subprojects/packagefiles/libpldm/0002-dsp-base-Omit-checksum-for-Multipart-receive-ACKNOWL.patch

From 4d2419632b6317efae974fb6695f844e62b47439 Mon Sep 17 00:00:00 2001
From: Kasun Athukorala <kasunath@google.com>
Date: Sat, 13 Sep 2025 00:37:59 +0000
Subject: [PATCH] dsp: base: Omit checksum for Multipart receive
 ACKNOWLEDGE_COMPLETION

This fix is based on DSP0240 v1.2.0 section 9.6.5 MultipartReceive.

DataIntegrityChecksum property should be there unless the
response TransferFlag property is ACKNOWLEDGE_COMPLETION

This patch fixes the issue where DataIntegrityChecksum is only
included if the TransferFlag is PLDM_END or PLDM_START_AND_END

gitlint-ignore: T1
Change-Id: I6d715d21d9d9d55bbda6139108be9cfb288ad209
Signed-off-by: Kasun Athukorala <kasunath@google.com>
---
 CHANGELOG.md       |  2 ++
 src/dsp/base.c     | 12 +++++++++---
 tests/dsp/base.cpp | 34 ++++++++++------------------------
 3 files changed, 21 insertions(+), 27 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b28a4fc..712c858 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -99,6 +99,8 @@ Change categories:
 - base:
   - Removed RequestedSectionOffset check in decode_multipart_receive_req()
   - Updated DataTransferHandle check in decode_multipart_receive_req()
+  - Updated encode_base_multipart_receive_resp() to insert checksum except when
+    TransferFlag is ACKNOWLEDGE_COMPLETION
 
 ### Security
 
diff --git a/src/dsp/base.c b/src/dsp/base.c
index eb0aaa4..e69d286 100644
--- a/src/dsp/base.c
+++ b/src/dsp/base.c
@@ -680,7 +680,11 @@ int encode_base_multipart_receive_resp(
 	PLDM_MSGBUF_RW_DEFINE_P(buf);
 	int rc;
 
-	if (!msg || !resp || !payload_length || !resp->data.ptr) {
+	if (!msg || !resp || !payload_length) {
+		return -EINVAL;
+	}
+
+	if ((resp->data.length > 0) && !resp->data.ptr) {
 		return -EINVAL;
 	}
 
@@ -725,8 +729,10 @@ int encode_base_multipart_receive_resp(
 		return pldm_msgbuf_discard(buf, rc);
 	}
 
-	if (resp->transfer_flag == PLDM_END ||
-	    resp->transfer_flag == PLDM_START_AND_END) {
+	// Checksum is present for all data parts except when response transfer flag is
+	// ACKNOWLEDGE_COMPLETION
+	if (resp->transfer_flag !=
+	    PLDM_BASE_MULTIPART_RECEIVE_TRANSFER_FLAG_ACK_COMPLETION) {
 		pldm_msgbuf_insert(buf, checksum);
 	}
 
diff --git a/tests/dsp/base.cpp b/tests/dsp/base.cpp
index b2e9294..88539ba 100644
--- a/tests/dsp/base.cpp
+++ b/tests/dsp/base.cpp
@@ -1093,37 +1093,23 @@ TEST(EncodeMultipartReceiveResponse, GoodTestWithoutChecksum)
 {
     uint8_t instance_id = 0;
     uint8_t completionCode = PLDM_SUCCESS;
-    uint8_t transferFlag = PLDM_BASE_MULTIPART_RECEIVE_TRANSFER_FLAG_START;
-    uint32_t nextDataTransferHandle = 0x16;
-    static constexpr const uint32_t dataLength = 9;
-    std::vector<uint8_t> data = {1, 2, 3, 4, 5, 6, 7, 8, 9};
+    uint8_t transferFlag =
+        PLDM_BASE_MULTIPART_RECEIVE_TRANSFER_FLAG_ACK_COMPLETION;
+    uint32_t nextDataTransferHandle = 0;
+    static constexpr const uint32_t dataLength = 0;
     static constexpr const size_t responseMsgLength =
         PLDM_BASE_MULTIPART_RECEIVE_RESP_MIN_BYTES + dataLength;
     size_t payload_length = responseMsgLength;
 
-    struct variable_field payload = {data.data(), dataLength};
+    struct variable_field payload = {nullptr, dataLength};
     struct pldm_base_multipart_receive_resp resp_data = {
         completionCode, transferFlag, nextDataTransferHandle, payload};
     std::array<uint8_t, responseMsgLength> responseMsg = {
-        completionCode,
-        transferFlag,
-        0x16, // nextDataTransferHandle
-        0x00,
-        0x00,
-        0x00,
-        0x09, // dataLength
-        0x00,
-        0x00,
-        0x00,
-        0x1, // data
-        0x2,
-        0x3,
-        0x4,
-        0x5,
-        0x6,
-        0x7,
-        0x8,
-        0x9};
+        completionCode, transferFlag,
+        0x00, // nextDataTransferHandle
+        0x00,           0x00,         0x00,
+        0x00, // dataLength
+        0x00,           0x00,         0x00};
 
     PLDM_MSG_DEFINE_P(responsePtr, responseMsgLength);
     int rc;
-- 
2.51.0.536.g15c5d4f767-goog