-
Notifications
You must be signed in to change notification settings - Fork 2.3k
/
nmap_ftp.cc
421 lines (393 loc) · 18.9 KB
/
nmap_ftp.cc
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
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
/***************************************************************************
* nmap_ftp.cc -- Nmap's FTP routines used for FTP bounce scan (-b)
* *
***********************IMPORTANT NMAP LICENSE TERMS************************
* *
* The Nmap Security Scanner is (C) 1996-2016 Insecure.Com LLC. Nmap is *
* also a registered trademark of Insecure.Com LLC. This program is free *
* software; you may redistribute and/or modify it under the terms of the *
* GNU General Public License as published by the Free Software *
* Foundation; Version 2 ("GPL"), BUT ONLY WITH ALL OF THE CLARIFICATIONS *
* AND EXCEPTIONS DESCRIBED HEREIN. This guarantees your right to use, *
* modify, and redistribute this software under certain conditions. If *
* you wish to embed Nmap technology into proprietary software, we sell *
* alternative licenses (contact [email protected]). Dozens of software *
* vendors already license Nmap technology such as host discovery, port *
* scanning, OS detection, version detection, and the Nmap Scripting *
* Engine. *
* *
* Note that the GPL places important restrictions on "derivative works", *
* yet it does not provide a detailed definition of that term. To avoid *
* misunderstandings, we interpret that term as broadly as copyright law *
* allows. For example, we consider an application to constitute a *
* derivative work for the purpose of this license if it does any of the *
* following with any software or content covered by this license *
* ("Covered Software"): *
* *
* o Integrates source code from Covered Software. *
* *
* o Reads or includes copyrighted data files, such as Nmap's nmap-os-db *
* or nmap-service-probes. *
* *
* o Is designed specifically to execute Covered Software and parse the *
* results (as opposed to typical shell or execution-menu apps, which will *
* execute anything you tell them to). *
* *
* o Includes Covered Software in a proprietary executable installer. The *
* installers produced by InstallShield are an example of this. Including *
* Nmap with other software in compressed or archival form does not *
* trigger this provision, provided appropriate open source decompression *
* or de-archiving software is widely available for no charge. For the *
* purposes of this license, an installer is considered to include Covered *
* Software even if it actually retrieves a copy of Covered Software from *
* another source during runtime (such as by downloading it from the *
* Internet). *
* *
* o Links (statically or dynamically) to a library which does any of the *
* above. *
* *
* o Executes a helper program, module, or script to do any of the above. *
* *
* This list is not exclusive, but is meant to clarify our interpretation *
* of derived works with some common examples. Other people may interpret *
* the plain GPL differently, so we consider this a special exception to *
* the GPL that we apply to Covered Software. Works which meet any of *
* these conditions must conform to all of the terms of this license, *
* particularly including the GPL Section 3 requirements of providing *
* source code and allowing free redistribution of the work as a whole. *
* *
* As another special exception to the GPL terms, Insecure.Com LLC grants *
* permission to link the code of this program with any version of the *
* OpenSSL library which is distributed under a license identical to that *
* listed in the included docs/licenses/OpenSSL.txt file, and distribute *
* linked combinations including the two. *
* *
* Any redistribution of Covered Software, including any derived works, *
* must obey and carry forward all of the terms of this license, including *
