1/* 2 * ip.h 3 * 4 * Internet Protocol (RFC 791). 5 * 6 * Copyright (c) 2000 Dug Song <dugsong@monkey.org> 7 * 8 * $Id: ip.h,v 1.23 2003/03/16 17:39:17 dugsong Exp $ 9 */ 10 11#ifndef DNET_IP_H 12#define DNET_IP_H 13 14#define IP_ADDR_LEN 4 /* IP address length */ 15#define IP_ADDR_BITS 32 /* IP address bits */ 16 17#define IP_HDR_LEN 20 /* base IP header length */ 18#define IP_OPT_LEN 2 /* base IP option length */ 19#define IP_OPT_LEN_MAX 40 20#define IP_HDR_LEN_MAX (IP_HDR_LEN + IP_OPT_LEN_MAX) 21 22#define IP_LEN_MAX 65535 23#define IP_LEN_MIN IP_HDR_LEN 24 25typedef uint32_t ip_addr_t; 26 27#ifndef __GNUC__ 28# define __attribute__(x) 29# pragma pack(1) 30#endif 31 32/* 33 * IP header, without options 34 */ 35struct ip_hdr { 36#if DNET_BYTESEX == DNET_BIG_ENDIAN 37 uint8_t ip_v:4, /* version */ 38 ip_hl:4; /* header length (incl any options) */ 39#elif DNET_BYTESEX == DNET_LIL_ENDIAN 40 uint8_t ip_hl:4, 41 ip_v:4; 42#else 43# error "need to include <dnet.h>" 44#endif 45 uint8_t ip_tos; /* type of service */ 46 uint16_t ip_len; /* total length (incl header) */ 47 uint16_t ip_id; /* identification */ 48 uint16_t ip_off; /* fragment offset and flags */ 49 uint8_t ip_ttl; /* time to live */ 50 uint8_t ip_p; /* protocol */ 51 uint16_t ip_sum; /* checksum */ 52 ip_addr_t ip_src; /* source address */ 53 ip_addr_t ip_dst; /* destination address */ 54}; 55 56/* 57 * Type of service (ip_tos), RFC 1349 ("obsoleted by RFC 2474") 58 */ 59#define IP_TOS_DEFAULT 0x00 /* default */ 60#define IP_TOS_LOWDELAY 0x10 /* low delay */ 61#define IP_TOS_THROUGHPUT 0x08 /* high throughput */ 62#define IP_TOS_RELIABILITY 0x04 /* high reliability */ 63#define IP_TOS_LOWCOST 0x02 /* low monetary cost - XXX */ 64#define IP_TOS_ECT 0x02 /* ECN-capable transport */ 65#define IP_TOS_CE 0x01 /* congestion experienced */ 66 67/* 68 * IP precedence (high 3 bits of ip_tos), hopefully unused 69 */ 70#define IP_TOS_PREC_ROUTINE 0x00 71#define IP_TOS_PREC_PRIORITY 0x20 72#define IP_TOS_PREC_IMMEDIATE 0x40 73#define IP_TOS_PREC_FLASH 0x60 74#define IP_TOS_PREC_FLASHOVERRIDE 0x80 75#define IP_TOS_PREC_CRITIC_ECP 0xa0 76#define IP_TOS_PREC_INTERNETCONTROL 0xc0 77#define IP_TOS_PREC_NETCONTROL 0xe0 78 79/* 80 * Fragmentation flags (ip_off) 81 */ 82#define IP_RF 0x8000 /* reserved */ 83#define IP_DF 0x4000 /* don't fragment */ 84#define IP_MF 0x2000 /* more fragments (not last frag) */ 85#define IP_OFFMASK 0x1fff /* mask for fragment offset */ 86 87/* 88 * Time-to-live (ip_ttl), seconds 89 */ 90#define IP_TTL_DEFAULT 64 /* default ttl, RFC 1122, RFC 1340 */ 91#define IP_TTL_MAX 255 /* maximum ttl */ 92 93/* 94 * Protocol (ip_p) - http://www.iana.org/assignments/protocol-numbers 95 */ 96#define IP_PROTO_IP 0 /* dummy for IP */ 97#define IP_PROTO_HOPOPTS IP_PROTO_IP /* IPv6 hop-by-hop options */ 98#define IP_PROTO_ICMP 1 /* ICMP */ 99#define IP_PROTO_IGMP 2 /* IGMP */ 100#define IP_PROTO_GGP 3 /* gateway-gateway protocol */ 101#define