blob: 11eab0251931356c61c40ee6d4ef76f6e328a0bc [file] [log] [blame]
/*
* Copyright (c) 2023 Project CHIP Authors
* All rights reserved.
*
* 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.
*/
/**
* @file
* mbedTLS based implementation of CHIP crypto primitives related to certificate
* generation and validation.
*/
#include "CHIPCryptoPAL.h"
#include "CHIPCryptoPALmbedTLS.h"
#include <lib/core/CHIPSafeCasts.h>
#include <lib/support/CodeUtils.h>
#include <lib/support/SafeInt.h>
#include <mbedtls/ecp.h>
#include <mbedtls/oid.h>
#include <mbedtls/x509.h>
#include <mbedtls/x509_csr.h>
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#include <mbedtls/x509_crt.h>
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
namespace chip {
namespace Crypto {
CHIP_ERROR VerifyCertificateSigningRequest(const uint8_t * csr_buf, size_t csr_length, P256PublicKey & pubkey)
{
#if defined(MBEDTLS_X509_CSR_PARSE_C)
ReturnErrorOnFailure(VerifyCertificateSigningRequestFormat(csr_buf, csr_length));
// TODO: For some embedded targets, mbedTLS library doesn't have mbedtls_x509_csr_parse_der, and mbedtls_x509_csr_parse_free.
// Taking a step back, embedded targets likely will not process CSR requests. Adding this action item to reevaluate
// this if there's a need for this processing for embedded targets.
CHIP_ERROR error = CHIP_NO_ERROR;
size_t pubkey_size = 0;
mbedtls_ecp_keypair * keypair = nullptr;
P256ECDSASignature signature;
MutableByteSpan out_raw_sig_span(signature.Bytes(), signature.Capacity());
mbedtls_x509_csr csr;
mbedtls_x509_csr_init(&csr);
int result = mbedtls_x509_csr_parse_der(&csr, csr_buf, csr_length);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
// Verify the signature algorithm and public key type
VerifyOrExit(csr.CHIP_CRYPTO_PAL_PRIVATE(sig_md) == MBEDTLS_MD_SHA256, error = CHIP_ERROR_UNSUPPORTED_SIGNATURE_TYPE);
VerifyOrExit(csr.CHIP_CRYPTO_PAL_PRIVATE(sig_pk) == MBEDTLS_PK_ECDSA, error = CHIP_ERROR_WRONG_KEY_TYPE);
keypair = mbedtls_pk_ec(csr.CHIP_CRYPTO_PAL_PRIVATE_X509(pk));
// Copy the public key from the CSR
result = mbedtls_ecp_point_write_binary(&keypair->CHIP_CRYPTO_PAL_PRIVATE(grp), &keypair->CHIP_CRYPTO_PAL_PRIVATE(Q),
MBEDTLS_ECP_PF_UNCOMPRESSED, &pubkey_size, Uint8::to_uchar(pubkey), pubkey.Length());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
VerifyOrExit(pubkey_size == pubkey.Length(), error = CHIP_ERROR_INTERNAL);
// Convert DER signature to raw signature
error = EcdsaAsn1SignatureToRaw(kP256_FE_Length,
ByteSpan{ csr.CHIP_CRYPTO_PAL_PRIVATE(sig).CHIP_CRYPTO_PAL_PRIVATE_X509(p),
csr.CHIP_CRYPTO_PAL_PRIVATE(sig).CHIP_CRYPTO_PAL_PRIVATE_X509(len) },
out_raw_sig_span);
VerifyOrExit(error == CHIP_NO_ERROR, error = CHIP_ERROR_INVALID_ARGUMENT);
VerifyOrExit(out_raw_sig_span.size() == (kP256_FE_Length * 2), error = CHIP_ERROR_INTERNAL);
signature.SetLength(out_raw_sig_span.size());
// Verify the signature using the public key
error = pubkey.ECDSA_validate_msg_signature(csr.CHIP_CRYPTO_PAL_PRIVATE_X509(cri).CHIP_CRYPTO_PAL_PRIVATE_X509(p),
csr.CHIP_CRYPTO_PAL_PRIVATE_X509(cri).CHIP_CRYPTO_PAL_PRIVATE_X509(len), signature);
SuccessOrExit(error);
exit:
mbedtls_x509_csr_free(&csr);
_log_mbedTLS_error(result);
return error;
#else
ChipLogError(Crypto, "MBEDTLS_X509_CSR_PARSE_C is not enabled. CSR cannot be parsed");
return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
#endif
}
namespace {
#if defined(MBEDTLS_X509_CRT_PARSE_C)
bool IsTimeGreaterThanEqual(const mbedtls_x509_time * const timeA, const mbedtls_x509_time * const timeB)
{
// checks if two values are different and if yes, then returns first > second.
