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Safe-links enforce on extract, fixes/refactorings
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Resolves #20
This commit is contained in:
Stephen Seo 2024-10-24 13:40:29 +09:00
parent 9d31798da6
commit fb1c24ba2c
3 changed files with 240 additions and 48 deletions
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266
src/archiver.c
View file

@ -806,6 +806,15 @@ int write_files_fn(void *data, void *ud) {
}
}
if (!abs_path && !rel_path) {
// No valid paths, set as invalid.
fprintf(stderr,
"WARNING: Could not get valid abs/rel path for symlink \"%s\" "
"(invalid symlink)!\n",
file_info->filename);
((uint8_t *)temp_to_write->buf)[1] |= 0x8;
}
// Store the 4 byte bit-flags for file.
simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write);
@ -2100,6 +2109,15 @@ int simple_archiver_write_v1(FILE *out_f, SDArchiverState *state,
}
}
if (!abs_path && !rel_path) {
// No valid paths, mark as invalid.
fprintf(stderr,
"WARNING: \"%s\" is an invalid symlink, will not store rel/abs "
"link paths!\n",
(const char *)node->data);
is_invalid = 1;
}
// Get symlink stats for permissions.
struct stat stat_buf;
memset(&stat_buf, 0, sizeof(struct stat));
@ -2842,6 +2860,18 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
// fprintf(stderr, "\"%s\" put in map\n", key);
}
}
__attribute__((cleanup(simple_archiver_list_free)))
SDArchiverLinkedList *links_list =
state && state->parsed && state->parsed->flags & 0x80
? NULL
: simple_archiver_list_init();
__attribute__((cleanup(simple_archiver_hash_map_free)))
SDArchiverHashMap *files_map =
state && state->parsed && state->parsed->flags & 0x80
? NULL
: simple_archiver_hash_map_init();
for (uint32_t idx = 0; idx < size; ++idx) {
if (is_sig_int_occurred) {
return SDAS_SIGINT;
@ -2972,6 +3002,28 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
cleanup_overwrite_filename_delete_simple(&to_overwrite_dest);
}
if (files_map && !skip && out_f_name) {
simple_archiver_hash_map_insert(
files_map, (void *)1, strdup((const char *)out_f_name),
strlen((const char *)out_f_name) + 1,
simple_archiver_helper_datastructure_cleanup_nop, NULL);
__attribute__((cleanup(
simple_archiver_helper_cleanup_c_string))) char *filename_copy =
strdup(out_f_name);
char *filename_dirname = dirname(filename_copy);
while (strcmp(filename_dirname, ".") != 0) {
if (!simple_archiver_hash_map_get(files_map, filename_dirname,
strlen(filename_dirname) + 1)) {
simple_archiver_hash_map_insert(
files_map, (void *)1, strdup(filename_dirname),
strlen(filename_dirname) + 1,
simple_archiver_helper_datastructure_cleanup_nop, NULL);
}
filename_dirname = dirname(filename_dirname);
}
}
#if SIMPLE_ARCHIVER_PLATFORM == SIMPLE_ARCHIVER_PLATFORM_COSMOPOLITAN || \
SIMPLE_ARCHIVER_PLATFORM == SIMPLE_ARCHIVER_PLATFORM_MAC || \
SIMPLE_ARCHIVER_PLATFORM == SIMPLE_ARCHIVER_PLATFORM_LINUX
@ -3450,19 +3502,19 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
if (ret == -1) {
if (retry_symlink) {
fprintf(stderr,
"WARNING: Failed to create symlink after removing "
" WARNING: Failed to create symlink after removing "
"existing symlink!\n");
goto V0_SYMLINK_CREATE_AFTER_0;
} else if (errno == EEXIST) {
if ((state->parsed->flags & 8) == 0) {
fprintf(
stderr,
"WARNING: Symlink already exists and "
" WARNING: Symlink already exists and "
"\"--overwrite-extract\" is not specified, skipping!\n");
goto V0_SYMLINK_CREATE_AFTER_0;
} else {
fprintf(stderr,
"NOTICE: Symlink already exists and "
" NOTICE: Symlink already exists and "
"\"--overwrite-extract\" specified, attempting to "
"overwrite...\n");
unlink(out_f_name);
@ -3473,16 +3525,20 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
return SDAS_FAILED_TO_EXTRACT_SYMLINK;
}
}
if (links_list) {
simple_archiver_list_add(links_list, strdup(out_f_name), NULL);
}
ret = fchmodat(AT_FDCWD, out_f_name, permissions,
AT_SYMLINK_NOFOLLOW);
if (ret == -1) {
if (errno == EOPNOTSUPP) {
fprintf(stderr,
"NOTICE: Setting permissions of symlink is not "