IP_PROTO_IPIP 4 /* IP in IP */ 102#define IP_PROTO_ST 5 /* ST datagram mode */ 103#define IP_PROTO_TCP 6 /* TCP */ 104#define IP_PROTO_CBT 7 /* CBT */ 105#define IP_PROTO_EGP 8 /* exterior gateway protocol */ 106#define IP_PROTO_IGP 9 /* interior gateway protocol */ 107#define IP_PROTO_BBNRCC 10 /* BBN RCC monitoring */ 108#define IP_PROTO_NVP 11 /* Network Voice Protocol */ 109#define IP_PROTO_PUP 12 /* PARC universal packet */ 110#define IP_PROTO_ARGUS 13 /* ARGUS */ 111#define IP_PROTO_EMCON 14 /* EMCON */ 112#define IP_PROTO_XNET 15 /* Cross Net Debugger */ 113#define IP_PROTO_CHAOS 16 /* Chaos */ 114#define IP_PROTO_UDP 17 /* UDP */ 115#define IP_PROTO_MUX 18 /* multiplexing */ 116#define IP_PROTO_DCNMEAS 19 /* DCN measurement */ 117#define IP_PROTO_HMP 20 /* Host Monitoring Protocol */ 118#define IP_PROTO_PRM 21 /* Packet Radio Measurement */ 119#define IP_PROTO_IDP 22 /* Xerox NS IDP */ 120#define IP_PROTO_TRUNK1 23 /* Trunk-1 */ 121#define IP_PROTO_TRUNK2 24 /* Trunk-2 */ 122#define IP_PROTO_LEAF1 25 /* Leaf-1 */ 123#define IP_PROTO_LEAF2 26 /* Leaf-2 */ 124#define IP_PROTO_RDP 27 /* "Reliable Datagram" proto */ 125#define IP_PROTO_IRTP 28 /* Inet Reliable Transaction */ 126#define IP_PROTO_TP 29 /* ISO TP class 4 */ 127#define IP_PROTO_NETBLT 30 /* Bulk Data Transfer */ 128#define IP_PROTO_MFPNSP 31 /* MFE Network Services */ 129#define IP_PROTO_MERITINP 32 /* Merit Internodal Protocol */ 130#define IP_PROTO_SEP 33 /* Sequential Exchange proto */ 131#define IP_PROTO_3PC 34 /* Third Party Connect proto */ 132#define IP_PROTO_IDPR 35 /* Interdomain Policy Route */ 133#define IP_PROTO_XTP 36 /* Xpress Transfer Protocol */ 134#define IP_PROTO_DDP 37 /* Datagram Delivery Proto */ 135#define IP_PROTO_CMTP 38 /* IDPR Ctrl Message Trans */ 136#define IP_PROTO_TPPP 39 /* TP++ Transport Protocol */ 137#define IP_PROTO_IL 40 /* IL Transport Protocol */ 138#define IP_PROTO_IPV6 41 /* IPv6 */ 139#define IP_PROTO_SDRP 42 /* Source Demand Routing */ 140#define IP_PROTO_ROUTING 43 /* IPv6 routing header */ 141#define IP_PROTO_FRAGMENT 44 /* IPv6 fragmentation header */ 142#define IP_PROTO_RSVP 46 /* Reservation protocol */ 143#define IP_PROTO_GRE 47 /* General Routing Encap */ 144#define IP_PROTO_MHRP 48 /* Mobile Host Routing */ 145#define IP_PROTO_ENA 49 /* ENA */ 146#define IP_PROTO_ESP 50 /* Encap Security Payload */ 147#define IP_PROTO_AH 51 /* Authentication Header */ 148#define IP_PROTO_INLSP 52 /* Integated Net Layer Sec */ 149#define IP_PROTO_SWIPE 53 /* SWIPE */ 150#define IP_PROTO_NARP 54 /* NBMA Address Resolution */ 151#define IP_PROTO_MOBILE 55 /* Mobile IP, RFC 2004 */ 152#define IP_PROTO_TLSP 56 /* Transport Layer Security */ 153#define IP_PROTO_SKIP 57 /* SKIP */ 154#define IP_PROTO_ICMPV6 58 /* ICMP for IPv6 */ 155#define IP_PROTO_NONE 59 /* IPv6 no next header */ 156#define IP_PROTO_DSTOPTS 60 /* IPv6 destination options */ 157#define IP_PROTO_ANYHOST 61 /* any host internal proto */ 158#define IP_PROTO_CFTP 62 /* CFTP */ 159#define IP_PROTO_ANYNET 63 /* any local network */ 160#define IP_PROTO_EXPAK 64 /* SATNET and Backroom EXPAK */ 161#define IP_PROTO_KRYPTOLAN 65 /* Kryptolan */ 162#define IP_PROTO_RVD 66 /* MIT Remote Virtual Disk */ 163#define IP_PROTO_IPPC 67 /* Inet Pluribus Packet Core */ 164#define IP_PROTO_DISTFS 68 /* any distributed fs */ 165#define IP_PROTO_SATMON 69 /* SATNET Monitoring */ 166#define IP_PROTO_VISA 70 /* VISA Protocol */ 167#define IP_PROTO_IPCV 71 /* Inet Packet Core Utility */ 168#define IP_PROTO_CPNX 72 /* Comp Proto Net Executive */ 169#define IP_PROTO_CPHB 73 /* Comp Protocol Heart Beat */ 170#define IP_PROTO_WSN 74 /* Wang Span Network */ 171#define IP_PROTO_PVP 75 /* Packet Video Protocol */ 172#define IP_PROTO_BRSATMON 76 /* Backroom SATNET Monitor */ 173#define IP_PROTO_SUNND 77 /* SUN ND Protocol */ 174#define IP_PROTO_WBMON 78 /* WIDEBAND Monitoring */ 175#define IP_PROTO_WBEXPAK 79 /* WIDEBAND EXPAK */ 176#define IP_PROTO_EON 80 /* ISO CNLP */ 177#define IP_PROTO_VMTP 81 /* Versatile Msg Transport*/ 178#define IP_PROTO_SVMTP 82 /* Secure VMTP */ 179#define IP_PROTO_VINES 83 /* VINES */ 180#define IP_PROTO_TTP 84 /* TTP */ 181#define IP_PROTO_NSFIGP 85 /* NSFNET-IGP */ 182#define IP_PROTO_DGP 86 /* Dissimilar Gateway Proto */ 183#define IP_PROTO_TCF 87 /* TCF */ 184#define IP_PROTO_EIGRP 88 /* EIGRP */ 185#define IP_PROTO_OSPF 89 /* Open Shortest Path First */ 186#define IP_PROTO_SPRITERPC 90 /* Sprite RPC Protocol */ 187#define IP_PROTO_LARP 91 /* Locus Address Resolution */ 188#define IP_PROTO_MTP 92 /* Multicast Transport Proto */ 189#define IP_PROTO_AX25 93 /* AX.25 Frames */ 190#define IP_PROTO_IPIPENCAP 94 /* yet-another IP encap */ 191#define IP_PROTO_MICP 95 /* Mobile Internet Ctrl */ 192#define IP_PROTO_SCCSP 96 /* Semaphore Comm Sec Proto */ 193#define IP_PROTO_ETHERIP 97 /* Ethernet in IPv4 */ 194#define IP_PROTO_ENCAP 98 /* encapsulation header */ 195#define IP_PROTO_ANYENC 99 /* private encryption scheme */ 196#define IP_PROTO_GMTP 100 /* GMTP */ 197#define IP_PROTO_IFMP 101 /* Ipsilon Flow Mgmt Proto */ 198#define IP_PROTO_PNNI 102 /* PNNI over IP */ 199#define IP_PROTO_PIM 103 /* Protocol Indep Multicast */ 200#define IP_PROTO_ARIS 104 /* ARIS */ 201#define IP_PROTO_SCPS 105 /* SCPS */ 202#define IP_PROTO_QNX 106 /* QNX */ 203#define IP_PROTO_AN 107 /* Active Networks */ 204#define IP_PROTO_IPCOMP 108 /* IP Payload Compression */ 205#define IP_PROTO_SNP 109 /* Sitara Networks Protocol */ 206#define IP_PROTO_COMPAQPEER 110 /* Compaq Peer Protocol */ 207#define IP_PROTO_IPXIP 111 /* IPX in IP */ 208#define IP_PROTO_VRRP 112 /* Virtual Router Redundancy */ 209#define IP_PROTO_PGM 113 /* PGM Reliable Transport */ 210#define IP_PROTO_ANY0HOP 114 /* 0-hop protocol */ 211#define IP_PROTO_L2TP 115 /* Layer 2 Tunneling Proto */ 212#define IP_PROTO_DDX 116 /* D-II Data Exchange (DDX) */ 213#define IP_PROTO_IATP 117 /* Interactive Agent Xfer */ 214#define IP_PROTO_STP 118 /* Schedule Transfer Proto */ 215#define IP_PROTO_SRP 119 /* SpectraLink Radio Proto */ 216#define IP_PROTO_UTI 120 /* UTI */ 217#define IP_PROTO_SMP 121 /* Simple Message Protocol */ 218#define IP_PROTO_SM 122 /* SM */ 219#define IP_PROTO_PTP 123 /* Performance Transparency */ 220#define IP_PROTO_ISIS 124 /* ISIS over IPv4 */ 221#define IP_PROTO_FIRE 125 /* FIRE */ 222#define IP_PROTO_CRTP 126 /* Combat Radio Transport */ 223#define IP_PROTO_CRUDP 127 /* Combat Radio UDP */ 224#define IP_PROTO_SSCOPMCE 128 /* SSCOPMCE */ 225#define IP_PROTO_IPLT 129 /* IPLT */ 226#define IP_PROTO_SPS 130 /* Secure Packet Shield */ 227#define IP_PROTO_PIPE 131 /* Private IP Encap in IP */ 228#define IP_PROTO_SCTP 132 /* Stream Ctrl Transmission */ 229#define IP_PROTO_FC 133 /* Fibre Channel */ 230#define IP_PROTO_RSVPIGN 134 /* RSVP-E2E-IGNORE */ 231#define IP_PROTO_RAW 255 /* Raw IP packets */ 232#define IP_PROTO_RESERVED IP_PROTO_RAW /* Reserved */ 233#define IP_PROTO_MAX 255 234 235/* 236 * Option types (opt_type) - http://www.iana.org/assignments/ip-parameters 237 */ 238#define IP_OPT_CONTROL 0x00 /* control */ 239#define IP_OPT_DEBMEAS 0x40 /* debugging & measurement */ 240#define IP_OPT_COPY 0x80 /* copy into all fragments */ 241#define IP_OPT_RESERVED1 0x20 242#define IP_OPT_RESERVED2 0x60 243 244#define IP_OPT_EOL 0 /* end of option list */ 245#define IP_OPT_NOP 1 /* no operation */ 246#define IP_OPT_SEC (2|IP_OPT_COPY) /* DoD basic security */ 247#define IP_OPT_LSRR (3|IP_OPT_COPY) /* loose source route */ 248#define IP_OPT_TS (4|IP_OPT_DEBMEAS) /* timestamp */ 249#define IP_OPT_ESEC (5|IP_OPT_COPY) /* DoD extended security */ 250#define IP_OPT_CIPSO (6|IP_OPT_COPY) /* commercial security */ 251#define IP_OPT_RR 7 /* record route */ 252#define IP_OPT_SATID (8|IP_OPT_COPY) /* stream ID (obsolete) */ 253#define IP_OPT_SSRR (9|IP_OPT_COPY) /* strict source route */ 254#define IP_OPT_ZSU 10 /* experimental measurement */ 255#define IP_OPT_MTUP 11 /* MTU probe */ 256#define IP_OPT_MTUR 12 /* MTU reply */ 257#define IP_OPT_FINN (13|IP_OPT_COPY|IP_OPT_DEBMEAS) /* exp flow control */ 258#define IP_OPT_VISA (14|IP_OPT_COPY) /* exp access control */ 259#define IP_OPT_ENCODE 15 /* ??? */ 260#define IP_OPT_IMITD (16|IP_OPT_COPY) /* IMI traffic descriptor */ 261#define IP_OPT_EIP (17|IP_OPT_COPY) /* extended IP, RFC 1385 */ 262#define IP_OPT_TR (18|IP_OPT_DEBMEAS) /* traceroute */ 263#define IP_OPT_ADDEXT (19|IP_OPT_COPY) /* IPv7 ext addr, RFC 1475 */ 264#define IP_OPT_RTRALT (20|IP_OPT_COPY) /* router alert, RFC 2113 */ 265#define IP_OPT_SDB (21|IP_OPT_COPY) /* directed bcast, RFC 1770 */ 266#define IP_OPT_NSAPA (22|IP_OPT_COPY) /* NSAP addresses */ 267#define IP_OPT_DPS (23|IP_OPT_COPY) /* dynamic packet state */ 268#define IP_OPT_UMP (24|IP_OPT_COPY) /* upstream multicast */ 269#define IP_OPT_MAX 25 270 271#define IP_OPT_COPIED(o) ((o) & 0x80) 272#define