dccp.h 11 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef _LINUX_DCCP_H
  3. #define _LINUX_DCCP_H
  4. #include <linux/in.h>
  5. #include <linux/interrupt.h>
  6. #include <linux/ktime.h>
  7. #include <linux/list.h>
  8. #include <linux/uio.h>
  9. #include <linux/workqueue.h>
  10. #include <net/inet_connection_sock.h>
  11. #include <net/inet_sock.h>
  12. #include <net/inet_timewait_sock.h>
  13. #include <net/tcp_states.h>
  14. #include <uapi/linux/dccp.h>
  15. enum dccp_state {
  16. DCCP_OPEN = TCP_ESTABLISHED,
  17. DCCP_REQUESTING = TCP_SYN_SENT,
  18. DCCP_LISTEN = TCP_LISTEN,
  19. DCCP_RESPOND = TCP_SYN_RECV,
  20. /*
  21. * States involved in closing a DCCP connection:
  22. * 1) ACTIVE_CLOSEREQ is entered by a server sending a CloseReq.
  23. *
  24. * 2) CLOSING can have three different meanings (RFC 4340, 8.3):
  25. * a. Client has performed active-close, has sent a Close to the server
  26. * from state OPEN or PARTOPEN, and is waiting for the final Reset
  27. * (in this case, SOCK_DONE == 1).
  28. * b. Client is asked to perform passive-close, by receiving a CloseReq
  29. * in (PART)OPEN state. It sends a Close and waits for final Reset
  30. * (in this case, SOCK_DONE == 0).
  31. * c. Server performs an active-close as in (a), keeps TIMEWAIT state.
  32. *
  33. * 3) The following intermediate states are employed to give passively
  34. * closing nodes a chance to process their unread data:
  35. * - PASSIVE_CLOSE (from OPEN => CLOSED) and
  36. * - PASSIVE_CLOSEREQ (from (PART)OPEN to CLOSING; case (b) above).
  37. */
  38. DCCP_ACTIVE_CLOSEREQ = TCP_FIN_WAIT1,
  39. DCCP_PASSIVE_CLOSE = TCP_CLOSE_WAIT, /* any node receiving a Close */
  40. DCCP_CLOSING = TCP_CLOSING,
  41. DCCP_TIME_WAIT = TCP_TIME_WAIT,
  42. DCCP_CLOSED = TCP_CLOSE,
  43. DCCP_NEW_SYN_RECV = TCP_NEW_SYN_RECV,
  44. DCCP_PARTOPEN = TCP_MAX_STATES,
  45. DCCP_PASSIVE_CLOSEREQ, /* clients receiving CloseReq */
  46. DCCP_MAX_STATES
  47. };
  48. enum {
  49. DCCPF_OPEN = TCPF_ESTABLISHED,
  50. DCCPF_REQUESTING = TCPF_SYN_SENT,
  51. DCCPF_LISTEN = TCPF_LISTEN,
  52. DCCPF_RESPOND = TCPF_SYN_RECV,
  53. DCCPF_ACTIVE_CLOSEREQ = TCPF_FIN_WAIT1,
  54. DCCPF_CLOSING = TCPF_CLOSING,
  55. DCCPF_TIME_WAIT = TCPF_TIME_WAIT,
  56. DCCPF_CLOSED = TCPF_CLOSE,
  57. DCCPF_NEW_SYN_RECV = TCPF_NEW_SYN_RECV,
  58. DCCPF_PARTOPEN = (1 << DCCP_PARTOPEN),
  59. };
  60. static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
  61. {
  62. return (struct dccp_hdr *)skb_transport_header(skb);
  63. }
  64. static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen)
  65. {
  66. skb_push(skb, headlen);
  67. skb_reset_transport_header(skb);
  68. return memset(skb_transport_header(skb), 0, headlen);
  69. }
  70. static inline struct dccp_hdr_ext *dccp_hdrx(const struct dccp_hdr *dh)
  71. {
  72. return (struct dccp_hdr_ext *)((unsigned char *)dh + sizeof(*dh));
  73. }
  74. static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
  75. {
  76. return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
  77. }
  78. static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
  79. {
  80. const struct dccp_hdr *dh = dccp_hdr(skb);
  81. return __dccp_basic_hdr_len(dh);
  82. }
  83. static inline __u64 dccp_hdr_seq(const struct dccp_hdr *dh)
  84. {
  85. __u64 seq_nr = ntohs(dh->dccph_seq);
  86. if (dh->dccph_x != 0)
  87. seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(dh)->dccph_seq_low);
  88. else
  89. seq_nr += (u32)dh->dccph_seq2 << 16;
  90. return seq_nr;
  91. }
  92. static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
  93. {
  94. return (struct dccp_hdr_request *)(skb_transport_header(skb) +
  95. dccp_basic_hdr_len(skb));
  96. }
  97. static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
  98. {
  99. return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) +
  100. dccp_basic_hdr_len(skb));
  101. }
  102. static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
  103. {
