Merge branch 'add-chacha20-poly1305-cipher-to-kernel-tls'

Vadim Fedorenko says:

====================
Add CHACHA20-POLY1305 cipher to Kernel TLS

RFC 7905 defines usage of ChaCha20-Poly1305 in TLS connections. This
cipher is widely used nowadays and it's good to have a support for it
in TLS connections in kernel.
====================

Link: https://lore.kernel.org/r/1606231490-653-1-git-send-email-vfedorenko@novek.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 17 insertions, 15 deletions

diff --git a/include/net/tls.h b/include/net/tls.h
index cf1473099453..b2637edc2726 100644
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -211,6 +211,7 @@ union tls_crypto_context {
 	union {
 		struct tls12_crypto_info_aes_gcm_128 aes_gcm_128;
 		struct tls12_crypto_info_aes_gcm_256 aes_gcm_256;
+		struct tls12_crypto_info_chacha20_poly1305 chacha20_poly1305;
 	};
 };
 
@@ -501,32 +502,33 @@ static inline void tls_advance_record_sn(struct sock *sk,
 	if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size))
 		tls_err_abort(sk, EBADMSG);
 
-	if (prot->version != TLS_1_3_VERSION)
-		tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
+	if (prot->version != TLS_1_3_VERSION &&
+	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305)
+		tls_bigint_increment(ctx->iv + prot->salt_size,
 				     prot->iv_size);
 }
 
 static inline void tls_fill_prepend(struct tls_context *ctx,
 			     char *buf,
 			     size_t plaintext_len,
-			     unsigned char record_type,
-			     int version)
+			     unsigned char record_type)
 {
 	struct tls_prot_info *prot = &ctx->prot_info;
 	size_t pkt_len, iv_size = prot->iv_size;
 
 	pkt_len = plaintext_len + prot->tag_size;
-	if (version != TLS_1_3_VERSION) {
+	if (prot->version != TLS_1_3_VERSION &&
+	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305) {
 		pkt_len += iv_size;
 
 		memcpy(buf + TLS_NONCE_OFFSET,
-		       ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size);
+		       ctx->tx.iv + prot->salt_size, iv_size);
 	}
 
 	/* we cover nonce explicit here as well, so buf should be of
 	 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE
 	 */
-	buf[0] = version == TLS_1_3_VERSION ?
+	buf[0] = prot->version == TLS_1_3_VERSION ?
 		   TLS_RECORD_TYPE_DATA : record_type;
 	/* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */
 	buf[1] = TLS_1_2_VERSION_MINOR;
@@ -539,18 +541,17 @@ static inline void tls_fill_prepend(struct tls_context *ctx,
 static inline void tls_make_aad(char *buf,
 				size_t size,
 				char *record_sequence,
-				int record_sequence_size,
 				unsigned char record_type,
-				int version)
+				struct tls_prot_info *prot)
 {
-	if (version != TLS_1_3_VERSION) {
-		memcpy(buf, record_sequence, record_sequence_size);
+	if (prot->version != TLS_1_3_VERSION) {
+		memcpy(buf, record_sequence, prot->rec_seq_size);
 		buf += 8;
 	} else {
-		size += TLS_CIPHER_AES_GCM_128_TAG_SIZE;
+		size += prot->tag_size;
 	}
 
-	buf[0] = version == TLS_1_3_VERSION ?
+	buf[0] = prot->version == TLS_1_3_VERSION ?
 		  TLS_RECORD_TYPE_DATA : record_type;
 	buf[1] = TLS_1_2_VERSION_MAJOR;
 	buf[2] = TLS_1_2_VERSION_MINOR;
@@ -558,11 +559,12 @@ static inline void tls_make_aad(char *buf,
 	buf[4] = size & 0xFF;
 }
 
-static inline void xor_iv_with_seq(int version, char *iv, char *seq)
+static inline void xor_iv_with_seq(struct tls_prot_info *prot, char *iv, char *seq)
 {
 	int i;
 
-	if (version == TLS_1_3_VERSION) {
+	if (prot->version == TLS_1_3_VERSION ||
+	    prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) {
 		for (i = 0; i < 8; i++)
 			iv[i + 4] ^= seq[i];
 	}