1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#if 0
36#ifndef lint
37static char sccsid[] = "@(#)net.c	8.4 (Berkeley) 4/28/95";
38#endif
39#endif
40
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD$");
43
44#include <sys/param.h>
45#include <sys/socket.h>
46#include <sys/uio.h>
47#include <wctype.h>
48#include <db.h>
49#include <err.h>
50#include <netdb.h>
51#include <pwd.h>
52#include <stdio.h>
53#include <stdlib.h>
54#include <string.h>
55#include <unistd.h>
56#include <utmpx.h>
57#include <wchar.h>
58#include "finger.h"
59
60static void cleanup(int sig);
61static int do_protocol(const char *name, const struct addrinfo *ai);
62static void trying(const struct addrinfo *ai);
63
64void
65netfinger(char *name)
66{
67	int error, multi;
68	char *host;
69	struct addrinfo *ai, *ai0;
70	static struct addrinfo hint;
71
72	host = strrchr(name, '@');
73	if (host == NULL)
74		return;
75	*host++ = '\0';
76	signal(SIGALRM, cleanup);
77	alarm(TIME_LIMIT);
78
79	hint.ai_flags = AI_CANONNAME;
80	hint.ai_family = family;
81	hint.ai_socktype = SOCK_STREAM;
82
83	error = getaddrinfo(host, "finger", &hint, &ai0);
84	if (error) {
85		warnx("%s: %s", host, gai_strerror(error));
86		return;
87	}
88
89	multi = (ai0->ai_next) != 0;
90
91	/* ai_canonname may not be filled in if the user specified an IP. */
92	if (ai0->ai_canonname == 0)
93		printf("[%s]\n", host);
94	else
95		printf("[%s]\n", ai0->ai_canonname);
96
97	for (ai = ai0; ai != NULL; ai = ai->ai_next) {
98		if (multi)
99			trying(ai);
100
101		error = do_protocol(name, ai);
102		if (!error)
103			break;
104	}
105	alarm(0);
106	freeaddrinfo(ai0);
107}
108
109static int
110do_protocol(const char *name, const struct addrinfo *ai)
111{
112	int cnt, line_len, s;
113	FILE *fp;
114	wint_t c, lastc;
115	struct iovec iov[3];
116	struct msghdr msg;
117	static char slash_w[] = "/W ";
118	static char neteol[] = "\r\n";
119
120	s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
121	if (s < 0) {
122		warn("socket(%d, %d, %d)", ai->ai_family, ai->ai_socktype,
123		     ai->ai_protocol);
124		return -1;
125	}
126
127	msg.msg_name = (void *)ai->ai_addr;
128	msg.msg_namelen = ai->ai_addrlen;
129	msg.msg_iov = iov;
130	msg.msg_iovlen = 0;
131	msg.msg_control = 0;
132	msg.msg_controllen = 0;
133	msg.msg_flags = 0;
134
135	/* -l flag for remote fingerd  */
136	if (lflag) {
137		iov[msg.msg_iovlen].iov_base = slash_w;
138		iov[msg.msg_iovlen++].iov_len = 3;
139	}
140	/* send the name followed by <CR><LF> */
141	iov[msg.msg_iovlen].iov_base = strdup(name);
142	iov[msg.msg_iovlen++].iov_len = strlen(name);
143	iov[msg.msg_iovlen].iov_base = neteol;
144	iov[msg.msg_iovlen++].iov_len = 2;
145
146	if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0) {
147		warn("connect");
148		close(s);
149		return -1;
150	}
151
152	if (sendmsg(s, &msg, 0) < 0) {
153		warn("sendmsg");
154		close(s);
155		return -1;
156	}
157
158	/*
159	 * Read from the remote system; once we're connected, we assume some
160	 * data.  If none arrives, we hang until the user interrupts.
161	 *
162	 * If we see a <CR> or a <CR> with the high bit set, treat it as
163	 * a newline; if followed by a newline character, only output one
164	 * newline.
165	 *
166	 * Otherwise, all high bits are stripped; if it isn't printable and
167	 * it isn't a space, we can simply set the 7th bit.  Every ASCII
168	 * character with bit 7 set is printable.
169	 */
170	lastc = 0;
171	if ((fp = fdopen(s, "r")) != NULL) {
172		cnt = 0;
173		line_len = 0;
174		while ((c = getwc(fp)) != EOF) {
175			if (++cnt > OUTPUT_MAX) {
176				printf("\n\n Output truncated at %d bytes...\n",
177					cnt - 1);
178				break;
179			}
180			if (c == 0x0d) {
181				if (lastc == '\r')	/* ^M^M - skip dupes */
182					continue;
183				c = '\n';
184				lastc = '\r';
185			} else {
186				if (!iswprint(c) && !iswspace(c)) {
187					c &= 0x7f;
188					c |= 0x40;
189				}
190				if (lastc != '\r' || c != '\n')
191					lastc = c;
192				else {
193					lastc = '\n';
194					continue;
195				}
196			}
197			putwchar(c);
198			if (c != '\n' && ++line_len > _POSIX2_LINE_MAX) {
199				putchar('\\');
200				putchar('\n');
201				lastc = '\r';
202			}
203			if (lastc == '\n' || lastc == '\r')
204				line_len = 0;
205		}
206		if (ferror(fp)) {
207			/*
208			 * Assume that whatever it was set errno...
209			 */
210			warn("reading from network");
211		}
212		if (lastc != L'\n')
213			putchar('\n');
214
215		fclose(fp);
216	}
217	return 0;
218}
219
220static void
221trying(const struct addrinfo *ai)
222{
223	char buf[NI_MAXHOST];
224
225	if (getnameinfo(ai->ai_addr, ai->ai_addrlen, buf, sizeof buf,
226			(char *)0, 0, NI_NUMERICHOST) != 0)
227		return;		/* XXX can't happen */
228
229	printf("Trying %s...\n", buf);
230}
231
232static void
233cleanup(int sig __unused)
234{
235#define	ERRSTR	"Timed out.\n"
236	write(STDERR_FILENO, ERRSTR, sizeof ERRSTR);
237	exit(1);
238}
239
240