path: root/networking/whois.c (plain)
blob: c9dfcf5ee424396fcf1ecfcf55b0f810868b8572

1	/* vi: set sw=4 ts=4: */
2	/*
3	* whois - tiny client for the whois directory service
4	*
5	* Copyright (c) 2011 Pere Orga <gotrunks@gmail.com>
6	* Licensed under GPLv2 or later, see file LICENSE in this source tree.
7	*/
8	/* TODO
9	* Add ipv6 support
10	* Add proxy support
11	*/
12
13	//config:config WHOIS
14	//config: bool "whois"
15	//config: default y
16	//config: help
17	//config: whois is a client for the whois directory service
18
19	//applet:IF_WHOIS(APPLET(whois, BB_DIR_USR_BIN, BB_SUID_DROP))
20
21	//kbuild:lib-$(CONFIG_WHOIS) += whois.o
22
23	//usage:#define whois_trivial_usage
24	//usage: "[-i] [-h SERVER] [-p PORT] NAME..."
25	//usage:#define whois_full_usage "\n\n"
26	//usage: "Query WHOIS info about NAME\n"
27	//usage: "\n -i Show redirect results too"
28	//usage: "\n -h,-p Server to query"
29
30	#include "libbb.h"
31
32	enum {
33	OPT_i = (1 << 0),
34	};
35
36	static char *query(const char *host, int port, const char *domain)
37	{
38	int fd;
39	FILE *fp;
40	bool success;
41	char *redir = NULL;
42	const char *pfx = "";
43	char linebuf[1024];
44	char *buf = NULL;
45	unsigned bufpos = 0;
46
47	again:
48	printf("[Querying %s:%d '%s%s']\n", host, port, pfx, domain);
49	fd = create_and_connect_stream_or_die(host, port);
50	success = 0;
51	fdprintf(fd, "%s%s\r\n", pfx, domain);
52	fp = xfdopen_for_read(fd);
53
54	while (fgets(linebuf, sizeof(linebuf), fp)) {
55	unsigned len = strcspn(linebuf, "\r\n");
56	linebuf[len++] = '\n';
57
58	buf = xrealloc(buf, bufpos + len + 1);
59	memcpy(buf + bufpos, linebuf, len);
60	bufpos += len;
61	buf[bufpos] = '\0';
62
63	if (!redir || !success) {
64	trim(linebuf);
65	str_tolower(linebuf);
66	if (!success) {
67	success = is_prefixed_with(linebuf, "domain:")
68	|| is_prefixed_with(linebuf, "domain name:");
69	}
70	else if (!redir) {
71	char *p = is_prefixed_with(linebuf, "whois server:");
72	if (!p)
73	p = is_prefixed_with(linebuf, "whois:");
74	if (p)
75	redir = xstrdup(skip_whitespace(p));
76	}
77	}
78	}
79	fclose(fp); /* closes fd too */
80	if (!success && !pfx[0]) {
81	/*
82	* Looking at /etc/jwhois.conf, some whois servers use
83	* "domain = DOMAIN", "DOMAIN ID <DOMAIN>"
84	* and "domain=DOMAIN_WITHOUT_LAST_COMPONENT"
85	* formats, but those are rare.
86	* (There are a few even more contrived ones.)
87	* We are trying only "domain DOMAIN", the typical one.
88	*/
89	pfx = "domain ";
90	bufpos = 0;
91	goto again;
92	}
93
94	/* Success */
95	if (redir && strcmp(redir, host) == 0) {
96	/* Redirect to self does not count */
97	free(redir);
98	redir = NULL;
99	}
100	if (!redir || (option_mask32 & OPT_i)) {
101	/* Output saved text */
102	printf("[%s]\n%s", host, buf ? buf : "");
103	}
104	free(buf);
105	return redir;
106	}
107
108	static void recursive_query(const char *host, int port, const char *domain)
109	{
110	char *free_me = NULL;
111	char *redir;
112	again:
113	redir = query(host, port, domain);
114	free(free_me);
115	if (redir) {
116	printf("[Redirected to %s]\n", redir);
117	host = free_me = redir;
118	port = 43;
119	goto again;
120	}
121	}
122
123	/* One of "big" whois implementations has these options:
124	*
125	* $ whois --help
126	* jwhois version 4.0, Copyright (C) 1999-2007 Free Software Foundation, Inc.
127	* -v, --verbose verbose debug output
128	* -c FILE, --config=FILE use FILE as configuration file
129	* -h HOST, --host=HOST explicitly query HOST
130	* -n, --no-redirect disable content redirection
131	* -s, --no-whoisservers disable whois-servers.net service support
132	* -a, --raw disable reformatting of the query
133	* -i, --display-redirections display all redirects instead of hiding them
134	* -p PORT, --port=PORT use port number PORT (in conjunction with HOST)
135	* -r, --rwhois force an rwhois query to be made
136	* --rwhois-display=DISPLAY sets the display option in rwhois queries
137	* --rwhois-limit=LIMIT sets the maximum number of matches to return
138	*
139	* Example of its output:
140	* $ whois cnn.com
141	* [Querying whois.verisign-grs.com]
142	* [Redirected to whois.corporatedomains.com]
143	* [Querying whois.corporatedomains.com]
144	* [whois.corporatedomains.com]
145	* ...text of the reply...
146	*
147	* With -i, reply from each server is printed, after all redirects are done:
148	* [Querying whois.verisign-grs.com]
149	* [Redirected to whois.corporatedomains.com]
150	* [Querying whois.corporatedomains.com]
151	* [whois.verisign-grs.com]
152	* ...text of the reply...
153	* [whois.corporatedomains.com]
154	* ...text of the reply...
155	*
156	* With -a, no "DOMAIN" -> "domain DOMAIN" transformation is attempted.
157
158	* With -n, the first reply is shown, redirects are not followed:
159	* [Querying whois.verisign-grs.com]
160	* [whois.verisign-grs.com]
161	* ...text of the reply...
162	*/
163
164	int whois_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
165	int whois_main(int argc UNUSED_PARAM, char **argv)
166	{
167	int port = 43;
168	const char *host = "whois.iana.org";
169
170	opt_complementary = "-1";
171	getopt32(argv, "ih:p:+", &host, &port);
172	argv += optind;
173
174	do {
175	recursive_query(host, port, *argv);
176	}
177	while (*++argv);
178
179	return EXIT_SUCCESS;
180	}
181