Fix X509_STORE_CTX_init. Make indentation more consistent. Dump core less often.

[thirdparty/openssl.git] / crypto / x509 / x509_vfy.c

/* crypto/x509/x509_vfy.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 <time.h>
#include <errno.h>

#include "cryptlib.h"
#include <openssl/crypto.h>
#include <openssl/lhash.h>
#include <openssl/buffer.h>
#include <openssl/evp.h>
#include <openssl/asn1.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include <openssl/objects.h>

static int null_callback(int ok,X509_STORE_CTX *e);
static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
static int check_chain_purpose(X509_STORE_CTX *ctx);
static int check_trust(X509_STORE_CTX *ctx);
static int internal_verify(X509_STORE_CTX *ctx);
const char *X509_version="X.509" OPENSSL_VERSION_PTEXT;

static STACK_OF(CRYPTO_EX_DATA_FUNCS) *x509_store_ctx_method=NULL;
static int x509_store_ctx_num=0;
#if 0
static int x509_store_num=1;
static STACK *x509_store_method=NULL;
#endif

static int null_callback(int ok, X509_STORE_CTX *e)
        {
        return(ok);
        }

#if 0
static int x509_subject_cmp(X509 **a, X509 **b)
        {
        return(X509_subject_name_cmp(*a,*b));
        }
#endif

int X509_verify_cert(X509_STORE_CTX *ctx)
        {
        X509 *x,*xtmp,*chain_ss=NULL;
        X509_NAME *xn;
        int depth,i,ok=0;
        int num;
        int (*cb)();
        STACK_OF(X509) *sktmp=NULL;

        if (ctx->cert == NULL)
                {
                X509err(X509_F_X509_VERIFY_CERT,X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
                return(-1);
                }

        cb=ctx->verify_cb;
        if (cb == NULL) cb=null_callback;

        /* first we make sure the chain we are going to build is
         * present and that the first entry is in place */
        if (ctx->chain == NULL)
                {
                if (    ((ctx->chain=sk_X509_new_null()) == NULL) ||
                        (!sk_X509_push(ctx->chain,ctx->cert)))
                        {
                        X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
                        goto end;
                        }
                CRYPTO_add(&ctx->cert->references,1,CRYPTO_LOCK_X509);
                ctx->last_untrusted=1;
                }

        /* We use a temporary STACK so we can chop and hack at it */
        if (ctx->untrusted != NULL
            && (sktmp=sk_X509_dup(ctx->untrusted)) == NULL)
                {
                X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
                goto end;
                }

        num=sk_X509_num(ctx->chain);
        x=sk_X509_value(ctx->chain,num-1);
        depth=ctx->depth;


        for (;;)
                {
                /* If we have enough, we break */
                if (depth < num) break; /* FIXME: If this happens, we should take
                                         * note of it and, if appropriate, use the
                                         * X509_V_ERR_CERT_CHAIN_TOO_LONG error
                                         * code later.
                                         */

                /* If we are self signed, we break */
                xn=X509_get_issuer_name(x);
                if (ctx->check_issued(ctx, x,x)) break;

                /* If we were passed a cert chain, use it first */
                if (ctx->untrusted != NULL)
                        {
                        xtmp=find_issuer(ctx, sktmp,x);
                        if (xtmp != NULL)
                                {
                                if (!sk_X509_push(ctx->chain,xtmp))
                                        {
                                        X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
                                        goto end;
                                        }
                                CRYPTO_add(&xtmp->references,1,CRYPTO_LOCK_X509);
                                sk_X509_delete_ptr(sktmp,xtmp);
                                ctx->last_untrusted++;
                                x=xtmp;
                                num++;
                                /* reparse the full chain for
                                 * the next one */
                                continue;
                                }
                        }
                break;
                }

        /* at this point, chain should contain a list of untrusted
         * certificates.  We now need to add at least one trusted one,
         * if possible, otherwise we complain. */

        /* Examine last certificate in chain and see if it
         * is self signed.
         */

        i=sk_X509_num(ctx->chain);
        x=sk_X509_value(ctx->chain,i-1);
        xn = X509_get_subject_name(x);
        if (ctx->check_issued(ctx, x, x))
                {
                /* we have a self signed certificate */
                if (sk_X509_num(ctx->chain) == 1)
                        {
                        /* We have a single self signed certificate: see if
                         * we can find it in the store. We must have an exact
                         * match to avoid possible impersonation.
                         */
                        ok = ctx->get_issuer(&xtmp, ctx, x);
                        if ((ok <= 0) || X509_cmp(x, xtmp)) 
                                {
                                ctx->error=X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;
                                ctx->current_cert=x;
                                ctx->error_depth=i-1;
                                if(ok == 1) X509_free(xtmp);
                                ok=cb(0,ctx);
                                if (!ok) goto end;
                                }
                        else 
                                {
                                /* We have a match: replace certificate with store version
                                 * so we get any trust settings.
                                 */
                                X509_free(x);
                                x = xtmp;
                                sk_X509_set(ctx->chain, i - 1, x);
                                ctx->last_untrusted=0;
                                }
                        }
                else
                        {
                        /* extract and save self signed certificate for later use */
                        chain_ss=sk_X509_pop(ctx->chain);
                        ctx->last_untrusted--;
                        num--;
                        x=sk_X509_value(ctx->chain,num-1);
                        }
                }

        /* We now lookup certs from the certificate store */
        for (;;)
                {
                /* If we have enough, we break */
                if (depth < num) break;

