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
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
|
/* Copyright (c) 2002 Sam Trenholme
*
* TERMS
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* This software is provided 'as is' with no guarantees of correctness or
* fitness for purpose.
*/
/* This is a version of getzone which does not convert the raw data in to
MaraDNS' "csv1" zone file format; instead, it shows us the raw DNS
packets on standard out. Designed to be used to make input for
test_zoneserver.c
*/
/* Language-specific labels */
#include "../tcp/getzone_locale.h"
/* Other includes */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <signal.h>
#include "../MaraDns.h"
/* Function prototypes */
#include "../dns/functions_dns.h"
#include "../libs/MaraHash.h"
#include "../parse/functions_parse.h"
extern int decomp_init();
void harderror(char *why) {
printf("%s%s%s%s",LF,L_FATAL_COMMENT,why,LF); /* "\n", "# Fatal error: ", why, "\n" */
exit(3);
}
void timeout() {
harderror(L_TIMEOUT); /* "Connection timed out" */
}
/* OK, get a load of this. There are many older versions of
BIND out there that completely, I mean, completely ignore the
RFCs. Instead of sending a compressed DNS packet, it sends
a single resource record which it considers a "DNS packet".
The only way to search for this is to see if the first part
of the message is a DNS packet. Since this behavior is
not RFC complient, the "is this a buggy bind 8 packet"
seacher will only allow /[A-Z][a-z][0-9]\-\_/ (perl5 regex)
in a DNS name (we include _ because too many Microsoft shops
have _ in their computer names)
Input: A potential BIND-buggy DNS packet
Output: 0 if it looks RFC complient, 1 if it's a !@#$ BIND4/8 packet,
and -1 (JS_ERROR) if the sky fell down (actually, we just assume
that it is a normal DNS packet with data which happens to look
like a demented dlabel packet)
*/
int bind_bug_check(js_string *packet) {
int place, len;
place = 0;
len = *packet->string;
if(len <= 0 || len >= 64)
return 0; /* This doesn't mean it's kosher; just that it is
not the kind of trash Bind 8 spews */
while(len > 0 && len < 64) {
while(len > 0) {
unsigned char fina; /* Yes, I am pathetic enough to name
variables after whatever beautiful
latina has last caught my fancy */
len--;
place++;
if(place > packet->unit_count || place > packet->max_count)
return 1; /* Again, doesn't mean it's kosher */
/* The /[A-Z][a-z][0-9]\-_/ regex; I'm doing this by
sorting the regex in ASCII order and stopping if
something is in a "hole" outside the regex 'cause I
am too tired right now to do a big and/or expression */
fina = *(packet->string + place);
if(fina < '-') /* The first ASCII character in this regex */
return 1;
if(fina > '-' && fina < '0')
return 1;
if(fina > '9' && fina < 'A')
return 1;
if(fina > 'Z' && fina < '_')
return 1;
if(fina > '_' && fina < 'a')
return 1;
if(fina > 'z') /* UTF-8 in domain names would probably be
a reasonable option if BIND was not the
dominant DNS server out there */
return 1;
/* End of regex */
}
len = *(packet->string + place);
}
if(len == 0)
return 0;
return 1;
}
/* Usage: getzone <zone name> <zone server IP> */
int main(int argc, char **argv) {
int sock, preference;
int len_inet, length, place = 0, result;
int soa_count = 0;
struct sockaddr_in zone_server; /* AF_INET */
js_string *send, *zone, *get, *expand, *mxexpand;
/* ( Sending and getting data from the client ) */
q_header header;
q_rr rr;
rr_soa soa;
int qclass = 1;
unsigned char len[2];
if((argc < 3 && argc > 4) || argv[1] == 0 || argv[2] == 0) {
harderror(L_USAGE); /* "Usage: getzone zone_name zone_server_IP" */
}
if(argc == 4 && argv[3] == 0) {
harderror(L_USAGE); /* "Usage: getzone zone_name zone_server_IP" */
}
/* Set up an option to change the query class */
if(argc == 4 && atoi(argv[3]) == 255)
