1/*	$OpenBSD: net.c,v 1.15 2023/02/08 08:24:29 tb Exp $	*/
2
3/*
4 * Copyright (c) 1989 The Regents of the University of California.
5 * 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/socket.h>
36#include <netinet/in.h>
37#include <arpa/inet.h>
38#include <netdb.h>
39#include <stdio.h>
40#include <string.h>
41#include <ctype.h>
42#include <unistd.h>
43#include <err.h>
44#include "finger.h"
45#include "extern.h"
46
47void
48netfinger(char *name)
49{
50	FILE *fp;
51	int c, lastc;
52	int s;
53	char *host;
54	struct addrinfo hints, *res0, *res;
55	int error;
56	char hbuf[NI_MAXHOST];
57
58	lastc = 0;
59	if (!(host = strrchr(name, '@')))
60		return;
61	*host++ = '\0';
62	memset(&hints, 0, sizeof(hints));
63	hints.ai_family = PF_UNSPEC;
64	hints.ai_socktype = SOCK_STREAM;
65	error = getaddrinfo(host, "finger", &hints, &res0);
66	if (error) {
67		warnx("%s", gai_strerror(error));
68		return;
69	}
70
71	s = -1;
72	for (res = res0; res; res = res->ai_next) {
73		if ((s = socket(res->ai_family, res->ai_socktype,
74				res->ai_protocol)) == -1) {
75			continue;
76		}
77		if (connect(s, res->ai_addr, res->ai_addrlen) == -1) {
78			(void)close(s);
79			s = -1;
80			continue;
81		}
82
83		break;
84	}
85
86	if (s == -1) {
87		perror("finger");
88		freeaddrinfo(res0);
89		return;
90	}
91
92	/* have network connection; identify the host connected with */
93	if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf, sizeof(hbuf),
94	    NULL, 0, NI_NUMERICHOST) != 0) {
95		strlcpy(hbuf, "(invalid)", sizeof hbuf);
96	}
97	(void)printf("[%s/%s]\n", host, hbuf);
98
99	freeaddrinfo(res0);
100
101	/* -l flag for remote fingerd  */
102	if (lflag)
103		write(s, "/W ", 3);
104	/* send the name followed by <CR><LF> */
105	(void)write(s, name, strlen(name));
106	(void)write(s, "\r\n", 2);
107
108	/*
109	 * Read from the remote system; once we're connected, we assume some
110	 * data.  If none arrives, we hang until the user interrupts.
111	 *
112	 * If we see a <CR> or a <CR> with the high bit set, treat it as
113	 * a newline; if followed by a newline character, only output one
114	 * newline.
115	 *
116	 * Otherwise, all high bits are stripped; if it isn't printable and
117	 * it isn't a space, we can simply set the 7th bit.  Every ASCII
118	 * character with bit 7 set is printable.
119	 */
120	if ((fp = fdopen(s, "r")) != NULL)
121		while ((c = getc(fp)) != EOF) {
122			c &= 0x7f;
123			if (c == '\r') {
124				if (lastc == '\r')
125					continue;
126				c = '\n';
127				lastc = '\r';
128			} else {
129				if (!isprint(c) && !isspace(c))
130					c |= 0x40;
131				if (lastc != '\r' || c != '\n')
132					lastc = c;
133				else {
134					lastc = '\n';
135					continue;
136				}
137			}
138			putchar(c);
139		}
140	if (lastc != '\n')
141		putchar('\n');
142	(void)fclose(fp);
143}
144