1 2 /*************************************************************************** 3 * Connection.h -- The "Connection" class holds information specifically * 4 * pertaining to connection probes. Objects of this class must always * 5 * belong to a certain "Service" object. * 6 * * 7 ***********************IMPORTANT NMAP LICENSE TERMS************************ 8 * * 9 * The Nmap Security Scanner is (C) 1996-2019 Insecure.Com LLC ("The Nmap * 10 * Project"). Nmap is also a registered trademark of the Nmap Project. * 11 * This program is free software; you may redistribute and/or modify it * 12 * under the terms of the GNU General Public License as published by the * 13 * Free Software Foundation; Version 2 ("GPL"), BUT ONLY WITH ALL OF THE * 14 * CLARIFICATIONS AND EXCEPTIONS DESCRIBED HEREIN. This guarantees your * 15 * right to use, modify, and redistribute this software under certain * 16 * conditions. If you wish to embed Nmap technology into proprietary * 17 * software, we sell alternative licenses (contact sales@nmap.com). * 18 * Dozens of software vendors already license Nmap technology such as * 19 * host discovery, port scanning, OS detection, version detection, and * 20 * the Nmap Scripting Engine. * 21 * * 22 * Note that the GPL places important restrictions on "derivative works", * 23 * yet it does not provide a detailed definition of that term. To avoid * 24 * misunderstandings, we interpret that term as broadly as copyright law * 25 * allows. For example, we consider an application to constitute a * 26 * derivative work for the purpose of this license if it does any of the * 27 * following with any software or content covered by this license * 28 * ("Covered Software"): * 29 * * 30 * o Integrates source code from Covered Software. * 31 * * 32 * o Reads or includes copyrighted data files, such as Nmap's nmap-os-db * 33 * or nmap-service-probes. * 34 * * 35 * o Is designed specifically to execute Covered Software and parse the * 36 * results (as opposed to typical shell or execution-menu apps, which will * 37 * execute anything you tell them to). * 38 * * 39 * o Includes Covered Software in a proprietary executable installer. The * 40 * installers produced by InstallShield are an example of this. Including * 41 * Nmap with other software in compressed or archival form does not * 42 * trigger this provision, provided appropriate open source decompression * 43 * or de-archiving software is widely available for no charge. For the * 44 * purposes of this license, an installer is considered to include Covered * 45 * Software even if it actually retrieves a copy of Covered Software from * 46 * another source during runtime (such as by downloading it from the * 47 * Internet). * 48 * * 49 * o Links (statically or dynamically) to a library which does any of the * 50 * above. * 51 * * 52 * o Executes a helper program, module, or script to do any of the above. * 53 * * 54 * This list is not exclusive, but is meant to clarify our interpretation * 55 * of derived works with some common examples. Other people may interpret * 56 * the plain GPL differently, so we consider this a special exception to * 57 * the GPL that we apply to Covered Software. Works which meet any of * 58 * these conditions must conform to all of the terms of this license, * 59 * particularly including the GPL Section 3 requirements of providing * 60 * source code and allowing free redistribution of the work as a whole. * 61 * * 62 * As another special exception to the GPL terms, the Nmap Project grants * 63 * permission to link the code of this program with any version of the * 64 * OpenSSL library which is distributed under a license identical to that * 65 * listed in the included docs/licenses/OpenSSL.txt file, and distribute * 66 * linked combinations including the two. * 67 * * 68 * The Nmap Project has permission to redistribute Npcap, a packet * 69 * capturing driver and library for the Microsoft Windows platform. * 70 * Npcap is a separate work with it's own license rather than this Nmap * 71 * license. Since the Npcap license does not permit redistribution * 72 * without special permission, our Nmap Windows binary packages which * 73 * contain Npcap may not be redistributed without special permission. * 74 * * 75 * Any redistribution of Covered Software, including any derived works, * 76 * must obey and carry forward all of the terms of this license, including * 77 * obeying all GPL rules and restrictions. For example, source code of * 78 * the whole work must be provided and free redistribution must be * 79 * allowed. All GPL references to "this License", are to be treated as * 80 * including the terms and conditions of this license text as well. * 81 * * 82 * Because this license imposes special exceptions to the GPL, Covered * 83 * Work may not be combined (even as part of a larger work) with plain GPL * 84 * software. The terms, conditions, and exceptions of this license must * 85 * be included as well. This license is incompatible with some other open * 86 * source licenses as well. In some cases we can relicense portions of * 87 * Nmap or grant special permissions to use it in other open source * 88 * software. Please contact fyodor@nmap.org with any such requests. * 89 * Similarly, we don't incorporate incompatible open source software into * 90 * Covered Software without special permission from the copyright holders. * 91 * * 92 * If you have any questions about the licensing restrictions on using * 93 * Nmap in other works, we are happy to help. As mentioned