From 3c60711f836b151b8f361098475c3b0cd162dd17 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Wed, 20 Apr 2022 15:31:01 +0200 Subject: seedrng: remove some global variables - Remove global variables and pass dfd by value, opened once instead of twice, which shaves off some more bytes. function old new delta seedrng_main 1086 1088 +2 seed_dir 8 - -8 non_creditable_seed 8 - -8 lock_file 8 - -8 creditable_seed 8 - -8 seed_from_file_if_exists 456 426 -30 ------------------------------------------------------------------------------ (add/remove: 0/4 grow/shrink: 1/1 up/down: 2/-62) Total: -60 bytes text data bss dec hex filename 976236 4227 1848 982311 efd27 busybox_old 976208 4227 1816 982251 efceb busybox_unstripped Signed-off-by: Jason A. Donenfeld Signed-off-by: Bernhard Reutner-Fischer --- util-linux/seedrng.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) (limited to 'util-linux') diff --git a/util-linux/seedrng.c b/util-linux/seedrng.c index 1bceae405..53be5048a 100644 --- a/util-linux/seedrng.c +++ b/util-linux/seedrng.c @@ -21,7 +21,7 @@ */ //config:config SEEDRNG -//config: bool "seedrng (2.5 kb)" +//config: bool "seedrng (2.4 kb)" //config: default y //config: help //config: Seed the kernel RNG from seed files, meant to be called @@ -76,8 +76,6 @@ #define CREDITABLE_SEED_NAME "seed.credit" #define NON_CREDITABLE_SEED_NAME "seed.no-credit" -static char *seed_dir, *lock_file, *creditable_seed, *non_creditable_seed; - enum seedrng_lengths { MIN_SEED_LEN = SHA256_OUTSIZE, MAX_SEED_LEN = 512 @@ -153,18 +151,12 @@ static int seed_rng(uint8_t *seed, size_t len, bool credit) return ret ? -1 : 0; } -static int seed_from_file_if_exists(const char *filename, bool credit, sha256_ctx_t *hash) +static int seed_from_file_if_exists(const char *filename, int dfd, bool credit, sha256_ctx_t *hash) { uint8_t seed[MAX_SEED_LEN]; ssize_t seed_len; - int dfd = -1, ret = 0; + int ret = 0; - dfd = open(seed_dir, O_DIRECTORY | O_RDONLY); - if (dfd < 0) { - ret = -errno; - bb_simple_perror_msg("unable to open seed directory"); - goto out; - } seed_len = open_read_close(filename, seed, sizeof(seed)); if (seed_len < 0) { if (errno != ENOENT) { @@ -189,8 +181,6 @@ static int seed_from_file_if_exists(const char *filename, bool credit, sha256_ct if (ret < 0) bb_simple_perror_msg("unable to seed"); out: - if (ENABLE_FEATURE_CLEAN_UP && dfd >= 0) - close(dfd); errno = -ret; return ret ? -1 : 0; } @@ -200,7 +190,8 @@ int seedrng_main(int argc UNUSED_PARAM, char *argv[]) { static const char seedrng_prefix[] = "SeedRNG v1 Old+New Prefix"; static const char seedrng_failure[] = "SeedRNG v1 No New Seed Failure"; - int ret, fd = -1, lock, program_ret = 0; + char *seed_dir, *lock_file, *creditable_seed, *non_creditable_seed; + int ret, fd = -1, dfd = -1, lock, program_ret = 0; uint8_t new_seed[MAX_SEED_LEN]; size_t new_seed_len; bool new_seed_creditable; @@ -245,6 +236,13 @@ int seedrng_main(int argc UNUSED_PARAM, char *argv[]) goto out; } + dfd = open(seed_dir, O_DIRECTORY | O_RDONLY); + if (dfd < 0) { + bb_simple_perror_msg("unable to open seed directory"); + program_ret = 1; + goto out; + } + sha256_begin(&hash); sha256_hash(&hash, seedrng_prefix, strlen(seedrng_prefix)); clock_gettime(CLOCK_REALTIME, ×tamp); @@ -252,10 +250,10 @@ int seedrng_main(int argc UNUSED_PARAM, char *argv[]) clock_gettime(CLOCK_BOOTTIME, ×tamp); sha256_hash(&hash, ×tamp, sizeof(timestamp)); - ret = seed_from_file_if_exists(non_creditable_seed, false, &hash); + ret = seed_from_file_if_exists(non_creditable_seed, dfd, false, &hash); if (ret < 0) program_ret |= 1 << 1; - ret = seed_from_file_if_exists(creditable_seed, !skip_credit, &hash); + ret = seed_from_file_if_exists(creditable_seed, dfd, !skip_credit, &hash); if (ret < 0) program_ret |= 1 << 2; @@ -290,6 +288,8 @@ int seedrng_main(int argc UNUSED_PARAM, char *argv[]) out: if (ENABLE_FEATURE_CLEAN_UP && fd >= 0) close(fd); + if (ENABLE_FEATURE_CLEAN_UP && dfd >= 0) + close(dfd); if (ENABLE_FEATURE_CLEAN_UP && lock >= 0) close(lock); return program_ret; -- cgit v1.2.3-55-g6feb