/*

 * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (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/asn1.h>

#include <openssl/objects.h>

#include <openssl/x509.h>

#include <openssl/x509v3.h>

#include <openssl/core_names.h>

#include "crypto/x509.h"

int X509_issuer_and_serial_cmp(const X509 *a, const X509 *b)

{

    int i;

    const X509_CINF *ai, *bi;

    if (b == NULL)

        return a != NULL;

    if (a == NULL)

        return -1;

    ai = &a->cert_info;

    bi = &b->cert_info;

    i = ASN1_INTEGER_cmp(&ai->serialNumber, &bi->serialNumber);

    if (i != 0)

        return i < 0 ? -1 : 1;

    return X509_NAME_cmp(ai->issuer, bi->issuer);

}

#ifndef OPENSSL_NO_MD5

unsigned long X509_issuer_and_serial_hash(X509 *a)

{

    unsigned long ret = 0;

    EVP_MD_CTX *ctx = EVP_MD_CTX_new();

    unsigned char md[16];

    char *f = NULL;

    EVP_MD *digest = NULL;

    if (ctx == NULL)

        goto err;

    f = X509_NAME_oneline(a->cert_info.issuer, NULL, 0);

    if (f == NULL)

        goto err;

    digest = EVP_MD_fetch(a->libctx, SN_md5, a->propq);

    if (digest == NULL)

        goto err;

    if (!EVP_DigestInit_ex(ctx, digest, NULL))

        goto err;

    if (!EVP_DigestUpdate(ctx, (unsigned char *)f, strlen(f)))

        goto err;

    if (!EVP_DigestUpdate

        (ctx, (unsigned char *)a->cert_info.serialNumber.data,

         (unsigned long)a->cert_info.serialNumber.length))

        goto err;

    if (!EVP_DigestFinal_ex(ctx, &(md[0]), NULL))

        goto err;

    ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |

           ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)

        ) & 0xffffffffL;

 err:

    OPENSSL_free(f);

    EVP_MD_free(digest);

    EVP_MD_CTX_free(ctx);

    return ret;

}

#endif

int X509_issuer_name_cmp(const X509 *a, const X509 *b)

{

    return X509_NAME_cmp(a->cert_info.issuer, b->cert_info.issuer);

}

int X509_subject_name_cmp(const X509 *a, const X509 *b)

{

    return X509_NAME_cmp(a->cert_info.subject, b->cert_info.subject);

}

int X509_CRL_cmp(const X509_CRL *a, const X509_CRL *b)

{

    return X509_NAME_cmp(a->crl.issuer, b->crl.issuer);

}

int X509_CRL_match(const X509_CRL *a, const X509_CRL *b)

{

    int rv;

    if ((a->flags & EXFLAG_NO_FINGERPRINT) == 0

            && (b->flags & EXFLAG_NO_FINGERPRINT) == 0)

        rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);

    else

        return -2;

    return rv < 0 ? -1 : rv > 0;

}

X509_NAME *X509_get_issuer_name(const X509 *a)

{

    return a->cert_info.issuer;

}

unsigned long X509_issuer_name_hash(X509 *x)

{

    return X509_NAME_hash_ex(x->cert_info.issuer, NULL, NULL, NULL);

}

#ifndef OPENSSL_NO_MD5

unsigned long X509_issuer_name_hash_old(X509 *x)

{

    return X509_NAME_hash_old(x->cert_info.issuer);

}

#endif

X509_NAME *X509_get_subject_name(const X509 *a)

{

    return a->cert_info.subject;

}

ASN1_INTEGER *X509_get_serialNumber(X509 *a)

{

    return &a->cert_info.serialNumber;

}

const ASN1_INTEGER *X509_get0_serialNumber(const X509 *a)

{

    return &a->cert_info.serialNumber;

}

unsigned long X509_subject_name_hash(X509 *x)

{

    return X509_NAME_hash_ex(x->cert_info.subject, NULL, NULL, NULL);

}

#ifndef OPENSSL_NO_MD5

unsigned long X509_subject_name_hash_old(X509 *x)

{

    return X509_NAME_hash_old(x->cert_info.subject);

}

#endif

/*

 * Compare two certificates: they must be identical for this to work. NB:

 * Although "cmp" operations are generally prototyped to take "const"

 * arguments (eg. for use in STACKs), the way X509 handling is - these

 * operations may involve ensuring the hashes are up-to-date and ensuring

 * certain cert information is cached. So this is the point where the

 * "depth-first" constification tree has to halt with an evil cast.

