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 <dcaratti@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Co-developed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com>
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_MPTCP) += mptcp.o
-mptcp-y := protocol.o subflow.o options.o
+mptcp-y := protocol.o subflow.o options.o token.o crypto.o
--- /dev/null
+// 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 <sebastien.barre@uclouvain.be>
+ * Christoph Paasch <christoph.paasch@uclouvain.be>
+ * Jaakko Korkeaniemi <jaakko.korkeaniemi@aalto.fi>
+ * Gregory Detal <gregory.detal@uclouvain.be>
+ * Fabien Duchêne <fabien.duchene@uclouvain.be>
+ * Andreas Seelinger <Andreas.Seelinger@rwth-aachen.de>
+ * Lavkesh Lahngir <lavkesh51@gmail.com>
+ * Andreas Ripke <ripke@neclab.eu>
+ * Vlad Dogaru <vlad.dogaru@intel.com>
+ * Octavian Purdila <octavian.purdila@intel.com>
+ * John Ronan <jronan@tssg.org>
+ * Catalin Nicutar <catalin.nicutar@gmail.com>
+ * Brandon Heller <brandonh@stanford.edu>
+ */
+
+#include <linux/kernel.h>
+#include <linux/cryptohash.h>
+#include <asm/unaligned.h>
+
+#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);
+}
struct mptcp_subflow_context *subflow, *tmp;
struct mptcp_sock *msk = mptcp_sk(sk);
+ mptcp_token_destroy(msk->token);
inet_sk_state_store(sk, TCP_CLOSE);
lock_sock(sk);
msk = mptcp_sk(new_mptcp_sock);
msk->remote_key = subflow->remote_key;
msk->local_key = subflow->local_key;
+ msk->token = subflow->token;
msk->subflow = NULL;
+ mptcp_token_update_accept(newsk, new_mptcp_sock);
newsk = new_mptcp_sock;
mptcp_copy_inaddrs(newsk, ssk);
list_add(&subflow->node, &msk->conn_list);
return newsk;
}
+static void mptcp_destroy(struct sock *sk)
+{
+}
+
static int mptcp_get_port(struct sock *sk, unsigned short snum)
{
struct mptcp_sock *msk = mptcp_sk(sk);
*/
WRITE_ONCE(msk->remote_key, subflow->remote_key);
WRITE_ONCE(msk->local_key, subflow->local_key);
+ WRITE_ONCE(msk->token, subflow->token);
}
static void mptcp_sock_graft(struct sock *sk, struct socket *parent)
.close = mptcp_close,
.accept = mptcp_accept,
.shutdown = tcp_shutdown,
+ .destroy = mptcp_destroy,
.sendmsg = mptcp_sendmsg,
.recvmsg = mptcp_recvmsg,
.hash = inet_hash,
static struct proto_ops mptcp_v6_stream_ops;
static struct proto mptcp_v6_prot;
+static void mptcp_v6_destroy(struct sock *sk)
+{
+ mptcp_destroy(sk);
+ inet6_destroy_sock(sk);
+}
+
static struct inet_protosw mptcp_v6_protosw = {
.type = SOCK_STREAM,
.protocol = IPPROTO_MPTCP,
mptcp_v6_prot = mptcp_prot;
strcpy(mptcp_v6_prot.name, "MPTCPv6");
mptcp_v6_prot.slab = NULL;
+ mptcp_v6_prot.destroy = mptcp_v6_destroy;
mptcp_v6_prot.obj_size = sizeof(struct mptcp_sock) +
sizeof(struct ipv6_pinfo);
#ifndef __MPTCP_PROTOCOL_H
#define __MPTCP_PROTOCOL_H
+#include <linux/random.h>
+#include <net/tcp.h>
+#include <net/inet_connection_sock.h>
+
#define MPTCP_SUPPORTED_VERSION 0
/* MPTCP option bits */
struct inet_connection_sock sk;
u64 local_key;
u64 remote_key;
+ u32 token;
struct list_head conn_list;
struct socket *subflow; /* outgoing connect/listener/!mp_capable */
};
backup : 1;
u64 local_key;
u64 remote_key;
+ u64 idsn;
+ u32 token;
};
static inline struct mptcp_subflow_request_sock *
struct list_head node;/* conn_list of subflows */
u64 local_key;
u64 remote_key;
+ u64 idsn;
+ u32 token;
u32 request_mptcp : 1, /* send MP_CAPABLE */
mp_capable : 1, /* remote is MPTCP capable */
fourth_ack : 1, /* send initial DSS */
void mptcp_finish_connect(struct sock *sk);
+int mptcp_token_new_request(struct request_sock *req);
+void mptcp_token_destroy_request(u32 token);
+int mptcp_token_new_connect(struct sock *sk);
+int mptcp_token_new_accept(u32 token);
+void mptcp_token_update_accept(struct sock *sk, struct sock *conn);
+void mptcp_token_destroy(u32 token);
+
+void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
+static inline void mptcp_crypto_key_gen_sha(u64 *key, u32 *token, u64 *idsn)
+{
+ /* we might consider a faster version that computes the key as a
+ * hash of some information available in the MPTCP socket. Use
+ * random data at the moment, as it's probably the safest option
+ * in case multiple sockets are opened in different namespaces at
+ * the same time.
