dccp.h 15 KB

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  1. #ifndef _LINUX_DCCP_H
  2. #define _LINUX_DCCP_H
  3. #include <linux/types.h>
  4. #include <asm/byteorder.h>
  5. /**
  6. * struct dccp_hdr - generic part of DCCP packet header
  7. *
  8. * @dccph_sport - Relevant port on the endpoint that sent this packet
  9. * @dccph_dport - Relevant port on the other endpoint
  10. * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
  11. * @dccph_ccval - Used by the HC-Sender CCID
  12. * @dccph_cscov - Parts of the packet that are covered by the Checksum field
  13. * @dccph_checksum - Internet checksum, depends on dccph_cscov
  14. * @dccph_x - 0 = 24 bit sequence number, 1 = 48
  15. * @dccph_type - packet type, see DCCP_PKT_ prefixed macros
  16. * @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x
  17. */
  18. struct dccp_hdr {
  19. __be16 dccph_sport,
  20. dccph_dport;
  21. __u8 dccph_doff;
  22. #if defined(__LITTLE_ENDIAN_BITFIELD)
  23. __u8 dccph_cscov:4,
  24. dccph_ccval:4;
  25. #elif defined(__BIG_ENDIAN_BITFIELD)
  26. __u8 dccph_ccval:4,
  27. dccph_cscov:4;
  28. #else
  29. #error "Adjust your <asm/byteorder.h> defines"
  30. #endif
  31. __sum16 dccph_checksum;
  32. #if defined(__LITTLE_ENDIAN_BITFIELD)
  33. __u8 dccph_x:1,
  34. dccph_type:4,
  35. dccph_reserved:3;
  36. #elif defined(__BIG_ENDIAN_BITFIELD)
  37. __u8 dccph_reserved:3,
  38. dccph_type:4,
  39. dccph_x:1;
  40. #else
  41. #error "Adjust your <asm/byteorder.h> defines"
  42. #endif
  43. __u8 dccph_seq2;
  44. __be16 dccph_seq;
  45. };
  46. /**
  47. * struct dccp_hdr_ext - the low bits of a 48 bit seq packet
  48. *
  49. * @dccph_seq_low - low 24 bits of a 48 bit seq packet
  50. */
  51. struct dccp_hdr_ext {
  52. __be32 dccph_seq_low;
  53. };
  54. /**
  55. * struct dccp_hdr_request - Connection initiation request header
  56. *
  57. * @dccph_req_service - Service to which the client app wants to connect
  58. */
  59. struct dccp_hdr_request {
  60. __be32 dccph_req_service;
  61. };
  62. /**
  63. * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
  64. *
  65. * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
  66. * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
  67. */
  68. struct dccp_hdr_ack_bits {
  69. __be16 dccph_reserved1;
  70. __be16 dccph_ack_nr_high;
  71. __be32 dccph_ack_nr_low;
  72. };
  73. /**
  74. * struct dccp_hdr_response - Connection initiation response header
  75. *
  76. * @dccph_resp_ack - 48 bit Acknowledgment Number Subheader (5.3)
  77. * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
  78. */
  79. struct dccp_hdr_response {
  80. struct dccp_hdr_ack_bits dccph_resp_ack;
  81. __be32 dccph_resp_service;
  82. };
  83. /**
  84. * struct dccp_hdr_reset - Unconditionally shut down a connection
  85. *
  86. * @dccph_reset_ack - 48 bit Acknowledgment Number Subheader (5.6)
  87. * @dccph_reset_code - one of %dccp_reset_codes
  88. * @dccph_reset_data - the Data 1 ... Data 3 fields from 5.6
  89. */
  90. struct dccp_hdr_reset {
  91. struct dccp_hdr_ack_bits dccph_reset_ack;
  92. __u8 dccph_reset_code,
  93. dccph_reset_data[3];
  94. };
  95. enum dccp_pkt_type {
  96. DCCP_PKT_REQUEST = 0,
  97. DCCP_PKT_RESPONSE,
  98. DCCP_PKT_DATA,
  99. DCCP_PKT_ACK,
  100. DCCP_PKT_DATAACK,
  101. DCCP_PKT_CLOSEREQ,
  102. DCCP_PKT_CLOSE,
  103. DCCP_PKT_RESET,
  104. DCCP_PKT_SYNC,
  105. DCCP_PKT_SYNCACK,
  106. DCCP_PKT_INVALID,
  107. };
