diff options
| -rw-r--r-- | bin/ykfde.c | 22 |
1 files changed, 10 insertions, 12 deletions
diff --git a/bin/ykfde.c b/bin/ykfde.c index e808abe..9cbf01c 100644 --- a/bin/ykfde.c +++ b/bin/ykfde.c @@ -101,7 +101,7 @@ char * ask_secret(const char * text) { } int main(int argc, char **argv) { - unsigned int version = 0, help = 0; + unsigned int version = 0, help = 0, challenge_int[CHALLENGELEN]; char challenge_old[CHALLENGELEN + 1], challenge_new[CHALLENGELEN + 1], response_old[RESPONSELEN], @@ -112,7 +112,6 @@ int main(int argc, char **argv) { char challengefilename[sizeof(CHALLENGEDIR) + 11 /* "/challenge-" */ + 10 /* unsigned int in char */ + 1], challengefiletmpname[sizeof(CHALLENGEDIR) + 11 /* "/challenge-" */ + 10 /* unsigned int in char */ + 7 /* -XXXXXX */ + 1]; int challengefile = 0, challengefiletmp = 0; - unsigned int seed; int i; size_t len; int8_t rc = EXIT_FAILURE; @@ -196,14 +195,8 @@ int main(int argc, char **argv) { if (version > 0 || help > 0) return EXIT_SUCCESS; - /* initialize random seed */ - if (getentropy(&seed, sizeof(unsigned int)) != 0) { - fprintf(stderr, "Initializing random seed failed.\n"); - goto out10; - } - srand(seed); - /* initialize static buffers */ + memset(challenge_int, 0, CHALLENGELEN * sizeof(unsigned int)); memset(challenge_old, 0, CHALLENGELEN + 1); memset(challenge_new, 0, CHALLENGELEN + 1); memset(response_old, 0, RESPONSELEN); @@ -297,9 +290,13 @@ int main(int argc, char **argv) { (new_2nd_factor != NULL && *new_2nd_factor != 0))) fprintf(stderr, "Warning: Processing second factor, but not enabled in config!\n"); - /* get random number and limit to printable ASCII character (32 to 126) */ - for(i = 0; i < CHALLENGELEN; i++) - challenge_new[i] = (rand() % (126 - 32)) + 32; + /* get random number - try random first, fall back to urandom + We generate an array of unsigned int, the use modulo to limit to printable + ASCII characters (32 to 127). */ + if ((len = getrandom(challenge_int, CHALLENGELEN * sizeof(unsigned int), GRND_RANDOM|GRND_NONBLOCK)) != CHALLENGELEN * sizeof(unsigned int)) + getrandom((void *)((size_t)challenge_int + len), CHALLENGELEN * sizeof(unsigned int) - len, 0); + for (i = 0; i < CHALLENGELEN; i++) + challenge_new[i] = (challenge_int[i] % (127 - 32)) + 32; /* these are the filenames for challenge * we need this for reading and writing */ @@ -441,6 +438,7 @@ out20: out10: /* wipe response (cleartext password!) from memory */ /* This is statically allocated and always save to wipe! */ + memset(challenge_int, 0, CHALLENGELEN * sizeof(unsigned int)); memset(challenge_old, 0, CHALLENGELEN + 1); memset(challenge_new, 0, CHALLENGELEN + 1); memset(response_old, 0, RESPONSELEN); |