr_xcan_dfs(path_prefix, selinux_handle, xwr, + flags, node)) { + return -1; + } + + node = node->next; + } + } + + return 0; +} + +static int populate_dir(int dir_fd, fstree_t *fs, tree_node_t *root, + dev_t devstart, unsigned int flags) +{ + char *extra = NULL; + struct dirent *ent; + struct stat sb; + tree_node_t *n; + int childfd; + DIR *dir; + + dir = fdopendir(dir_fd); + if (dir == NULL) { + perror("fdopendir"); + close(dir_fd); + return -1; + } + + /* XXX: fdopendir can dup and close dir_fd internally + and still be compliant with the spec. */ + dir_fd = dirfd(dir); + + for (;;) { + errno = 0; + ent = readdir(dir); + + if (ent == NULL) { + if (errno) { + perror("readdir"); + goto fail; + } + break; + } + + if (!strcmp(ent->d_name, "..") || !strcmp(ent->d_name, ".")) + continue; + + if (fstatat(dir_fd, ent->d_name, &sb, AT_SYMLINK_NOFOLLOW)) { + perror(ent->d_name); + goto fail; + } + + if ((flags & DIR_SCAN_ONE_FILESYSTEM) && sb.st_dev != devstart) + continue; + + if (S_ISLNK(sb.st_mode)) { + extra = calloc(1, sb.st_size + 1); + if (extra == NULL) + goto fail_rdlink; + + if (readlinkat(dir_fd, ent->d_name, + extra, sb.st_size) < 0) { + goto fail_rdlink; + } + + extra[sb.st_size] = '\0'; + } + + if (!(flags & DIR_SCAN_KEEP_TIME)) + sb.st_mtime = fs->defaults.st_mtime; + + n = fstree_mknode(root, ent->d_name, strlen(ent->d_name), + extra, &sb); + if (n == NULL) { + perror("creating tree node"); + goto fail; + } + + free(extra); + extra = NULL; + + if (S_ISDIR(n->mode)) { + childfd = openat(dir_fd, n->name, O_DIRECTORY | + O_RDONLY | O_CLOEXEC); + if (childfd < 0) { + perror(n->name); + goto fail; + } + + if (populate_dir(childfd, fs, n, devstart, flags)) + goto fail; + } + } + + closedir(dir); + return 0; +fail_rdlink: + perror("readlink"); +fail: + closedir(dir); + free(extra); + return -1; +} + +int fstree_from_dir(fstree_t *fs, const char *path, void *selinux_handle, + sqfs_xattr_writer_t *xwr, unsigned int flags) +{ + struct stat sb; + int fd; + + fd = open(path, O_DIRECTORY | O_RDONLY | O_CLOEXEC); + if (fd < 0) { + perror(path); + return -1; + } + + if (fstat(fd, &sb)) { + perror(path); + close(fd); + return -1; + } + + if (populate_dir(fd, fs, fs->root, sb.st_dev, flags)) + return -1; + + if (xwr != NULL && (selinux_handle != NULL || + (flags & DIR_SCAN_READ_XATTR))) { + if (xattr_xcan_dfs(path, selinux_handle, xwr, flags, fs->root)) + return -1; + } + + return 0; +} +#endif |