src/auth/password-scheme-otp.c

/*
 * OTP password scheme.
 *
 * Copyright (c) 2006 Andrey Panin <pazke@donpac.ru>
 *
 * This software is released under the MIT license.
 */

#include "lib.h"
#include "hex-binary.h"
#include "password-scheme.h"
#include "randgen.h"
#include "otp.h"

int password_generate_otp(const char *pw, const char *state_data,
              unsigned int algo, const char **result_r)
{
    struct otp_state state;

    if (state_data != NULL) {
        if (otp_parse_dbentry(state_data, &state) != 0)
            return -1;
    } else {
        /* Generate new OTP credentials from plaintext */
        unsigned char random_data[OTP_MAX_SEED_LEN / 2];
        const char *random_hex;

        random_fill(random_data, sizeof(random_data));
        random_hex = binary_to_hex(random_data, sizeof(random_data));
        if (i_strocpy(state.seed, random_hex, sizeof(state.seed)) < 0)
            i_unreached();

        state.seq = 1024;
        state.algo = algo;
    }

    otp_hash(state.algo, state.seed, pw, state.seq, state.hash);
    *result_r = otp_print_dbentry(&state);
    return 0;
}