| /* SPDX-License-Identifier: LGPL-2.1-or-later */ | |
| #include <sys/prctl.h> | |
| #include "alloc-util.h" | |
| #include "btrfs-util.h" | |
| #include "capability-util.h" | |
| #include "copy.h" | |
| #include "dirent-util.h" | |
| #include "escape.h" | |
| #include "fd-util.h" | |
| #include "io-util.h" | |
| #include "path-util.h" | |
| #include "process-util.h" | |
| #include "pull-common.h" | |
| #include "pull-job.h" | |
| #include "rlimit-util.h" | |
| #include "rm-rf.h" | |
| #include "signal-util.h" | |
| #include "siphash24.h" | |
| #include "string-util.h" | |
| #include "strv.h" | |
| #include "util.h" | |
| #include "web-util.h" | |
| #define FILENAME_ESCAPE "/.#\"\'" | |
| #define HASH_URL_THRESHOLD_LENGTH (_POSIX_PATH_MAX - 16) | |
| int pull_find_old_etags( | |
| const char *url, | |
| const char *image_root, | |
| int dt, | |
| const char *prefix, | |
| const char *suffix, | |
| char ***etags) { | |
| _cleanup_free_ char *escaped_url = NULL; | |
| _cleanup_closedir_ DIR *d = NULL; | |
| _cleanup_strv_free_ char **l = NULL; | |
| struct dirent *de; | |
| int r; | |
| assert(url); | |
| assert(etags); | |
| if (!image_root) | |
| image_root = "/var/lib/machines"; | |
| escaped_url = xescape(url, FILENAME_ESCAPE); | |
| if (!escaped_url) | |
| return -ENOMEM; | |
| d = opendir(image_root); | |
| if (!d) { | |
| if (errno == ENOENT) { | |
| *etags = NULL; | |
| return 0; | |
| } | |
| return -errno; | |
| } | |
| FOREACH_DIRENT_ALL(de, d, return -errno) { | |
| _cleanup_free_ char *u = NULL; | |
| const char *a, *b; | |
| if (de->d_type != DT_UNKNOWN && | |
| de->d_type != dt) | |
| continue; | |
| if (prefix) { | |
| a = startswith(de->d_name, prefix); | |
| if (!a) | |
| continue; | |
| } else | |
| a = de->d_name; | |
| a = startswith(a, escaped_url); | |
| if (!a) | |
| continue; | |
| a = startswith(a, "."); | |
| if (!a) | |
| continue; | |
| if (suffix) { | |
| b = endswith(de->d_name, suffix); | |
| if (!b) | |
| continue; | |
| } else | |
| b = strchr(de->d_name, 0); | |
| if (a >= b) | |
| continue; | |
| r = cunescape_length(a, b - a, 0, &u); | |
| if (r < 0) | |
| return r; | |
| if (!http_etag_is_valid(u)) | |
| continue; | |
| r = strv_consume(&l, TAKE_PTR(u)); | |
| if (r < 0) | |
| return r; | |
| } | |
| *etags = TAKE_PTR(l); | |
| return 0; | |
| } | |
| int pull_make_local_copy(const char *final, const char *image_root, const char *local, PullFlags flags) { | |
| const char *p; | |
| int r; | |
| assert(final); | |
| assert(local); | |
| if (!image_root) | |
| image_root = "/var/lib/machines"; | |
| p = prefix_roota(image_root, local); | |
| if (FLAGS_SET(flags, PULL_FORCE)) | |
| (void) rm_rf(p, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME); | |
| r = btrfs_subvol_snapshot(final, p, | |
| BTRFS_SNAPSHOT_QUOTA| | |
| BTRFS_SNAPSHOT_FALLBACK_COPY| | |
| BTRFS_SNAPSHOT_FALLBACK_DIRECTORY| | |
| BTRFS_SNAPSHOT_RECURSIVE); | |
| if (r < 0) | |
| return log_error_errno(r, "Failed to create local image: %m"); | |
| log_info("Created new local image '%s'.", local); | |
| return 0; | |
| } | |
| static int hash_url(const char *url, char **ret) { | |
| uint64_t h; | |
