xref: /freebsd/libexec/tftpd/tftp-utils.c (revision e63d20b70ee1dbee9b075f29de6f30cdcfe1abe1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 
33 #include <netinet/in.h>
34 #include <arpa/tftp.h>
35 
36 #include <errno.h>
37 #include <stdarg.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <syslog.h>
42 
43 #include "tftp-utils.h"
44 #include "tftp-io.h"
45 
46 /*
47  * Default values, can be changed later via the TFTP Options
48  */
49 int		timeoutpacket = TIMEOUT;
50 int		timeoutnetwork = MAX_TIMEOUTS * TIMEOUT;
51 int		maxtimeouts = MAX_TIMEOUTS;
52 uint16_t	segsize = SEGSIZE;
53 uint16_t	pktsize = SEGSIZE + 4;
54 uint16_t	windowsize = WINDOWSIZE;
55 
56 int	acting_as_client;
57 
58 
59 /*
60  * Set timeout values for packet reception. The idea is that you
61  * get 'maxtimeouts' of 5 seconds between 'timeoutpacket' (i.e. the
62  * first timeout) to 'timeoutnetwork' (i.e. the last timeout)
63  */
64 int
65 settimeouts(int _timeoutpacket, int _timeoutnetwork, int _maxtimeouts __unused)
66 {
67 	int i;
68 
69 	/* We cannot do impossible things */
70 	if (_timeoutpacket >= _timeoutnetwork)
71 		return (0);
72 
73 	maxtimeouts = 0;
74 	i = _timeoutpacket;
75 	while (i < _timeoutnetwork || maxtimeouts < MIN_TIMEOUTS) {
76 		maxtimeouts++;
77 		i += 5;
78 	}
79 
80 	timeoutpacket = _timeoutpacket;
81 	timeoutnetwork = i;
82 	return (1);
83 }
84 
85 /* translate IPv4 mapped IPv6 address to IPv4 address */
86 void
87 unmappedaddr(struct sockaddr_in6 *sin6)
88 {
89 	struct sockaddr_in *sin4;
90 	u_int32_t addr;
91 	int port;
92 
93 	if (sin6->sin6_family != AF_INET6 ||
94 	    !IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
95 		return;
96 	sin4 = (struct sockaddr_in *)sin6;
97 	memcpy(&addr, &sin6->sin6_addr.s6_addr[12], sizeof(addr));
98 	port = sin6->sin6_port;
99 	memset(sin4, 0, sizeof(struct sockaddr_in));
100 	sin4->sin_addr.s_addr = addr;
101 	sin4->sin_port = port;
102 	sin4->sin_family = AF_INET;
103 	sin4->sin_len = sizeof(struct sockaddr_in);
104 }
105 
106 /* Get a field from a \0 separated string */
107 size_t
108 get_field(int peer, char *buffer, size_t size)
109 {
110 	char *cp = buffer;
111 
112 	while (cp < buffer + size) {
113 		if (*cp == '\0') break;
114 		cp++;
115 	}
116 	if (*cp != '\0') {
117 		tftp_log(LOG_ERR, "Bad option - no trailing \\0 found");
118 		send_error(peer, EBADOP);
119 		exit(1);
120 	}
121 	return (cp - buffer + 1);
122 }
123 
124 /*
125  * Logging functions
126  */
127 static int _tftp_logtostdout = 1;
128 
129 void
130 tftp_openlog(const char *ident, int logopt, int facility)
131 {
132 
133 	_tftp_logtostdout = (ident == NULL);
134 	if (_tftp_logtostdout == 0)
135 		openlog(ident, logopt, facility);
136 }
137 
138 void
139 tftp_closelog(void)
140 {
141 
142 	if (_tftp_logtostdout == 0)
143 		closelog();
144 }
145 
146 void
147 tftp_log(int priority, const char *message, ...)
