diff options
| -rw-r--r-- | passt.c | 30 | ||||
| -rw-r--r-- | util.c | 54 | ||||
| -rw-r--r-- | util.h | 2 |
3 files changed, 57 insertions, 29 deletions
@@ -36,9 +36,6 @@ #include <sys/prctl.h> #include <netinet/if_ether.h> #include <libgen.h> -#ifdef HAS_GETRANDOM -#include <sys/random.h> -#endif #include "util.h" #include "passt.h" @@ -118,32 +115,7 @@ static void post_handler(struct ctx *c, const struct timespec *now) */ static void secret_init(struct ctx *c) { -#ifndef HAS_GETRANDOM - int dev_random = open("/dev/random", O_RDONLY); - unsigned int random_read = 0; - - while (dev_random && random_read < sizeof(c->hash_secret)) { - int ret = read(dev_random, - (uint8_t *)&c->hash_secret + random_read, - sizeof(c->hash_secret) - random_read); - - if (ret == -1 && errno == EINTR) - continue; - - if (ret <= 0) - break; - - random_read += ret; - } - if (dev_random >= 0) - close(dev_random); - - if (random_read < sizeof(c->hash_secret)) -#else - if (getrandom(&c->hash_secret, sizeof(c->hash_secret), - GRND_RANDOM) < 0) -#endif /* !HAS_GETRANDOM */ - die_perror("Failed to get random bytes for hash table and TCP"); + raw_random(&c->hash_secret, sizeof(c->hash_secret)); } /** @@ -34,6 +34,9 @@ #include "passt.h" #include "packet.h" #include "log.h" +#ifdef HAS_GETRANDOM +#include <sys/random.h> +#endif /** * sock_l4_sa() - Create and bind socket to socket address, add to epoll list @@ -783,3 +786,54 @@ bool snprintf_check(char *str, size_t size, const char *format, ...) return false; } + +#define DEV_RANDOM "/dev/random" + +/** + * raw_random() - Get high quality random bytes + * @buf: Buffer to fill with random bytes + * @buflen: Number of bytes of random data to put in @buf + * + * Assumes that the random data is essential, and will die() if unable to obtain + * it. + */ +void raw_random(void *buf, size_t buflen) +{ + size_t random_read = 0; +#ifndef HAS_GETRANDOM + int fd = open(DEV_RANDOM, O_RDONLY); + + if (fd < 0) + die_perror("Couldn't open %s", DEV_RANDOM); +#endif + + while (random_read < buflen) { + ssize_t ret; + +#ifdef HAS_GETRANDOM + ret = getrandom((char *)buf + random_read, + buflen - random_read, GRND_RANDOM); +#else + ret = read(dev_random, (char *)buf + random_read, + buflen - random_read); +#endif + + if (ret == -1 && errno == EINTR) + continue; + + if (ret < 0) + die_perror("Error on random data source"); + + if (ret == 0) + break; + + random_read += ret; + } + +#ifndef HAS_GETRANDOM + close(dev_random); +#endif + + if (random_read < buflen) + die("Unexpected EOF on random data source"); +} @@ -263,6 +263,8 @@ static inline bool mod_between(unsigned x, unsigned i, unsigned j, unsigned m) /* FPRINTF() intentionally silences cert-err33-c clang-tidy warnings */ #define FPRINTF(f, ...) (void)fprintf(f, __VA_ARGS__) +void raw_random(void *buf, size_t buflen); + /* * Workarounds for https://github.com/llvm/llvm-project/issues/58992 * |