/*

 * Copyright 1999-2016 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/crypto.h>

# include <openssl/hmac.h>

# include <openssl/rand.h>

# include <openssl/pkcs12.h>

# include "p12_lcl.h"

int PKCS12_mac_present(const PKCS12 *p12)

{

    return p12->mac ? 1 : 0;

}

void PKCS12_get0_mac(const ASN1_OCTET_STRING **pmac,

                     const X509_ALGOR **pmacalg,

                     const ASN1_OCTET_STRING **psalt,

                     const ASN1_INTEGER **piter,

                     const PKCS12 *p12)

{

    if (p12->mac) {

        X509_SIG_get0(p12->mac->dinfo, pmacalg, pmac);

        if (psalt)

            *psalt = p12->mac->salt;

        if (piter)

            *piter = p12->mac->iter;

    } else {

        if (pmac)

            *pmac = NULL;

        if (pmacalg)

            *pmacalg = NULL;

        if (psalt)

            *psalt = NULL;

        if (piter)

            *piter = NULL;

    }

}

# define TK26_MAC_KEY_LEN 32

static int pkcs12_gen_gost_mac_key(const char *pass, int passlen,

                                   const unsigned char *salt, int saltlen,

                                   int iter, int keylen, unsigned char *key,

                                   const EVP_MD *digest)

{

    unsigned char out[96];

    if (keylen != TK26_MAC_KEY_LEN) {

        return 0;

    }

    if (!PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter,

                           digest, sizeof(out), out)) {

        return 0;

    }

    memcpy(key, out + sizeof(out) - TK26_MAC_KEY_LEN, TK26_MAC_KEY_LEN);

    OPENSSL_cleanse(out, sizeof(out));

    return 1;

}

/* Generate a MAC */

static int pkcs12_gen_mac(PKCS12 *p12, const char *pass, int passlen,

                          unsigned char *mac, unsigned int *maclen,

                          int (*pkcs12_key_gen)(const char *pass, int passlen,

                                                unsigned char *salt, int slen,

                                                int id, int iter, int n,

                                                unsigned char *out,

                                                const EVP_MD *md_type))

{

    const EVP_MD *md_type;

    HMAC_CTX *hmac = NULL;

    unsigned char key[EVP_MAX_MD_SIZE], *salt;

    int saltlen, iter;

    int md_size = 0;

    int md_type_nid;

    const X509_ALGOR *macalg;

    const ASN1_OBJECT *macoid;

    if (pkcs12_key_gen == NULL)

        pkcs12_key_gen = PKCS12_key_gen_utf8;

    if (!PKCS7_type_is_data(p12->authsafes)) {

        PKCS12err(PKCS12_F_PKCS12_GEN_MAC, PKCS12_R_CONTENT_TYPE_NOT_DATA);

        return 0;

    }

    salt = p12->mac->salt->data;

    saltlen = p12->mac->salt->length;

    if (!p12->mac->iter)

        iter = 1;

    else

        iter = ASN1_INTEGER_get(p12->mac->iter);

    X509_SIG_get0(p12->mac->dinfo, &macalg, NULL);

    X509_ALGOR_get0(&macoid, NULL, NULL, macalg);

    if ((md_type = EVP_get_digestbyobj(macoid)) == NULL) {

        PKCS12err(PKCS12_F_PKCS12_GEN_MAC, PKCS12_R_UNKNOWN_DIGEST_ALGORITHM);

        return 0;

    }

    md_size = EVP_MD_size(md_type);

    md_type_nid = EVP_MD_type(md_type);

    if (md_size < 0)

        return 0;

    if ((md_type_nid == NID_id_GostR3411_94

         || md_type_nid == NID_id_GostR3411_2012_256

         || md_type_nid == NID_id_GostR3411_2012_512)

        && !getenv("LEGACY_GOST_PKCS12")) {

        md_size = TK26_MAC_KEY_LEN;

        if (!pkcs12_gen_gost_mac_key(pass, passlen, salt, saltlen, iter,

                                     md_size, key, md_type)) {

            PKCS12err(PKCS12_F_PKCS12_GEN_MAC, PKCS12_R_KEY_GEN_ERROR);

            return 0;

        }

    } else

        if (!(*pkcs12_key_gen)(pass, passlen, salt, saltlen, PKCS12_MAC_ID,

                               iter, md_size, key, md_type)) {

        PKCS12err(PKCS12_F_PKCS12_GEN_MAC, PKCS12_R_KEY_GEN_ERROR);

        return 0;

    }

    if ((hmac = HMAC_CTX_new()) == NULL

        || !HMAC_Init_ex(hmac, key, md_size, md_type, NULL)

        || !HMAC_Update(hmac, p12->authsafes->d.data->data,

                        p12->authsafes->d.data->length)

        || !HMAC_Final(hmac, mac, maclen)) {

        HMAC_CTX_free(hmac);

        return 0;

