From 687e44297071c95004d47e389fc409b951a8f9ff Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Mon, 27 Apr 2020 20:19:46 +0200 Subject: Cleanup/fix: gensquashfs: split directory scanning from xattr scanning On the one hand, this commit cleanes the code a bit by splitting the "scan directory contents" code from the "scan xattrs from directory contents" and moving the later in a seperate file. On the other hand, the xattr scanning is now done *after* the fstree is post processed, which includes sorting it. This way, the xattrs are always added in a deterministic, reproducible order. Signed-off-by: David Oberhollenzer --- bin/Makemodule.am | 2 +- bin/gensquashfs/dirscan.c | 202 +--------------------------------------- bin/gensquashfs/dirscan_xattr.c | 200 +++++++++++++++++++++++++++++++++++++++ bin/gensquashfs/mkfs.c | 29 +++--- bin/gensquashfs/mkfs.h | 5 +- 5 files changed, 224 insertions(+), 214 deletions(-) create mode 100644 bin/gensquashfs/dirscan_xattr.c diff --git a/bin/Makemodule.am b/bin/Makemodule.am index 4199ac5..778636c 100644 --- a/bin/Makemodule.am +++ b/bin/Makemodule.am @@ -28,7 +28,7 @@ sqfsdiff_LDADD += $(PTHREAD_LIBS) gensquashfs_SOURCES = bin/gensquashfs/mkfs.c bin/gensquashfs/mkfs.h gensquashfs_SOURCES += bin/gensquashfs/options.c bin/gensquashfs/selinux.c -gensquashfs_SOURCES += bin/gensquashfs/dirscan.c +gensquashfs_SOURCES += bin/gensquashfs/dirscan.c bin/gensquashfs/dirscan_xattr.c gensquashfs_LDADD = libcommon.a libsquashfs.la libfstree.a gensquashfs_LDADD += libcompat.a $(LIBSELINUX_LIBS) $(LZO_LIBS) gensquashfs_LDADD += $(PTHREAD_LIBS) diff --git a/bin/gensquashfs/dirscan.c b/bin/gensquashfs/dirscan.c index dbc862c..bb6d2c3 100644 --- a/bin/gensquashfs/dirscan.c +++ b/bin/gensquashfs/dirscan.c @@ -1,201 +1,19 @@ /* SPDX-License-Identifier: GPL-3.0-or-later */ /* - * fstree_from_dir.c + * dirscan.c * * Copyright (C) 2019 David Oberhollenzer */ #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) +int fstree_from_dir(fstree_t *fs, const char *path, unsigned int flags) { - (void)fs; (void)path; (void)selinux_handle; (void)xwr; (void)flags; + (void)fs; (void)path; (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) { @@ -289,8 +107,7 @@ fail: return -1; } -int fstree_from_dir(fstree_t *fs, const char *path, void *selinux_handle, - sqfs_xattr_writer_t *xwr, unsigned int flags) +int fstree_from_dir(fstree_t *fs, const char *path, unsigned int flags) { struct stat sb; int fd; @@ -307,15 +124,6 @@ int fstree_from_dir(fstree_t *fs, const char *path, void *selinux_handle, 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; + return populate_dir(fd, fs, fs->root, sb.st_dev, flags); } #endif diff --git a/bin/gensquashfs/dirscan_xattr.c b/bin/gensquashfs/dirscan_xattr.c new file mode 100644 index 0000000..3995a19 --- /dev/null +++ b/bin/gensquashfs/dirscan_xattr.c @@ -0,0 +1,200 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * dirscan_xattr.c + * + * Copyright (C) 2019 David Oberhollenzer + */ +#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 + +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; +} + +int xattrs_from_dir(fstree_t *fs, const char *path, void *selinux_handle, + sqfs_xattr_writer_t *xwr, unsigned int flags) +{ + if (xwr == NULL) + return 0; + + if (selinux_handle == NULL && !(flags & DIR_SCAN_READ_XATTR)) + return 0; + + return xattr_xcan_dfs(path, selinux_handle, xwr, flags, fs->root); +} diff --git a/bin/gensquashfs/mkfs.c b/bin/gensquashfs/mkfs.c index b1542d1..87778d9 100644 --- a/bin/gensquashfs/mkfs.c +++ b/bin/gensquashfs/mkfs.c @@ -150,11 +150,6 @@ static int read_fstree(fstree_t *fs, options_t *opt, sqfs_xattr_writer_t *xwr, FILE *fp; int ret; - if (opt->infile == NULL) { - return fstree_from_dir(fs, opt->packdir, selinux_handle, - xwr, opt->dirscan_flags); - } - fp = fopen(opt->infile, "rb"); if (fp == NULL) { perror(opt->infile); @@ -203,23 +198,27 @@ int main(int argc, char **argv) goto out; } - if (read_fstree(&sqfs.fs, &opt, sqfs.xwr, sehnd)) { - if (sehnd != NULL) - selinux_close_context_file(sehnd); - goto out; + if (opt.infile == NULL) { + if (fstree_from_dir(&sqfs.fs, opt.packdir, opt.dirscan_flags)) + goto out; + } else { + if (read_fstree(&sqfs.fs, &opt, sqfs.xwr, sehnd)) + goto out; } if (opt.force_uid || opt.force_gid) override_owner_dfs(&opt, sqfs.fs.root); - if (sehnd != NULL) { - selinux_close_context_file(sehnd); - sehnd = NULL; - } - if (fstree_post_process(&sqfs.fs)) goto out; + if (opt.infile == NULL) { + if (xattrs_from_dir(&sqfs.fs, opt.packdir, sehnd, + sqfs.xwr, opt.dirscan_flags)) { + goto out; + } + } + if (pack_files(sqfs.data, &sqfs.fs, &opt)) goto out; @@ -229,5 +228,7 @@ int main(int argc, char **argv) status = EXIT_SUCCESS; out: sqfs_writer_cleanup(&sqfs, status); + if (sehnd != NULL) + selinux_close_context_file(sehnd); return status; } diff --git a/bin/gensquashfs/mkfs.h b/bin/gensquashfs/mkfs.h index 9a36d8c..6aa0c87 100644 --- a/bin/gensquashfs/mkfs.h +++ b/bin/gensquashfs/mkfs.h @@ -63,9 +63,10 @@ enum { void process_command_line(options_t *opt, int argc, char **argv); -int fstree_from_dir(fstree_t *fs, const char *path, void *selinux_handle, - sqfs_xattr_writer_t *xwr, unsigned int flags); +int fstree_from_dir(fstree_t *fs, const char *path, unsigned int flags); +int xattrs_from_dir(fstree_t *fs, const char *path, void *selinux_handle, + sqfs_xattr_writer_t *xwr, unsigned int flags); void *selinux_open_context_file(const char *filename); -- cgit v1.2.3