From 79c0949e9a09f6a14a6dd18dc8396029423f9b68 Mon Sep 17 00:00:00 2001 From: Peter Krystad Date: Tue, 21 Jan 2020 16:56:20 -0800 Subject: mptcp: Add key generation and token tree Generate the local keys, IDSN, and token when creating a new socket. Introduce the token tree to track all tokens in use using a radix tree with the MPTCP token itself as the index. Override the rebuild_header callback in inet_connection_sock_af_ops for creating the local key on a new outgoing connection. Override the init_req callback of tcp_request_sock_ops for creating the local key on a new incoming connection. Will be used to obtain the MPTCP parent socket to handle incoming joins. Co-developed-by: Davide Caratti Signed-off-by: Davide Caratti Co-developed-by: Florian Westphal Signed-off-by: Florian Westphal Co-developed-by: Paolo Abeni Signed-off-by: Paolo Abeni Signed-off-by: Peter Krystad Signed-off-by: Christoph Paasch Signed-off-by: David S. Miller --- net/mptcp/crypto.c | 122 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 net/mptcp/crypto.c (limited to 'net/mptcp/crypto.c') diff --git a/net/mptcp/crypto.c b/net/mptcp/crypto.c new file mode 100644 index 000000000000..bbd6d01af211 --- /dev/null +++ b/net/mptcp/crypto.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Multipath TCP cryptographic functions + * Copyright (c) 2017 - 2019, Intel Corporation. + * + * Note: This code is based on mptcp_ctrl.c, mptcp_ipv4.c, and + * mptcp_ipv6 from multipath-tcp.org, authored by: + * + * Sébastien Barré + * Christoph Paasch + * Jaakko Korkeaniemi + * Gregory Detal + * Fabien Duchêne + * Andreas Seelinger + * Lavkesh Lahngir + * Andreas Ripke + * Vlad Dogaru + * Octavian Purdila + * John Ronan + * Catalin Nicutar + * Brandon Heller + */ + +#include +#include +#include + +#include "protocol.h" + +struct sha1_state { + u32 workspace[SHA_WORKSPACE_WORDS]; + u32 digest[SHA_DIGEST_WORDS]; + unsigned int count; +}; + +static void sha1_init(struct sha1_state *state) +{ + sha_init(state->digest); + state->count = 0; +} + +static void sha1_update(struct sha1_state *state, u8 *input) +{ + sha_transform(state->digest, input, state->workspace); + state->count += SHA_MESSAGE_BYTES; +} + +static void sha1_pad_final(struct sha1_state *state, u8 *input, + unsigned int length, __be32 *mptcp_hashed_key) +{ + int i; + + input[length] = 0x80; + memset(&input[length + 1], 0, SHA_MESSAGE_BYTES - length - 9); + put_unaligned_be64((length + state->count) << 3, + &input[SHA_MESSAGE_BYTES - 8]); + + sha_transform(state->digest, input, state->workspace); + for (i = 0; i < SHA_DIGEST_WORDS; ++i) + put_unaligned_be32(state->digest[i], &mptcp_hashed_key[i]); + + memzero_explicit(state->workspace, SHA_WORKSPACE_WORDS << 2); +} + +void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn) +{ + __be32 mptcp_hashed_key[SHA_DIGEST_WORDS]; + u8 input[SHA_MESSAGE_BYTES]; + struct sha1_state state; + + sha1_init(&state); + put_unaligned_be64(key, input); + sha1_pad_final(&state, input, 8, mptcp_hashed_key); + + if (token) + *token = be32_to_cpu(mptcp_hashed_key[0]); + if (idsn) + *idsn = be64_to_cpu(*((__be64 *)&mptcp_hashed_key[3])); +} + +void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u32 nonce1, u32 nonce2, + u32 *hash_out) +{ + u8 input[SHA_MESSAGE_BYTES * 2]; + struct sha1_state state; + u8 key1be[8]; + u8 key2be[8]; + int i; + + put_unaligned_be64(key1, key1be); + put_unaligned_be64(key2, key2be); + + /* Generate key xored with ipad */ + memset(input, 0x36, SHA_MESSAGE_BYTES); + for (i = 0; i < 8; i++) + input[i] ^= key1be[i]; + for (i = 0; i < 8; i++) + input[i + 8] ^= key2be[i]; + + put_unaligned_be32(nonce1, &input[SHA_MESSAGE_BYTES]); + put_unaligned_be32(nonce2, &input[SHA_MESSAGE_BYTES + 4]); + + sha1_init(&state); + sha1_update(&state, input); + + /* emit sha256(K1 || msg) on the second input block, so we can + * reuse 'input' for the last hashing + */ + sha1_pad_final(&state, &input[SHA_MESSAGE_BYTES], 8, + (__force __be32 *)&input[SHA_MESSAGE_BYTES]); + + /* Prepare second part of hmac */ + memset(input, 0x5C, SHA_MESSAGE_BYTES); + for (i = 0; i < 8; i++) + input[i] ^= key1be[i]; + for (i = 0; i < 8; i++) + input[i + 8] ^= key2be[i]; + + sha1_init(&state); + sha1_update(&state, input); + sha1_pad_final(&state, &input[SHA_MESSAGE_BYTES], SHA_DIGEST_WORDS << 2, + (__be32 *)hash_out); +} -- cgit v1.2.3