braice · hack03er · Apr 23, 2024 · Oct 17, 2024 · May 21, 2024 · Aug 19, 2024
diff --git a/configure.ac b/configure.ac
@@ -153,6 +153,18 @@ then
   AC_DEFINE(TUNE_OLD, 1, Define if you want the old code for tuning)
 fi
 
+AC_ARG_ENABLE([rewrite_nit_support],
+  [AS_HELP_STRING([--enable-rewrite_nit_support],
+    [Build with rewrite NIT support (default disabled)])],
+  [],
+  [enable_rewrite_nit_support="no"])
+
+if test "${enable_rewrite_nit_support}" = "yes"
+then
+  AC_DEFINE(REWRITE_NIT_SUPPORT, 1, Define if you want to rewrite the NIT Table)
+fi
+AM_CONDITIONAL([BUILD_REWRITE_NIT], [test "${enable_rewrite_nit_support}" = "yes"])
+
 # Checks for header files.
 AC_HEADER_RESOLV
 AC_CHECK_HEADERS([arpa/inet.h fcntl.h netdb.h netinet/in.h stdint.h stdlib.h string.h sys/ioctl.h sys/socket.h sys/time.h syslog.h unistd.h values.h])
@@ -220,6 +232,12 @@ if test "${enable_tune_old}" = "yes" ; then
         echo "Build with old tuning code:                         yes"
 fi
 
+if test "${enable_rewrite_nit_support}" = "yes" ; then
+        echo "Build with rewrite nit support:                     yes"
+else
+        echo "Build with rewrite nit support:                      no"
+fi
+
 echo ""
 echo "Debugging"
 echo ""

diff --git a/doc/README.asciidoc b/doc/README.asciidoc
@@ -111,6 +111,7 @@ The `[configure options]` specific to MuMuDVB are:
   --enable-duma           Debbuging DUMA library (default disabled)
   --enable-android        Support for Android (default disabled)
   --disable-dvb-support   Build without Linux DVB-API support, even on systems where the headers are present
+  --enable-rewrite_nit_support Build with rewrite nit support
 ---------------------------------------------------------------------
 
 [NOTE]

diff --git a/doc/README_CONF.asciidoc b/doc/README_CONF.asciidoc
@@ -222,7 +222,9 @@ Packets sending parameters
 |rewrite_pmt | Do we rewrite the PMT PID | 0 | 0 or 1 | See README, important if you don't stream all PIDs
 |rewrite_eit sort_eit | Do we rewrite/sort the EIT PID | 0 | 0 or 1 | See README 
 |sdt_force_eit | Do we force the EIT_schedule_flag and EIT_present_following_flag in SDT | 0 | 0 or 1 | Set to 0 if you don't understand
-|rtp_header | Send the stream with the rtp headers (except for HTTP unicast) | 0 | 0 or 1 | 
+|rtp_header | Send the stream with the rtp headers (except for HTTP unicast) | 0 | 0 or 1 |
+|rewrite_nit | Patch certain frequencies in the nit table | 0 | 0 or 1 | see freq_patch and configure options
+|freq_patch | Map the old frequency given as a hexadecimal value to a new frequency. For example `freq_patch=0x03300000->0x07700000` will rewrite the nit entry with the frequency 330MHz to 770MHz| | `%x->%x` | rewrite_nit needs to be enabled
 |==================================================================================================================
 
