diff options
Diffstat (limited to 'src/random-seed/random-seed.c')
| -rw-r--r-- | src/random-seed/random-seed.c | 111 |
1 files changed, 2 insertions, 109 deletions
diff --git a/src/random-seed/random-seed.c b/src/random-seed/random-seed.c index a50fdc12ae..c3353e5518 100644 --- a/src/random-seed/random-seed.c +++ b/src/random-seed/random-seed.c @@ -16,10 +16,7 @@ #include "alloc-util.h" #include "build.h" -#include "chase-symlinks.h" -#include "efi-loader.h" #include "fd-util.h" -#include "find-esp.h" #include "fs-util.h" #include "io-util.h" #include "log.h" @@ -27,17 +24,13 @@ #include "missing_random.h" #include "missing_syscall.h" #include "mkdir.h" -#include "parse-argument.h" #include "parse-util.h" -#include "path-util.h" #include "pretty-print.h" #include "random-util.h" #include "string-table.h" #include "string-util.h" -#include "strv.h" #include "sync-util.h" #include "sha256.h" -#include "terminal-util.h" #include "xattr-util.h" typedef enum SeedAction { @@ -313,100 +306,6 @@ static int save_seed_file( return 0; } -static int refresh_boot_seed(void) { - uint8_t buffer[RANDOM_EFI_SEED_SIZE]; - struct sha256_ctx hash_state; - _cleanup_free_ void *seed_file_bytes = NULL; - _cleanup_free_ char *esp_path = NULL; - _cleanup_close_ int seed_fd = -EBADF, dir_fd = -EBADF; - size_t len; - ssize_t n; - int r; - - assert_cc(RANDOM_EFI_SEED_SIZE == SHA256_DIGEST_SIZE); - - r = find_esp_and_warn(NULL, NULL, /* unprivileged_mode= */ false, &esp_path, - NULL, NULL, NULL, NULL, NULL); - if (r < 0) { - if (r == -ENOKEY) { - log_debug_errno(r, "Couldn't find any ESP, so not updating ESP random seed."); - return 0; - } - return r; /* find_esp_and_warn() already logged */ - } - - r = chase_symlinks("/loader", esp_path, CHASE_PREFIX_ROOT|CHASE_PROHIBIT_SYMLINKS, NULL, &dir_fd); - if (r < 0) { - if (r == -ENOENT) { - log_debug_errno(r, "Couldn't find ESP loader directory, so not updating ESP random seed."); - return 0; - } - return log_error_errno(r, "Failed to open ESP loader directory: %m"); - } - seed_fd = openat(dir_fd, "random-seed", O_NOFOLLOW|O_RDWR|O_CLOEXEC|O_NOCTTY); - if (seed_fd < 0 && errno == ENOENT) { - uint64_t features; - r = efi_loader_get_features(&features); - if (r == 0 && FLAGS_SET(features, EFI_LOADER_FEATURE_RANDOM_SEED)) - seed_fd = openat(dir_fd, "random-seed", O_CREAT|O_EXCL|O_RDWR|O_CLOEXEC|O_NOCTTY, 0600); - else { - log_debug_errno(seed_fd, "Couldn't find ESP random seed, and not booted with systemd-boot, so not updating ESP random seed."); - return 0; - } - } - if (seed_fd < 0) - return log_error_errno(errno, "Failed to open EFI seed path: %m"); - r = random_seed_size(seed_fd, &len); - if (r < 0) - return log_error_errno(r, "Failed to determine EFI seed path length: %m"); - seed_file_bytes = malloc(len); - if (!seed_file_bytes) - return log_oom(); - n = loop_read(seed_fd, seed_file_bytes, len, false); - if (n < 0) - return log_error_errno(n, "Failed to read EFI seed file: %m"); - - /* Hash the old seed in so that we never regress in entropy. */ - sha256_init_ctx(&hash_state); - sha256_process_bytes_and_size(seed_file_bytes, n, &hash_state); - - /* We're doing this opportunistically, so if the seeding dance before didn't manage to initialize the - * RNG, there's no point in doing it here. Secondly, getrandom(GRND_NONBLOCK) has been around longer - * than EFI seeding anyway, so there's no point in having non-getrandom() fallbacks here. So if this - * fails, just return early to cut our losses. */ - n = getrandom(buffer, sizeof(buffer), GRND_NONBLOCK); - if (n < 0) { - if (errno == EAGAIN) { - log_debug_errno(errno, "Random pool not initialized yet, so skipping EFI seed update"); - return 0; - } - if (errno == ENOSYS) { - log_debug_errno(errno, "getrandom() not available, so skipping EFI seed update"); - return 0; - } - return log_error_errno(errno, "Failed to generate random bytes for EFI seed: %m"); - } - assert(n == sizeof(buffer)); - - /* Hash the new seed into the state containing the old one to generate our final seed. */ - sha256_process_bytes_and_size(buffer, n, &hash_state); - sha256_finish_ctx(&hash_state, buffer); - - if (lseek(seed_fd, 0, SEEK_SET) < 0) - return log_error_errno(errno, "Failed to seek to beginning of EFI seed file: %m"); - r = loop_write(seed_fd, buffer, sizeof(buffer), false); - if (r < 0) - return log_error_errno(r, "Failed to write new EFI seed file: %m"); - if (ftruncate(seed_fd, sizeof(buffer)) < 0) - return log_error_errno(errno, "Failed to truncate EFI seed file: %m"); - r = fsync_full(seed_fd); - if (r < 0) - return log_error_errno(r, "Failed to fsync EFI seed file: %m"); - - log_debug("Updated random seed in ESP"); - return 0; -} - static int help(int argc, char *argv[], void *userdata) { _cleanup_free_ char *link = NULL; int r; @@ -524,10 +423,7 @@ static int run(int argc, char *argv[]) { log_full_errno(level, open_rw_error, "Failed to open " RANDOM_SEED " for writing: %m"); log_full_errno(level, errno, "Failed to open " RANDOM_SEED " for reading: %m"); - r = -errno; - - (void) refresh_boot_seed(); - return missing ? 0 : r; + return missing ? 0 : -errno; } } else write_seed_file = true; @@ -537,7 +433,6 @@ static int run(int argc, char *argv[]) { break; case ACTION_SAVE: - (void) refresh_boot_seed(); seed_fd = open(RANDOM_SEED, O_WRONLY|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600); if (seed_fd < 0) return log_error_errno(errno, "Failed to open " RANDOM_SEED ": %m"); @@ -555,11 +450,9 @@ static int run(int argc, char *argv[]) { if (r < 0) return r; - if (read_seed_file) { + if (read_seed_file) r = load_seed_file(seed_fd, random_fd, seed_size, write_seed_file ? &hash_state : NULL); - (void) refresh_boot_seed(); - } if (r >= 0 && write_seed_file) r = save_seed_file(seed_fd, random_fd, seed_size, synchronous, hash_state); |