Fix UDP checksum

xfangfang · May 26, 2024 · 23a9e35 · 23a9e35
1 parent 8558b2e
commit 23a9e35
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Showing 2 changed files with 5 additions and 5 deletions.
diff --git a/src/exploit.cpp b/src/exploit.cpp
@@ -1026,10 +1026,10 @@ int Exploit::stage4() {
 
             // Calculate checksum
             std::vector<uint8_t> temp(udpLayer.getHeaderLen());
-            V16(temp, 0, udpHeader->portSrc);
-            V16(temp, 2, udpHeader->portDst);
-            V16(temp, 4, udpHeader->length);
-            V16(temp, 6, 0);
+            (*(uint16_t *) &(temp)[0]) = udpHeader->portSrc;
+            (*(uint16_t *) &(temp)[2]) = udpHeader->portDst;
+            (*(uint16_t *) &(temp)[4]) = udpHeader->length;
+            (*(uint16_t *) &(temp)[6]) = 0;
             temp.insert(temp.end(), this->stage2_bin.begin(), this->stage2_bin.end());
             uint16_t checksumRes = pcpp::computePseudoHdrChecksum(temp.data(),
                                                                   temp.size(),

diff --git a/tests/extern.cpp b/tests/extern.cpp
@@ -2,7 +2,7 @@
 #include <EndianPortable.h>
 
 #define COPY_TO_BUFFER(buffer, packet) \
-    memcpy(buffer, packet.getRawPacket()->getRawData(), size), packet.getRawPacket()->getRawDataLen()
+    size < packet.getRawPacket()->getRawDataLen() ? 0 : memcpy(buffer, packet.getRawPacket()->getRawData(), packet.getRawPacket()->getRawDataLen()), packet.getRawPacket()->getRawDataLen()
 
 #ifndef htole64
 #define htole64