Update verify.c

This commit is contained in:
DavidXanatos 2021-07-23 19:12:48 +02:00
parent 9dc256a24e
commit d4b4cdd738
1 changed files with 67 additions and 83 deletions

View File

@ -1,3 +1,21 @@
/*
* Copyright 2021 David Xanatos, xanasoft.com
*
* Based on the processhacker's CustomSignTool, Copyright 2016 wj32
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <ntstatus.h> #include <ntstatus.h>
#define WIN32_NO_STATUS #define WIN32_NO_STATUS
@ -36,7 +54,7 @@ static UCHAR KphpTrustedPublicKey[] =
#define FILE_BUFFER_SIZE 4096 #define FILE_BUFFER_SIZE 4096
NTSTATUS PhCreateFileWin32(_Out_ PHANDLE FileHandle, _In_ PCWSTR FileName, _In_ ACCESS_MASK DesiredAccess, static NTSTATUS MyCreateFile(_Out_ PHANDLE FileHandle, _In_ PCWSTR FileName, _In_ ACCESS_MASK DesiredAccess,
_In_opt_ ULONG FileAttributes, _In_ ULONG ShareAccess, _In_ ULONG CreateDisposition, _In_ ULONG CreateOptions) _In_opt_ ULONG FileAttributes, _In_ ULONG ShareAccess, _In_ ULONG CreateDisposition, _In_ ULONG CreateOptions)
{ {
UNICODE_STRING uni; UNICODE_STRING uni;
@ -50,14 +68,6 @@ NTSTATUS PhCreateFileWin32(_Out_ PHANDLE FileHandle, _In_ PCWSTR FileName, _In_
return NtCreateFile(FileHandle, DesiredAccess, &attr, &Iosb, NULL, FileAttributes, ShareAccess, CreateDisposition, CreateOptions, NULL, 0); return NtCreateFile(FileHandle, DesiredAccess, &attr, &Iosb, NULL, FileAttributes, ShareAccess, CreateDisposition, CreateOptions, NULL, 0);
} }
NTSTATUS PhGetFileSize(_In_ HANDLE FileHandle, _Out_ PLARGE_INTEGER Size)
{
if (GetFileSizeEx(FileHandle, Size))
return STATUS_SUCCESS;
return STATUS_UNSUCCESSFUL;
}
static NTSTATUS CstReadFile( static NTSTATUS CstReadFile(
_In_ PWSTR FileName, _In_ PWSTR FileName,
_In_ ULONG FileSizeLimit, _In_ ULONG FileSizeLimit,
@ -71,13 +81,10 @@ static NTSTATUS CstReadFile(
PVOID buffer; PVOID buffer;
IO_STATUS_BLOCK iosb; IO_STATUS_BLOCK iosb;
if (!NT_SUCCESS(status = PhCreateFileWin32(&fileHandle, FileName, FILE_GENERIC_READ, FILE_ATTRIBUTE_NORMAL, FILE_SHARE_READ, FILE_OPEN, FILE_SYNCHRONOUS_IO_NONALERT | FILE_NON_DIRECTORY_FILE))) if (!NT_SUCCESS(status = MyCreateFile(&fileHandle, FileName, FILE_GENERIC_READ, FILE_ATTRIBUTE_NORMAL, FILE_SHARE_READ, FILE_OPEN, FILE_SYNCHRONOUS_IO_NONALERT | FILE_NON_DIRECTORY_FILE)))
goto CleanupExit; goto CleanupExit;
if (!NT_SUCCESS(status = PhGetFileSize(fileHandle, &fileSize))) if (!GetFileSizeEx(fileHandle, &fileSize) || fileSize.QuadPart > FileSizeLimit)
goto CleanupExit;
if (fileSize.QuadPart > FileSizeLimit)
goto CleanupExit; goto CleanupExit;
buffer = malloc((ULONG)fileSize.QuadPart); buffer = malloc((ULONG)fileSize.QuadPart);
@ -95,89 +102,79 @@ CleanupExit:
} }
typedef struct { typedef struct {
BCRYPT_ALG_HANDLE hashAlgHandle; BCRYPT_ALG_HANDLE algHandle;
ULONG hashObjectSize; BCRYPT_HASH_HANDLE handle;
ULONG hashSize; PVOID object;
PVOID hashObject; } MY_HASH_OBJ;
BCRYPT_HASH_HANDLE hashHandle;
} CST_HASH_OBJ;
static VOID CstFreeHash(CST_HASH_OBJ* pHashObj) static VOID MyFreeHash(MY_HASH_OBJ* pHashObj)
{ {
if (pHashObj->hashHandle) if (pHashObj->handle)
BCryptDestroyHash(pHashObj->hashHandle); BCryptDestroyHash(pHashObj->handle);
if (pHashObj->hashObject) if (pHashObj->object)
