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POInvalid Algorithm Specified CryptoAPI
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copied!<p>I am trying to decrypt something using 128BIT AES Decryption. When i attempt to calling CryptDecrypt i get an Error stating "Invalid Algorithm Specified". I get the same problem when using the library posted here: <a href="http://www.codeproject.com/KB/security/WinAES.aspx" rel="nofollow noreferrer">http://www.codeproject.com/KB/security/WinAES.aspx</a></p> <p>What can cause this error?</p> <p>I am using CryptoAPI along on vista64bit with visual studio 2008. I checked in the registry and the AES library is there...</p> <p>EDIT</p> <pre><code>BYTE*& encryptedData /* get data length */ HCRYPTPROV cryptoHandle = NULL; HCRYPTKEY aesKeyHandle = NULL; hr = InitWinCrypt(cryptoHandle); if(FAILED(hr)) { return hr; } AesKeyOffering aesKey = { {PLAINTEXTKEYBLOB, CUR_BLOB_VERSION, 0, CALG_AES_128}, 16, { 0xFF, 0x00, 0xFF, 0x1C, 0x1D, 0x1E, 0x03, 0x04, 0x05, 0x0F, 0x20, 0x21, 0xAD, 0xAF, 0xA4, 0x04 }}; if(CryptImportKey(cryptoHandle, (CONST BYTE*)&aesKey, sizeof(AesKeyOffering), NULL, 0, &aesKeyHandle) == FALSE) { // DO error return HRESULT_FROM_WIN32(GetLastError()); } if(CryptSetKeyParam(aesKeyHandle, KP_IV, { 0xFF, 0x00, 0xFF, 0x1C, 0x1D, 0x1E, 0x03, 0x04, 0x05, 0x0F, 0x20, 0x21, 0xAD, 0xAF, 0xA4, 0x04 } , 0) == FALSE) { return HRESULT_FROM_WIN32(GetLastError()); } BYTE blah2 = CRYPT_MODE_CBC; // set block mode if(CryptSetKeyParam(aesKeyHandle, KP_MODE, &blah2, 0) == FALSE) { // return HRESULT_FROM_WIN32(GetLastError()); } DWORD lol = dataLength / 16 + 1; DWORD lol2 = lol * 16; if(CryptDecrypt(aesKeyHandle, 0, TRUE, 0, encryptedData, &lol2) == FALSE) { return HRESULT_FROM_WIN32(GetLastError()); } </code></pre> <p>InitWinCrypt function</p> <pre><code> if(!CryptAcquireContextW(&cryptoHandle, NULL, L"Microsoft Enhanced RSA and AES Cryptographic Provider", PROV_RSA_AES, CRYPT_VERIFYCONTEXT)) { if(!CryptAcquireContextW(&cryptoHandle, NULL, L"Microsoft Enhanced RSA and AES Cryptographic Provider", PROV_RSA_AES, 0)) { return HRESULT_FROM_WIN32(GetLastError()); } else { return S_OK; } } return S_OK; </code></pre> <p>AesOffering struct:</p> <pre><code>struct AesKeyOffering { BLOBHEADER m_Header; DWORD m_KeyLength; BYTE Key[16]; }; </code></pre> <p>EDIT2</p> <p>After rebooting my computer, and remvoing the CBC chunk. I am now getting Bad Data Errors. The data decrypts fine in C#. But i need to do this using wincrypt.</p>

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