From a6acbe62353834dc1913d96e1ace140bc9aafca3 Mon Sep 17 00:00:00 2001 From: Vadim Fedorenko Date: Tue, 24 Nov 2020 18:24:48 +0300 Subject: [PATCH] net/tls: add CHACHA20-POLY1305 specific behavior RFC 7905 defines special behavior for ChaCha-Poly TLS sessions. The differences are in the calculation of nonce and the absence of explicit IV. This behavior is like TLSv1.3 partly. Signed-off-by: Vadim Fedorenko Signed-off-by: Jakub Kicinski --- include/net/tls.h | 9 ++++++--- net/tls/tls_sw.c | 6 ++++-- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/include/net/tls.h b/include/net/tls.h index e4e9c2a..b2637ed 100644 --- a/include/net/tls.h +++ b/include/net/tls.h @@ -502,7 +502,8 @@ 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) + 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); } @@ -516,7 +517,8 @@ static inline void tls_fill_prepend(struct tls_context *ctx, size_t pkt_len, iv_size = prot->iv_size; pkt_len = plaintext_len + prot->tag_size; - if (prot->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, @@ -561,7 +563,8 @@ static inline void xor_iv_with_seq(struct tls_prot_info *prot, char *iv, char *s { int i; - if (prot->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]; } diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 6bc757a..b4eefdb 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1464,7 +1464,8 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb, kfree(mem); return err; } - if (prot->version == TLS_1_3_VERSION) + if (prot->version == TLS_1_3_VERSION || + prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) memcpy(iv + iv_offset, tls_ctx->rx.iv, crypto_aead_ivsize(ctx->aead_recv)); else @@ -2068,7 +2069,8 @@ static int tls_read_size(struct strparser *strp, struct sk_buff *skb) data_len = ((header[4] & 0xFF) | (header[3] << 8)); cipher_overhead = prot->tag_size; - if (prot->version != TLS_1_3_VERSION) + if (prot->version != TLS_1_3_VERSION && + prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305) cipher_overhead += prot->iv_size; if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead + -- 2.7.4