qclass = 255;
/* Create a timeout alarm */
signal(SIGALRM,timeout);
alarm(300); /* 5 minutes */
/* Create a socket to the zone server */
memset(&zone_server,0,sizeof zone_server);
zone_server.sin_family = AF_INET;
zone_server.sin_port = htons(53);
zone_server.sin_addr.s_addr = inet_addr(argv[2]);
if(zone_server.sin_addr.s_addr == INADDR_NONE)
harderror(L_VALID_IP); /* "Please use a valid IP for the zone server" */
len_inet = sizeof zone_server;
/* Create a TCP/IP socket */
sock = socket(PF_INET,SOCK_STREAM,0);
if(sock == -1)
harderror(L_NO_SOCK); /* "Unable to create TCP socket" */
/* Connect to the zone server */
if(connect(sock,(struct sockaddr *)&zone_server,len_inet) == -1)
harderror(L_NO_CONNECT); /* "Unable to connect to zone server" */
/* OK, create a query to send over the connection */
if((send = js_create(256,1)) == 0)
harderror(L_NO_SEND); /* "Unable to create send string object" */
/* The 12-byte header to send to the DNS server */
header.id = 45;
header.qr = 0;
header.opcode = 0;
header.aa = 0;
header.tc = 0;
header.rd = 0;
header.ra = 0;
header.z = 0;
header.rcode = 0;
header.qdcount = 1;
header.ancount = 0;
header.nscount = 0;
header.arcount = 0;
if(make_hdr(&header,send) == JS_ERROR)
harderror(L_NO_HEADER); /* "Unable to make DNS header" */
if((zone = js_create(128,1)) == 0)
harderror(L_NO_ZSTRING); /* "Unable to create zone string object" */
if(js_qstr2js(zone,"A") == JS_ERROR)
harderror(L_QSTR2JS_ERROR); /* "qstr2js" */
if(js_qappend(argv[1],zone) == JS_ERROR)
harderror(L_APPEND_Z); /* "Unable to append zone string to zone object" */
/* Append trailing dot, if needed */
if(*(zone->string + zone->unit_count - 1) != '.')
if(js_qappend(".",zone) == JS_ERROR)
harderror(L_APPEND_D); /* "Unable to append dot at end of zone string object" */
/* Convert zone in to raw "over-the-wire" UDP data */
if(hname_2rfc1035(zone) == JS_ERROR)
harderror(L_INVALID_NAME); /* "Invalid form of zone name" */
/* Append raw binary zone to data to send to server */
if(js_append(zone,send) == JS_ERROR)
harderror(L_APPEND_ZS); /* "Can not append zone string to send string" */
/* Append query type and query class to data */
if(js_adduint16(send,252) == JS_ERROR)
harderror(L_ADD_QT); /* "Could not add query type to send" */
if(js_adduint16(send,qclass) == JS_ERROR)
harderror(L_ADD_QC); /* "Could not add query class to send" */
/* Question formed, now send question to server */
len[0] = (send->unit_count & 0xff00) >> 8;
len[1] = send->unit_count & 0xff;
if(write(sock,len,2) == -1)
harderror(L_SEND_2BYTE); /* "Could not send 2-byte length header to zone server" */
if(write(sock,send->string,send->unit_count) == -1)
harderror(L_SEND_QUERY); /* "Could not send query to zone server" */
if((rr.name = js_create(257,1)) == 0)
harderror(L_C_RRNAME); /* "Could not create rr.name" */
if((soa.mname = js_create(257,1)) == 0)
harderror(L_MNAME); /* "Could not create soa.mname" */
if((soa.rname = js_create(257,1)) == 0)
harderror(L_RNAME); /* "Could not create soa.rname" */
while(recv(sock,len,2,MSG_WAITALL) == 2) {
int is_buggy_bind_packet = 0;
/* Get the length of the reply from the server */
length = ((len[0] << 8) & 0xff00) | (len[1] & 0xff);
if(length < 12)
harderror(L_NOT_MANLY); /* "Response from server is not long enough to hold header" */
/* Allocate the string "get" */
if((get = js_create(length + 7,1)) == 0)
harderror(L_NO_GET); /* "Could not allocate memory for get string" */
if((expand = js_create((length + 7) * 4,1)) == 0)
harderror(L_NO_EXPAND); /* "Could not allocate memory for expand string" */
if((length = recv(sock,get->string,length,MSG_WAITALL)) == -1)
harderror(L_SERVER); /* "Could not get packet from server" */
get->unit_count = length;
show_esc_stdout(get);
printf("\n");
fflush(stdout);
js_destroy(get);
}
return 0; /* Success */
}
|