" NOTICE: Setting permissions of symlink is not "
"supported by FS/OS!\n");
} else {
fprintf(stderr,
"WARNING: Failed to set permissions of symlink (%d)!\n",
fprintf(
stderr,
" WARNING: Failed to set permissions of symlink (%d)!\n",
errno);
}
}
@ -3500,19 +3556,19 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
if (ret == -1) {
if (retry_symlink) {
fprintf(stderr,
"WARNING: Failed to create symlink after removing "
" WARNING: Failed to create symlink after removing "
"existing symlink!\n");
goto V0_SYMLINK_CREATE_AFTER_1;
} else if (errno == EEXIST) {
if ((state->parsed->flags & 8) == 0) {
fprintf(
stderr,
"WARNING: Symlink already exists and "
" WARNING: Symlink already exists and "
"\"--overwrite-extract\" is not specified, skipping!\n");
goto V0_SYMLINK_CREATE_AFTER_1;
} else {
fprintf(stderr,
"NOTICE: Symlink already exists and "
" NOTICE: Symlink already exists and "
"\"--overwrite-extract\" specified, attempting to "
"overwrite...\n");
unlink(out_f_name);
@ -3523,16 +3579,20 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
return SDAS_FAILED_TO_EXTRACT_SYMLINK;
}
}
if (links_list) {
simple_archiver_list_add(links_list, strdup(out_f_name), NULL);
}
ret = fchmodat(AT_FDCWD, out_f_name, permissions,
AT_SYMLINK_NOFOLLOW);
if (ret == -1) {
if (errno == EOPNOTSUPP) {
fprintf(stderr,
"NOTICE: Setting permissions of symlink is not "
" NOTICE: Setting permissions of symlink is not "
"supported by FS/OS!\n");
} else {
fprintf(stderr,
"WARNING: Failed to set permissions of symlink (%d)!\n",
fprintf(
stderr,
" WARNING: Failed to set permissions of symlink (%d)!\n",
errno);
}
}
@ -3548,16 +3608,20 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
if (ret == -1) {
return SDAS_FAILED_TO_EXTRACT_SYMLINK;
}
if (links_list) {
simple_archiver_list_add(links_list, strdup(out_f_name), NULL);
}
ret =
fchmodat(AT_FDCWD, out_f_name, permissions, AT_SYMLINK_NOFOLLOW);
if (ret == -1) {
if (errno == EOPNOTSUPP) {
fprintf(stderr,
"NOTICE: Setting permissions of symlink is not supported "
fprintf(
stderr,
" NOTICE: Setting permissions of symlink is not supported "
"by FS/OS!\n");
} else {
fprintf(stderr,
"WARNING: Failed to set permissions of symlink (%d)!\n",
" WARNING: Failed to set permissions of symlink (%d)!\n",
errno);
}
}
@ -3570,16 +3634,20 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
if (ret == -1) {
return SDAS_FAILED_TO_EXTRACT_SYMLINK;
}
if (links_list) {
simple_archiver_list_add(links_list, strdup(out_f_name), NULL);
}
ret =
fchmodat(AT_FDCWD, out_f_name, permissions, AT_SYMLINK_NOFOLLOW);
if (ret == -1) {
if (errno == EOPNOTSUPP) {
fprintf(stderr,
"NOTICE: Setting permissions of symlink is not supported "
fprintf(
stderr,
" NOTICE: Setting permissions of symlink is not supported "
"by FS/OS!\n");
} else {
fprintf(stderr,
"WARNING: Failed to set permissions of symlink (%d)!\n",
" WARNING: Failed to set permissions of symlink (%d)!\n",
errno);
}
}
@ -3587,12 +3655,16 @@ int simple_archiver_parse_archive_version_0(FILE *in_f, int_fast8_t do_extract,
} else {
fprintf(
stderr,
"WARNING: Symlink entry in archive has no paths to link to!\n");
" WARNING: Symlink entry in archive has no paths to link to!\n");
}
}
}
}
if (do_extract && links_list && files_map) {
simple_archiver_safe_links_enforce(links_list, files_map);
}
if (is_sig_int_occurred) {
return SDAS_SIGINT;
}
@ -3637,6 +3709,21 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
#endif
}
__attribute__((cleanup(simple_archiver_list_free)))
SDArchiverLinkedList *links_list =
state && state->parsed && state->parsed->flags & 0x80
? NULL
: simple_archiver_list_init();
__attribute__((cleanup(simple_archiver_hash_map_free)))
SDArchiverHashMap *files_map =
state && state->parsed && state->parsed->flags & 0x80
? NULL
: simple_archiver_hash_map_init();
__attribute__((
cleanup(simple_archiver_helper_cleanup_c_string))) char *cwd_realpath =
realpath(".", NULL);
const int_fast8_t is_compressed = (buf[0] & 1) ? 1 : 0;