* obeying all GPL rules and restrictions. For example, source code of *
* the whole work must be provided and free redistribution must be *
* allowed. All GPL references to "this License", are to be treated as *
* including the terms and conditions of this license text as well. *
* *
* Because this license imposes special exceptions to the GPL, Covered *
* Work may not be combined (even as part of a larger work) with plain GPL *
* software. The terms, conditions, and exceptions of this license must *
* be included as well. This license is incompatible with some other open *
* source licenses as well. In some cases we can relicense portions of *
* Nmap or grant special permissions to use it in other open source *
* software. Please contact [email protected] with any such requests. *
* Similarly, we don't incorporate incompatible open source software into *
* Covered Software without special permission from the copyright holders. *
* *
* If you have any questions about the licensing restrictions on using *
* Nmap in other works, are happy to help. As mentioned above, we also *
* offer alternative license to integrate Nmap into proprietary *
* applications and appliances. These contracts have been sold to dozens *
* of software vendors, and generally include a perpetual license as well *
* as providing for priority support and updates. They also fund the *
* continued development of Nmap. Please email [email protected] for further *
* information. *
* *
* If you have received a written license agreement or contract for *
* Covered Software stating terms other than these, you may choose to use *
* and redistribute Covered Software under those terms instead of these. *
* *
* Source is provided to this software because we believe users have a *
* right to know exactly what a program is going to do before they run it. *
* This also allows you to audit the software for security holes. *
* *
* Source code also allows you to port Nmap to new platforms, fix bugs, *
* and add new features. You are highly encouraged to send your changes *
* to the [email protected] mailing list for possible incorporation into the *
* main distribution. By sending these changes to Fyodor or one of the *
* Insecure.Org development mailing lists, or checking them into the Nmap *
* source code repository, it is understood (unless you specify otherwise) *
* that you are offering the Nmap Project (Insecure.Com LLC) the *
* unlimited, non-exclusive right to reuse, modify, and relicense the *
* code. Nmap will always be available Open Source, but this is important *
* because the inability to relicense code has caused devastating problems *
* for other Free Software projects (such as KDE and NASM). We also *
* occasionally relicense the code to third parties as discussed above. *
* If you wish to specify special license conditions of your *
* contributions, just say so when you send them. *
* *
* This program is distributed in the hope that it will be useful, but *
* WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the Nmap *
* license file for more details (it's in a COPYING file included with *
* Nmap, and also available from https://svn.nmap.org/nmap/COPYING) *
* *
***************************************************************************/
/* $Id$ */
#include "nmap.h"
#include "nmap_ftp.h"
#include "output.h"
#include "NmapOps.h"
#include "nmap_error.h"
#include "tcpip.h"
#include "Target.h"
#include "nmap_tty.h"
extern NmapOps o;
struct ftpinfo get_default_ftpinfo(void) {
#if (defined(IN_ADDR_DEEPSTRUCT) || defined(SOLARIS))
/* Note that struct in_addr in solaris is 3 levels deep just to store an
* unsigned int! */
struct ftpinfo ftp = { FTPUSER, FTPPASS, "", { { { 0 } } } , 21, 0};
#else
struct ftpinfo ftp = { FTPUSER, FTPPASS, "", { 0 }, 21, 0};
#endif
return ftp;
}
