AESPHM_Decrypt(key, password, password)

[Skrip]

Does anybody have an AESPHM decryption in AutoIt? If so, please post it here.

I have some source for this decryption. But I haven't any clue how to convert it to autoit.

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int AESPHM_Decrypt(u8 *passphrase, u8 *output, u8 *input) {
    AES_KEY ctx;
    int  inputlen,
            ivoff,
            paddingLen,
            payloadLen;
    u8    key[SHA256_DIGEST_LENGTH],
            iv[IV_SIZE],
            checkDigest[HMAC_SHA_DIGESTSIZE],
            firstPadByte,
            *digest,
            *ivSeed,
            *payload;

    input = strdup(input);

    inputlen = hex2byte(input, input);
    if(inputlen < MINIMUM_CIPHERTEXT_LENGTH) {
        fprintf(stderr, "\nError: the encrypted hex password (%d) is shorter than %d bytes\n", inputlen, MINIMUM_CIPHERTEXT_LENGTH);
        free(input);
        return(-1);
    }

    digest = input + inputlen - HMAC_SHA_DIGESTSIZE;
    ivSeed = digest - IV_SEED_SIZE;

    SHA256(passphrase, strlen(passphrase), key);
    HMAC(EVP_sha1(), key, SHA256_DIGEST_LENGTH, input, digest - input, checkDigest, NULL);

    if(memcmp(checkDigest, digest, HMAC_SHA_DIGESTSIZE)) {
        fprintf(stderr, "\nError: the hmac checksum differs, the key is wrong\n");
        free(input);
        return(-1);
    }

    AESPHM_GenerateIvFromSeed(ivSeed, iv);

    AES_set_encrypt_key(key, SHA256_DIGEST_LENGTH << 3, &ctx);
    ivoff = 0;  // AES_cfb128_encrypt in OpenSSL, but due to a difference with Crypto++ I use myaesdec
    myaesdec(&ctx, 1, &ivoff, iv, input, &firstPadByte);

    paddingLen = (firstPadByte & 15) + 3;
    if((input + paddingLen) > ivSeed) {
        fprintf(stderr, "\nError: the initial padded bytes (%d) are longer than the seed (%d)\n", paddingLen, IV_SEED_SIZE);
        free(input);
        return(-1);
    }

    payload = input + paddingLen;
    payloadLen = ivSeed - payload;
    if(payloadLen) {
        myaesdec(&ctx, paddingLen - 1, &ivoff, iv, input + 1, output);
        myaesdec(&ctx, payloadLen, &ivoff, iv, payload, output);
    }

    free(input);
    return(payloadLen);
}