Re: [PATCH v5] MdePkg/BaseLib: Add Base64Encode() and Base64Decode()

["Gao, Liming" <liming.gao@intel.com>]

Reviewed-by: Liming Gao <liming.gao@intel.com>

> -----Original Message-----
> From: Zhang, Shenglei
> Sent: Thursday, January 31, 2019 3:37 PM
> To: edk2-devel@lists.01.org
> Cc: Mike Turner <miketur@microsoft.com>; Kinney, Michael D <michael.d.kinney@intel.com>; Gao, Liming <liming.gao@intel.com>
> Subject: [PATCH v5] MdePkg/BaseLib: Add Base64Encode() and Base64Decode()
> 
> From: Mike Turner <miketur@microsoft.com>
> 
> Introduce public functions Base64Encode and Base64Decode.
> https://bugzilla.tianocore.org/show_bug.cgi?id=1370
> 
> v2:1.Remove some white space.
>    2.Add unit test with test vectors in RFC 4648.
>      https://github.com/shenglei10/edk2/tree/encode_test
>      https://github.com/shenglei10/edk2/tree/decode_test
> 
> v3:1.Align white space.
>    2.Update comments of Base64Encode and Base64Decode.
>    3.Change the use of macro RETURN_DEVICE_ERROR to
>      RETURN_INVALID_PARAMETER in string.c.
> 
> v4:Change parameters' names.
> 
> v5:1.Update usage of variables.
>    2.Remove debug message in Base64Decode().
> 
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Cc: Liming Gao <liming.gao@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
> ---
>  MdePkg/Include/Library/BaseLib.h |  56 ++++++
>  MdePkg/Library/BaseLib/String.c  | 331 +++++++++++++++++++++++++++++++
>  2 files changed, 387 insertions(+)
> 
> diff --git a/MdePkg/Include/Library/BaseLib.h b/MdePkg/Include/Library/BaseLib.h
> index 1eb842384e..03173def58 100644
> --- a/MdePkg/Include/Library/BaseLib.h
> +++ b/MdePkg/Include/Library/BaseLib.h
> @@ -2720,6 +2720,62 @@ AsciiStrnToUnicodeStrS (
>    OUT     UINTN                     *DestinationLength
>    );
> 
> +/**
> +  Convert binary data to a Base64 encoded ascii string based on RFC4648.
> +
> +  Produce a Null-terminated Ascii string in the output buffer specified by Destination and DestinationSize.
> +  The Ascii string is produced by converting the data string specified by Source and SourceLength.
> +
> +  @param Source           Input UINT8 data
> +  @param SourceLength     Number of UINT8 bytes of data
> +  @param Destination      Pointer to output string buffer
> +  @param DestinationSize  Size of ascii buffer. Set to 0 to get the size needed.
> +                          Caller is responsible for passing in buffer of DestinationSize
> +
> +  @retval RETURN_SUCCESS             When ascii buffer is filled in.
> +  @retval RETURN_INVALID_PARAMETER   If Source is NULL or DestinationSize is NULL.
> +  @retval RETURN_INVALID_PARAMETER   If SourceLength or DestinationSize is bigger than (MAX_ADDRESS - (UINTN)Destination).
> +  @retval RETURN_BUFFER_TOO_SMALL    If SourceLength is 0 and DestinationSize is <1.
> +  @retval RETURN_BUFFER_TOO_SMALL    If Destination is NULL or DestinationSize is smaller than required buffersize.
> +
> +**/
> +RETURN_STATUS
> +EFIAPI
> +Base64Encode (
> +  IN  CONST UINT8  *Source,
> +  IN        UINTN   SourceLength,
> +  OUT       CHAR8  *Destination  OPTIONAL,
> +  IN OUT    UINTN  *DestinationSize
> +  );
> +
> +/**
> +  Convert Base64 ascii string to binary data based on RFC4648.
> +
> +  Produce Null-terminated binary data in the output buffer specified by Destination and DestinationSize.
> +  The binary data is produced by converting the Base64 ascii string specified by Source and SourceLength.
> +
> +  @param Source          Input ASCII characters
> +  @param SourceLength    Number of ASCII characters
> +  @param Destination     Pointer to output buffer
> +  @param DestinationSize Caller is responsible for passing in buffer of at least DestinationSize.
> +                         Set 0 to get the size needed. Set to bytes stored on return.
> +
> +  @retval RETURN_SUCCESS             When binary buffer is filled in.
> +  @retval RETURN_INVALID_PARAMETER   If Source is NULL or DestinationSize is NULL.
> +  @retval RETURN_INVALID_PARAMETER   If SourceLength or DestinationSize is bigger than (MAX_ADDRESS -(UINTN)Destination ).
> +  @retval RETURN_INVALID_PARAMETER   If there is any invalid character in input stream.