| static const sd_id128_t k = SD_ID128_ARRAY(df,89,16,87,01,cc,42,30,98,ab,4a,19,a6,a5,63,4f); | |
| assert(url); | |
| h = siphash24(url, strlen(url), k.bytes); | |
| if (asprintf(ret, "%"PRIx64, h) < 0) | |
| return -ENOMEM; | |
| return 0; | |
| } | |
| int pull_make_path(const char *url, const char *etag, const char *image_root, const char *prefix, const char *suffix, char **ret) { | |
| _cleanup_free_ char *escaped_url = NULL, *escaped_etag = NULL; | |
| char *path; | |
| assert(url); | |
| assert(ret); | |
| if (!image_root) | |
| image_root = "/var/lib/machines"; | |
| escaped_url = xescape(url, FILENAME_ESCAPE); | |
| if (!escaped_url) | |
| return -ENOMEM; | |
| if (etag) { | |
| escaped_etag = xescape(etag, FILENAME_ESCAPE); | |
| if (!escaped_etag) | |
| return -ENOMEM; | |
| } | |
| path = strjoin(image_root, "/", strempty(prefix), escaped_url, escaped_etag ? "." : "", | |
| strempty(escaped_etag), strempty(suffix)); | |
| if (!path) | |
| return -ENOMEM; | |
| /* URLs might make the path longer than the maximum allowed length for a file name. | |
| * When that happens, a URL hash is used instead. Paths returned by this function | |
| * can be later used with tempfn_random() which adds 16 bytes to the resulting name. */ | |
| if (strlen(path) >= HASH_URL_THRESHOLD_LENGTH) { | |
| _cleanup_free_ char *hash = NULL; | |
| int r; | |
| free(path); | |
| r = hash_url(url, &hash); | |
| if (r < 0) | |
| return r; | |
| path = strjoin(image_root, "/", strempty(prefix), hash, escaped_etag ? "." : "", | |
| strempty(escaped_etag), strempty(suffix)); | |
| if (!path) | |
| return -ENOMEM; | |
| } | |
| *ret = path; | |
| return 0; | |
| } | |
| int pull_make_auxiliary_job( | |
| PullJob **ret, | |
| const char *url, | |
| int (*strip_suffixes)(const char *name, char **ret), | |
| const char *suffix, | |
| CurlGlue *glue, | |
| PullJobFinished on_finished, | |
| void *userdata) { | |
| _cleanup_free_ char *last_component = NULL, *ll = NULL, *auxiliary_url = NULL; | |
| _cleanup_(pull_job_unrefp) PullJob *job = NULL; | |
| const char *q; | |
| int r; | |
| assert(ret); | |
| assert(url); | |
| assert(strip_suffixes); | |
| assert(glue); | |
| r = import_url_last_component(url, &last_component); | |
| if (r < 0) | |
| return r; | |
| r = strip_suffixes(last_component, &ll); | |
| if (r < 0) | |
| return r; | |
| q = strjoina(ll, suffix); | |
| r = import_url_change_last_component(url, q, &auxiliary_url); | |
| if (r < 0) | |
| return r; | |
| r = pull_job_new(&job, auxiliary_url, glue, userdata); | |
| if (r < 0) | |
| return r; | |
| job->on_finished = on_finished; | |
| job->compressed_max = job->uncompressed_max = 1ULL * 1024ULL * 1024ULL; | |
| *ret = TAKE_PTR(job); | |
| return 0; | |
| } | |
| int pull_make_verification_jobs( | |
| PullJob **ret_checksum_job, | |
| PullJob **ret_signature_job, | |
| ImportVerify verify, | |
| const char *url, | |
| CurlGlue *glue, | |
| PullJobFinished on_finished, | |
| void *userdata) { | |
| _cleanup_(pull_job_unrefp) PullJob *checksum_job = NULL, *signature_job = NULL; | |
| int r; | |
| assert(ret_checksum_job); | |
| assert(ret_signature_job); | |
| assert(verify >= 0); | |
