| 1 | #ifndef _LINUX_DCCP_H |
| 2 | #define _LINUX_DCCP_H |
| 3 | |
| 4 | |
| 5 | #include <linux/in.h> |
| 6 | #include <linux/interrupt.h> |
| 7 | #include <linux/ktime.h> |
| 8 | #include <linux/list.h> |
| 9 | #include <linux/uio.h> |
| 10 | #include <linux/workqueue.h> |
| 11 | |
| 12 | #include <net/inet_connection_sock.h> |
| 13 | #include <net/inet_sock.h> |
| 14 | #include <net/inet_timewait_sock.h> |
| 15 | #include <net/tcp_states.h> |
| 16 | #include <uapi/linux/dccp.h> |
| 17 | |
| 18 | enum dccp_state { |
| 19 | DCCP_OPEN = TCP_ESTABLISHED, |
| 20 | DCCP_REQUESTING = TCP_SYN_SENT, |
| 21 | DCCP_LISTEN = TCP_LISTEN, |
| 22 | DCCP_RESPOND = TCP_SYN_RECV, |
| 23 | /* |
| 24 | * States involved in closing a DCCP connection: |
| 25 | * 1) ACTIVE_CLOSEREQ is entered by a server sending a CloseReq. |
| 26 | * |
| 27 | * 2) CLOSING can have three different meanings (RFC 4340, 8.3): |
| 28 | * a. Client has performed active-close, has sent a Close to the server |
| 29 | * from state OPEN or PARTOPEN, and is waiting for the final Reset |
| 30 | * (in this case, SOCK_DONE == 1). |
| 31 | * b. Client is asked to perform passive-close, by receiving a CloseReq |
| 32 | * in (PART)OPEN state. It sends a Close and waits for final Reset |
| 33 | * (in this case, SOCK_DONE == 0). |
| 34 | * c. Server performs an active-close as in (a), keeps TIMEWAIT state. |
| 35 | * |
| 36 | * 3) The following intermediate states are employed to give passively |
| 37 | * closing nodes a chance to process their unread data: |
| 38 | * - PASSIVE_CLOSE (from OPEN => CLOSED) and |
| 39 | * - PASSIVE_CLOSEREQ (from (PART)OPEN to CLOSING; case (b) above). |
| 40 | */ |
| 41 | DCCP_ACTIVE_CLOSEREQ = TCP_FIN_WAIT1, |
| 42 | DCCP_PASSIVE_CLOSE = TCP_CLOSE_WAIT, /* any node receiving a Close */ |
| 43 | DCCP_CLOSING = TCP_CLOSING, |
| 44 | DCCP_TIME_WAIT = TCP_TIME_WAIT, |
| 45 | DCCP_CLOSED = TCP_CLOSE, |
| 46 | DCCP_PARTOPEN = TCP_MAX_STATES, |
| 47 | DCCP_PASSIVE_CLOSEREQ, /* clients receiving CloseReq */ |
| 48 | DCCP_MAX_STATES |
| 49 | }; |
| 50 | |
| 51 | enum { |
| 52 | DCCPF_OPEN = TCPF_ESTABLISHED, |
| 53 | DCCPF_REQUESTING = TCPF_SYN_SENT, |
| 54 | DCCPF_LISTEN = TCPF_LISTEN, |
| 55 | DCCPF_RESPOND = TCPF_SYN_RECV, |
| 56 | DCCPF_ACTIVE_CLOSEREQ = TCPF_FIN_WAIT1, |
| 57 | DCCPF_CLOSING = TCPF_CLOSING, |
| 58 | DCCPF_TIME_WAIT = TCPF_TIME_WAIT, |
| 59 | DCCPF_CLOSED = TCPF_CLOSE, |
| 60 | DCCPF_PARTOPEN = (1 << DCCP_PARTOPEN), |
| 61 | }; |
| 62 | |
| 63 | static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb) |
| 64 | { |
| 65 | return (struct dccp_hdr *)skb_transport_header(skb); |
| 66 | } |
| 67 | |
| 68 | static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen) |
| 69 | { |
| 70 | skb_push(skb, headlen); |
| 71 | skb_reset_transport_header(skb); |
| 72 | return memset(skb_transport_header(skb), 0, headlen); |
| 73 | } |
| 74 | |
| 75 | static inline struct dccp_hdr_ext *dccp_hdrx(const struct dccp_hdr *dh) |
| 76 | { |
| 77 | return (struct dccp_hdr_ext *)((unsigned char *)dh + sizeof(*dh)); |
| 78 | } |
| 79 | |
| 80 | static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh) |
| 81 | { |
| 82 | return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0); |
| 83 | } |
| 84 | |
| 85 | static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb) |
