TT#108551 fix AEAD kernel encryption of small packets

closes #1230

Change-Id: I26cae7b53eed1ff8155d2fa1e1aa5283a9c37d36

daemon/crypto.c

@@ -593,6 +593,9 @@ static int aes_gcm_decrypt_rtp(struct crypto_context *c, struct rtp_header *r, s
 	unsigned char iv[12];
 	int len, plaintext_len;
 
+	if (s->len < 16)
+		return -1;
+
 	memcpy(iv, c->session_salt, 12);
 
 	*(u_int32_t*)(iv+2) ^= r->ssrc;

kernel-module/xt_RTPENGINE.c

@@ -3914,8 +3914,6 @@ static int srtp_encrypt_aes_gcm(struct re_crypto_context *c,
 
 	if (s->session_salt_len != 12)
 		return -EINVAL;
-	if (r->payload_len < 16)
-		return -EINVAL;
 
 	memcpy(iv, c->session_salt, 12);