IP_OPT_CLASS(o) ((o) & 0x60) 273#define IP_OPT_NUMBER(o) ((o) & 0x1f) 274#define IP_OPT_TYPEONLY(o) ((o) == IP_OPT_EOL || (o) == IP_OPT_NOP) 275 276/* 277 * Security option data - RFC 791, 3.1 278 */ 279struct ip_opt_data_sec { 280 uint16_t s; /* security */ 281 uint16_t c; /* compartments */ 282 uint16_t h; /* handling restrictions */ 283 uint8_t tcc[3]; /* transmission control code */ 284} __attribute__((__packed__)); 285 286#define IP_OPT_SEC_UNCLASS 0x0000 /* unclassified */ 287#define IP_OPT_SEC_CONFID 0xf135 /* confidential */ 288#define IP_OPT_SEC_EFTO 0x789a /* EFTO */ 289#define IP_OPT_SEC_MMMM 0xbc4d /* MMMM */ 290#define IP_OPT_SEC_PROG 0x5e26 /* PROG */ 291#define IP_OPT_SEC_RESTR 0xaf13 /* restricted */ 292#define IP_OPT_SEC_SECRET 0xd788 /* secret */ 293#define IP_OPT_SEC_TOPSECRET 0x6bc5 /* top secret */ 294 295/* 296 * {Loose Source, Record, Strict Source} Route option data - RFC 791, 3.1 297 */ 298struct ip_opt_data_rr { 299 uint8_t ptr; /* from start of option, >= 4 */ 300 uint32_t iplist __flexarr; /* list of IP addresses */ 301} __attribute__((__packed__)); 302 303/* 304 * Timestamp option data - RFC 791, 3.1 305 */ 306struct ip_opt_data_ts { 307 uint8_t ptr; /* from start of option, >= 5 */ 308#if DNET_BYTESEX == DNET_BIG_ENDIAN 309 uint8_t oflw:4, /* number of IPs skipped */ 310 flg:4; /* address[ / timestamp] flag */ 311#elif DNET_BYTESEX == DNET_LIL_ENDIAN 312 uint8_t flg:4, 313 oflw:4; 314#endif 315 uint32_t ipts __flexarr; /* IP address [/ timestamp] pairs */ 316} __attribute__((__packed__)); 317 318#define IP_OPT_TS_TSONLY 0 /* timestamps only */ 319#define IP_OPT_TS_TSADDR 1 /* IP address / timestamp pairs */ 320#define IP_OPT_TS_PRESPEC 3 /* IP address / zero timestamp pairs */ 321 322/* 323 * Traceroute option data - RFC 1393, 2.2 324 */ 325struct ip_opt_data_tr { 326 uint16_t id; /* ID number */ 327 uint16_t ohc; /* outbound hop count */ 328 uint16_t rhc; /* return hop count */ 329 uint32_t origip; /* originator IP address */ 330} __attribute__((__packed__)); 331 332/* 333 * IP option (following IP header) 334 */ 335struct ip_opt { 336 uint8_t opt_type; /* option type */ 337 uint8_t opt_len; /* option length >= IP_OPT_LEN */ 338 union ip_opt_data { 339 struct ip_opt_data_sec sec; /* IP_OPT_SEC */ 340 struct ip_opt_data_rr rr; /* IP_OPT_{L,S}RR */ 341 struct ip_opt_data_ts ts; /* IP_OPT_TS */ 342 uint16_t satid; /* IP_OPT_SATID */ 343 uint16_t mtu; /* IP_OPT_MTU{P,R} */ 344 struct ip_opt_data_tr tr; /* IP_OPT_TR */ 345 uint32_t addext[2]; /* IP_OPT_ADDEXT */ 346 uint16_t rtralt; /* IP_OPT_RTRALT */ 347 uint32_t sdb[9]; /* IP_OPT_SDB */ 348 uint8_t data8[IP_OPT_LEN_MAX - IP_OPT_LEN]; 349 } opt_data; 350} __attribute__((__packed__)); 351 352#ifndef __GNUC__ 353# pragma pack() 354#endif 355 356/* 357 * Classful addressing 358 */ 359#define IP_CLASSA(i) (((uint32_t)(i) & htonl(0x80000000)) == \ 360 htonl(0x00000000)) 361#define IP_CLASSA_NET (htonl(0xff000000)) 362#define