148 {
149 	va_list ap;
150 	int serrno;
151 	char *s;
152 
153 	serrno = errno;
154 	va_start(ap, message);
155 	if (_tftp_logtostdout == 0) {
156 		vasprintf(&s, message, ap);
157 		syslog(priority, "%s", s);
158 	} else {
159 		vprintf(message, ap);
160 		printf("\n");
161 	}
162 	va_end(ap);
163 	errno = serrno;
164 }
165 
166 /*
167  * Packet types
168  */
169 struct packettypes packettypes[] = {
170 	{ RRQ,		"RRQ"	},
171 	{ WRQ,		"WRQ"	},
172 	{ DATA,		"DATA"	},
173 	{ ACK,		"ACK"	},
174 	{ ERROR,	"ERROR"	},
175 	{ OACK,		"OACK"	},
176 	{ 0,		NULL	},
177 };
178 
179 const char *
180 packettype(int type)
181 {
182 	static char failed[100];
183 	int i = 0;
184 
185 	while (packettypes[i].name != NULL) {
186 		if (packettypes[i].value == type)
187 			break;
188 		i++;
189 	}
190 	if (packettypes[i].name != NULL)
191 		return packettypes[i].name;
192 	sprintf(failed, "unknown (type: %d)", type);
193 	return (failed);
194 }
195 
196 /*
197  * Debugs
198  */
199 int	debug = DEBUG_NONE;
200 struct debugs debugs[] = {
201 	{ DEBUG_PACKETS,	"packet",	"Packet debugging"	},
202 	{ DEBUG_SIMPLE,		"simple",	"Simple debugging"	},
203 	{ DEBUG_OPTIONS,	"options",	"Options debugging"	},
204 	{ DEBUG_ACCESS,		"access",	"TCPd access debugging"	},
205 	{ DEBUG_NONE,		NULL,		"No debugging"		},
206 };
207 unsigned int packetdroppercentage = 0;
208 
209 int
210 debug_find(char *s)
211 {
212 	int i = 0;
213 
214 	while (debugs[i].name != NULL) {
215 		if (strcasecmp(debugs[i].name, s) == 0)
216 			break;
217 		i++;
218 	}
219 	return (debugs[i].value);
220 }
221 
222 int
223 debug_finds(char *s)
224 {
225 	int i = 0;
226 	char *ps = s;
227 
228 	while (s != NULL) {
229 		ps = strchr(s, ' ');
230 		if (ps != NULL)
231 			*ps = '\0';
232 		i += debug_find(s);
233 		if (ps != NULL)
234 			*ps = ' ';
235 		s = ps;
236 	}
237 	return (i);
238 }
239 
240 const char *
241 debug_show(int d)
242 {
243 	static char s[100];
244 	size_t space = sizeof(s);
245 	int i = 0;
246 
247 	s[0] = '\0';
248 	while (debugs[i].name != NULL) {
249 		if (d&debugs[i].value) {
250 			if (s[0] != '\0')
251 				strlcat(s, " ", space);
252 			strlcat(s, debugs[i].name, space);
253 		}
254 		i++;
255 	}
256 	if (s[0] != '\0')
257 		return (s);
258 	return ("none");
259 }
260 
261 /*
262  * RP_
263  */
264 struct rp_errors rp_errors[] = {
265 	{ RP_TIMEOUT,		"Network timeout" },
266 	{ RP_TOOSMALL,		"Not enough data bytes" },
267 	{ RP_WRONGSOURCE,	"Invalid IP address of UDP port" },
268 	{ RP_ERROR,		"Error packet" },
269 	{ RP_RECVFROM,		"recvfrom() complained" },
270 	{ RP_TOOBIG,		"Too many data bytes" },
271 	{ RP_NONE,		NULL }
272 };
273 
274 char *
275 rp_strerror(int error)
276 {
277 	static char s[100];
278 	size_t space = sizeof(s);
279 	int i = 0;
280 
281 	while (rp_errors[i].desc != NULL) {
282 		if (rp_errors[i].error == error) {
283 			strlcpy(s, rp_errors[i].desc, space);
284 			space -= strlen(rp_errors[i].desc);
285 		}
286 		i++;
287 	}
288 	if (s[0] == '\0')
289 		sprintf(s, "unknown (error=%d)", error);
290 	return (s);
291 }
292 
293 /*
294  * Performance figures
295  */
296 
297 void
298 stats_init(struct tftp_stats *ts)
299 {
300 
301 	ts->amount = 0;
302 	ts->rollovers = 0;
303 	ts->retries = 0;
304 	ts->blocks = 0;
305 	ts->amount = 0;
306 	gettimeofday(&(ts->tstart), NULL);
307 }
308 
309 void
310 printstats(const char *direction, int verbose, struct tftp_stats *ts)
311 {
312 	double delta;	/* compute delta in 1/10's second units */
313 
314 	delta = ((ts->tstop.tv_sec*10.)+(ts->tstop.tv_usec/100000)) -
315 		((ts->tstart.tv_sec*10.)+(ts->tstart.tv_usec/100000));
316 	delta = delta/10.;      /* back to seconds */
317 
318 	printf("%s %zu bytes during %.1f seconds in %u blocks",
319 	    direction, ts->amount, delta, ts->blocks);
320 
321 	if (ts->rollovers != 0)
322 		printf(" with %d rollover%s",
323 		    ts->rollovers, ts->rollovers != 1 ? "s" : "");
324 
325 	if (verbose)
326 		printf(" [%.0f bits/sec]", (ts->amount*8.)/delta);
327 	putchar('\n');
328 }
329