From fb99bce7120014307dde57b3d7def6977a9a62a1 Mon Sep 17 00:00:00 2001 From: Dave Watson Date: Wed, 30 Jan 2019 21:58:05 +0000 Subject: net: tls: Support 256 bit keys Wire up support for 256 bit keys from the setsockopt to the crypto framework Signed-off-by: Dave Watson Signed-off-by: David S. Miller --- include/net/tls.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/tls.h b/include/net/tls.h index 4592606e136a..da616db48413 100644 --- a/include/net/tls.h +++ b/include/net/tls.h @@ -206,7 +206,10 @@ struct cipher_context { union tls_crypto_context { struct tls_crypto_info info; - struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; + union { + struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; + struct tls12_crypto_info_aes_gcm_256 aes_gcm_256; + }; }; struct tls_context { -- cgit v1.2.3 From a2ef9b6a22bd22841bde53e52cc50476fb4d1a5d Mon Sep 17 00:00:00 2001 From: Dave Watson Date: Wed, 30 Jan 2019 21:58:12 +0000 Subject: net: tls: Refactor tls aad space size calculation TLS 1.3 has a different AAD size, use a variable in the code to make TLS 1.3 support easy. Signed-off-by: Dave Watson Signed-off-by: David S. Miller --- include/net/tls.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/net') diff --git a/include/net/tls.h b/include/net/tls.h index da616db48413..754b130672f0 100644 --- a/include/net/tls.h +++ b/include/net/tls.h @@ -202,6 +202,7 @@ struct cipher_context { char *iv; u16 rec_seq_size; char *rec_seq; + u16 aad_size; }; union tls_crypto_context { -- cgit v1.2.3 From 130b392c6cd6b2aed1b7eb32253d4920babb4891 Mon Sep 17 00:00:00 2001 From: Dave Watson Date: Wed, 30 Jan 2019 21:58:31 +0000 Subject: net: tls: Add tls 1.3 support TLS 1.3 has minor changes from TLS 1.2 at the record layer. * Header now hardcodes the same version and application content type in the header. * The real content type is appended after the data, before encryption (or after decryption). * The IV is xored with the sequence number, instead of concatinating four bytes of IV with the explicit IV. * Zero-padding: No exlicit length is given, we search backwards from the end of the decrypted data for the first non-zero byte, which is the content type. Currently recv supports reading zero-padding, but there is no way for send to add zero padding. Signed-off-by: Dave Watson Signed-off-by: David S. Miller --- include/net/tls.h | 66 +++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 49 insertions(+), 17 deletions(-) (limited to 'include/net') diff --git a/include/net/tls.h b/include/net/tls.h index 754b130672f0..004bf01ce868 100644 --- a/include/net/tls.h +++ b/include/net/tls.h @@ -119,6 +119,9 @@ struct tls_rec { /* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */ struct scatterlist sg_aead_out[2]; + char content_type; + struct scatterlist sg_content_type; + char aad_space[TLS_AAD_SPACE_SIZE]; u8 iv_data[TLS_CIPHER_AES_GCM_128_IV_SIZE + TLS_CIPHER_AES_GCM_128_SALT_SIZE]; @@ -203,6 +206,7 @@ struct cipher_context { u16 rec_seq_size; char *rec_seq; u16 aad_size; + u16 tail_size; }; union tls_crypto_context { @@ -397,49 +401,77 @@ static inline bool tls_bigint_increment(unsigned char *seq, int len) } static inline void tls_advance_record_sn(struct sock *sk, - struct cipher_context *ctx) + struct cipher_context *ctx, + int version) { if (tls_bigint_increment(ctx->rec_seq, ctx->rec_seq_size)) tls_err_abort(sk, EBADMSG); - tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, - ctx->iv_size); + + if (version != TLS_1_3_VERSION) { + tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, + ctx->iv_size); + } } static inline void tls_fill_prepend(struct tls_context *ctx, char *buf, size_t plaintext_len, - unsigned char record_type) + unsigned char record_type, + int version) { size_t pkt_len, iv_size = ctx->tx.iv_size; - pkt_len = plaintext_len + iv_size + ctx->tx.tag_size; + pkt_len = plaintext_len + ctx->tx.tag_size; + if (version != TLS_1_3_VERSION) { + pkt_len += iv_size; + + memcpy(buf + TLS_NONCE_OFFSET, + ctx->tx.iv + TLS_CIPHER_AES_GCM_128_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] = record_type; - buf[1] = TLS_VERSION_MINOR(ctx->crypto_send.info.version); - buf[2] = TLS_VERSION_MAJOR(ctx->crypto_send.info.version); + buf[0] = 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; + buf[2] = TLS_1_2_VERSION_MAJOR; /* we can use IV for nonce explicit according to spec */ buf[3] = pkt_len >> 8; buf[4] = pkt_len & 0xFF; - memcpy(buf + TLS_NONCE_OFFSET, - ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); } static inline void tls_make_aad(char *buf, size_t size, char *record_sequence, int record_sequence_size, - unsigned char record_type) + unsigned char record_type, + int version) +{ + if (version != TLS_1_3_VERSION) { + memcpy(buf, record_sequence, record_sequence_size); + buf += 8; + } else { + size += TLS_CIPHER_AES_GCM_128_TAG_SIZE; + } + + buf[0] = 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; + buf[3] = size >> 8; + buf[4] = size & 0xFF; +} + +static inline void xor_iv_with_seq(int version, char *iv, char *seq) { - memcpy(buf, record_sequence, record_sequence_size); + int i; - buf[8] = record_type; - buf[9] = TLS_1_2_VERSION_MAJOR; - buf[10] = TLS_1_2_VERSION_MINOR; - buf[11] = size >> 8; - buf[12] = size & 0xFF; + if (version == TLS_1_3_VERSION) { + for (i = 0; i < 8; i++) + iv[i + 4] ^= seq[i]; + } } static inline struct tls_context *tls_get_ctx(const struct sock *sk) -- cgit v1.2.3