| assert(verify < _IMPORT_VERIFY_MAX); | |
| assert(url); | |
| assert(glue); | |
| if (verify != IMPORT_VERIFY_NO) { | |
| _cleanup_free_ char *checksum_url = NULL, *fn = NULL; | |
| const char *chksums = NULL; | |
| /* Queue jobs for the checksum file for the image. */ | |
| r = import_url_last_component(url, &fn); | |
| if (r < 0) | |
| return r; | |
| chksums = strjoina(fn, ".sha256"); | |
| r = import_url_change_last_component(url, chksums, &checksum_url); | |
| if (r < 0) | |
| return r; | |
| r = pull_job_new(&checksum_job, checksum_url, glue, userdata); | |
| if (r < 0) | |
| return r; | |
| checksum_job->on_finished = on_finished; | |
| checksum_job->uncompressed_max = checksum_job->compressed_max = 1ULL * 1024ULL * 1024ULL; | |
| } | |
| if (verify == IMPORT_VERIFY_SIGNATURE) { | |
| _cleanup_free_ char *signature_url = NULL; | |
| /* Queue job for the SHA256SUMS.gpg file for the image. */ | |
| r = import_url_change_last_component(url, "SHA256SUMS.gpg", &signature_url); | |
| if (r < 0) | |
| return r; | |
| r = pull_job_new(&signature_job, signature_url, glue, userdata); | |
| if (r < 0) | |
| return r; | |
| signature_job->on_finished = on_finished; | |
| signature_job->uncompressed_max = signature_job->compressed_max = 1ULL * 1024ULL * 1024ULL; | |
| } | |
| *ret_checksum_job = TAKE_PTR(checksum_job); | |
| *ret_signature_job = TAKE_PTR(signature_job); | |
| return 0; | |
| } | |
| static int verify_one(PullJob *checksum_job, PullJob *job) { | |
| _cleanup_free_ char *fn = NULL; | |
| const char *line, *p; | |
| int r; | |
| assert(checksum_job); | |
| if (!job) | |
| return 0; | |
| assert(IN_SET(job->state, PULL_JOB_DONE, PULL_JOB_FAILED)); | |
| /* Don't verify the checksum if we didn't actually successfully download something new */ | |
| if (job->state != PULL_JOB_DONE) | |
| return 0; | |
| if (job->error != 0) | |
| return 0; | |
| if (job->etag_exists) | |
| return 0; | |
| assert(job->calc_checksum); | |
| assert(job->checksum); | |
| r = import_url_last_component(job->url, &fn); | |
| if (r < 0) | |
| return log_oom(); | |
| if (!filename_is_valid(fn)) | |
| return log_error_errno(SYNTHETIC_ERRNO(EBADMSG), | |
| "Cannot verify checksum, could not determine server-side file name."); | |
| line = strjoina(job->checksum, " *", fn, "\n"); | |
| p = memmem(checksum_job->payload, | |
| checksum_job->payload_size, | |
| line, | |
| strlen(line)); | |
| if (!p) { | |
| line = strjoina(job->checksum, " ", fn, "\n"); | |
| p = memmem(checksum_job->payload, | |
| checksum_job->payload_size, | |
| line, | |
| strlen(line)); | |
| } | |
| if (!p || (p != (char*) checksum_job->payload && p[-1] != '\n')) | |
| return log_error_errno(SYNTHETIC_ERRNO(EBADMSG), | |
| "DOWNLOAD INVALID: Checksum of %s file did not checkout, file has been tampered with.", fn); | |
| log_info("SHA256 checksum of %s is valid.", job->url); | |
| return 1; | |
| } | |
| static int verify_gpg( | |
| const void *payload, size_t payload_size, | |
| const void *signature, size_t signature_size) { | |
| _cleanup_close_pair_ int gpg_pipe[2] = { -1, -1 }; | |
| char sig_file_path[] = "/tmp/sigXXXXXX", gpg_home[] = "/tmp/gpghomeXXXXXX"; | |
