[DiagnosticLogs] Allow TransferFileDesignator or size 0 (#32267)

Author: vivien-apple

examples/chip-tool/commands/common/BDXDiagnosticLogsServerDelegate.cpp

@@ -25,9 +25,10 @@ constexpr uint8_t kMaxFileDesignatorLen = 32;
 constexpr uint16_t kMaxFilePathLen      = kMaxFileDesignatorLen + sizeof(kTmpDir) + 1;
 
 // For testing a few file names trigger an error depending on the current 'phase'.
-constexpr char kErrorOnTransferBegin[] = "Error:OnTransferBegin";
-constexpr char kErrorOnTransferData[]  = "Error:OnTransferData";
-constexpr char kErrorOnTransferEnd[]   = "Error:OnTransferEnd";
+constexpr char kErrorOnTransferBegin[]            = "Error:OnTransferBegin";
+constexpr char kErrorOnTransferData[]             = "Error:OnTransferData";
+constexpr char kErrorOnTransferEnd[]              = "Error:OnTransferEnd";
+constexpr char kErrorTransferMethodNotSupported[] = "TransferMethodNotSupported.txt";
 
 BDXDiagnosticLogsServerDelegate BDXDiagnosticLogsServerDelegate::sInstance;
 
@@ -136,8 +137,14 @@ CHIP_ERROR BDXDiagnosticLogsServerDelegate::OnTransferBegin(chip::bdx::BDXTransf
     auto fileDesignator = transfer->GetFileDesignator();
     LogFileDesignator("OnTransferBegin", fileDesignator);
 
+    VerifyOrReturnError(fileDesignator.size() != 0, CHIP_ERROR_UNKNOWN_RESOURCE_ID);
+
     chip::CharSpan phaseErrorTarget(kErrorOnTransferBegin, sizeof(kErrorOnTransferBegin) - 1);
     ReturnErrorOnFailure(CheckForErrorRequested(phaseErrorTarget, fileDesignator));
+
+    chip::CharSpan transferErrorTarget(kErrorTransferMethodNotSupported, sizeof(kErrorTransferMethodNotSupported) - 1);
+    VerifyOrReturnError(!transferErrorTarget.data_equal(fileDesignator), CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE);
+
     ReturnErrorOnFailure(CheckFileDesignatorAllowed(mFileDesignators, fileDesignator));
 
     char outputFilePath[kMaxFilePathLen] = { 0 };

src/app/clusters/diagnostic-logs-server/diagnostic-logs-server.cpp

@@ -132,8 +132,6 @@ void DiagnosticLogsServer::HandleLogRequestForBdx(CommandHandler * commandObj, c
     // INVALID_COMMAND.
     VerifyOrReturn(transferFileDesignator.HasValue(), commandObj->AddStatus(path, Status::InvalidCommand));
 
-    VerifyOrReturn(transferFileDesignator.Value().size() > 0, commandObj->AddStatus(path, Status::ConstraintError));
-
     VerifyOrReturn(transferFileDesignator.Value().size() <= kMaxFileDesignatorLen,
                    commandObj->AddStatus(path, Status::ConstraintError));
 

src/protocols/bdx/BdxTransferProxyDiagnosticLog.cpp

@@ -33,7 +33,6 @@ CHIP_ERROR BDXTransferProxyDiagnosticLog::Init(TransferSession * transferSession
     uint16_t fileDesignatorLength = 0;
     auto fileDesignator           = transferSession->GetFileDesignator(fileDesignatorLength);
 
-    VerifyOrReturnError(fileDesignatorLength > 0, CHIP_ERROR_INVALID_STRING_LENGTH);
     VerifyOrReturnError(fileDesignatorLength <= ArraySize(mFileDesignator), CHIP_ERROR_INVALID_STRING_LENGTH);
 
     mTransfer          = transferSession;

src/protocols/bdx/StatusCode.cpp

@@ -33,6 +33,14 @@ StatusCode GetBdxStatusCodeFromChipError(CHIP_ERROR error)
     {
         status = StatusCode::kBadMessageContents;
     }
+    else if (error == CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE)
+    {
+        status = StatusCode::kTransferMethodNotSupported;
+    }
+    else if (error == CHIP_ERROR_UNKNOWN_RESOURCE_ID)
+    {
+        status = StatusCode::kFileDesignatorUnknown;
+    }
 
     return status;
 }