xref: /netbsd-src/usr.bin/finger/net.c (revision da5f4674a3fc214be3572d358b66af40ab9401e7)
1 /*	$NetBSD: net.c,v 1.20 2003/08/07 11:13:45 agc Exp $	*/
2 
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 #include <sys/cdefs.h>
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)net.c	8.4 (Berkeley) 4/28/95";
39 #else
40 __RCSID("$NetBSD: net.c,v 1.20 2003/08/07 11:13:45 agc Exp $");
41 #endif
42 #endif /* not lint */
43 
44 #include <sys/types.h>
45 #include <sys/socket.h>
46 
47 #include <netinet/in.h>
48 
49 #include <arpa/inet.h>
50 
51 #include <netdb.h>
52 #include <time.h>
53 #include <db.h>
54 #include <unistd.h>
55 #include <pwd.h>
56 #include <stdio.h>
57 #include <string.h>
58 #include <ctype.h>
59 #include <unistd.h>
60 #include <err.h>
61 
62 #include "utmpentry.h"
63 
64 #include "finger.h"
65 #include "extern.h"
66 
67 void
68 netfinger(name)
69 	char *name;
70 {
71 	FILE *fp;
72 	int c, lastc;
73 	int s;
74 	char *host;
75 	struct addrinfo hints, *res, *res0;
76 	int error;
77 	char *emsg = NULL;
78 
79 	lastc = 0;
80 	if (!(host = strrchr(name, '@')))
81 		return;
82 	*host++ = '\0';
83 	memset(&hints, 0, sizeof(hints));
84 	hints.ai_family = PF_UNSPEC;
85 	hints.ai_socktype = SOCK_STREAM;
86 	hints.ai_flags = AI_CANONNAME;
87 	error = getaddrinfo(host, "finger", &hints, &res0);
88 	if (error) {
89 		warnx("%s: %s", gai_strerror(error), host);
90 		return;
91 	}
92 
93 	s = -1;
94 	for (res = res0; res; res = res->ai_next) {
95 		s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
96 		if (s < 0) {
97 			emsg = "socket";
98 			continue;
99 		}
100 
101 		if (connect(s, res->ai_addr, res->ai_addrlen)) {
102 			close(s);
103 			s = -1;
104 			emsg = "connect";
105 			continue;
106 		}
107 
108 		break;
109 	}
110 	if (s < 0) {
111 		if (emsg != NULL)
112 			warn("%s", emsg);
113 		return;
114 	}
115 
116 	/* have network connection; identify the host connected with */
117 	(void)printf("[%s]\n", res0->ai_canonname ? res0->ai_canonname : host);
118 
119 	/* -l flag for remote fingerd  */
120 	if (lflag)
121 		write(s, "/W ", 3);
122 	/* send the name followed by <CR><LF> */
123 	(void)write(s, name, strlen(name));
124 	(void)write(s, "\r\n", 2);
125 
126 	/*
127 	 * Read from the remote system; once we're connected, we assume some
128 	 * data.  If none arrives, we hang until the user interrupts.
129 	 *
130 	 * If we see a <CR> followed by a newline character, only output
131 	 * one newline.
132 	 *
133 	 * If a character isn't printable and it isn't a space, we strip the
134 	 * 8th bit and set the 7th bit.  Every ASCII character with bit 7 set
135 	 * is printable.
136 	 */
137 	if ((fp = fdopen(s, "r")) != NULL)
138 		while ((c = getc(fp)) != EOF) {
139 			if (c == '\r') {
140 				if (lastc == '\r')	/* ^M^M - skip dupes */
141 					continue;
142 				c = '\n';
143 				lastc = '\r';
144 			} else {
145 				if (!(eightflag || isprint(c) || isspace(c))) {
146 					c &= 0x7f;
147 					c |= 0x40;
148 				}
149 				if (lastc != '\r' || c != '\n')
150 					lastc = c;
151 				else {
152 					lastc = '\n';
153 					continue;
154 				}
155 			}
156 			putchar(c);
157 		}
158 	if (lastc != '\n')
159 		putchar('\n');
160 	(void)fclose(fp);
161 }
162