Nmap是一款非常强大的开源扫描工具。自己在使用过程中忍不住想仔细阅读一下它的源码。源码里面汇集了众多安全专家的精巧设计与优雅写法,读起来令人心旷神怡而又受益匪浅。
这里我们以阅读nmap6.0的代码作为主线来分析Nmap源码的实现框架。
源码下载地址:http://nmap.org/dist/nmap-6.01.tar.bz2
SVN检出:svn co https://svn.nmap.org/nmap
1 文件组织
我们先从总体上了解Nmap的文件组织方式及分析源码需要关注的重点。
1.1 目录结构
解压Nmap的源码包后,可以看到根目录下有许多的子目录和文件。
文件分析
放在Nmap/根目录下包括几种类型文件:
1) Nmap核心功能的源码(如nmap.cc/ scan_engine.cc/ service_scan.cc/osscan2.cc/ nse_main.lua等)。
2) Nmap的核心数据库文件(nmap-os-db/ nmap-service-probes/ nmap-rpc/nmap-protocols等)。
3) 编译链接相关的Makefile或CONFIG文件。
4) 其他杂项文件(如安装提示:README-WIN32)
目录分析
使用Windows的tree命令列举出Nmap的目录结构.
为了避免目录树过长,这里只显示了3个级别的目录,目录的主要作用在名字后面简略说明。
可以看到Nmap工具也使用到很多其他开源项目的成果,例如libdnet/ liblinear/ liblua/libpcap/ libpcre等;另外Nmap自身也实现很多有用的程序库,如nsock/ libnetutil/;Nmap项目包括附带几个小工具:1)ncat,这是根据TCPIP协议栈瑞士军刀netcat(该工具已停止维护更新)开发扩展出来的工具。2)nping,类似于Hping的工具,用于进行主机探测和发包收包。3)ndiff,用于比较两次nmap扫描结果之间差异。
Nmap/
├─docs(Nmap相关文档,包括License、usage说明及XMLschema文件等)
│ ├─licenses
│ └─man-xlate
├─libdnet-stripped(libdnet:简单的网络接口开源库)
│ ├─config
│ ├─include
│ └─src
├─liblinear(LIBLINEAR:负责大型线性分类的开源库)
│ └─blas
├─liblua(Lua脚本语言源码库)
├─libnetutil(Nmap实现的基本的网络实用函数)
├─libpcap(开源的抓包代码库libpcap)
│ ├─bpf
│ ├─ChmodBPF
│ ├─lbl
│ ├─missing
│ ├─msdos
│ ├─NMAP_MODIFICATIONS
│ ├─packaging
│ ├─pcap
│ ├─SUNOS4
│ ├─tests
│ └─Win32
├─libpcre(Perl兼容的正则表达式开源库libpcre)
├─macosx(该目录负责支持苹果的操作系统MACOS X)
│ └─nmap.pmdoc
├─mswin32(该目录负责支持Windows操作系统)
│ ├─lib
│ ├─license-format
│ ├─NET
│ ├─NETINET
│ ├─nsis
│ ├─OpenSSL
│ ├─pcap-include
│ ├─RPC
│ └─winpcap
├─nbase(Nmap封装的基础使用程序库,包括string/path/random等)
├─ncat(Ncat是Nmap项目组实现的新版的netcat:强大的网络工具)
│ ├─certs
│ ├─docs
│ └─test
├─ndiff(Ndiff是用于比较Nmap扫描结果的实用命令)
│ ├─docs
│ └─test-scans
├─nmap-update(负责Nmap更新相关操作)
├─nping(Nping是Nmap项目组实现的新版的Hping:网络探测与构建packet)
│ └─docs
├─nselib(Nmap使用Lua语言编写的常用的脚本库)
│ └─data
├─nsock(Nmap实现的并行的SocketEvent处理库)
│ ├─include
│ └─src
├─scripts(Nmap提供常用的扫描检查的lua脚本)
├─todo(介绍Nmap项目将来开发的具体任务)
└─zenmap(Nmap的官方的图形界面程序,由python语言编写)
├─install_scripts
├─radialnet
├─share
├─test
├─zenmapCore
└─zenmapGUI
1.2 文件类型
下面从源码类型的角度上浏览一下Nmap项目的特点:
Nmap6.0工程内总共包括1300多个文件。
1) C和C++文件有600多个,主要实现Nmap最核心的功能:主机发现、端口扫描、服务侦测、OS侦测及搭建脚本引擎框架;也包括其他开源项目如libpcap的源码。
2) Python文件有100多个,主要实现Zenmap图形界面,Zenmap会调用到Nmap基本命令,也实现一些新的功能:例如确定网络拓扑结构、Profile的管理(常用的命令保存为Profile)等。
3) Lua与NSE文件400多个,负责构建Nmap脚本引擎及提供常用的扫描脚本。其中NSE格式为Nmap定制的Lua文件,方便用户自行编写脚本进行功能扩展。
4) XML文件数十个,用于辅助描述Nmap的内容或Zenmap的测试等工作。
5) 其他文件,其他辅助工具操作的文件。
2 源码分析
2.1 执行流程框架
Nmap的执行流程简单清晰,主要的工作在nmap.cc文件中完成,而main.cc负责简单地包装nmap_main()函数。
nmap_main()函数是执行流程的核心。
准备阶段:在其中会执行参数解析、资源分配、基本扫描信息的输出、端口与地址列表的初始化、NSE环境准备及pre-scripts的运行等基本的准备操作。
工作阶段:然后进入主循环,每次循环对一组目标地址进行主机发现、端口扫描、服务与版本侦测、OS侦测及脚本扫描等操作,直到所有的目标地址都被扫描完毕才推出主循环。
善后阶段:在完成所有的扫描操作后,调用post-script完成相应处理,然后打印出扫描的最终结果,并释放掉分配的资源。
2.2 nmap_main()函数
