Use the new API that nsock provides for proxychain parsing/handling.

NmapOps.cc

@@ -136,7 +136,7 @@ NmapOps::~NmapOps() {
     portlist = NULL;
   }
   if (proxy_chain) {
-    free(proxy_chain);
+    nsock_proxychain_delete(proxy_chain);
     proxy_chain = NULL;
   }
   if (exclude_spec) {

NmapOps.h

@@ -95,6 +95,7 @@
 #include "nmap.h"
 #include "global_structures.h"
 #include "output.h"
+#include <nsock.h>
 #include <string>
 
 class NmapOps {
@@ -340,7 +341,7 @@ class NmapOps {
   FILE *inputfd;
   char *portlist; /* Ports list specified by user */
 
-  char *proxy_chain;
+  nsock_proxychain proxy_chain;
 
 #ifndef NOLUA
   int script;

nmap.cc

@@ -935,7 +935,8 @@ void parse_options(int argc, char **argv) {
       } else if (optcmp(long_options[option_index].name, "nsock-engine") == 0) {
         nsock_set_default_engine(optarg);
       } else if (optcmp(long_options[option_index].name, "proxies") == 0) {
-        o.proxy_chain = strdup(optarg);
+        if (nsock_proxychain_new(optarg, &o.proxy_chain, NULL) < 0)
+          fatal("Invalid proxy chain specification");
       } else if (optcmp(long_options[option_index].name, "osscan-limit")  == 0) {
         o.osscan_limit = 1;
       } else if (optcmp(long_options[option_index].name, "osscan-guess")  == 0

service_scan.cc

@@ -2674,7 +2674,7 @@ int service_scan(std::vector<Target *> &Targets) {
   nsp_setdevice(nsp, o.device);
 
   if (o.proxy_chain) {
-    nsock_set_proxychain(nsp, o.proxy_chain);
+    nsp_set_proxychain(nsp, o.proxy_chain);
   }
 
 #if HAVE_OPENSSL