Commit 481f34ae authored by Herbert Xu's avatar Herbert Xu
Browse files

[CRYPTO] authenc: Fix hash verification 



The previous code incorrectly included the hash in the verification which
also meant that we'd crash and burn when it comes to actually verifying
the hash since we'd go past the end of the SG list.

This patch fixes that by subtracting authsize from cryptlen at the start.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent e236d4a8

crypto/authenc.c

+10 −4
Original line number Diff line number Diff line
@@ -158,7 +158,8 @@ static int crypto_authenc_encrypt(struct aead_request *req) 
	return crypto_authenc_hash(req);

}



static int crypto_authenc_verify(struct aead_request *req)

static int crypto_authenc_verify(struct aead_request *req,

				 unsigned int cryptlen)

{

	struct crypto_aead *authenc = crypto_aead_reqtfm(req);

	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
@@ -170,7 +171,6 @@ static int crypto_authenc_verify(struct aead_request *req) 
	u8 *ohash = aead_request_ctx(req);

	u8 *ihash;

	struct scatterlist *src = req->src;

	unsigned int cryptlen = req->cryptlen;

	unsigned int authsize;

	int err;
@@ -214,16 +214,22 @@ static int crypto_authenc_decrypt(struct aead_request *req) 
	struct crypto_aead *authenc = crypto_aead_reqtfm(req);

	struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);

	struct ablkcipher_request *abreq = aead_request_ctx(req);

	unsigned int cryptlen = req->cryptlen;

	unsigned int authsize = crypto_aead_authsize(authenc);

	int err;



	err = crypto_authenc_verify(req);

	if (cryptlen < authsize)

		return -EINVAL;

	cryptlen -= authsize;



	err = crypto_authenc_verify(req, cryptlen);

	if (err)

		return err;



	ablkcipher_request_set_tfm(abreq, ctx->enc);

	ablkcipher_request_set_callback(abreq, aead_request_flags(req),

					crypto_authenc_decrypt_done, req);

	ablkcipher_request_set_crypt(abreq, req->src, req->dst, req->cryptlen,

	ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen,

				     req->iv);



	return crypto_ablkcipher_decrypt(abreq);

CRA Git | Maintained and supported by SUSTech CRA and CCSE