以下代码是对nmap_main()函数基本的分析。
其中以///开头是新添加的注释。而以类似于///<Start------创建主机组状态,进入主循环--------Start>的形式出现的注释用于标注一个比较大的功能代码段。
Nmap的所有的功能都在此nmap_main()设有入口,以此为基础可以更深入地分析Nmap的其他模块。
int nmap_main(int argc, char *argv[]) {
int i;
vector<Target *> Targets;
time_t now;
struct hostent *target = NULL;
time_t timep;
char mytime[128];
addrset exclude_group;
#ifndef NOLUA
/* Only NSE scripts can add targets */
NewTargets *new_targets = NULL;///NewTargets为Singleton模式,产生单个实例
/* Pre-Scan and Post-Scan script results datastructure */
ScriptResults *script_scan_results = NULL;
#endif
char **host_exp_group;
int num_host_exp_groups;
HostGroupState *hstate = NULL;
unsigned int ideal_scan_group_sz = 0;
Target *currenths;
char *host_spec = NULL;
char myname[MAXHOSTNAMELEN + 1];
int sourceaddrwarning = 0; /* Have we warned them yet about unguessable
source addresses? */
unsigned int targetno;
char hostname[MAXHOSTNAMELEN + 1] = "";
struct sockaddr_storage ss;
size_t sslen;
char **fakeargv = NULL;
now = time(NULL);
local_time = localtime(&now);
///设置错误log输出函数
if(o.debugging)
nbase_set_log(fatal,error);
else
nbase_set_log(fatal,NULL);
if (argc < 2 ) printusage(-1);
/* argv faking silliness */
fakeargv = (char **) safe_malloc(sizeof(char *) * (argc + 1));
for(i=0; i < argc; i++) {
fakeargv[i] = strdup(argv[i]);
}
fakeargv[argc] = NULL;
Targets.reserve(100);
#ifdef WIN32
win_pre_init();
#endif
///调用parse_options进行命令参数的解析
parse_options(argc, fakeargv);
///在Linux下设置终端为只读非阻塞方式,在Windows平台为空函数。
tty_init(); // Put the keyboard in raw mode
///将解析命令时需要延迟执行的操作在此处处理
apply_delayed_options();
#ifdef WIN32
///调用WSAStartup启动Winsock DLL,后续网络解析等需要用到。
win_init();
#endif
///如果用户使用了参数--iflist,那么会在此处打印网卡和路由表信息,然后退出。
///该选项对于显示指定发送网卡非常有帮助,可以提供基本的网络设备信息。
if (delayed_options.iflist) {
print_iflist();
exit(0);
}
///quashargv部分用于修改命令行参数,将程序名字更改为FAKE_ARGV(默认为“pine”),
///并将剩余的各个参数都清空。
///在命令中加入-q可实现quashargv功能。这最初是为了逃避ps等程序名称显示,便于隐蔽Nmap。
///不过在Windows系统上并无实效。
/* more fakeargv junk, BTW malloc'ing extra space in argv[0] doesn't work */
if (o.quashargv) {
size_t fakeargvlen = strlen(FAKE_ARGV), argvlen = strlen(argv[0]);
if (argvlen < fakeargvlen)
fatal("If you want me to fake your argv, you need to call the program with a longer name. Try the full pathname, or rename it fyodorssuperdedouperportscanner");
strncpy(argv[0], FAKE_ARGV, fakeargvlen);
memset(&argv[0][fakeargvlen], '\0', strlen(&argv[0][fakeargvlen]));
for(i=1; i < argc; i++)
memset(argv[i], '\0', strlen(argv[i]));
}
///如果使用FTP bounce scan的扫描方式,那么需要首先保证该FTP网站是可以访问到的。
///关于FTP bounce scan更多介绍,请参考:http://nmap.org/nmap_doc.html#bounce
/* If he wants to bounce off of an FTP site, that site better damn well be reachable! */
if (o.bouncescan) {
if (!inet_pton(AF_INET, ftp.server_name, &ftp.server)) {
