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!! */
66 ssize_t
sendudp(struct iodesc * d,void * pkt,size_t len)67 sendudp(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 */
105 ssize_t
readudp(struct iodesc * d,void * pkt,size_t len,saseconds_t tleft)106 readudp(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