[thirdparty/systemd.git] / src / import / pull-common.c

/* 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 *roothash_job,
                PullJob *settings_job,
                PullJob *checksum_job,
                PullJob *signature_job) {

        VerificationStyle style;
        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.");

        r = verify_one(checksum_job, main_job);
        if (r < 0)
                return r;

        r = verify_one(checksum_job, roothash_job);
        if (r < 0)
                return r;

        r = verify_one(checksum_job, settings_job);
        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;
}
Commit	Line	Data
db9ecf05	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
56ebfaf1	2
98c38001 LP	3	#include <sys/prctl.h>
98c38001 LP	4
b5efdb8a	5	#include "alloc-util.h"
56ebfaf1	6	#include "btrfs-util.h"
430f0182	7	#include "capability-util.h"
4f5dd394	8	#include "copy.h"
a0956174	9	#include "dirent-util.h"
4f5dd394	10	#include "escape.h"
3ffd4af2	11	#include "fd-util.h"
c004493c	12	#include "io-util.h"
bb15fafe	13	#include "path-util.h"
0b452006	14	#include "process-util.h"
3ffd4af2	15	#include "pull-common.h"
4f5dd394	16	#include "pull-job.h"
595225af	17	#include "rlimit-util.h"
4f5dd394	18	#include "rm-rf.h"
24882e06	19	#include "signal-util.h"
9818005d	20	#include "siphash24.h"
07630cea	21	#include "string-util.h"
4f5dd394 LP	22	#include "strv.h"
4f5dd394 LP	23	#include "util.h"
49cf4170	24	#include "web-util.h"
56ebfaf1 LP	25
56ebfaf1 LP	26	#define FILENAME_ESCAPE "/.#\"\'"
9818005d	27	#define HASH_URL_THRESHOLD_LENGTH (_POSIX_PATH_MAX - 16)
56ebfaf1	28
9854730b LP	29	int pull_find_old_etags(
	30	const char *url,
	31	const char *image_root,
	32	int dt,
	33	const char *prefix,
	34	const char *suffix,
	35	char ***etags) {
	36
56ebfaf1 LP	37	_cleanup_free_ char *escaped_url = NULL;
	38	_cleanup_closedir_ DIR *d = NULL;
	39	_cleanup_strv_free_ char **l = NULL;
	40	struct dirent *de;
	41	int r;
	42
	43	assert(url);
	44	assert(etags);
	45
	46	if (!image_root)
	47	image_root = "/var/lib/machines";
	48
	49	escaped_url = xescape(url, FILENAME_ESCAPE);
	50	if (!escaped_url)
	51	return -ENOMEM;
	52
	53	d = opendir(image_root);
	54	if (!d) {
	55	if (errno == ENOENT) {
	56	*etags = NULL;
	57	return 0;
	58	}
	59
	60	return -errno;
	61	}
	62
	63	FOREACH_DIRENT_ALL(de, d, return -errno) {
6abdec98	64	_cleanup_free_ char *u = NULL;
56ebfaf1	65	const char a, b;
56ebfaf1 LP	66
	67	if (de->d_type != DT_UNKNOWN &&
	68	de->d_type != dt)
	69	continue;
	70
	71	if (prefix) {
	72	a = startswith(de->d_name, prefix);
	73	if (!a)
	74	continue;
	75	} else
	76	a = de->d_name;
	77
	78	a = startswith(a, escaped_url);