> +  @retval RETURN_BUFFER_TOO_SMALL    If buffer length is smaller than required buffer size.
> +
> + **/
> +RETURN_STATUS
> +EFIAPI
> +Base64Decode (
> +  IN  CONST CHAR8  *Source,
> +  IN        UINTN   SourceLength,
> +  OUT       UINT8  *Destination  OPTIONAL,
> +  IN OUT    UINTN  *DestinationSize
> +  );
> +
>  /**
>    Converts an 8-bit value to an 8-bit BCD value.
> 
> diff --git a/MdePkg/Library/BaseLib/String.c b/MdePkg/Library/BaseLib/String.c
> index e6df12797d..87d0a9d1dc 100644
> --- a/MdePkg/Library/BaseLib/String.c
> +++ b/MdePkg/Library/BaseLib/String.c
> @@ -1763,6 +1763,337 @@ AsciiStrToUnicodeStr (
> 
>  #endif
> 
> +//
> +// The basis for Base64 encoding is RFC 4686 https://tools.ietf.org/html/rfc4648
> +//
> +// RFC 4686 has a number of MAY and SHOULD cases.  This implementation chooses
> +// the more restrictive versions for security concerns (see RFC 4686 section 3.3).
> +//
> +// A invalid character, if encountered during the decode operation, causes the data
> +// to be rejected. In addition, the '=' padding character is only allowed at the end
> +// of the Base64 encoded string.
> +//
> +#define BAD_V  99
> +
> +STATIC CHAR8 Encoding_table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
> +                                "abcdefghijklmnopqrstuvwxyz"
> +                                "0123456789+/";
> +
> +STATIC UINT8 Decoding_table[] = {
> +  //
> +  // Valid characters ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/
> +  // Also, set '=' as a zero for decoding
> +  // 0  ,            1,           2,           3,            4,           5,            6,           7,           8,
> 9,           a,            b,            c,           d,            e,            f
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //   0
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  10
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,     62,  BAD_V,  BAD_V,
> BAD_V,     63,   //  20
> +     52,     53,     54,     55,     56,     57,     58,     59,     60,     61,  BAD_V,  BAD_V,  BAD_V,      0,  BAD_V,
> BAD_V,   //  30
> +  BAD_V,      0,      1,      2,      3,      4,      5,      6,      7,      8,      9,     10,     11,     12,     13,
> 14,   //  40
> +     15,     16,     17,     18,     19,     20,     21,     22,     23,     24,     25,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,   //  50
> +  BAD_V,     26,     27,     28,     29,     30,     31,     32,     33,     34,     35,     36,     37,     38,     39,
> 40,   //  60
> +     41,     42,     43,     44,     45,     46,     47,     48,     49,     50,     51,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,   //  70
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  80
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  90
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  a0
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  b0
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  c0
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  d0
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V,   //  d0
> +  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,  BAD_V,
> BAD_V,  BAD_V    //  f0
> +};
> +
> +/**
> +  Convert binary data to a Base64 encoded ascii string based on RFC4648.
> +
> +  Produce a Null-terminated Ascii string in the output buffer specified by Destination and DestinationSize.
> +  The Ascii string is produced by converting the data string specified by Source and SourceLength.
> +
> +  @param Source            Input UINT8 data
> +  @param SourceLength      Number of UINT8 bytes of data
> +  @param Destination       Pointer to output string buffer
> +  @param DestinationSize   Size of ascii buffer. Set to 0 to get the size needed.
> +                           Caller is responsible for passing in buffer of DestinationSize
> +
> +  @retval RETURN_SUCCESS             When ascii buffer is filled in.
> +  @retval RETURN_INVALID_PARAMETER   If Source is NULL or DestinationSize is NULL.
> +  @retval RETURN_INVALID_PARAMETER   If SourceLength or DestinationSize is bigger than (MAX_ADDRESS - (UINTN)Destination).
> +  @retval RETURN_BUFFER_TOO_SMALL    If SourceLength is 0 and DestinationSize is <1.
> +  @retval RETURN_BUFFER_TOO_SMALL    If Destination is NULL or DestinationSize is smaller than required buffersize.