#define RETURN_STRICTLY_GREATER_IF_DIFFERENT(component) \
{ \
auto valueA = timeA->CHIP_CRYPTO_PAL_PRIVATE_X509(component); \
auto valueB = timeB->CHIP_CRYPTO_PAL_PRIVATE_X509(component); \
\
if (valueA != valueB) \
{ \
return valueA > valueB; \
} \
}
RETURN_STRICTLY_GREATER_IF_DIFFERENT(year);
RETURN_STRICTLY_GREATER_IF_DIFFERENT(mon);
RETURN_STRICTLY_GREATER_IF_DIFFERENT(day);
RETURN_STRICTLY_GREATER_IF_DIFFERENT(hour);
RETURN_STRICTLY_GREATER_IF_DIFFERENT(min);
RETURN_STRICTLY_GREATER_IF_DIFFERENT(sec);
// all above are equal
return true;
}
CHIP_ERROR IsCertificateValidAtIssuance(const mbedtls_x509_crt * candidateCertificate, const mbedtls_x509_crt * issuerCertificate)
{
mbedtls_x509_time candidateNotBeforeTime = candidateCertificate->CHIP_CRYPTO_PAL_PRIVATE_X509(valid_from);
mbedtls_x509_time issuerNotBeforeTime = issuerCertificate->CHIP_CRYPTO_PAL_PRIVATE_X509(valid_from);
mbedtls_x509_time issuerNotAfterTime = issuerCertificate->CHIP_CRYPTO_PAL_PRIVATE_X509(valid_to);
// check if candidateCertificate is issued at or after issuerCertificate's notBefore timestamp
VerifyOrReturnError(IsTimeGreaterThanEqual(&candidateNotBeforeTime, &issuerNotBeforeTime), CHIP_ERROR_CERT_EXPIRED);
// check if candidateCertificate is issued at or before issuerCertificate's notAfter timestamp
VerifyOrReturnError(IsTimeGreaterThanEqual(&issuerNotAfterTime, &candidateNotBeforeTime), CHIP_ERROR_CERT_EXPIRED);
return CHIP_NO_ERROR;
}
int CallbackForCustomValidityCheck(void * data, mbedtls_x509_crt * crt, int depth, uint32_t * flags)
{
mbedtls_x509_crt * leafCert = reinterpret_cast<mbedtls_x509_crt *>(data);
mbedtls_x509_crt * issuerCert = crt;
// Ignore any time validy error performed by the standard mbedTLS code.
*flags &= ~(static_cast<uint32_t>(MBEDTLS_X509_BADCERT_EXPIRED | MBEDTLS_X509_BADCERT_FUTURE));
// Verify that the leaf certificate has a notBefore time valid within the validity period of the issuerCertificate.
// Note that this callback is invoked for each certificate in the chain.
if (IsCertificateValidAtIssuance(leafCert, issuerCert) != CHIP_NO_ERROR)
{
return MBEDTLS_ERR_X509_INVALID_DATE;
}
return 0;
}
constexpr uint8_t sOID_AttributeType_CommonName[] = { 0x55, 0x04, 0x03 };
constexpr uint8_t sOID_AttributeType_MatterVendorId[] = { 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0xA2, 0x7C, 0x02, 0x01 };
constexpr uint8_t sOID_AttributeType_MatterProductId[] = { 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0xA2, 0x7C, 0x02, 0x02 };
constexpr uint8_t sOID_SigAlgo_ECDSAWithSHA256[] = { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x03, 0x02 };
constexpr uint8_t sOID_Extension_BasicConstraints[] = { 0x55, 0x1D, 0x13 };
constexpr uint8_t sOID_Extension_KeyUsage[] = { 0x55, 0x1D, 0x0F };
constexpr uint8_t sOID_Extension_SubjectKeyIdentifier[] = { 0x55, 0x1D, 0x0E };
constexpr uint8_t sOID_Extension_AuthorityKeyIdentifier[] = { 0x55, 0x1D, 0x23 };
constexpr uint8_t sOID_Extension_CRLDistributionPoint[] = { 0x55, 0x1D, 0x1F };
/**
* Compares an mbedtls_asn1_buf structure (oidBuf) to a reference OID represented as uint8_t array (oid).
*/
#define OID_CMP(oid, oidBuf) \
((MBEDTLS_ASN1_OID == (oidBuf).CHIP_CRYPTO_PAL_PRIVATE_X509(tag)) && \
(sizeof(oid) == (oidBuf).CHIP_CRYPTO_PAL_PRIVATE_X509(len)) && \
(memcmp((oid), (oidBuf).CHIP_CRYPTO_PAL_PRIVATE_X509(p), (oidBuf).CHIP_CRYPTO_PAL_PRIVATE_X509(len)) == 0))
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
} // anonymous namespace
CHIP_ERROR VerifyAttestationCertificateFormat(const ByteSpan & cert, AttestationCertType certType)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
int result = 0;
mbedtls_x509_crt mbed_cert;
unsigned char * p = nullptr;
const unsigned char * end = nullptr;
size_t len = 0;
bool extBasicPresent = false;
bool extKeyUsagePresent = false;
VerifyOrReturnError(!cert.empty(), CHIP_ERROR_INVALID_ARGUMENT);
mbedtls_x509_crt_init(&mbed_cert);
result = mbedtls_x509_crt_parse(&mbed_cert, Uint8::to_const_uchar(cert.data()), cert.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
// "version" value is 1 higher than the actual encoded value.
