/* crypto/x509/x509_cmp.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <ctype.h>
#include "cryptlib.h"
#include <openssl/asn1.h>
#include <openssl/objects.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>

int X509_issuer_and_serial_cmp(const X509 *a, const X509 *b)
{
    int i;
    X509_CINF *ai, *bi;

    ai = a->cert_info;
    bi = b->cert_info;
    i = M_ASN1_INTEGER_cmp(ai->serialNumber, bi->serialNumber);
    if (i)
        return (i);
    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;
    unsigned char md[16];
    char *f;

    EVP_MD_CTX_init(&ctx);
    f = X509_NAME_oneline(a->cert_info->issuer, NULL, 0);
    ret = strlen(f);
    EVP_DigestInit_ex(&ctx, EVP_md5(), NULL);
    EVP_DigestUpdate(&ctx, (unsigned char *)f, ret);
    OPENSSL_free(f);
    EVP_DigestUpdate(&ctx, (unsigned char *)a->cert_info->serialNumber->data,
                     (unsigned long)a->cert_info->serialNumber->length);
    EVP_DigestFinal_ex(&ctx, &(md[0]), NULL);
    ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
           ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
        ) & 0xffffffffL;
    EVP_MD_CTX_cleanup(&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));
}

X509_NAME *X509_get_issuer_name(X509 *a)
{
    return (a->cert_info->issuer);
}

unsigned long X509_issuer_name_hash(X509 *x)
{
    return (X509_NAME_hash(x->cert_info->issuer));
}

X509_NAME *X509_get_subject_name(X509 *a)
{
    return (a->cert_info->subject);
}

ASN1_INTEGER *X509_get_serialNumber(X509 *a)
{
    return (a->cert_info->serialNumber);
}

unsigned long X509_subject_name_hash(X509 *x)
{
    return (X509_NAME_hash(x->cert_info->subject));
}

#ifndef OPENSSL_NO_SHA
/*
 * 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)
{
    /* ensure hash is valid */
    X509_check_purpose((X509 *)a, -1, 0);
    X509_check_purpose((X509 *)b, -1, 0);

    return memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
}
#endif

/* Case insensitive string comparision */
static int nocase_cmp(const ASN1_STRING *a, const ASN1_STRING *b)
{
    int i;

    if (a->length != b->length)
        return (a->length - b->length);

    for (i = 0; i < a->length; i++) {
        int ca, cb;

        ca = tolower(a->data[i]);
        cb = tolower(b->data[i]);

        if (ca != cb)
            return (ca - cb);
    }
    return 0;
}

/*
 * Case insensitive string comparision with space normalization Space
 * normalization - ignore leading, trailing spaces, multiple spaces between
 * characters are replaced by single space
 */
static int nocase_spacenorm_cmp(const ASN1_STRING *a, const ASN1_STRING *b)
{
    unsigned char *pa = NULL, *pb = NULL;
    int la, lb;

    la = a->length;
    lb = b->length;
    pa = a->data;
    pb = b->data;

    /* skip leading spaces */
    while (la > 0 && isspace(*pa)) {
        la--;
        pa++;
    }
    while (lb > 0 && isspace(*pb)) {
        lb--;
        pb++;
    }

    /* skip trailing spaces */
    while (la > 0 && isspace(pa[la - 1]))
        la--;
    while (lb > 0 && isspace(pb[lb - 1]))
        lb--;

    /* compare strings with space normalization */
    while (la > 0 && lb > 0) {
        int ca, cb;

        /* compare character */
        ca = tolower(*pa);
        cb = tolower(*pb);
        if (ca != cb)
            return (ca - cb);

        pa++;
        pb++;
        la--;
        lb--;

        if (la <= 0 || lb <= 0)
            break;

        /* is white space next character ? */
        if (isspace(*pa) && isspace(*pb)) {
            /* skip remaining white spaces */
            while (la > 0 && isspace(*pa)) {
                la--;
                pa++;
            }
            while (lb > 0 && isspace(*pb)) {
                lb--;
                pb++;
            }
        }
    }
    if (la > 0 || lb > 0)
        return la - lb;

    return 0;
}

static int asn1_string_memcmp(ASN1_STRING *a, ASN1_STRING *b)
{
    int j;
    j = a->length - b->length;
    if (j)
        return j;
    return memcmp(a->data, b->data, a->length);
}

