diff options
| -rw-r--r-- | source4/lib/genrand.c | 60 |
1 files changed, 51 insertions, 9 deletions
diff --git a/source4/lib/genrand.c b/source4/lib/genrand.c index a9ab260385..e11f37e0e9 100644 --- a/source4/lib/genrand.c +++ b/source4/lib/genrand.c @@ -24,7 +24,7 @@ #include "system/iconv.h" #include "lib/crypto/crypto.h" -static unsigned char s_box[258]; +static unsigned char hash[258]; static uint32 counter; static BOOL done_reseed = False; @@ -55,14 +55,58 @@ static void get_rand_reseed_data(int *reseed_data) } /**************************************************************** + Setup the seed. +*****************************************************************/ + +static void seed_random_stream(unsigned char *seedval, size_t seedlen) +{ + unsigned char j = 0; + size_t ind; + + for (ind = 0; ind < 256; ind++) + hash[ind] = (unsigned char)ind; + + for( ind = 0; ind < 256; ind++) { + unsigned char tc; + + j += (hash[ind] + seedval[ind%seedlen]); + + tc = hash[ind]; + hash[ind] = hash[j]; + hash[j] = tc; + } + + hash[256] = 0; + hash[257] = 0; +} + +/**************************************************************** Get datasize bytes worth of random data. *****************************************************************/ -static void get_random_stream(uint8_t sbox[258], unsigned char *data, size_t datasize) +static void get_random_stream(unsigned char *data, size_t datasize) { - memset(data, '\0', datasize); - - arcfour_crypt_sbox(s_box, data, datasize); + unsigned char index_i = hash[256]; + unsigned char index_j = hash[257]; + size_t ind; + + for( ind = 0; ind < datasize; ind++) { + unsigned char tc; + unsigned char t; + + index_i++; + index_j += hash[index_i]; + + tc = hash[index_i]; + hash[index_i] = hash[index_j]; + hash[index_j] = tc; + + t = hash[index_i] + hash[index_j]; + data[ind] = hash[t]; + } + + hash[256] = index_i; + hash[257] = index_j; } /**************************************************************** @@ -103,7 +147,6 @@ static void do_filehash(const char *fname, unsigned char *the_hash) static int do_reseed(BOOL use_fd, int fd) { unsigned char seed_inbuf[40]; - DATA_BLOB seed_blob; uint32 v1, v2; struct timeval tval; pid_t mypid; int reseed_data = 0; @@ -144,8 +187,7 @@ static int do_reseed(BOOL use_fd, int fd) seed_inbuf[i] ^= ((char *)(&reseed_data))[i % sizeof(reseed_data)]; } - seed_blob = data_blob_const(seed_inbuf, sizeof(seed_inbuf)); - arcfour_init(s_box, &seed_blob); + seed_random_stream(seed_inbuf, sizeof(seed_inbuf)); return -1; } @@ -189,7 +231,7 @@ void generate_random_buffer(uint8_t *out, int len) while(len > 0) { int copy_len = len > 16 ? 16 : len; - get_random_stream(s_box, md4_buf, sizeof(md4_buf)); + get_random_stream(md4_buf, sizeof(md4_buf)); mdfour(tmp_buf, md4_buf, sizeof(md4_buf)); memcpy(p, tmp_buf, copy_len); p += copy_len; |