/* parse a URL stype ftp string of the form user:pass@server:portno */
int parse_bounce_argument(struct ftpinfo *ftp, char *url) {
char *p = url, *q, *s;
if ((q = strrchr(url, '@'))) { /* we have user and/or pass */
*q++ = '\0';
if ((s = strchr(p, ':'))) { /* we have user AND pass */
*s++ = '\0';
strncpy(ftp->pass, s, 255);
} else { /* we ONLY have user */
log_write(LOG_STDOUT, "Assuming %s is a username, and using the default password: %s\n",
p, ftp->pass);
}
strncpy(ftp->user, p, 63);
} else {
q = url;
}
/* q points to beginning of server name */
if ((s = strchr(q, ':'))) { /* we have portno */
*s++ = '\0';
ftp->port = atoi(s);
}
strncpy(ftp->server_name, q, FQDN_LEN+1);
ftp->user[63] = ftp->pass[255] = ftp->server_name[FQDN_LEN] = 0;
return 1;
}
int ftp_anon_connect(struct ftpinfo *ftp) {
int sd;
struct sockaddr_in sock;
int res;
char recvbuf[2048];
char command[512];
if (o.verbose || o.debugging)
log_write(LOG_STDOUT, "Attempting connection to ftp:https://%s:%s@%s:%i\n",
ftp->user, ftp->pass, ftp->server_name, ftp->port);
if ((sd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
gh_perror("Couldn't create %s socket", __func__);
return 0;
}
socket_bindtodevice(sd, o.device);
sock.sin_family = AF_INET;
sock.sin_addr.s_addr = ftp->server.s_addr;
sock.sin_port = htons(ftp->port);
res = connect(sd, (struct sockaddr *) &sock, sizeof(struct sockaddr_in));
if (res < 0)
fatal("Your FTP bounce proxy server won't talk to us!");
if (o.verbose || o.debugging)
log_write(LOG_STDOUT, "Connected:");
while ((res = recvtime(sd, recvbuf, sizeof(recvbuf) - 1, 7, NULL)) > 0) {
if (o.debugging || o.verbose) {
recvbuf[res] = '\0';
log_write(LOG_STDOUT, "%s", recvbuf);
}
}
if (res < 0)
pfatal("recv problem from FTP bounce server");
Snprintf(command, 511, "USER %s\r\n", ftp->user);
send(sd, command, strlen(command), 0);
res = recvtime(sd, recvbuf, sizeof(recvbuf) - 1, 12, NULL);
if (res <= 0)
pfatal("recv problem from FTP bounce server");
recvbuf[res] = '\0';
if (o.debugging)
log_write(LOG_STDOUT, "sent username, received: %s", recvbuf);
if (recvbuf[0] == '5')
fatal("Your FTP bounce server doesn't like the username \"%s\"", ftp->user);
if (!strncmp(recvbuf, "230", 3)) {
// 230 User logged in
// No need to send PASS
if (o.verbose)
log_write(LOG_STDOUT, "Login credentials accepted by FTP server!\n");
ftp->sd = sd;
return sd;
}
Snprintf(command, 511, "PASS %s\r\n", ftp->pass);
send(sd, command, strlen(command), 0);
res = recvtime(sd, recvbuf, sizeof(recvbuf) - 1, 12, NULL);
if (res < 0)
pfatal("recv problem from FTP bounce server");
if (!res) {
error("Timeout from bounce server ...");
} else {
recvbuf[res] = '\0';
if (o.debugging)
log_write(LOG_STDOUT, "sent password, received: %s", recvbuf);
if (recvbuf[0] == '5')
fatal("Your FTP bounce server refused login combo (%s/%s)", ftp->user, ftp->pass);
}
while ((res = recvtime(sd, recvbuf, sizeof(recvbuf) - 1, 2, NULL)) > 0) {
if (o.debugging) {
recvbuf[res] = '\0';
log_write(LOG_STDOUT, "%s", recvbuf);
}
}
if (res < 0)
pfatal("recv problem from FTP bounce server");
if (o.verbose)
log_write(LOG_STDOUT, "Login credentials accepted by FTP server!\n");
ftp->sd = sd;
return sd;
}
/* FTP bounce attack scan. This function is rather lame and should be
rewritten. But I don't think it is used much anyway. If I'm going to
allow FTP bounce scan, I should really allow SOCKS proxy scan. */
void bounce_scan(Target *target, u16 *portarray, int numports,
struct ftpinfo *ftp) {
o.current_scantype = BOUNCE_SCAN;
ScanProgressMeter *SPM;
int res , sd = ftp->sd, i = 0;
const char *t = (const char *)target->v4hostip();
int retriesleft = FTP_RETRIES;
char recvbuf[2048];
char targetstr[20];
char command[512];
unsigned short portno, p1, p2;
int timedout;
bool privok = false;
if (numports == 0)
return; /* nothing to scan for */
Snprintf(targetstr, 20, "%d,%d,%d,%d,", UC(t[0]), UC(t[1]), UC(t[2]), UC(t[3]));
