/*

 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdio.h>

#include "internal/cryptlib.h"

#include <openssl/x509.h>

#include <openssl/objects.h>

#include <openssl/evp.h>

#include <openssl/ui.h>

/* should be init to zeros. */

static char prompt_string[80];

void EVP_set_pw_prompt(const char *prompt)

{

    if (prompt == NULL)

        prompt_string[0] = '\0';

    else {

        strncpy(prompt_string, prompt, 79);

        prompt_string[79] = '\0';

    }

}

char *EVP_get_pw_prompt(void)

{

    if (prompt_string[0] == '\0')

        return NULL;

    else

        return prompt_string;

}

/*

 * For historical reasons, the standard function for reading passwords is in

 * the DES library -- if someone ever wants to disable DES, this function

 * will fail

 */

int EVP_read_pw_string(char *buf, int len, const char *prompt, int verify)

{

    return EVP_read_pw_string_min(buf, 0, len, prompt, verify);

}

int EVP_read_pw_string_min(char *buf, int min, int len, const char *prompt,

                           int verify)

{

    int ret = -1;

    char buff[BUFSIZ];

    UI *ui;

    if ((prompt == NULL) && (prompt_string[0] != '\0'))

        prompt = prompt_string;

    ui = UI_new();

    if (ui == NULL)

        return ret;

    if (UI_add_input_string(ui, prompt, 0, buf, min,

                            (len >= BUFSIZ) ? BUFSIZ - 1 : len) < 0

        || (verify

            && UI_add_verify_string(ui, prompt, 0, buff, min,

                                    (len >= BUFSIZ) ? BUFSIZ - 1 : len,

                                    buf) < 0))

        goto end;

    ret = UI_process(ui);

    OPENSSL_cleanse(buff, BUFSIZ);

 end:

    UI_free(ui);

    return ret;

}

int EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,

                   const unsigned char *salt, const unsigned char *data,

                   int datal, int count, unsigned char *key,

                   unsigned char *iv)

{

    EVP_MD_CTX *c;

    unsigned char md_buf[EVP_MAX_MD_SIZE];

    int niv, nkey, addmd = 0;

    unsigned int mds = 0, i;

    int rv = 0;

    nkey = EVP_CIPHER_key_length(type);

    niv = EVP_CIPHER_iv_length(type);

    OPENSSL_assert(nkey <= EVP_MAX_KEY_LENGTH);

    OPENSSL_assert(niv <= EVP_MAX_IV_LENGTH);

    if (data == NULL)

        return nkey;

    c = EVP_MD_CTX_new();

    if (c == NULL)

        goto err;

    for (;;) {

        if (!EVP_DigestInit_ex(c, md, NULL))

            goto err;

        if (addmd++)

            if (!EVP_DigestUpdate(c, &(md_buf[0]), mds))

                goto err;

        if (!EVP_DigestUpdate(c, data, datal))

            goto err;

        if (salt != NULL)

            if (!EVP_DigestUpdate(c, salt, PKCS5_SALT_LEN))

                goto err;

        if (!EVP_DigestFinal_ex(c, &(md_buf[0]), &mds))

            goto err;

        for (i = 1; i < (unsigned int)count; i++) {

            if (!EVP_DigestInit_ex(c, md, NULL))

                goto err;

            if (!EVP_DigestUpdate(c, &(md_buf[0]), mds))

                goto err;

            if (!EVP_DigestFinal_ex(c, &(md_buf[0]), &mds))

                goto err;

        }

        i = 0;

        if (nkey) {

            for (;;) {

                if (nkey == 0)

                    break;

                if (i == mds)

                    break;

                if (key != NULL)

                    *(key++) = md_buf[i];

                nkey--;

                i++;

            }

        }

        if (niv && (i != mds)) {

            for (;;) {

                if (niv == 0)

                    break;

                if (i == mds)

                    break;

                if (iv != NULL)

                    *(iv++) = md_buf[i];

                niv--;

                i++;

            }

        }

        if ((nkey == 0) && (niv == 0))

            break;

    }

    rv = EVP_CIPHER_key_length(type);

 err:

    EVP_MD_CTX_free(c);

    OPENSSL_cleanse(md_buf, sizeof(md_buf));

    return rv;

}