if ((target = gethostbyname(ftp.server_name)))
memcpy(&ftp.server, target->h_addr_list[0], 4);
else {
fatal("Failed to resolve FTP bounce proxy hostname/IP: %s",
ftp.server_name);
}
} else if (o.verbose) {
log_write(LOG_STDOUT, "Resolved FTP bounce attack proxy to %s (%s).\n",
ftp.server_name, inet_ntoa(ftp.server));
}
}
///<Start--------------扫描信息输出-----------------Start>
fflush(stdout);
fflush(stderr);
timep = time(NULL);
///准备将基本的扫描输出到文件与控制台中
/* Brief info in case they forget what was scanned */
Strncpy(mytime, ctime(&timep), sizeof(mytime));
chomp(mytime); ///去掉字符串末尾换行符
char *xslfname = o.XSLStyleSheet();///XML样式表
xml_start_document();
if (xslfname) {
xml_open_pi("xml-stylesheet");
xml_attribute("href", "%s", xslfname);
xml_attribute("type", "text/xsl");
xml_close_pi();
xml_newline();
}
std::string command;
if (argc > 0)
command += fakeargv[0];
for (i = 1; i < argc; i++) {
command += " ";
command += fakeargv[i];
}
xml_start_comment();
xml_write_escaped(" %s %s scan initiated %s as: %s ", NMAP_NAME, NMAP_VERSION, mytime, join_quoted(fakeargv, argc).c_str());
xml_end_comment();
xml_newline();
log_write(LOG_NORMAL|LOG_MACHINE, "# ");
log_write(LOG_NORMAL|LOG_MACHINE, "%s %s scan initiated %s as: ", NMAP_NAME, NMAP_VERSION, mytime);
log_write(LOG_NORMAL|LOG_MACHINE, "%s", command.c_str());
log_write(LOG_NORMAL|LOG_MACHINE, "\n");
xml_open_start_tag("nmaprun");
xml_attribute("scanner", "nmap");
xml_attribute("args", "%s", join_quoted(fakeargv, argc).c_str());
xml_attribute("start", "%lu", (unsigned long) timep);
xml_attribute("startstr", "%s", mytime);
xml_attribute("version", "%s", NMAP_VERSION);
xml_attribute("xmloutputversion", NMAP_XMLOUTPUTVERSION);
xml_close_start_tag();
xml_newline();
output_xml_scaninfo_records(&ports);
xml_open_start_tag("verbose");
xml_attribute("level", "%d", o.verbose);
xml_close_empty_tag();
xml_newline();
xml_open_start_tag("debugging");
xml_attribute("level", "%d", o.debugging);
xml_close_empty_tag();
xml_newline();
/* Before we randomize the ports scanned, lets output them to machine
parseable output */
if (o.verbose) ///输出机器可以解析端口信息(grepable格式)
output_ports_to_machine_parseable_output(&ports);
#if defined(HAVE_SIGNAL) && defined(SIGPIPE)
///注册信号处理函数,这里只是直接忽略SIGPIPE信号。其具体实现为#define SIG_IGN (void (*)(int))1
signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE so our program doesn't crash because
of it, but we really shouldn't get an unexpected
SIGPIPE */
#endif
///检查配置的最大并发度是否在系统最大的套接字数量范围之内
if (o.max_parallelism && (i = max_sd()) && i < o.max_parallelism) {
error("WARNING: Your specified max_parallel_sockets of %d, but your system says it might only give us %d. Trying anyway", o.max_parallelism, i);
}
