Commit 50a07aa5 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

tls: rx: always allocate max possible aad size for decrypt 



AAD size is either 5 or 13. Really no point complicating
the code for the 8B of difference. This will also let us
turn the chunked up buffer into a sane struct.

Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 2d91ecac

include/net/tls.h

+1 −0
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ 
#define MAX_IV_SIZE			16

#define TLS_TAG_SIZE			16

#define TLS_MAX_REC_SEQ_SIZE		8

#define TLS_MAX_AAD_SIZE		TLS_AAD_SPACE_SIZE



/* For CCM mode, the full 16-bytes of IV is made of '4' fields of given sizes.

 *

net/tls/tls_sw.c

+10 −9
Original line number Diff line number Diff line
@@ -1450,7 +1450,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb, 


	aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);

	mem_size = aead_size + (nsg * sizeof(struct scatterlist));

	mem_size = mem_size + prot->aad_size;

	mem_size = mem_size + TLS_MAX_AAD_SIZE;

	mem_size = mem_size + MAX_IV_SIZE;

	mem_size = mem_size + prot->tail_size;
@@ -1467,7 +1467,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb, 
	sgin = (struct scatterlist *)(mem + aead_size);

	sgout = sgin + n_sgin;

	aad = (u8 *)(sgout + n_sgout);

	iv = aad + prot->aad_size;

	iv = aad + TLS_MAX_AAD_SIZE;

	tail = iv + MAX_IV_SIZE;



	/* For CCM based ciphers, first byte of nonce+iv is a constant */
@@ -2474,13 +2474,6 @@ int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx) 
		goto free_priv;

	}



	/* Sanity-check the sizes for stack allocations. */

	if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE ||

	    rec_seq_size > TLS_MAX_REC_SEQ_SIZE || tag_size != TLS_TAG_SIZE) {

		rc = -EINVAL;

		goto free_priv;

	}



	if (crypto_info->version == TLS_1_3_VERSION) {

		nonce_size = 0;

		prot->aad_size = TLS_HEADER_SIZE;
@@ -2490,6 +2483,14 @@ int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx) 
		prot->tail_size = 0;

	}



	/* Sanity-check the sizes for stack allocations. */

	if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE ||

	    rec_seq_size > TLS_MAX_REC_SEQ_SIZE || tag_size != TLS_TAG_SIZE ||

	    prot->aad_size > TLS_MAX_AAD_SIZE) {

		rc = -EINVAL;

		goto free_priv;

	}



	prot->version = crypto_info->version;

	prot->cipher_type = crypto_info->cipher_type;

	prot->prepend_size = TLS_HEADER_SIZE + nonce_size;