SPM = new ScanProgressMeter(scantype2str(BOUNCE_SCAN));
for (i = 0; i < numports; i++) {
/* Check for timeout */
if (target->timedOut(NULL)) {
Snprintf(recvbuf, sizeof(recvbuf), "Target timed out");
SPM->endTask(NULL, recvbuf);
delete SPM;
return;
}
portno = htons(portarray[i]);
p1 = ((unsigned char *) &portno)[0];
p2 = ((unsigned char *) &portno)[1];
Snprintf(command, 512, "PORT %s%i,%i\r\n", targetstr, p1, p2);
if (o.debugging)
log_write(LOG_STDOUT, "Attempting command: %s", command);
if (send(sd, command, strlen(command), 0) < 0 ) {
gh_perror("send in %s", __func__);
if (retriesleft) {
if (o.verbose || o.debugging)
log_write(LOG_STDOUT, "Our FTP proxy server hung up on us! retrying\n");
retriesleft--;
close(sd);
ftp->sd = ftp_anon_connect(ftp);
if (ftp->sd < 0) {
Snprintf(recvbuf, sizeof(recvbuf), "Error connecting");
SPM->endTask(NULL, recvbuf);
delete SPM;
return;
}
sd = ftp->sd;
i--;
} else {
error("Our socket descriptor is dead and we are out of retries. Giving up.");
close(sd);
ftp->sd = -1;
Snprintf(recvbuf, sizeof(recvbuf), "Max retries exceeded");
SPM->endTask(NULL, recvbuf);
delete SPM;
return;
}
} else { /* Our send is good */
res = recvtime(sd, recvbuf, 2048, 15, NULL);
if (res <= 0) {
perror("recv problem from FTP bounce server");
} else { /* our recv is good */
recvbuf[res] = '\0';
if (o.debugging)
log_write(LOG_STDOUT, "result of port query on port %i: %s",
portarray[i], recvbuf);
if (recvbuf[0] == '5' && !privok) {
if (portarray[i] > 1023) {
fatal("Your FTP bounce server sucks, it won't let us feed bogus ports!");
} else {
error("Your FTP bounce server doesn't allow privileged ports, skipping them.");
while (i < numports && portarray[i] < 1024) i++;
if (i >= numports) {
fatal("And you didn't want to scan any unprivileged ports. Giving up.");
}
}
} else { /* Not an error message */
if (portarray[i] < 1024) {
privok = true;
}
if (send(sd, "LIST\r\n", 6, 0) > 0 ) {
res = recvtime(sd, recvbuf, 2048, 12, &timedout);
if (res < 0) {
perror("recv problem from FTP bounce server");
} else if (res == 0) {
recvbuf[res] = '\0';
if (timedout)
target->ports.setPortState(portarray[i], IPPROTO_TCP, PORT_FILTERED);
else target->ports.setPortState(portarray[i], IPPROTO_TCP, PORT_CLOSED);
} else {
recvbuf[res] = '\0';
if (o.debugging)
log_write(LOG_STDOUT, "result of LIST: %s", recvbuf);
if (!strncmp(recvbuf, "500", 3)) {
/* oh dear, we are not aligned properly */
if (o.verbose || o.debugging)
error("FTP command misalignment detected ... correcting.");
res = recvtime(sd, recvbuf, 2048, 10, NULL);
}
if (recvbuf[0] == '1') {
res = recvtime(sd, recvbuf, 2048, 10, &timedout);
if (res < 0)
perror("recv problem from FTP bounce server");
else if (timedout || res == 0) {
// Timed out waiting for LIST to complete; probably filtered.
if(send(sd, "ABOR\r\n", 6, 0) > 0) {
target->ports.setPortState(portarray[i], IPPROTO_TCP, PORT_FILTERED);
}
// Get response and discard
res = recvtime(sd, recvbuf, 2048, 10, &timedout);
recvbuf[0] = '\0';
goto nextport;
}
else {
recvbuf[res] = '\0';
if (res > 0) {
if (o.debugging)
log_write(LOG_STDOUT, "nxt line: %s", recvbuf);
if (recvbuf[0] == '4' && recvbuf[1] == '2' && recvbuf[2] == '6') {
target->ports.forgetPort(portarray[i], IPPROTO_TCP);
if (o.debugging || o.verbose)
log_write(LOG_STDOUT, "Changed my mind about port %i\n", portarray[i]);
}
}
}
}
if (recvbuf[0] == '2') {
target->ports.setPortState(portarray[i], IPPROTO_TCP, PORT_OPEN);
} else {
/* This means the port is closed ... */
target->ports.setPortState(portarray[i], IPPROTO_TCP, PORT_CLOSED);
}
}
}
}
}
}
nextport:
if (SPM->mayBePrinted(NULL)) {
SPM->printStatsIfNecessary((double) i / numports, NULL);
}
else if (keyWasPressed()) {
SPM->printStats((double) i / numports, NULL);
log_flush(LOG_STDOUT);
}
}
Snprintf(recvbuf, sizeof(recvbuf), "%d total ports", numports);
SPM->endTask(NULL, recvbuf);
delete SPM;
return;
}