 Logs parameters

diff --git a/doc/html/README.html b/doc/html/README.html
@@ -4,7 +4,7 @@
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
 <head>
 <meta http-equiv="Content-Type" content="application/xhtml+xml; charset=UTF-8" />
-<meta name="generator" content="AsciiDoc 9.0.0rc1" />
+<meta name="generator" content="AsciiDoc 10.1.2" />
 <title>MuMuDVB - README</title>
 <style type="text/css">
 /* Shared CSS for AsciiDoc xhtml11 and html5 backends */
@@ -738,9 +738,9 @@ <h1>MuMuDVB - README</h1>
 <span id="author">Brice Dubost</span><br />
 <span id="email"><code>&lt;<a href="mailto:mumudvb@braice.net">mumudvb@braice.net</a>&gt;</code></span><br />
 <span id="revdate">Version 2.1.0</span>
-<div id="toc">
-  <div id="toctitle">Table of Contents</div>
-  <noscript><p><b>JavaScript must be enabled in your browser to display the table of contents.</b></p></noscript>
+<div id="toc">
+  <div id="toctitle">Table of Contents</div>
+  <noscript><p><b>JavaScript must be enabled in your browser to display the table of contents.</b></p></noscript>
 </div>
 </div>
 <div id="content">
@@ -949,7 +949,8 @@ <h4 id="_from_a_release_package">4.1.2. From a release package</h4>
   --enable-coverage       build for test coverage (default disabled)
   --enable-duma           Debbuging DUMA library (default disabled)
   --enable-android        Support for Android (default disabled)
-  --disable-dvb-support   Build without Linux DVB-API support, even on systems where the headers are present</code></pre>
+  --disable-dvb-support   Build without Linux DVB-API support, even on systems where the headers are present
+  --enable-rewrite_nit_support Build with rewrite nit support</code></pre>
 </div></div>
 <div class="admonitionblock">
 <table><tr>
@@ -1956,7 +1957,7 @@ <h4 id="_mythtv_configuration">17.2.2. Mythtv configuration:</h4>
 <div id="footer">
 <div id="footer-text">
 Last updated
- 2024-03-23 16:36:54 CET
+ 2025-01-16 13:47:47 CET
 </div>
 </div>
 </body>

diff --git a/doc/html/README_CONF.html b/doc/html/README_CONF.html
@@ -4,7 +4,7 @@
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
 <head>
 <meta http-equiv="Content-Type" content="application/xhtml+xml; charset=UTF-8" />
-<meta name="generator" content="AsciiDoc 9.0.0rc1" />
+<meta name="generator" content="AsciiDoc 10.1.2" />
 <title>MuMuDVB - README for the configuration file</title>
 <style type="text/css">
 /* Shared CSS for AsciiDoc xhtml11 and html5 backends */
@@ -738,9 +738,9 @@ <h1>MuMuDVB - README for the configuration file</h1>
 <span id="author">Brice Dubost</span><br />
 <span id="email"><code>&lt;<a href="mailto:mumudvb@braice.net">mumudvb@braice.net</a>&gt;</code></span><br />
 <span id="revdate">Version 2.1.0</span>
-<div id="toc">
-  <div id="toctitle">Table of Contents</div>
-  <noscript><p><b>JavaScript must be enabled in your browser to display the table of contents.</b></p></noscript>
+<div id="toc">
+  <div id="toctitle">Table of Contents</div>
+  <noscript><p><b>JavaScript must be enabled in your browser to display the table of contents.</b></p></noscript>
 </div>
 </div>
 <div id="content">
@@ -1445,6 +1445,20 @@ <h3 id="_packets_sending_parameters">4.3. Packets sending parameters</h3>
 <td align="left" valign="top"><p class="table">0 or 1</p></td>
 <td align="left" valign="top"><p class="table"></p></td>
 </tr>
+<tr>
+<td align="left" valign="top"><p class="table">rewrite_nit</p></td>
+<td align="left" valign="top"><p class="table">Patch certain frequencies in the nit table</p></td>
+<td align="left" valign="top"><p class="table">0</p></td>
+<td align="left" valign="top"><p class="table">0 or 1</p></td>
+<td align="left" valign="top"><p class="table">see freq_patch and configure options</p></td>
+</tr>
+<tr>
+<td align="left" valign="top"><p class="table">freq_patch</p></td>
+<td align="left" valign="top"><p class="table">Map the old frequency given as a hexadecimal value to a new frequency. For example <code>freq_patch=0x03300000-&gt;0x07700000</code> will rewrite the nit entry with the frequency 330MHz to 770MHz</p></td>
+<td align="left" valign="top"><p class="table"></p></td>
+<td align="left" valign="top"><p class="table"><code>%x-&gt;%x</code></p></td>
+<td align="left" valign="top"><p class="table">rewrite_nit needs to be enabled</p></td>
+</tr>
 </tbody>
 </table>
 </div>
@@ -2129,7 +2143,7 @@ <h4 id="_scan_only_one_transponder">4.11.3. Scan only one transponder</h4>
 <div id="footer">
 <div id="footer-text">
 Last updated
- 2024-03-23 16:36:54 CET
+ 2025-01-16 14:46:57 CET
 </div>
 </div>
 </body>

