xref: /original-bsd/usr.bin/finger/net.c (revision 2622b709)
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  * %sccs.include.redist.c%
9  */
10 
11 #ifndef lint
12 static char sccsid[] = "@(#)net.c	5.5 (Berkeley) 06/01/90";
13 #endif /* not lint */
14 
15 #include <sys/types.h>
16 #include <sys/socket.h>
17 #include <netinet/in.h>
18 #include <netdb.h>
19 #include <stdio.h>
20 #include <ctype.h>
21 
22 netfinger(name)
23 	char *name;
24 {
25 	extern int lflag;
26 	register FILE *fp;
27 	register int c, lastc;
28 	struct in_addr defaddr;
29 	struct hostent *hp, def;
30 	struct servent *sp;
31 	struct sockaddr_in sin;
32 	int s;
33 	char *alist[1], *host, *rindex();
34 	u_long inet_addr();
35 
36 	if (!(host = rindex(name, '@')))
37 		return;
38 	*host++ = NULL;
39 	if (!(hp = gethostbyname(host))) {
40 		defaddr.s_addr = inet_addr(host);
41 		if (defaddr.s_addr == -1) {
42 			(void)fprintf(stderr,
43 			    "finger: unknown host: %s\n", host);
44 			return;
45 		}
46 		def.h_name = host;
47 		def.h_addr_list = alist;
48 		def.h_addr = (char *)&defaddr;
49 		def.h_length = sizeof(struct in_addr);
50 		def.h_addrtype = AF_INET;
51 		def.h_aliases = 0;
52 		hp = &def;
53 	}
54 	if (!(sp = getservbyname("finger", "tcp"))) {
55 		(void)fprintf(stderr, "finger: tcp/finger: unknown service\n");
56 		return;
57 	}
58 	sin.sin_family = hp->h_addrtype;
59 	bcopy(hp->h_addr, (char *)&sin.sin_addr, hp->h_length);
60 	sin.sin_port = sp->s_port;
61 	if ((s = socket(hp->h_addrtype, SOCK_STREAM, 0)) < 0) {
62 		perror("finger: socket");
63 		return;
64 	}
65 
66 	/* have network connection; identify the host connected with */
67 	(void)printf("[%s]\n", hp->h_name);
68 	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
69 		perror("finger: connect");
70 		(void)close(s);
71 		return;
72 	}
73 
74 	/* -l flag for remote fingerd  */
75 	if (lflag)
76 		write(s, "/W ", 3);
77 	/* send the name followed by <CR><LF> */
78 	(void)write(s, name, strlen(name));
79 	(void)write(s, "\r\n", 2);
80 
81 	/*
82 	 * Read from the remote system; once we're connected, we assume some
83 	 * data.  If none arrives, we hang until the user interrupts.
84 	 *
85 	 * If we see a <CR> or a <CR> with the high bit set, treat it as
86 	 * a newline; if followed by a newline character, only output one
87 	 * newline.
88 	 *
89 	 * Otherwise, all high bits are stripped; if it isn't printable and
90 	 * it isn't a space, we can simply set the 7th bit.  Every ASCII
91 	 * character with bit 7 set is printable.
92 	 */
93 	if (fp = fdopen(s, "r"))
94 		while ((c = getc(fp)) != EOF) {
95 			c &= 0x7f;
96 			if (c == 0x0d) {
97 				c = '\n';
98 				lastc = '\r';
99 			} else {
100 				if (!isprint(c) && !isspace(c))
101 					c |= 0x40;
102 				if (lastc != '\r' || c != '\n')
103 					lastc = c;
104 				else {
105 					lastc = '\n';
106 					continue;
107 				}
108 			}
109 			putchar(c);
110 		}
111 	if (lastc != '\n')
112 		putchar('\n');
113 	(void)fclose(fp);
114 }
115