1/* $NetBSD: udp.c,v 1.13 2019/03/31 20:08:45 christos 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. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Lawrence Berkeley Laboratory and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL) 40 */ 41 42#include <sys/param.h> 43#include <sys/socket.h> 44 45#ifdef _STANDALONE 46#include <lib/libkern/libkern.h> 47#else 48#include <string.h> 49#endif 50 51#include <net/if.h> 52#include <net/if_ether.h> 53 54#include <netinet/in.h> 55#include <netinet/in_systm.h> 56#include <netinet/ip.h> 57#include <netinet/ip_var.h> 58#include <netinet/udp.h> 59#include <netinet/udp_var.h> 60 61#include "stand.h" 62#include "net.h" 63 64 65/* Caller must leave room for ethernet, ip and udp headers in front!! */ 66ssize_t 67sendudp(struct iodesc *d, void *pkt, size_t len) 68{ 69 ssize_t cc; 70 struct udphdr *uh; 71 72#ifdef NET_DEBUG 73 if (debug) { 74 printf("%s: d=%p called.\n", __func__, d); 75 if (d) { 76 printf("saddr: %s:%d", 77 inet_ntoa(d->myip), ntohs(d->myport)); 78 printf(" daddr: %s:%d\n", 79 inet_ntoa(d->destip), ntohs(d->destport)); 80 } 81 } 82#endif 83 84 uh = (struct udphdr *)pkt - 1; 85 len += sizeof(*uh); 86 87 (void)memset(uh, 0, sizeof(*uh)); 88 89 uh->uh_sport = d->myport; 90 uh->uh_dport = d->destport; 91 uh->uh_ulen = htons(len); 92 93 cc = sendip(d, uh, len, IPPROTO_UDP); 94 if (cc == -1) 95 return -1; 96 if ((size_t)cc != len) 97 panic("%s: bad write (%zd != %zu)", __func__, cc, len); 98 return (cc - sizeof(*uh)); 99} 100 101/* 102 * Receive a UDP packet and validate it is for us. 103 * Caller leaves room for the headers (Ether, IP, UDP) 104 */ 105ssize_t 106readudp(struct iodesc *d, void *pkt, size_t len, saseconds_t tleft) 107{ 108 ssize_t n; 109 struct udphdr *uh; 110 111 uh = (struct udphdr *)pkt - 1; 112 n = readip(d, uh, len + sizeof(*uh), tleft, IPPROTO_UDP); 113 if (n == -1 || (size_t)n < sizeof(*uh)) 114 return -1; 115 116 if (uh->uh_dport != d->myport) { 117#ifdef NET_DEBUG 118 if (debug) 119 printf("%s: bad dport %d != %d\n", __func__, 120 ntohs(d->myport), ntohs(uh->uh_dport)); 121#endif 122 return -1; 123 } 124 125 if (ntohs(uh->uh_ulen) < sizeof(*uh)) { 126#ifdef NET_DEBUG 127 if (debug) 128 printf("%s: bad udp len %d < %zu\n", __func__, 129 ntohs(uh->uh_ulen), sizeof(*uh)); 130#endif 131 return -1; 132 } 133 134 n -= sizeof(*uh); 135 return n; 136} 137