if (o.debugging > 1) log_write(LOG_STDOUT, "The max # of sockets we are using is: %d\n", o.max_parallelism);
// At this point we should fully know our timing parameters
if (o.debugging) {
log_write(LOG_PLAIN, "--------------- Timing report ---------------\n");
log_write(LOG_PLAIN, " hostgroups: min %d, max %d\n", o.minHostGroupSz(), o.maxHostGroupSz());
log_write(LOG_PLAIN, " rtt-timeouts: init %d, min %d, max %d\n", o.initialRttTimeout(), o.minRttTimeout(), o.maxRttTimeout());
log_write(LOG_PLAIN, " max-scan-delay: TCP %d, UDP %d, SCTP %d\n", o.maxTCPScanDelay(), o.maxUDPScanDelay(), o.maxSCTPScanDelay());
log_write(LOG_PLAIN, " parallelism: min %d, max %d\n", o.min_parallelism, o.max_parallelism);
log_write(LOG_PLAIN, " max-retries: %d, host-timeout: %ld\n", o.getMaxRetransmissions(), o.host_timeout);
log_write(LOG_PLAIN, " min-rate: %g, max-rate: %g\n", o.min_packet_send_rate, o.max_packet_send_rate);
log_write(LOG_PLAIN, "---------------------------------------------\n");
}
///<End--------------扫描信息输出-----------------End>
///<Start-------------端口与地址初始化-------------Start>
/* Before we randomize the ports scanned, we must initialize PortList class. */
if (o.ipprotscan)
PortList::initializePortMap(IPPROTO_IP, ports.prots, ports.prot_count);
if (o.TCPScan())
PortList::initializePortMap(IPPROTO_TCP, ports.tcp_ports, ports.tcp_count);
if (o.UDPScan())
PortList::initializePortMap(IPPROTO_UDP, ports.udp_ports, ports.udp_count);
if (o.SCTPScan())
PortList::initializePortMap(IPPROTO_SCTP, ports.sctp_ports, ports.sctp_count);
if (o.randomize_ports) {
if (ports.tcp_count) {
///将端口进行随机打乱操作
shortfry(ports.tcp_ports, ports.tcp_count);
// move a few more common ports closer to the beginning to speed scan
///将常见的端口移动到前面,以便最快地发现有效的端口
random_port_cheat(ports.tcp_ports, ports.tcp_count);
}
if (ports.udp_count)
shortfry(ports.udp_ports, ports.udp_count);
if (ports.sctp_count)
shortfry(ports.sctp_ports, ports.sctp_count);
if (ports.prot_count)
shortfry(ports.prots, ports.prot_count);
}
///exclude_group记录的是排除地址,如命令行nmap 192.168.1.1/24 --exclude 192.168.1.0-10
///扫描C类地址192.168.1.x,并排除其中192.168.1.0-192.168.1.10地址。
///addrset_init()将初始化排除地址组的链表头指针为NULL。
addrset_init(&exclude_group);
/* lets load our exclude list */
if (o.excludefd != NULL) {///文件指定的排除地址
load_exclude_file(&exclude_group, o.excludefd);
fclose(o.excludefd);
}
if (o.exclude_spec != NULL) {///命令行直接指定的排除地址
load_exclude_string(&exclude_group, o.exclude_spec);
}
if (o.debugging > 3) ///若调试级别大于3,打印出排除地址信息
dumpExclude(&exclude_group);
///<End-------------端口与地址初始化-------------End>
///<Start------NSE环境准备并执行pre-scripts--------Start>
#ifndef NOLUA
if (o.scriptupdatedb) {
o.max_ips_to_scan = o.numhosts_scanned; // disable warnings?
