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
181
182
183
184
185
|
From f8e33d70806d0dee740e5451aedfe5089a4d156a Mon Sep 17 00:00:00 2001
From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Wed, 6 Jul 2016 15:45:41 +0200
Subject: [PATCH 16/16] whois: make it actually work
It was doing way too simplistic work of just querying the server,
no redirects, no query massaging. This required user to know a lot about whois,
and enter at least three queries for each host to get meaningful information.
function old new delta
whois_main 209 646 +437
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
networking/whois.c | 137 ++++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 124 insertions(+), 13 deletions(-)
diff --git a/networking/whois.c b/networking/whois.c
index bf33033..5ef8367 100644
--- a/networking/whois.c
+++ b/networking/whois.c
@@ -28,36 +28,147 @@
#include "libbb.h"
-static void pipe_out(int fd)
+static char *query(const char *host, int port, const char *domain)
{
+ int fd;
FILE *fp;
- char buf[1024];
+ 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(buf, sizeof(buf), fp)) {
- char *p = strpbrk(buf, "\r\n");
- if (p)
- *p = '\0';
- puts(buf);
- }
+ 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;
+
+ 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 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) {
+ /* Output saved text */
+ printf("[%s]\n", host);
+ buf[bufpos] = '\0';
+ fputs(buf, stdout);
+ }
+ 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-servers.net";
+ const char *host = "whois.iana.org";
opt_complementary = "-1:p+";
getopt32(argv, "h:p:", &host, &port);
-
argv += optind;
+
do {
- int fd = create_and_connect_stream_or_die(host, port);
- fdprintf(fd, "%s\r\n", *argv);
- pipe_out(fd);
+ recursive_query(host, port, *argv);
}
while (*++argv);
--
2.9.1
|