VerifyOrExit(mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(version) - 1 == 2, error = CHIP_ERROR_INTERNAL);
// Verify signature algorithms is ECDSA with SHA256.
VerifyOrExit(OID_CMP(sOID_SigAlgo_ECDSAWithSHA256, mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(sig_oid)),
error = CHIP_ERROR_INTERNAL);
// Verify public key presence and format.
{
Crypto::P256PublicKey pubkey;
SuccessOrExit(error = ExtractPubkeyFromX509Cert(cert, pubkey));
}
p = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
end = p + mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
while (p < end)
{
mbedtls_x509_buf extOID = { 0, 0, nullptr };
int extCritical = 0;
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
/* Get extension ID */
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OID);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
extOID.CHIP_CRYPTO_PAL_PRIVATE_X509(tag) = MBEDTLS_ASN1_OID;
extOID.CHIP_CRYPTO_PAL_PRIVATE_X509(len) = len;
extOID.CHIP_CRYPTO_PAL_PRIVATE_X509(p) = p;
p += len;
/* Get optional critical */
result = mbedtls_asn1_get_bool(&p, end, &extCritical);
VerifyOrExit(result == 0 || result == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG, error = CHIP_ERROR_INTERNAL);
/* Data should be octet string type */
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
if (OID_CMP(sOID_Extension_BasicConstraints, extOID))
{
int isCA = 0;
int pathLen = -1;
VerifyOrExit(extCritical, error = CHIP_ERROR_INTERNAL);
extBasicPresent = true;
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
if (len > 0)
{
unsigned char * seqStart = p;
result = mbedtls_asn1_get_bool(&p, end, &isCA);
VerifyOrExit(result == 0 || result == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG, error = CHIP_ERROR_INTERNAL);
// Check if pathLen is there by validating if the cursor didn't get to the end of
// of the internal SEQUENCE for the basic constraints encapsulation.
// Missing pathLen optional tag will leave pathLen == -1 for following checks.
bool hasPathLen = (p != (seqStart + len));
if (hasPathLen)
{
// Extract pathLen value, making sure it's a valid format.
result = mbedtls_asn1_get_int(&p, end, &pathLen);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
}
}
if (certType == AttestationCertType::kDAC)
{
VerifyOrExit(!isCA && pathLen == -1, error = CHIP_ERROR_INTERNAL);
}
else if (certType == AttestationCertType::kPAI)
{
VerifyOrExit(isCA && pathLen == 0, error = CHIP_ERROR_INTERNAL);
}
else
{
// For PAA, pathlen must be absent or equal to 1 (see Matter 1.1 spec 6.2.2.5)
VerifyOrExit(isCA && (pathLen == -1 || pathLen == 1), error = CHIP_ERROR_INTERNAL);
}
}
else if (OID_CMP(sOID_Extension_KeyUsage, extOID))
{
mbedtls_x509_bitstring bs = { 0, 0, nullptr };
unsigned int keyUsage = 0;
VerifyOrExit(extCritical, error = CHIP_ERROR_INTERNAL);
extKeyUsagePresent = true;
result = mbedtls_asn1_get_bitstring(&p, p + len, &bs);
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
for (size_t i = 0; i < bs.CHIP_CRYPTO_PAL_PRIVATE_X509(len) && i < sizeof(unsigned int); i++)
{
keyUsage |= static_cast<unsigned int>(bs.CHIP_CRYPTO_PAL_PRIVATE_X509(p)[i]) << (8 * i);
}
if (certType == AttestationCertType::kDAC)
{
// SHALL only have the digitalSignature bit set.
VerifyOrExit(keyUsage == MBEDTLS_X509_KU_DIGITAL_SIGNATURE, error = CHIP_ERROR_INTERNAL);
}
else
{
bool keyCertSignFlag = keyUsage & MBEDTLS_X509_KU_KEY_CERT_SIGN;
bool crlSignFlag = keyUsage & MBEDTLS_X509_KU_CRL_SIGN;
bool otherFlags = keyUsage &
~static_cast<unsigned int>(MBEDTLS_X509_KU_CRL_SIGN | MBEDTLS_X509_KU_KEY_CERT_SIGN |
MBEDTLS_X509_KU_DIGITAL_SIGNATURE);
VerifyOrExit(keyCertSignFlag && crlSignFlag && !otherFlags, error = CHIP_ERROR_INTERNAL);
}
}
else
{
p += len;
}
}
// Verify basic and key usage extensions are present.
VerifyOrExit(extBasicPresent && extKeyUsagePresent, error = CHIP_ERROR_INTERNAL);
// Verify that SKID and AKID extensions are present.
