- http_apache steg with updated stegmods successfully tested.

- PNGSteg module has migrated to to use vector<uint_8> buffers, activated and tested.
- file extensions now are specified in the related steg modules.
- content-length header is added to HTTP response in case it is missing.
- PayloadScraper migrated to use a map to store the steg modules.
- dead code snippet related to generating HTTP response headers removed.
- has_eligible_HTTP_content mode to trace_payload_server.

Makefile.am

@@ -36,11 +36,11 @@ STEGANOGRAPHERS = \
 	src/steg/trace_payload_server.cc \
 	src/steg/payload_scraper.cc \
 	src/steg/apache_payload_server.cc \
-	src/steg/http_steg_mods/htmlSteg.cc 
+	src/steg/http_steg_mods/htmlSteg.cc \ 
+	src/steg/http_steg_mods/pngSteg.cc 
+# 	src/steg/http_steg_mods/gifSteg.cc 
 # 	src/steg/http_steg_mods/pdfSteg.cc 
 # 	src/steg/http_steg_mods/swfSteg.cc 
-# 	src/steg/http_steg_mods/pngSteg.cc 
-# 	src/steg/http_steg_mods/gifSteg.cc 
 
 libstegotorus_a_SOURCES = \
 	src/base64.cc \

conf.d/chop-http-apache-server.yaml

@@ -19,4 +19,5 @@ protocols:
     stegs:
       - name: "http_apache"
         down-address: 127.0.0.1:5000
-        cover-list: "apache_payload/funnycatpix.csv"
+        cover-list: "apache_payload/cover_list_puppiesden.csv"
+#        cover-list: "apache_payload/funnycatpix.csv"

src/steg/apache_payload_server.cc

@@ -8,9 +8,6 @@
 #include "crypt.h"
 #include "rng.h"
 #include "apache_payload_server.h"
-
-#include "http_steg_mods/file_steg.h"
-#include "http_steg_mods/jpgSteg.h"
 #include "payload_scraper.h"
 
 using namespace std;
@@ -52,7 +49,7 @@ ApachePayloadServer::ApachePayloadServer(MachineSide init_side, const string& da
         log_debug("payload database does not exists.");
         log_debug("scarping payloads to create the database...");
 
-        PayloadScraper my_scraper(_database_filename, _apache_host_name,  cover_list);
+        PayloadScraper my_scraper(_database_filename, _apache_host_name, cover_list);
         my_scraper.scrape();
 
       }

src/steg/http.cc

@@ -28,12 +28,12 @@ using namespace std;
 #include "b64cookies.h"
 
 #include "http_steg_mods/file_steg.h"
-// #include "http_steg_mods/swfSteg.h"
-// #include "http_steg_mods/pdfSteg.h"
 #include "http_steg_mods/jsSteg.h"
 #include "http_steg_mods/jpgSteg.h"
-// #include "http_steg_mods/pngSteg.h"
+#include "http_steg_mods/pngSteg.h"
 // #include "http_steg_mods/gifSteg.h"
+// #include "http_steg_mods/swfSteg.h"
+// #include "http_steg_mods/pdfSteg.h"
 #include "http_steg_mods/htmlSteg.h"
 
 #include "http.h"
@@ -154,16 +154,22 @@ http_steg_config_t::init_file_steg_mods()
   //if the steg_mod option has set by the user, only those steg mods
   //will be activated otherwise, all other steg mods will be activated
 
+  file_steg_mods[HTTP_CONTENT_JPEG] = new JPGSteg(*payload_server, noise2signal);
+  file_steg_mods[HTTP_CONTENT_PNG] = new PNGSteg(*payload_server, noise2signal);
+  file_steg_mods[HTTP_CONTENT_JAVASCRIPT] = new JSSteg(*payload_server, noise2signal);
+  file_steg_mods[HTTP_CONTENT_HTML] = new HTMLSteg(*payload_server, noise2signal);
   //TODO:: re-enable when all other Steg mods are migrated to vector<uint_16>
   //coverpayload model.
-  file_steg_mods[HTTP_CONTENT_JPEG] = new JPGSteg(*payload_server, noise2signal);
-  // file_steg_mods[HTTP_CONTENT_PNG] = new PNGSteg(*payload_server, noise2signal);
   // file_steg_mods[HTTP_CONTENT_GIF] = new GIFSteg(*payload_server, noise2signal);
   // file_steg_mods[HTTP_CONTENT_SWF] = new SWFSteg(*payload_server, noise2signal);
   // file_steg_mods[HTTP_CONTENT_PDF] = new PDFSteg(*payload_server, noise2signal);
-  file_steg_mods[HTTP_CONTENT_JAVASCRIPT] = new JSSteg(*payload_server, noise2signal);
-  file_steg_mods[HTTP_CONTENT_HTML] = new HTMLSteg(*payload_server, noise2signal);
 