	79	if (!a)
	80	continue;
	81
	82	a = startswith(a, ".");
	83	if (!a)
	84	continue;
	85
	86	if (suffix) {
	87	b = endswith(de->d_name, suffix);
	88	if (!b)
	89	continue;
	90	} else
	91	b = strchr(de->d_name, 0);
	92
	93	if (a >= b)
	94	continue;
	95
527b7a42 LP	96	r = cunescape_length(a, b - a, 0, &u);
	97	if (r < 0)
	98	return r;
56ebfaf1	99
6abdec98	100	if (!http_etag_is_valid(u))
56ebfaf1	101	continue;
56ebfaf1	102
6abdec98	103	r = strv_consume(&l, TAKE_PTR(u));
56ebfaf1 LP	104	if (r < 0)
	105	return r;
	106	}
	107
ae2a15bc	108	*etags = TAKE_PTR(l);
56ebfaf1 LP	109
	110	return 0;
	111	}
	112
133b34f6	113	int pull_make_local_copy(const char final, const char image_root, const char *local, PullFlags flags) {
56ebfaf1 LP	114	const char *p;
	115	int r;
	116
	117	assert(final);
	118	assert(local);
	119
	120	if (!image_root)
	121	image_root = "/var/lib/machines";
	122
270384b2	123	p = prefix_roota(image_root, local);
56ebfaf1	124
133b34f6	125	if (FLAGS_SET(flags, PULL_FORCE))
d9e2daaf	126	(void) rm_rf(p, REMOVE_ROOT\|REMOVE_PHYSICAL\|REMOVE_SUBVOLUME);
56ebfaf1	127
17cbb288 LP	128	r = btrfs_subvol_snapshot(final, p,
	129	BTRFS_SNAPSHOT_QUOTA\|
	130	BTRFS_SNAPSHOT_FALLBACK_COPY\|
	131	BTRFS_SNAPSHOT_FALLBACK_DIRECTORY\|
	132	BTRFS_SNAPSHOT_RECURSIVE);
	133	if (r < 0)
56ebfaf1 LP	134	return log_error_errno(r, "Failed to create local image: %m");
	135
	136	log_info("Created new local image '%s'.", local);
	137
	138	return 0;
	139	}
	140
9818005d JS	141	static int hash_url(const char url, char *ret) {
	142	uint64_t h;
	143	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);
	144
	145	assert(url);
	146
933f9cae	147	h = siphash24(url, strlen(url), k.bytes);
9818005d JS	148	if (asprintf(ret, "%"PRIx64, h) < 0)
	149	return -ENOMEM;
	150
	151	return 0;
	152	}
	153
dc2c282b	154	int pull_make_path(const char url, const char etag, const char image_root, const char prefix, const char suffix, char *ret) {
9818005d	155	_cleanup_free_ char escaped_url = NULL, escaped_etag = NULL;
56ebfaf1 LP	156	char *path;
	157
	158	assert(url);
	159	assert(ret);
	160
	161	if (!image_root)
	162	image_root = "/var/lib/machines";
	163
	164	escaped_url = xescape(url, FILENAME_ESCAPE);
	165	if (!escaped_url)
	166	return -ENOMEM;
	167
	168	if (etag) {
56ebfaf1 LP	169	escaped_etag = xescape(etag, FILENAME_ESCAPE);
	170	if (!escaped_etag)
	171	return -ENOMEM;
9818005d	172	}
56ebfaf1	173
9818005d	174	path = strjoin(image_root, "/", strempty(prefix), escaped_url, escaped_etag ? "." : "",
4600a396	175	strempty(escaped_etag), strempty(suffix));
56ebfaf1 LP	176	if (!path)
	177	return -ENOMEM;
	178
9818005d JS	179	/* URLs might make the path longer than the maximum allowed length for a file name.