free(pHashObj->hashObject); // must be freed after destroying hash object free(pHashObj->object);
if (pHashObj->hashAlgHandle) if (pHashObj->algHandle)
BCryptCloseAlgorithmProvider(pHashObj->hashAlgHandle, 0); BCryptCloseAlgorithmProvider(pHashObj->algHandle, 0);
} }
static NTSTATUS CstInitHash(CST_HASH_OBJ* pHashObj) static NTSTATUS MyInitHash(MY_HASH_OBJ* pHashObj)
{ {
NTSTATUS status; NTSTATUS status;
ULONG hashObjectSize;
ULONG querySize; ULONG querySize;
memset(pHashObj, 0, sizeof(CST_HASH_OBJ)); memset(pHashObj, 0, sizeof(MY_HASH_OBJ));
if (!NT_SUCCESS(status = BCryptOpenAlgorithmProvider(&pHashObj->hashAlgHandle, CST_HASH_ALGORITHM, NULL, 0))) if (!NT_SUCCESS(status = BCryptOpenAlgorithmProvider(&pHashObj->algHandle, CST_HASH_ALGORITHM, NULL, 0)))
goto CleanupExit; goto CleanupExit;
if (!NT_SUCCESS(status = BCryptGetProperty(pHashObj->hashAlgHandle, BCRYPT_OBJECT_LENGTH, (PUCHAR)&pHashObj->hashObjectSize, sizeof(ULONG), &querySize, 0))) if (!NT_SUCCESS(status = BCryptGetProperty(pHashObj->algHandle, BCRYPT_OBJECT_LENGTH, (PUCHAR)&hashObjectSize, sizeof(ULONG), &querySize, 0)))
goto CleanupExit; goto CleanupExit;
if (!NT_SUCCESS(status = BCryptGetProperty(pHashObj->hashAlgHandle, BCRYPT_HASH_LENGTH, (PUCHAR)&pHashObj->hashSize, sizeof(ULONG), &querySize, 0))) pHashObj->object = malloc(hashObjectSize);
goto CleanupExit; if (!pHashObj->object) {
pHashObj->hashObject = malloc(pHashObj->hashObjectSize);
if (!pHashObj->hashObject) {
status = STATUS_INSUFFICIENT_RESOURCES; status = STATUS_INSUFFICIENT_RESOURCES;
goto CleanupExit; goto CleanupExit;
} }
if (!NT_SUCCESS(status = BCryptCreateHash(pHashObj->hashAlgHandle, &pHashObj->hashHandle, (PUCHAR)pHashObj->hashObject, pHashObj->hashObjectSize, NULL, 0, 0))) if (!NT_SUCCESS(status = BCryptCreateHash(pHashObj->algHandle, &pHashObj->handle, (PUCHAR)pHashObj->object, hashObjectSize, NULL, 0, 0)))
goto CleanupExit; goto CleanupExit;
CleanupExit: CleanupExit:
if (!NT_SUCCESS(status)) if (!NT_SUCCESS(status))
CstFreeHash(pHashObj); MyFreeHash(pHashObj);
return status; return status;
} }
static NTSTATUS CstHashData( static NTSTATUS MyHashData(MY_HASH_OBJ* pHashObj, PVOID Data, ULONG DataSize)
CST_HASH_OBJ* pHashObj,
_Out_ PVOID Data,
_Out_ ULONG DataSize
)
{ {
return BCryptHashData(pHashObj->hashHandle, (PUCHAR)Data, DataSize, 0); return BCryptHashData(pHashObj->handle, (PUCHAR)Data, DataSize, 0);
} }
static NTSTATUS CstFinishHash( static NTSTATUS MyFinishHash(MY_HASH_OBJ* pHashObj, PVOID* Hash, PULONG HashSize)
CST_HASH_OBJ* pHashObj,
_Out_ PVOID* Hash,
_Out_ PULONG HashSize
)
{ {
NTSTATUS status; NTSTATUS status;
PVOID hash; ULONG querySize;
hash = malloc(pHashObj->hashSize); if (!NT_SUCCESS(status = BCryptGetProperty(pHashObj->algHandle, BCRYPT_HASH_LENGTH, (PUCHAR)HashSize, sizeof(ULONG), &querySize, 0)))
if (!hash) { goto CleanupExit;
*Hash = malloc(*HashSize);
if (!*Hash) {
status = STATUS_INSUFFICIENT_RESOURCES; status = STATUS_INSUFFICIENT_RESOURCES;
goto CleanupExit; goto CleanupExit;
} }
if (!NT_SUCCESS(status = BCryptFinishHash(pHashObj->hashHandle, (PUCHAR)hash, pHashObj->hashSize, 0))) if (!NT_SUCCESS(status = BCryptFinishHash(pHashObj->handle, (PUCHAR)*Hash, *HashSize, 0)))
goto CleanupExit; goto CleanupExit;
*HashSize = pHashObj->hashSize;
*Hash = hash;
