xref: /netbsd-src/usr.bin/finger/net.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*
2  * Copyright (c) 1989 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 /*static char sccsid[] = "from: @(#)net.c	5.5 (Berkeley) 6/1/90";*/
39 static char rcsid[] = "$Id: net.c,v 1.6 1995/05/21 15:06:52 mycroft Exp $";
40 #endif /* not lint */
41 
42 #include <sys/types.h>
43 #include <sys/socket.h>
44 #include <netinet/in.h>
45 #include <arpa/inet.h>
46 #include <netdb.h>
47 #include <stdio.h>
48 #include <string.h>
49 #include <ctype.h>
50 
51 netfinger(name)
52 	char *name;
53 {
54 	extern int lflag;
55 	register FILE *fp;
56 	register int c, lastc;
57 	struct hostent *hp, def;
58 	struct servent *sp;
59 	struct sockaddr_in sin;
60 	int s;
61 	char *alist[1], *host, *rindex();
62 
63 	if (!(host = rindex(name, '@')))
64 		return;
65 	*host++ = NULL;
66 	if (inet_aton(host, &sin.sin_addr) == 0) {
67 		hp = gethostbyname(host);
68 		if (hp == 0) {
69 			(void)fprintf(stderr,
70 			    "finger: unknown host: %s\n", host);
71 			return;
72 		}
73 		sin.sin_family = hp->h_addrtype;
74 		bcopy(hp->h_addr, (char *)&sin.sin_addr, hp->h_length);
75 		host = hp->h_name;
76 	} else
77 		sin.sin_family = AF_INET;
78 	if (!(sp = getservbyname("finger", "tcp"))) {
79 		(void)fprintf(stderr, "finger: tcp/finger: unknown service\n");
80 		return;
81 	}
82 	sin.sin_port = sp->s_port;
83 	if ((s = socket(sin.sin_family, SOCK_STREAM, 0)) < 0) {
84 		perror("finger: socket");
85 		return;
86 	}
87 
88 	/* have network connection; identify the host connected with */
89 	(void)printf("[%s]\n", host);
90 	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
91 		perror("finger: connect");
92 		(void)close(s);
93 		return;
94 	}
95 
96 	/* -l flag for remote fingerd  */
97 	if (lflag)
98 		write(s, "/W ", 3);
99 	/* send the name followed by <CR><LF> */
100 	(void)write(s, name, strlen(name));
101 	(void)write(s, "\r\n", 2);
102 
103 	/*
104 	 * Read from the remote system; once we're connected, we assume some
105 	 * data.  If none arrives, we hang until the user interrupts.
106 	 *
107 	 * If we see a <CR> or a <CR> with the high bit set, treat it as
108 	 * a newline; if followed by a newline character, only output one
109 	 * newline.
110 	 *
111 	 * Otherwise, all high bits are stripped; if it isn't printable and
112 	 * it isn't a space, we can simply set the 7th bit.  Every ASCII
113 	 * character with bit 7 set is printable.
114 	 */
115 	if (fp = fdopen(s, "r"))
116 		while ((c = getc(fp)) != EOF) {
117 			c &= 0x7f;
118 			if (c == '\r') {
119 				if (lastc == '\r')
120 					continue;
121 				c = '\n';
122 				lastc = '\r';
123 			} else {
124 				if (!isprint(c) && !isspace(c))
125 					c |= 0x40;
126 				if (lastc != '\r' || c != '\n')
127 					lastc = c;
128 				else {
129 					lastc = '\n';
130 					continue;
131 				}
132 			}
133 			putchar(c);
134 		}
135 	if (lastc != '\n')
136 		putchar('\n');
137 	(void)fclose(fp);
138 }
139