  108. #define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
  109. static inline unsigned int dccp_packet_hdr_len(const __u8 type)
  110. {
  111. if (type == DCCP_PKT_DATA)
  112. return 0;
  113. if (type == DCCP_PKT_DATAACK ||
  114. type == DCCP_PKT_ACK ||
  115. type == DCCP_PKT_SYNC ||
  116. type == DCCP_PKT_SYNCACK ||
  117. type == DCCP_PKT_CLOSE ||
  118. type == DCCP_PKT_CLOSEREQ)
  119. return sizeof(struct dccp_hdr_ack_bits);
  120. if (type == DCCP_PKT_REQUEST)
  121. return sizeof(struct dccp_hdr_request);
  122. if (type == DCCP_PKT_RESPONSE)
  123. return sizeof(struct dccp_hdr_response);
  124. return sizeof(struct dccp_hdr_reset);
  125. }
  126. enum dccp_reset_codes {
  127. DCCP_RESET_CODE_UNSPECIFIED = 0,
  128. DCCP_RESET_CODE_CLOSED,
  129. DCCP_RESET_CODE_ABORTED,
  130. DCCP_RESET_CODE_NO_CONNECTION,
  131. DCCP_RESET_CODE_PACKET_ERROR,
  132. DCCP_RESET_CODE_OPTION_ERROR,
  133. DCCP_RESET_CODE_MANDATORY_ERROR,
  134. DCCP_RESET_CODE_CONNECTION_REFUSED,
  135. DCCP_RESET_CODE_BAD_SERVICE_CODE,
  136. DCCP_RESET_CODE_TOO_BUSY,
  137. DCCP_RESET_CODE_BAD_INIT_COOKIE,
  138. DCCP_RESET_CODE_AGGRESSION_PENALTY,
  139. };
  140. /* DCCP options */
  141. enum {
  142. DCCPO_PADDING = 0,
  143. DCCPO_MANDATORY = 1,
  144. DCCPO_MIN_RESERVED = 3,
  145. DCCPO_MAX_RESERVED = 31,
  146. DCCPO_CHANGE_L = 32,
  147. DCCPO_CONFIRM_L = 33,
  148. DCCPO_CHANGE_R = 34,
  149. DCCPO_CONFIRM_R = 35,
  150. DCCPO_NDP_COUNT = 37,
  151. DCCPO_ACK_VECTOR_0 = 38,
  152. DCCPO_ACK_VECTOR_1 = 39,
  153. DCCPO_TIMESTAMP = 41,
  154. DCCPO_TIMESTAMP_ECHO = 42,
  155. DCCPO_ELAPSED_TIME = 43,
  156. DCCPO_MAX = 45,
  157. DCCPO_MIN_CCID_SPECIFIC = 128,
  158. DCCPO_MAX_CCID_SPECIFIC = 255,
  159. };
  160. /* DCCP CCIDS */
  161. enum {
  162. DCCPC_CCID2 = 2,
  163. DCCPC_CCID3 = 3,
  164. };
  165. /* DCCP features (RFC 4340 section 6.4) */
  166. enum {
  167. DCCPF_RESERVED = 0,
  168. DCCPF_CCID = 1,
  169. DCCPF_SHORT_SEQNOS = 2, /* XXX: not yet implemented */
  170. DCCPF_SEQUENCE_WINDOW = 3,
  171. DCCPF_ECN_INCAPABLE = 4, /* XXX: not yet implemented */
  172. DCCPF_ACK_RATIO = 5,
  173. DCCPF_SEND_ACK_VECTOR = 6,
  174. DCCPF_SEND_NDP_COUNT = 7,
  175. DCCPF_MIN_CSUM_COVER = 8,
  176. DCCPF_DATA_CHECKSUM = 9, /* XXX: not yet implemented */
  177. /* 10-127 reserved */
  178. DCCPF_MIN_CCID_SPECIFIC = 128,
  179. DCCPF_MAX_CCID_SPECIFIC = 255,
  180. };
  181. /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
  182. struct dccp_so_feat {
  183. __u8 dccpsf_feat;
  184. __u8 __user *dccpsf_val;
  185. __u8 dccpsf_len;
  186. };
  187. /* DCCP socket options */
  188. #define DCCP_SOCKOPT_PACKET_SIZE 1 /* XXX deprecated, without effect */
  189. #define DCCP_SOCKOPT_SERVICE 2
  190. #define DCCP_SOCKOPT_CHANGE_L 3
  191. #define DCCP_SOCKOPT_CHANGE_R 4
  192. #define DCCP_SOCKOPT_GET_CUR_MPS 5
  193. #define DCCP_SOCKOPT_SEND_CSCOV 10
  194. #define DCCP_SOCKOPT_RECV_CSCOV 11
  195. #define DCCP_SOCKOPT_CCID_RX_INFO 128
  196. #define DCCP_SOCKOPT_CCID_TX_INFO 192
  197. /* maximum number of services provided on the same listening port */
  198. #define DCCP_SERVICE_LIST_MAX_LEN 32
  199. #ifdef __KERNEL__
  200. #include <linux/in.h>
  201. #include <linux/ktime.h>
  202. #include <linux/list.h>
  203. #include <linux/uio.h>
  204. #include <linux/workqueue.h>
  205. #include <net/inet_connection_sock.h>
  206. #include <net/inet_sock.h>
  207. #include <net/inet_timewait_sock.h>
  208. #include <net/tcp_states.h>
  209. enum dccp_state {