 */

int X509_cmp(const X509 *a, const X509 *b)

{

    int rv = 0;

    if (a == b) /* for efficiency */

        return 0;

    /* attempt to compute cert hash */

    (void)X509_check_purpose((X509 *)a, -1, 0);

    (void)X509_check_purpose((X509 *)b, -1, 0);

    if ((a->ex_flags & EXFLAG_NO_FINGERPRINT) == 0

            && (b->ex_flags & EXFLAG_NO_FINGERPRINT) == 0)

        rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);

    if (rv != 0)

        return rv < 0 ? -1 : 1;

    /* Check for match against stored encoding too */

    if (!a->cert_info.enc.modified && !b->cert_info.enc.modified) {

        if (a->cert_info.enc.len < b->cert_info.enc.len)

            return -1;

        if (a->cert_info.enc.len > b->cert_info.enc.len)

            return 1;

        rv = memcmp(a->cert_info.enc.enc,

                    b->cert_info.enc.enc, a->cert_info.enc.len);

    }

    return rv < 0 ? -1 : rv > 0;

}

int ossl_x509_add_cert_new(STACK_OF(X509) **p_sk, X509 *cert, int flags)

{

    if (*p_sk == NULL && (*p_sk = sk_X509_new_null()) == NULL) {

        ERR_raise(ERR_LIB_X509, ERR_R_CRYPTO_LIB);

        return 0;

    }

    return X509_add_cert(*p_sk, cert, flags);

}

int X509_add_cert(STACK_OF(X509) *sk, X509 *cert, int flags)

{

    if (sk == NULL) {

        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

    if ((flags & X509_ADD_FLAG_NO_DUP) != 0) {

        /*

         * not using sk_X509_set_cmp_func() and sk_X509_find()

         * because this re-orders the certs on the stack

         */

        int i;

        for (i = 0; i < sk_X509_num(sk); i++) {

            if (X509_cmp(sk_X509_value(sk, i), cert) == 0)

                return 1;

        }

    }

    if ((flags & X509_ADD_FLAG_NO_SS) != 0) {

        int ret = X509_self_signed(cert, 0);

        if (ret != 0)

            return ret > 0 ? 1 : 0;

    }

    if (!sk_X509_insert(sk, cert,

                        (flags & X509_ADD_FLAG_PREPEND) != 0 ? 0 : -1)) {

        ERR_raise(ERR_LIB_X509, ERR_R_CRYPTO_LIB);

        return 0;

    }

    if ((flags & X509_ADD_FLAG_UP_REF) != 0)

        (void)X509_up_ref(cert);

    return 1;

}

int X509_add_certs(STACK_OF(X509) *sk, STACK_OF(X509) *certs, int flags)

/* compiler would allow 'const' for the certs, yet they may get up-ref'ed */

{

    if (sk == NULL) {

        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

    return ossl_x509_add_certs_new(&sk, certs, flags);

}

int ossl_x509_add_certs_new(STACK_OF(X509) **p_sk, STACK_OF(X509) *certs,

                            int flags)

/* compiler would allow 'const' for the certs, yet they may get up-ref'ed */

{

    int n = sk_X509_num(certs /* may be NULL */);

    int i;

    for (i = 0; i < n; i++) {

        int j = (flags & X509_ADD_FLAG_PREPEND) == 0 ? i : n - 1 - i;

        /* if prepend, add certs in reverse order to keep original order */

        if (!ossl_x509_add_cert_new(p_sk, sk_X509_value(certs, j), flags))

            return 0;

    }

    return 1;

}

int X509_NAME_cmp(const X509_NAME *a, const X509_NAME *b)

{

    int ret;

    if (b == NULL)

        return a != NULL;

    if (a == NULL)

        return -1;

    /* Ensure canonical encoding is present and up to date */

    if (a->canon_enc == NULL || a->modified) {

        ret = i2d_X509_NAME((X509_NAME *)a, NULL);

        if (ret < 0)

            return -2;

    }

    if (b->canon_enc == NULL || b->modified) {

        ret = i2d_X509_NAME((X509_NAME *)b, NULL);

        if (ret < 0)

            return -2;

    }

    ret = a->canon_enclen - b->canon_enclen;

    if (ret == 0 && a->canon_enclen == 0)

        return 0;

    if (a->canon_enc == NULL || b->canon_enc == NULL)

        return -2;

    if (ret == 0)

        ret = memcmp(a->canon_enc, b->canon_enc, a->canon_enclen);

    return ret < 0 ? -1 : ret > 0;

}

unsigned long X509_NAME_hash_ex(const X509_NAME *x, OSSL_LIB_CTX *libctx,

                                const char *propq, int *ok)