> +
> +**/
> +RETURN_STATUS
> +EFIAPI
> +Base64Encode (
> +  IN  CONST UINT8  *Source,
> +  IN        UINTN   SourceLength,
> +  OUT       CHAR8  *Destination   OPTIONAL,
> +  IN OUT    UINTN  *DestinationSize
> +  )
> +{
> +
> +  UINTN          RequiredSize;
> +  UINTN          Left;
> +
> +  //
> +  // Check pointers, and SourceLength is valid
> +  //
> +  if ((Source == NULL) || (DestinationSize == NULL)) {
> +    return RETURN_INVALID_PARAMETER;
> +  }
> +
> +  //
> +  // Allow for RFC 4648 test vector 1
> +  //
> +  if (SourceLength == 0) {
> +    if (*DestinationSize < 1) {
> +      *DestinationSize = 1;
> +      return RETURN_BUFFER_TOO_SMALL;
> +    }
> +    *DestinationSize = 1;
> +    *Destination = '\0';
> +    return RETURN_SUCCESS;
> +  }
> +
> +  //
> +  // Check if SourceLength or  DestinationSize is valid
> +  //
> +  if ((SourceLength >= (MAX_ADDRESS - (UINTN)Source)) || (*DestinationSize >= (MAX_ADDRESS - (UINTN)Destination))){
> +    return RETURN_INVALID_PARAMETER;
> +  }
> +
> +  //
> +  // 4 ascii per 3 bytes + NULL
> +  //
> +  RequiredSize = ((SourceLength + 2) / 3) * 4 + 1;
> +  if ((Destination == NULL) || *DestinationSize < RequiredSize) {
> +    *DestinationSize = RequiredSize;
> +    return RETURN_BUFFER_TOO_SMALL;
> +  }
> +
> +  Left = SourceLength;
> +
> +  //
> +  // Encode 24 bits (three bytes) into 4 ascii characters
> +  //
> +  while (Left >= 3) {
> +
> +    *Destination++ = Encoding_table[( Source[0] & 0xfc) >> 2 ];
> +    *Destination++ = Encoding_table[((Source[0] & 0x03) << 4) + ((Source[1] & 0xf0) >> 4)];
> +    *Destination++ = Encoding_table[((Source[1] & 0x0f) << 2) + ((Source[2] & 0xc0) >> 6)];
> +    *Destination++ = Encoding_table[( Source[2] & 0x3f)];
> +    Left -= 3;
> +    Source += 3;
> +  }
> +
> +  //
> +  // Handle the remainder, and add padding '=' characters as necessary.
> +  //
> +  switch (Left) {
> +    case 0:
> +
> +      //
> +      // No bytes Left, done.
> +      //
> +      break;
> +    case 1:
> +
> +      //
> +      // One more data byte, two pad characters
> +      //
> +      *Destination++ = Encoding_table[( Source[0] & 0xfc) >> 2];
> +      *Destination++ = Encoding_table[((Source[0] & 0x03) << 4)];
> +      *Destination++ = '=';
> +      *Destination++ = '=';
> +      break;
> +    case 2:
> +
> +      //
> +      // Two more data bytes, and one pad character
> +      //
> +      *Destination++ = Encoding_table[( Source[0] & 0xfc) >> 2];
> +      *Destination++ = Encoding_table[((Source[0] & 0x03) << 4) + ((Source[1] & 0xf0) >> 4)];
> +      *Destination++ = Encoding_table[((Source[1] & 0x0f) << 2)];
> +      *Destination++ = '=';
> +      break;
> +    }
> +  //
> +  // Add terminating NULL
> +  //
> +  *Destination = '\0';
> +  return RETURN_SUCCESS;
> +}
> +
> +/**
> +  Convert Base64 ascii string to binary data based on RFC4648.
> +
> +  Produce Null-terminated binary data in the output buffer specified by Destination and DestinationSize.
> +  The binary data is produced by converting the Base64 ascii string specified by Source and SourceLength.
> +
> +  @param Source            Input ASCII characters
> +  @param SourceLength      Number of ASCII characters
> +  @param Destination       Pointer to output buffer
> +  @param DestinationSize   Caller is responsible for passing in buffer of at least DestinationSize.
> +                           Set 0 to get the size needed. Set to bytes stored on return.
> +
> +  @retval RETURN_SUCCESS             When binary buffer is filled in.
> +  @retval RETURN_INVALID_PARAMETER   If Source is NULL or DestinationSize is NULL.
> +  @retval RETURN_INVALID_PARAMETER   If SourceLength or DestinationSize is bigger than (MAX_ADDRESS -(UINTN)Destination ).
> +  @retval RETURN_INVALID_PARAMETER   If there is any invalid character in input stream.
> +  @retval RETURN_BUFFER_TOO_SMALL    If buffer length is smaller than required buffer size.