| 86 | { |
| 87 | const struct dccp_hdr *dh = dccp_hdr(skb); |
| 88 | return __dccp_basic_hdr_len(dh); |
| 89 | } |
| 90 | |
| 91 | static inline __u64 dccp_hdr_seq(const struct dccp_hdr *dh) |
| 92 | { |
| 93 | __u64 seq_nr = ntohs(dh->dccph_seq); |
| 94 | |
| 95 | if (dh->dccph_x != 0) |
| 96 | seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(dh)->dccph_seq_low); |
| 97 | else |
| 98 | seq_nr += (u32)dh->dccph_seq2 << 16; |
| 99 | |
| 100 | return seq_nr; |
| 101 | } |
| 102 | |
| 103 | static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb) |
| 104 | { |
| 105 | return (struct dccp_hdr_request *)(skb_transport_header(skb) + |
| 106 | dccp_basic_hdr_len(skb)); |
| 107 | } |
| 108 | |
| 109 | static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb) |
| 110 | { |
| 111 | return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) + |
| 112 | dccp_basic_hdr_len(skb)); |
| 113 | } |
| 114 | |
| 115 | static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb) |
| 116 | { |
| 117 | const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb); |
| 118 | return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low); |
| 119 | } |
| 120 | |
| 121 | static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb) |
| 122 | { |
| 123 | return (struct dccp_hdr_response *)(skb_transport_header(skb) + |
| 124 | dccp_basic_hdr_len(skb)); |
| 125 | } |
| 126 | |
| 127 | static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb) |
| 128 | { |
| 129 | return (struct dccp_hdr_reset *)(skb_transport_header(skb) + |
| 130 | dccp_basic_hdr_len(skb)); |
| 131 | } |
| 132 | |
| 133 | static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh) |
| 134 | { |
| 135 | return __dccp_basic_hdr_len(dh) + |
| 136 | dccp_packet_hdr_len(dh->dccph_type); |
| 137 | } |
| 138 | |
| 139 | static inline unsigned int dccp_hdr_len(const struct sk_buff *skb) |
| 140 | { |
| 141 | return __dccp_hdr_len(dccp_hdr(skb)); |
| 142 | } |
| 143 | |
| 144 | /** |
| 145 | * struct dccp_request_sock - represent DCCP-specific connection request |
| 146 | * @dreq_inet_rsk: structure inherited from |
| 147 | * @dreq_iss: initial sequence number, sent on the first Response (RFC 4340, 7.1) |
| 148 | * @dreq_gss: greatest sequence number sent (for retransmitted Responses) |
| 149 | * @dreq_isr: initial sequence number received in the first Request |
| 150 | * @dreq_gsr: greatest sequence number received (for retransmitted Request(s)) |
| 151 | * @dreq_service: service code present on the Request (there is just one) |
| 152 | * @dreq_featneg: feature negotiation options for this connection |
| 153 | * The following two fields are analogous to the ones in dccp_sock: |
| 154 | * @dreq_timestamp_echo: last received timestamp to echo (13.1) |
| 155 | * @dreq_timestamp_echo: the time of receiving the last @dreq_timestamp_echo |
| 156 | */ |
| 157 | struct dccp_request_sock { |
| 158 | struct inet_request_sock dreq_inet_rsk; |
| 159 | __u64 dreq_iss; |
| 160 | __u64 dreq_gss; |
| 161 | __u64 dreq_isr; |
| 162 | __u64 dreq_gsr; |
| 163 | __be32 dreq_service; |
| 164 | struct list_head dreq_featneg; |
| 165 | __u32 dreq_timestamp_echo; |
| 166 | __u32 dreq_timestamp_time; |
| 167 | }; |
| 168 | |
