/*
* Seed PRNG using randomness from file
* Assume file contains at least RANDOM_BYTES_NEEDED 'random' bytes
*/
u32 SeedPRNGfromFile (const u8 *rfile, RANDOM_STRUCT *r)
{
FILE *fp;
u32 n=RANDOM_BYTES_NEEDED;
u32 bytes;
u8 *buffer;
if (r == NULL) return PRNG_NOT_INIT;
if ( (fp = (FILE *)open_input(rfile)) == NULL) {
exit(1);
}
if ( (buffer = (u8 *)malloc(RANDOM_BYTES_NEEDED)) == NULL) {
fprintf(stderr, "error in SeedPRNGfromFile: out of memory.\n");
exit (1);
}
while (GetRandomBytesNeeded (&n, r) > 0) {
if ( (bytes = fread (buffer, 1, n, fp)) < n ) {
if ( ferror(fp) ) {
fprintf(stderr, "error while reading randomness file '%s' : %s\n",
rfile, strerror(errno));
exit (1);
}
if ( feof(fp) ) {
fprintf(stderr,
"error: not enough bytes in file '%s' to seed PRNG.\n", rfile);
fprintf(stderr, "(bytes expected: %d, bytes read: %d).\n",
RANDOM_BYTES_NEEDED, bytes);
exit (1);
}
fprintf(stderr, "error in SeedPRNGfromFile: unkown error\n");
exit (1);
}
RandomUpdate (r, buffer, bytes);
}
/* zeroize sensitive information */
memset (buffer, 0, RANDOM_BYTES_NEEDED);
free (buffer);
fclose(fp);
}
/*lint -e525 -e438*/
int GeneratePublicKey(DH_KEY *params, unsigned char *publicValue, unsigned int pubValueLen)
{
rand_t *rd;
int rv;
time_t seed;
unsigned int bytesNeeded;
unsigned char seedByte[20] = {0};
R_RANDOM_STRUCT randomStruct;
bytesNeeded = pubValueLen;
randomStruct.bytesNeeded = bytesNeeded;
memset ((POINTER)randomStruct.state, 0, sizeof (randomStruct.state));
randomStruct.outputAvailable = 0;
time(&seed);
rd = rand_open();
if (rd == NULL) return -1;
rand_set(rd,&seed,4);
if (rd == NULL) return -1;
while (1)
{
bytesNeeded = randomStruct.bytesNeeded;
if (bytesNeeded == 0)
break;
rand_get(rd,seedByte,16);
if (rd == NULL) return -1;
RandomUpdate(&randomStruct, seedByte, 16);
}
rd = rand_close(rd);
params->priVallen = pubValueLen;
rv = SetupDHAgreement(publicValue,params->privateValue,pubValueLen, params,&randomStruct);
return rv;
}