> + **/
> +RETURN_STATUS
> +EFIAPI
> +Base64Decode (
> +  IN  CONST CHAR8  *Source,
> +  IN        UINTN   SourceLength,
> +  OUT       UINT8  *Destination   OPTIONAL,
> +  IN OUT    UINTN  *DestinationSize
> +  )
> +{
> +
> +  UINT32   Value;
> +  CHAR8    Chr;
> +  INTN     BufferSize;
> +  UINTN    SourceIndex;
> +  UINTN    DestinationIndex;
> +  UINTN    Index;
> +  UINTN    ActualSourceLength;
> +
> +  //
> +  // Check pointers are not NULL
> +  //
> +  if ((Source == NULL) || (DestinationSize == NULL)) {
> +    return RETURN_INVALID_PARAMETER;
> +  }
> +
> +  //
> +  // Check if SourceLength or  DestinationSize is valid
> +  //
> +  if ((SourceLength >= (MAX_ADDRESS - (UINTN)Source)) || (*DestinationSize >= (MAX_ADDRESS - (UINTN)Destination))){
> +    return RETURN_INVALID_PARAMETER;
> +  }
> +
> +  ActualSourceLength = 0;
> +  BufferSize = 0;
> +
> +  //
> +  // Determine the actual number of valid characters in the string.
> +  // All invalid characters except selected white space characters,
> +  // will cause the Base64 string to be rejected. White space to allow
> +  // properly formatted XML will be ignored.
> +  //
> +  // See section 3.3 of RFC 4648.
> +  //
> +  for (SourceIndex = 0; SourceIndex < SourceLength; SourceIndex++) {
> +
> +    //
> +    // '=' is part of the quantum
> +    //
> +    if (Source[SourceIndex] == '=') {
> +      ActualSourceLength++;
> +      BufferSize--;
> +
> +      //
> +      // Only two '=' characters can be valid.
> +      //
> +      if (BufferSize < -2) {
> +        return RETURN_INVALID_PARAMETER;
> +      }
> +    }
> +    else {
> +      Chr = Source[SourceIndex];
> +      if (BAD_V != Decoding_table[(UINT8) Chr]) {
> +
> +        //
> +        // The '=' characters are only valid at the end, so any
> +        // valid character after an '=', will be flagged as an error.
> +        //
> +        if (BufferSize < 0) {
> +          return RETURN_INVALID_PARAMETER;
> +        }
> +          ActualSourceLength++;
> +      }
> +        else {
> +
> +        //
> +        // The reset of the decoder will ignore all invalid characters allowed here.
> +        // Ignoring selected white space is useful.  In this case, the decoder will
> +        // ignore ' ', '\t', '\n', and '\r'.
> +        //
> +        if ((Chr != ' ') &&(Chr != '\t') &&(Chr != '\n') &&(Chr != '\r')) {
> +          return RETURN_INVALID_PARAMETER;
> +        }
> +      }
> +    }
> +  }
> +
> +  //
> +  // The Base64 character string must be a multiple of 4 character quantums.
> +  //
> +  if (ActualSourceLength % 4 != 0) {
> +    return RETURN_INVALID_PARAMETER;
> +  }
> +
> +  BufferSize += ActualSourceLength / 4 * 3;
> +    if (BufferSize < 0) {
> +      return RETURN_INVALID_PARAMETER;
> +  }
> +
> +  //
> +  // BufferSize is >= 0
> +  //
> +  if ((Destination == NULL) || (*DestinationSize < (UINTN) BufferSize)) {
> +    *DestinationSize = BufferSize;
> +    return RETURN_BUFFER_TOO_SMALL;
> +  }
> +
> +  //
> +  // If no decodable characters, return a size of zero. RFC 4686 test vector 1.
> +  //
> +  if (ActualSourceLength == 0) {
> +    *DestinationSize = 0;
> +    return RETURN_SUCCESS;
> +  }
> +
> +  //
> +  // Input data is verified to be a multiple of 4 valid charcters.  Process four
> +  // characters at a time. Uncounted (ie. invalid)  characters will be ignored.
> +  //
> +  for (SourceIndex = 0, DestinationIndex = 0; (SourceIndex < SourceLength) && (DestinationIndex < *DestinationSize); ) {
> +    Value = 0;
> +
> +    //
> +    // Get 24 bits of data from 4 input characters, each character representing 6 bits
> +    //
> +    for (Index = 0; Index < 4; Index++) {
> +      do {
> +      Chr = Decoding_table[(UINT8) Source[SourceIndex++]];
> +      } while (Chr == BAD_V);
> +      Value <<= 6;
> +      Value |= Chr;
> +    }
> +
> +    //
> +    // Store 3 bytes of binary data (24 bits)
> +    //
> +    *Destination++ = (UINT8) (Value >> 16);
> +    DestinationIndex++;
> +
> +    //
> +    // Due to the '=' special cases for the two bytes at the end,
> +    // we have to check the length and not store the padding data
> +    //
> +    if (DestinationIndex++ < *DestinationSize) {
> +      *Destination++ = (UINT8) (Value >>  8);
> +    }
> +    if (DestinationIndex++ < *DestinationSize) {
> +      *Destination++ = (UINT8) Value;
> +    }
> +  }
> +
> +  return RETURN_SUCCESS;
> +}
> +
>  /**
>    Converts an 8-bit value to an 8-bit BCD value.
> 
> --
> 2.18.0.windows.1