{
uint8_t kidBuf[kSubjectKeyIdentifierLength];
MutableByteSpan kid(kidBuf);
SuccessOrExit(error = ExtractSKIDFromX509Cert(cert, kid));
if (certType == AttestationCertType::kDAC || certType == AttestationCertType::kPAI)
{
// Mandatory extension for DAC and PAI certs.
SuccessOrExit(error = ExtractAKIDFromX509Cert(cert, kid));
}
}
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbed_cert);
#else
(void) cert;
(void) certType;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
CHIP_ERROR ValidateCertificateChain(const uint8_t * rootCertificate, size_t rootCertificateLen, const uint8_t * caCertificate,
size_t caCertificateLen, const uint8_t * leafCertificate, size_t leafCertificateLen,
CertificateChainValidationResult & result)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
mbedtls_x509_crt certChain;
mbedtls_x509_crt rootCert;
int mbedResult;
uint32_t flags = 0;
result = CertificateChainValidationResult::kInternalFrameworkError;
VerifyOrReturnError(rootCertificate != nullptr && rootCertificateLen != 0,
(result = CertificateChainValidationResult::kRootArgumentInvalid, CHIP_ERROR_INVALID_ARGUMENT));
VerifyOrReturnError(leafCertificate != nullptr && leafCertificateLen != 0,
(result = CertificateChainValidationResult::kLeafArgumentInvalid, CHIP_ERROR_INVALID_ARGUMENT));
mbedtls_x509_crt_init(&certChain);
mbedtls_x509_crt_init(&rootCert);
/* Start of chain */
mbedResult = mbedtls_x509_crt_parse(&certChain, Uint8::to_const_uchar(leafCertificate), leafCertificateLen);
VerifyOrExit(mbedResult == 0, (result = CertificateChainValidationResult::kLeafFormatInvalid, error = CHIP_ERROR_INTERNAL));
/* Add the intermediate to the chain, if present */
if (caCertificate != nullptr && caCertificateLen > 0)
{
mbedResult = mbedtls_x509_crt_parse(&certChain, Uint8::to_const_uchar(caCertificate), caCertificateLen);
VerifyOrExit(mbedResult == 0, (result = CertificateChainValidationResult::kICAFormatInvalid, error = CHIP_ERROR_INTERNAL));
}
/* Parse the root cert */
mbedResult = mbedtls_x509_crt_parse(&rootCert, Uint8::to_const_uchar(rootCertificate), rootCertificateLen);
VerifyOrExit(mbedResult == 0, (result = CertificateChainValidationResult::kRootFormatInvalid, error = CHIP_ERROR_INTERNAL));
/* Verify the chain against the root */
mbedResult =
mbedtls_x509_crt_verify(&certChain, &rootCert, nullptr, nullptr, &flags, CallbackForCustomValidityCheck, &certChain);
switch (mbedResult)
{
case 0:
VerifyOrExit(flags == 0, (result = CertificateChainValidationResult::kInternalFrameworkError, error = CHIP_ERROR_INTERNAL));
result = CertificateChainValidationResult::kSuccess;
break;
case MBEDTLS_ERR_X509_INVALID_DATE:
case MBEDTLS_ERR_X509_CERT_VERIFY_FAILED:
result = CertificateChainValidationResult::kChainInvalid;
error = CHIP_ERROR_CERT_NOT_TRUSTED;
break;
default:
result = CertificateChainValidationResult::kInternalFrameworkError;
error = CHIP_ERROR_INTERNAL;
break;
}
exit:
_log_mbedTLS_error(mbedResult);
mbedtls_x509_crt_free(&certChain);
mbedtls_x509_crt_free(&rootCert);
#else
(void) rootCertificate;
(void) rootCertificateLen;
(void) caCertificate;
(void) caCertificateLen;
(void) leafCertificate;
(void) leafCertificateLen;
(void) result;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
CHIP_ERROR IsCertificateValidAtIssuance(const ByteSpan & candidateCertificate, const ByteSpan & issuerCertificate)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
mbedtls_x509_crt mbedCandidateCertificate;
mbedtls_x509_crt mbedIssuerCertificate;
int result;
VerifyOrReturnError(!candidateCertificate.empty() && !issuerCertificate.empty(), CHIP_ERROR_INVALID_ARGUMENT);
mbedtls_x509_crt_init(&mbedCandidateCertificate);
mbedtls_x509_crt_init(&mbedIssuerCertificate);
result = mbedtls_x509_crt_parse(&mbedCandidateCertificate, Uint8::to_const_uchar(candidateCertificate.data()),
candidateCertificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
result =
mbedtls_x509_crt_parse(&mbedIssuerCertificate, Uint8::to_const_uchar(issuerCertificate.data()), issuerCertificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
// Verify that the candidateCertificate has a notBefore time valid within the validity period of the issuerCertificate.