| 169 | static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req) |
| 170 | { |
| 171 | return (struct dccp_request_sock *)req; |
| 172 | } |
| 173 | |
| 174 | extern struct inet_timewait_death_row dccp_death_row; |
| 175 | |
| 176 | extern int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, |
| 177 | struct sk_buff *skb); |
| 178 | |
| 179 | struct dccp_options_received { |
| 180 | u64 dccpor_ndp:48; |
| 181 | u32 dccpor_timestamp; |
| 182 | u32 dccpor_timestamp_echo; |
| 183 | u32 dccpor_elapsed_time; |
| 184 | }; |
| 185 | |
| 186 | struct ccid; |
| 187 | |
| 188 | enum dccp_role { |
| 189 | DCCP_ROLE_UNDEFINED, |
| 190 | DCCP_ROLE_LISTEN, |
| 191 | DCCP_ROLE_CLIENT, |
| 192 | DCCP_ROLE_SERVER, |
| 193 | }; |
| 194 | |
| 195 | struct dccp_service_list { |
| 196 | __u32 dccpsl_nr; |
| 197 | __be32 dccpsl_list[0]; |
| 198 | }; |
| 199 | |
| 200 | #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1) |
| 201 | #define DCCP_SERVICE_CODE_IS_ABSENT 0 |
| 202 | |
| 203 | static inline int dccp_list_has_service(const struct dccp_service_list *sl, |
| 204 | const __be32 service) |
| 205 | { |
| 206 | if (likely(sl != NULL)) { |
| 207 | u32 i = sl->dccpsl_nr; |
| 208 | while (i--) |
| 209 | if (sl->dccpsl_list[i] == service) |
| 210 | return 1; |
| 211 | } |
| 212 | return 0; |
| 213 | } |
| 214 | |
| 215 | struct dccp_ackvec; |
| 216 | |
| 217 | /** |
| 218 | * struct dccp_sock - DCCP socket state |
| 219 | * |
| 220 | * @dccps_swl - sequence number window low |
| 221 | * @dccps_swh - sequence number window high |
| 222 | * @dccps_awl - acknowledgement number window low |
| 223 | * @dccps_awh - acknowledgement number window high |
| 224 | * @dccps_iss - initial sequence number sent |
| 225 | * @dccps_isr - initial sequence number received |
| 226 | * @dccps_osr - first OPEN sequence number received |
| 227 | * @dccps_gss - greatest sequence number sent |
| 228 | * @dccps_gsr - greatest valid sequence number received |
| 229 | * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss |
| 230 | * @dccps_service - first (passive sock) or unique (active sock) service code |
| 231 | * @dccps_service_list - second .. last service code on passive socket |
| 232 | * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option |
| 233 | * @dccps_timestamp_time - time of receiving latest @dccps_timestamp_echo |
| 234 | * @dccps_l_ack_ratio - feature-local Ack Ratio |
| 235 | * @dccps_r_ack_ratio - feature-remote Ack Ratio |
| 236 | * @dccps_l_seq_win - local Sequence Window (influences ack number validity) |
| 237 | * @dccps_r_seq_win - remote Sequence Window (influences seq number validity) |
| 238 | * @dccps_pcslen - sender partial checksum coverage (via sockopt) |
| 239 | * @dccps_pcrlen - receiver partial checksum coverage (via sockopt) |
| 240 | * @dccps_send_ndp_count - local Send NDP Count feature (7.7.2) |
| 241 | * @dccps_ndp_count - number of Non Data Packets since last data packet |
| 242 | * @dccps_mss_cache - current value of MSS (path MTU minus header sizes) |
| 243 | * @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4) |
| 244 | * @dccps_featneg - tracks feature-negotiation state (mostly during handshake) |
| 245 | * @dccps_hc_rx_ackvec - rx half connection ack vector |
| 246 | * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection) |