  210. DCCP_OPEN = TCP_ESTABLISHED,
  211. DCCP_REQUESTING = TCP_SYN_SENT,
  212. DCCP_PARTOPEN = TCP_FIN_WAIT1, /* FIXME:
  213. This mapping is horrible, but TCP has
  214. no matching state for DCCP_PARTOPEN,
  215. as TCP_SYN_RECV is already used by
  216. DCCP_RESPOND, why don't stop using TCP
  217. mapping of states? OK, now we don't use
  218. sk_stream_sendmsg anymore, so doesn't
  219. seem to exist any reason for us to
  220. do the TCP mapping here */
  221. DCCP_LISTEN = TCP_LISTEN,
  222. DCCP_RESPOND = TCP_SYN_RECV,
  223. DCCP_CLOSING = TCP_CLOSING,
  224. DCCP_TIME_WAIT = TCP_TIME_WAIT,
  225. DCCP_CLOSED = TCP_CLOSE,
  226. DCCP_MAX_STATES = TCP_MAX_STATES,
  227. };
  228. #define DCCP_STATE_MASK 0xf
  229. #define DCCP_ACTION_FIN (1<<7)
  230. enum {
  231. DCCPF_OPEN = TCPF_ESTABLISHED,
  232. DCCPF_REQUESTING = TCPF_SYN_SENT,
  233. DCCPF_PARTOPEN = TCPF_FIN_WAIT1,
  234. DCCPF_LISTEN = TCPF_LISTEN,
  235. DCCPF_RESPOND = TCPF_SYN_RECV,
  236. DCCPF_CLOSING = TCPF_CLOSING,
  237. DCCPF_TIME_WAIT = TCPF_TIME_WAIT,
  238. DCCPF_CLOSED = TCPF_CLOSE,
  239. };
  240. static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
  241. {
  242. return (struct dccp_hdr *)skb_transport_header(skb);
  243. }
  244. static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen)
  245. {
  246. skb_push(skb, headlen);
  247. skb_reset_transport_header(skb);
  248. return memset(skb_transport_header(skb), 0, headlen);
  249. }
  250. static inline struct dccp_hdr_ext *dccp_hdrx(const struct dccp_hdr *dh)
  251. {
  252. return (struct dccp_hdr_ext *)((unsigned char *)dh + sizeof(*dh));
  253. }
  254. static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
  255. {
  256. return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
  257. }
  258. static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
  259. {
  260. const struct dccp_hdr *dh = dccp_hdr(skb);
  261. return __dccp_basic_hdr_len(dh);
  262. }
  263. static inline __u64 dccp_hdr_seq(const struct dccp_hdr *dh)
  264. {
  265. __u64 seq_nr = ntohs(dh->dccph_seq);
  266. if (dh->dccph_x != 0)
  267. seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(dh)->dccph_seq_low);
  268. else
  269. seq_nr += (u32)dh->dccph_seq2 << 16;
  270. return seq_nr;
  271. }
  272. static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
  273. {
  274. return (struct dccp_hdr_request *)(skb_transport_header(skb) +
  275. dccp_basic_hdr_len(skb));
  276. }
  277. static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
  278. {
  279. return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) +
  280. dccp_basic_hdr_len(skb));
  281. }
  282. static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
  283. {
  284. const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
  285. return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
  286. }
  287. static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
  288. {
  289. return (struct dccp_hdr_response *)(skb_transport_header(skb) +
  290. dccp_basic_hdr_len(skb));
  291. }
  292. static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
  293. {
  294. return (struct dccp_hdr_reset *)(skb_transport_header(skb) +
  295. dccp_basic_hdr_len(skb));
  296. }
  297. static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
  298. {
  299. return __dccp_basic_hdr_len(dh) +
  300. dccp_packet_hdr_len(dh->dccph_type);
  301. }
  302. static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
  303. {
  304. return __dccp_hdr_len(dccp_hdr(skb));