SuccessOrExit(error = IsCertificateValidAtIssuance(&mbedCandidateCertificate, &mbedIssuerCertificate));
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbedCandidateCertificate);
mbedtls_x509_crt_free(&mbedIssuerCertificate);
#else
(void) candidateCertificate;
(void) issuerCertificate;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
CHIP_ERROR IsCertificateValidAtCurrentTime(const ByteSpan & certificate)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
mbedtls_x509_crt mbedCertificate;
int result;
VerifyOrReturnError(!certificate.empty(), CHIP_ERROR_INVALID_ARGUMENT);
mbedtls_x509_crt_init(&mbedCertificate);
result = mbedtls_x509_crt_parse(&mbedCertificate, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
// check if certificate's notBefore timestamp is earlier than or equal to current time.
result = mbedtls_x509_time_is_past(&mbedCertificate.CHIP_CRYPTO_PAL_PRIVATE_X509(valid_from));
VerifyOrExit(result == 1, error = CHIP_ERROR_CERT_EXPIRED);
// check if certificate's notAfter timestamp is later than current time.
result = mbedtls_x509_time_is_future(&mbedCertificate.CHIP_CRYPTO_PAL_PRIVATE_X509(valid_to));
VerifyOrExit(result == 1, error = CHIP_ERROR_CERT_EXPIRED);
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbedCertificate);
#else
(void) certificate;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
CHIP_ERROR ExtractPubkeyFromX509Cert(const ByteSpan & certificate, Crypto::P256PublicKey & pubkey)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
mbedtls_x509_crt mbed_cert;
mbedtls_ecp_keypair * keypair = nullptr;
size_t pubkey_size = 0;
mbedtls_x509_crt_init(&mbed_cert);
int result = mbedtls_x509_crt_parse(&mbed_cert, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
VerifyOrExit(mbedtls_pk_get_type(&(mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(pk))) == MBEDTLS_PK_ECKEY,
error = CHIP_ERROR_INVALID_ARGUMENT);
keypair = mbedtls_pk_ec(mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(pk));
VerifyOrExit(keypair->CHIP_CRYPTO_PAL_PRIVATE(grp).id == MapECPGroupId(pubkey.Type()), error = CHIP_ERROR_INVALID_ARGUMENT);
// Copy the public key from the cert in raw point format
result =
mbedtls_ecp_point_write_binary(&keypair->CHIP_CRYPTO_PAL_PRIVATE(grp), &keypair->CHIP_CRYPTO_PAL_PRIVATE(Q),
MBEDTLS_ECP_PF_UNCOMPRESSED, &pubkey_size, Uint8::to_uchar(pubkey.Bytes()), pubkey.Length());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
VerifyOrExit(pubkey_size == pubkey.Length(), error = CHIP_ERROR_INTERNAL);
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbed_cert);
#else
(void) certificate;
(void) pubkey;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
namespace {
CHIP_ERROR ExtractKIDFromX509Cert(bool extractSKID, const ByteSpan & certificate, MutableByteSpan & kid)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_ERROR_NOT_FOUND;
mbedtls_x509_crt mbed_cert;
unsigned char * p = nullptr;
const unsigned char * end = nullptr;
size_t len = 0;
mbedtls_x509_crt_init(&mbed_cert);
int result = mbedtls_x509_crt_parse(&mbed_cert, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
// TODO: The mbedTLS team is working on supporting SKID and AKID extensions processing.
// Once it is supported, this code should be updated.
p = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
end = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(p) +
mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
while (p < end)
{
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OID);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
mbedtls_x509_buf extOID = { MBEDTLS_ASN1_OID, len, p };
bool extractCurrentExtSKID = extractSKID && OID_CMP(sOID_Extension_SubjectKeyIdentifier, extOID);
bool extractCurrentExtAKID = !extractSKID && OID_CMP(sOID_Extension_AuthorityKeyIdentifier, extOID);
p += len;
int is_critical = 0;
result = mbedtls_asn1_get_bool(&p, end, &is_critical);
VerifyOrExit(result == 0 || result == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG, error = CHIP_ERROR_WRONG_CERT_TYPE);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
if (extractCurrentExtSKID || extractCurrentExtAKID)
{
if (extractCurrentExtSKID)
{
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
}
else
{
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
// Other optional fields, authorityCertIssuer and authorityCertSerialNumber,
// will be skipped if present.