| 247 | * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection) |
| 248 | * @dccps_options_received - parsed set of retrieved options |
| 249 | * @dccps_qpolicy - TX dequeueing policy, one of %dccp_packet_dequeueing_policy |
| 250 | * @dccps_tx_qlen - maximum length of the TX queue |
| 251 | * @dccps_role - role of this sock, one of %dccp_role |
| 252 | * @dccps_hc_rx_insert_options - receiver wants to add options when acking |
| 253 | * @dccps_hc_tx_insert_options - sender wants to add options when sending |
| 254 | * @dccps_server_timewait - server holds timewait state on close (RFC 4340, 8.3) |
| 255 | * @dccps_sync_scheduled - flag which signals "send out-of-band message soon" |
| 256 | * @dccps_xmitlet - tasklet scheduled by the TX CCID to dequeue data packets |
| 257 | * @dccps_xmit_timer - used by the TX CCID to delay sending (rate-based pacing) |
| 258 | * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs) |
| 259 | */ |
| 260 | struct dccp_sock { |
| 261 | /* inet_connection_sock has to be the first member of dccp_sock */ |
| 262 | struct inet_connection_sock dccps_inet_connection; |
| 263 | #define dccps_syn_rtt dccps_inet_connection.icsk_ack.lrcvtime |
| 264 | __u64 dccps_swl; |
| 265 | __u64 dccps_swh; |
| 266 | __u64 dccps_awl; |
| 267 | __u64 dccps_awh; |
| 268 | __u64 dccps_iss; |
| 269 | __u64 dccps_isr; |
| 270 | __u64 dccps_osr; |
| 271 | __u64 dccps_gss; |
| 272 | __u64 dccps_gsr; |
| 273 | __u64 dccps_gar; |
| 274 | __be32 dccps_service; |
| 275 | __u32 dccps_mss_cache; |
| 276 | struct dccp_service_list *dccps_service_list; |
| 277 | __u32 dccps_timestamp_echo; |
| 278 | __u32 dccps_timestamp_time; |
| 279 | __u16 dccps_l_ack_ratio; |
| 280 | __u16 dccps_r_ack_ratio; |
| 281 | __u64 dccps_l_seq_win:48; |
| 282 | __u64 dccps_r_seq_win:48; |
| 283 | __u8 dccps_pcslen:4; |
| 284 | __u8 dccps_pcrlen:4; |
| 285 | __u8 dccps_send_ndp_count:1; |
| 286 | __u64 dccps_ndp_count:48; |
| 287 | unsigned long dccps_rate_last; |
| 288 | struct list_head dccps_featneg; |
| 289 | struct dccp_ackvec *dccps_hc_rx_ackvec; |
| 290 | struct ccid *dccps_hc_rx_ccid; |
| 291 | struct ccid *dccps_hc_tx_ccid; |
| 292 | struct dccp_options_received dccps_options_received; |
| 293 | __u8 dccps_qpolicy; |
| 294 | __u32 dccps_tx_qlen; |
| 295 | enum dccp_role dccps_role:2; |
| 296 | __u8 dccps_hc_rx_insert_options:1; |
| 297 | __u8 dccps_hc_tx_insert_options:1; |
| 298 | __u8 dccps_server_timewait:1; |
| 299 | __u8 dccps_sync_scheduled:1; |
| 300 | struct tasklet_struct dccps_xmitlet; |
| 301 | struct timer_list dccps_xmit_timer; |
| 302 | }; |
| 303 | |
| 304 | static inline struct dccp_sock *dccp_sk(const struct sock *sk) |
| 305 | { |
| 306 | return (struct dccp_sock *)sk; |
| 307 | } |
| 308 | |
| 309 | static inline const char *dccp_role(const struct sock *sk) |
| 310 | { |
| 311 | switch (dccp_sk(sk)->dccps_role) { |
| 312 | case DCCP_ROLE_UNDEFINED: return "undefined"; |
| 313 | case DCCP_ROLE_LISTEN: return "listen"; |
| 314 | case DCCP_ROLE_SERVER: return "server"; |
| 315 | case DCCP_ROLE_CLIENT: return "client"; |
| 316 | } |
| 317 | return NULL; |
| 318 | } |
| 319 | |
| 320 | extern void dccp_syn_ack_timeout(struct sock *sk, struct request_sock *req); |
| 321 | |
| 322 | #endif /* _LINUX_DCCP_H */ |