+  //initiate the supported extension list
+
+  for(auto cur_steg_mod : file_steg_mods)
+    for(auto cur_supported_extension: cur_steg_mod.second->extensions)
+      payload_server->extension_to_content_type_map[cur_supported_extension] = cur_steg_mod.second->content_type_id();
+
   //TODO: for now only one steg module can be mentioned for testing.
   //It should be that a comma separated list should be able to
   //activate

src/steg/http_steg_mods/file_steg.cc

@@ -88,13 +88,13 @@ ssize_t
 FileStegMod::extract_appropriate_respones_body(evbuffer* payload_buf)
 {
   //TODO: this need to be investigated, we might need two functions
-  const evbuffer_ptr hend = evbuffer_search(payload_buf, "\r\n\r\n", sizeof ("\r\n\r\n") -1 , NULL);
+  const evbuffer_ptr hend = evbuffer_search(payload_buf, end_of_header_indicator.c_str(), end_of_header_indicator.length() -1 , NULL);
   if (hend.pos == -1) {
     log_debug("unable to find end of header in the HTTP respose");
     return RESPONSE_INCOMPLETE;
   }
 
-  return hend.pos + strlen("\r\n\r\n");
+  return hend.pos + end_of_header_indicator.length();
 
 }
 
@@ -249,21 +249,19 @@ FileStegMod::http_server_transmit(evbuffer *source, conn_t *conn)
       log_debug("SERVER FileSteg sends resp with hdr len %zu body len %zd",
                 body_offset, outbuflen);
 
-      if ((size_t)outbuflen == body_len) {
-        log_assert(hLen < MAX_RESP_HDR_SIZE);
-        newHdr.assign(cover_payload.begin(), cover_payload.begin()+hLen);
-        newHdrLen = hLen;
-
-      }
-      else { //if the length is different, then we need to update the header
-        alter_length_in_response_header(cover_payload, outbuflen, newHdr);
-        newHdrLen = newHdr.size();
+      //TODO: handle HTTP chunked transfer.
+      //We need to check if set the header has a Content-length field
 
-        if (!newHdrLen) {
-          log_warn("SERVER ERROR: failed to alter length field in response headerr");
-          _payload_server.disqualify_payload(payload_id_hash);
-          goto error;
-        }
+      log_assert(hLen < MAX_RESP_HDR_SIZE);
+      vector<uint8_t> original_header(cover_payload.begin(), cover_payload.begin()+hLen);
+      //now we update the header
+      alter_length_in_response_header(original_header, outbuflen, newHdr);
+      newHdrLen = newHdr.size();
+
+      if (!newHdrLen) {
+        log_warn("SERVER ERROR: failed to alter length field in response headerr");
+        _payload_server.disqualify_payload(payload_id_hash);
+        goto error;
       }
 
       //All is good. send it off
@@ -371,35 +369,47 @@ FileStegMod::http_client_receive(conn_t *conn, struct evbuffer *dest,
 }
 
 void
-FileStegMod::alter_length_in_response_header(const std::vector<uint8_t>& payload_with_original_header, ssize_t new_content_length, std::vector<uint8_t>& new_header)
+FileStegMod::alter_length_in_response_header(const std::vector<uint8_t>& original_header, ssize_t new_content_length, std::vector<uint8_t>& new_header)
 {
-  static const string length_field_name = "Content-Length:";
-  static const string end_of_field_indicator = "\r\n";
-
-  //TODO: replace these with vector search
-  auto length_field_start = std::search(payload_with_original_header.begin(), payload_with_original_header.end(), length_field_name.begin(), length_field_name.end());
-  if (length_field_start == payload_with_original_header.end()) {
-    log_warn("payload with bad header. unable to find the Content-Length field");
-    return;
-  }
-
-  length_field_start += length_field_name.length();
+  string new_content_length_str(std::to_string(new_content_length));
+  vector<uint8_t>::const_iterator length_field_end;
 
-  auto length_field_end = std::search(length_field_start, payload_with_original_header.end(), end_of_field_indicator.begin(), end_of_field_indicator.end());
-  if (length_field_end ==  payload_with_original_header.end()) {
-    log_warn("payload with bad header. unable to find the end of Content-Length field.");
-    return;
-  }
+  auto length_field_start = std::search(original_header.begin(), original_header.end(), length_field_name.begin(), length_field_name.end());
+  if (length_field_start == original_header.end()) {
+    log_warn("unable to find the Content-Length field, adding the field...");
 