| _cleanup_(sigkill_waitp) pid_t pid = 0; | |
| bool gpg_home_created = false; | |
| int r; | |
| assert(payload || payload_size == 0); | |
| assert(signature || signature_size == 0); | |
| r = pipe2(gpg_pipe, O_CLOEXEC); | |
| if (r < 0) | |
| return log_error_errno(errno, "Failed to create pipe for gpg: %m"); | |
| if (signature_size > 0) { | |
| _cleanup_close_ int sig_file = -1; | |
| sig_file = mkostemp(sig_file_path, O_RDWR); | |
| if (sig_file < 0) | |
| return log_error_errno(errno, "Failed to create temporary file: %m"); | |
| r = loop_write(sig_file, signature, signature_size, false); | |
| if (r < 0) { | |
| log_error_errno(r, "Failed to write to temporary file: %m"); | |
| goto finish; | |
| } | |
| } | |
| if (!mkdtemp(gpg_home)) { | |
| r = log_error_errno(errno, "Failed to create temporary home for gpg: %m"); | |
| goto finish; | |
| } | |
| gpg_home_created = true; | |
| r = safe_fork("(gpg)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_LOG, &pid); | |
| if (r < 0) | |
| return r; | |
| if (r == 0) { | |
| const char *cmd[] = { | |
| "gpg", | |
| "--no-options", | |
| "--no-default-keyring", | |
| "--no-auto-key-locate", | |
| "--no-auto-check-trustdb", | |
| "--batch", | |
| "--trust-model=always", | |
| NULL, /* --homedir= */ | |
| NULL, /* --keyring= */ | |
| NULL, /* --verify */ | |
| NULL, /* signature file */ | |
| NULL, /* dash */ | |
| NULL /* trailing NULL */ | |
| }; | |
| size_t k = ELEMENTSOF(cmd) - 6; | |
| /* Child */ | |
| gpg_pipe[1] = safe_close(gpg_pipe[1]); | |
| r = rearrange_stdio(gpg_pipe[0], -1, STDERR_FILENO); | |
| if (r < 0) { | |
| log_error_errno(r, "Failed to rearrange stdin/stdout: %m"); | |
| _exit(EXIT_FAILURE); | |
| } | |
| (void) rlimit_nofile_safe(); | |
| cmd[k++] = strjoina("--homedir=", gpg_home); | |
| /* We add the user keyring only to the command line arguments, if it's around since gpg fails | |
| * otherwise. */ | |
| if (access(USER_KEYRING_PATH, F_OK) >= 0) | |
| cmd[k++] = "--keyring=" USER_KEYRING_PATH; | |
| else | |
| cmd[k++] = "--keyring=" VENDOR_KEYRING_PATH; | |
| cmd[k++] = "--verify"; | |
| if (signature) { | |
| cmd[k++] = sig_file_path; | |
| cmd[k++] = "-"; | |
| cmd[k++] = NULL; | |
| } | |
| execvp("gpg2", (char * const *) cmd); | |
| execvp("gpg", (char * const *) cmd); | |
| log_error_errno(errno, "Failed to execute gpg: %m"); | |
| _exit(EXIT_FAILURE); | |
| } | |
| gpg_pipe[0] = safe_close(gpg_pipe[0]); | |
| r = loop_write(gpg_pipe[1], payload, payload_size, false); | |
| if (r < 0) { | |
| log_error_errno(r, "Failed to write to pipe: %m"); | |
| goto finish; | |
| } | |
| gpg_pipe[1] = safe_close(gpg_pipe[1]); | |
| r = wait_for_terminate_and_check("gpg", pid, WAIT_LOG_ABNORMAL); | |
| pid = 0; | |
| if (r < 0) | |
| goto finish; | |
| if (r != EXIT_SUCCESS) { | |
| log_error("DOWNLOAD INVALID: Signature verification failed."); | |
| r = -EBADMSG; | |
| } else { | |
| log_info("Signature verification succeeded."); | |
| r = 0; | |
| } | |
| finish: | |
| if (signature_size > 0) | |
| (void) unlink(sig_file_path); | |
| if (gpg_home_created) | |
| (void) rm_rf(gpg_home, REMOVE_ROOT|REMOVE_PHYSICAL); | |
| return r; | |
| } | |
