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Diffstat (limited to 'ext/dnet/ip.h')
| -rw-r--r-- | ext/dnet/ip.h | 487 |
1 files changed, 487 insertions, 0 deletions
diff --git a/ext/dnet/ip.h b/ext/dnet/ip.h new file mode 100644 index 000000000..95b7718fb --- /dev/null +++ b/ext/dnet/ip.h @@ -0,0 +1,487 @@ +/* + * ip.h + * + * Internet Protocol (RFC 791). + * + * Copyright (c) 2000 Dug Song <dugsong@monkey.org> + * + * $Id: ip.h,v 1.23 2003/03/16 17:39:17 dugsong Exp $ + */ + +#ifndef DNET_IP_H +#define DNET_IP_H + +#define IP_ADDR_LEN 4 /* IP address length */ +#define IP_ADDR_BITS 32 /* IP address bits */ + +#define IP_HDR_LEN 20 /* base IP header length */ +#define IP_OPT_LEN 2 /* base IP option length */ +#define IP_OPT_LEN_MAX 40 +#define IP_HDR_LEN_MAX (IP_HDR_LEN + IP_OPT_LEN_MAX) + +#define IP_LEN_MAX 65535 +#define IP_LEN_MIN IP_HDR_LEN + +typedef uint32_t ip_addr_t; + +#ifndef __GNUC__ +# define __attribute__(x) +# pragma pack(1) +#endif + +/* + * IP header, without options + */ +struct ip_hdr { +#if DNET_BYTESEX == DNET_BIG_ENDIAN + uint8_t ip_v:4, /* version */ + ip_hl:4; /* header length (incl any options) */ +#elif DNET_BYTESEX == DNET_LIL_ENDIAN + uint8_t ip_hl:4, + ip_v:4; +#else +# error "need to include <dnet.h>" +#endif + uint8_t ip_tos; /* type of service */ + uint16_t ip_len; /* total length (incl header) */ + uint16_t ip_id; /* identification */ + uint16_t ip_off; /* fragment offset and flags */ + uint8_t ip_ttl; /* time to live */ + uint8_t ip_p; /* protocol */ + uint16_t ip_sum; /* checksum */ + ip_addr_t ip_src; /* source address */ + ip_addr_t ip_dst; /* destination address */ +}; + +/* + * Type of service (ip_tos), RFC 1349 ("obsoleted by RFC 2474") + */ +#define IP_TOS_DEFAULT 0x00 /* default */ +#define IP_TOS_LOWDELAY 0x10 /* low delay */ +#define IP_TOS_THROUGHPUT 0x08 /* high throughput */ +#define IP_TOS_RELIABILITY 0x04 /* high reliability */ +#define IP_TOS_LOWCOST 0x02 /* low monetary cost - XXX */ +#define IP_TOS_ECT 0x02 /* ECN-capable transport */ +#define IP_TOS_CE 0x01 /* congestion experienced */ + +/* + * IP precedence (high 3 bits of ip_tos), hopefully unused + */ +#define IP_TOS_PREC_ROUTINE 0x00 +#define IP_TOS_PREC_PRIORITY 0x20 +#define IP_TOS_PREC_IMMEDIATE 0x40 +#define IP_TOS_PREC_FLASH 0x60 +#define IP_TOS_PREC_FLASHOVERRIDE 0x80 +#define IP_TOS_PREC_CRITIC_ECP 0xa0 +#define IP_TOS_PREC_INTERNETCONTROL 0xc0 +#define IP_TOS_PREC_NETCONTROL 0xe0 + +/* + * Fragmentation flags (ip_off) + */ +#define IP_RF 0x8000 /* reserved */ +#define IP_DF 0x4000 /* don't fragment */ +#define IP_MF 0x2000 /* more fragments (not last frag) */ +#define IP_OFFMASK 0x1fff /* mask for fragment offset */ + +/* + * Time-to-live (ip_ttl), seconds + */ +#define IP_TTL_DEFAULT 64 /* default ttl, RFC 1122, RFC 1340 */ +#define IP_TTL_MAX 255 /* maximum ttl */ + +/* + * Protocol (ip_p) - http://www.iana.org/assignments/protocol-numbers + */ +#define IP_PROTO_IP 0 /* dummy