xref: /netbsd-src/usr.bin/finger/net.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: net.c,v 1.14 2000/07/07 15:13:22 itojun 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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)net.c	8.4 (Berkeley) 4/28/95";
43 #else
44 __RCSID("$NetBSD: net.c,v 1.14 2000/07/07 15:13:22 itojun Exp $");
45 #endif
46 #endif /* not lint */
47 
48 #include <sys/types.h>
49 #include <sys/socket.h>
50 
51 #include <netinet/in.h>
52 
53 #include <arpa/inet.h>
54 
55 #include <netdb.h>
56 #include <db.h>
57 #include <unistd.h>
58 #include <pwd.h>
59 #include <utmp.h>
60 #include <stdio.h>
61 #include <string.h>
62 #include <ctype.h>
63 #include <unistd.h>
64 #include <err.h>
65 
66 #include "finger.h"
67 #include "extern.h"
68 
69 void
70 netfinger(name)
71 	char *name;
72 {
73 	FILE *fp;
74 	int c, lastc;
75 	int s;
76 	char *host;
77 	struct addrinfo hints, *res, *res0;
78 	int error;
79 	char *emsg = NULL;
80 
81 	lastc = 0;
82 	if (!(host = strrchr(name, '@')))
83 		return;
84 	*host++ = '\0';
85 	memset(&hints, 0, sizeof(hints));
86 	hints.ai_family = PF_UNSPEC;
87 	hints.ai_socktype = SOCK_STREAM;
88 	hints.ai_flags = AI_CANONNAME;
89 	error = getaddrinfo(host, "finger", &hints, &res0);
90 	if (error) {
91 		warnx("%s: %s", gai_strerror(error), host);
92 		return;
93 	}
94 
95 	s = -1;
96 	for (res = res0; res; res = res->ai_next) {
97 		s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
98 		if (s < 0) {
99 			emsg = "socket";
100 			continue;
101 		}
102 
103 		if (connect(s, res->ai_addr, res->ai_addrlen)) {
104 			close(s);
105 			s = -1;
106 			emsg = "connect";
107 			continue;
108 		}
109 
110 		break;
111 	}
112 	if (s < 0) {
113 		if (emsg != NULL)
114 			warn("%s", emsg);
115 		return;
116 	}
117 
118 	/* have network connection; identify the host connected with */
119 	(void)printf("[%s]\n", res0->ai_canonname ? res0->ai_canonname : host);
120 
121 	/* -l flag for remote fingerd  */
122 	if (lflag)
123 		write(s, "/W ", 3);
124 	/* send the name followed by <CR><LF> */
125 	(void)write(s, name, strlen(name));
126 	(void)write(s, "\r\n", 2);
127 
128 	/*
129 	 * Read from the remote system; once we're connected, we assume some
130 	 * data.  If none arrives, we hang until the user interrupts.
131 	 *
132 	 * If we see a <CR> or a <CR> with the high bit set, treat it as
133 	 * a newline; if followed by a newline character, only output one
134 	 * newline.
135 	 *
136 	 * Otherwise, all high bits are stripped; if it isn't printable and
137 	 * it isn't a space, we can simply set the 7th bit.  Every ASCII
138 	 * character with bit 7 set is printable.
139 	 */
140 	if ((fp = fdopen(s, "r")) != NULL)
141 		while ((c = getc(fp)) != EOF) {
142 			c &= 0x7f;
143 			if (c == '\r') {
144 				if (lastc == '\r')	/* ^M^M - skip dupes */
145 					continue;
146 				c = '\n';
147 				lastc = '\r';
148 			} else {
149 				if (!isprint(c) && !isspace(c))
150 					c |= 0x40;
151 				if (lastc != '\r' || c != '\n')
152 					lastc = c;
153 				else {
154 					lastc = '\n';
155 					continue;
156 				}
157 			}
158 			putchar(c);
159 		}
160 	if (lastc != '\n')
161 		putchar('\n');
162 	(void)fclose(fp);
163 }
164