IP_CLASSA_NSHIFT 24 363#define IP_CLASSA_HOST (htonl(0x00ffffff)) 364#define IP_CLASSA_MAX 128 365 366#define IP_CLASSB(i) (((uint32_t)(i) & htonl(0xc0000000)) == \ 367 htonl(0x80000000)) 368#define IP_CLASSB_NET (htonl(0xffff0000)) 369#define IP_CLASSB_NSHIFT 16 370#define IP_CLASSB_HOST (htonl(0x0000ffff)) 371#define IP_CLASSB_MAX 65536 372 373#define IP_CLASSC(i) (((uint32_t)(i) & htonl(0xe0000000)) == \ 374 htonl(0xc0000000)) 375#define IP_CLASSC_NET (htonl(0xffffff00)) 376#define IP_CLASSC_NSHIFT 8 377#define IP_CLASSC_HOST (htonl(0x000000ff)) 378 379#define IP_CLASSD(i) (((uint32_t)(i) & htonl(0xf0000000)) == \ 380 htonl(0xe0000000)) 381/* These ones aren't really net and host fields, but routing needn't know. */ 382#define IP_CLASSD_NET (htonl(0xf0000000)) 383#define IP_CLASSD_NSHIFT 28 384#define IP_CLASSD_HOST (htonl(0x0fffffff)) 385#define IP_MULTICAST(i) IP_CLASSD(i) 386 387#define IP_EXPERIMENTAL(i) (((uint32_t)(i) & htonl(0xf0000000)) == \ 388 htonl(0xf0000000)) 389#define IP_BADCLASS(i) (((uint32_t)(i) & htonl(0xf0000000)) == \ 390 htonl(0xf0000000)) 391#define IP_LOCAL_GROUP(i) (((uint32_t)(i) & htonl(0xffffff00)) == \ 392 htonl(0xe0000000)) 393/* 394 * Reserved addresses 395 */ 396#define IP_ADDR_ANY (htonl(0x00000000)) /* 0.0.0.0 */ 397#define IP_ADDR_BROADCAST (htonl(0xffffffff)) /* 255.255.255.255 */ 398#define IP_ADDR_LOOPBACK (htonl(0x7f000001)) /* 127.0.0.1 */ 399#define IP_ADDR_MCAST_ALL (htonl(0xe0000001)) /* 224.0.0.1 */ 400#define IP_ADDR_MCAST_LOCAL (htonl(0xe00000ff)) /* 224.0.0.225 */ 401 402#define ip_pack_hdr(hdr, tos, len, id, off, ttl, p, src, dst) do { \ 403 struct ip_hdr *ip_pack_p = (struct ip_hdr *)(hdr); \ 404 ip_pack_p->ip_v = 4; ip_pack_p->ip_hl = 5; \ 405 ip_pack_p->ip_tos = tos; ip_pack_p->ip_len = htons(len); \ 406 ip_pack_p->ip_id = htons(id); ip_pack_p->ip_off = htons(off); \ 407 ip_pack_p->ip_ttl = ttl; ip_pack_p->ip_p = p; \ 408 ip_pack_p->ip_src = src; ip_pack_p->ip_dst = dst; \ 409} while (0) 410 411typedef struct ip_handle ip_t; 412 413__BEGIN_DECLS 414ip_t *ip_open(void); 415size_t ip_send(ip_t *i, const void *buf, size_t len); 416ip_t *ip_close(ip_t *i); 417 418char *ip_ntop(const ip_addr_t *ip, char *dst, size_t len); 419int ip_pton(const char *src, ip_addr_t *dst); 420char *ip_ntoa(const ip_addr_t *ip); 421#define ip_aton ip_pton 422 423size_t ip_add_option(void *buf, size_t len, 424 int proto, const void *optbuf, size_t optlen); 425void ip_checksum(void *buf, size_t len); 426 427inline int 428ip_cksum_add(const void *buf, size_t len, int cksum) 429{ 430 uint16_t *sp = (uint16_t *)buf; 431 int sn; 432 433 sn = len / 2; 434 435 do { 436 cksum += *sp++; 437 } while (--sn > 0); 438 if (len & 1) 439 cksum += htons(*(u_char *)sp << 8); 440 441 return (cksum); 442} 443 444inline uint16_t 445ip_cksum_carry(int x) 446{ 447 x = (x >> 16) + (x & 0xffff); 448 return ~(x + (x >> 16)) & 0xffff; 449} 450 451__END_DECLS 452 453#endif /* DNET_IP_H */ 454