for IP */ +#define IP_PROTO_HOPOPTS IP_PROTO_IP /* IPv6 hop-by-hop options */ +#define IP_PROTO_ICMP 1 /* ICMP */ +#define IP_PROTO_IGMP 2 /* IGMP */ +#define IP_PROTO_GGP 3 /* gateway-gateway protocol */ +#define IP_PROTO_IPIP 4 /* IP in IP */ +#define IP_PROTO_ST 5 /* ST datagram mode */ +#define IP_PROTO_TCP 6 /* TCP */ +#define IP_PROTO_CBT 7 /* CBT */ +#define IP_PROTO_EGP 8 /* exterior gateway protocol */ +#define IP_PROTO_IGP 9 /* interior gateway protocol */ +#define IP_PROTO_BBNRCC 10 /* BBN RCC monitoring */ +#define IP_PROTO_NVP 11 /* Network Voice Protocol */ +#define IP_PROTO_PUP 12 /* PARC universal packet */ +#define IP_PROTO_ARGUS 13 /* ARGUS */ +#define IP_PROTO_EMCON 14 /* EMCON */ +#define IP_PROTO_XNET 15 /* Cross Net Debugger */ +#define IP_PROTO_CHAOS 16 /* Chaos */ +#define IP_PROTO_UDP 17 /* UDP */ +#define IP_PROTO_MUX 18 /* multiplexing */ +#define IP_PROTO_DCNMEAS 19 /* DCN measurement */ +#define IP_PROTO_HMP 20 /* Host Monitoring Protocol */ +#define IP_PROTO_PRM 21 /* Packet Radio Measurement */ +#define IP_PROTO_IDP 22 /* Xerox NS IDP */ +#define IP_PROTO_TRUNK1 23 /* Trunk-1 */ +#define IP_PROTO_TRUNK2 24 /* Trunk-2 */ +#define IP_PROTO_LEAF1 25 /* Leaf-1 */ +#define IP_PROTO_LEAF2 26 /* Leaf-2 */ +#define IP_PROTO_RDP 27 /* "Reliable Datagram" proto */ +#define IP_PROTO_IRTP 28 /* Inet Reliable Transaction */ +#define IP_PROTO_TP 29 /* ISO TP class 4 */ +#define IP_PROTO_NETBLT 30 /* Bulk Data Transfer */ +#define IP_PROTO_MFPNSP 31 /* MFE Network Services */ +#define IP_PROTO_MERITINP 32 /* Merit Internodal Protocol */ +#define IP_PROTO_SEP 33 /* Sequential Exchange proto */ +#define IP_PROTO_3PC 34 /* Third Party Connect proto */ +#define IP_PROTO_IDPR 35 /* Interdomain Policy Route */ +#define IP_PROTO_XTP 36 /* Xpress Transfer Protocol */ +#define IP_PROTO_DDP 37 /* Datagram Delivery Proto */ +#define IP_PROTO_CMTP 38 /* IDPR Ctrl Message Trans */ +#define IP_PROTO_TPPP 39 /* TP++ Transport Protocol */ +#define IP_PROTO_IL 40 /* IL Transport Protocol */ +#define IP_PROTO_IPV6 41 /* IPv6 */ +#define IP_PROTO_SDRP 42 /* Source Demand Routing */ +#define IP_PROTO_ROUTING 43 /* IPv6 routing header */ +#define IP_PROTO_FRAGMENT 44 /* IPv6 fragmentation header */ +#define IP_PROTO_RSVP 46 /* Reservation protocol */ +#define IP_PROTO_GRE 47 /* General Routing Encap */ +#define IP_PROTO_MHRP 48 /* Mobile Host Routing */ +#define IP_PROTO_ENA 49 /* ENA */ +#define IP_PROTO_ESP 50 /* Encap Security Payload */ +#define IP_PROTO_AH 51 /* Authentication Header */ +#define IP_PROTO_INLSP 52 /* Integated Net Layer Sec */ +#define IP_PROTO_SWIPE 53 /* SWIPE */ +#define IP_PROTO_NARP 54 /* NBMA Address Resolution */ +#define IP_PROTO_MOBILE 55 /* Mobile IP, RFC 2004 */ +#define IP_PROTO_TLSP 56 /* Transport Layer Security */ +#define IP_PROTO_SKIP 57 /* SKIP */ +#define IP_PROTO_ICMPV6 58 /* ICMP for IPv6 */ +#define IP_PROTO_NONE 59 /* IPv6 no next header */ +#define IP_PROTO_DSTOPTS 