__attribute__((cleanup(
@ -3704,9 +3791,7 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
const uint_fast8_t is_invalid = (buf[1] & 4) ? 1 : 0;
if (is_invalid) {
fprintf(stderr,
" WARNING: This symlink entry was marked invalid (not a safe "
"link)!\n");
fprintf(stderr, " WARNING: This symlink entry was marked invalid!\n");
}
#if SIMPLE_ARCHIVER_PLATFORM == SIMPLE_ARCHIVER_PLATFORM_COSMOPOLITAN || \
@ -3789,21 +3874,22 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
ret = symlink(path, link_name);
if (ret == -1) {
if (link_create_retry) {
fprintf(stderr,
"WARNING: Failed to create symlink after removing existing "
fprintf(
stderr,
" WARNING: Failed to create symlink after removing existing "
"symlink!\n");
goto V1_SYMLINK_CREATE_AFTER_0;
} else if (errno == EEXIST) {
if ((state->parsed->flags & 8) == 0) {
fprintf(stderr,
"WARNING: Symlink already exists and "
" WARNING: Symlink already exists and "
"\"--overwrite-extract\" is not specified, skipping!\n");
goto V1_SYMLINK_CREATE_AFTER_0;
} else {
fprintf(
stderr,
"NOTICE: Symlink already exists and \"--overwrite-extract\" "
"specified, attempting to overwrite...\n");
fprintf(stderr,
" NOTICE: Symlink already exists and "
"\"--overwrite-extract\" specified, attempting to "
"overwrite...\n");
unlink(link_name);
link_create_retry = 1;
goto V1_SYMLINK_CREATE_RETRY_0;
@ -3815,11 +3901,11 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
if (ret == -1) {
if (errno == EOPNOTSUPP) {
fprintf(stderr,
"NOTICE: Setting permissions of symlink is not supported "
" NOTICE: Setting permissions of symlink is not supported "
"by FS/OS!\n");
} else {
fprintf(stderr,
"WARNING: Failed to set permissions of symlink (%d)!\n",
" WARNING: Failed to set permissions of symlink (%d)!\n",
errno);
}
}
@ -3828,7 +3914,7 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
V1_SYMLINK_CREATE_AFTER_0:
link_create_retry = 1;
#endif
} else {
} else if (!do_extract) {
fprintf(stderr, " Abs path: %s\n", path);
}
} else if (!do_extract) {
@ -3861,21 +3947,22 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
ret = symlink(path, link_name);
if (ret == -1) {
if (link_create_retry) {
fprintf(stderr,
"WARNING: Failed to create symlink after removing existing "
fprintf(
stderr,
" WARNING: Failed to create symlink after removing existing "
"symlink!\n");
goto V1_SYMLINK_CREATE_AFTER_1;
} else if (errno == EEXIST) {
if ((state->parsed->flags & 8) == 0) {
fprintf(stderr,
"WARNING: Symlink already exists and "
" WARNING: Symlink already exists and "
"\"--overwrite-extract\" is not specified, skipping!\n");
goto V1_SYMLINK_CREATE_AFTER_1;
} else {
fprintf(
stderr,
"NOTICE: Symlink already exists and \"--overwrite-extract\" "
"specified, attempting to overwrite...\n");
fprintf(stderr,
" NOTICE: Symlink already exists and "
"\"--overwrite-extract\" specified, attempting to "
"overwrite...\n");
unlink(link_name);
link_create_retry = 1;
goto V1_SYMLINK_CREATE_RETRY_1;
@ -3887,11 +3974,11 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
if (ret == -1) {
if (errno == EOPNOTSUPP) {
fprintf(stderr,
"NOTICE: Setting permissions of symlink is not supported "
" NOTICE: Setting permissions of symlink is not supported "
"by FS/OS!\n");
} else {
fprintf(stderr,
"WARNING: Failed to set permissions of symlink (%d)!\n",
" WARNING: Failed to set permissions of symlink (%d)!\n",
errno);
}
}
@ -3900,7 +3987,7 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
V1_SYMLINK_CREATE_AFTER_1:
link_create_retry = 1;
#endif
} else {
} else if (!do_extract) {
fprintf(stderr, " Rel path: %s\n", path);
}
} else if (!do_extract) {
@ -3911,6 +3998,9 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
!skip_due_to_invalid) {
fprintf(stderr, " WARNING: Symlink \"%s\" was not created!\n",
link_name);
} else if (do_extract && link_extracted && !skip_due_to_map &&
!skip_due_to_invalid && links_list) {
simple_archiver_list_add(links_list, strdup(link_name), NULL);
}
}
@ -4011,6 +4101,28 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
