forked from Minki/linux
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 <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>
This commit is contained in:
Peter Krystad
David S. Miller
parent
cf7da0d66c
commit
79c0949e9a
@ -1,4 +1,4 @@
|
||||
# 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
|
||||
|
||||
122
net/mptcp/crypto.c
Normal file
122
net/mptcp/crypto.c
Normal file
@ -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 <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);
|
||||
}
|
||||
@ -201,6 +201,7 @@ static void mptcp_close(struct sock *sk, long timeout)
|
||||
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);
|
||||
@ -281,8 +282,10 @@ static struct sock *mptcp_accept(struct sock *sk, int flags, int *err,
|
||||
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);
|
||||
@ -299,6 +302,10 @@ static struct sock *mptcp_accept(struct sock *sk, int flags, int *err,
|
||||
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);
|
||||
@ -331,6 +338,7 @@ void mptcp_finish_connect(struct sock *ssk)
|
||||
*/
|
||||
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)
|
||||
@ -349,6 +357,7 @@ static struct proto mptcp_prot = {
|
||||
.close = mptcp_close,
|
||||
.accept = mptcp_accept,
|
||||
.shutdown = tcp_shutdown,
|
||||
.destroy = mptcp_destroy,
|
||||
.sendmsg = mptcp_sendmsg,
|
||||
.recvmsg = mptcp_recvmsg,
|
||||
.hash = inet_hash,
|
||||
@ -568,6 +577,12 @@ void __init mptcp_init(void)
|
||||
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,
|
||||
@ -583,6 +598,7 @@ int mptcpv6_init(void)
|
||||
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);
|
||||
|
||||
|
||||
@ -7,6 +7,10 @@
|
||||
#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 */
|
||||
@ -42,6 +46,7 @@ struct mptcp_sock {
|
||||
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 */
|
||||
};
|
||||
@ -61,6 +66,8 @@ struct mptcp_subflow_request_sock {
|
||||
backup : 1;
|
||||
u64 local_key;
|
||||
u64 remote_key;
|
||||
u64 idsn;
|
||||
u32 token;
|
||||
};
|
||||
|
||||
static inline struct mptcp_subflow_request_sock *
|
||||
@ -74,6 +81,8 @@ struct mptcp_subflow_context {
|
||||
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 */
|
||||
@ -112,4 +121,27 @@ void mptcp_get_options(const struct sk_buff *skb,
|
||||
|
||||
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 */
|
||||
|
||||
@ -4,6 +4,8 @@
|
||||
* Copyright (c) 2017 - 2019, Intel Corporation.
|
||||
*/
|
||||
|
||||
#define pr_fmt(fmt) "MPTCP: " fmt
|
||||
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/netdevice.h>
|
||||
@ -18,6 +20,33 @@
|
||||
#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)
|
||||
@ -42,7 +71,12 @@ static void subflow_init_req(struct request_sock *req,
|
||||
#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;
|
||||
}
|
||||
}
|
||||
@ -150,16 +184,28 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk,
|
||||
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;
|
||||
@ -224,6 +270,7 @@ int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock)
|
||||
pr_debug("subflow=%p", subflow);
|
||||
|
||||
*new_sock = sf;
|
||||
sock_hold(sk);
|
||||
subflow->conn = sk;
|
||||
|
||||
return 0;
|
||||
@ -286,6 +333,9 @@ static void subflow_ulp_release(struct sock *sk)
|
||||
if (!ctx)
|
||||
return;
|
||||
|
||||
if (ctx->conn)
|
||||
sock_put(ctx->conn);
|
||||
|
||||
kfree_rcu(ctx, rcu);
|
||||
}
|
||||
|
||||
@ -323,6 +373,7 @@ static void subflow_ulp_clone(const struct request_sock *req,
|
||||
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 = {
|
||||
@ -346,6 +397,8 @@ static int subflow_ops_init(struct request_sock_ops *subflow_ops)
|
||||
if (!subflow_ops->slab)
|
||||
return -ENOMEM;
|
||||
|
||||
subflow_ops->destructor = subflow_req_destructor;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -362,6 +415,7 @@ void mptcp_subflow_init(void)
|
||||
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;
|
||||
@ -371,6 +425,7 @@ void mptcp_subflow_init(void)
|
||||
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;
|
||||
|
||||
195
net/mptcp/token.c
Normal file
195
net/mptcp/token.c
Normal file
@ -0,0 +1,195 @@
|
||||
// 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);
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user