| int pull_verify(ImportVerify verify, | |
| PullJob *main_job, | |
| PullJob *checksum_job, | |
| PullJob *signature_job, | |
| PullJob *settings_job, | |
| PullJob *roothash_job, | |
| PullJob *roothash_signature_job, | |
| PullJob *verity_job) { | |
| VerificationStyle style; | |
| PullJob *j; | |
| int r; | |
| assert(main_job); | |
| assert(main_job->state == PULL_JOB_DONE); | |
| if (verify == IMPORT_VERIFY_NO) | |
| return 0; | |
| assert(main_job->calc_checksum); | |
| assert(main_job->checksum); | |
| assert(checksum_job); | |
| assert(checksum_job->state == PULL_JOB_DONE); | |
| if (!checksum_job->payload || checksum_job->payload_size <= 0) | |
| return log_error_errno(SYNTHETIC_ERRNO(EBADMSG), | |
| "Checksum is empty, cannot verify."); | |
| FOREACH_POINTER(j, main_job, settings_job, roothash_job, roothash_signature_job, verity_job) { | |
| r = verify_one(checksum_job, j); | |
| if (r < 0) | |
| return r; | |
| } | |
| if (verify == IMPORT_VERIFY_CHECKSUM) | |
| return 0; | |
| r = verification_style_from_url(checksum_job->url, &style); | |
| if (r < 0) | |
| return log_error_errno(r, "Failed to determine verification style from URL '%s': %m", checksum_job->url); | |
| if (style == VERIFICATION_PER_DIRECTORY) { | |
| assert(signature_job); | |
| assert(signature_job->state == PULL_JOB_DONE); | |
| if (!signature_job->payload || signature_job->payload_size <= 0) | |
| return log_error_errno(SYNTHETIC_ERRNO(EBADMSG), | |
| "Signature is empty, cannot verify."); | |
| return verify_gpg(checksum_job->payload, checksum_job->payload_size, signature_job->payload, signature_job->payload_size); | |
| } else | |
| return verify_gpg(checksum_job->payload, checksum_job->payload_size, NULL, 0); | |
| } | |
| int verification_style_from_url(const char *url, VerificationStyle *ret) { | |
| _cleanup_free_ char *last = NULL; | |
| int r; | |
| assert(url); | |
| assert(ret); | |
| /* Determines which kind of verification style is appropriate for this url */ | |
| r = import_url_last_component(url, &last); | |
| if (r < 0) | |
| return r; | |
| if (streq(last, "SHA256SUMS")) { | |
| *ret = VERIFICATION_PER_DIRECTORY; | |
| return 0; | |
| } | |
| if (endswith(last, ".sha256")) { | |
| *ret = VERIFICATION_PER_FILE; | |
| return 0; | |
| } | |
| return -EINVAL; | |
| } | |
| int pull_job_restart_with_sha256sum(PullJob *j, char **ret) { | |
| VerificationStyle style; | |
| int r; | |
| assert(j); | |
| /* Generic implementation of a PullJobNotFound handler, that restarts the job requesting SHA256SUMS */ | |
| r = verification_style_from_url(j->url, &style); | |
| if (r < 0) | |
| return log_error_errno(r, "Failed to determine verification style of URL '%s': %m", j->url); | |
| if (style == VERIFICATION_PER_DIRECTORY) /* Nothing to do anymore */ | |
| return 0; | |
| assert(style == VERIFICATION_PER_FILE); /* This must have been .sha256 style URL before */ | |
| log_debug("Got 404 for %s, now trying to get SHA256SUMS instead.", j->url); | |
| r = import_url_change_last_component(j->url, "SHA256SUMS", ret); | |
| if (r < 0) | |
| return log_error_errno(r, "Failed to replace SHA256SUMS suffix: %m"); | |
| return 1; | |
| } |