1 files changed, 183 insertions, 0 deletions
diff --git a/src/cryptography/noscrypt_cipher.cpp b/src/cryptography/noscrypt_cipher.cpp
new file mode 100644
index 0000000..ae9aaf0
--- /dev/null
+++ b/src/cryptography/noscrypt_cipher.cpp
@@ -0,0 +1,183 @@
+#include <plog/Init.h>
+#include <plog/Log.h>
+
+#include <openssl/evp.h>
+#include <openssl/rand.h>
+
+#include "cryptography/noscrypt_cipher.hpp"
+
+using namespace nostr::cryptography;
+using namespace std;
+
+static void _printNoscryptError(NCResult result, const std::string funcName, int lineNum)
+{
+    uint8_t argPosition;
+
+    switch (NCParseErrorCode(result, &argPosition))
+    {
+    case E_NULL_PTR:
+        PLOG_ERROR << "noscrypt - error: A null pointer was passed in " << funcName << "(" << argPosition << ") at line " << lineNum;
+        break;
+
+    case E_INVALID_ARG:
+        PLOG_ERROR << "noscrypt - error: An invalid argument was passed in " << funcName << "(" << argPosition << ") at line " << lineNum;
+        break;
+
+    case E_INVALID_CONTEXT:
+        PLOG_ERROR << "noscrypt - error: An invalid context was passed in " << funcName << "(" << argPosition << ") on line " << lineNum;
+        break;
+
+    case E_ARGUMENT_OUT_OF_RANGE:
+        PLOG_ERROR << "noscrypt - error: An argument was out of range in " << funcName << "(" << argPosition << ") at line " << lineNum;
+        break;
+
+    case E_OPERATION_FAILED:
+        PLOG_ERROR << "noscrypt - error: An operation failed in " << funcName << "(" << argPosition << ") at line " << lineNum;
+        break;
+
+    default:
+        PLOG_ERROR << "noscrypt - error: An unknown error " << result << " occurred in " << funcName << "(" << argPosition << ") at line " << lineNum;
+        break;
+    }
+
+}
+
+#define LOG_NC_ERROR(result) _printNoscryptError(result, __func__, __LINE__)
+
+NoscryptCipher::NoscryptCipher(uint32_t version, uint32_t mode) :
+ _cipher(version, mode)
+{
+    /*
+    * We can know what iv size we need for the cipher now and allocate
+    * a buffer just to save some allocations and code during the
+    * encryption phase. This buffer is only needed during an encryption
+    * operation.
+    */
+
+    if ((mode & NC_UTIL_CIPHER_MODE) == NC_UTIL_CIPHER_MODE_ENCRYPT)
+    {
+        //Resize the vector to the size of the current cipher
+        this->_ivBuffer.resize(this->_cipher.ivSize());
+
+        //Safe to assign the iv to the context now and it will maintain a pointer to the buffer
+        this->_cipher.setIV(this->_ivBuffer);
+    }
+}
+
+std::string NoscryptCipher::update(
+    const std::shared_ptr<const NCContext> libContext,
+    const std::shared_ptr<const NCSecretKey> localKey,
+    const std::shared_ptr<const NCPublicKey> remoteKey,
+    const std::string& input
+)
+{
+    NCResult result;
+
+    //Argument exception if the input is empty
+    if (input.empty())
+    {
+        return string();
+    }
+
+    //Safely convert the string to a vector of bytes (allocates and copies, so maybe speed up later)
+    const vector<uint8_t> inputBuffer(input.begin(), input.end());
+
+result = this->_cipher.setInput(inputBuffer);
+    if (result != NC_SUCCESS)
+    {
+        LOG_NC_ERROR(result);
+        return string();
+    }
+
+    /*
+    * If were in encryption mode a random nonce (iv) must be generated. The size was determined
+    * when the cipher was created and already assigned to the context, so we just need to assign
+    * the random data.
+    *
+    * Keep in mind, this will automatically work for nip44 and nip04, either the
+    * AES iv or the ChaCha nonce.
+    */
+    if ((this->_cipher.flags() & NC_UTIL_CIPHER_MODE) == NC_UTIL_CIPHER_MODE_ENCRYPT)
+    {
+        int code = RAND_bytes(
+            this->_ivBuffer.data(),
+            this->_ivBuffer.size()  //Size set in constructor
+        );
+
+        if (code <= 0)
+        {
+            PLOG_ERROR << "Failed to generate a nonce or IV for encryption.";
+            return string();
+        }
+    }
+
+    //Performs the operation (either encryption or decryption) 
+    result = this->_cipher.update(libContext, localKey, remoteKey);
+    if (result != NC_SUCCESS)
+    {
+        LOG_NC_ERROR(result);
+        return string();
+    }
+
+    /*
+    * Time to read the ciper output by getting the size of the output, then creating
+    * a string to store it to
+    */
+
+    NCResult outputSize = this->_cipher.outputSize();
+    if (outputSize <= 0)
+    {
+        LOG_NC_ERROR(outputSize);
+        return string();
+    }
+
+    //Alloc vector for reading input data (maybe only alloc once)
+    vector<uint8_t> output(outputSize);
+
+    result = this->_cipher.readOutput(output);
+    if (result != outputSize)
+    {
+        LOG_NC_ERROR(result);
+        return string();
+    }
+
+    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;
+};