+ */
+ get_random_bytes(key, sizeof(u64));
+ mptcp_crypto_key_sha(*key, token, idsn);
+}
+
+void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u32 nonce1, u32 nonce2,
+ u32 *hash_out);
+
#endif /* __MPTCP_PROTOCOL_H */
* Copyright (c) 2017 - 2019, Intel Corporation.
*/
+#define pr_fmt(fmt) "MPTCP: " fmt
+
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <net/mptcp.h>
#include "protocol.h"
+static int subflow_rebuild_header(struct sock *sk)
+{
+ struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
+ int err = 0;
+
+ if (subflow->request_mptcp && !subflow->token) {
+ pr_debug("subflow=%p", sk);
+ err = mptcp_token_new_connect(sk);
+ }
+
+ if (err)
+ return err;
+
+ return subflow->icsk_af_ops->rebuild_header(sk);
+}
+
+static void subflow_req_destructor(struct request_sock *req)
+{
+ struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req);
+
+ pr_debug("subflow_req=%p", subflow_req);
+
+ if (subflow_req->mp_capable)
+ mptcp_token_destroy_request(subflow_req->token);
+ tcp_request_sock_ops.destructor(req);
+}
+
static void subflow_init_req(struct request_sock *req,
const struct sock *sk_listener,
struct sk_buff *skb)
#endif
if (rx_opt.mptcp.mp_capable && listener->request_mptcp) {
- subflow_req->mp_capable = 1;
+ int err;
+
+ err = mptcp_token_new_request(req);
+ if (err == 0)
+ subflow_req->mp_capable = 1;
+
subflow_req->remote_key = rx_opt.mptcp.sndr_key;
}
}
req_unhash, own_req);
if (child && *own_req) {
- if (!mptcp_subflow_ctx(child)) {
- pr_debug("Closing child socket");
- inet_sk_set_state(child, TCP_CLOSE);
- sock_set_flag(child, SOCK_DEAD);
- inet_csk_destroy_sock(child);
- child = NULL;
+ struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(child);
+
+ /* we have null ctx on TCP fallback, not fatal on MPC
+ * handshake
+ */
+ if (!ctx)
+ return child;
+
+ if (ctx->mp_capable) {
+ if (mptcp_token_new_accept(ctx->token))
+ goto close_child;
}
}
return child;
+
+close_child:
+ pr_debug("closing child socket");
+ tcp_send_active_reset(child, GFP_ATOMIC);
+ inet_csk_prepare_forced_close(child);
+ tcp_done(child);
+ return NULL;
}
static struct inet_connection_sock_af_ops subflow_specific;
pr_debug("subflow=%p", subflow);
*new_sock = sf;
+ sock_hold(sk);
subflow->conn = sk;
return 0;
if (!ctx)
return;
+ if (ctx->conn)
+ sock_put(ctx->conn);
+
kfree_rcu(ctx, rcu);
}
new_ctx->fourth_ack = 1;
new_ctx->remote_key = subflow_req->remote_key;
new_ctx->local_key = subflow_req->local_key;
+ new_ctx->token = subflow_req->token;
}
static struct tcp_ulp_ops subflow_ulp_ops __read_mostly = {
if (!subflow_ops->slab)
return -ENOMEM;
+ subflow_ops->destructor = subflow_req_destructor;
+
return 0;
}
subflow_specific.conn_request = subflow_v4_conn_request;
subflow_specific.syn_recv_sock = subflow_syn_recv_sock;
subflow_specific.sk_rx_dst_set = subflow_finish_connect;
+ subflow_specific.rebuild_header = subflow_rebuild_header;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
subflow_request_sock_ipv6_ops = tcp_request_sock_ipv6_ops;
