openssl: RAND_pseudo_bytes() returns 0 if bytes are not cryptographically strong

For our purposes with RNG_WEAK this is fine, so accept a zero return value.

diff --git a/src/libstrongswan/plugins/openssl/openssl_rng.c b/src/libstrongswan/plugins/openssl/openssl_rng.c
index 10db6293a31f023950547deaa69e60323ed8ad51..815cf4f0c163e93513645712dd51d355db7e4a67 100644 (file)
--- a/src/libstrongswan/plugins/openssl/openssl_rng.c
+++ b/src/libstrongswan/plugins/openssl/openssl_rng.c
@@ -47,17 +47,14 @@ struct private_openssl_rng_t {
 METHOD(rng_t, get_bytes, bool,
        private_openssl_rng_t *this, size_t bytes, u_int8_t *buffer)
 {
-       u_int32_t ret;
-
-       if (this->quality == RNG_STRONG)
-       {
-               ret = RAND_bytes((char*)buffer, bytes);
-       }
-       else
+       if (this->quality == RNG_WEAK)
        {
-               ret = RAND_pseudo_bytes((char*)buffer, bytes);
+               /* RAND_pseudo_bytes() returns 1 if returned bytes are strong,
+                * 0 if of not. Both is acceptable for RNG_WEAK. */
+               return RAND_pseudo_bytes((char*)buffer, bytes) != -1;
        }
-       return ret == 1;
+       /* A 0 return value is a failure for RAND_bytes() */
+       return RAND_bytes((char*)buffer, bytes) == 1;
 }
 
 METHOD(rng_t, allocate_bytes, bool,