60 /* IPv6 destination options */ +#define IP_PROTO_ANYHOST 61 /* any host internal proto */ +#define IP_PROTO_CFTP 62 /* CFTP */ +#define IP_PROTO_ANYNET 63 /* any local network */ +#define IP_PROTO_EXPAK 64 /* SATNET and Backroom EXPAK */ +#define IP_PROTO_KRYPTOLAN 65 /* Kryptolan */ +#define IP_PROTO_RVD 66 /* MIT Remote Virtual Disk */ +#define IP_PROTO_IPPC 67 /* Inet Pluribus Packet Core */ +#define IP_PROTO_DISTFS 68 /* any distributed fs */ +#define IP_PROTO_SATMON 69 /* SATNET Monitoring */ +#define IP_PROTO_VISA 70 /* VISA Protocol */ +#define IP_PROTO_IPCV 71 /* Inet Packet Core Utility */ +#define IP_PROTO_CPNX 72 /* Comp Proto Net Executive */ +#define IP_PROTO_CPHB 73 /* Comp Protocol Heart Beat */ +#define IP_PROTO_WSN 74 /* Wang Span Network */ +#define IP_PROTO_PVP 75 /* Packet Video Protocol */ +#define IP_PROTO_BRSATMON 76 /* Backroom SATNET Monitor */ +#define IP_PROTO_SUNND 77 /* SUN ND Protocol */ +#define IP_PROTO_WBMON 78 /* WIDEBAND Monitoring */ +#define IP_PROTO_WBEXPAK 79 /* WIDEBAND EXPAK */ +#define IP_PROTO_EON 80 /* ISO CNLP */ +#define IP_PROTO_VMTP 81 /* Versatile Msg Transport*/ +#define IP_PROTO_SVMTP 82 /* Secure VMTP */ +#define IP_PROTO_VINES 83 /* VINES */ +#define IP_PROTO_TTP 84 /* TTP */ +#define IP_PROTO_NSFIGP 85 /* NSFNET-IGP */ +#define IP_PROTO_DGP 86 /* Dissimilar Gateway Proto */ +#define IP_PROTO_TCF 87 /* TCF */ +#define IP_PROTO_EIGRP 88 /* EIGRP */ +#define IP_PROTO_OSPF 89 /* Open Shortest Path First */ +#define IP_PROTO_SPRITERPC 90 /* Sprite RPC Protocol */ +#define IP_PROTO_LARP 91 /* Locus Address Resolution */ +#define IP_PROTO_MTP 92 /* Multicast Transport Proto */ +#define IP_PROTO_AX25 93 /* AX.25 Frames */ +#define IP_PROTO_IPIPENCAP 94 /* yet-another IP encap */ +#define IP_PROTO_MICP 95 /* Mobile Internet Ctrl */ +#define IP_PROTO_SCCSP 96 /* Semaphore Comm Sec Proto */ +#define IP_PROTO_ETHERIP 97 /* Ethernet in IPv4 */ +#define IP_PROTO_ENCAP 98 /* encapsulation header */ +#define IP_PROTO_ANYENC 99 /* private encryption scheme */ +#define IP_PROTO_GMTP 100 /* GMTP */ +#define IP_PROTO_IFMP 101 /* Ipsilon Flow Mgmt Proto */ +#define IP_PROTO_PNNI 102 /* PNNI over IP */ +#define IP_PROTO_PIM 103 /* Protocol Indep Multicast */ +#define IP_PROTO_ARIS 104 /* ARIS */ +#define IP_PROTO_SCPS 105 /* SCPS */ +#define IP_PROTO_QNX 106 /* QNX */ +#define IP_PROTO_AN 107 /* Active Networks */ +#define IP_PROTO_IPCOMP 108 /* IP Payload Compression */ +#define IP_PROTO_SNP 109 /* Sitara Networks Protocol */ +#define IP_PROTO_COMPAQPEER 110 /* Compaq Peer Protocol */ +#define IP_PROTO_IPXIP 111 /* IPX in IP */ +#define IP_PROTO_VRRP 112 /* Virtual Router Redundancy */ +#define IP_PROTO_PGM 113 /* PGM Reliable Transport */ +#define IP_PROTO_ANY0HOP 114 /* 0-hop protocol */ +#define IP_PROTO_L2TP 115 /* Layer 2 Tunneling Proto */ +#define IP_PROTO_DDX 116 /* D-II Data Exchange (DDX) */ +#define IP_PROTO_IATP 117 /* Interactive Agent Xfer */ +#define IP_PROTO_STP 118 /* Schedule Transfer Proto */ +#define IP_PROTO_SRP 119 /* SpectraLink Radio Proto */ +#define IP_PROTO_UTI 120 /* UTI */ +#define IP_PROTO_SMP 121 /* Simple Message Protocol */ +#define IP_PROTO_SM 122 /* SM */ +#define IP_PROTO_PTP 123 /* Performance Transparency */ +#define IP_PROTO_ISIS 124 /* ISIS over IPv4 */ +#define IP_PROTO_FIRE 125 /* FIRE */ +#define IP_PROTO_CRTP 126 /* Combat Radio Transport */ +#define IP_PROTO_CRUDP 127 /* Combat Radio UDP */ +#define IP_PROTO_SSCOPMCE 128 /* SSCOPMCE */ +#define IP_PROTO_IPLT 129 /* IPLT */ +#define IP_PROTO_SPS 130 /* Secure Packet Shield */ +#define IP_PROTO_PIPE 131 /* Private IP Encap in IP */ +#define IP_PROTO_SCTP 132 /* Stream Ctrl Transmission */ +#define IP_PROTO_FC 133 /* Fibre Channel */ +#define IP_PROTO_RSVPIGN 134 /* RSVP-E2E-IGNORE */ +#define IP_PROTO_RAW 255 /* Raw IP packets */ +#define IP_PROTO_RESERVED IP_PROTO_RAW /* Reserved */ +#define IP_PROTO_MAX 255 + +/* + * Option types (opt_type) - http://www.iana.org/assignments/ip-parameters + */ +#define IP_OPT_CONTROL 0x00 /* control */ +#define IP_OPT_DEBMEAS 0x40 /* debugging & measurement */ +#define IP_OPT_COPY 0x80 /* copy into all fragments */ +#define IP_OPT_RESERVED1 0x20 +#define IP_OPT_RESERVED2 0x60 + +#define IP_OPT_EOL 0 /* end of option list */ +#define IP_OPT_NOP 1 /* no operation */ +#define IP_OPT_SEC (2|IP_OPT_COPY) /* DoD basic security */ +#define IP_OPT_LSRR (3|IP_OPT_COPY) /* loose source route */ +#define IP_OPT_TS (4|IP_OPT_DEBMEAS) /* timestamp */ +#define IP_OPT_ESEC (5|IP_OPT_COPY) /* DoD extended security */ +#define IP_OPT_CIPSO (6|IP_OPT_COPY) /* commercial security */ +#define IP_OPT_RR 7 /* record route */ +#define IP_OPT_SATID (8|IP_OPT_COPY) /* stream ID (obsolete) */ +#define IP_OPT_SSRR (9|IP_OPT_COPY) /* strict source route */ +#define IP_OPT_ZSU 10 /* experimental measurement */ +#define IP_OPT_MTUP 11 /* MTU probe */ +#define IP_OPT_MTUR 12 /* MTU reply */ +#define IP_OPT_FINN (13|IP_OPT_COPY|IP_OPT_DEBMEAS) /* exp flow control */ +#define IP_OPT_VISA (14|IP_OPT_COPY) /* exp access control */ +#define IP_OPT_ENCODE 15 /* ??? */ +#define IP_OPT_IMITD (16|IP_OPT_COPY) /* IMI traffic descriptor */ +#define IP_OPT_EIP (17|IP_OPT_COPY) /* extended IP, RFC 1385 */ +#define IP_OPT_TR (18|IP_OPT_DEBMEAS) /* traceroute */ +#define IP_OPT_ADDEXT (19|IP_OPT_COPY) /* IPv7 ext addr, RFC 1475 */ +#define IP_OPT_RTRALT (20|IP_OPT_COPY) /* router alert, RFC 2113 */ +#define IP_OPT_SDB (21|IP_OPT_COPY) /* directed bcast, RFC 1770 */ +#define IP_OPT_NSAPA (22|IP_OPT_COPY) /* NSAP addresses */ +#define IP_OPT_DPS (23|IP_OPT_COPY) /* dynamic packet state */ +#define IP_OPT_UMP (24|IP_OPT_COPY) /* upstream multicast */ +#define IP_OPT_MAX 25 + +#define IP_OPT_COPIED(o) ((o) & 0x80) +#define IP_OPT_CLASS(o) ((o) & 0x60) +#define IP_OPT_NUMBER(o) ((o) & 0x1f) +#define IP_OPT_TYPEONLY(o) ((o) == IP_OPT_EOL || (o) == IP_OPT_NOP) + +/* + * Security