    }

    HMAC_CTX_free(hmac);

    return 1;

}

int PKCS12_gen_mac(PKCS12 *p12, const char *pass, int passlen,

                   unsigned char *mac, unsigned int *maclen)

{

    return pkcs12_gen_mac(p12, pass, passlen, mac, maclen, NULL);

}

/* Verify the mac */

int PKCS12_verify_mac(PKCS12 *p12, const char *pass, int passlen)

{

    unsigned char mac[EVP_MAX_MD_SIZE];

    unsigned int maclen;

    const ASN1_OCTET_STRING *macoct;

    if (p12->mac == NULL) {

        PKCS12err(PKCS12_F_PKCS12_VERIFY_MAC, PKCS12_R_MAC_ABSENT);

        return 0;

    }

    if (!pkcs12_gen_mac(p12, pass, passlen, mac, &maclen,

                        PKCS12_key_gen_utf8)) {

        PKCS12err(PKCS12_F_PKCS12_VERIFY_MAC, PKCS12_R_MAC_GENERATION_ERROR);

        return 0;

    }

    X509_SIG_get0(p12->mac->dinfo, NULL, &macoct);

    if ((maclen != (unsigned int)ASN1_STRING_length(macoct))

        || CRYPTO_memcmp(mac, ASN1_STRING_get0_data(macoct), maclen) != 0)

        return 0;

    return 1;

}

/* Set a mac */

int PKCS12_set_mac(PKCS12 *p12, const char *pass, int passlen,

                   unsigned char *salt, int saltlen, int iter,

                   const EVP_MD *md_type)

{

    unsigned char mac[EVP_MAX_MD_SIZE];

    unsigned int maclen;

    ASN1_OCTET_STRING *macoct;

    if (!md_type)

        md_type = EVP_sha1();

    if (PKCS12_setup_mac(p12, iter, salt, saltlen, md_type) == PKCS12_ERROR) {

        PKCS12err(PKCS12_F_PKCS12_SET_MAC, PKCS12_R_MAC_SETUP_ERROR);

        return 0;

    }

    /*

     * Note that output mac is forced to UTF-8...

     */

    if (!pkcs12_gen_mac(p12, pass, passlen, mac, &maclen,

                        PKCS12_key_gen_utf8)) {

        PKCS12err(PKCS12_F_PKCS12_SET_MAC, PKCS12_R_MAC_GENERATION_ERROR);

        return 0;

    }

    X509_SIG_getm(p12->mac->dinfo, NULL, &macoct);

    if (!ASN1_OCTET_STRING_set(macoct, mac, maclen)) {

        PKCS12err(PKCS12_F_PKCS12_SET_MAC, PKCS12_R_MAC_STRING_SET_ERROR);

        return 0;

    }

    return 1;

}

/* Set up a mac structure */

int PKCS12_setup_mac(PKCS12 *p12, int iter, unsigned char *salt, int saltlen,

                     const EVP_MD *md_type)

{

    X509_ALGOR *macalg;

    PKCS12_MAC_DATA_free(p12->mac);

    p12->mac = NULL;

    if ((p12->mac = PKCS12_MAC_DATA_new()) == NULL)

        return PKCS12_ERROR;

    if (iter > 1) {

        if ((p12->mac->iter = ASN1_INTEGER_new()) == NULL) {

            PKCS12err(PKCS12_F_PKCS12_SETUP_MAC, ERR_R_MALLOC_FAILURE);

            return 0;

        }

        if (!ASN1_INTEGER_set(p12->mac->iter, iter)) {

            PKCS12err(PKCS12_F_PKCS12_SETUP_MAC, ERR_R_MALLOC_FAILURE);

            return 0;

        }

    }

    if (!saltlen)

        saltlen = PKCS12_SALT_LEN;

    if ((p12->mac->salt->data = OPENSSL_malloc(saltlen)) == NULL) {

        PKCS12err(PKCS12_F_PKCS12_SETUP_MAC, ERR_R_MALLOC_FAILURE);

        return 0;

    }

    p12->mac->salt->length = saltlen;

    if (!salt) {

        if (RAND_bytes(p12->mac->salt->data, saltlen) <= 0)

            return 0;

    } else

        memcpy(p12->mac->salt->data, salt, saltlen);

    X509_SIG_getm(p12->mac->dinfo, &macalg, NULL);

    if (!X509_ALGOR_set0(macalg, OBJ_nid2obj(EVP_MD_type(md_type)),

                         V_ASN1_NULL, NULL)) {

        PKCS12err(PKCS12_F_PKCS12_SETUP_MAC, ERR_R_MALLOC_FAILURE);

        return 0;

    }

    return 1;

}