1 /* Taken from $NetBSD: net.c,v 1.20 1997/12/26 22:41:30 scottr Exp $ */ 2 3 /* 4 * Copyright (c) 1992 Regents of the University of California. 5 * All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL) 36 */ 37 38 #include <sys/cdefs.h> 39 40 #include <sys/param.h> 41 #include <sys/socket.h> 42 43 #include <string.h> 44 45 #include <net/if.h> 46 #include <netinet/in.h> 47 #include <netinet/if_ether.h> 48 #include <netinet/in_systm.h> 49 50 #include <netinet/ip.h> 51 #include <netinet/ip_var.h> 52 #include <netinet/udp.h> 53 #include <netinet/udp_var.h> 54 55 #include "stand.h" 56 #include "net.h" 57 58 /* Caller must leave room for ethernet, ip and udp headers in front!! */ 59 ssize_t 60 sendudp(struct iodesc *d, void *pkt, size_t len) 61 { 62 ssize_t cc; 63 struct udpiphdr *ui; 64 struct udphdr *uh; 65 66 #ifdef NET_DEBUG 67 if (debug) { 68 printf("sendudp: d=%lx called.\n", (long)d); 69 if (d) { 70 printf("saddr: %s:%d", 71 inet_ntoa(d->myip), ntohs(d->myport)); 72 printf(" daddr: %s:%d\n", 73 inet_ntoa(d->destip), ntohs(d->destport)); 74 } 75 } 76 #endif 77 78 ui = (struct udpiphdr *)pkt - 1; 79 bzero(ui, sizeof (*ui)); 80 81 uh = (struct udphdr *)pkt - 1; 82 len += sizeof (*uh); 83 84 uh->uh_sport = d->myport; 85 uh->uh_dport = d->destport; 86 uh->uh_ulen = htons(len); 87 88 ui->ui_pr = IPPROTO_UDP; 89 ui->ui_len = uh->uh_ulen; 90 ui->ui_src = d->myip; 91 ui->ui_dst = d->destip; 92 93 #ifndef UDP_NO_CKSUM 94 uh->uh_sum = in_cksum(ui, len + sizeof (struct ip)); 95 #endif 96 97 cc = sendip(d, uh, len, IPPROTO_UDP); 98 if (cc == -1) 99 return (-1); 100 if (cc != len) 101 panic("sendudp: bad write (%zd != %zd)", cc, len); 102 return (cc - sizeof (*uh)); 103 } 104 105 /* 106 * Receive a UDP packet and validate it is for us. 107 */ 108 ssize_t 109 readudp(struct iodesc *d, void **pkt, void **payload, time_t tleft) 110 { 111 ssize_t n; 112 struct udphdr *uh; 113 void *ptr; 114 115 #ifdef NET_DEBUG 116 if (debug) 117 printf("readudp: called\n"); 118 #endif 119 120 uh = NULL; 121 ptr = NULL; 122 n = readip(d, &ptr, (void **)&uh, tleft, IPPROTO_UDP); 123 if (n == -1 || n < sizeof (*uh) || n != ntohs(uh->uh_ulen)) { 124 free(ptr); 125 return (-1); 126 } 127 128 if (uh->uh_dport != d->myport) { 129 #ifdef NET_DEBUG 130 if (debug) 131 printf("readudp: bad dport %d != %d\n", 132 d->myport, ntohs(uh->uh_dport)); 133 #endif 134 free(ptr); 135 return (-1); 136 } 137 138 #ifndef UDP_NO_CKSUM 139 if (uh->uh_sum) { 140 struct udpiphdr *ui; 141 void *ip; 142 struct ip tip; 143 144 n = ntohs(uh->uh_ulen) + sizeof (struct ip); 145 146 /* 147 * Check checksum (must save and restore ip header). 148 * Note we do use void *ip here to make gcc to stop 149 * complaining about possibly unaligned pointer values. 150 * We do allocate buffer in pxe.c/efinet.c and care is 151 * taken to get headers aligned properly. 152 */ 153 ip = (struct ip *)uh - 1; 154 tip = *(struct ip *)ip; 155 ui = ip; 156 bzero(&ui->ui_x1, sizeof (ui->ui_x1)); 157 ui->ui_len = uh->uh_ulen; 158 if (in_cksum(ui, n) != 0) { 159 #ifdef NET_DEBUG 160 if (debug) 161 printf("readudp: bad cksum\n"); 162 #endif 163 free(ptr); 164 return (-1); 165 } 166 *(struct ip *)ip = tip; 167 } 168 #endif 169 if (ntohs(uh->uh_ulen) < sizeof (*uh)) { 170 #ifdef NET_DEBUG 171 if (debug) 172 printf("readudp: bad udp len %d < %d\n", 173 ntohs(uh->uh_ulen), (int)sizeof (*uh)); 174 #endif 175 free(ptr); 176 return (-1); 177 } 178 179 n = (n > (ntohs(uh->uh_ulen) - sizeof (*uh))) ? 180 ntohs(uh->uh_ulen) - sizeof (*uh) : n; 181 *pkt = ptr; 182 *payload = (void *)((uintptr_t)uh + sizeof (*uh)); 183 return (n); 184 } 185