diff --git a/src/Makefile.am b/src/Makefile.am
@@ -38,3 +38,6 @@ SOURCES_scamsupport = \
 	scam_send.h \
         $(NULL)
 
+if BUILD_REWRITE_NIT
+mumudvb_SOURCES += rewrite_nit.c
+endif
diff --git a/src/autoconf_nit.c b/src/autoconf_nit.c
@@ -143,7 +143,7 @@ int autoconf_read_nit(auto_p_t *auto_p, mumu_chan_p_t *chan_p)
 	buf += network_descriptors_length;
 	nit_mid_t *middle=(nit_mid_t *)buf;
 	int ts_loop_length=HILO(middle->transport_stream_loop_length);
-	buf +=SIZE_NIT_MID;
+	buf += SIZE_NIT_MID;
 	parse_nit_ts_descriptor(buf,ts_loop_length, chan_p->channels, chan_p->number_of_channels, auto_p->transport_stream_id);
 
 
@@ -199,23 +199,26 @@ void parse_nit_ts_descriptor(unsigned char* buf, int ts_descriptors_loop_len, mu
 				break;
 			}
 			//We parse only descriptors with the right transport_stream_id
-			if(pat_tsid==ts_id)
-			{
-				if(descriptor_tag==0x83)
-				{
+			if(pat_tsid==ts_id) {
+				if(descriptor_tag==0x83) {
 					ts_display_lcn_descriptor(log_module, buf);
 					parse_lcn_descriptor(buf, channels, number_of_channels);
-				}
-				else if(descriptor_tag==0x41)
-					ts_display_service_list_descriptor(log_module, buf);
-				else if(descriptor_tag==0x43)
-					ts_display_satellite_delivery_system_descriptor(log_module, buf);
-				else if(descriptor_tag==0x5A)
-					ts_display_terrestrial_delivery_system_descriptor(log_module, buf);
-				else if(descriptor_tag==0x62)
-					ts_display_frequency_list_descriptor(log_module, buf);
-				else
+				} else if(descriptor_tag==0x41) {
+                    ts_display_service_list_descriptor(log_module, buf);
+                } else if(descriptor_tag==0x43) {
+                    ts_display_satellite_delivery_system_descriptor(log_module, buf);
+                } else if(descriptor_tag==0x44) {
+                    log_message(log_module, MSG_FLOOD, " --- NIT TS descriptor --- cable delivery system descriptor "
+                                                       "len %d descriptors_loop_len %d ------------\n",
+                                                       descriptor_len, descriptors_loop_len);
+                    ts_display_cable_delivery_system_descriptor(log_module, buf);
+                } else if(descriptor_tag==0x5A) {
+                    ts_display_terrestrial_delivery_system_descriptor(log_module, buf);
+                } else if(descriptor_tag==0x62) {
+                    ts_display_frequency_list_descriptor(log_module, buf);
+                } else {
 					log_message( log_module, MSG_FLOOD, " --- NIT TS descriptor --- descriptor_tag == 0x%02x len %d descriptors_loop_len %d ------------\n", descriptor_tag, descriptor_len, descriptors_loop_len);
+                }
 			}
 			buf += descriptor_len;
 			descriptors_loop_len -= descriptor_len;

diff --git a/src/crc32.c b/src/crc32.c
@@ -27,7 +27,10 @@
  * it contains the precomputed table
  */
 