{

    unsigned long ret = 0;

    unsigned char md[SHA_DIGEST_LENGTH];

    EVP_MD *sha1 = EVP_MD_fetch(libctx, "SHA1", propq);

    /* Make sure X509_NAME structure contains valid cached encoding */

    i2d_X509_NAME(x, NULL);

    if (ok != NULL)

        *ok = 0;

    if (sha1 != NULL

        && EVP_Digest(x->canon_enc, x->canon_enclen, md, NULL, sha1, NULL)) {

        ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |

               ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)

               ) & 0xffffffffL;

        if (ok != NULL)

            *ok = 1;

    }

    EVP_MD_free(sha1);

    return ret;

}

#ifndef OPENSSL_NO_MD5

/*

 * I now DER encode the name and hash it.  Since I cache the DER encoding,

 * this is reasonably efficient.

 */

unsigned long X509_NAME_hash_old(const X509_NAME *x)

{

    EVP_MD *md5 = EVP_MD_fetch(NULL, OSSL_DIGEST_NAME_MD5, "-fips");

    EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();

    unsigned long ret = 0;

    unsigned char md[16];

    if (md5 == NULL || md_ctx == NULL)

        goto end;

    /* Make sure X509_NAME structure contains valid cached encoding */

    i2d_X509_NAME(x, NULL);

    if (EVP_DigestInit_ex(md_ctx, md5, NULL)

        && EVP_DigestUpdate(md_ctx, x->bytes->data, x->bytes->length)

        && EVP_DigestFinal_ex(md_ctx, md, NULL))

        ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |

               ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)

            ) & 0xffffffffL;

 end:

    EVP_MD_CTX_free(md_ctx);

    EVP_MD_free(md5);

    return ret;

}

#endif

/* Search a stack of X509 for a match */

X509 *X509_find_by_issuer_and_serial(STACK_OF(X509) *sk, const X509_NAME *name,

                                     const ASN1_INTEGER *serial)

{

    int i;

    X509 x, *x509 = NULL;

    if (!sk)

        return NULL;

    x.cert_info.serialNumber = *serial;

    x.cert_info.issuer = (X509_NAME *)name; /* won't modify it */

    for (i = 0; i < sk_X509_num(sk); i++) {

        x509 = sk_X509_value(sk, i);

        if (X509_issuer_and_serial_cmp(x509, &x) == 0)

            return x509;

    }

    return NULL;

}

X509 *X509_find_by_subject(STACK_OF(X509) *sk, const X509_NAME *name)

{

    X509 *x509;

    int i;

    for (i = 0; i < sk_X509_num(sk); i++) {

        x509 = sk_X509_value(sk, i);

        if (X509_NAME_cmp(X509_get_subject_name(x509), name) == 0)

            return x509;

    }

    return NULL;

}

EVP_PKEY *X509_get0_pubkey(const X509 *x)

{

    if (x == NULL)

        return NULL;

    return X509_PUBKEY_get0(x->cert_info.key);

}

EVP_PKEY *X509_get_pubkey(X509 *x)

{

    if (x == NULL)

        return NULL;

    return X509_PUBKEY_get(x->cert_info.key);

}

int X509_check_private_key(const X509 *cert, const EVP_PKEY *pkey)

{

    const EVP_PKEY *xk = X509_get0_pubkey(cert);

    if (xk == NULL) {

        ERR_raise(ERR_LIB_X509, X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);

        return 0;

    }

    return ossl_x509_check_private_key(xk, pkey);

}

int ossl_x509_check_private_key(const EVP_PKEY *x, const EVP_PKEY *pkey)

{

    if (x == NULL) {

        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

    switch (EVP_PKEY_eq(x, pkey)) {

    case 1:

        return 1;

    case 0:

        ERR_raise(ERR_LIB_X509, X509_R_KEY_VALUES_MISMATCH);

        return 0;

    case -1:

        ERR_raise(ERR_LIB_X509, X509_R_KEY_TYPE_MISMATCH);

        return 0;

    case -2:

        ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_KEY_TYPE);

        /* fall thru */

    default:

        return 0;

    }

}

/*

 * Check a suite B algorithm is permitted: pass in a public key and the NID

 * of its signature (or 0 if no signature). The pflags is a pointer to a

 * flags field which must contain the suite B verification flags.