	180	* When that happens, a URL hash is used instead. Paths returned by this function
	181	* can be later used with tempfn_random() which adds 16 bytes to the resulting name. */
	182	if (strlen(path) >= HASH_URL_THRESHOLD_LENGTH) {
	183	_cleanup_free_ char *hash = NULL;
	184	int r;
	185
	186	free(path);
	187
	188	r = hash_url(url, &hash);
	189	if (r < 0)
	190	return r;
	191
	192	path = strjoin(image_root, "/", strempty(prefix), hash, escaped_etag ? "." : "",
4600a396	193	strempty(escaped_etag), strempty(suffix));
9818005d JS	194	if (!path)
	195	return -ENOMEM;
	196	}
	197
56ebfaf1 LP	198	*ret = path;
	199	return 0;
	200	}
85dbc41d	201
91359193	202	int pull_make_auxiliary_job(
9854730b LP	203	PullJob **ret,
9854730b LP	204	const char *url,
91359193 LP	205	int (strip_suffixes)(const char name, char **ret),
91359193 LP	206	const char *suffix,
9854730b LP	207	CurlGlue *glue,
	208	PullJobFinished on_finished,
	209	void *userdata) {
	210
91359193	211	_cleanup_free_ char last_component = NULL, ll = NULL, *auxiliary_url = NULL;
9854730b LP	212	_cleanup_(pull_job_unrefp) PullJob *job = NULL;
	213	const char *q;
	214	int r;
	215
	216	assert(ret);
	217	assert(url);
91359193	218	assert(strip_suffixes);
9854730b LP	219	assert(glue);
	220
	221	r = import_url_last_component(url, &last_component);
	222	if (r < 0)
	223	return r;
	224
91359193	225	r = strip_suffixes(last_component, &ll);
9854730b LP	226	if (r < 0)
	227	return r;
	228
91359193	229	q = strjoina(ll, suffix);
9854730b	230
91359193	231	r = import_url_change_last_component(url, q, &auxiliary_url);
9854730b LP	232	if (r < 0)
	233	return r;
	234
91359193	235	r = pull_job_new(&job, auxiliary_url, glue, userdata);
9854730b LP	236	if (r < 0)
	237	return r;
	238
	239	job->on_finished = on_finished;
	240	job->compressed_max = job->uncompressed_max = 1ULL * 1024ULL * 1024ULL;
	241
1cc6c93a	242	*ret = TAKE_PTR(job);
9854730b LP	243
	244	return 0;
	245	}
	246
dc2c282b LP	247	int pull_make_verification_jobs(
	248	PullJob **ret_checksum_job,
	249	PullJob **ret_signature_job,
98c38001 LP	250	ImportVerify verify,
	251	const char *url,
	252	CurlGlue *glue,
dc2c282b	253	PullJobFinished on_finished,
98c38001 LP	254	void *userdata) {
98c38001 LP	255
dc2c282b	256	_cleanup_(pull_job_unrefp) PullJob checksum_job = NULL, signature_job = NULL;
98c38001 LP	257	int r;
	258
	259	assert(ret_checksum_job);
	260	assert(ret_signature_job);
	261	assert(verify >= 0);
	262	assert(verify < _IMPORT_VERIFY_MAX);
	263	assert(url);
	264	assert(glue);
	265
	266	if (verify != IMPORT_VERIFY_NO) {
697be0be	267	_cleanup_free_ char checksum_url = NULL, fn = NULL;
c6cb8daf	268	const char *chksums = NULL;
98c38001	269
697be0be TB	270	/* Queue jobs for the checksum file for the image. */
	271	r = import_url_last_component(url, &fn);
	272	if (r < 0)
	273	return r;
	274
	275	chksums = strjoina(fn, ".sha256");
	276
	277	r = import_url_change_last_component(url, chksums, &checksum_url);
98c38001 LP	278	if (r < 0)
	279	return r;
	280
dc2c282b	281	r = pull_job_new(&checksum_job, checksum_url, glue, userdata);
98c38001 LP	282	if (r < 0)
	283	return r;
	284
	285	checksum_job->on_finished = on_finished;
	286	checksum_job->uncompressed_max = checksum_job->compressed_max = 1ULL * 1024ULL * 1024ULL;
	287	}
	288
