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_NEW_SYN_RECV = TCP_NEW_SYN_RECV, 47 DCCP_PARTOPEN = TCP_MAX_STATES, 48 DCCP_PASSIVE_CLOSEREQ, /* clients receiving CloseReq */ 49 DCCP_MAX_STATES 50 }; 51 52 enum { 53 DCCPF_OPEN = TCPF_ESTABLISHED, 54 DCCPF_REQUESTING = TCPF_SYN_SENT, 55 DCCPF_LISTEN = TCPF_LISTEN, 56 DCCPF_RESPOND = TCPF_SYN_RECV, 57 DCCPF_ACTIVE_CLOSEREQ = TCPF_FIN_WAIT1, 58 DCCPF_CLOSING = TCPF_CLOSING, 59 DCCPF_TIME_WAIT = TCPF_TIME_WAIT, 60 DCCPF_CLOSED = TCPF_CLOSE, 61 DCCPF_NEW_SYN_RECV = TCPF_NEW_SYN_RECV, 62 DCCPF_PARTOPEN = (1 << DCCP_PARTOPEN), 63 }; 64 65 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb) 66 { 67 return (struct dccp_hdr *)skb_transport_header(skb); 68 } 69 70 static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen) 71 { 72 skb_push(skb, headlen); 73 skb_reset_transport_header(skb); 74 return memset(skb_transport_header(skb), 0, headlen); 75 } 76 77 static inline struct dccp_hdr_ext *dccp_hdrx(const struct dccp_hdr *dh) 78 { 79 return (struct dccp_hdr_ext *)((unsigned char *)dh + sizeof(*dh)); 80 } 81 82 static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh) 83 { 84 return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0); 85 } 86 87 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb) 88 { 89 const struct dccp_hdr *dh = dccp_hdr(skb); 90 return __dccp_basic_hdr_len(dh); 91 } 92 93 static inline __u64 dccp_hdr_seq(const struct dccp_hdr *dh) 94 { 95 __u64 seq_nr = ntohs(dh->dccph_seq); 96 97 if (dh->dccph_x != 0) 98 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(dh)->dccph_seq_low); 99 else 100 seq_nr += (u32)dh->dccph_seq2 << 16; 101 102 return seq_nr; 103 } 104 105 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb) 106 { 107 return (struct dccp_hdr_request *)(skb_transport_header(skb) + 108 dccp_basic_hdr_len(skb)); 109 } 110 111 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb) 112 { 113 return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) + 114 dccp_basic_hdr_len(skb)); 115 } 116 117 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb) 118 { 119 const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb); 120 return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low); 121 } 122 123 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb) 124 { 125 return (struct dccp_hdr_response *)(skb_transport_header(skb) + 126 dccp_basic_hdr_len(skb)); 127 } 128 129 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb) 130 { 131 return (struct dccp_hdr_reset *)(skb_transport_header(skb) + 132 dccp_basic_hdr_len(skb)); 133 } 134 135 static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh) 136 { 137 return __dccp_basic_hdr_len(dh) + 138 dccp_packet_hdr_len(dh->dccph_type); 139 } 140 141 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb) 142 { 143 return __dccp_hdr_len(dccp_hdr(skb)); 144 } 145 146 /** 147 * struct dccp_request_sock - represent DCCP-specific connection request 148 * @dreq_inet_rsk: structure inherited from 149 * @dreq_iss: initial sequence number, sent on the first Response (RFC 4340, 7.1) 150 * @dreq_gss: greatest sequence number sent (for retransmitted Responses) 151 * @dreq_isr: initial sequence number received in the first Request 152 * @dreq_gsr: greatest sequence number received (for retransmitted Request(s)) 153 * @dreq_service: service code present on the Request (there is just one) 154 * @dreq_featneg: feature negotiation options for this connection 155 * The following two fields are analogous to the ones in dccp_sock: 156 * @dreq_timestamp_echo: last received timestamp to echo (13.1) 157 * @dreq_timestamp_echo: the time of receiving the last @dreq_timestamp_echo 158 */ 159 struct dccp_request_sock { 160 struct inet_request_sock dreq_inet_rsk; 161 __u64 dreq_iss; 162 __u64 dreq_gss; 163 __u64 dreq_isr; 164 __u64 dreq_gsr; 165 __be32 dreq_service; 166 struct list_head dreq_featneg; 167 __u32 dreq_timestamp_echo; 168 __u32 dreq_timestamp_time; 169 }; 170 171 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req) 172 { 173 return (struct dccp_request_sock *)req; 174 } 175 176 extern struct inet_timewait_death_row dccp_death_row; 177 178 extern int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, 179 struct sk_buff *skb); 180 181 struct dccp_options_received { 182 u64 dccpor_ndp:48; 183 u32 dccpor_timestamp; 184 u32 dccpor_timestamp_echo; 185 u32 dccpor_elapsed_time; 186 }; 187 188 struct ccid; 189 190 enum dccp_role { 191 DCCP_ROLE_UNDEFINED, 192 DCCP_ROLE_LISTEN, 193 DCCP_ROLE_CLIENT, 194 DCCP_ROLE_SERVER, 195 }; 196 197 struct dccp_service_list { 198 __u32 dccpsl_nr; 199 __be32 dccpsl_list[0]; 200 }; 201 202 #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1) 203 #define DCCP_SERVICE_CODE_IS_ABSENT 0 204 205 static inline bool dccp_list_has_service(const struct dccp_service_list *sl, 206 const __be32 service) 207 { 208 if (likely(sl != NULL)) { 209 u32 i = sl->dccpsl_nr; 210 while (i--) 211 if (sl->dccpsl_list[i] == service) 212 return true; 213 } 214 return false; 215 } 216 217 struct dccp_ackvec; 218 219 /** 220 * struct dccp_sock - DCCP socket state 221 * 222 * @dccps_swl - sequence number window low 223 * @dccps_swh - sequence number window high 224 * @dccps_awl - acknowledgement number window low 225 * @dccps_awh - acknowledgement number window high 226 * @dccps_iss - initial sequence number sent 227 * @dccps_isr - initial sequence number received 228 * @dccps_osr - first OPEN sequence number received 229 * @dccps_gss - greatest sequence number sent 230 * @dccps_gsr - greatest valid sequence number received 231 * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss 232 * @dccps_service - first (passive sock) or unique (active sock) service code 233 * @dccps_service_list - second .. last service code on passive socket 234 * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option 235 * @dccps_timestamp_time - time of receiving latest @dccps_timestamp_echo 236 * @dccps_l_ack_ratio - feature-local Ack Ratio 237 * @dccps_r_ack_ratio - feature-remote Ack Ratio 238 * @dccps_l_seq_win - local Sequence Window (influences ack number validity) 239 * @dccps_r_seq_win - remote Sequence Window (influences seq number validity) 240 * @dccps_pcslen - sender partial checksum coverage (via sockopt) 241 * @dccps_pcrlen - receiver partial checksum coverage (via sockopt) 242 * @dccps_send_ndp_count - local Send NDP Count feature (7.7.2) 243 * @dccps_ndp_count - number of Non Data Packets since last data packet 244 * @dccps_mss_cache - current value of MSS (path MTU minus header sizes) 245 * @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4) 246 * @dccps_featneg - tracks feature-negotiation state (mostly during handshake) 247 * @dccps_hc_rx_ackvec - rx half connection ack vector 248 * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection) 249 * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection) 250 * @dccps_options_received - parsed set of retrieved options 251 * @dccps_qpolicy - TX dequeueing policy, one of %dccp_packet_dequeueing_policy 252 * @dccps_tx_qlen - maximum length of the TX queue 253 * @dccps_role - role of this sock, one of %dccp_role 254 * @dccps_hc_rx_insert_options - receiver wants to add options when acking 255 * @dccps_hc_tx_insert_options - sender wants to add options when sending 256 * @dccps_server_timewait - server holds timewait state on close (RFC 4340, 8.3) 257 * @dccps_sync_scheduled - flag which signals "send out-of-band message soon" 258 * @dccps_xmitlet - tasklet scheduled by the TX CCID to dequeue data packets 259 * @dccps_xmit_timer - used by the TX CCID to delay sending (rate-based pacing) 260 * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs) 261 */ 262 struct dccp_sock { 263 /* inet_connection_sock has to be the first member of dccp_sock */ 264 struct inet_connection_sock dccps_inet_connection; 265 #define dccps_syn_rtt dccps_inet_connection.icsk_ack.lrcvtime 266 __u64 dccps_swl; 267 __u64 dccps_swh; 268 __u64 dccps_awl; 269 __u64 dccps_awh; 270 __u64 dccps_iss; 271 __u64 dccps_isr; 272 __u64 dccps_osr; 273 __u64 dccps_gss; 274 __u64 dccps_gsr; 275 __u64 dccps_gar; 276 __be32 dccps_service; 277 __u32 dccps_mss_cache; 278 struct dccp_service_list *dccps_service_list; 279 __u32 dccps_timestamp_echo; 280 __u32 dccps_timestamp_time; 281 __u16 dccps_l_ack_ratio; 282 __u16 dccps_r_ack_ratio; 283 __u64 dccps_l_seq_win:48; 284 __u64 dccps_r_seq_win:48; 285 __u8 dccps_pcslen:4; 286 __u8 dccps_pcrlen:4; 287 __u8 dccps_send_ndp_count:1; 288 __u64 dccps_ndp_count:48; 289 unsigned long dccps_rate_last; 290 struct list_head dccps_featneg; 291 struct dccp_ackvec *dccps_hc_rx_ackvec; 292 struct ccid *dccps_hc_rx_ccid; 293 struct ccid *dccps_hc_tx_ccid; 294 struct dccp_options_received dccps_options_received; 295 __u8 dccps_qpolicy; 296 __u32 dccps_tx_qlen; 297 enum dccp_role dccps_role:2; 298 __u8 dccps_hc_rx_insert_options:1; 299 __u8 dccps_hc_tx_insert_options:1; 300 __u8 dccps_server_timewait:1; 301 __u8 dccps_sync_scheduled:1; 302 struct tasklet_struct dccps_xmitlet; 303 struct timer_list dccps_xmit_timer; 304 }; 305 306 static inline struct dccp_sock *dccp_sk(const struct sock *sk) 307 { 308 return (struct dccp_sock *)sk; 309 } 310 311 static inline const char *dccp_role(const struct sock *sk) 312 { 313 switch (dccp_sk(sk)->dccps_role) { 314 case DCCP_ROLE_UNDEFINED: return "undefined"; 315 case DCCP_ROLE_LISTEN: return "listen"; 316 case DCCP_ROLE_SERVER: return "server"; 317 case DCCP_ROLE_CLIENT: return "client"; 318 } 319 return NULL; 320 } 321 322 extern void dccp_syn_ack_timeout(const struct request_sock *req); 323 324 #endif /* _LINUX_DCCP_H */ 325