option data - RFC 791, 3.1 + */ +struct ip_opt_data_sec { + uint16_t s; /* security */ + uint16_t c; /* compartments */ + uint16_t h; /* handling restrictions */ + uint8_t tcc[3]; /* transmission control code */ +} __attribute__((__packed__)); + +#define IP_OPT_SEC_UNCLASS 0x0000 /* unclassified */ +#define IP_OPT_SEC_CONFID 0xf135 /* confidential */ +#define IP_OPT_SEC_EFTO 0x789a /* EFTO */ +#define IP_OPT_SEC_MMMM 0xbc4d /* MMMM */ +#define IP_OPT_SEC_PROG 0x5e26 /* PROG */ +#define IP_OPT_SEC_RESTR 0xaf13 /* restricted */ +#define IP_OPT_SEC_SECRET 0xd788 /* secret */ +#define IP_OPT_SEC_TOPSECRET 0x6bc5 /* top secret */ + +/* + * {Loose Source, Record, Strict Source} Route option data - RFC 791, 3.1 + */ +struct ip_opt_data_rr { + uint8_t ptr; /* from start of option, >= 4 */ + uint32_t iplist __flexarr; /* list of IP addresses */ +} __attribute__((__packed__)); + +/* + * Timestamp option data - RFC 791, 3.1 + */ +struct ip_opt_data_ts { + uint8_t ptr; /* from start of option, >= 5 */ +#if DNET_BYTESEX == DNET_BIG_ENDIAN + uint8_t oflw:4, /* number of IPs skipped */ + flg:4; /* address[ / timestamp] flag */ +#elif DNET_BYTESEX == DNET_LIL_ENDIAN + uint8_t flg:4, + oflw:4; +#endif + uint32_t ipts __flexarr; /* IP address [/ timestamp] pairs */ +} __attribute__((__packed__)); + +#define IP_OPT_TS_TSONLY 0 /* timestamps only */ +#define IP_OPT_TS_TSADDR 1 /* IP address / timestamp pairs */ +#define IP_OPT_TS_PRESPEC 3 /* IP address / zero timestamp pairs */ + +/* + * Traceroute option data - RFC 1393, 2.2 + */ +struct ip_opt_data_tr { + uint16_t id; /* ID number */ + uint16_t ohc; /* outbound hop count */ + uint16_t rhc; /* return hop count */ + uint32_t origip; /* originator IP address */ +} __attribute__((__packed__)); + +/* + * IP option (following IP header) + */ +struct ip_opt { + uint8_t opt_type; /* option type */ + uint8_t opt_len; /* option length >= IP_OPT_LEN */ + union ip_opt_data { + struct ip_opt_data_sec sec; /* IP_OPT_SEC */ + struct ip_opt_data_rr rr; /* IP_OPT_{L,S}RR */ + struct ip_opt_data_ts ts; /* IP_OPT_TS */ + uint16_t satid; /* IP_OPT_SATID */ + uint16_t mtu; /* IP_OPT_MTU{P,R} */ + struct ip_opt_data_tr tr; /* IP_OPT_TR */ + uint32_t addext[2]; /* IP_OPT_ADDEXT */ + uint16_t rtralt; /* IP_OPT_RTRALT */ + uint32_t sdb[9]; /* IP_OPT_SDB */ + uint8_t data8[IP_OPT_LEN_MAX - IP_OPT_LEN]; + } opt_data; +} __attribute__((__packed__)); + +#ifndef __GNUC__ +# pragma pack() +#endif + +/* + * Classful addressing + */ +#define IP_CLASSA(i) (((uint32_t)(i) & htonl(0x80000000)) == \ + htonl(0x00000000)) +#define IP_CLASSA_NET (htonl(0xff000000)) +#define IP_CLASSA_NSHIFT 24 +#define IP_CLASSA_HOST (htonl(0x00ffffff)) +#define IP_CLASSA_MAX 128 + +#define IP_CLASSB(i) (((uint32_t)(i) & htonl(0xc0000000)) == \ + htonl(0x80000000)) +#define IP_CLASSB_NET (htonl(0xffff0000)) +#define IP_CLASSB_NSHIFT 16 +#define IP_CLASSB_HOST (htonl(0x0000ffff)) +#define IP_CLASSB_MAX 65536 + +#define