crypto: drbg - fix drbg_generate return val check

The drbg_generate returns 0 in success case. That means that
drbg_generate_long will always only generate drbg_max_request_bytes at
most. Longer requests will be truncated to drbg_max_request_bytes.

Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Stephan Mueller 2015-04-18 19:35:45 +02:00 committed by Herbert Xu
parent 04a34d4680
commit 082eb10ba9

View File

@ -1442,19 +1442,19 @@ static int drbg_generate_long(struct drbg_state *drbg,
unsigned char *buf, unsigned int buflen,
struct drbg_string *addtl)
{
int len = 0;
unsigned int len = 0;
unsigned int slice = 0;
do {
int tmplen = 0;
int err = 0;
unsigned int chunk = 0;
slice = ((buflen - len) / drbg_max_request_bytes(drbg));
chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
if (0 >= tmplen)
return tmplen;
len += tmplen;
err = drbg_generate(drbg, buf + len, chunk, addtl);
if (0 > err)
return err;
len += chunk;
} while (slice > 0 && (len < buflen));
return len;
return 0;
}
/*