Handle base64 encoding and decoding

4 files changed, 70 insertions, 14 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8140805..b875512 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -72,11 +72,13 @@ set_target_properties(noscrypt PROPERTIES NC_ENABLE_UTILS ON)   #utilities libra
 #======== Build the project ========#
 set(INCLUDE_DIR ./include)
 set(CLIENT_INCLUDE_DIR ./include/client)
+set(CRYPTOGRAPHY_INCLUDE_DIR ./include/cryptography)
 set(DATA_INCLUDE_DIR ./include/data)
 set(SERVICE_INCLUDE_DIR ./include/service)
 set(SIGNER_INCLUDE_DIR ./include/signer)
 include_directories(${INCLUDE_DIR})
 include_directories(${CLIENT_INCLUDE_DIR})
+include_directories(${CRYPTOGRAPHY_INCLUDE_DIR})
 include_directories(${DATA_INCLUDE_DIR})
 include_directories(${SIGNER_INCLUDE_DIR})
 
@@ -84,6 +86,7 @@ set(HEADERS
     ${INCLUDE_DIR}/nostr.hpp
     ${CLIENT_INCLUDE_DIR}/web_socket_client.hpp
     ${CLIENT_INCLUDE_DIR}/websocketpp_client.hpp
+    ${CRYPTOGRAPHY_INCLUDE_DIR}/noscrypt_cipher.hpp
     ${DATA_INCLUDE_DIR}/data.hpp
     ${SERVICE_INCLUDE_DIR}/nostr_service_base.hpp
     ${SIGNER_INCLUDE_DIR}/signer.hpp
@@ -92,16 +95,17 @@ set(HEADERS
 
 set(SOURCE_DIR ./src)
 set(CLIENT_SOURCE_DIR ./src/client)
+set(CRYPTOGRAPHY_SOURCE_DIR ./src/cryptography)
 set(DATA_SOURCE_DIR ./src/data)
 set(SERVICE_SOURCE_DIR ./src/service)
 set(SIGNER_SOURCE_DIR ./src/signer)
 set(SOURCES
     ${CLIENT_SOURCE_DIR}/websocketpp_client.cpp
+    ${CRYPTOGRAPHY_SOURCE_DIR}/noscrypt_cipher.cpp
     ${DATA_SOURCE_DIR}/event.cpp
     ${DATA_SOURCE_DIR}/filters.cpp
     ${SERVICE_SOURCE_DIR}/nostr_service_base.cpp
     ${SIGNER_SOURCE_DIR}/noscrypt_signer.cpp
-    ${SIGNER_SOURCE_DIR}/noscrypt_cipher.cpp
 )
 
 add_library(aedile ${SOURCES})
diff --git a/src/signer/noscrypt_cipher.hpp b/include/cryptography/noscrypt_cipher.hpp
index ffe4bec..3337240 100644
--- a/src/signer/noscrypt_cipher.hpp
+++ b/include/cryptography/noscrypt_cipher.hpp
@@ -1,3 +1,4 @@
+#pragma once
 
 #include <memory>
 
@@ -6,7 +7,7 @@
 
 namespace nostr
 {
-namespace signer
+namespace cryptography
 {
 class NoscryptCipherContext
 {
@@ -144,17 +145,29 @@ public:
         const std::string& input
     );
 
-    static std::string naiveEncodeBase64(const std::string& str)
+    /**
+     * @brief Computes the length of a base64 encoded string.
+     * @param n The length of the string to be encoded.
+     * @return The length of the resulting base64 encoded string.
+     */
+    inline static size_t base64EncodedSize(const size_t n)
     {
-        //TODO Implement base64 encoding
-        return str;
-    }
+        return (((n + 2) / 3) << 2) + 1;
+    };
 
-    static std::string naiveDecodeBase64(const std::string& str)
+    /**
+     * @brief Computes the length of a string decoded from base64.
+     * @param n The length of the base64 encoded string.
+     * @return The length of the decoded string.
+     */
+    inline static size_t base64DecodedSize(const size_t n)
     {
-        //TODO Implement base64 decoding
-        return str;
-    }
+        return (n * 3) >> 2;
+    };
+
+    static std::string naiveEncodeBase64(const std::string& str);
+
+    static std::string naiveDecodeBase64(const std::string& str);
 };
-} // namespace signer
+} // namespace cryptography
 } // namespace nostr
diff --git a/src/signer/noscrypt_cipher.cpp b/src/cryptography/noscrypt_cipher.cpp
index d751261..ae9aaf0 100644
--- a/src/signer/noscrypt_cipher.cpp
+++ b/src/cryptography/noscrypt_cipher.cpp
@@ -1,12 +1,12 @@
 #include <plog/Init.h>
 #include <plog/Log.h>
-#include <noscryptutil.h>
 
+#include <openssl/evp.h>
 #include <openssl/rand.h>
 
-#include "noscrypt_cipher.hpp"
+#include "cryptography/noscrypt_cipher.hpp"
 
-using namespace nostr::signer;
+using namespace nostr::cryptography;
 using namespace std;
 
 static void _printNoscryptError(NCResult result, const std::string funcName, int lineNum)
@@ -143,3 +143,41 @@ result = this->_cipher.setInput(inputBuffer);
 
     return string(output.begin(), output.end());
 }
+
+string NoscryptCipher::naiveEncodeBase64(const std::string& str)
+{
+    // Compute base64 size and allocate a string buffer of that size.
+    const size_t encodedSize = NoscryptCipher::base64EncodedSize(str.size());
+    unsigned char* encodedData = new unsigned char[encodedSize];
+
+    // Encode the input string to base64.
+    EVP_EncodeBlock(encodedData, (const unsigned char*)str.data(), str.size());
+
+    // Construct the encoded string from the buffer.
+    string encodedStr((char*)encodedData);
+
+    // Zero out the buffer and delete the pointer.
+    memset(encodedData, 0, encodedSize);
+    delete [] encodedData;
+
+    return encodedStr;
+}
+
+string NoscryptCipher::naiveDecodeBase64(const string& str)
+{
+    // Compute the size of the decoded string and allocate a buffer of that size.
+    const size_t decodedSize = NoscryptCipher::base64DecodedSize(str.size());
+    unsigned char* decodedData = new unsigned char[decodedSize];
+
+    // Decode the input string from base64.
+    EVP_DecodeBlock(decodedData, (const unsigned char*)str.data(), str.size());
+
+    // Construct the decoded string from the buffer.
+    string decodedStr((char*)decodedData);
+
+    // Zero out the buffer and delete the pointer.
+    memset(decodedData, 0, decodedSize);
+    delete [] decodedData;
+
+    return decodedStr;
+};
diff --git a/src/signer/noscrypt_signer.cpp b/src/signer/noscrypt_signer.cpp
index 3cf4b6f..2b87703 100644
--- a/src/signer/noscrypt_signer.cpp
+++ b/src/signer/noscrypt_signer.cpp
@@ -17,6 +17,7 @@
 using namespace nostr::data;
 using namespace nostr::service;
 using namespace nostr::signer;
+using namespace nostr::cryptography;
 using namespace std;
 
 #pragma region Constructors and Destructors