diff options
Diffstat (limited to 'net/mptcp/options.c')
| -rw-r--r-- | net/mptcp/options.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 5ea127bc7f01..1fa8496f3551 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -14,6 +14,7 @@ void mptcp_parse_option(const unsigned char *ptr, int opsize, { struct mptcp_options_received *mp_opt = &opt_rx->mptcp; u8 subtype = *ptr >> 4; + int expected_opsize; u8 version; u8 flags; @@ -64,7 +65,79 @@ void mptcp_parse_option(const unsigned char *ptr, int opsize, case MPTCPOPT_DSS: pr_debug("DSS"); + ptr++; + + flags = (*ptr++) & MPTCP_DSS_FLAG_MASK; + mp_opt->data_fin = (flags & MPTCP_DSS_DATA_FIN) != 0; + mp_opt->dsn64 = (flags & MPTCP_DSS_DSN64) != 0; + mp_opt->use_map = (flags & MPTCP_DSS_HAS_MAP) != 0; + mp_opt->ack64 = (flags & MPTCP_DSS_ACK64) != 0; + mp_opt->use_ack = (flags & MPTCP_DSS_HAS_ACK); + + pr_debug("data_fin=%d dsn64=%d use_map=%d ack64=%d use_ack=%d", + mp_opt->data_fin, mp_opt->dsn64, + mp_opt->use_map, mp_opt->ack64, + mp_opt->use_ack); + + expected_opsize = TCPOLEN_MPTCP_DSS_BASE; + + if (mp_opt->use_ack) { + if (mp_opt->ack64) + expected_opsize += TCPOLEN_MPTCP_DSS_ACK64; + else + expected_opsize += TCPOLEN_MPTCP_DSS_ACK32; + } + + if (mp_opt->use_map) { + if (mp_opt->dsn64) + expected_opsize += TCPOLEN_MPTCP_DSS_MAP64; + else + expected_opsize += TCPOLEN_MPTCP_DSS_MAP32; + } + + /* RFC 6824, Section 3.3: + * If a checksum is present, but its use had + * not been negotiated in the MP_CAPABLE handshake, + * the checksum field MUST be ignored. + */ + if (opsize != expected_opsize && + opsize != expected_opsize + TCPOLEN_MPTCP_DSS_CHECKSUM) + break; + mp_opt->dss = 1; + + if (mp_opt->use_ack) { + if (mp_opt->ack64) { + mp_opt->data_ack = get_unaligned_be64(ptr); + ptr += 8; + } else { + mp_opt->data_ack = get_unaligned_be32(ptr); + ptr += 4; + } + + pr_debug("data_ack=%llu", mp_opt->data_ack); + } + + if (mp_opt->use_map) { + if (mp_opt->dsn64) { + mp_opt->data_seq = get_unaligned_be64(ptr); + ptr += 8; + } else { + mp_opt->data_seq = get_unaligned_be32(ptr); + ptr += 4; + } + + mp_opt->subflow_seq = get_unaligned_be32(ptr); + ptr += 4; + + mp_opt->data_len = get_unaligned_be16(ptr); + ptr += 2; + + pr_debug("data_seq=%llu subflow_seq=%u data_len=%u", + mp_opt->data_seq, mp_opt->subflow_seq, + mp_opt->data_len); + } + break; default: @@ -275,6 +348,40 @@ bool mptcp_synack_options(const struct request_sock *req, unsigned int *size, return false; } +void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb, + struct tcp_options_received *opt_rx) +{ + struct mptcp_options_received *mp_opt; + struct mptcp_ext *mpext; + + mp_opt = &opt_rx->mptcp; + + if (!mp_opt->dss) + return; + + mpext = skb_ext_add(skb, SKB_EXT_MPTCP); + if (!mpext) + return; + + memset(mpext, 0, sizeof(*mpext)); + + if (mp_opt->use_map) { + mpext->data_seq = mp_opt->data_seq; + mpext->subflow_seq = mp_opt->subflow_seq; + mpext->data_len = mp_opt->data_len; + mpext->use_map = 1; + mpext->dsn64 = mp_opt->dsn64; + } + + if (mp_opt->use_ack) { + mpext->data_ack = mp_opt->data_ack; + mpext->use_ack = 1; + mpext->ack64 = mp_opt->ack64; + } + + mpext->data_fin = mp_opt->data_fin; +} + void mptcp_write_options(__be32 *ptr, struct mptcp_out_options *opts) { if ((OPTION_MPTCP_MPC_SYN | |