}
VerifyOrExit(len == kSubjectKeyIdentifierLength, error = CHIP_ERROR_WRONG_CERT_TYPE);
VerifyOrExit(len <= kid.size(), error = CHIP_ERROR_BUFFER_TOO_SMALL);
memcpy(kid.data(), p, len);
if (kid.size() > len)
{
kid.reduce_size(len);
}
ExitNow(error = CHIP_NO_ERROR);
break;
}
p += len;
}
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbed_cert);
#else
(void) certificate;
(void) kid;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
} // namespace
CHIP_ERROR ExtractSKIDFromX509Cert(const ByteSpan & certificate, MutableByteSpan & skid)
{
return ExtractKIDFromX509Cert(true, certificate, skid);
}
CHIP_ERROR ExtractAKIDFromX509Cert(const ByteSpan & certificate, MutableByteSpan & akid)
{
return ExtractKIDFromX509Cert(false, certificate, akid);
}
CHIP_ERROR ExtractCRLDistributionPointURIFromX509Cert(const ByteSpan & certificate, MutableCharSpan & cdpurl)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_ERROR_NOT_FOUND;
mbedtls_x509_crt mbed_cert;
unsigned char * p = nullptr;
const unsigned char * end = nullptr;
size_t len = 0;
size_t cdpExtCount = 0;
VerifyOrReturnError(!certificate.empty() && CanCastTo<long>(certificate.size()), CHIP_ERROR_INVALID_ARGUMENT);
mbedtls_x509_crt_init(&mbed_cert);
int result = mbedtls_x509_crt_parse(&mbed_cert, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
p = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
end = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(p) +
mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
while (p < end)
{
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OID);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
mbedtls_x509_buf extOID = { MBEDTLS_ASN1_OID, len, p };
bool isCurrentExtCDP = OID_CMP(sOID_Extension_CRLDistributionPoint, extOID);
p += len;
int is_critical = 0;
result = mbedtls_asn1_get_bool(&p, end, &is_critical);
VerifyOrExit(result == 0 || result == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG, error = CHIP_ERROR_WRONG_CERT_TYPE);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
unsigned char * end_of_ext = p + len;
if (isCurrentExtCDP)
{
// Only one CRL Distribution Point Extension is allowed.
cdpExtCount++;
VerifyOrExit(cdpExtCount <= 1, error = CHIP_ERROR_NOT_FOUND);
// CRL Distribution Point Extension is encoded as a sequence of DistributionPoint:
// CRLDistributionPoints ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint
//
// This implementation only supports a single DistributionPoint (sequence of size 1),
// which is verified by comparing (p + len == end_of_ext)
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
VerifyOrExit(p + len == end_of_ext, error = CHIP_ERROR_NOT_FOUND);
// The DistributionPoint is a sequence of three optional elements:
// DistributionPoint ::= SEQUENCE {
// distributionPoint [0] DistributionPointName OPTIONAL,
// reasons [1] ReasonFlags OPTIONAL,
// cRLIssuer [2] GeneralNames OPTIONAL }
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
VerifyOrExit(p + len == end_of_ext, error = CHIP_ERROR_NOT_FOUND);
// The DistributionPointName is:
// DistributionPointName ::= CHOICE {
// fullName [0] GeneralNames,
// nameRelativeToCRLIssuer [1] RelativeDistinguishedName }
//
// The URI should be encoded in the fullName element.
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
// GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
unsigned char * end_of_general_names = p + len;
// The CDP URI is encoded as a uniformResourceIdentifier field of the GeneralName:
// GeneralName ::= CHOICE {
// otherName [0] OtherName,
// rfc822Name [1] IA5String,
// dNSName [2] IA5String,
// x400Address [3] ORAddress,
// directoryName [4] Name,
// ediPartyName [5] EDIPartyName,
// uniformResourceIdentifier [6] IA5String,
// iPAddress [7] OCTET STRING,
// registeredID [8] OBJECT IDENTIFIER }
result =
mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
// Only single URI instance in the GeneralNames is supported
VerifyOrExit(p + len == end_of_general_names, error = CHIP_ERROR_NOT_FOUND);
const char * urlptr = reinterpret_cast<const char *>(p);
VerifyOrExit((len > strlen(kValidCDPURIHttpPrefix) &&
strncmp(urlptr, kValidCDPURIHttpPrefix, strlen(kValidCDPURIHttpPrefix)) == 0) ||
(len > strlen(kValidCDPURIHttpsPrefix) &&
strncmp(urlptr, kValidCDPURIHttpsPrefix, strlen(kValidCDPURIHttpsPrefix)) == 0),
error = CHIP_ERROR_NOT_FOUND);
error = CopyCharSpanToMutableCharSpan(CharSpan(urlptr, len), cdpurl);
SuccessOrExit(error);
}
p = end_of_ext;
}
VerifyOrExit(cdpExtCount == 1, error = CHIP_ERROR_NOT_FOUND);
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbed_cert);
#else
(void) certificate;
(void) cdpurl;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
CHIP_ERROR ExtractCDPExtensionCRLIssuerFromX509Cert(const ByteSpan & certificate, MutableByteSpan & crlIssuer)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_ERROR_NOT_FOUND;
mbedtls_x509_crt mbed_cert;
unsigned char * p = nullptr;
const unsigned char * end = nullptr;
size_t len = 0;
size_t cdpExtCount = 0;
VerifyOrReturnError(!certificate.empty() && CanCastTo<long>(certificate.size()), CHIP_ERROR_INVALID_ARGUMENT);
mbedtls_x509_crt_init(&mbed_cert);
int result = mbedtls_x509_crt_parse(&mbed_cert, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
p = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
end = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(p) +
mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(v3_ext).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
while (p < end)
{
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OID);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
mbedtls_x509_buf extOID = { MBEDTLS_ASN1_OID, len, p };
bool isCurrentExtCDP = OID_CMP(sOID_Extension_CRLDistributionPoint, extOID);
p += len;
int is_critical = 0;
result = mbedtls_asn1_get_bool(&p, end, &is_critical);
VerifyOrExit(result == 0 || result == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG, error = CHIP_ERROR_WRONG_CERT_TYPE);
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING);
VerifyOrExit(result == 0, error = CHIP_ERROR_WRONG_CERT_TYPE);
unsigned char * end_of_ext = p + len;
if (isCurrentExtCDP)
{
// Only one CRL Distribution Point Extension is allowed.
