xref: /freebsd/libexec/tftpd/tftp-utils.c (revision eb0292d92974781023999df7f654dbcf1c057960)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (C) 2008 Edwin Groothuis. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/socket.h>
32 #include <sys/stat.h>
33 #include <sys/time.h>
34 
35 #include <netinet/in.h>
36 #include <arpa/tftp.h>
37 
38 #include <stdarg.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <syslog.h>
43 
44 #include "tftp-utils.h"
45 #include "tftp-io.h"
46 
47 /*
48  * Default values, can be changed later via the TFTP Options
49  */
50 int		timeoutpacket = TIMEOUT;
51 int		timeoutnetwork = MAX_TIMEOUTS * TIMEOUT;
52 int		maxtimeouts = MAX_TIMEOUTS;
53 uint16_t	segsize = SEGSIZE;
54 uint16_t	pktsize = SEGSIZE + 4;
55 uint16_t	windowsize = WINDOWSIZE;
56 
57 int	acting_as_client;
58 
59 
60 /*
61  * Set timeout values for packet reception. The idea is that you
62  * get 'maxtimeouts' of 5 seconds between 'timeoutpacket' (i.e. the
63  * first timeout) to 'timeoutnetwork' (i.e. the last timeout)
64  */
65 int
66 settimeouts(int _timeoutpacket, int _timeoutnetwork, int _maxtimeouts __unused)
67 {
68 	int i;
69 
70 	/* We cannot do impossible things */
71 	if (_timeoutpacket >= _timeoutnetwork)
72 		return (0);
73 
74 	maxtimeouts = 0;
75 	i = _timeoutpacket;
76 	while (i < _timeoutnetwork || maxtimeouts < MIN_TIMEOUTS) {
77 		maxtimeouts++;
78 		i += 5;
79 	}
80 
81 	timeoutpacket = _timeoutpacket;
82 	timeoutnetwork = i;
83 	return (1);
84 }
85 
86 /* translate IPv4 mapped IPv6 address to IPv4 address */
87 void
88 unmappedaddr(struct sockaddr_in6 *sin6)
89 {
90 	struct sockaddr_in *sin4;
91 	u_int32_t addr;
92 	int port;
93 
94 	if (sin6->sin6_family != AF_INET6 ||
95 	    !IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
96 		return;
97 	sin4 = (struct sockaddr_in *)sin6;
98 	memcpy(&addr, &sin6->sin6_addr.s6_addr[12], sizeof(addr));
99 	port = sin6->sin6_port;
100 	memset(sin4, 0, sizeof(struct sockaddr_in));
101 	sin4->sin_addr.s_addr = addr;
102 	sin4->sin_port = port;
103 	sin4->sin_family = AF_INET;
104 	sin4->sin_len = sizeof(struct sockaddr_in);
105 }
106 
107 /* Get a field from a \0 separated string */
108 ssize_t
109 get_field(int peer, char *buffer, ssize_t size)
110 {
111 	char *cp = buffer;
112 
113 	while (cp < buffer + size) {
114 		if (*cp == '\0') break;
115 		cp++;
116 	}
117 	if (*cp != '\0') {
118 		tftp_log(LOG_ERR, "Bad option - no trailing \\0 found");
119 		send_error(peer, EBADOP);
120 		exit(1);
121 	}
122 	return (cp - buffer + 1);
123 }
124 
125 /*
126  * Logging functions
127  */
128 static int _tftp_logtostdout = 1;
129 
130 void
131 tftp_openlog(const char *ident, int logopt, int facility)
132 {
133 
134 	_tftp_logtostdout = (ident == NULL);
135 	if (_tftp_logtostdout == 0)
136 		openlog(ident, logopt, facility);
137 }
138 
139 void
140 tftp_closelog(void)
141 {
142 
143 	if (_tftp_logtostdout == 0)
144 		closelog();
145 }
146 
147 void
148 tftp_log(int priority, const char *message, ...)