}
if (o.servicescan) ///当配置了版本扫描时,会默认启动版本扫描脚本,位于NSE中version类别中
o.scriptversion = 1;
if (o.scriptversion || o.script || o.scriptupdatedb)
open_nse(); ///开启NSE环境
/* Run the script pre-scanning phase */
if (o.script) {
new_targets = NewTargets::get(); ///分配实例或返回已有实例(Singleton模式)
script_scan_results = get_script_scan_results_obj();
script_scan(Targets, SCRIPT_PRE_SCAN);
printscriptresults(script_scan_results, SCRIPT_PRE_SCAN);
script_scan_results->clear();
}
#endif
///<End------NSE环境准备并执行pre-scripts--------End>
///<Start------创建主机组状态,进入主循环--------Start>
/* Time to create a hostgroup state object filled with all the requested
machines. The list is initially empty. It is refilled inside the loop
whenever it is empty. */
///分配字符串数组,用以保存各个主机表达式字符串的地址
host_exp_group = (char **) safe_malloc(o.ping_group_sz * sizeof(char *));
num_host_exp_groups = 0;
hstate = new HostGroupState(o.ping_group_sz, o.randomize_hosts,
host_exp_group, num_host_exp_groups);
do {
///确定最佳的host group的大小,该大小取决于扫描方式与网络速度。
ideal_scan_group_sz = determineScanGroupSize(o.numhosts_scanned, &ports);
///<Start---------对host group进行主机发现----------Start>
///以下的while()将依次进行主机发现,确定主机是否在线。
///若该主机在线加入该host group,用于后续的操作。当数量达到最佳大小时,退出循环。
while(Targets.size() < ideal_scan_group_sz) {
o.current_scantype = HOST_DISCOVERY; ///设置扫描状态:HOST_DICOVERY
currenths = nexthost(hstate, &exclude_group, &ports, o.pingtype); ///主机发现的核心函数
///如果当前主机发现无法找到有效主机,那么会做以下尝试:
///1)更换主机表达式(host expressions)
///例如:nmap 192.168.1.1/24 10.10.30.55-100,192.168.1.x不能再发现主机时候,切换为10.30.55-100
///2)将执行脚本扫描时发现的主机,加入主机表达式组host_exp_group
///3) 建立新的主机组状态,并做最后的主机发现尝试
if (!currenths) {
/* Try to refill with any remaining expressions */
/* First free the old ones */
for(i=0; i < num_host_exp_groups; i++)
free(host_exp_group[i]);
num_host_exp_groups = 0;
/* Now grab any new expressions */
while(num_host_exp_groups < o.ping_group_sz &&
(!o.max_ips_to_scan || o.max_ips_to_scan > o.numhosts_scanned + (int) Targets.size() + num_host_exp_groups) &&
(host_spec = grab_next_host_spec(o.inputfd, o.generate_random_ips, argc, fakeargv))) {
// For purposes of random scan
host_exp_group[num_host_exp_groups++] = strdup(host_spec);
}
#ifndef NOLUA
/* Add the new NSE discovered targets to the scan queue */
if (o.script) {
if (new_targets != NULL) {
while (new_targets->get_queued() > 0 && num_host_exp_groups < o.ping_group_sz) {
std::string target_spec = new_targets->read();
if (target_spec.length())
host_exp_group[num_host_exp_groups++] = strdup(target_spec.c_str());
}
if (o.debugging > 3)
log_write(LOG_PLAIN,
"New targets in the scanned cache: %ld, pending ones: %ld.\n",
new_targets->get_scanned(), new_targets->get_queued());
}
}
#endif
