system76-edk2/NetworkPkg/TlsDxe/TlsImpl.c

/** @file
  The Miscellaneous Routines for TlsDxe driver.

Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>

This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution.  The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "TlsImpl.h"

/**
  Encrypt the message listed in fragment.

  @param[in]       TlsInstance    The pointer to the TLS instance.
  @param[in, out]  FragmentTable  Pointer to a list of fragment.
                                  On input these fragments contain the TLS header and
                                  plain text TLS payload;
                                  On output these fragments contain the TLS header and
                                  cipher text TLS payload.
  @param[in]       FragmentCount  Number of fragment.

  @retval EFI_SUCCESS             The operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES    Can't allocate memory resources.
  @retval EFI_ABORTED             TLS session state is incorrect.
  @retval Others                  Other errors as indicated.
**/
EFI_STATUS
TlsEncryptPacket (
  IN     TLS_INSTANCE                  *TlsInstance,
  IN OUT EFI_TLS_FRAGMENT_DATA         **FragmentTable,
  IN     UINT32                        *FragmentCount
  )
{
  EFI_STATUS          Status;
  UINTN               Index;
  UINT32              BytesCopied;
  UINT32              BufferInSize;
  UINT8               *BufferIn;
  UINT8               *BufferInPtr;
  TLS_RECORD_HEADER   *RecordHeaderIn;
  UINT16              ThisPlainMessageSize;
  TLS_RECORD_HEADER   *TempRecordHeader;
  UINT16              ThisMessageSize;
  UINT32              BufferOutSize;
  UINT8               *BufferOut;
  INTN                Ret;
  
  Status           = EFI_SUCCESS;
  BytesCopied      = 0;
  BufferInSize     = 0;
  BufferIn         = NULL;
  BufferInPtr      = NULL;
  RecordHeaderIn   = NULL;
  TempRecordHeader = NULL;
  BufferOutSize    = 0;
  BufferOut        = NULL;
  Ret              = 0;

  //
  // Calculate the size according to the fragment table.
  //
  for (Index = 0; Index < *FragmentCount; Index++) {
    BufferInSize += (*FragmentTable)[Index].FragmentLength;
  }

  //
  // Allocate buffer for processing data.
  //
  BufferIn = AllocateZeroPool (BufferInSize);
  if (BufferIn == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto ERROR;
  }

  //
  // Copy all TLS plain record header and payload into BufferIn.
  //
  for (Index = 0; Index < *FragmentCount; Index++) {
    CopyMem (
      (BufferIn + BytesCopied),
      (*FragmentTable)[Index].FragmentBuffer,
      (*FragmentTable)[Index].FragmentLength
      );
    BytesCopied += (*FragmentTable)[Index].FragmentLength;
  }

  BufferOut = AllocateZeroPool (MAX_BUFFER_SIZE);
  if (BufferOut == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto ERROR;
  }

  //
  // Parsing buffer.
  //
  BufferInPtr = BufferIn;
  TempRecordHeader = (TLS_RECORD_HEADER *) BufferOut;
  while ((UINTN) BufferInPtr < (UINTN) BufferIn + BufferInSize) {
    RecordHeaderIn = (TLS_RECORD_HEADER *) BufferInPtr;
    
    if (RecordHeaderIn->ContentType != TLS_CONTENT_TYPE_APPLICATION_DATA) {
      Status = EFI_INVALID_PARAMETER;
      goto ERROR;
    }
    
    ThisPlainMessageSize = RecordHeaderIn->Length;

    TlsWrite (TlsInstance->TlsConn, (UINT8 *) (RecordHeaderIn + 1), ThisPlainMessageSize);
    
    Ret = TlsCtrlTrafficOut (TlsInstance->TlsConn, (UINT8 *)(TempRecordHeader), MAX_BUFFER_SIZE - BufferOutSize);

    if (Ret > 0) {
      ThisMessageSize = (UINT16) Ret;
    } else {
      //
      // No data was successfully encrypted, continue to encrypt other messages.
      //
      DEBUG ((EFI_D_WARN, "TlsEncryptPacket: No data read from TLS object.\n"));
    
      ThisMessageSize = 0;
    }

    BufferOutSize += ThisMessageSize;

    BufferInPtr += RECORD_HEADER_LEN + ThisPlainMessageSize;
    TempRecordHeader += ThisMessageSize;
  }

  FreePool (BufferIn);
  BufferIn = NULL;

  //
  // The caller will be responsible to handle the original fragment table.
  //
  *FragmentTable = AllocateZeroPool (sizeof (EFI_TLS_FRAGMENT_DATA));
  if (*FragmentTable == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto ERROR;
  }

  (*FragmentTable)[0].FragmentBuffer  = BufferOut;
  (*FragmentTable)[0].FragmentLength  = BufferOutSize;
  *FragmentCount                      = 1;

  return Status;

ERROR:
  
  if (BufferIn != NULL) {
    FreePool (BufferIn);
    BufferIn = NULL;
  }

  if (BufferOut != NULL) {
    FreePool (BufferOut);
    BufferOut = NULL;
  }
  
  return Status;
}

/**
  Decrypt the message listed in fragment.

