commit 8846669ca95892dbbb84c1843d495202dc31f668
author John Chung <john.chung@arm.com> Wed Jun 25 11:27:18 2025 -0500
committer John Chung <john.chung@arm.com> Tue Jul 08 16:31:58 2025 +0000
tree eb44b025937b005ad1675b8af935a23bb31719f2
parent 99556a1fc93340954070c5b3e8527a598d072751

serialbridge: Fix checksum data byte escaping

Checksum in response packet should check for data byte escaping.

Tested with ipmitool.

Change-Id: I6b0fbb635480adfb87d8cbef6feca8bed6213f34
Signed-off-by: John Chung <john.chung@arm.com>

transport/serialbridge/serialcmd.cpp

diff --git a/transport/serialbridge/serialcmd.cpp b/transport/serialbridge/serialcmd.cpp
index 696515a..68622d8 100644
--- a/transport/serialbridge/serialcmd.cpp
+++ b/transport/serialbridge/serialcmd.cpp
@@ -188,13 +188,15 @@
 
         // Assemble connection header and checksum
         checksum = processEscapedCharacter(responseBuffer, connectionHeader);
-        responseBuffer.push_back(-checksum); // checksum1
+        checksum = static_cast<uint8_t>(~checksum + 1); // checksum1
+        processEscapedCharacter(responseBuffer, std::vector<uint8_t>{checksum});
 
         // Assemble response message and checksum
         checksum = processEscapedCharacter(responseBuffer, messageHeader);
         checksum +=
             processEscapedCharacter(responseBuffer, std::vector<uint8_t>(data));
-        responseBuffer.push_back(-checksum); // checksum2
+        checksum = static_cast<uint8_t>(~checksum + 1); // checksum2
+        processEscapedCharacter(responseBuffer, std::vector<uint8_t>{checksum});
 
         // bmStop
         responseBuffer.push_back(bmStop);