Add Base32 extended hex encoder and decoder (GH #534)

I'm not sure if this is what the fellow in the issue wanted, but we are missing it. Also see https://stackoverflow.com/q/47325517/608639
weidai11 · Nov 28, 2017 · 8530b58 · 8530b58
1 parent 0db1ef2
commit 8530b58
Show file tree

Hide file tree

Showing 2 changed files with 118 additions and 8 deletions.
diff --git a/base32.cpp b/base32.cpp
@@ -1,13 +1,17 @@
 // base32.cpp - written and placed in the public domain by Frank Palazzolo, based on hex.cpp by Wei Dai
+//              extended hex alphabet added by JW in November, 2017.
 
 #include "pch.h"
 #include "base32.h"
 
 NAMESPACE_BEGIN(CryptoPP)
 ANONYMOUS_NAMESPACE_BEGIN
 
-const byte s_vecUpper[] = "ABCDEFGHIJKMNPQRSTUVWXYZ23456789";
-const byte s_vecLower[] = "abcdefghijkmnpqrstuvwxyz23456789";
+const byte s_stdUpper[] = "ABCDEFGHIJKMNPQRSTUVWXYZ23456789";
+const byte s_stdLower[] = "abcdefghijkmnpqrstuvwxyz23456789";
+const byte s_hexUpper[] = "0123456789ABCDEFGHIJKLMNOPQRSTUV";
+const byte s_hexLower[] = "0123456789abcdefghijklmnopqrstuv";
+
 const int s_array[256] = {
 	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
@@ -27,14 +31,33 @@ const int s_array[256] = {
 	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
 };
 
+const int s_hexArray[256] = {
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, -1, -1, -1, -1, -1, -1,
+	-1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
+	25, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
+	25, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
+};
+
 ANONYMOUS_NAMESPACE_END
 
 void Base32Encoder::IsolatedInitialize(const NameValuePairs &parameters)
 {
 	bool uppercase = parameters.GetValueWithDefault(Name::Uppercase(), true);
 	m_filter->Initialize(CombinedNameValuePairs(
 		parameters,
-		MakeParameters(Name::EncodingLookupArray(), uppercase ? &s_vecUpper[0] : &s_vecLower[0], false)(Name::Log2Base(), 5, true)));
+		MakeParameters(Name::EncodingLookupArray(), uppercase ? &s_stdUpper[0] : &s_stdLower[0], false)(Name::Log2Base(), 5, true)));
 }
 
 void Base32Decoder::IsolatedInitialize(const NameValuePairs &parameters)
@@ -50,4 +73,25 @@ const int *Base32Decoder::GetDefaultDecodingLookupArray()
 	return s_array;
 }
 
+void Base32HexEncoder::IsolatedInitialize(const NameValuePairs &parameters)
+{
+	bool uppercase = parameters.GetValueWithDefault(Name::Uppercase(), true);
+	m_filter->Initialize(CombinedNameValuePairs(
+		parameters,
+		MakeParameters(Name::EncodingLookupArray(), uppercase ? &s_hexUpper[0] : &s_hexLower[0], false)(Name::Log2Base(), 5, true)));
+}
+
+void Base32HexDecoder::IsolatedInitialize(const NameValuePairs &parameters)
+{
+	BaseN_Decoder::IsolatedInitialize(CombinedNameValuePairs(
+		parameters,
+		MakeParameters(Name::DecodingLookupArray(), GetDefaultDecodingLookupArray(), false)(Name::Log2Base(), 5, true)));
+}
+
+// Unrolled initialization, http://github.com/weidai11/cryptopp/issues/376
+const int *Base32HexDecoder::GetDefaultDecodingLookupArray()
+{
+	return s_hexArray;
+}
+
 NAMESPACE_END
diff --git a/base32.h b/base32.h
@@ -1,7 +1,8 @@
 // base32.h - written and placed in the public domain by Frank Palazzolo, based on hex.cpp by Wei Dai
+//              extended hex alphabet added by JW in November, 2017.
 
-//! \file
-//! \brief Classes for Base32Encoder and Base32Decoder
+//! \file base32.h
+//! \brief Classes for Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
 
 #ifndef CRYPTOPP_BASE32_H
 #define CRYPTOPP_BASE32_H
@@ -14,6 +15,7 @@ NAMESPACE_BEGIN(CryptoPP)
 //! \class Base32Encoder
 //! \brief Base32 encodes data
 //! \details Converts data to base32. The default code is based on <A HREF="http://www.ietf.org/proceedings/51/I-D/draft-ietf-idn-dude-02.txt">Differential Unicode Domain Encoding (DUDE) (draft-ietf-idn-dude-02.txt)</A>.
+//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
 class Base32Encoder : public SimpleProxyFilter
 {
 public:
@@ -25,7 +27,7 @@ class Base32Encoder : public SimpleProxyFilter
 	//! \param terminator the terminator appeand after processing
 	//! \details Base32Encoder() constructs a default encoder. The constructor lacks fields for padding and
 	//!   line breaks. You must use IsolatedInitialize() to change the default padding character or suppress it.
-	//! \sa IsolatedInitialize() for an example of modifying a Base32Encoder after construction.
+	//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
 	Base32Encoder(BufferedTransformation *attachment = NULLPTR, bool uppercase = true, int groupSize = 0, const std::string &separator = ":", const std::string &terminator = "")
 		: SimpleProxyFilter(new BaseN_Encoder(new Grouper), attachment)
 	{
@@ -51,13 +53,14 @@ class Base32Encoder : public SimpleProxyFilter
 	//!     encoder.IsolatedInitialize(params);</pre>
 	//! \details If you change the encoding alphabet, then you will need to change the decoding alphabet \a and
 	//!   the decoder's lookup table.
-	//! \sa Base32Decoder::IsolatedInitialize() for an example of changing a Base32Decoder's lookup table.
+	//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
 	void IsolatedInitialize(const NameValuePairs &parameters);
 };
 