149 {
150 	va_list ap;
151 	char *s;
152 
153 	va_start(ap, message);
154 	if (_tftp_logtostdout == 0) {
155 		vasprintf(&s, message, ap);
156 		syslog(priority, "%s", s);
157 	} else {
158 		vprintf(message, ap);
159 		printf("\n");
160 	}
161 	va_end(ap);
162 }
163 
164 /*
165  * Packet types
166  */
167 struct packettypes packettypes[] = {
168 	{ RRQ,		"RRQ"	},
169 	{ WRQ,		"WRQ"	},
170 	{ DATA,		"DATA"	},
171 	{ ACK,		"ACK"	},
172 	{ ERROR,	"ERROR"	},
173 	{ OACK,		"OACK"	},
174 	{ 0,		NULL	},
175 };
176 
177 const char *
178 packettype(int type)
179 {
180 	static char failed[100];
181 	int i = 0;
182 
183 	while (packettypes[i].name != NULL) {
184 		if (packettypes[i].value == type)
185 			break;
186 		i++;
187 	}
188 	if (packettypes[i].name != NULL)
189 		return packettypes[i].name;
190 	sprintf(failed, "unknown (type: %d)", type);
191 	return (failed);
192 }
193 
194 /*
195  * Debugs
196  */
197 int	debug = DEBUG_NONE;
198 struct debugs debugs[] = {
199 	{ DEBUG_PACKETS,	"packet",	"Packet debugging"	},
200 	{ DEBUG_SIMPLE,		"simple",	"Simple debugging"	},
201 	{ DEBUG_OPTIONS,	"options",	"Options debugging"	},
202 	{ DEBUG_ACCESS,		"access",	"TCPd access debugging"	},
203 	{ DEBUG_NONE,		NULL,		"No debugging"		},
204 };
205 int	packetdroppercentage = 0;
206 
207 int
208 debug_find(char *s)
209 {
210 	int i = 0;
211 
212 	while (debugs[i].name != NULL) {
213 		if (strcasecmp(debugs[i].name, s) == 0)
214 			break;
215 		i++;
216 	}
217 	return (debugs[i].value);
218 }
219 
220 int
221 debug_finds(char *s)
222 {
223 	int i = 0;
224 	char *ps = s;
225 
226 	while (s != NULL) {
227 		ps = strchr(s, ' ');
228 		if (ps != NULL)
229 			*ps = '\0';
230 		i += debug_find(s);
231 		if (ps != NULL)
232 			*ps = ' ';
233 		s = ps;
234 	}
235 	return (i);
236 }
237 
238 const char *
239 debug_show(int d)
240 {
241 	static char s[100];
242 	size_t space = sizeof(s);
243 	int i = 0;
244 
245 	s[0] = '\0';
246 	while (debugs[i].name != NULL) {
247 		if (d&debugs[i].value) {
248 			if (s[0] != '\0')
249 				strlcat(s, " ", space);
250 			strlcat(s, debugs[i].name, space);
251 		}
252 		i++;
253 	}
254 	if (s[0] != '\0')
255 		return (s);
256 	return ("none");
257 }
258 
259 /*
260  * RP_
261  */
262 struct rp_errors rp_errors[] = {
263 	{ RP_TIMEOUT,		"Network timeout" },
264 	{ RP_TOOSMALL,		"Not enough data bytes" },
265 	{ RP_WRONGSOURCE,	"Invalid IP address of UDP port" },
266 	{ RP_ERROR,		"Error packet" },
267 	{ RP_RECVFROM,		"recvfrom() complained" },
268 	{ RP_TOOBIG,		"Too many data bytes" },
269 	{ RP_NONE,		NULL }
270 };
271 
272 char *
273 rp_strerror(int error)
274 {
275 	static char s[100];
276 	size_t space = sizeof(s);
277 	int i = 0;
278 
279 	while (rp_errors[i].desc != NULL) {
280 		if (rp_errors[i].error == error) {
281 			strlcpy(s, rp_errors[i].desc, space);
282 			space -= strlen(rp_errors[i].desc);
283 		}
284 		i++;
285 	}
286 	if (s[0] == '\0')
287 		sprintf(s, "unknown (error=%d)", error);
288 	return (s);
289 }
290 
291 /*
292  * Performance figures
293  */
294 
295 void
296 stats_init(struct tftp_stats *ts)
297 {
298 
299 	ts->amount = 0;
300 	ts->rollovers = 0;
301 	ts->retries = 0;
302 	ts->blocks = 0;
303 	ts->amount = 0;
304 	gettimeofday(&(ts->tstart), NULL);
305 }
306 
307 void
308 printstats(const char *direction, int verbose, struct tftp_stats *ts)
309 {
310 	double delta;	/* compute delta in 1/10's second units */
311 
312 	delta = ((ts->tstop.tv_sec*10.)+(ts->tstop.tv_usec/100000)) -
313 		((ts->tstart.tv_sec*10.)+(ts->tstart.tv_usec/100000));
314 	delta = delta/10.;      /* back to seconds */
315 
316 	printf("%s %zu bytes during %.1f seconds in %u blocks",
317 	    direction, ts->amount, delta, ts->blocks);
318 
319 	if (ts->rollovers != 0)
320 		printf(" with %d rollover%s",
321 		    ts->rollovers, ts->rollovers != 1 ? "s" : "");
322 
323 	if (verbose)
324 		printf(" [%.0f bits/sec]", (ts->amount*8.)/delta);
325 	putchar('\n');
326 }
327