Changeset 11130 in ntrip for trunk/BNC/src/RTCM3

Timestamp:

Oct 28, 2026, 9:32:30 AM (2 weeks ago)

Author:

stuerze

Message:

Some fixes from security point of view

Location:

trunk/BNC/src/RTCM3

Files:

• RTCM3Decoder.cpp (modified) (4 diffs)
• bits.h (modified) (2 diffs)
• clock_and_orbit/clock_orbit.h (modified) (1 diff)
• clock_and_orbit/clock_orbit_rtcm_new.cpp (modified) (1 diff)

trunk/BNC/src/RTCM3/RTCM3Decoder.cpp

@@ -39 +39 @@
  * -----------------------------------------------------------------------*/
 
+#include <atomic>
 #include <iostream>
 #include <iomanip>
@@ -241 +242 @@
 /**
  * Frequency numbers of GLONASS with an offset of 100 to detect unset values.
- * Gets filled by ephemeris and data blocks and shared between different streams.
+ * Gets filled by ephemeris and data blocks and shared between different streams
+ * (MSM4/6 streams without channel numbers use those of an ephemeris stream).
+ * Atomic, as the streams are decoded in different threads.
  */
-static int GLOFreq[RTCM3_MSM_NUMSAT];
+static std::atomic<int> GLOFreq[RTCM3_MSM_NUMSAT];
 
 /*
@@ -1998 +2001 @@
   GETSTRING(antnum, antenna)
   if ((antnum > -1 && antnum < 265) &&
-      (_antType.empty() || strncmp(_antType.back()._descriptor, antenna, recnum) != 0)) {
+      (_antType.empty() || int(strlen(_antType.back()._descriptor)) != antnum ||
+       strncmp(_antType.back()._descriptor, antenna, antnum) != 0)) {
     _antType.push_back(t_antInfo());
     memcpy(_antType.back()._descriptor, antenna, antnum);
@@ -2017 +2021 @@
     GETSTRING(recsernum, recserialnum)
     if ((recnum > -1 && recnum < 265) &&
-        (_recType.empty() || strncmp(_recType.back()._descriptor, receiver, recnum) != 0)) {
+        (_recType.empty() || int(strlen(_recType.back()._descriptor)) != recnum ||
+         strncmp(_recType.back()._descriptor, receiver, recnum) != 0)) {
       _recType.push_back(t_recInfo());
       memcpy(_recType.back()._descriptor, receiver, recnum);

trunk/BNC/src/RTCM3/bits.h

@@ -104 +104 @@
    b = variable to store size, s = variable to store string pointer */
 #define GETSTRING(b, s) { \
+  if(size < 1) return false; \
   b = *(data++); \
+  --size; \
+  if((b) > size) return false; \
   s = (char *) data; \
   data += b; \
-  size -= b+1; \
+  size -= b; \
 }
 
@@ -126 +129 @@
   }
 
+/* up to 56 bits: less than 8 bits are pending in the 64-bit bitbuffer */
 #define ADDBITS(a, b) { \
-    bitbuffer = (bitbuffer<<(a))|((b)&((1<<a)-1)); \
+    bitbuffer = (bitbuffer<<(a))|((uint64_t)(b)&((1ULL<<(a))-1)); \
     numbits += (a); \
     STOREBITS \

trunk/BNC/src/RTCM3/clock_and_orbit/clock_orbit.h

@@ -605 +605 @@
 #define E_NADIR_ANGLE_DEPENDENT_CORR_RANGE_EXTENSION(a) ADDBITS(4,  a)                      /* DF+015 (new RTCM) to extend DF+021*/
 #define E_SATELLITE_SET_INDICATOR(a)                    ADDBITS(1,  a)                      /* DF+016 (new RTCM) */
-/* ADDBITS' mask "(1<<a)-1" uses a 32-bit int literal, so a plain
-   ADDBITS(64, a) is broken the same way GETSSRBITS(a, 64) was on decode
-   (see D_SATELLITE_MASK) - here even ADDBITS(32, ...) is unsafe, since
-   shifting a 32-bit int by exactly its own width is undefined behavior
-   too. Stay well clear of that edge by writing four 16-bit chunks. */
+/* ADDBITS handles up to 56 bits, so the 64-bit mask is written as two
+   32-bit halves (as GETSSRBITS(a, 64) does not work either, see
+   D_SATELLITE_MASK). */
 #define E_SATELLITE_MASK(a)                             { \
   uint64_t mask64_ = (a); \
-  ADDBITS(16, (mask64_ >> 48) & 0xFFFFU) \
-  ADDBITS(16, (mask64_ >> 32) & 0xFFFFU) \
-  ADDBITS(16, (mask64_ >> 16) & 0xFFFFU) \
-  ADDBITS(16,  mask64_        & 0xFFFFU) \
+  ADDBITS(32, mask64_ >> 32) \
+  ADDBITS(32, mask64_ & 0xFFFFFFFFU) \
 }                                                                                           /* DF394 */
 #define E_FREQUENCY_SET_INDICATOR(a)                    ADDBITS(1,  a)                      /* DF+017 (new RTCM) */

trunk/BNC/src/RTCM3/clock_and_orbit/clock_orbit_rtcm_new.cpp

@@ -489 +489 @@
         if (md->Entries[i].nonDefaultIndicator &&
             md->Entries[i].additionalParameterIndicator) {
-          /* up to 255 bits, only 32 stored (leading bits zero); in pieces of
-             16 bits, as ADDBITS cannot handle more than 30 bits */
+          /* up to 255 bits, only 32 stored: leading zero bits (ADDBITS
+             handles at most 56 bits at a time), then the value */
           unsigned int k = md->Entries[i].additionalParameterNumBits;
-          while (k) {
-            unsigned int n = (k > 16) ? 16 : k;
+          while (k > 32) {
+            unsigned int n = (k - 32 > 56) ? 56 : k - 32;
+            ADDBITS(n, 0)
             k -= n;
-            E_ADDITIONAL_MODEL_PARAMETER_DATA((k < 32) ? (md->Entries[i].additionalParameterData >> k) : 0, n)
-          }
+          }
+          if (k)
+            E_ADDITIONAL_MODEL_PARAMETER_DATA(md->Entries[i].additionalParameterData, k)
       }
     }