 //! \class Base32Decoder
 //! \brief Base32 decodes data
 //! \details Decode base32 data. The default code is based on <A HREF="http://www.ietf.org/proceedings/51/I-D/draft-ietf-idn-dude-02.txt">Differential Unicode Domain Encoding (DUDE) (draft-ietf-idn-dude-02.txt)</A>.
+//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
 class Base32Decoder : public BaseN_Decoder
 {
 public:
@@ -82,7 +85,70 @@ class Base32Decoder : public BaseN_Decoder
 	//!     Base32Decoder decoder;
 	//!     AlgorithmParameters params = MakeParameters(Name::DecodingLookupArray(),(const int *)lookup);
 	//!     decoder.IsolatedInitialize(params);</pre>
-	//! \sa Base32Encoder::IsolatedInitialize() for an example of changing a Base32Encoder's alphabet.
+	//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
+	void IsolatedInitialize(const NameValuePairs &parameters);
+
+private:
+	//! \brief Provides the default decoding lookup table
+	//! \return default decoding lookup table
+	static const int * CRYPTOPP_API GetDefaultDecodingLookupArray();
+};
+
+//! \class Base32HexEncoder
+//! \brief Base32 encodes data using extended hex
+//! \details Converts data to base32 using extended hex alphabet. The alphabet is different than Base32Encoder.
+//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder, <A HREF="http://tools.ietf.org/html/rfc4648#page-10">RFC 4648, Base 32 Encoding with Extended Hex Alphabet</A>.
+//! \since Crypto++ 6.0
+class Base32HexEncoder : public SimpleProxyFilter
+{
+public:
+	//! \brief Construct a Base32HexEncoder
+	//! \param attachment a BufferedTrasformation to attach to this object
+	//! \param uppercase a flag indicating uppercase output
+	//! \param groupSize the size of the grouping
+	//! \param separator the separator to use between groups
+	//! \param terminator the terminator appeand after processing
+	//! \details Base32HexEncoder() constructs a default encoder. The constructor lacks fields for padding and
+	//!   line breaks. You must use IsolatedInitialize() to change the default padding character or suppress it.
+	//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
+	Base32HexEncoder(BufferedTransformation *attachment = NULLPTR, bool uppercase = true, int groupSize = 0, const std::string &separator = ":", const std::string &terminator = "")
+		: SimpleProxyFilter(new BaseN_Encoder(new Grouper), attachment)
+	{
+		IsolatedInitialize(MakeParameters(Name::Uppercase(), uppercase)(Name::GroupSize(), groupSize)(Name::Separator(), ConstByteArrayParameter(separator))(Name::Terminator(), ConstByteArrayParameter(terminator)));
+	}
+
+	//! \brief Initialize or reinitialize this object, without signal propagation
+	//! \param parameters a set of NameValuePairs used to initialize this object
+	//! \details IsolatedInitialize() is used to initialize or reinitialize an object using a variable
+	//!   number of arbitrarily typed arguments. IsolatedInitialize() does not call Initialize() on attached
+	//!   transformations. If initialization should be propagated, then use the Initialize() function.
+	//! \details The following code modifies the padding and line break parameters for an encoder:
+	//!   <pre>
+	//!     Base32HexEncoder encoder;
+	//!     AlgorithmParameters params = MakeParameters(Pad(), false)(InsertLineBreaks(), false);
+	//!     encoder.IsolatedInitialize(params);</pre>
+	void IsolatedInitialize(const NameValuePairs &parameters);
+};
+
+//! \class Base32HexDecoder
+//! \brief Base32 extended hex decodes data
+//! \brief Base32 decodes data using extended hex alphabet. The alphabet is different than Base32Decoder.
+//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder, <A HREF="http://tools.ietf.org/html/rfc4648#page-10">RFC 4648, Base 32 Encoding with Extended Hex Alphabet</A>.
+//! \since Crypto++ 6.0
+class Base32HexDecoder : public BaseN_Decoder
+{
+public:
+	//! \brief Construct a Base32HexDecoder
+	//! \param attachment a BufferedTrasformation to attach to this object
+	//! \sa Base32Encoder, Base32Decoder, Base32HexEncoder and Base32HexDecoder
+	Base32HexDecoder(BufferedTransformation *attachment = NULLPTR)
+		: BaseN_Decoder(GetDefaultDecodingLookupArray(), 5, attachment) {}
+
+	//! \brief Initialize or reinitialize this object, without signal propagation
+	//! \param parameters a set of NameValuePairs used to initialize this object
+	//! \details IsolatedInitialize() is used to initialize or reinitialize an object using a variable
+	//!   number of arbitrarily typed arguments. IsolatedInitialize() does not call Initialize() on attached
+	//!   transformations. If initialization should be propagated, then use the Initialize() function.
 	void IsolatedInitialize(const NameValuePairs &parameters);
 
 private: