[ESP32] Implement providers which reads unique data from the secure c…

…ert partition

Right now secure cert partition stores only device attestation data i.e.
DAC and PAI. This can be extended to store the sort of unique data that
is discriminator, verifier/salt/iteration-count for passcode, and
unique-id for generating rotating id.

src/platform/ESP32/BUILD.gn

@@ -205,6 +205,13 @@ static_library("ESP32") {
     ]
   }
 
+  if (chip_use_factory_data_provider && chip_use_secure_cert_dac_provider) {
+    sources += [
+      "ESP32SecureCertDataProvider.cpp",
+      "ESP32SecureCertDataProvider.h",
+    ]
+  }
+
   if (chip_use_esp32_ecdsa_peripheral) {
     sources += [
       "ESP32CHIPCryptoPAL.cpp",

src/platform/ESP32/ESP32SecureCertDataProvider.cpp

@@ -0,0 +1,145 @@
+/*
+ *
+ *    Copyright (c) 2024 Project CHIP Authors
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include <esp_err.h>
+#include <esp_secure_cert_tlv_config.h>
+#include <esp_secure_cert_tlv_read.h>
+
+#include <lib/core/CHIPEncoding.h>
+#include <lib/support/CodeUtils.h>
+#include <lib/support/logging/CHIPLogging.h>
+#include <lib/support/span.h>
+#include <platform/ESP32/ESP32FactoryDataProvider.h>
+#include <platform/ESP32/ESP32SecureCertDataProvider.h>
+
+namespace chip {
+namespace DeviceLayer {
+
+namespace {
+// Define Matter-specific TLV subtypes for fields in the secure cert partition
+enum class MatterTLVSubType : uint8_t
+{
+    kSetupDiscriminator       = 0,
+    kSpake2pVerifier          = 1,
+    kSpake2pSalt              = 2,
+    kSpake2pIterationCount    = 3,
+    kRotatingDeviceIdUniqueId = 4,
+};
+
+// Scoped wrapper class for handling TLV data retrieval from secure cert partition
+class ScopedTLVInfo
+{
+public:
+    ScopedTLVInfo(MatterTLVSubType subType) : mTLVConfig(GetMatterTLVConfig(subType)) {}
+
+    ~ScopedTLVInfo() { esp_secure_cert_free_tlv_info(&mTLVInfo); }
+
+    CHIP_ERROR GetValue(MutableByteSpan & span)
+    {
+        ReturnErrorOnFailure(PopulateTLVInfo());
+        VerifyOrReturnError(mTLVInfo.length <= span.size(), CHIP_ERROR_BUFFER_TOO_SMALL);
+
+        memcpy(span.data(), mTLVInfo.data, mTLVInfo.length);
+        span.reduce_size(mTLVInfo.length);
+
+        return CHIP_NO_ERROR;
+    }
+
+    CHIP_ERROR GetValue(uint16_t & value)
+    {
+        ReturnErrorOnFailure(PopulateTLVInfo());
+        VerifyOrReturnError(mTLVInfo.length == sizeof(uint16_t), CHIP_ERROR_INTERNAL,
+                            ChipLogError(DeviceLayer, "secure cert tlv size mismatch"));
+
+        value = Encoding::LittleEndian::Get16(reinterpret_cast<const uint8_t *>(mTLVInfo.data));
+        ChipLogDetail(DeviceLayer, "secure cert tlv value:%u", value);
+        return CHIP_NO_ERROR;
+    }
+
+    CHIP_ERROR GetValue(uint32_t & value)
+    {
+        ReturnErrorOnFailure(PopulateTLVInfo());
+        VerifyOrReturnError(mTLVInfo.length == sizeof(uint32_t), CHIP_ERROR_INTERNAL,
+                            ChipLogError(DeviceLayer, "secure cert tlv size mismatch"));
+
+        value = Encoding::LittleEndian::Get32(reinterpret_cast<const uint8_t *>(mTLVInfo.data));
+        ChipLogDetail(DeviceLayer, "secure cert tlv value:%" PRIu32, value);
+        return CHIP_NO_ERROR;
+    }
+
+private:
+    esp_secure_cert_tlv_info_t mTLVInfo;
+    esp_secure_cert_tlv_config_t mTLVConfig;
+
+    esp_secure_cert_tlv_config_t GetMatterTLVConfig(MatterTLVSubType subType)
+    {
+        // Note: 201 is the Matter-specific TLV type defined in esp_secure_cert_tlv_config.h
+        // TODO: start using ESP_SECURE_CERT_MATTER_TLV_1 once available in esp_secure_cert_mgr
+        return { .type    = static_cast<esp_secure_cert_tlv_type_t>(201),
+                 .subtype = static_cast<esp_secure_cert_tlv_subtype_t>(subType) };
+    }
+
+    CHIP_ERROR PopulateTLVInfo()
+    {
+        esp_err_t err = esp_secure_cert_get_tlv_info(&mTLVConfig, &mTLVInfo);
+        VerifyOrReturnError(err == ESP_OK, CHIP_ERROR_INTERNAL,
+                            ChipLogError(DeviceLayer, "esp_secure_cert_get_tlv_info failed: type:%u, subtype:%u, err:%d",
+                                         mTLVConfig.type, mTLVConfig.subtype, err));
+
+        ChipLogDetail(DeviceLayer, "secure cert tlv info type:%u subtype:%u length:%" PRIu32 " flags:%u", mTLVInfo.type,
+                      mTLVInfo.subtype, mTLVInfo.length, mTLVInfo.flags);
+
+        return CHIP_NO_ERROR;
+    }
+};
+
+} // anonymous namespace
+
+CHIP_ERROR ESP32SecureCertDataProvider::GetSetupDiscriminator(uint16_t & setupDiscriminator)
+{
+    ScopedTLVInfo tlvInfo(MatterTLVSubType::kSetupDiscriminator);
+    return tlvInfo.GetValue(setupDiscriminator);
+}
+
+CHIP_ERROR ESP32SecureCertDataProvider::GetSpake2pIterationCount(uint32_t & iterationCount)
+{
+    ScopedTLVInfo tlvInfo(MatterTLVSubType::kSpake2pIterationCount);
+    return tlvInfo.GetValue(iterationCount);
+}
+
+CHIP_ERROR ESP32SecureCertDataProvider::GetSpake2pSalt(MutableByteSpan & saltBuf)
+{
+    ScopedTLVInfo tlvInfo(MatterTLVSubType::kSpake2pSalt);
+    return tlvInfo.GetValue(saltBuf);
+}
+
+CHIP_ERROR ESP32SecureCertDataProvider::GetSpake2pVerifier(MutableByteSpan & verifierBuf, size_t & verifierLen)
+{
+    ScopedTLVInfo tlvInfo(MatterTLVSubType::kSpake2pVerifier);
+    ReturnErrorOnFailure(tlvInfo.GetValue(verifierBuf));
+    verifierLen = verifierBuf.size();
+    return CHIP_NO_ERROR;
+}
+
+CHIP_ERROR ESP32SecureCertDataProvider::GetRotatingDeviceIdUniqueId(MutableByteSpan & uniqueIdSpan)
+{
+    ScopedTLVInfo tlvInfo(MatterTLVSubType::kRotatingDeviceIdUniqueId);
+    return tlvInfo.GetValue(uniqueIdSpan);
+}
+
+} // namespace DeviceLayer
+} // namespace chip