+#include "crc32.h"
+
 #include <stdint.h>
+#include "ts.h"
 
 /**CRC table for PAT rebuilding, cam support and autoconfiguration*/
 uint32_t crc32_table[256] =
@@ -98,3 +101,34 @@ uint32_t crc32_table[256] =
 	0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
 };
 
+/**
+ * @brief CRC32 calculation inspired by the xine project
+ * @param data to be hashed
+ * @param len of data
+ * @return CRC32 value of data
+ */
+unsigned long calculateCRC32(const unsigned char *data, int len)
+{
+    // Now we must adjust the CRC32
+    unsigned long crc32 = 0xffffffff;
+    for (int i = 0; i < len; ++i) {
+        crc32 = (crc32 << 8) ^ crc32_table[((crc32 >> 24) ^ data[i]) & 0xff];
+    }
+    return crc32;
+}
+
+/**
+ * @brief Calculates and sets CRC32 for PAT, EIT, SDT, PMT, NIT
+ * @param data pointer to table
+ */
+void setCRC32(unsigned char *data)
+{
+    tbl_h_t *table = (tbl_h_t *)data;
+    int len = 3 + HILO(table->section_length) - 4; // CRC for complete section but CRC (4 Bytes)
+    unsigned long crc32 = calculateCRC32(data, len);
+    // We write the CRC32 to the buffer
+    data[len] = (crc32 >> 24) & 0xff;
+    data[len + 1] = (crc32 >> 16) & 0xff;
+    data[len + 2] = (crc32 >> 8) & 0xff;
+    data[len + 3] = crc32 & 0xff;
+}
diff --git a/src/crc32.h b/src/crc32.h
@@ -0,0 +1,12 @@
+#ifndef _CRC32_H
+#define _CRC32_H
+
+#include <stdint.h>
+
+extern uint32_t crc32_table[256];
+
+unsigned long calculateCRC32(const unsigned char *data, int len);
+
+void setCRC32(unsigned char *data);
+
+#endif //_CRC32_H
diff --git a/src/log.c b/src/log.c
@@ -989,6 +989,9 @@ void print_info ()
 #ifdef DVBT2
 			"Built with support for DVB-T2.\n"
 #endif
+#ifdef REWRITE_NIT_SUPPORT
+			"Built with rewrite nit support.\n"
+#endif
 #endif
 			"---------\n"
 			"Originally based on dvbstream 0.6 by (C) Dave Chapman 2001-2004\n"

diff --git a/src/mumudvb.c b/src/mumudvb.c
@@ -504,6 +504,12 @@ int main (int argc, char **argv)
 			if(iRet==-1)
 				exit(ERROR_CONF);
 		}
+#ifdef REWRITE_NIT_SUPPORT
+		else if((iRet=read_rewrite_nit_config(substring))) {
+			if (iRet==-1)
+				exit(ERROR_CONF);
+		}
+#endif // REWRITE_NIT_SUPPORT
 		else if((iRet=read_logging_configuration(&stats_infos, substring))) //Read the line concerning the logging parameters
 		{
 			if(iRet==-1)
@@ -1636,6 +1642,16 @@ int main (int argc, char **argv)
 			{
 				eit_rewrite_new_global_packet(actual_ts_packet, &rewrite_vars);
 			}
+#ifdef REWRITE_NIT_SUPPORT
+			/******************************************************/
+			//NIT rewrite
+			/******************************************************/
+			if ((pid == 0x10) && //This is a NIT PID
+				rewrite_vars.rewrite_nit == OPTION_ON) //AND we asked for rewrite
+			{
+				nit_rewrite_new_global_packet(actual_ts_packet, &rewrite_vars);
+			}
+#endif // REWRITE_NIT_SUPPORT
 
 
 			/******************************************************/