/*************************************************************************** * services.cc -- Various functions relating to reading the nmap-services * * file and port <-> service mapping * * * ***********************IMPORTANT NMAP LICENSE TERMS************************ * * * The Nmap Security Scanner is (C) 1996-2008 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 just meant to * * clarify our interpretation of derived works with some common examples. * * These restrictions only apply when you actually redistribute Nmap. For * * example, nothing stops you from writing and selling a proprietary * * front-end to Nmap. Just distribute it by itself, and point people to * * http://nmap.org to download Nmap. * * * * We don't consider these to be added restrictions on top of the GPL, but * * just a clarification of how we interpret "derived works" as it applies * * to our GPL-licensed Nmap product. This is similar to the way Linus * * Torvalds has announced his interpretation of how "derived works" * * applies to Linux kernel modules. Our interpretation refers only to * * Nmap - we don't speak for any other GPL products. * * * * 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 COPYING.OpenSSL file, and distribute linked * * combinations including the two. You must obey the GNU GPL in all * * respects for all of the code used other than OpenSSL. If you modify * * this file, you may extend this exception to your version of the file, * * but you are not obligated to do so. * * * * If you received these files with a written license agreement or * * contract stating terms other than the terms above, then that * * alternative license agreement takes precedence over these comments. * * * * 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 (none * * have been found so far). * * * * 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 fyodor@insecure.org for possible incorporation into the main * * distribution. By sending these changes to Fyodor or one of the * * Insecure.Org development mailing lists, it is assumed that you are * * offering Fyodor and 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. * * * ***************************************************************************/ /* $Id$ */ #include "services.h" #include "NmapOps.h" #include "charpool.h" #include "nmap_error.h" #include "utils.h" extern NmapOps o; static int numtcpports = 0; static int numudpports = 0; static struct service_list *service_table[SERVICE_TABLE_SIZE]; static struct service_list *sorted_services = NULL; static int services_initialized = 0; static int ratio_format = 0; // 0 = /etc/services no-ratio format. 1 = new nmap format static int nmap_services_init() { if (services_initialized) return 0; char filename[512]; FILE *fp; char servicename[128], proto[16]; u16 portno; char *p; char line[1024]; int lineno = 0; struct service_list *current, *previous, *sp; int res; double ratio; int ratio_n, ratio_d; if (nmap_fetchfile(filename, sizeof(filename), "nmap-services") != 1) { #ifndef WIN32 error("Unable to find nmap-services! Resorting to /etc/services"); strcpy(filename, "/etc/services"); #else int len, wnt = GetVersion() < 0x80000000; error("Unable to find nmap-services! Resorting to /etc/services"); if(wnt) len = GetSystemDirectory(filename, 480); // be safe else len = GetWindowsDirectory(filename, 480); // be safe if(!len) error("Get%sDirectory failed (%d) @#!#@", wnt ? "System" : "Windows", GetLastError()); else { if(wnt) strcpy(filename + len, "\\drivers\\etc\\services"); else strcpy(filename + len, "\\services"); } #endif } fp = fopen(filename, "r"); if (!fp) { fatal("Unable to open %s for reading service information", filename); } /* Record where this data file was found. */ o.loaded_data_files["nmap-services"] = filename; memset(service_table, 0, sizeof(service_table)); while(fgets(line, sizeof(line), fp)) { lineno++; p = line; while(*p && isspace((int) *p)) p++; if (*p == '#') continue; res = sscanf(line, "%127s %hu/%15s %d/%d", servicename, &portno, proto, &ratio_n, &ratio_d); if (res == 3) { ratio = 0; } else if (res == 5) { if (ratio_n < 0 || ratio_d < 0) fatal("%s:%d contains an invalid negative value", filename, lineno); if (ratio_n > ratio_d) fatal("%s:%d has a ratio %g. All ratios must be < 