return STATUS_SUCCESS; return STATUS_SUCCESS;
CleanupExit: CleanupExit:
if (hash) if (*Hash) {
free(hash); free(*Hash);
*Hash = NULL;
}
return status; return status;
} }
@ -193,12 +190,12 @@ static NTSTATUS CstHashFile(
HANDLE fileHandle = INVALID_HANDLE_VALUE; HANDLE fileHandle = INVALID_HANDLE_VALUE;
PVOID buffer = NULL; PVOID buffer = NULL;
IO_STATUS_BLOCK iosb; IO_STATUS_BLOCK iosb;
CST_HASH_OBJ hashObj; MY_HASH_OBJ hashObj;
if (!NT_SUCCESS(status = CstInitHash(&hashObj))) if (!NT_SUCCESS(status = MyInitHash(&hashObj)))
goto CleanupExit; goto CleanupExit;
if (!NT_SUCCESS(status = PhCreateFileWin32(&fileHandle, FileName, FILE_GENERIC_READ, FILE_ATTRIBUTE_NORMAL, FILE_SHARE_READ, FILE_OPEN, FILE_SYNCHRONOUS_IO_NONALERT | FILE_NON_DIRECTORY_FILE))) if (!NT_SUCCESS(status = MyCreateFile(&fileHandle, FileName, FILE_GENERIC_READ, FILE_ATTRIBUTE_NORMAL, FILE_SHARE_READ, FILE_OPEN, FILE_SYNCHRONOUS_IO_NONALERT | FILE_NON_DIRECTORY_FILE)))
goto CleanupExit; goto CleanupExit;
buffer = malloc(FILE_BUFFER_SIZE); buffer = malloc(FILE_BUFFER_SIZE);
@ -217,11 +214,11 @@ static NTSTATUS CstHashFile(
goto CleanupExit; goto CleanupExit;
} }
if (!NT_SUCCESS(status = CstHashData(&hashObj, buffer, (ULONG)iosb.Information))) if (!NT_SUCCESS(status = MyHashData(&hashObj, buffer, (ULONG)iosb.Information)))
goto CleanupExit; goto CleanupExit;
} }
if (!NT_SUCCESS(status = CstFinishHash(&hashObj, Hash, HashSize))) if (!NT_SUCCESS(status = MyFinishHash(&hashObj, Hash, HashSize)))
goto CleanupExit; goto CleanupExit;
CleanupExit: CleanupExit:
@ -229,39 +226,26 @@ CleanupExit:
free(buffer); free(buffer);
if(fileHandle != INVALID_HANDLE_VALUE) if(fileHandle != INVALID_HANDLE_VALUE)
NtClose(fileHandle); NtClose(fileHandle);
CstFreeHash(&hashObj); MyFreeHash(&hashObj);
return status; return status;
} }
static NTSTATUS VerifyHashSignature( static NTSTATUS VerifyHashSignature(PVOID Hash, ULONG HashSize, PVOID Signature, ULONG SignatureSize)
_In_ PVOID Hash,
_In_ ULONG HashSize,
_In_ PVOID Signature,
_In_ ULONG SignatureSize
)
{ {
NTSTATUS status; NTSTATUS status;
BCRYPT_ALG_HANDLE signAlgHandle = NULL; BCRYPT_ALG_HANDLE signAlgHandle = NULL;
BCRYPT_KEY_HANDLE keyHandle = NULL; BCRYPT_KEY_HANDLE keyHandle = NULL;
// Import the trusted public key.
if (!NT_SUCCESS(status = BCryptOpenAlgorithmProvider(&signAlgHandle, CST_SIGN_ALGORITHM, NULL, 0))) if (!NT_SUCCESS(status = BCryptOpenAlgorithmProvider(&signAlgHandle, CST_SIGN_ALGORITHM, NULL, 0)))
goto CleanupExit; goto CleanupExit;
if (!NT_SUCCESS(status = BCryptImportKeyPair(signAlgHandle, NULL, CST_BLOB_PUBLIC, &keyHandle,
KphpTrustedPublicKey, sizeof(KphpTrustedPublicKey), 0)))
{
goto CleanupExit;
}
// Verify the hash. if (!NT_SUCCESS(status = BCryptImportKeyPair(signAlgHandle, NULL, CST_BLOB_PUBLIC, &keyHandle, KphpTrustedPublicKey, sizeof(KphpTrustedPublicKey), 0)))
goto CleanupExit;
if (!NT_SUCCESS(status = BCryptVerifySignature(keyHandle, NULL, (PUCHAR)Hash, HashSize, (PUCHAR)Signature,
SignatureSize, 0)))
{ if (!NT_SUCCESS(status = BCryptVerifySignature(keyHandle, NULL, (PUCHAR)Hash, HashSize, (PUCHAR)Signature, SignatureSize, 0)))
goto CleanupExit; goto CleanupExit;
}
CleanupExit: CleanupExit:
if (keyHandle != NULL) if (keyHandle != NULL)