  104. const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
  105. return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
  106. }
  107. static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
  108. {
  109. return (struct dccp_hdr_response *)(skb_transport_header(skb) +
  110. dccp_basic_hdr_len(skb));
  111. }
  112. static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
  113. {
  114. return (struct dccp_hdr_reset *)(skb_transport_header(skb) +
  115. dccp_basic_hdr_len(skb));
  116. }
  117. static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
  118. {
  119. return __dccp_basic_hdr_len(dh) +
  120. dccp_packet_hdr_len(dh->dccph_type);
  121. }
  122. static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
  123. {
  124. return __dccp_hdr_len(dccp_hdr(skb));
  125. }
  126. /**
  127. * struct dccp_request_sock - represent DCCP-specific connection request
  128. * @dreq_inet_rsk: structure inherited from
  129. * @dreq_iss: initial sequence number, sent on the first Response (RFC 4340, 7.1)
  130. * @dreq_gss: greatest sequence number sent (for retransmitted Responses)
  131. * @dreq_isr: initial sequence number received in the first Request
  132. * @dreq_gsr: greatest sequence number received (for retransmitted Request(s))
  133. * @dreq_service: service code present on the Request (there is just one)
  134. * @dreq_featneg: feature negotiation options for this connection
  135. * The following two fields are analogous to the ones in dccp_sock:
  136. * @dreq_timestamp_echo: last received timestamp to echo (13.1)
  137. * @dreq_timestamp_echo: the time of receiving the last @dreq_timestamp_echo
  138. */
  139. struct dccp_request_sock {
  140. struct inet_request_sock dreq_inet_rsk;
  141. __u64 dreq_iss;
  142. __u64 dreq_gss;
  143. __u64 dreq_isr;
  144. __u64 dreq_gsr;
  145. __be32 dreq_service;
  146. spinlock_t dreq_lock;
  147. struct list_head dreq_featneg;
  148. __u32 dreq_timestamp_echo;
  149. __u32 dreq_timestamp_time;
  150. };
  151. static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
  152. {
  153. return (struct dccp_request_sock *)req;
  154. }
  155. extern struct inet_timewait_death_row dccp_death_row;
  156. extern int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
  157. struct sk_buff *skb);
  158. struct dccp_options_received {
  159. u64 dccpor_ndp:48;
  160. u32 dccpor_timestamp;
  161. u32 dccpor_timestamp_echo;
  162. u32 dccpor_elapsed_time;
  163. };
  164. struct ccid;
  165. enum dccp_role {
  166. DCCP_ROLE_UNDEFINED,
  167. DCCP_ROLE_LISTEN,
  168. DCCP_ROLE_CLIENT,
  169. DCCP_ROLE_SERVER,
  170. };
  171. struct dccp_service_list {
  172. __u32 dccpsl_nr;
  173. __be32 dccpsl_list[];
  174. };
  175. #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
  176. #define DCCP_SERVICE_CODE_IS_ABSENT 0
  177. static inline bool dccp_list_has_service(const struct dccp_service_list *sl,
  178. const __be32 service)
  179. {
  180. if (likely(sl != NULL)) {
  181. u32 i = sl->dccpsl_nr;
  182. while (i--)
  183. if (sl->dccpsl_list[i] == service)
  184. return true;
  185. }
  186. return false;
  187. }
  188. struct dccp_ackvec;
  189. /**
  190. * struct dccp_sock - DCCP socket state
  191. *
  192. * @dccps_swl - sequence number window low
  193. * @dccps_swh - sequence number window high
  194. * @dccps_awl - acknowledgement number window low
  195. * @dccps_awh - acknowledgement number window high
  196. * @dccps_iss - initial sequence number sent
  197. * @dccps_isr - initial sequence number received
  198. * @dccps_osr - first OPEN sequence number received
  199. * @dccps_gss - greatest sequence number sent
  200. * @dccps_gsr - greatest valid sequence number received
  201. * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
  202. * @dccps_service - first (passive sock) or unique (active sock) service code
  203. * @dccps_service_list - second .. last service code on passive socket
  204. * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