if (num_host_exp_groups == 0) ///当没有其他的主机表达式时,退出整个主机发现循环
break;
delete hstate;
hstate = new HostGroupState(o.ping_group_sz, o.randomize_hosts,host_exp_group,
num_host_exp_groups);
/* Try one last time -- with new expressions */
currenths = nexthost(hstate, &exclude_group, &ports, o.pingtype);
if (!currenths)
break;
}
if (currenths->flags & HOST_UP && !o.listscan)
o.numhosts_up++;
if ((o.noportscan && !o.traceroute
#ifndef NOLUA
&& !o.script
#endif
) || o.listscan) {
///当不进行端口扫描(-sn)并且没有指定traceroute和脚本的话,那么扫描就到此处就结束。
///或当进行列表扫描(-sL,只列举出主机IP,并不真正扫描)时,扫描也到此结束。
/* We're done with the hosts */
if (currenths->flags & HOST_UP || o.verbose) {
xml_start_tag("host");
write_host_header(currenths);
printmacinfo(currenths);
// if (currenths->flags & HOST_UP)
// log_write(LOG_PLAIN,"\n");
printtimes(currenths);
xml_end_tag();
xml_newline();
log_flush_all();
}
delete currenths;
o.numhosts_scanned++;
continue;
}
///若配置要伪造源IP地址(-S ip),将命令行中传入的地址写入当前主机源地址
if (o.spoofsource) {
o.SourceSockAddr(&ss, &sslen);
currenths->setSourceSockAddr(&ss, sslen);
}
///如果主机状态为HOST_DOWN,那么需要根据配置考虑是否输出其状态
///输出条件:verbose级别大于0,并且没有指定openonly或已确定有开放端口。
///疑问:如果有open Ports,为什么此主机状态会是HOST_DOWN呢?
/* I used to check that !currenths->weird_responses, but in some
rare cases, such IPs CAN be port successfully scanned and even
connected to */
if (!(currenths->flags & HOST_UP)) {
if (o.verbose && (!o.openOnly() || currenths->ports.hasOpenPorts())) {
xml_start_tag("host");
write_host_header(currenths);
xml_end_tag();
xml_newline();
}
delete currenths;
o.numhosts_scanned++;
continue;
}
///如果是RawScan(即涉及到构建原始的packet的扫描方式,如SYN/FIN/ARP等等),
///需要设置套接字源IP地址
if (o.RawScan()) {
if (currenths->SourceSockAddr(NULL, NULL) != 0) {
if (o.SourceSockAddr(&ss, &sslen) == 0) {
///若全局变量o中已有源IP地址,直接赋值给当前目标机
currenths->setSourceSockAddr(&ss, sslen);
} else {
///否则,需要重新查询、解析主机来获取源地址
if (gethostname(myname, MAXHOSTNAMELEN) ||
resolve(myname, 0, 0, &ss, &sslen, o.af()) == 0)
fatal("Cannot get hostname! Try using -S <my_IP_address> or -e <interface to scan through>\n");
o.setSourceSockAddr(&ss, sslen);
currenths->setSourceSockAddr(&ss, sslen);
if (! sourceaddrwarning) {
error("WARNING: We could not determine for sure which interface to use, so we are guessing %s . If this is wrong, use -S <my_IP_address>.",
inet_socktop(&ss));
sourceaddrwarning = 1;
}
}
}
if (!currenths->deviceName())///网卡名字,在主机发现函数nexthost()中设置
fatal("Do not have appropriate device name for target");
///如果新发现的主机与该主机组类型不大相同,那么考虑将此主机放入新的主机组内。
///因为对主机分组是为了加快扫描速度,所以尽可能特征相似的主机组合在一起。
///流水线工作模式的扫描思想。
/* Hosts in a group need to be somewhat homogeneous. Put this host in
the next group if necessary. See target_needs_new_hostgroup for the
details of when we need to split. */
