crypto: bcm - check assoclen for rfc4543/rfc4106

Validated assoclen for RFC4543 which expects an assoclen
of 16 or 20, the same as RFC4106.
Based on seqiv, IPsec ESP and RFC4543/RFC4106 the assoclen is sizeof
IP Header (spi, seq_no, extended seq_no) and IV len. This can be 16 or
20 bytes.

Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/bcm/cipher.c b/drivers/crypto/bcm/cipher.c
index 869602fcfd965a609a8b721bbecebc9a1c1a6711..1c23e452700bc067c878e17d243721fd337f1377 100644 (file)
--- a/drivers/crypto/bcm/cipher.c
+++ b/drivers/crypto/bcm/cipher.c
@@ -2629,6 +2629,19 @@ static int aead_need_fallback(struct aead_request *req)
                return 1;
        }
 
+       /*
+        * RFC4106 and RFC4543 cannot handle the case where AAD is other than
+        * 16 or 20 bytes long. So use fallback in this case.
+        */
+       if (ctx->cipher.mode == CIPHER_MODE_GCM &&
+           ctx->cipher.alg == CIPHER_ALG_AES &&
+           rctx->iv_ctr_len == GCM_RFC4106_IV_SIZE &&
+           req->assoclen != 16 && req->assoclen != 20) {
+               flow_log("RFC4106/RFC4543 needs fallback for assoclen"
+                        " other than 16 or 20 bytes\n");
+               return 1;
+       }
+
        payload_len = req->cryptlen;
        if (spu->spu_type == SPU_TYPE_SPUM)
                payload_len += req->assoclen;