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
47 void
netfinger(char * name)48 netfinger(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