subflow_v6_specific.conn_request = subflow_v6_conn_request;
subflow_v6_specific.syn_recv_sock = subflow_syn_recv_sock;
subflow_v6_specific.sk_rx_dst_set = subflow_finish_connect;
+ subflow_v6_specific.rebuild_header = subflow_rebuild_header;
subflow_v6m_specific = subflow_v6_specific;
subflow_v6m_specific.queue_xmit = ipv4_specific.queue_xmit;
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/* Multipath TCP token management
+ * Copyright (c) 2017 - 2019, Intel Corporation.
+ *
+ * Note: This code is based on mptcp_ctrl.c from multipath-tcp.org,
+ * authored by:
+ *
+ * Sébastien Barré <sebastien.barre@uclouvain.be>
+ * Christoph Paasch <christoph.paasch@uclouvain.be>
+ * Jaakko Korkeaniemi <jaakko.korkeaniemi@aalto.fi>
+ * Gregory Detal <gregory.detal@uclouvain.be>
+ * Fabien Duchêne <fabien.duchene@uclouvain.be>
+ * Andreas Seelinger <Andreas.Seelinger@rwth-aachen.de>
+ * Lavkesh Lahngir <lavkesh51@gmail.com>
+ * Andreas Ripke <ripke@neclab.eu>
+ * Vlad Dogaru <vlad.dogaru@intel.com>
+ * Octavian Purdila <octavian.purdila@intel.com>
+ * John Ronan <jronan@tssg.org>
+ * Catalin Nicutar <catalin.nicutar@gmail.com>
+ * Brandon Heller <brandonh@stanford.edu>
+ */
+
+#define pr_fmt(fmt) "MPTCP: " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/radix-tree.h>
+#include <linux/ip.h>
+#include <linux/tcp.h>
+#include <net/sock.h>
+#include <net/inet_common.h>
+#include <net/protocol.h>
+#include <net/mptcp.h>
+#include "protocol.h"
+
+static RADIX_TREE(token_tree, GFP_ATOMIC);
+static RADIX_TREE(token_req_tree, GFP_ATOMIC);
+static DEFINE_SPINLOCK(token_tree_lock);
+static int token_used __read_mostly;
+
+/**
+ * mptcp_token_new_request - create new key/idsn/token for subflow_request
+ * @req - the request socket
+ *
+ * This function is called when a new mptcp connection is coming in.
+ *
+ * It creates a unique token to identify the new mptcp connection,
+ * a secret local key and the initial data sequence number (idsn).
+ *
+ * Returns 0 on success.
+ */
+int mptcp_token_new_request(struct request_sock *req)
+{
+ struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req);
+ int err;
+
+ while (1) {
+ u32 token;
+
+ mptcp_crypto_key_gen_sha(&subflow_req->local_key,
+ &subflow_req->token,
+ &subflow_req->idsn);
+ pr_debug("req=%p local_key=%llu, token=%u, idsn=%llu\n",
+ req, subflow_req->local_key, subflow_req->token,
+ subflow_req->idsn);
+
+ token = subflow_req->token;
+ spin_lock_bh(&token_tree_lock);
+ if (!radix_tree_lookup(&token_req_tree, token) &&
+ !radix_tree_lookup(&token_tree, token))
+ break;
+ spin_unlock_bh(&token_tree_lock);
+ }
+
+ err = radix_tree_insert(&token_req_tree,
+ subflow_req->token, &token_used);
+ spin_unlock_bh(&token_tree_lock);
+ return err;
+}
+
+/**
+ * mptcp_token_new_connect - create new key/idsn/token for subflow
+ * @sk - the socket that will initiate a connection
+ *
+ * This function is called when a new outgoing mptcp connection is
+ * initiated.
+ *
+ * It creates a unique token to identify the new mptcp connection,
+ * a secret local key and the initial data sequence number (idsn).
+ *
+ * On success, the mptcp connection can be found again using
+ * the computed token at a later time, this is needed to process
+ * join requests.
+ *
+ * returns 0 on success.
+ */
+int mptcp_token_new_connect(struct sock *sk)
+{
+ struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
+ struct sock *mptcp_sock = subflow->conn;
+ int err;
+
+ while (1) {
+ u32 token;
+
+ mptcp_crypto_key_gen_sha(&subflow->local_key, &subflow->token,
+ &subflow->idsn);
+
+ pr_debug("ssk=%p, local_key=%llu, token=%u, idsn=%llu\n",
+ sk, subflow->local_key, subflow->token, subflow->idsn);
+
+ token = subflow->token;
+ spin_lock_bh(&token_tree_lock);
+ if (!radix_tree_lookup(&token_req_tree, token) &&
+ !radix_tree_lookup(&token_tree, token))
+ break;
+ spin_unlock_bh(&token_tree_lock);
+ }
+ err = radix_tree_insert(&token_tree, subflow->token, mptcp_sock);
+ spin_unlock_bh(&token_tree_lock);
+
+ return err;
+}
+
+/**
+ * mptcp_token_new_accept - insert token for later processing
+ * @token: the token to insert to the tree
+ *
+ * Called when a SYN packet creates a new logical connection, i.e.
+ * is not a join request.
+ *
+ * We don't have an mptcp socket yet at that point.
+ * This is paired with mptcp_token_update_accept, called on accept().
+ */
+int mptcp_token_new_accept(u32 token)
+{
+ int err;
+
+ spin_lock_bh(&token_tree_lock);
+ err = radix_tree_insert(&token_tree, token, &token_used);
+ spin_unlock_bh(&token_tree_lock);
+
+ return err;
+}
+
+/**
+ * mptcp_token_update_accept - update token to map to mptcp socket
+ * @conn: the new struct mptcp_sock
+ * @sk: the initial subflow for this mptcp socket
+ *
+ * Called when the first mptcp socket is created on accept to
+ * refresh the dummy mapping (done to reserve the token) with
+ * the mptcp_socket structure that wasn't allocated before.
+ */
+void mptcp_token_update_accept(struct sock *sk, struct sock *conn)
+{
+ struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
+ void __rcu **slot;
+
+ spin_lock_bh(&token_tree_lock);
+ slot = radix_tree_lookup_slot(&token_tree, subflow->token);
+ WARN_ON_ONCE(!slot);
+ if (slot) {
+ WARN_ON_ONCE(rcu_access_pointer(*slot) != &token_used);
+ radix_tree_replace_slot(&token_tree, slot, conn);
+ }
+ spin_unlock_bh(&token_tree_lock);
+}
+
+/**
+ * mptcp_token_destroy_request - remove mptcp connection/token
+ * @token - token of mptcp connection to remove
+ *
+ * Remove not-yet-fully-established incoming connection identified
+ * by @token.
+ */
+void mptcp_token_destroy_request(u32 token)
+{
+ spin_lock_bh(&token_tree_lock);
+ radix_tree_delete(&token_req_tree, token);
+ spin_unlock_bh(&token_tree_lock);
+}
+
+/**
+ * mptcp_token_destroy - remove mptcp connection/token
+ * @token - token of mptcp connection to remove
+ *
+ * Remove the connection identified by @token.
+ */
+void mptcp_token_destroy(u32 token)
+{
+ spin_lock_bh(&token_tree_lock);
+ radix_tree_delete(&token_tree, token);
+ spin_unlock_bh(&token_tree_lock);
+}
projects / platform / kernel / linux-starfive.git / commitdiff