	289	if (verify == IMPORT_VERIFY_SIGNATURE) {
	290	_cleanup_free_ char *signature_url = NULL;
	291
	292	/* Queue job for the SHA256SUMS.gpg file for the image. */
	293	r = import_url_change_last_component(url, "SHA256SUMS.gpg", &signature_url);
	294	if (r < 0)
	295	return r;
	296
dc2c282b	297	r = pull_job_new(&signature_job, signature_url, glue, userdata);
98c38001 LP	298	if (r < 0)
	299	return r;
	300
	301	signature_job->on_finished = on_finished;
	302	signature_job->uncompressed_max = signature_job->compressed_max = 1ULL * 1024ULL * 1024ULL;
	303	}
	304
c20307fd LP	305	*ret_checksum_job = TAKE_PTR(checksum_job);
c20307fd LP	306	*ret_signature_job = TAKE_PTR(signature_job);
98c38001 LP	307
	308	return 0;
	309	}
	310
91359193	311	static int verify_one(PullJob checksum_job, PullJob job) {
98c38001	312	_cleanup_free_ char *fn = NULL;
91359193	313	const char line, p;
98c38001 LP	314	int r;
98c38001 LP	315
91359193	316	assert(checksum_job);
98c38001	317
91359193	318	if (!job)
98c38001 LP	319	return 0;
98c38001 LP	320
91359193	321	assert(IN_SET(job->state, PULL_JOB_DONE, PULL_JOB_FAILED));
98c38001	322
91359193 LP	323	/* Don't verify the checksum if we didn't actually successfully download something new */
	324	if (job->state != PULL_JOB_DONE)
	325	return 0;
	326	if (job->error != 0)
	327	return 0;
	328	if (job->etag_exists)
	329	return 0;
98c38001	330
91359193 LP	331	assert(job->calc_checksum);
	332	assert(job->checksum);
	333
	334	r = import_url_last_component(job->url, &fn);
98c38001 LP	335	if (r < 0)
	336	return log_oom();
	337
baaa35ad ZJS	338	if (!filename_is_valid(fn))
	339	return log_error_errno(SYNTHETIC_ERRNO(EBADMSG),
	340	"Cannot verify checksum, could not determine server-side file name.");
98c38001	341
91359193	342	line = strjoina(job->checksum, " *", fn, "\n");
98c38001 LP	343
	344	p = memmem(checksum_job->payload,
	345	checksum_job->payload_size,
	346	line,
	347	strlen(line));
	348
697be0be TB	349	if (!p) {
	350	line = strjoina(job->checksum, " ", fn, "\n");
	351
	352	p = memmem(checksum_job->payload,
	353	checksum_job->payload_size,
	354	line,
	355	strlen(line));
	356	}
	357
baaa35ad ZJS	358	if (!p \|\| (p != (char*) checksum_job->payload && p[-1] != '\n'))
	359	return log_error_errno(SYNTHETIC_ERRNO(EBADMSG),
	360	"DOWNLOAD INVALID: Checksum of %s file did not checkout, file has been tampered with.", fn);
98c38001	361
91359193 LP	362	log_info("SHA256 checksum of %s is valid.", job->url);
	363	return 1;
	364	}
98c38001	365
ac71ece3 LP	366	static int verify_gpg(
	367	const void *payload, size_t payload_size,
	368	const void *signature, size_t signature_size) {
9854730b	369
91359193	370	_cleanup_close_pair_ int gpg_pipe[2] = { -1, -1 };
91359193 LP	371	char sig_file_path[] = "/tmp/sigXXXXXX", gpg_home[] = "/tmp/gpghomeXXXXXX";
	372	_cleanup_(sigkill_waitp) pid_t pid = 0;
	373	bool gpg_home_created = false;
	374	int r;
9854730b	375
ac71ece3 LP	376	assert(payload \|\| payload_size == 0);
ac71ece3 LP	377	assert(signature \|\| signature_size == 0);
98c38001 LP	378
	379	r = pipe2(gpg_pipe, O_CLOEXEC);
	380	if (r < 0)
0100b6e1	381	return log_error_errno(errno, "Failed to create pipe for gpg: %m");
98c38001	382
ac71ece3 LP	383	if (signature_size > 0) {
ac71ece3 LP	384	_cleanup_close_ int sig_file = -1;
98c38001	385