1", filename, lineno, (double)ratio_n/ratio_d); if (ratio_d == 0) fatal("%s:%d has a ratio denominator of 0 causing a division by 0 error", filename, lineno); ratio = (double)ratio_n / ratio_d; ratio_format = 1; } else { continue; } portno = htons(portno); /* Now we make sure our service table doesn't have duplicates */ for(current = service_table[portno % SERVICE_TABLE_SIZE], previous = NULL; current; current = current->next) { if (portno == (u16) current->servent->s_port && strcasecmp(proto, current->servent->s_proto) == 0) { if (o.debugging) { error("Port %d proto %s is duplicated in services file %s", ntohs(portno), proto, filename); } break; } previous = current; } /* Current service in the file was a duplicate, get another one */ if (current) continue; if (strncasecmp(proto, "tcp", 3) == 0) { numtcpports++; } else if (strncasecmp(proto, "udp", 3) == 0) { numudpports++; } else if (strncasecmp(proto, "ddp", 3) == 0) { /* ddp is some apple thing...we don't "do" that */ } else if (strncasecmp(proto, "divert", 6) == 0) { /* divert sockets are for freebsd's natd */ } else if (strncasecmp(proto, "#", 1) == 0) { /* possibly misplaced comment, but who cares? */ } else { if (o.debugging) error("Unknown protocol (%s) on line %d of services file %s.", proto, lineno, filename); continue; } current = (struct service_list *) cp_alloc(sizeof(struct service_list)); current->servent = (struct servent *) cp_alloc(sizeof(struct servent)); current->ratio = ratio; current->next = NULL; if (previous == NULL) { service_table[portno % SERVICE_TABLE_SIZE] = current; } else { previous->next = current; } current->servent->s_name = cp_strdup(servicename); current->servent->s_port = portno; current->servent->s_proto = cp_strdup(proto); current->servent->s_aliases = NULL; sp = (struct service_list *) cp_alloc(sizeof(struct service_list)); sp->servent = current->servent; sp->ratio = current->ratio; sp->next = NULL; if (sorted_services == NULL || sorted_services->ratio < sp->ratio) { sp->next = sorted_services; sorted_services = sp; } else for (current=sorted_services;;current=current->next) { if (current->next == NULL) { current->next = sp; break; } else if (current->next->ratio < sp->ratio) { sp->next = current->next; current->next = sp; break; } } } fclose(fp); services_initialized = 1; return 0; } /* Adds ports whose names match mask and one or more protocols * specified by range_type to porttbl. Increases the respective * protocol counts in ports. * Returns the number of ports added in total. */ int addportsfromservmask(char *mask, u8 *porttbl, int range_type) { struct service_list *current; int bucket,t=0; if (!services_initialized && nmap_services_init() == -1) fatal("%s: Couldn't get port numbers", __func__); for(bucket = 0; bucket < SERVICE_TABLE_SIZE; bucket++) { for(current = service_table[bucket % SERVICE_TABLE_SIZE]; current; current = current->next) { if (wildtest(mask, current->servent->s_name)) { if ((range_type & SCAN_TCP_PORT) && strcmp(current->servent->s_proto, "tcp") == 0) { porttbl[ntohs(current->servent->s_port)] |= SCAN_TCP_PORT; t++; } if ((range_type & SCAN_UDP_PORT) && strcmp(current->servent->s_proto, "udp") == 0) { porttbl[ntohs(current->servent->s_port)] |= SCAN_UDP_PORT; t++; } } } } return t; } struct servent *nmap_getservbyport(int port, const char *proto) { struct service_list *current; if (nmap_services_init() == -1) return NULL; for(current = service_table[port % SERVICE_TABLE_SIZE]; current; current = current->next) { if (((u16) port == (u16) current->servent->s_port) && strcmp(proto, current->servent->s_proto) == 0) return current->servent; } /* Couldn't find it ... oh well. */ return NULL; } static int port_compare(const void *a, const void *b) { unsigned short ua = *((unsigned short *) a), ub = *((unsigned short *) b); if (ua > ub) return 1; else return -1; } // is_port_member() returns true if serv is an element of ptsdata. // This could be implemented MUCH more efficiently but it should only be // called when you use a non-default top-ports or port-ratio value TOGETHER WITH // a -p portlist. static int is_port_member(struct scan_lists *ptsdata, struct service_list *serv) { int i; if (serv->servent->s_proto[0] == 't') { for (i=0; itcp_count; i++) if (ntohs(serv->servent->s_port) == ptsdata->tcp_ports[i]) return 