cdpExtCount++;
VerifyOrExit(cdpExtCount <= 1, error = CHIP_ERROR_NOT_FOUND);
// CRL Distribution Point Extension is encoded as a sequence of DistributionPoint:
// CRLDistributionPoints ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint
//
// This implementation only supports a single DistributionPoint (sequence of size 1),
// which is verified by comparing (p + len == end_of_ext)
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
VerifyOrExit(p + len == end_of_ext, error = CHIP_ERROR_NOT_FOUND);
// The DistributionPoint is a sequence of three optional elements:
// DistributionPoint ::= SEQUENCE {
// distributionPoint [0] DistributionPointName OPTIONAL,
// reasons [1] ReasonFlags OPTIONAL,
// cRLIssuer [2] GeneralNames OPTIONAL }
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
VerifyOrExit(p + len == end_of_ext, error = CHIP_ERROR_NOT_FOUND);
// If distributionPoint element presents, ignore it
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0);
if (result == 0)
{
p += len;
VerifyOrExit(p < end_of_ext, error = CHIP_ERROR_NOT_FOUND);
}
// Check if cRLIssuer element present
result = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 2);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
// The CRL Issuer is encoded as a directoryName field of the GeneralName:
// GeneralName ::= CHOICE {
// otherName [0] OtherName,
// rfc822Name [1] IA5String,
// dNSName [2] IA5String,
// x400Address [3] ORAddress,
// directoryName [4] Name,
// ediPartyName [5] EDIPartyName,
// uniformResourceIdentifier [6] IA5String,
// iPAddress [7] OCTET STRING,
// registeredID [8] OBJECT IDENTIFIER }
result = mbedtls_asn1_get_tag(
&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_X509_SAN_DIRECTORY_NAME);
VerifyOrExit(result == 0, error = CHIP_ERROR_NOT_FOUND);
VerifyOrExit(p + len == end_of_ext, error = CHIP_ERROR_NOT_FOUND);
error = CopySpanToMutableSpan(ByteSpan(p, len), crlIssuer);
SuccessOrExit(error);
}
p = end_of_ext;
}
VerifyOrExit(cdpExtCount == 1, error = CHIP_ERROR_NOT_FOUND);
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbed_cert);
#else
(void) certificate;
(void) crlIssuer;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
CHIP_ERROR ExtractSerialNumberFromX509Cert(const ByteSpan & certificate, MutableByteSpan & serialNumber)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
int result = 0;
uint8_t * p = nullptr;
size_t len = 0;
mbedtls_x509_crt mbed_cert;
mbedtls_x509_crt_init(&mbed_cert);
result = mbedtls_x509_crt_parse(&mbed_cert, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
p = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(serial).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
len = mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(serial).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
VerifyOrExit(len <= serialNumber.size(), error = CHIP_ERROR_BUFFER_TOO_SMALL);
memcpy(serialNumber.data(), p, len);
serialNumber.reduce_size(len);
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbed_cert);
#else
(void) certificate;
(void) serialNumber;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
CHIP_ERROR ExtractVIDPIDFromX509Cert(const ByteSpan & certificate, AttestationCertVidPid & vidpid)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
mbedtls_x509_crt mbed_cert;
mbedtls_asn1_named_data * dnIterator = nullptr;
AttestationCertVidPid vidpidFromCN;
mbedtls_x509_crt_init(&mbed_cert);
int result = mbedtls_x509_crt_parse(&mbed_cert, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
for (dnIterator = &mbed_cert.CHIP_CRYPTO_PAL_PRIVATE_X509(subject); dnIterator != nullptr;
dnIterator = dnIterator->CHIP_CRYPTO_PAL_PRIVATE_X509(next))
{
DNAttrType attrType = DNAttrType::kUnspecified;
if (OID_CMP(sOID_AttributeType_CommonName, dnIterator->CHIP_CRYPTO_PAL_PRIVATE_X509(oid)))
{
attrType = DNAttrType::kCommonName;
}
else if (OID_CMP(sOID_AttributeType_MatterVendorId, dnIterator->CHIP_CRYPTO_PAL_PRIVATE_X509(oid)))
{
attrType = DNAttrType::kMatterVID;
}
else if (OID_CMP(sOID_AttributeType_MatterProductId, dnIterator->CHIP_CRYPTO_PAL_PRIVATE_X509(oid)))
{
attrType = DNAttrType::kMatterPID;
}
size_t val_len = dnIterator->CHIP_CRYPTO_PAL_PRIVATE_X509(val).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
uint8_t * val_p = dnIterator->CHIP_CRYPTO_PAL_PRIVATE_X509(val).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
error = ExtractVIDPIDFromAttributeString(attrType, ByteSpan(val_p, val_len), vidpid, vidpidFromCN);
SuccessOrExit(error);
}
// If Matter Attributes were not found use values extracted from the CN Attribute,
// which might be uninitialized as well.
