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zynqmp: Fix -verify header signature checking on non-FSBL ACs #48

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zynqmp: Fix -verify header signature checking on non-FSBL ACs #48

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1 change: 1 addition & 0 deletions zynqmp/include/readimage-zynqmp.h
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Original file line number Diff line number Diff line change
Expand Up @@ -75,6 +75,7 @@ class ZynqMpReadImage : public ReadImage
void VerifyAuthentication(bool);
void VerifyHeaderTableSignature();
void VerifySPKSignature(AuthCertificate4096Structure * auth_cert);
void VerifyBootHeaderSignature(FILE * binFile, AuthCertificate4096Structure * auth_cert);
void VerifyPartitionSignature(void);
bool VerifySignature(bool nist, uint8_t * data, size_t dataLength, ACKey4096 * acKey, uint8_t * signature);

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73 changes: 45 additions & 28 deletions zynqmp/src/verifyimage-zynqmp.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -189,6 +189,9 @@ void ZynqMpReadImage::VerifyHeaderTableSignature()

AuthCertificate4096Structure* auth_cert = (AuthCertificate4096Structure*)(aCs.front());

/* Verifying Header AC Boot Header Signature */
VerifyBootHeaderSignature(binFile, auth_cert);

/* Verifying Header SPK Signature */
VerifySPKSignature(auth_cert);

Expand Down Expand Up @@ -269,6 +272,45 @@ void ZynqMpReadImage::VerifySPKSignature(AuthCertificate4096Structure* auth_cert
}


/*******************************************************************************/
void ZynqMpReadImage::VerifyBootHeaderSignature(FILE* binFile, AuthCertificate4096Structure* auth_cert)
{
size_t result;
uint32_t bHLength = sizeof(ZynqMpBootHeaderStructure) + sizeof(RegisterInitTable);
if (bH->fsblAttributes & 0xC0)
{
bHLength += PUF_DATA_LENGTH;
}

auto tempBHBuffer = std::make_unique<uint8_t[]>(bHLength);
if (!(fseek(binFile, 0, SEEK_SET)))
{
result = fread(tempBHBuffer.get(), 1, bHLength, binFile);
if (result != bHLength)
{
LOG_ERROR("Error reading boot header while verifying ");
}
}
else
{
LOG_ERROR("Error seeking to boot header while verifying");
}

bool signatureVerified = VerifySignature(false, tempBHBuffer.get(), bHLength, &auth_cert->acSpk, (unsigned char*)(&auth_cert->acBhSignature));
if (signatureVerified)
{
LOG_MSG(" BootHeader Signature Verified");
}
else
{
LOG_MSG(" BootHeader Signature Verification Failed");
authenticationVerified = false;
LOG_ERROR("Authentication verification failed on bootimage %s", binFilename.c_str());
}
// Cleanup handled by unique_ptr
}


/*******************************************************************************/
void ZynqMpReadImage::VerifyPartitionSignature(void)
{
Expand All @@ -293,35 +335,10 @@ void ZynqMpReadImage::VerifyPartitionSignature(void)

bool checkLoadAddrInBhAndPht = ((*partitionHdr)->destinationExecAddress == bH->fsblExecAddress);
bool isItBootloader = (checkLoadAddrInBhAndPht && (bH->sourceOffset != 0));

if (isItBootloader)
{
uint32_t bHLength = sizeof(ZynqMpBootHeaderStructure) + sizeof(RegisterInitTable);
if (bH->fsblAttributes & 0xC0)
{
bHLength += PUF_DATA_LENGTH;
}

auto tempBHBuffer = std::make_unique<uint8_t[]>(bHLength);
size_t result = fread(tempBHBuffer.get(), 1, bHLength, binFile);
if (result != bHLength)
{
LOG_ERROR("Error reading boot header while verifying ");
}

bool signatureVerified = VerifySignature(false, tempBHBuffer.get(), bHLength, &auth_cert->acSpk, (unsigned char*)(&auth_cert->acBhSignature));
if (signatureVerified)
{
LOG_MSG(" BootHeader Signature Verified");
}
else
{
LOG_MSG(" BootHeader Signature Verification Failed");
authenticationVerified = false;
LOG_ERROR("Authentication verification failed on bootimage %s", binFilename.c_str());
}
// tempBHBuffer is now unique_ptr, automatically deleted
}
/* Verifying each boot header with that AC's own secondary key.
For a multi-block partition only the first block's AC is checked. */
VerifyBootHeaderSignature(binFile, auth_cert);

/* Verifying Partition SPK Signature */
VerifySPKSignature(auth_cert);
Expand Down