summaryrefslogtreecommitdiff
path: root/networking/whois.c
blob: 6ba8dfd2009892dc3244065a9f27cfe9b4a8a3db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
/* vi: set sw=4 ts=4: */
/*
 * whois - tiny client for the whois directory service
 *
 * Copyright (c) 2011 Pere Orga <gotrunks@gmail.com>
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
/* TODO
 * Add ipv6 support
 * Add proxy support
 */

//config:config WHOIS
//config:	bool "whois"
//config:	default y
//config:	help
//config:	  whois is a client for the whois directory service

//applet:IF_WHOIS(APPLET(whois, BB_DIR_USR_BIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_WHOIS) += whois.o

//usage:#define whois_trivial_usage
//usage:       "[-i] [-h SERVER] [-p PORT] NAME..."
//usage:#define whois_full_usage "\n\n"
//usage:       "Query WHOIS info about NAME\n"
//usage:     "\n	-i	Show redirect results too"
//usage:     "\n	-h,-p	Server to query"

#include "libbb.h"

enum {
	OPT_i = (1 << 0),
};

static char *query(const char *host, int port, const char *domain)
{
	int fd;
	FILE *fp;
	bool success;
	char *redir = NULL;
	const char *pfx = "";
	char linebuf[1024];
	char *buf = NULL;
	unsigned bufpos = 0;

 again:
	printf("[Querying %s:%d '%s%s']\n", host, port, pfx, domain);
	fd = create_and_connect_stream_or_die(host, port);
	success = 0;
	fdprintf(fd, "%s%s\r\n", pfx, domain);
	fp = xfdopen_for_read(fd);

	while (fgets(linebuf, sizeof(linebuf), fp)) {
		unsigned len = strcspn(linebuf, "\r\n");
		linebuf[len++] = '\n';

		buf = xrealloc(buf, bufpos + len + 1);
		memcpy(buf + bufpos, linebuf, len);
		bufpos += len;
		buf[bufpos] = '\0';

		if (!redir || !success) {
			trim(linebuf);
			str_tolower(linebuf);
			if (!success) {
				success = is_prefixed_with(linebuf, "domain:")
				       || is_prefixed_with(linebuf, "domain name:");
			}
			else if (!redir) {
				char *p = is_prefixed_with(linebuf, "whois server:");
				if (!p)
					p = is_prefixed_with(linebuf, "whois:");
				if (p)
					redir = xstrdup(skip_whitespace(p));
			}
		}
	}
	fclose(fp); /* closes fd too */
	if (!success && !pfx[0]) {
		/*
		 * Looking at /etc/jwhois.conf, some whois servers use
		 * "domain = DOMAIN", "DOMAIN ID <DOMAIN>"
		 * and "domain=DOMAIN_WITHOUT_LAST_COMPONENT"
		 * formats, but those are rare.
		 * (There are a few even more contrived ones.)
		 * We are trying only "domain DOMAIN", the typical one.
		 */
		pfx = "domain ";
		bufpos = 0;
		goto again;
	}

	/* Success */
	if (redir && strcmp(redir, host) == 0) {
		/* Redirect to self does not count */
		free(redir);
		redir = NULL;
	}
	if (!redir || (option_mask32 & OPT_i)) {
		/* Output saved text */
		printf("[%s]\n%s", host, buf ? buf : "");
	}
	free(buf);
	return redir;
}

static void recursive_query(const char *host, int port, const char *domain)
{
	char *free_me = NULL;
	char *redir;
 again:
	redir = query(host, port, domain);
	free(free_me);
	if (redir) {
		printf("[Redirected to %s]\n", redir);
		host = free_me = redir;
		port = 43;
		goto again;
	}
}

/* One of "big" whois implementations has these options:
 *
 * $ whois --help
 * jwhois version 4.0, Copyright (C) 1999-2007  Free Software Foundation, Inc.
 * -v, --verbose              verbose debug output
 * -c FILE, --config=FILE     use FILE as configuration file
 * -h HOST, --host=HOST       explicitly query HOST
 * -n, --no-redirect          disable content redirection
 * -s, --no-whoisservers      disable whois-servers.net service support
 * -a, --raw                  disable reformatting of the query
 * -i, --display-redirections display all redirects instead of hiding them
 * -p PORT, --port=PORT       use port number PORT (in conjunction with HOST)
 * -r, --rwhois               force an rwhois query to be made
 * --rwhois-display=DISPLAY   sets the display option in rwhois queries
 * --rwhois-limit=LIMIT       sets the maximum number of matches to return
 *
 * Example of its output:
 * $ whois cnn.com
 * [Querying whois.verisign-grs.com]
 * [Redirected to whois.corporatedomains.com]
 * [Querying whois.corporatedomains.com]
 * [whois.corporatedomains.com]
 * ...text of the reply...
 *
 * With -i, reply from each server is printed, after all redirects are done:
 * [Querying whois.verisign-grs.com]
 * [Redirected to whois.corporatedomains.com]
 * [Querying whois.corporatedomains.com]
 * [whois.verisign-grs.com]
 * ...text of the reply...
 * [whois.corporatedomains.com]
 * ...text of the reply...
 *
 * With -a, no "DOMAIN" -> "domain DOMAIN" transformation is attempted.

 * With -n, the first reply is shown, redirects are not followed:
 * [Querying whois.verisign-grs.com]
 * [whois.verisign-grs.com]
 * ...text of the reply...
 */

int whois_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int whois_main(int argc UNUSED_PARAM, char **argv)
{
	int port = 43;
	const char *host = "whois.iana.org";

	opt_complementary = "-1:p+";
	getopt32(argv, "ih:p:", &host, &port);
	argv += optind;

	do {
		recursive_query(host, port, *argv);
	}
	while (*++argv);

	return EXIT_SUCCESS;
}