ac71ece3 LP	386	sig_file = mkostemp(sig_file_path, O_RDWR);
	387	if (sig_file < 0)
	388	return log_error_errno(errno, "Failed to create temporary file: %m");
	389
	390	r = loop_write(sig_file, signature, signature_size, false);
	391	if (r < 0) {
	392	log_error_errno(r, "Failed to write to temporary file: %m");
	393	goto finish;
	394	}
98c38001 LP	395	}
98c38001 LP	396
0acfdffe	397	if (!mkdtemp(gpg_home)) {
5238e957	398	r = log_error_errno(errno, "Failed to create temporary home for gpg: %m");
0acfdffe LP	399	goto finish;
	400	}
	401
	402	gpg_home_created = true;
	403
b6e1fff1	404	r = safe_fork("(gpg)", FORK_RESET_SIGNALS\|FORK_DEATHSIG\|FORK_LOG, &pid);
4c253ed1	405	if (r < 0)
b6e1fff1	406	return r;
4c253ed1	407	if (r == 0) {
98c38001 LP	408	const char *cmd[] = {
	409	"gpg",
	410	"--no-options",
	411	"--no-default-keyring",
	412	"--no-auto-key-locate",
	413	"--no-auto-check-trustdb",
	414	"--batch",
	415	"--trust-model=always",
0acfdffe LP	416	NULL, /* --homedir= */
0acfdffe LP	417	NULL, /* --keyring= */
98c38001 LP	418	NULL, /* --verify */
	419	NULL, /* signature file */
	420	NULL, /* dash */
	421	NULL /* trailing NULL */
	422	};
ac71ece3	423	size_t k = ELEMENTSOF(cmd) - 6;
98c38001 LP	424
	425	/* Child */
	426
98c38001 LP	427	gpg_pipe[1] = safe_close(gpg_pipe[1]);
98c38001 LP	428
2b33ab09	429	r = rearrange_stdio(gpg_pipe[0], -1, STDERR_FILENO);
046a82c1	430	if (r < 0) {
2b33ab09	431	log_error_errno(r, "Failed to rearrange stdin/stdout: %m");
98c38001 LP	432	_exit(EXIT_FAILURE);
	433	}
	434
595225af LP	435	(void) rlimit_nofile_safe();
595225af LP	436
0acfdffe LP	437	cmd[k++] = strjoina("--homedir=", gpg_home);
0acfdffe LP	438
ac71ece3	439	/* We add the user keyring only to the command line arguments, if it's around since gpg fails
98c38001 LP	440	* otherwise. */
	441	if (access(USER_KEYRING_PATH, F_OK) >= 0)
	442	cmd[k++] = "--keyring=" USER_KEYRING_PATH;
1c49d1ba LP	443	else
1c49d1ba LP	444	cmd[k++] = "--keyring=" VENDOR_KEYRING_PATH;
98c38001 LP	445
98c38001 LP	446	cmd[k++] = "--verify";
ac71ece3	447	if (signature) {
697be0be TB	448	cmd[k++] = sig_file_path;
	449	cmd[k++] = "-";
	450	cmd[k++] = NULL;
	451	}
98c38001	452
0acfdffe	453	execvp("gpg2", (char * const *) cmd);
98c38001 LP	454	execvp("gpg", (char * const *) cmd);
	455	log_error_errno(errno, "Failed to execute gpg: %m");
	456	_exit(EXIT_FAILURE);
	457	}
	458
	459	gpg_pipe[0] = safe_close(gpg_pipe[0]);
	460
ac71ece3	461	r = loop_write(gpg_pipe[1], payload, payload_size, false);
98c38001 LP	462	if (r < 0) {
	463	log_error_errno(r, "Failed to write to pipe: %m");
	464	goto finish;
	465	}
	466
	467	gpg_pipe[1] = safe_close(gpg_pipe[1]);
	468
7d4904fe	469	r = wait_for_terminate_and_check("gpg", pid, WAIT_LOG_ABNORMAL);
98c38001 LP	470	pid = 0;
	471	if (r < 0)
	472	goto finish;
b4a34311	473	if (r != EXIT_SUCCESS) {
9854730b	474	log_error("DOWNLOAD INVALID: Signature verification failed.");
98c38001 LP	475	r = -EBADMSG;
	476	} else {
	477	log_info("Signature verification succeeded.");
	478	r = 0;
	479	}
	480
	481	finish:
ac71ece3 LP	482	if (signature_size > 0)
ac71ece3 LP	483	(void) unlink(sig_file_path);
98c38001	484
0acfdffe	485	if (gpg_home_created)
c6878637	486	(void) rm_rf(gpg_home, REMOVE_ROOT\|REMOVE_PHYSICAL);
0acfdffe	487
98c38001 LP	488	return r;