if (target_needs_new_hostgroup(Targets, currenths)) {
returnhost(hstate);
o.numhosts_up--;
break;
}
///设置IP诱骗时,将当前主机真实IP放入decoyturn位置。
///其他的诱骗IP地址在parse options时已经确定。
o.decoys[o.decoyturn] = currenths->v4source();
}
///将新发现的主机加入Targets向量
Targets.push_back(currenths);
}///一次分组的主机发现在此处结束,接下来执行端口扫描、服务侦测、OS侦测、脚本扫描等。
///<End---------对host group进行主机发现----------End>
if (Targets.size() == 0)///主机发现没有找到任何目标机时,退出主循环
break; /* Couldn't find any more targets */
// Set the variable for status printing
o.numhosts_scanning = Targets.size();
// Our source must be set in decoy list because nexthost() call can
// change it (that issue really should be fixed when possible)
if (o.af() == AF_INET && o.RawScan())
o.decoys[o.decoyturn] = Targets[0]->v4source();
/* I now have the group for scanning in the Targets vector */
if (!o.noportscan) {
///<Start---------端口扫描----------Start>
///针对用户指定的不同扫描方式,分别使用不同参数调用ultra_scan()
///ultra_scan()设计精巧,用统一的接口处理大多数的端口扫描
// Ultra_scan sets o.scantype for us so we don't have to worry
if (o.synscan)
ultra_scan(Targets, &ports, SYN_SCAN);
if (o.ackscan)
ultra_scan(Targets, &ports, ACK_SCAN);
if (o.windowscan)
ultra_scan(Targets, &ports, WINDOW_SCAN);
if (o.finscan)
ultra_scan(Targets, &ports, FIN_SCAN);
if (o.xmasscan)
ultra_scan(Targets, &ports, XMAS_SCAN);
if (o.nullscan)
ultra_scan(Targets, &ports, NULL_SCAN);
if (o.maimonscan)
ultra_scan(Targets, &ports, MAIMON_SCAN);
if (o.udpscan)
ultra_scan(Targets, &ports, UDP_SCAN);
if (o.connectscan)
ultra_scan(Targets, &ports, CONNECT_SCAN);
if (o.sctpinitscan)
ultra_scan(Targets, &ports, SCTP_INIT_SCAN);
if (o.sctpcookieechoscan)
ultra_scan(Targets, &ports, SCTP_COOKIE_ECHO_SCAN);
if (o.ipprotscan)
ultra_scan(Targets, &ports, IPPROT_SCAN);
/* These lame functions can only handle one target at a time */
if (o.idlescan) {
for(targetno = 0; targetno < Targets.size(); targetno++) {
o.current_scantype = IDLE_SCAN;
keyWasPressed(); // Check if a status message should be printed
idle_scan(Targets[targetno], ports.tcp_ports,
ports.tcp_count, o.idleProxy, &ports);
}
}
if (o.bouncescan) {
for(targetno = 0; targetno < Targets.size(); targetno++) {
o.current_scantype = BOUNCE_SCAN;
keyWasPressed(); // Check if a status message should be printed
if (ftp.sd <= 0) ftp_anon_connect(&ftp);
if (ftp.sd > 0) bounce_scan(Targets[targetno], ports.tcp_ports,
ports.tcp_count, &ftp);
}
}
///<End---------端口扫描----------End>
///<Start------服务与版本扫描--------Start>
if (o.servicescan) {
o.current_scantype = SERVICE_SCAN;
service_scan(Targets);
}
if (o.servicescan) {
/* This scantype must be after any TCP or UDP scans since it
* get's it's port scan list from the open port list of the current
* host rather than port list the user specified.