  305. }
  306. /* initial values for each feature */
  307. #define DCCPF_INITIAL_SEQUENCE_WINDOW 100
  308. #define DCCPF_INITIAL_ACK_RATIO 2
  309. #define DCCPF_INITIAL_CCID DCCPC_CCID2
  310. #define DCCPF_INITIAL_SEND_ACK_VECTOR 1
  311. /* FIXME: for now we're default to 1 but it should really be 0 */
  312. #define DCCPF_INITIAL_SEND_NDP_COUNT 1
  313. #define DCCP_NDP_LIMIT 0xFFFFFF
  314. /**
  315. * struct dccp_minisock - Minimal DCCP connection representation
  316. *
  317. * Will be used to pass the state from dccp_request_sock to dccp_sock.
  318. *
  319. * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
  320. * @dccpms_ccid - Congestion Control Id (CCID) (section 10)
  321. * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)
  322. * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)
  323. * @dccpms_ack_ratio - Ack Ratio Feature (section 11.3)
  324. * @dccpms_pending - List of features being negotiated
  325. * @dccpms_conf -
  326. */
  327. struct dccp_minisock {
  328. __u64 dccpms_sequence_window;
  329. __u8 dccpms_rx_ccid;
  330. __u8 dccpms_tx_ccid;
  331. __u8 dccpms_send_ack_vector;
  332. __u8 dccpms_send_ndp_count;
  333. __u8 dccpms_ack_ratio;
  334. struct list_head dccpms_pending;
  335. struct list_head dccpms_conf;
  336. };
  337. struct dccp_opt_conf {
  338. __u8 *dccpoc_val;
  339. __u8 dccpoc_len;
  340. };
  341. struct dccp_opt_pend {
  342. struct list_head dccpop_node;
  343. __u8 dccpop_type;
  344. __u8 dccpop_feat;
  345. __u8 *dccpop_val;
  346. __u8 dccpop_len;
  347. int dccpop_conf;
  348. struct dccp_opt_conf *dccpop_sc;
  349. };
  350. extern void dccp_minisock_init(struct dccp_minisock *dmsk);
  351. extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
  352. struct dccp_request_sock {
  353. struct inet_request_sock dreq_inet_rsk;
  354. __u64 dreq_iss;
  355. __u64 dreq_isr;
  356. __be32 dreq_service;
  357. };
  358. static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
  359. {
  360. return (struct dccp_request_sock *)req;
  361. }
  362. extern struct inet_timewait_death_row dccp_death_row;
  363. struct dccp_options_received {
  364. u32 dccpor_ndp; /* only 24 bits */
  365. u32 dccpor_timestamp;
  366. u32 dccpor_timestamp_echo;
  367. u32 dccpor_elapsed_time;
  368. };
  369. struct ccid;
  370. enum dccp_role {
  371. DCCP_ROLE_UNDEFINED,
  372. DCCP_ROLE_LISTEN,
  373. DCCP_ROLE_CLIENT,
  374. DCCP_ROLE_SERVER,
  375. };
  376. struct dccp_service_list {
  377. __u32 dccpsl_nr;
  378. __be32 dccpsl_list[0];
  379. };
  380. #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
  381. #define DCCP_SERVICE_CODE_IS_ABSENT 0
  382. static inline int dccp_list_has_service(const struct dccp_service_list *sl,
  383. const __be32 service)
  384. {
  385. if (likely(sl != NULL)) {
  386. u32 i = sl->dccpsl_nr;
  387. while (i--)
  388. if (sl->dccpsl_list[i] == service)
  389. return 1;
  390. }
  391. return 0;
  392. }
  393. struct dccp_ackvec;
  394. /**
  395. * struct dccp_sock - DCCP socket state
  396. *
  397. * @dccps_swl - sequence number window low
  398. * @dccps_swh - sequence number window high
  399. * @dccps_awl - acknowledgement number window low
  400. * @dccps_awh - acknowledgement number window high
  401. * @dccps_iss - initial sequence number sent
  402. * @dccps_isr - initial sequence number received
  403. * @dccps_osr - first OPEN sequence number received
  404. * @dccps_gss - greatest sequence number sent