above, we also * 94 * offer an alternative license to integrate Nmap into proprietary * 95 * applications and appliances. These contracts have been sold to dozens * 96 * of software vendors, and generally include a perpetual license as well * 97 * as providing support and updates. They also fund the continued * 98 * development of Nmap. Please email sales@nmap.com for further * 99 * information. * 100 * * 101 * If you have received a written license agreement or contract for * 102 * Covered Software stating terms other than these, you may choose to use * 103 * and redistribute Covered Software under those terms instead of these. * 104 * * 105 * Source is provided to this software because we believe users have a * 106 * right to know exactly what a program is going to do before they run it. * 107 * This also allows you to audit the software for security holes. * 108 * * 109 * Source code also allows you to port Nmap to new platforms, fix bugs, * 110 * and add new features. You are highly encouraged to send your changes * 111 * to the dev@nmap.org mailing list for possible incorporation into the * 112 * main distribution. By sending these changes to Fyodor or one of the * 113 * Insecure.Org development mailing lists, or checking them into the Nmap * 114 * source code repository, it is understood (unless you specify * 115 * otherwise) that you are offering the Nmap Project the unlimited, * 116 * non-exclusive right to reuse, modify, and relicense the code. Nmap * 117 * will always be available Open Source, but this is important because * 118 * the inability to relicense code has caused devastating problems for * 119 * other Free Software projects (such as KDE and NASM). We also * 120 * occasionally relicense the code to third parties as discussed above. * 121 * If you wish to specify special license conditions of your * 122 * contributions, just say so when you send them. * 123 * * 124 * This program is distributed in the hope that it will be useful, but * 125 * WITHOUT ANY WARRANTY; without even the implied warranty of * 126 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the Nmap * 127 * license file for more details (it's in a COPYING file included with * 128 * Nmap, and also available from https://svn.nmap.org/nmap/COPYING) * 129 * * 130 ***************************************************************************/ 131 132 133 134 class Service; 135 136 /* 137 * Active connection taking place for authenticating service. 138 * Each connection may try to authenticatate more than once before closing, 139 * depending on the service. For UDP 1 connection = 1 authentication session. 140 */ 141 class Connection 142 { 143 public: 144 Connection(Service *serv); 145 ~Connection(); 146 147 int time_started; 148 int time_elapsed; 149 150 char *user; 151 char *pass; 152 153 /* 154 * True when we peer might close connection at the near moment. 155 * Consider the case, when some services after reaching the maximum 156 * authentication limit per connecton, just drop the connection without 157 * specifically telling you that you failed at the last authentication 158 * attempt. Thus, we use this, to be able to count the correct number of 159 * maximum attempts the peer lets us do (stored in 'supported_attempts' 160 * inside the Service class). A module should probably set it to true 161 * after writing the password on the wire and before issuing the next 162 * read call. Also if you use it, don't forget to set it to false, in the 163 * first state of your module, because we might need it to differentiate 164 * between normal server FINs and FINs/RSTs sent in the middle of an 165 * authentication due to strange network conditions. 166 */ 167 bool peer_might_close; 168 169 /* True if we have received a server reply, that indicated that it didn't 170 * close the connection prematurely. This may used in cases, when the 171 * server may close the connection after the maximum allowed auth attempts 172 * are reached, but will also print a relative message saying we failed. 173 */ 174 bool finished_normally; /* XXX not currently used anywhere */ 175 176 bool check_closed; /* true -> check if peer closed connection on us */ 177 bool peer_alive; /* true -> if peer is certain to be alive currently */ 178 bool auth_complete; /* true -> login pair tested */ 179 bool from_pool; /* true -> login pair was extracted from pair_pool */ 180 bool closed; /* true -> connection was closed */ 181 bool auth_success; /* true -> we found a valid pair!!! */ 182 bool force_close; /* true -> forcefully close the connection */ 183 184 void *misc_info; /* additional state information that might be needed */ 185 186 /* function pointer to module-specific free operation that deallocates 187 * all internal struct members of misc_info 188 */ 189 void (* ops_free)(Connection *); 190 191 int close_reason; 192 193 int state; /* module state-machine's current state */ 194 195 Buf *inbuf; /* buffer for inbound data */ 196 Buf *outbuf; /* buffer for outbound data */ 197 198 unsigned long login_attempts; /* login attempts up until now */ 199 nsock_iod niod; /* I/O descriptor for this connection */ 200 201 /* This stores our SSL session id, which will help speed up subsequent 202 * SSL connections. It's overwritten each time. void* is used so we don't 203 * need to #ifdef HAVE_OPENSSL all over. We'll cast later as needed. 204 */ 205 void *ssl_session; 206 207 Service *service; /* service it belongs to */ 208 }; 209 210 enum close_reasons { READ_EOF, READ_TIMEOUT, CON_ERR, CON_TIMEOUT, MODULE_ERR }; 211 212