+    //TODO: this not the correct behavoir and can work as a descriminator.
+    //we need to add decocding length from chunk the client side instead
+
+    //we are addining it at the end
+    length_field_end = original_header.end() - end_of_header_indicator.length();
+    new_header.insert(new_header.end(), original_header.begin(), length_field_end);
+    //insert an end of field
+    new_header.insert(new_header.end(), end_of_field_indicator.begin(), end_of_field_indicator.end());
+    //insert the content-length field
+    new_header.insert(new_header.end(), length_field_name.begin(), length_field_name.end());
+
+  } else {
 
-  //copy the first part of the header
-  new_header.insert(new_header.end(), payload_with_original_header.begin(), length_field_start);
-  //memcpy(new_header, payload_with_original_header.data(), ((uint8_t*)length_field_start - original_header));
-  string new_content_length_str(std::to_string(new_content_length));
+    length_field_start += length_field_name.length();
+
+    length_field_end = std::search(length_field_start, original_header.end(), end_of_field_indicator.begin(), end_of_field_indicator.end());
+    if (length_field_end ==  original_header.end()) {
+      log_warn("payload with bad header. unable to find the end of Content-Length field.");
+      return;
+    }
+
+    //copy the first part of the header
+    new_header.insert(new_header.end(), original_header.begin(), length_field_start);
+
+  }
 
+  //either way copy the new length after space
+  new_header.push_back(' ');
   new_header.insert(new_header.end(), new_content_length_str.begin(), new_content_length_str.end());
+
   //copy the rest of the header
-  new_header.insert(new_header.end(), length_field_end,  payload_with_original_header.end());
+  new_header.insert(new_header.end(), length_field_end,  original_header.end());
 
 }
 

src/steg/http_steg_mods/file_steg.h

@@ -6,7 +6,6 @@
 
 #include <memory>
 #include <algorithm>
-#include <list>
 #include <math.h>
 
 using namespace std;
@@ -29,6 +28,10 @@ class FileStegMod
   const int RESPONSE_INCOMPLETE = -1;
   const int RESPONSE_BAD = -2;
 
+  const string length_field_name = "Content-Length:";
+  const string end_of_field_indicator = "\r\n";
+  const string end_of_header_indicator = "\r\n\r\n";
+
   //the payload server will be passed to us by the http steg mod
   //we are going to share the payload server with other file steg mods
   //Ultimately it is the http steg mod who is the owner.
@@ -115,7 +118,7 @@ class FileStegMod
 
   //list of file extensions/suffix which are representing files of type
   //handled by the module (e.g.: *.jpg *.jpeg etc)
-  const list<string> extensions;
+  vector<string> extensions;
 
   /**
      embed the data in the cover buffer, the assumption is that

src/steg/http_steg_mods/htmlSteg.cc

@@ -192,6 +192,8 @@ HTMLSteg::decode_http_body(const std::vector<uint8_t>& cover_and_data, std::vect
 HTMLSteg::HTMLSteg(PayloadServer& payload_provider, double noise2signal)
   :JSSteg(payload_provider, noise2signal, HTTP_CONTENT_HTML)
 {
-  //correcting the type
-
+  //adding extensions this module support
+  vector<string> supported_extension_list({"html", "htm", "shtml", "php"});
+  extensions = supported_extension_list;
+
 }

src/steg/http_steg_mods/jpgSteg.cc

@@ -144,4 +144,8 @@ ssize_t JPGSteg::decode(const std::vector<uint8_t>& cover_payload, std::vector<u
 JPGSteg::JPGSteg(PayloadServer& payload_provider, double noise2signal)
   :FileStegMod(payload_provider, noise2signal, HTTP_CONTENT_JPEG)
 {
+    //adding extensions this module support only if the type is JS (not being called by HTML CONST)
+  vector<string> supported_extension_list({"jpg", "jpeg"});
+  extensions = supported_extension_list;
+
 }

src/steg/http_steg_mods/jsSteg.cc

@@ -518,13 +518,15 @@ JSSteg::encode(const std::vector<uint8_t>& data, std::vector<uint8_t>& cover_pay
       return -1;
     }
 
-    cover_with_data = outbuf2;
+    cover_payload = outbuf2;
 
-  }
+  } else {
   //encCnt isn't really needed any more except for debugging and tracking, but return value outbuf2len is needed for new header
   //return encCnt;
-  cover_payload = cover_with_data;
-  return cover_with_data.size();
+    cover_payload = cover_with_data;
+  }
+
+  return cover_payload.size();
 
 }
 
@@ -715,6 +717,11 @@ void JSSteg::printerr(int err_no) /* name errno had conflict with other vars so
 JSSteg::JSSteg(PayloadServer& payload_provider, double noise2signal, int content_type)
  :FileStegMod(payload_provider, noise2signal, content_type)
 {
+  //adding extensions this module support only if the type is JS (not being called by HTML CONST)
+  if (content_type == CONTENT_JAVASCRIPT) {
+    vector<string> supported_extension_list({"js", "JS"});
+    extensions = supported_extension_list;
+  }
 
 }