diff options
Diffstat (limited to 'src/random-seed.c')
| -rw-r--r-- | src/random-seed.c | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/src/random-seed.c b/src/random-seed.c index b9cafb7cd7..586c69837b 100644 --- a/src/random-seed.c +++ b/src/random-seed.c @@ -28,11 +28,15 @@ #include "log.h" #include "util.h" +#define POOL_SIZE_MIN 512 + int main(int argc, char *argv[]) { int seed_fd = -1, random_fd = -1; int ret = 1; - uint8_t buf[512]; + void* buf; + size_t buf_size = 0; ssize_t r; + FILE *f; if (argc != 2) { log_error("This program requires one argument."); @@ -43,6 +47,20 @@ int main(int argc, char *argv[]) { log_parse_environment(); log_open(); + /* Read pool size, if possible */ + if ((f = fopen("/proc/sys/kernel/random/poolsize", "re"))) { + fscanf(f, "%zu", &buf_size); + fclose(f); + } + + if (buf_size <= POOL_SIZE_MIN) + buf_size = POOL_SIZE_MIN; + + if (!(buf = malloc(buf_size))) { + log_error("Failed to allocate buffer."); + goto finish; + } + /* When we load the seed we read it and write it to the device * and then immediately update the saved seed with new data, * to make sure the next boot gets seeded differently. */ @@ -63,12 +81,12 @@ int main(int argc, char *argv[]) { } } - if ((r = loop_read(seed_fd, buf, sizeof(buf), false)) != sizeof(buf)) + if ((r = loop_read(seed_fd, buf, buf_size, false)) <= 0) log_error("Failed to read seed file: %s", r < 0 ? strerror(errno) : "EOF"); else { lseek(seed_fd, 0, SEEK_SET); - if ((r = loop_write(random_fd, buf, sizeof(buf), false)) != sizeof(buf)) + if ((r = loop_write(random_fd, buf, (size_t) r, false)) <= 0) log_error("Failed to write seed to /dev/random: %s", r < 0 ? strerror(errno) : "short write"); } @@ -94,10 +112,10 @@ int main(int argc, char *argv[]) { fchmod(seed_fd, 0600); fchown(seed_fd, 0, 0); - if ((r = loop_read(random_fd, buf, sizeof(buf), false)) != sizeof(buf)) + if ((r = loop_read(random_fd, buf, buf_size, false)) <= 0) log_error("Failed to read new seed from /dev/urandom: %s", r < 0 ? strerror(errno) : "EOF"); else { - if ((r = loop_write(seed_fd, buf, sizeof(buf), false)) != sizeof(buf)) + if ((r = loop_write(seed_fd, buf, (size_t) r, false)) <= 0) log_error("Failed to write new random seed file: %s", r < 0 ? strerror(errno) : "short write"); } @@ -110,5 +128,7 @@ finish: if (seed_fd >= 0) close_nointr_nofail(seed_fd); + free(buf); + return ret; } |