simple_archiver_helper_64_bit_be(&u64);
file_info->file_size = u64;
if (files_map) {
simple_archiver_hash_map_insert(
files_map, (void *)1, strdup(file_info->filename),
strlen(file_info->filename) + 1,
simple_archiver_helper_datastructure_cleanup_nop, NULL);
__attribute__((cleanup(
simple_archiver_helper_cleanup_c_string))) char *filename_copy =
strdup(file_info->filename);
char *filename_dirname = dirname(filename_copy);
while (strcmp(filename_dirname, ".") != 0) {
if (!simple_archiver_hash_map_get(files_map, filename_dirname,
strlen(filename_dirname) + 1)) {
simple_archiver_hash_map_insert(
files_map, (void *)1, strdup(filename_dirname),
strlen(filename_dirname) + 1,
simple_archiver_helper_datastructure_cleanup_nop, NULL);
}
filename_dirname = dirname(filename_dirname);
}
}
simple_archiver_list_add(file_info_list, file_info,
free_internal_file_info);
file_info = NULL;
@ -4340,6 +4452,10 @@ int simple_archiver_parse_archive_version_1(FILE *in_f, int_fast8_t do_extract,
}
}
if (do_extract && links_list && files_map) {
simple_archiver_safe_links_enforce(links_list, files_map);
}
return SDAS_SUCCESS;
}
@ -4523,3 +4639,69 @@ int simple_archiver_validate_file_path(const char *filepath) {
return 0;
}
void simple_archiver_safe_links_enforce(SDArchiverLinkedList *links_list,
SDArchiverHashMap *files_map) {
uint_fast8_t need_to_print_note = 1;
// safe-links: Check that every link maps to a file in the files_map.
__attribute__((
cleanup(simple_archiver_helper_cleanup_c_string))) char *path_to_cwd =
realpath(".", NULL);
// Ensure path_to_cwd ends with '/'.
uint32_t idx = 0;
while (path_to_cwd[idx] != 0) {
++idx;
}
if (path_to_cwd[idx - 1] != '/') {
char *temp = malloc(idx + 2);
memcpy(temp, path_to_cwd, idx);
temp[idx] = '/';
temp[idx + 1] = 0;
free(path_to_cwd);
path_to_cwd = temp;
}
// Check every link to make sure it points to an existing file.
SDArchiverLLNode *links_node = links_list->head;
while (links_node->next != links_list->tail) {
links_node = links_node->next;
__attribute__((
cleanup(simple_archiver_helper_cleanup_c_string))) char *link_realpath =
realpath(links_node->data, NULL);
if (link_realpath) {
// Get local path.
__attribute__((cleanup(
simple_archiver_helper_cleanup_c_string))) char *link_localpath =
simple_archiver_filenames_to_relative_path(path_to_cwd,
link_realpath);
if (!simple_archiver_hash_map_get(files_map, link_localpath,
strlen(link_localpath) + 1)) {
// Invalid symlink.
fprintf(stderr,
"Symlink \"%s\" is invalid (not pointing to archived file), "
"removing...\n",
(const char *)links_node->data);
unlink(links_node->data);
if (need_to_print_note) {
fprintf(stderr,
"NOTE: Disable this behavior with \"--no-safe-links\" if "
"needed.\n");
need_to_print_note = 0;
}
}
} else {
// Invalid symlink.
fprintf(stderr,
"Symlink \"%s\" is invalid (failed to resolve), removing...\n",
(const char *)links_node->data);
unlink(links_node->data);
if (need_to_print_note) {
fprintf(stderr,
"NOTE: Disable this behavior with \"--no-safe-links\" if "
"needed.\n");
need_to_print_note = 0;
}
}
}
}

5
src/archiver.h
View file

@ -109,4 +109,9 @@ char *simple_archiver_file_abs_path(const char *filename);
/// Returns 5 if "filepath" is NULL.
int simple_archiver_validate_file_path(const char *filepath);
/// Removes links from "links_list" in cwd if it is not valid or does not point
/// to a file in "files_map".
void simple_archiver_safe_links_enforce(SDArchiverLinkedList *links_list,
SDArchiverHashMap *files_map);
#endif

5
src/test.c
View file

@ -256,6 +256,11 @@ int main(void) {
CHECK_STREQ(rel_path, "../other/dir/");
simple_archiver_helper_cleanup_c_string(&rel_path);
rel_path = simple_archiver_filenames_to_relative_path(
"/one/two/three/", "/one/two/three/four");
CHECK_STREQ(rel_path, "four");
simple_archiver_helper_cleanup_c_string(&rel_path);
CHECK_FALSE(simple_archiver_validate_file_path("Local/Path"));
CHECK_TRUE(simple_archiver_validate_file_path("/Abs/Path"));
CHECK_TRUE(simple_archiver_validate_file_path("Local/../../not/really"));