diff options
| -rw-r--r-- | include/linux/tcp.h | 18 | ||||
| -rw-r--r-- | include/net/mptcp.h | 18 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 5 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 13 | ||||
| -rw-r--r-- | net/mptcp/Makefile | 2 | ||||
| -rw-r--r-- | net/mptcp/options.c | 97 | ||||
| -rw-r--r-- | net/mptcp/protocol.h | 29 |
7 files changed, 181 insertions, 1 deletions
diff --git a/include/linux/tcp.h b/include/linux/tcp.h index ca6f01531e64..52798ab00394 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -78,6 +78,16 @@ struct tcp_sack_block { #define TCP_SACK_SEEN (1 << 0) /*1 = peer is SACK capable, */ #define TCP_DSACK_SEEN (1 << 2) /*1 = DSACK was received from peer*/ +#if IS_ENABLED(CONFIG_MPTCP) +struct mptcp_options_received { + u64 sndr_key; + u64 rcvr_key; + u8 mp_capable : 1, + mp_join : 1, + dss : 1; +}; +#endif + struct tcp_options_received { /* PAWS/RTTM data */ int ts_recent_stamp;/* Time we stored ts_recent (for aging) */ @@ -95,6 +105,9 @@ struct tcp_options_received { u8 num_sacks; /* Number of SACK blocks */ u16 user_mss; /* mss requested by user in ioctl */ u16 mss_clamp; /* Maximal mss, negotiated at connection setup */ +#if IS_ENABLED(CONFIG_MPTCP) + struct mptcp_options_received mptcp; +#endif }; static inline void tcp_clear_options(struct tcp_options_received *rx_opt) @@ -104,6 +117,11 @@ static inline void tcp_clear_options(struct tcp_options_received *rx_opt) #if IS_ENABLED(CONFIG_SMC) rx_opt->smc_ok = 0; #endif +#if IS_ENABLED(CONFIG_MPTCP) + rx_opt->mptcp.mp_capable = 0; + rx_opt->mptcp.mp_join = 0; + rx_opt->mptcp.dss = 0; +#endif } /* This is the max number of SACKS that we'll generate and process. It's safe diff --git a/include/net/mptcp.h b/include/net/mptcp.h index 98ba22379117..3daec2ceb3ff 100644 --- a/include/net/mptcp.h +++ b/include/net/mptcp.h @@ -9,6 +9,7 @@ #define __NET_MPTCP_H #include <linux/skbuff.h> +#include <linux/tcp.h> #include <linux/types.h> /* MPTCP sk_buff extension data */ @@ -26,10 +27,22 @@ struct mptcp_ext { /* one byte hole */ }; +struct mptcp_out_options { +#if IS_ENABLED(CONFIG_MPTCP) + u16 suboptions; + u64 sndr_key; + u64 rcvr_key; +#endif +}; + #ifdef CONFIG_MPTCP void mptcp_init(void); +void mptcp_parse_option(const unsigned char *ptr, int opsize, + struct tcp_options_received *opt_rx); +void mptcp_write_options(__be32 *ptr, struct mptcp_out_options *opts); + /* move the skb extension owership, with the assumption that 'to' is * newly allocated */ @@ -76,6 +89,11 @@ static inline void mptcp_init(void) { } +static inline void mptcp_parse_option(const unsigned char *ptr, int opsize, + struct tcp_options_received *opt_rx) +{ +} + static inline void mptcp_skb_ext_move(struct sk_buff *to, const struct sk_buff *from) { diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 358365598216..3458ee13e6f0 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -79,6 +79,7 @@ #include <trace/events/tcp.h> #include <linux/jump_label_ratelimit.h> #include <net/busy_poll.h> +#include <net/mptcp.h> int sysctl_tcp_max_orphans __read_mostly = NR_FILE; @@ -3924,6 +3925,10 @@ void tcp_parse_options(const struct net *net, */ break; #endif + case TCPOPT_MPTCP: + mptcp_parse_option(ptr, opsize, opt_rx); + break; + case TCPOPT_FASTOPEN: tcp_parse_fastopen_option( opsize - TCPOLEN_FASTOPEN_BASE, diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 786978cb2db7..0f0984f39f67 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -38,6 +38,7 @@ #define pr_fmt(fmt) "TCP: " fmt #include <net/tcp.h> +#include <net/mptcp.h> #include <linux/compiler.h> #include <linux/gfp.h> @@ -414,6 +415,7 @@ static inline bool tcp_urg_mode(const struct tcp_sock *tp) #define OPTION_WSCALE (1 << 3) #define OPTION_FAST_OPEN_COOKIE (1 << 8) #define OPTION_SMC (1 << 9) +#define OPTION_MPTCP (1 << 10) static void smc_options_write(__be32 *ptr, u16 *options) { @@ -439,8 +441,17 @@ struct tcp_out_options { __u8 *hash_location; /* temporary pointer, overloaded */ __u32 tsval, tsecr; /* need to include OPTION_TS */ struct tcp_fastopen_cookie *fastopen_cookie; /* Fast open cookie */ + struct mptcp_out_options mptcp; }; +static void mptcp_options_write(__be32 *ptr, struct tcp_out_options *opts) +{ +#if IS_ENABLED(CONFIG_MPTCP) + if (unlikely(OPTION_MPTCP & opts->options)) + mptcp_write_options(ptr, &opts->mptcp); +#endif +} + /* Write previously computed TCP options to the packet. * * Beware: Something in the Internet is very sensitive to the ordering of @@ -549,6 +560,8 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp, } smc_options_write(ptr, &options); + + mptcp_options_write(ptr, opts); } static void smc_set_option(const struct tcp_sock *tp, diff --git a/net/mptcp/Makefile b/net/mptcp/Makefile index 659129d1fcbf..27a846263f08 100644 --- a/net/mptcp/Makefile +++ b/net/mptcp/Makefile @@ -1,4 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_MPTCP) += mptcp.o -mptcp-y := protocol.o +mptcp-y := protocol.o options.o diff --git a/net/mptcp/options.c b/net/mptcp/options.c new file mode 100644 index 000000000000..b7a31c0e5283 --- /dev/null +++ b/net/mptcp/options.c @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Multipath TCP + * + * Copyright (c) 2017 - 2019, Intel Corporation. + */ + +#include <linux/kernel.h> +#include <net/tcp.h> +#include <net/mptcp.h> +#include "protocol.h" + +void mptcp_parse_option(const unsigned char *ptr, int opsize, + struct tcp_options_received *opt_rx) +{ + struct mptcp_options_received *mp_opt = &opt_rx->mptcp; + u8 subtype = *ptr >> 4; + u8 version; + u8 flags; + + switch (subtype) { + case MPTCPOPT_MP_CAPABLE: + if (opsize != TCPOLEN_MPTCP_MPC_SYN && + opsize != TCPOLEN_MPTCP_MPC_ACK) + break; + + version = *ptr++ & MPTCP_VERSION_MASK; + if (version != MPTCP_SUPPORTED_VERSION) + break; + + flags = *ptr++; + if (!((flags & MPTCP_CAP_FLAG_MASK) == MPTCP_CAP_HMAC_SHA1) || + (flags & MPTCP_CAP_EXTENSIBILITY)) + break; + + /* RFC 6824, Section 3.1: + * "For the Checksum Required bit (labeled "A"), if either + * host requires the use of checksums, checksums MUST be used. + * In other words, the only way for checksums not to be used + * is if both hosts in their SYNs set A=0." + * + * Section 3.3.0: + * "If a checksum is not present when its use has been + * negotiated, the receiver MUST close the subflow with a RST as + * it is considered broken." + * + * We don't implement DSS checksum - fall back to TCP. + */ + if (flags & MPTCP_CAP_CHECKSUM_REQD) + break; + + mp_opt->mp_capable = 1; + mp_opt->sndr_key = get_unaligned_be64(ptr); + ptr += 8; + + if (opsize == TCPOLEN_MPTCP_MPC_ACK) { + mp_opt->rcvr_key = get_unaligned_be64(ptr); + ptr += 8; + pr_debug("MP_CAPABLE sndr=%llu, rcvr=%llu", + mp_opt->sndr_key, mp_opt->rcvr_key); + } else { + pr_debug("MP_CAPABLE sndr=%llu", mp_opt->sndr_key); + } + break; + + case MPTCPOPT_DSS: + pr_debug("DSS"); + mp_opt->dss = 1; + break; + + default: + break; + } +} + +void mptcp_write_options(__be32 *ptr, struct mptcp_out_options *opts) +{ + if ((OPTION_MPTCP_MPC_SYN | + OPTION_MPTCP_MPC_ACK) & opts->suboptions) { + u8 len; + + if (OPTION_MPTCP_MPC_SYN & opts->suboptions) + len = TCPOLEN_MPTCP_MPC_SYN; + else + len = TCPOLEN_MPTCP_MPC_ACK; + + *ptr++ = htonl((TCPOPT_MPTCP << 24) | (len << 16) | + (MPTCPOPT_MP_CAPABLE << 12) | + (MPTCP_SUPPORTED_VERSION << 8) | + MPTCP_CAP_HMAC_SHA1); + put_unaligned_be64(opts->sndr_key, ptr); + ptr += 2; + if (OPTION_MPTCP_MPC_ACK & opts->suboptions) { + put_unaligned_be64(opts->rcvr_key, ptr); + ptr += 2; + } + } +} diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index ee04a01bffd3..c59cf8b220b0 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -7,6 +7,35 @@ #ifndef __MPTCP_PROTOCOL_H #define __MPTCP_PROTOCOL_H +#define MPTCP_SUPPORTED_VERSION 0 + +/* MPTCP option bits */ +#define OPTION_MPTCP_MPC_SYN BIT(0) +#define OPTION_MPTCP_MPC_SYNACK BIT(1) +#define OPTION_MPTCP_MPC_ACK BIT(2) + +/* MPTCP option subtypes */ +#define MPTCPOPT_MP_CAPABLE 0 +#define MPTCPOPT_MP_JOIN 1 +#define MPTCPOPT_DSS 2 +#define MPTCPOPT_ADD_ADDR 3 +#define MPTCPOPT_RM_ADDR 4 +#define MPTCPOPT_MP_PRIO 5 +#define MPTCPOPT_MP_FAIL 6 +#define MPTCPOPT_MP_FASTCLOSE 7 + +/* MPTCP suboption lengths */ +#define TCPOLEN_MPTCP_MPC_SYN 12 +#define TCPOLEN_MPTCP_MPC_SYNACK 12 +#define TCPOLEN_MPTCP_MPC_ACK 20 + +/* MPTCP MP_CAPABLE flags */ +#define MPTCP_VERSION_MASK (0x0F) +#define MPTCP_CAP_CHECKSUM_REQD BIT(7) +#define MPTCP_CAP_EXTENSIBILITY BIT(6) +#define MPTCP_CAP_HMAC_SHA1 BIT(0) +#define MPTCP_CAP_FLAG_MASK (0x3F) + /* MPTCP connection sock */ struct mptcp_sock { /* inet_connection_sock must be the first member */ |