1; } else { for (i=0; iudp_count; i++) if (ntohs(serv->servent->s_port) == ptsdata->udp_ports[i]) return 1; } return 0; } // gettoppts() sets its third parameter, a scan_list, with the most // common ports scanned by Nmap according to the ratios specified in // the nmap-services file. // // If level is below 1.0 then we treat it as a minimum ratio and we // add all ports with ratios above level. // // If level is 1 or above, we treat it as a "top ports" directive // and return the N highest ratio ports (where N==level). // // This function doesn't support IP protocol scan so only call this // function if o.TCPScan() || o.UDPScan() void gettoppts(double level, char *portlist, struct scan_lists * ports) { int ti=0, ui=0; struct scan_lists ptsdata = { 0 }; bool ptsdata_initialized = false; struct service_list *current; if (!services_initialized && nmap_services_init() == -1) fatal("%s: Couldn't get port numbers", __func__); if (ratio_format == 0) { if (level != -1) fatal("Unable to use --top-ports or --port-ratio with an old style (no-ratio) services file"); if (portlist){ getpts(portlist, ports); return; }else if (o.fastscan){ getpts("[-]", ports); return; }else{ getpts("1-1024,[1025-]", ports); return; } } // TOP PORT DEFAULTS if (level == -1) { if (portlist){ getpts(portlist, ports); return; } if (o.fastscan) level = 100; else level = 0.01; } if (portlist){ getpts(portlist, &ptsdata); ptsdata_initialized = true; } if (level < 1) { for (current=sorted_services; current; current=current->next) { if (ptsdata_initialized && !is_port_member(&ptsdata, current)) continue; if (current->ratio >= level) { if (o.TCPScan() && current->servent->s_proto[0] == 't') ports->tcp_count++; else if (o.UDPScan() && current->servent->s_proto[0] == 'u') ports->udp_count++; } else break; } if (ports->tcp_count) ports->tcp_ports = (unsigned short *)safe_zalloc(ports->tcp_count * sizeof(unsigned short)); if (ports->udp_count) ports->udp_ports = (unsigned short *)safe_zalloc(ports->udp_count * sizeof(unsigned short)); ports->prots = NULL; for (current=sorted_services;current;current=current->next) { if (ptsdata_initialized && !is_port_member(&ptsdata, current)) continue; if (current->ratio >= level) { if (o.TCPScan() && current->servent->s_proto[0] == 't') ports->tcp_ports[ti++] = ntohs(current->servent->s_port); else if (o.UDPScan() && current->servent->s_proto[0] == 'u') ports->udp_ports[ui++] = ntohs(current->servent->s_port); } else break; } } else if (level >= 1) { if (level > 65536) fatal("Level argument to gettoppts (%g) is too large", level); if (o.TCPScan()) { ports->tcp_count = MIN((int) level, numtcpports); ports->tcp_ports = (unsigned short *)safe_zalloc(ports->tcp_count * sizeof(unsigned short)); } if (o.UDPScan()) { ports->udp_count = MIN((int) level, numudpports); ports->udp_ports = (unsigned short *)safe_zalloc(ports->udp_count * sizeof(unsigned short)); } ports->prots = NULL; for (current=sorted_services;current && (ti < ports->tcp_count || ui < ports->udp_count);current=current->next) { if (ptsdata_initialized && !is_port_member(&ptsdata, current)) continue; if (o.TCPScan() && current->servent->s_proto[0] == 't' && ti < ports->tcp_count) ports->tcp_ports[ti++] = ntohs(current->servent->s_port); else if (o.UDPScan() && current->servent->s_proto[0] == 'u' && ui < ports->udp_count) ports->udp_ports[ui++] = ntohs(current->servent->s_port); } if (ti < ports->tcp_count) ports->tcp_count = ti; if (ui < ports->udp_count) ports->udp_count = ui; } else fatal("Argument to gettoppts (%g) should be a positive ratio below 1 or an integer of 1 or higher", level); if (ptsdata_initialized) { free_scan_lists(&ptsdata); ptsdata_initialized = false; } if (ports->tcp_count > 1) qsort(ports->tcp_ports, ports->tcp_count, sizeof(unsigned short), &port_compare); if (ports->udp_count > 1) qsort(ports->udp_ports, ports->udp_count, sizeof(unsigned short), &port_compare); if (o.debugging && level < 1) log_write(LOG_STDOUT, "PORTS: Using ports open on %g%% or more average hosts (TCP:%d, UDP:%d)\n", level*100, ports->tcp_count, ports->udp_count); else if (o.debugging && level >= 1) log_write(LOG_STDOUT, "PORTS: Using top %d ports found open (TCP:%d, UDP:%d)\n", (int) level, ports->tcp_count, ports->udp_count); }