  @param[in]       TlsInstance    The pointer to the TLS instance.
  @param[in, out]  FragmentTable  Pointer to a list of fragment.
                                  On input these fragments contain the TLS header and
                                  cipher text TLS payload;
                                  On output these fragments contain the TLS header and
                                  plain text TLS payload.
  @param[in]       FragmentCount  Number of fragment.

  @retval EFI_SUCCESS             The operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES    Can't allocate memory resources.
  @retval EFI_ABORTED             TLS session state is incorrect.
  @retval Others                  Other errors as indicated.
**/
EFI_STATUS
TlsDecryptPacket (
  IN     TLS_INSTANCE                  *TlsInstance,
  IN OUT EFI_TLS_FRAGMENT_DATA         **FragmentTable,
  IN     UINT32                        *FragmentCount
  )
{
  EFI_STATUS          Status;
  UINTN               Index;
  UINT32              BytesCopied;
  UINT8               *BufferIn;
  UINT32              BufferInSize;
  UINT8               *BufferInPtr;
  TLS_RECORD_HEADER   *RecordHeaderIn;
  UINT16              ThisCipherMessageSize;
  TLS_RECORD_HEADER   *TempRecordHeader;
  UINT16              ThisPlainMessageSize;
  UINT8               *BufferOut;
  UINT32              BufferOutSize;
  INTN                Ret;

  Status           = EFI_SUCCESS;
  BytesCopied      = 0;
  BufferIn         = NULL;
  BufferInSize     = 0;
  BufferInPtr      = NULL;
  RecordHeaderIn   = NULL;
  TempRecordHeader = NULL;
  BufferOut        = NULL;
  BufferOutSize    = 0;
  Ret              = 0;

  //
  // Calculate the size according to the fragment table.
  //
  for (Index = 0; Index < *FragmentCount; Index++) {
    BufferInSize += (*FragmentTable)[Index].FragmentLength;
  }

  //
  // Allocate buffer for processing data
  //
  BufferIn = AllocateZeroPool (BufferInSize);
  if (BufferIn == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto ERROR;
  }

  //
  // Copy all TLS plain record header and payload to BufferIn
  //
  for (Index = 0; Index < *FragmentCount; Index++) {
    CopyMem (
      (BufferIn + BytesCopied),
      (*FragmentTable)[Index].FragmentBuffer,
      (*FragmentTable)[Index].FragmentLength
      );
    BytesCopied += (*FragmentTable)[Index].FragmentLength;
  }

  BufferOut = AllocateZeroPool (MAX_BUFFER_SIZE);
  if (BufferOut == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto ERROR;
  }

  //
  // Parsing buffer. Received packet may have multiple TLS record messages.
  //
  BufferInPtr = BufferIn;
  TempRecordHeader = (TLS_RECORD_HEADER *) BufferOut;
  while ((UINTN) BufferInPtr < (UINTN) BufferIn + BufferInSize) {
    RecordHeaderIn = (TLS_RECORD_HEADER *) BufferInPtr;

    if (RecordHeaderIn->ContentType != TLS_CONTENT_TYPE_APPLICATION_DATA) {
      Status = EFI_INVALID_PARAMETER;
      goto ERROR;
    }
    
    ThisCipherMessageSize = NTOHS (RecordHeaderIn->Length);

    Ret = TlsCtrlTrafficIn (TlsInstance->TlsConn, (UINT8 *) (RecordHeaderIn), RECORD_HEADER_LEN + ThisCipherMessageSize);
    if (Ret != RECORD_HEADER_LEN + ThisCipherMessageSize) {
      TlsInstance->TlsSessionState = EfiTlsSessionError;
      Status = EFI_ABORTED;
      goto ERROR;
    }

    Ret = 0;
    Ret = TlsRead (TlsInstance->TlsConn, (UINT8 *) (TempRecordHeader + 1), MAX_BUFFER_SIZE - BufferOutSize);

    if (Ret > 0) {
      ThisPlainMessageSize = (UINT16) Ret;
    } else {
      //
      // No data was successfully decrypted, continue to decrypt other messages.
      //
      DEBUG ((EFI_D_WARN, "TlsDecryptPacket: No data read from TLS object.\n"));
    
      ThisPlainMessageSize = 0;
    }

    CopyMem (TempRecordHeader, RecordHeaderIn, RECORD_HEADER_LEN);
    TempRecordHeader->Length = ThisPlainMessageSize;
    BufferOutSize += RECORD_HEADER_LEN + ThisPlainMessageSize;

    BufferInPtr += RECORD_HEADER_LEN + ThisCipherMessageSize;
    TempRecordHeader += RECORD_HEADER_LEN + ThisPlainMessageSize;
  }

  FreePool (BufferIn);
  BufferIn = NULL;

  //
  // The caller will be responsible to handle the original fragment table
  //
  *FragmentTable = AllocateZeroPool (sizeof (EFI_TLS_FRAGMENT_DATA));
  if (*FragmentTable == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto ERROR;
  }

  (*FragmentTable)[0].FragmentBuffer  = BufferOut;
  (*FragmentTable)[0].FragmentLength  = BufferOutSize;
  *FragmentCount                      = 1;

  return Status;

ERROR:
  
  if (BufferIn != NULL) {
    FreePool (BufferIn);
    BufferIn = NULL;
  }

  if (BufferOut != NULL) {
    FreePool (BufferOut);
    BufferOut = NULL;
  }
  
  return Status;  
}