#define STR_TYPE_CMP (B_ASN1_PRINTABLESTRING|B_ASN1_T61STRING|B_ASN1_UTF8STRING)

int X509_NAME_cmp(const X509_NAME *a, const X509_NAME *b)
{
    int i, j;
    X509_NAME_ENTRY *na, *nb;

    unsigned long nabit, nbbit;

    j = sk_X509_NAME_ENTRY_num(a->entries)
        - sk_X509_NAME_ENTRY_num(b->entries);
    if (j)
        return j;
    for (i = sk_X509_NAME_ENTRY_num(a->entries) - 1; i >= 0; i--) {
        na = sk_X509_NAME_ENTRY_value(a->entries, i);
        nb = sk_X509_NAME_ENTRY_value(b->entries, i);
        j = na->value->type - nb->value->type;
        if (j) {
            nabit = ASN1_tag2bit(na->value->type);
            nbbit = ASN1_tag2bit(nb->value->type);
            if (!(nabit & STR_TYPE_CMP) || !(nbbit & STR_TYPE_CMP))
                return j;
            if (!asn1_string_memcmp(na->value, nb->value))
                j = 0;
        } else if (na->value->type == V_ASN1_PRINTABLESTRING)
            j = nocase_spacenorm_cmp(na->value, nb->value);
        else if (na->value->type == V_ASN1_IA5STRING
                 && OBJ_obj2nid(na->object) == NID_pkcs9_emailAddress)
            j = nocase_cmp(na->value, nb->value);
        else
            j = asn1_string_memcmp(na->value, nb->value);
        if (j)
            return (j);
        j = na->set - nb->set;
        if (j)
            return (j);
    }

    /*
     * We will check the object types after checking the values since the
     * values will more often be different than the object types.
     */
    for (i = sk_X509_NAME_ENTRY_num(a->entries) - 1; i >= 0; i--) {
        na = sk_X509_NAME_ENTRY_value(a->entries, i);
        nb = sk_X509_NAME_ENTRY_value(b->entries, i);
        j = OBJ_cmp(na->object, nb->object);
        if (j)
            return (j);
    }
    return (0);
}

#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(X509_NAME *x)
{
    unsigned long ret = 0;
    unsigned char md[16];
    EVP_MD_CTX md_ctx;

    /* Make sure X509_NAME structure contains valid cached encoding */
    i2d_X509_NAME(x, NULL);
    EVP_MD_CTX_init(&md_ctx);
    EVP_MD_CTX_set_flags(&md_ctx, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
    EVP_DigestInit_ex(&md_ctx, EVP_md5(), NULL);
    EVP_DigestUpdate(&md_ctx, x->bytes->data, x->bytes->length);
    EVP_DigestFinal_ex(&md_ctx, md, NULL);
    EVP_MD_CTX_cleanup(&md_ctx);

    ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
           ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
        ) & 0xffffffffL;
    return (ret);
}
#endif

/* Search a stack of X509 for a match */
X509 *X509_find_by_issuer_and_serial(STACK_OF(X509) *sk, X509_NAME *name,
                                     ASN1_INTEGER *serial)
{
    int i;
    X509_CINF cinf;
    X509 x, *x509 = NULL;

    if (!sk)
        return NULL;

    x.cert_info = &cinf;
    cinf.serialNumber = serial;
    cinf.issuer = name;

    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, 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_get_pubkey(X509 *x)
{
    if ((x == NULL) || (x->cert_info == NULL))
        return (NULL);
    return (X509_PUBKEY_get(x->cert_info->key));
}

ASN1_BIT_STRING *X509_get0_pubkey_bitstr(const X509 *x)
{
    if (!x)
        return NULL;
    return x->cert_info->key->public_key;
}

int X509_check_private_key(X509 *x, EVP_PKEY *k)
{
    EVP_PKEY *xk = NULL;
    int ok = 0;

    xk = X509_get_pubkey(x);
    switch (EVP_PKEY_cmp(xk, k)) {
    case 1:
        ok = 1;
        break;
    case 0:
        X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_KEY_VALUES_MISMATCH);
        break;
    case -1:
        X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_KEY_TYPE_MISMATCH);
        break;
    case -2:
#ifndef OPENSSL_NO_EC
        if (k->type == EVP_PKEY_EC) {
            X509err(X509_F_X509_CHECK_PRIVATE_KEY, ERR_R_EC_LIB);
            break;
        }
#endif
#ifndef OPENSSL_NO_DH
        if (k->type == EVP_PKEY_DH) {
            /* No idea */
            X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_CANT_CHECK_DH_KEY);
            break;
        }
#endif
        X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_UNKNOWN_KEY_TYPE);
    }

    EVP_PKEY_free(xk);
    return (ok);
}