/*

 * Copyright 1995-2023 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 "internal/refcount.h"

#include <openssl/asn1.h>

#include <openssl/objects.h>

#include <openssl/evp.h>

#include <openssl/x509.h>

#include <openssl/x509v3.h>

#include "crypto/asn1.h"

#include "crypto/x509.h"

#include "x509_local.h"

int X509_set_version(X509 *x, long version)

{

    if (x == NULL)

        return 0;

    if (version == X509_get_version(x))

        return 1; /* avoid needless modification even re-allocation */

    if (version == X509_VERSION_1) {

        ASN1_INTEGER_free(x->cert_info.version);

        x->cert_info.version = NULL;

        x->cert_info.enc.modified = 1;

        return 1;

    }

    if (x->cert_info.version == NULL) {

        if ((x->cert_info.version = ASN1_INTEGER_new()) == NULL)

            return 0;

    }

    if (!ASN1_INTEGER_set(x->cert_info.version, version))

        return 0;

    x->cert_info.enc.modified = 1;

    return 1;

}

int X509_set_serialNumber(X509 *x, ASN1_INTEGER *serial)

{

    ASN1_INTEGER *in;

    if (x == NULL)

        return 0;

    in = &x->cert_info.serialNumber;

    if (in != serial)

        return ASN1_STRING_copy(in, serial);

    x->cert_info.enc.modified = 1;

    return 1;

}

int X509_set_issuer_name(X509 *x, const X509_NAME *name)

{

    if (x == NULL || !X509_NAME_set(&x->cert_info.issuer, name))

        return 0;

    x->cert_info.enc.modified = 1;

    return 1;

}

int X509_set_subject_name(X509 *x, const X509_NAME *name)

{

    if (x == NULL || !X509_NAME_set(&x->cert_info.subject, name))

        return 0;

    x->cert_info.enc.modified = 1;

    return 1;

}

int ossl_x509_set1_time(int *modified, ASN1_TIME **ptm, const ASN1_TIME *tm)

{

    ASN1_TIME *new;

    if (*ptm == tm)

        return 1;

    new = ASN1_STRING_dup(tm);

    if (tm != NULL && new == NULL)

        return 0;

    ASN1_TIME_free(*ptm);

    *ptm = new;

    if (modified != NULL)

        *modified = 1;

    return 1;

}

int X509_set1_notBefore(X509 *x, const ASN1_TIME *tm)

{

    if (x == NULL || tm == NULL)

        return 0;

    return ossl_x509_set1_time(&x->cert_info.enc.modified,

                               &x->cert_info.validity.notBefore, tm);

}

int X509_set1_notAfter(X509 *x, const ASN1_TIME *tm)

{

    if (x == NULL || tm == NULL)

        return 0;

    return ossl_x509_set1_time(&x->cert_info.enc.modified,

                               &x->cert_info.validity.notAfter, tm);

}

int X509_set_pubkey(X509 *x, EVP_PKEY *pkey)

{

    if (x == NULL)

        return 0;

    if (!X509_PUBKEY_set(&(x->cert_info.key), pkey))

        return 0;

    x->cert_info.enc.modified = 1;

    return 1;

}

int X509_up_ref(X509 *x)

{

    int i;

    if (CRYPTO_UP_REF(&x->references, &i) <= 0)

        return 0;

    REF_PRINT_COUNT("X509", i, x);

    REF_ASSERT_ISNT(i < 2);

    return i > 1;

}

long X509_get_version(const X509 *x)

{

    return ASN1_INTEGER_get(x->cert_info.version);

}

const ASN1_TIME *X509_get0_notBefore(const X509 *x)

{

    return x->cert_info.validity.notBefore;

}

const ASN1_TIME *X509_get0_notAfter(const X509 *x)

{

    return x->cert_info.validity.notAfter;

}

ASN1_TIME *X509_getm_notBefore(const X509 *x)

{

    return x->cert_info.validity.notBefore;

}

ASN1_TIME *X509_getm_notAfter(const X509 *x)

{

    return x->cert_info.validity.notAfter;

}

int X509_get_signature_type(const X509 *x)

{

    return EVP_PKEY_type(OBJ_obj2nid(x->sig_alg.algorithm));

}

X509_PUBKEY *X509_get_X509_PUBKEY(const X509 *x)

{

    return x->cert_info.key;

}

const STACK_OF(X509_EXTENSION) *X509_get0_extensions(const X509 *x)

{

    return x->cert_info.extensions;

}

void X509_get0_uids(const X509 *x, const ASN1_BIT_STRING **piuid,

                    const ASN1_BIT_STRING **psuid)

{

    if (piuid != NULL)