98c38001 LP	489	}
f14717a7	490
ac71ece3 LP	491	int pull_verify(ImportVerify verify,
	492	PullJob *main_job,
	493	PullJob *roothash_job,
	494	PullJob *settings_job,
	495	PullJob *checksum_job,
	496	PullJob *signature_job) {
	497
	498	VerificationStyle style;
	499	int r;
	500
	501	assert(main_job);
	502	assert(main_job->state == PULL_JOB_DONE);
	503
	504	if (verify == IMPORT_VERIFY_NO)
	505	return 0;
	506
	507	assert(main_job->calc_checksum);
	508	assert(main_job->checksum);
	509	assert(checksum_job);
	510	assert(checksum_job->state == PULL_JOB_DONE);
	511
	512	if (!checksum_job->payload \|\| checksum_job->payload_size <= 0)
	513	return log_error_errno(SYNTHETIC_ERRNO(EBADMSG),
	514	"Checksum is empty, cannot verify.");
	515
	516	r = verify_one(checksum_job, main_job);
	517	if (r < 0)
	518	return r;
	519
	520	r = verify_one(checksum_job, roothash_job);
	521	if (r < 0)
	522	return r;
	523
	524	r = verify_one(checksum_job, settings_job);
	525	if (r < 0)
	526	return r;
	527
	528	if (verify == IMPORT_VERIFY_CHECKSUM)
	529	return 0;
	530
	531	r = verification_style_from_url(checksum_job->url, &style);
	532	if (r < 0)
	533	return log_error_errno(r, "Failed to determine verification style from URL '%s': %m", checksum_job->url);
	534
	535	if (style == VERIFICATION_PER_DIRECTORY) {
	536	assert(signature_job);
	537	assert(signature_job->state == PULL_JOB_DONE);
	538
	539	if (!signature_job->payload \|\| signature_job->payload_size <= 0)
	540	return log_error_errno(SYNTHETIC_ERRNO(EBADMSG),
	541	"Signature is empty, cannot verify.");
	542
	543	return verify_gpg(checksum_job->payload, checksum_job->payload_size, signature_job->payload, signature_job->payload_size);
	544	} else
	545	return verify_gpg(checksum_job->payload, checksum_job->payload_size, NULL, 0);
	546	}
	547
f14717a7 LP	548	int verification_style_from_url(const char url, VerificationStyle ret) {
	549	_cleanup_free_ char *last = NULL;
	550	int r;
	551
	552	assert(url);
	553	assert(ret);
	554
	555	/* Determines which kind of verification style is appropriate for this url */
	556
	557	r = import_url_last_component(url, &last);
	558	if (r < 0)
	559	return r;
	560
	561	if (streq(last, "SHA256SUMS")) {
	562	*ret = VERIFICATION_PER_DIRECTORY;
	563	return 0;
	564	}
	565
	566	if (endswith(last, ".sha256")) {
	567	*ret = VERIFICATION_PER_FILE;
	568	return 0;
	569	}
	570
	571	return -EINVAL;
	572	}
	573
	574	int pull_job_restart_with_sha256sum(PullJob j, char *ret) {
	575	VerificationStyle style;
	576	int r;
	577
	578	assert(j);
	579
	580	/* Generic implementation of a PullJobNotFound handler, that restarts the job requesting SHA256SUMS */
	581
	582	r = verification_style_from_url(j->url, &style);
	583	if (r < 0)
	584	return log_error_errno(r, "Failed to determine verification style of URL '%s': %m", j->url);
	585
	586	if (style == VERIFICATION_PER_DIRECTORY) /* Nothing to do anymore */
	587	return 0;
	588
	589	assert(style == VERIFICATION_PER_FILE); /* This must have been .sha256 style URL before */
	590
	591	log_debug("Got 404 for %s, now trying to get SHA256SUMS instead.", j->url);
	592
	593	r = import_url_change_last_component(j->url, "SHA256SUMS", ret);
	594	if (r < 0)
	595	return log_error_errno(r, "Failed to replace SHA256SUMS suffix: %m");
	596
	597	return 1;
	598	}