diff options
Diffstat (limited to 'src/journal/journalctl-authenticate.c')
| -rw-r--r-- | src/journal/journalctl-authenticate.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/src/journal/journalctl-authenticate.c b/src/journal/journalctl-authenticate.c new file mode 100644 index 0000000..10630f5 --- /dev/null +++ b/src/journal/journalctl-authenticate.c @@ -0,0 +1,207 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include "chattr-util.h" +#include "errno-util.h" +#include "fd-util.h" +#include "fs-util.h" +#include "fsprg.h" +#include "hostname-util.h" +#include "io-util.h" +#include "journal-authenticate.h" +#include "journalctl.h" +#include "journalctl-authenticate.h" +#include "memstream-util.h" +#include "path-util.h" +#include "qrcode-util.h" +#include "random-util.h" +#include "stat-util.h" +#include "terminal-util.h" +#include "tmpfile-util.h" + +static int format_key( + const void *seed, + size_t seed_size, + uint64_t start, + uint64_t interval, + char **ret) { + + _cleanup_(memstream_done) MemStream m = {}; + FILE *f; + + assert(seed); + assert(seed_size > 0); + assert(ret); + + f = memstream_init(&m); + if (!f) + return -ENOMEM; + + for (size_t i = 0; i < seed_size; i++) { + if (i > 0 && i % 3 == 0) + fputc('-', f); + fprintf(f, "%02x", ((uint8_t*) seed)[i]); + } + + fprintf(f, "/%"PRIx64"-%"PRIx64, start, interval); + + return memstream_finalize(&m, ret, NULL); +} + +int action_setup_keys(void) { + _cleanup_(unlink_and_freep) char *tmpfile = NULL; + _cleanup_close_ int fd = -EBADF; + _cleanup_free_ char *path = NULL; + size_t mpk_size, seed_size, state_size; + uint8_t *mpk, *seed, *state; + sd_id128_t machine, boot; + uint64_t n; + int r; + + assert(arg_action == ACTION_SETUP_KEYS); + + r = is_dir("/var/log/journal/", /* follow = */ false); + if (r == 0) + return log_error_errno(SYNTHETIC_ERRNO(ENOTDIR), + "/var/log/journal is not a directory, must be using persistent logging for FSS."); + if (r == -ENOENT) + return log_error_errno(r, "Directory /var/log/journal/ does not exist, must be using persistent logging for FSS."); + if (r < 0) + return log_error_errno(r, "Failed to check if /var/log/journal/ is a directory: %m"); + + r = sd_id128_get_machine(&machine); + if (r < 0) + return log_error_errno(r, "Failed to get machine ID: %m"); + + r = sd_id128_get_boot(&boot); + if (r < 0) + return log_error_errno(r, "Failed to get boot ID: %m"); + + path = path_join("/var/log/journal/", SD_ID128_TO_STRING(machine), "/fss"); + if (!path) + return log_oom(); + + if (arg_force) { + if (unlink(path) < 0 && errno != ENOENT) + return log_error_errno(errno, "Failed to remove \"%s\": %m", path); + } else if (access(path, F_OK) >= 0) + return log_error_errno(SYNTHETIC_ERRNO(EEXIST), + "Sealing key file %s exists already. Use --force to recreate.", path); + + mpk_size = FSPRG_mskinbytes(FSPRG_RECOMMENDED_SECPAR); + mpk = alloca_safe(mpk_size); + + seed_size = FSPRG_RECOMMENDED_SEEDLEN; + seed = alloca_safe(seed_size); + + state_size = FSPRG_stateinbytes(FSPRG_RECOMMENDED_SECPAR); + state = alloca_safe(state_size); + + log_info("Generating seed..."); + r = crypto_random_bytes(seed, seed_size); + if (r < 0) + return log_error_errno(r, "Failed to acquire random seed: %m"); + + log_info("Generating key pair..."); + r = FSPRG_GenMK(NULL, mpk, seed, seed_size, FSPRG_RECOMMENDED_SECPAR); + if (r < 0) + return log_error_errno(r, "Failed to generate key pair: %m"); + + log_info("Generating sealing key..."); + r = FSPRG_GenState0(state, mpk, seed, seed_size); + if (r < 0) + return log_error_errno(r, "Failed to generate sealing key: %m"); + + assert(arg_interval > 0); + n = now(CLOCK_REALTIME); + n /= arg_interval; + + fd = open_tmpfile_linkable(path, O_WRONLY|O_CLOEXEC, &tmpfile); + if (fd < 0) + return log_error_errno(fd, "Failed to open a temporary file for %s: %m", path); + + r = chattr_secret(fd, CHATTR_WARN_UNSUPPORTED_FLAGS); + if (r < 0) + log_full_errno(ERRNO_IS_NOT_SUPPORTED(r) ? LOG_DEBUG : LOG_WARNING, + r, "Failed to set file attributes on a temporary file for '%s', ignoring: %m", path); + + struct FSSHeader h = { + .signature = { 'K', 'S', 'H', 'H', 'R', 'H', 'L', 'P' }, + .machine_id = machine, + .boot_id = boot, + .header_size = htole64(sizeof(h)), + .start_usec = htole64(n * arg_interval), + .interval_usec = htole64(arg_interval), + .fsprg_secpar = htole16(FSPRG_RECOMMENDED_SECPAR), + .fsprg_state_size = htole64(state_size), + }; + + r = loop_write(fd, &h, sizeof(h)); + if (r < 0) + return log_error_errno(r, "Failed to write header: %m"); + + r = loop_write(fd, state, state_size); + if (r < 0) + return log_error_errno(r, "Failed to write state: %m"); + + r = link_tmpfile(fd, tmpfile, path, /* flags = */ 0); + if (r < 0) + return log_error_errno(r, "Failed to link file: %m"); + + tmpfile = mfree(tmpfile); + + _cleanup_free_ char *key = NULL; + r = format_key(seed, seed_size, n, arg_interval, &key); + if (r < 0) + return r; + + if (!on_tty()) { + /* If we are not on a TTY, show only the key. */ + puts(key); + return 0; + } + + _cleanup_free_ char *hn = NULL; + hn = gethostname_malloc(); + if (hn) + hostname_cleanup(hn); + + fprintf(stderr, + "\nNew keys have been generated for host %s%s" SD_ID128_FORMAT_STR ".\n" + "\n" + "The %ssecret sealing key%s has been written to the following local file.\n" + "This key file is automatically updated when the sealing key is advanced.\n" + "It should not be used on multiple hosts.\n" + "\n" + "\t%s\n" + "\n" + "The sealing key is automatically changed every %s.\n" + "\n" + "Please write down the following %ssecret verification key%s. It should be stored\n" + "in a safe location and should not be saved locally on disk.\n" + "\n\t%s", + strempty(hn), hn ? "/" : "", + SD_ID128_FORMAT_VAL(machine), + ansi_highlight(), ansi_normal(), + path, + FORMAT_TIMESPAN(arg_interval, 0), + ansi_highlight(), ansi_normal(), + ansi_highlight_red()); + fflush(stderr); + + puts(key); + + fputs(ansi_normal(), stderr); + +#if HAVE_QRENCODE + _cleanup_free_ char *url = NULL; + url = strjoin("fss://", key, "?machine=", SD_ID128_TO_STRING(machine), hn ? ";hostname=" : "", hn); + if (!url) + return log_oom(); + + (void) print_qrcode(stderr, + "To transfer the verification key to your phone scan the QR code below", + url); +#endif + + return 0; +} |