Current Path : /usr/src/lib/libstand/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //usr/src/lib/libstand/udp.c |
/* Taken from $NetBSD: net.c,v 1.20 1997/12/26 22:41:30 scottr Exp $ */ /* * Copyright (c) 1992 Regents of the University of California. * All rights reserved. * * This software was developed by the Computer Systems Engineering group * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and * contributed to Berkeley. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL) */ #include <sys/cdefs.h> __FBSDID("$FreeBSD: release/9.1.0/lib/libstand/udp.c 221364 2011-05-03 07:39:54Z rodrigc $"); #include <sys/param.h> #include <sys/socket.h> #include <string.h> #include <net/if.h> #include <netinet/in.h> #include <netinet/if_ether.h> #include <netinet/in_systm.h> #include <netinet/in_pcb.h> #include <netinet/ip.h> #include <netinet/ip_var.h> #include <netinet/udp.h> #include <netinet/udp_var.h> #include "stand.h" #include "net.h" /* Caller must leave room for ethernet, ip and udp headers in front!! */ ssize_t sendudp(d, pkt, len) struct iodesc *d; void *pkt; size_t len; { ssize_t cc; struct ip *ip; struct udphdr *uh; u_char *ea; #ifdef NET_DEBUG if (debug) { printf("sendudp: d=%lx called.\n", (long)d); if (d) { printf("saddr: %s:%d", inet_ntoa(d->myip), ntohs(d->myport)); printf(" daddr: %s:%d\n", inet_ntoa(d->destip), ntohs(d->destport)); } } #endif uh = (struct udphdr *)pkt - 1; ip = (struct ip *)uh - 1; len += sizeof(*ip) + sizeof(*uh); bzero(ip, sizeof(*ip) + sizeof(*uh)); ip->ip_v = IPVERSION; /* half-char */ ip->ip_hl = sizeof(*ip) >> 2; /* half-char */ ip->ip_len = htons(len); ip->ip_p = IPPROTO_UDP; /* char */ ip->ip_ttl = IPDEFTTL; /* char */ ip->ip_src = d->myip; ip->ip_dst = d->destip; ip->ip_sum = in_cksum(ip, sizeof(*ip)); /* short, but special */ uh->uh_sport = d->myport; uh->uh_dport = d->destport; uh->uh_ulen = htons(len - sizeof(*ip)); #ifndef UDP_NO_CKSUM { struct udpiphdr *ui; struct ip tip; /* Calculate checksum (must save and restore ip header) */ tip = *ip; ui = (struct udpiphdr *)ip; bzero(&ui->ui_x1, sizeof(ui->ui_x1)); ui->ui_len = uh->uh_ulen; uh->uh_sum = in_cksum(ui, len); *ip = tip; } #endif if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 || netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask)) ea = arpwhohas(d, ip->ip_dst); else ea = arpwhohas(d, gateip); cc = sendether(d, ip, len, ea, ETHERTYPE_IP); if (cc == -1) return (-1); if (cc != len) panic("sendudp: bad write (%zd != %zd)", cc, len); return (cc - (sizeof(*ip) + sizeof(*uh))); } /* * Receive a UDP packet and validate it is for us. * Caller leaves room for the headers (Ether, IP, UDP) */ ssize_t readudp(d, pkt, len, tleft) struct iodesc *d; void *pkt; size_t len; time_t tleft; { ssize_t n; size_t hlen; struct ip *ip; struct udphdr *uh; u_int16_t etype; /* host order */ #ifdef NET_DEBUG if (debug) printf("readudp: called\n"); #endif uh = (struct udphdr *)pkt - 1; ip = (struct ip *)uh - 1; n = readether(d, ip, len + sizeof(*ip) + sizeof(*uh), tleft, &etype); if (n == -1 || n < sizeof(*ip) + sizeof(*uh)) return -1; /* Ethernet address checks now in readether() */ /* Need to respond to ARP requests. */ if (etype == ETHERTYPE_ARP) { struct arphdr *ah = (void *)ip; if (ah->ar_op == htons(ARPOP_REQUEST)) { /* Send ARP reply */ arp_reply(d, ah); } return -1; } if (etype != ETHERTYPE_IP) { #ifdef NET_DEBUG if (debug) printf("readudp: not IP. ether_type=%x\n", etype); #endif return -1; } /* Check ip header */ if (ip->ip_v != IPVERSION || ip->ip_p != IPPROTO_UDP) { /* half char */ #ifdef NET_DEBUG if (debug) printf("readudp: IP version or not UDP. ip_v=%d ip_p=%d\n", ip->ip_v, ip->ip_p); #endif return -1; } hlen = ip->ip_hl << 2; if (hlen < sizeof(*ip) || in_cksum(ip, hlen) != 0) { #ifdef NET_DEBUG if (debug) printf("readudp: short hdr or bad cksum.\n"); #endif return -1; } if (n < ntohs(ip->ip_len)) { #ifdef NET_DEBUG if (debug) printf("readudp: bad length %d < %d.\n", (int)n, ntohs(ip->ip_len)); #endif return -1; } if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) { #ifdef NET_DEBUG if (debug) { printf("readudp: bad saddr %s != ", inet_ntoa(d->myip)); printf("%s\n", inet_ntoa(ip->ip_dst)); } #endif return -1; } /* If there were ip options, make them go away */ if (hlen != sizeof(*ip)) { bcopy(((u_char *)ip) + hlen, uh, len - hlen); ip->ip_len = htons(sizeof(*ip)); n -= hlen - sizeof(*ip); } if (uh->uh_dport != d->myport) { #ifdef NET_DEBUG if (debug) printf("readudp: bad dport %d != %d\n", d->myport, ntohs(uh->uh_dport)); #endif return -1; } #ifndef UDP_NO_CKSUM if (uh->uh_sum) { struct udpiphdr *ui; struct ip tip; n = ntohs(uh->uh_ulen) + sizeof(*ip); if (n > RECV_SIZE - ETHER_SIZE) { printf("readudp: huge packet, udp len %d\n", (int)n); return -1; } /* Check checksum (must save and restore ip header) */ tip = *ip; ui = (struct udpiphdr *)ip; bzero(&ui->ui_x1, sizeof(ui->ui_x1)); ui->ui_len = uh->uh_ulen; if (in_cksum(ui, n) != 0) { #ifdef NET_DEBUG if (debug) printf("readudp: bad cksum\n"); #endif *ip = tip; return -1; } *ip = tip; } #endif if (ntohs(uh->uh_ulen) < sizeof(*uh)) { #ifdef NET_DEBUG if (debug) printf("readudp: bad udp len %d < %d\n", ntohs(uh->uh_ulen), (int)sizeof(*uh)); #endif return -1; } n = (n > (ntohs(uh->uh_ulen) - sizeof(*uh))) ? ntohs(uh->uh_ulen) - sizeof(*uh) : n; return (n); }