  405. * @dccps_gsr - greatest valid sequence number received
  406. * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
  407. * @dccps_service - first (passive sock) or unique (active sock) service code
  408. * @dccps_service_list - second .. last service code on passive socket
  409. * @dccps_timestamp_time - time of latest TIMESTAMP option
  410. * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
  411. * @dccps_l_ack_ratio - feature-local Ack Ratio
  412. * @dccps_r_ack_ratio - feature-remote Ack Ratio
  413. * @dccps_pcslen - sender partial checksum coverage (via sockopt)
  414. * @dccps_pcrlen - receiver partial checksum coverage (via sockopt)
  415. * @dccps_ndp_count - number of Non Data Packets since last data packet
  416. * @dccps_mss_cache - current value of MSS (path MTU minus header sizes)
  417. * @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4)
  418. * @dccps_minisock - associated minisock (accessed via dccp_msk)
  419. * @dccps_hc_rx_ackvec - rx half connection ack vector
  420. * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection)
  421. * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection)
  422. * @dccps_options_received - parsed set of retrieved options
  423. * @dccps_role - role of this sock, one of %dccp_role
  424. * @dccps_hc_rx_insert_options - receiver wants to add options when acking
  425. * @dccps_hc_tx_insert_options - sender wants to add options when sending
  426. * @dccps_xmit_timer - timer for when CCID is not ready to send
  427. * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs)
  428. */
  429. struct dccp_sock {
  430. /* inet_connection_sock has to be the first member of dccp_sock */
  431. struct inet_connection_sock dccps_inet_connection;
  432. #define dccps_syn_rtt dccps_inet_connection.icsk_ack.lrcvtime
  433. __u64 dccps_swl;
  434. __u64 dccps_swh;
  435. __u64 dccps_awl;
  436. __u64 dccps_awh;
  437. __u64 dccps_iss;
  438. __u64 dccps_isr;
  439. __u64 dccps_osr;
  440. __u64 dccps_gss;
  441. __u64 dccps_gsr;
  442. __u64 dccps_gar;
  443. __be32 dccps_service;
  444. struct dccp_service_list *dccps_service_list;
  445. ktime_t dccps_timestamp_time;
  446. __u32 dccps_timestamp_echo;
  447. __u16 dccps_l_ack_ratio;
  448. __u16 dccps_r_ack_ratio;
  449. __u16 dccps_pcslen;
  450. __u16 dccps_pcrlen;
  451. unsigned long dccps_ndp_count;
  452. __u32 dccps_mss_cache;
  453. unsigned long dccps_rate_last;
  454. struct dccp_minisock dccps_minisock;
  455. struct dccp_ackvec *dccps_hc_rx_ackvec;
  456. struct ccid *dccps_hc_rx_ccid;
  457. struct ccid *dccps_hc_tx_ccid;
  458. struct dccp_options_received dccps_options_received;
  459. enum dccp_role dccps_role:2;
  460. __u8 dccps_hc_rx_insert_options:1;
  461. __u8 dccps_hc_tx_insert_options:1;
  462. struct timer_list dccps_xmit_timer;
  463. };
  464. static inline struct dccp_sock *dccp_sk(const struct sock *sk)
  465. {
  466. return (struct dccp_sock *)sk;
  467. }
  468. static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
  469. {
  470. return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
  471. }
  472. static inline const char *dccp_role(const struct sock *sk)
  473. {
  474. switch (dccp_sk(sk)->dccps_role) {
  475. case DCCP_ROLE_UNDEFINED: return "undefined";
  476. case DCCP_ROLE_LISTEN: return "listen";
  477. case DCCP_ROLE_SERVER: return "server";
  478. case DCCP_ROLE_CLIENT: return "client";
  479. }
  480. return NULL;
  481. }
  482. #endif /* __KERNEL__ */
  483. #endif /* _LINUX_DCCP_H */