Diff: DS2476.cpp

Revision:

0:33d4e66780c0

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DS2476.cpp	Fri Feb 24 11:23:12 2017 -0600
@@ -0,0 +1,126 @@
+/*******************************************************************************
+* Copyright (C) 2017 Maxim Integrated Products, Inc., All Rights Reserved.
+*
+* Permission is hereby granted, free of charge, to any person obtaining a
+* copy of this software and associated documentation files (the "Software"),
+* to deal in the Software without restriction, including without limitation
+* the rights to use, copy, modify, merge, publish, distribute, sublicense,
+* and/or sell copies of the Software, and to permit persons to whom the
+* Software is furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included
+* in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
+* OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+* OTHER DEALINGS IN THE SOFTWARE.
+*
+* Except as contained in this notice, the name of Maxim Integrated
+* Products, Inc. shall not be used except as stated in the Maxim Integrated
+* Products, Inc. Branding Policy.
+*
+* The mere transfer of this software does not imply any licenses
+* of trade secrets, proprietary technology, copyrights, patents,
+* trademarks, maskwork rights, or any other form of intellectual
+* property whatsoever. Maxim Integrated Products, Inc. retains all
+* ownership rights.
+*******************************************************************************/
+
+#include <I2C.h>
+#include <wait_api.h>
+#include "DS2476.hpp"
+
+// DS2476 additional commands.
+enum Command
+{
+    GenerateEcdsaSignature = 0x1E,
+    ComputeSha2UniqueSecret = 0x55,
+    ComputeSha2Hmac = 0x2D
+};
+
+DS2476::CmdResult DS2476::generateEcdsaSignature(KeyNum keyNum, Signature & signature)
+{
+    if (keyNum == KeyNumS)
+    {
+        return InvalidParameterError;
+    }
+    
+    Buffer buffer;
+    buffer.push_back(keyNum);
+    CmdResult result = writeCommand(GenerateEcdsaSignature, buffer);
+    if (result == Success)
+    {
+        wait_ms(generateEcdsaSignatureTimeMs);
+        result = readResponse(buffer);
+        if (result == Success)
+        {
+            if (buffer.size() == (1 + signature.r.size() + signature.s.size()))
+            {
+                result = convertResultByte(buffer[0]);
+                Buffer::const_iterator begin = buffer.begin() + 1;
+                Buffer::const_iterator end = begin + signature.s.size();
+                std::copy(begin, end, signature.s.begin());
+                begin = end;
+                end = begin + signature.r.size();
+                std::copy(begin, end, signature.r.begin());
+            }
+            else
+            {
+                result = CommunicationError;
+            }
+        }
+    }
+    return result;
+}
+
+DS2476::CmdResult DS2476::computeSha2UniqueSecret(SecretNum msecretNum)
+{
+    Buffer buffer;
+    buffer.push_back(msecretNum << 4);
+    CmdResult result = writeCommand(ComputeSha2UniqueSecret, buffer);
+    if (result == Success)
+    {
+        wait_ms(sha256ComputationTimeMs);
+        result = readResponse(buffer);
+        if (result == Success)
+        {
+            if (buffer.size() == 1)
+            {
+                convertResultByte(buffer[0]);
+            }
+            else
+            {
+                result = CommunicationError;
+            }
+        }
+    }
+    return result;
+}
+
+DS2476::CmdResult DS2476::computeSha2Hmac(HMAC & hmac)
+{
+    Buffer buffer;
+    CmdResult result = writeCommand(ComputeSha2Hmac, buffer);
+    if (result == Success)
+    {
+        wait_ms(sha256ComputationTimeMs);
+        result = readResponse(buffer);
+        if (result == Success)
+        {
+            if (buffer.size() == (1 + hmac.size()))
+            {
+                result = convertResultByte(buffer[0]);
+                std::copy(buffer.begin() + 1, buffer.end(), hmac.begin());
+            }
+            else
+            {
+                result = CommunicationError;
+            }
+        }
+    }
+    return result;
+}