src/platform/ESP32/ESP32SecureCertDataProvider.h

@@ -0,0 +1,43 @@
+/*
+ *
+ *    Copyright (c) 2024 Project CHIP Authors
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#pragma once
+
+#include <platform/CommissionableDataProvider.h>
+#include <platform/ESP32/ESP32FactoryDataProvider.h>
+#include <platform/ESP32/ESP32SecureCertDACProvider.h>
+
+#include <esp_secure_cert_tlv_config.h>
+
+namespace chip {
+namespace DeviceLayer {
+
+class ESP32SecureCertDataProvider : public ESP32SecureCertDACProvider, public ESP32FactoryDataProvider
+{
+public:
+    // CommissionableDataProvider implementation
+    CHIP_ERROR GetSetupDiscriminator(uint16_t & setupDiscriminator) override;
+    CHIP_ERROR GetSpake2pIterationCount(uint32_t & iterationCount) override;
+    CHIP_ERROR GetSpake2pSalt(MutableByteSpan & saltBuf) override;
+    CHIP_ERROR GetSpake2pVerifier(MutableByteSpan & verifierBuf, size_t & verifierLen) override;
+
+    // GetRotatingDeviceIdUniqueId from GenericDeviceInstanceInfoProvider
+    CHIP_ERROR GetRotatingDeviceIdUniqueId(MutableByteSpan & uniqueIdSpan) override;
+};
+
+} // namespace DeviceLayer
+} // namespace chip