if (!vidpid.Initialized())
{
vidpid = vidpidFromCN;
}
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbed_cert);
#else
(void) certificate;
(void) vidpid;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
namespace {
CHIP_ERROR ExtractRawDNFromX509Cert(bool extractSubject, const ByteSpan & certificate, MutableByteSpan & dn)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
CHIP_ERROR error = CHIP_NO_ERROR;
int result = 0;
uint8_t * p = nullptr;
size_t len = 0;
mbedtls_x509_crt mbedCertificate;
ReturnErrorCodeIf(certificate.empty(), CHIP_ERROR_INVALID_ARGUMENT);
mbedtls_x509_crt_init(&mbedCertificate);
result = mbedtls_x509_crt_parse(&mbedCertificate, Uint8::to_const_uchar(certificate.data()), certificate.size());
VerifyOrExit(result == 0, error = CHIP_ERROR_INTERNAL);
if (extractSubject)
{
len = mbedCertificate.CHIP_CRYPTO_PAL_PRIVATE_X509(subject_raw).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
p = mbedCertificate.CHIP_CRYPTO_PAL_PRIVATE_X509(subject_raw).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
}
else
{
len = mbedCertificate.CHIP_CRYPTO_PAL_PRIVATE_X509(issuer_raw).CHIP_CRYPTO_PAL_PRIVATE_X509(len);
p = mbedCertificate.CHIP_CRYPTO_PAL_PRIVATE_X509(issuer_raw).CHIP_CRYPTO_PAL_PRIVATE_X509(p);
}
VerifyOrExit(len <= dn.size(), error = CHIP_ERROR_BUFFER_TOO_SMALL);
memcpy(dn.data(), p, len);
dn.reduce_size(len);
exit:
_log_mbedTLS_error(result);
mbedtls_x509_crt_free(&mbedCertificate);
#else
(void) certificate;
(void) dn;
CHIP_ERROR error = CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
return error;
}
} // namespace
CHIP_ERROR ExtractSubjectFromX509Cert(const ByteSpan & certificate, MutableByteSpan & subject)
{
return ExtractRawDNFromX509Cert(true, certificate, subject);
}
CHIP_ERROR ExtractIssuerFromX509Cert(const ByteSpan & certificate, MutableByteSpan & issuer)
{
return ExtractRawDNFromX509Cert(false, certificate, issuer);
}
CHIP_ERROR ReplaceCertIfResignedCertFound(const ByteSpan & referenceCertificate, const ByteSpan * candidateCertificates,
size_t candidateCertificatesCount, ByteSpan & outCertificate)
{
#if defined(MBEDTLS_X509_CRT_PARSE_C)
uint8_t referenceSubjectBuf[kMaxCertificateDistinguishedNameLength];
uint8_t referenceSKIDBuf[kSubjectKeyIdentifierLength];
MutableByteSpan referenceSubject(referenceSubjectBuf);
MutableByteSpan referenceSKID(referenceSKIDBuf);
outCertificate = referenceCertificate;
ReturnErrorCodeIf(candidateCertificates == nullptr || candidateCertificatesCount == 0, CHIP_NO_ERROR);
ReturnErrorOnFailure(ExtractSubjectFromX509Cert(referenceCertificate, referenceSubject));
ReturnErrorOnFailure(ExtractSKIDFromX509Cert(referenceCertificate, referenceSKID));
for (size_t i = 0; i < candidateCertificatesCount; i++)
{
const ByteSpan candidateCertificate = candidateCertificates[i];
uint8_t candidateSubjectBuf[kMaxCertificateDistinguishedNameLength];
uint8_t candidateSKIDBuf[kSubjectKeyIdentifierLength];
MutableByteSpan candidateSubject(candidateSubjectBuf);
MutableByteSpan candidateSKID(candidateSKIDBuf);
ReturnErrorOnFailure(ExtractSubjectFromX509Cert(candidateCertificate, candidateSubject));
ReturnErrorOnFailure(ExtractSKIDFromX509Cert(candidateCertificate, candidateSKID));
if (referenceSKID.data_equal(candidateSKID) && referenceSubject.data_equal(candidateSubject))
{
outCertificate = candidateCertificate;
return CHIP_NO_ERROR;
}
}
return CHIP_NO_ERROR;
#else
(void) referenceCertificate;
(void) candidateCertificates;
(void) candidateCertificatesCount;
(void) outCertificate;
return CHIP_ERROR_NOT_IMPLEMENTED;
#endif // defined(MBEDTLS_X509_CRT_PARSE_C)
}
} // namespace Crypto
} // namespace chip