net.c revision 331251 
1/*	$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 * 4. 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__FBSDID("$FreeBSD: stable/11/stand/libsa/net.c 331251 2018-03-20 17:41:54Z kevans $");
40
41#include <sys/param.h>
42#include <sys/socket.h>
43
44#include <string.h>
45
46#include <net/if.h>
47#include <netinet/in.h>
48#include <netinet/if_ether.h>
49#include <netinet/in_systm.h>
50
51#include <netinet/in_pcb.h>
52#include <netinet/ip.h>
53#include <netinet/ip_var.h>
54#include <netinet/udp.h>
55#include <netinet/udp_var.h>
56
57#include "stand.h"
58#include "net.h"
59
60/*
61 * Send a packet and wait for a reply, with exponential backoff.
62 *
63 * The send routine must return the actual number of bytes written,
64 * or -1 on error.
65 *
66 * The receive routine can indicate success by returning the number of
67 * bytes read; it can return 0 to indicate EOF; it can return -1 with a
68 * non-zero errno to indicate failure; finally, it can return -1 with a
69 * zero errno to indicate it isn't done yet.
70 */
71ssize_t
72sendrecv(struct iodesc *d,
73    ssize_t (*sproc)(struct iodesc *, void *, size_t),
74    void *sbuf, size_t ssize,
75    ssize_t (*rproc)(struct iodesc *, void **, void **, time_t, void *),
76    void **pkt, void **payload, void *recv_extra)
77{
78	ssize_t cc;
79	time_t t, tmo, tlast;
80	time_t tref;
81	long tleft;
82
83#ifdef NET_DEBUG
84	if (debug)
85		printf("sendrecv: called\n");
86#endif
87
88	tmo = MINTMO;
89	tlast = 0;
90	tleft = 0;
91	tref = getsecs();
92	t = getsecs();
93	for (;;) {
94		if (MAXWAIT > 0 && (getsecs() - tref) >= MAXWAIT) {
95			errno = ETIMEDOUT;
96			return -1;
97		}
98		if (tleft <= 0) {
99			if (tmo >= MAXTMO) {
100				errno = ETIMEDOUT;
101				return -1;
102			}
103			cc = (*sproc)(d, sbuf, ssize);
104			if (cc != -1 && cc < ssize)
105				panic("sendrecv: short write! (%zd < %zd)",
106				    cc, ssize);
107
108			tleft = tmo;
109			tmo += MINTMO;
110			if (tmo > MAXTMO)
111				tmo = MAXTMO;
112
113			if (cc == -1) {
114				/* Error on transmit; wait before retrying */
115				while ((getsecs() - t) < tmo)
116					;
117				tleft = 0;
118				continue;
119			}
120
121			tlast = t;
122		}
123
124		/* Try to get a packet and process it. */
125		cc = (*rproc)(d, pkt, payload, tleft, recv_extra);
126		/* Return on data, EOF or real error. */
127		if (cc != -1 || (errno != 0 && errno != ETIMEDOUT))
128			return (cc);
129
130		/* Timed out or didn't get the packet we're waiting for */
131		t = getsecs();
132		tleft -= t - tlast;
133		tlast = t;
134	}
135}
136
137/*
138 * Like inet_addr() in the C library, but we only accept base-10.
139 * Return values are in network order.
140 */
141n_long
142inet_addr(char *cp)
143{
144	u_long val;
145	int n;
146	char c;
147	u_int parts[4];
148	u_int *pp = parts;
149
150	for (;;) {
151		/*
152		 * Collect number up to ``.''.
153		 * Values are specified as for C:
154		 * 0x=hex, 0=octal, other=decimal.
155		 */
156		val = 0;
157		while ((c = *cp) != '\0') {
158			if (c >= '0' && c <= '9') {
159				val = (val * 10) + (c - '0');
160				cp++;
161				continue;
162			}
163			break;
164		}
165		if (*cp == '.') {
166			/*
167			 * Internet format:
168			 *	a.b.c.d
169			 *	a.b.c	(with c treated as 16-bits)
170			 *	a.b	(with b treated as 24 bits)
171			 */
172			if (pp >= parts + 3 || val > 0xff)
173				goto bad;
174			*pp++ = val, cp++;
175		} else
176			break;
177	}
178	/*
179	 * Check for trailing characters.
180	 */
181	if (*cp != '\0')
182		goto bad;
183
184	/*
185	 * Concoct the address according to
186	 * the number of parts specified.
187	 */
188	n = pp - parts + 1;
189	switch (n) {
190
191	case 1:				/* a -- 32 bits */
192		break;
193
194	case 2:				/* a.b -- 8.24 bits */
195		if (val > 0xffffff)
196			goto bad;
197		val |= parts[0] << 24;
198		break;
199
200	case 3:				/* a.b.c -- 8.8.16 bits */
201		if (val > 0xffff)
202			goto bad;
203		val |= (parts[0] << 24) | (parts[1] << 16);
204		break;
205
206	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
207		if (val > 0xff)
208			goto bad;
209		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
210		break;
211	}
212
213	return (htonl(val));
214 bad:
215	return (htonl(INADDR_NONE));
216}
217
218char *
219inet_ntoa(struct in_addr ia)
220{
221	return (intoa(ia.s_addr));
222}
223
224/* Similar to inet_ntoa() */
225char *
226intoa(n_long addr)
227{
228	char *cp;
229	u_int byte;
230	int n;
231	static char buf[17];	/* strlen(".255.255.255.255") + 1 */
232
233	addr = ntohl(addr);
234	cp = &buf[sizeof buf];
235	*--cp = '\0';
236
237	n = 4;
238	do {
239		byte = addr & 0xff;
240		*--cp = byte % 10 + '0';
241		byte /= 10;
242		if (byte > 0) {
243			*--cp = byte % 10 + '0';
244			byte /= 10;
245			if (byte > 0)
246				*--cp = byte + '0';
247		}
248		*--cp = '.';
249		addr >>= 8;
250	} while (--n > 0);
251
252	return (cp+1);
253}
254
255static char *
256number(char *s, int *n)
257{
258	for (*n = 0; isdigit(*s); s++)
259		*n = (*n * 10) + *s - '0';
260	return s;
261}
262
263n_long
264ip_convertaddr(char *p)
265{
266#define IP_ANYADDR	0
267	n_long addr = 0, n;
268
269	if (p == (char *)0 || *p == '\0')
270		return IP_ANYADDR;
271	p = number(p, &n);
272	addr |= (n << 24) & 0xff000000;
273	if (*p == '\0' || *p++ != '.')
274		return IP_ANYADDR;
275	p = number(p, &n);
276	addr |= (n << 16) & 0xff0000;
277	if (*p == '\0' || *p++ != '.')
278		return IP_ANYADDR;
279	p = number(p, &n);
280	addr |= (n << 8) & 0xff00;
281	if (*p == '\0' || *p++ != '.')
282		return IP_ANYADDR;
283	p = number(p, &n);
284	addr |= n & 0xff;
285	if (*p != '\0')
286		return IP_ANYADDR;
287
288	return htonl(addr);
289}
290