*/
for(targetno = 0; targetno < Targets.size(); targetno++)
pos_scan(Targets[targetno], NULL, 0, RPC_SCAN);
}
///<End------服务与版本扫描--------End>
}
///操作系统扫描
if (o.osscan){
OSScan os_engine;
os_engine.os_scan(Targets);
}
///若需要路径追踪,在此处调用traceroute获取路径
if (o.traceroute)
traceroute(Targets);
///脚本扫描
#ifndef NOLUA
if(o.script || o.scriptversion) {
script_scan(Targets, SCRIPT_SCAN);
}
#endif
///<Start------输出扫描结果--------Start>
for(targetno = 0; targetno < Targets.size(); targetno++) {
currenths = Targets[targetno];
/* Now I can do the output and such for each host */
if (currenths->timedOut(NULL)) {
xml_open_start_tag("host");
xml_attribute("starttime", "%lu", (unsigned long) currenths->StartTime());
xml_attribute("endtime", "%lu", (unsigned long) currenths->EndTime());
xml_close_start_tag();
write_host_header(currenths);
xml_end_tag(); /* host */
xml_newline();
log_write(LOG_PLAIN,"Skipping host %s due to host timeout\n",
currenths->NameIP(hostname, sizeof(hostname)));
log_write(LOG_MACHINE,"Host: %s (%s)\tStatus: Timeout",
currenths->targetipstr(), currenths->HostName());
} else {
/* --open means don't show any hosts without open ports. */
if (o.openOnly() && !currenths->ports.hasOpenPorts())
continue;
xml_open_start_tag("host");
xml_attribute("starttime", "%lu", (unsigned long) currenths->StartTime());
xml_attribute("endtime", "%lu", (unsigned long) currenths->EndTime());
xml_close_start_tag();
write_host_header(currenths);
printportoutput(currenths, ¤ths->ports);
printmacinfo(currenths);
printosscanoutput(currenths);
printserviceinfooutput(currenths);
#ifndef NOLUA
printhostscriptresults(currenths);
#endif
if (o.traceroute)
printtraceroute(currenths);
printtimes(currenths);
log_write(LOG_PLAIN|LOG_MACHINE,"\n");
xml_end_tag(); /* host */
xml_newline();
}
}
log_flush_all();
///<End------输出扫描结果--------End>
o.numhosts_scanned += Targets.size();
/* Free all of the Targets */
while(!Targets.empty()) {
currenths = Targets.back();
delete currenths;
Targets.pop_back();
}
o.numhosts_scanning = 0;
} while(!o.max_ips_to_scan || o.max_ips_to_scan > o.numhosts_scanned);
///当指定的扫描数量没有达到已经扫描数量,继续循环
///<End------创建主机组状态,进入主循环--------End>
///执行post-script,释放分配的资源
#ifndef NOLUA
if (o.script) {
script_scan(Targets, SCRIPT_POST_SCAN);
printscriptresults(script_scan_results, SCRIPT_POST_SCAN);
script_scan_results->clear();
delete new_targets;
new_targets = NULL;
}
#endif
delete hstate;
addrset_free(&exclude_group);
hstate = NULL;
/* Free host expressions */
for(i=0; i < num_host_exp_groups; i++)
free(host_exp_group[i]);
num_host_exp_groups = 0;
free(host_exp_group);
if (o.inputfd != NULL)
fclose(o.inputfd);
printdatafilepaths();
printfinaloutput();
free_scan_lists(&ports);
eth_close_cached();
if (o.release_memory) {
/* Free fake argv */
for(i=0; i < argc; i++)
free(fakeargv[i]);
free(fakeargv);
nmap_free_mem();
}
return 0;
}