        *piuid = x->cert_info.issuerUID;

    if (psuid != NULL)

        *psuid = x->cert_info.subjectUID;

}

const X509_ALGOR *X509_get0_tbs_sigalg(const X509 *x)

{

    return &x->cert_info.signature;

}

int X509_SIG_INFO_get(const X509_SIG_INFO *siginf, int *mdnid, int *pknid,

                      int *secbits, uint32_t *flags)

{

    if (mdnid != NULL)

        *mdnid = siginf->mdnid;

    if (pknid != NULL)

        *pknid = siginf->pknid;

    if (secbits != NULL)

        *secbits = siginf->secbits;

    if (flags != NULL)

        *flags = siginf->flags;

    return (siginf->flags & X509_SIG_INFO_VALID) != 0;

}

void X509_SIG_INFO_set(X509_SIG_INFO *siginf, int mdnid, int pknid,

                       int secbits, uint32_t flags)

{

    siginf->mdnid = mdnid;

    siginf->pknid = pknid;

    siginf->secbits = secbits;

    siginf->flags = flags;

}

int X509_get_signature_info(X509 *x, int *mdnid, int *pknid, int *secbits,

                            uint32_t *flags)

{

    X509_check_purpose(x, -1, -1);

    return X509_SIG_INFO_get(&x->siginf, mdnid, pknid, secbits, flags);

}

/* Modify *siginf according to alg and sig. Return 1 on success, else 0. */

static int x509_sig_info_init(X509_SIG_INFO *siginf, const X509_ALGOR *alg,

                              const ASN1_STRING *sig, const EVP_PKEY *pubkey)

{

    int pknid, mdnid;

    const EVP_MD *md;

    const EVP_PKEY_ASN1_METHOD *ameth;

    siginf->mdnid = NID_undef;

    siginf->pknid = NID_undef;

    siginf->secbits = -1;

    siginf->flags = 0;

    if (!OBJ_find_sigid_algs(OBJ_obj2nid(alg->algorithm), &mdnid, &pknid)

            || pknid == NID_undef) {

        ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_SIGID_ALGS);

        return 0;

    }

    siginf->mdnid = mdnid;

    siginf->pknid = pknid;

    switch (mdnid) {

    case NID_undef:

        /* If we have one, use a custom handler for this algorithm */

        ameth = EVP_PKEY_asn1_find(NULL, pknid);

        if (ameth != NULL && ameth->siginf_set != NULL

                && ameth->siginf_set(siginf, alg, sig))

           break;

        if (pubkey != NULL) {

            int secbits;

            secbits = EVP_PKEY_get_security_bits(pubkey);

            if (secbits != 0) {

                siginf->secbits = secbits;

                break;

            }

        }

        ERR_raise(ERR_LIB_X509, X509_R_ERROR_USING_SIGINF_SET);

        return 0;

        /*

         * SHA1 and MD5 are known to be broken. Reduce security bits so that

         * they're no longer accepted at security level 1.

         * The real values don't really matter as long as they're lower than 80,

         * which is our security level 1.

         */

    case NID_sha1:

        /*

         * https://eprint.iacr.org/2020/014 puts a chosen-prefix attack

         * for SHA1 at2^63.4

         */

        siginf->secbits = 63;

        break;

    case NID_md5:

        /*

         * https://documents.epfl.ch/users/l/le/lenstra/public/papers/lat.pdf

         * puts a chosen-prefix attack for MD5 at 2^39.

         */

        siginf->secbits = 39;

        break;

    case NID_id_GostR3411_94:

        /*

         * There is a collision attack on GOST R 34.11-94 at 2^105, see

         * https://link.springer.com/chapter/10.1007%2F978-3-540-85174-5_10

         */

        siginf->secbits = 105;

        break;

    default:

        /* Security bits: half number of bits in digest */

        if ((md = EVP_get_digestbynid(mdnid)) == NULL) {

            ERR_raise(ERR_LIB_X509, X509_R_ERROR_GETTING_MD_BY_NID);

            return 0;

        }

        siginf->secbits = EVP_MD_get_size(md) * 4;

        break;

    }

    switch (mdnid) {

    case NID_sha1:

    case NID_sha256:

    case NID_sha384:

    case NID_sha512:

        siginf->flags |= X509_SIG_INFO_TLS;

    }

    siginf->flags |= X509_SIG_INFO_VALID;

    return 1;

}

/* Returns 1 on success, 0 on failure */

int ossl_x509_init_sig_info(X509 *x)

{

    return x509_sig_info_init(&x->siginf, &x->sig_alg, &x->signature,

                              X509_PUBKEY_get0(x->cert_info.key));

}