401356511
Denys Vlasenko
2022-04-27
Subject
seedrng: remove unnecessary zero-filling of local variables
Binary
No binary (build failed)
Architecture & Compiler Flags
—
Build Log
(log yok)
Commit Diff GitHub →
util-linux/seedrng.c+11 -8
| @@ -54,20 +54,23 @@ | |
| #define CREDITABLE_SEED_NAME "seed.credit" | |
| #define NON_CREDITABLE_SEED_NAME "seed.no-credit" | |
| - | enum seedrng_lengths { |
| + | enum { |
| MIN_SEED_LEN = SHA256_OUTSIZE, | |
| MAX_SEED_LEN = 512 | |
| }; | |
| static size_t determine_optimal_seed_len(void) | |
| { | |
| - | char poolsize_str[11] = { 0 }; |
| - | unsigned long poolsize; |
| + | char poolsize_str[12]; |
| + | unsigned poolsize; |
| + | int n; |
| - | if (open_read_close("/proc/sys/kernel/random/poolsize", poolsize_str, sizeof(poolsize_str) - 1) < 0) { |
| + | n = open_read_close("/proc/sys/kernel/random/poolsize", poolsize_str, sizeof(poolsize_str) - 1); |
| + | if (n < 0) { |
| bb_perror_msg("unable to determine pool size, assuming %u bits", MIN_SEED_LEN * 8); | |
| return MIN_SEED_LEN; | |
| } | |
| + | poolsize_str[n] = '\0'; |
| poolsize = (bb_strtoul(poolsize_str, NULL, 10) + 7) / 8; | |
| return MAX(MIN(poolsize, MAX_SEED_LEN), MIN_SEED_LEN); | |
| } | |
| @@ -159,7 +162,7 @@ static int seed_from_file_if_exists(const char *filename, int dfd, bool credit, | |
| int seedrng_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE; | |
| int seedrng_main(int argc UNUSED_PARAM, char *argv[]) | |
| { | |
| - | const char *seed_dir = DEFAULT_SEED_DIR, *creditable_seed, *non_creditable_seed; |
| + | const char *seed_dir, *creditable_seed, *non_creditable_seed; |
| int fd, dfd, program_ret = 0; | |
| uint8_t new_seed[MAX_SEED_LEN]; | |
| size_t new_seed_len; | |
| @@ -178,10 +181,8 @@ int seedrng_main(int argc UNUSED_PARAM, char *argv[]) | |
| ; | |
| #endif | |
| + | seed_dir = DEFAULT_SEED_DIR; |
| skip_credit = getopt32long(argv, "d:n", longopts, &seed_dir) & OPT_n; | |
| - | creditable_seed = concat_path_file(seed_dir, CREDITABLE_SEED_NAME); |
| - | non_creditable_seed = concat_path_file(seed_dir, NON_CREDITABLE_SEED_NAME); |
| - | |
| umask(0077); | |
| if (getuid()) | |
| bb_simple_error_msg_and_die(bb_msg_you_must_be_root); | |
| @@ -200,6 +201,8 @@ int seedrng_main(int argc UNUSED_PARAM, char *argv[]) | |
| clock_gettime(CLOCK_BOOTTIME, ×tamp); | |
| sha256_hash(&hash, ×tamp, sizeof(timestamp)); | |
| + | creditable_seed = concat_path_file(seed_dir, CREDITABLE_SEED_NAME); |
| + | non_creditable_seed = concat_path_file(seed_dir, NON_CREDITABLE_SEED_NAME); |
| for (int i = 1; i < 3; ++i) { | |
| if (seed_from_file_if_exists(i == 1 ? non_creditable_seed : creditable_seed, | |
| dfd, i == 1 ? false : !skip_credit, &hash) < 0) | |