 */

#ifndef OPENSSL_NO_EC

static int check_suite_b(EVP_PKEY *pkey, int sign_nid, unsigned long *pflags)

{

    char curve_name[80];

    size_t curve_name_len;

    int curve_nid;

    if (pkey == NULL || !EVP_PKEY_is_a(pkey, "EC"))

        return X509_V_ERR_SUITE_B_INVALID_ALGORITHM;

    if (!EVP_PKEY_get_group_name(pkey, curve_name, sizeof(curve_name),

                                 &curve_name_len))

        return X509_V_ERR_SUITE_B_INVALID_CURVE;

    curve_nid = OBJ_txt2nid(curve_name);

    /* Check curve is consistent with LOS */

    if (curve_nid == NID_secp384r1) { /* P-384 */

        /*

         * Check signature algorithm is consistent with curve.

         */

        if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA384)

            return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;

        if (!(*pflags & X509_V_FLAG_SUITEB_192_LOS))

            return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;

        /* If we encounter P-384 we cannot use P-256 later */

        *pflags &= ~X509_V_FLAG_SUITEB_128_LOS_ONLY;

    } else if (curve_nid == NID_X9_62_prime256v1) { /* P-256 */

        if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA256)

            return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;

        if (!(*pflags & X509_V_FLAG_SUITEB_128_LOS_ONLY))

            return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;

    } else {

        return X509_V_ERR_SUITE_B_INVALID_CURVE;

    }

    return X509_V_OK;

}

int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,

                            unsigned long flags)

{

    int rv, i, sign_nid;

    EVP_PKEY *pk;

    unsigned long tflags = flags;

    if (!(flags & X509_V_FLAG_SUITEB_128_LOS))

        return X509_V_OK;

    /* If no EE certificate passed in must be first in chain */

    if (x == NULL) {

        x = sk_X509_value(chain, 0);

        i = 1;

    } else {

        i = 0;

    }

    pk = X509_get0_pubkey(x);

    /*

     * With DANE-EE(3) success, or DANE-EE(3)/PKIX-EE(1) failure we don't build

     * a chain all, just report trust success or failure, but must also report

     * Suite-B errors if applicable.  This is indicated via a NULL chain

     * pointer.  All we need to do is check the leaf key algorithm.

     */

    if (chain == NULL)

        return check_suite_b(pk, -1, &tflags);

    if (X509_get_version(x) != X509_VERSION_3) {

        rv = X509_V_ERR_SUITE_B_INVALID_VERSION;

        /* Correct error depth */

        i = 0;

        goto end;

    }

    /* Check EE key only */

    rv = check_suite_b(pk, -1, &tflags);

    if (rv != X509_V_OK) {

        /* Correct error depth */

        i = 0;

        goto end;

    }

    for (; i < sk_X509_num(chain); i++) {

        sign_nid = X509_get_signature_nid(x);

        x = sk_X509_value(chain, i);

        if (X509_get_version(x) != X509_VERSION_3) {

            rv = X509_V_ERR_SUITE_B_INVALID_VERSION;

            goto end;

        }

        pk = X509_get0_pubkey(x);

        rv = check_suite_b(pk, sign_nid, &tflags);

        if (rv != X509_V_OK)

            goto end;

    }

    /* Final check: root CA signature */

    rv = check_suite_b(pk, X509_get_signature_nid(x), &tflags);

 end:

    if (rv != X509_V_OK) {

        /* Invalid signature or LOS errors are for previous cert */

        if ((rv == X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM

             || rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED) && i)

            i--;

        /*

         * If we have LOS error and flags changed then we are signing P-384

         * with P-256. Use more meaningful error.

         */

        if (rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED && flags != tflags)

            rv = X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256;

        if (perror_depth)

            *perror_depth = i;

    }

    return rv;

}

int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)

{

    int sign_nid;

    if (!(flags & X509_V_FLAG_SUITEB_128_LOS))

        return X509_V_OK;

    sign_nid = OBJ_obj2nid(crl->crl.sig_alg.algorithm);

    return check_suite_b(pk, sign_nid, &flags);

}

#else

int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,

                            unsigned long flags)

{

    return 0;

}

int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)

{

    return 0;

}

#endif

/*

 * Not strictly speaking an "up_ref" as a STACK doesn't have a reference

 * count but it has the same effect by duping the STACK and upping the ref of

 * each X509 structure.

 */

STACK_OF(X509) *X509_chain_up_ref(STACK_OF(X509) *chain)

{

    STACK_OF(X509) *ret = sk_X509_dup(chain);

    int i;

    if (ret == NULL)

        return NULL;

    for (i = 0; i < sk_X509_num(ret); i++) {

        X509 *x = sk_X509_value(ret, i);

        if (!X509_up_ref(x))

            goto err;

    }

    return ret;

 err:

    while (i-- > 0)

        X509_free(sk_X509_value(ret, i));

    sk_X509_free(ret);

    return NULL;

}