IP_CLASSC(i) (((uint32_t)(i) & htonl(0xe0000000)) == \ + htonl(0xc0000000)) +#define IP_CLASSC_NET (htonl(0xffffff00)) +#define IP_CLASSC_NSHIFT 8 +#define IP_CLASSC_HOST (htonl(0x000000ff)) + +#define IP_CLASSD(i) (((uint32_t)(i) & htonl(0xf0000000)) == \ + htonl(0xe0000000)) +/* These ones aren't really net and host fields, but routing needn't know. */ +#define IP_CLASSD_NET (htonl(0xf0000000)) +#define IP_CLASSD_NSHIFT 28 +#define IP_CLASSD_HOST (htonl(0x0fffffff)) +#define IP_MULTICAST(i) IP_CLASSD(i) + +#define IP_EXPERIMENTAL(i) (((uint32_t)(i) & htonl(0xf0000000)) == \ + htonl(0xf0000000)) +#define IP_BADCLASS(i) (((uint32_t)(i) & htonl(0xf0000000)) == \ + htonl(0xf0000000)) +#define IP_LOCAL_GROUP(i) (((uint32_t)(i) & htonl(0xffffff00)) == \ + htonl(0xe0000000)) +/* + * Reserved addresses + */ +#define IP_ADDR_ANY (htonl(0x00000000)) /* 0.0.0.0 */ +#define IP_ADDR_BROADCAST (htonl(0xffffffff)) /* 255.255.255.255 */ +#define IP_ADDR_LOOPBACK (htonl(0x7f000001)) /* 127.0.0.1 */ +#define IP_ADDR_MCAST_ALL (htonl(0xe0000001)) /* 224.0.0.1 */ +#define IP_ADDR_MCAST_LOCAL (htonl(0xe00000ff)) /* 224.0.0.225 */ + +#define ip_pack_hdr(hdr, tos, len, id, off, ttl, p, src, dst) do { \ + struct ip_hdr *ip_pack_p = (struct ip_hdr *)(hdr); \ + ip_pack_p->ip_v = 4; ip_pack_p->ip_hl = 5; \ + ip_pack_p->ip_tos = tos; ip_pack_p->ip_len = htons(len); \ + ip_pack_p->ip_id = htons(id); ip_pack_p->ip_off = htons(off); \ + ip_pack_p->ip_ttl = ttl; ip_pack_p->ip_p = p; \ + ip_pack_p->ip_src = src; ip_pack_p->ip_dst = dst; \ +} while (0) + +typedef struct ip_handle ip_t; + +__BEGIN_DECLS +ip_t *ip_open(void); +size_t ip_send(ip_t *i, const void *buf, size_t len); +ip_t *ip_close(ip_t *i); + +char *ip_ntop(const ip_addr_t *ip, char *dst, size_t len); +int ip_pton(const char *src, ip_addr_t *dst); +char *ip_ntoa(const ip_addr_t *ip); +#define ip_aton ip_pton + +size_t ip_add_option(void *buf, size_t len, + int proto, const void *optbuf, size_t optlen); +void ip_checksum(void *buf, size_t len); + +inline int +ip_cksum_add(const void *buf, size_t len, int cksum) +{ + uint16_t *sp = (uint16_t *)buf; + int n, sn; + + sn = len / 2; + n = (sn + 15) / 16; + + /* XXX - unroll loop using Duff's device. */ + switch (sn % 16) { + case 0: do { + cksum += *sp++; + case 15: + cksum += *sp++; + case 14: + cksum += *sp++; + case 13: + cksum += *sp++; + case 12: + cksum += *sp++; + case 11: + cksum += *sp++; + case 10: + cksum += *sp++; + case 9: + cksum += *sp++; + case 8: + cksum += *sp++; + case 7: + cksum += *sp++; + case 6: + cksum += *sp++; + case 5: + cksum += *sp++; + case 4: + cksum += *sp++; + case 3: + cksum += *sp++; + case 2: + cksum += *sp++; + case 1: + cksum += *sp++; + } while (--n > 0); + } + if (len & 1) + cksum += htons(*(u_char *)sp << 8); + + return (cksum); +} + +inline uint16_t +ip_cksum_carry(int x) +{ + x = (x >> 16) + (x & 0xffff); + return ~(x + (x >> 16)) & 0xffff; +} + +__END_DECLS + +#endif /* DNET_IP_H */ |