/*************************************************************************** * ncrack_ftp.cc -- ncrack module for the FTP protocol * * * ***********************IMPORTANT NMAP LICENSE TERMS************************ * * * The Nmap Security Scanner is (C) 1996-2011 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 with the clarifications and exceptions described * * below. 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 sales@insecure.com). Dozens of software vendors already * * license Nmap technology such as host discovery, port scanning, OS * * detection, and version detection. * * * * Note that the GPL places important restrictions on "derived works", yet * * it does not provide a detailed definition of that term. To avoid * * misunderstandings, we consider an application to constitute a * * "derivative work" for the purpose of this license if it does any of the * * following: * * o Integrates source code from Nmap * * o Reads or includes Nmap copyrighted data files, such as * * nmap-os-db or nmap-service-probes. * * o Executes Nmap and parses the results (as opposed to typical shell or * * execution-menu apps, which simply display raw Nmap output and so are * * not derivative works.) * * o Integrates/includes/aggregates Nmap into a proprietary executable * * installer, such as those produced by InstallShield. * * o Links to a library or executes a program that does any of the above * * * * The term "Nmap" should be taken to also include any portions or derived * * works of Nmap. This list is not exclusive, but is meant to clarify our * * interpretation of derived works with some common examples. Our * * interpretation applies only to Nmap--we don't speak for other people's * * GPL works. * * * * If you have any questions about the GPL licensing restrictions on using * * Nmap in non-GPL works, we would be 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 as well as helping to * * fund the continued development of Nmap technology. Please email * * sales@insecure.com for further information. * * * * As a 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. 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By sending these changes to Fyodor or one of the * * Insecure.Org development mailing lists, it is assumed 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 GNU * * General Public License v2.0 for more details at * * http://www.gnu.org/licenses/gpl-2.0.html , or in the COPYING file * * included with Nmap. * * * ***************************************************************************/ #include "ncrack.h" #include "nsock.h" #include "NcrackOps.h" #include "Service.h" #include "modules.h" #define FTP_TIMEOUT 20000 #define FTP_DIGITS 3 extern NcrackOps o; extern void ncrack_read_handler(nsock_pool nsp, nsock_event nse, void *mydata); extern void ncrack_write_handler(nsock_pool nsp, nsock_event nse, void *mydata); extern void ncrack_module_end(nsock_pool nsp, void *mydata); static int ftp_loop_read(nsock_pool nsp, Connection *con); enum states { FTP_INIT, FTP_USER, FTP_FINI }; static int ftp_loop_read(nsock_pool nsp, Connection *con, char *ftp_code_ret) { int i; int ftp_dig[FTP_DIGITS]; char ftp_code[FTP_DIGITS + 2]; /* 3 digits + space + '\0' */ char dig[2]; /* temporary digit string */ char *p; if (con->inbuf == NULL || con->inbuf->get_len() < FTP_DIGITS + 1) { nsock_read(nsp, con->niod, ncrack_read_handler, FTP_TIMEOUT, con); return -1; } /* Make sure first 3 (FTP_DIGITS) bytes of each line are digits */ p = (char *)con->inbuf->get_dataptr(); dig[1] = '\0'; for (i = 0; i < FTP_DIGITS; i++) { dig[0] = *p++; ftp_dig[i] = (int)Strtoul(dig, 0); if (errno) { /* It wasn't a number! */ return -2; /* Oops, malformed FTP packet */ } } /* * http://www.faqs.org/rfcs/rfc959.html * Thus the format for multi-line replies is that the first line * will begin with the exact required reply code, followed * immediately by a Hyphen, "-" (also known as Minus), followed by * text. The last line will begin with the same code, followed * immediately by Space , optionally some text, and the Telnet * end-of-line code. * * For example: * 123-First line * Second line * 234 A line beginning with numbers * 123 The last line */ /* Convert digits to string code for parsing */ snprintf(ftp_code, FTP_DIGITS + 1, "%d%d%d", ftp_dig[0], ftp_dig[1], ftp_dig[2]); ftp_code[FTP_DIGITS] = ' '; ftp_code[FTP_DIGITS + 1] = '\0'; if (*p == '-') { /* FTP message is multiple lines, so first search for the 'ftp code' to * find the last line, according to the scheme proposed by RFC 959 */ if (!(p = memsearch((const char *)con->inbuf->get_dataptr(), ftp_code, con->inbuf->get_len()))) { nsock_read(nsp, con->niod, ncrack_read_handler, FTP_TIMEOUT, con); return -1; } /* Now that we found the the last line, find that line's end */ if (!memsearch((const char *)p, "\r\n", con->inbuf->get_len())) { nsock_read(nsp, con->niod, ncrack_read_handler, FTP_TIMEOUT, con); return -1; } } else { /* FTP message is one line only */ if (!memsearch((const char *)con->inbuf->get_dataptr(), "\r\n", con->inbuf->get_len())) { nsock_read(nsp, con->niod, ncrack_read_handler, FTP_TIMEOUT, con); return -1; } } /* Return the ftp code to caller */ strncpy(ftp_code_ret, ftp_code, FTP_DIGITS); return 0; } void ncrack_ftp(nsock_pool nsp, Connection *con) { nsock_iod nsi = con->niod; Service *serv = con->service; const char *hostinfo = serv->HostInfo(); char ftp_code[FTP_DIGITS + 1]; memset(ftp_code, 0, sizeof(ftp_code)); switch (con->state) { case FTP_INIT: /* Wait to read banner only at the beginning of the connection */ if (!con->login_attempts) { if (ftp_loop_read(nsp, con, ftp_code) < 0) break; /* ftp_loop_read already takes care so that the inbuf contains the * 3 first ftp digit code, so you can safely traverse it that much */ if (strncmp(ftp_code, "220", FTP_DIGITS)) { if (o.debugging > 6) error("%s Not ftp or service was shutdown\n", hostinfo); return ncrack_module_end(nsp, con); } } con->state = FTP_USER; delete con->inbuf; con->inbuf = NULL; if (con->outbuf) delete con->outbuf; con->outbuf = new Buf(); con->outbuf->snprintf(7 + strlen(con->user), "USER %s\r\n", con->user); nsock_write(nsp, nsi, ncrack_write_handler, FTP_TIMEOUT, con, (const char *)con->outbuf->get_dataptr(), con->outbuf->get_len()); break; case FTP_USER: if (ftp_loop_read(nsp, con, ftp_code) < 0) break; if (!strncmp(ftp_code, "331", FTP_DIGITS)) { ; } else { return ncrack_module_end(nsp, con); } con->state = FTP_FINI; delete con->inbuf; con->inbuf = NULL; if (con->outbuf) delete con->outbuf; con->outbuf = new Buf(); con->outbuf->snprintf(7 + strlen(con->pass), "PASS %s\r\n", con->pass); nsock_write(nsp, nsi, ncrack_write_handler, FTP_TIMEOUT, con, (const char *)con->outbuf->get_dataptr(), con->outbuf->get_len()); break; case FTP_FINI: if (ftp_loop_read(nsp, con, ftp_code) < 0) break; if (!strncmp(ftp_code, "230", FTP_DIGITS)) con->auth_success = true; con->state = FTP_INIT; delete con->inbuf; con->inbuf = NULL; return ncrack_module_end(nsp, con); } /* make sure that ncrack_module_end() is always called last or returned to * have tail recursion or else stack space overflow might occur */ }