  205. * @dccps_timestamp_time - time of receiving latest @dccps_timestamp_echo
  206. * @dccps_l_ack_ratio - feature-local Ack Ratio
  207. * @dccps_r_ack_ratio - feature-remote Ack Ratio
  208. * @dccps_l_seq_win - local Sequence Window (influences ack number validity)
  209. * @dccps_r_seq_win - remote Sequence Window (influences seq number validity)
  210. * @dccps_pcslen - sender partial checksum coverage (via sockopt)
  211. * @dccps_pcrlen - receiver partial checksum coverage (via sockopt)
  212. * @dccps_send_ndp_count - local Send NDP Count feature (7.7.2)
  213. * @dccps_ndp_count - number of Non Data Packets since last data packet
  214. * @dccps_mss_cache - current value of MSS (path MTU minus header sizes)
  215. * @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4)
  216. * @dccps_featneg - tracks feature-negotiation state (mostly during handshake)
  217. * @dccps_hc_rx_ackvec - rx half connection ack vector
  218. * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection)
  219. * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection)
  220. * @dccps_options_received - parsed set of retrieved options
  221. * @dccps_qpolicy - TX dequeueing policy, one of %dccp_packet_dequeueing_policy
  222. * @dccps_tx_qlen - maximum length of the TX queue
  223. * @dccps_role - role of this sock, one of %dccp_role
  224. * @dccps_hc_rx_insert_options - receiver wants to add options when acking
  225. * @dccps_hc_tx_insert_options - sender wants to add options when sending
  226. * @dccps_server_timewait - server holds timewait state on close (RFC 4340, 8.3)
  227. * @dccps_sync_scheduled - flag which signals "send out-of-band message soon"
  228. * @dccps_xmitlet - tasklet scheduled by the TX CCID to dequeue data packets
  229. * @dccps_xmit_timer - used by the TX CCID to delay sending (rate-based pacing)
  230. * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs)
  231. */
  232. struct dccp_sock {
  233. /* inet_connection_sock has to be the first member of dccp_sock */
  234. struct inet_connection_sock dccps_inet_connection;
  235. #define dccps_syn_rtt dccps_inet_connection.icsk_ack.lrcvtime
  236. __u64 dccps_swl;
  237. __u64 dccps_swh;
  238. __u64 dccps_awl;
  239. __u64 dccps_awh;
  240. __u64 dccps_iss;
  241. __u64 dccps_isr;
  242. __u64 dccps_osr;
  243. __u64 dccps_gss;
  244. __u64 dccps_gsr;
  245. __u64 dccps_gar;
  246. __be32 dccps_service;
  247. __u32 dccps_mss_cache;
  248. struct dccp_service_list *dccps_service_list;
  249. __u32 dccps_timestamp_echo;
  250. __u32 dccps_timestamp_time;
  251. __u16 dccps_l_ack_ratio;
  252. __u16 dccps_r_ack_ratio;
  253. __u64 dccps_l_seq_win:48;
  254. __u64 dccps_r_seq_win:48;
  255. __u8 dccps_pcslen:4;
  256. __u8 dccps_pcrlen:4;
  257. __u8 dccps_send_ndp_count:1;
  258. __u64 dccps_ndp_count:48;
  259. unsigned long dccps_rate_last;
  260. struct list_head dccps_featneg;
  261. struct dccp_ackvec *dccps_hc_rx_ackvec;
  262. struct ccid *dccps_hc_rx_ccid;
  263. struct ccid *dccps_hc_tx_ccid;
  264. struct dccp_options_received dccps_options_received;
  265. __u8 dccps_qpolicy;
  266. __u32 dccps_tx_qlen;
  267. enum dccp_role dccps_role:2;
  268. __u8 dccps_hc_rx_insert_options:1;
  269. __u8 dccps_hc_tx_insert_options:1;
  270. __u8 dccps_server_timewait:1;
  271. __u8 dccps_sync_scheduled:1;
  272. struct tasklet_struct dccps_xmitlet;
  273. struct timer_list dccps_xmit_timer;
  274. };
  275. static inline struct dccp_sock *dccp_sk(const struct sock *sk)
  276. {
  277. return (struct dccp_sock *)sk;
  278. }
  279. static inline const char *dccp_role(const struct sock *sk)
  280. {
  281. switch (dccp_sk(sk)->dccps_role) {
  282. case DCCP_ROLE_UNDEFINED: return "undefined";
  283. case DCCP_ROLE_LISTEN: return "listen";
  284. case DCCP_ROLE_SERVER: return "server";
  285. case DCCP_ROLE_CLIENT: return "client";
  286. }
  287. return NULL;
  288. }
  289. extern void dccp_syn_ack_timeout(const struct request_sock *req);
  290. #endif /* _LINUX_DCCP_H */