                /* If we are self signed, we break */
                xn=X509_get_issuer_name(x);
                if (ctx->check_issued(ctx,x,x)) break;

                ok = ctx->get_issuer(&xtmp, ctx, x);

                if (ok < 0) return ok;
                if(ok == 0) break;

                x = xtmp;
                if (!sk_X509_push(ctx->chain,x))
                        {
                        X509_free(xtmp);
                        X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
                        return(0);
                        }
                num++;
                }

        /* we now have our chain, lets check it... */
        xn=X509_get_issuer_name(x);

        /* Is last certificate looked up self signed? */
        if (!ctx->check_issued(ctx,x,x))
                {
                if ((chain_ss == NULL) || !ctx->check_issued(ctx, x, chain_ss))
                        {
                        if (ctx->last_untrusted >= num)
                                ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY;
                        else
                                ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT;
                        ctx->current_cert=x;
                        }
                else
                        {

                        sk_X509_push(ctx->chain,chain_ss);
                        num++;
                        ctx->last_untrusted=num;
                        ctx->current_cert=chain_ss;
                        ctx->error=X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN;
                        chain_ss=NULL;
                        }

                ctx->error_depth=num-1;
                ok=cb(0,ctx);
                if (!ok) goto end;
                }

        /* We have the chain complete: now we need to check its purpose */
        if(ctx->purpose > 0) ok = check_chain_purpose(ctx);

        if(!ok) goto end;

        /* The chain extensions are OK: check trust */

        if(ctx->trust > 0) ok = check_trust(ctx);

        if(!ok) goto end;

        /* We may as well copy down any DSA parameters that are required */
        X509_get_pubkey_parameters(NULL,ctx->chain);

        /* At this point, we have a chain and just need to verify it */
        if (ctx->verify != NULL)
                ok=ctx->verify(ctx);
        else
                ok=internal_verify(ctx);
        if (0)
                {
end:
                X509_get_pubkey_parameters(NULL,ctx->chain);
                }
        if (sktmp != NULL) sk_X509_free(sktmp);
        if (chain_ss != NULL) X509_free(chain_ss);
        return(ok);
        }


/* Given a STACK_OF(X509) find the issuer of cert (if any)
 */

static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
{
        int i;
        X509 *issuer;
        for(i = 0; i < sk_X509_num(sk); i++)
                {
                issuer = sk_X509_value(sk, i);
                if(ctx->check_issued(ctx, x, issuer))
                        return issuer;
                }
        return NULL;
}

/* Given a possible certificate and issuer check them */

static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
{
        int ret;
        ret = X509_check_issued(issuer, x);
        if (ret == X509_V_OK)
                return 1;
        else
                {
                ctx->error = ret;
                ctx->current_cert = x;
                ctx->current_issuer = issuer;
                if ((ctx->flags & X509_V_FLAG_CB_ISSUER_CHECK) && ctx->verify_cb)
                        return ctx->verify_cb(0, ctx);
                else
                        return 0;
                }
        return 0;
}

/* Alternative lookup method: look from a STACK stored in other_ctx */

static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
{
        *issuer = find_issuer(ctx, ctx->other_ctx, x);
        if (*issuer)
                {
                CRYPTO_add(&(*issuer)->references,1,CRYPTO_LOCK_X509);
                return 1;
                }
        else
                return 0;
}
        

/* Check a certificate chains extensions for consistency
 * with the supplied purpose
 */

static int check_chain_purpose(X509_STORE_CTX *ctx)
{
#ifdef NO_CHAIN_VERIFY
        return 1;
#else
        int i, ok=0;
        X509 *x;
        int (*cb)();
        cb=ctx->verify_cb;
        if (cb == NULL) cb=null_callback;
        /* Check all untrusted certificates */
        for(i = 0; i < ctx->last_untrusted; i++)
                {
                x = sk_X509_value(ctx->chain, i);
                if (!X509_check_purpose(x, ctx->purpose, i))
                        {
                        if (i)
                                ctx->error = X509_V_ERR_INVALID_CA;
                        else
                                ctx->error = X509_V_ERR_INVALID_PURPOSE;
                        ctx->error_depth = i;
                        ctx->current_cert = x;
                        ok=cb(0,ctx);
                        if (!ok) goto end;
                        }
                /* Check pathlen */
                if((i > 1) && (x->ex_pathlen != -1)
                           && (i > (x->ex_pathlen + 1)))
                        {
                        ctx->error = X509_V_ERR_PATH_LENGTH_EXCEEDED;
                        ctx->error_depth = i;
                        ctx->current_cert = x;
                        ok=cb(0,ctx);
                        if (!ok) goto end;
                        }
                }
        ok = 1;
 end:
        return(ok);
#endif
}

static int check_trust(X509_STORE_CTX *ctx)
{
#ifdef NO_CHAIN_VERIFY
        return 1;
#else
        int i, ok;
        X509 *x;
        int (*cb)();
        cb=ctx->verify_cb;
        if (cb == NULL) cb=null_callback;
/* For now just check the last certificate in the chain */
        i = sk_X509_num(ctx->chain) - 1;
        x = sk_X509_value(ctx->chain, i);
        ok = X509_check_trust(x, ctx->trust, 0);
        if (ok == X509_TRUST_TRUSTED)
                return 1;
        ctx->error_depth = sk_X509_num(ctx->chain) - 1;
        ctx->current_cert = x;
        if (ok == X509_TRUST_REJECTED)
                ctx->error = X509_V_ERR_CERT_REJECTED;
        else
                ctx->error = X509_V_ERR_CERT_UNTRUSTED;
        ok = cb(0, ctx);
        return(ok);
#endif
}

static int internal_verify(X509_STORE_CTX *ctx)
        {
        int i,ok=0,n;
        X509 *xs,*xi;
        EVP_PKEY *pkey=NULL;
        time_t *ptime;
        int (*cb)();

        cb=ctx->verify_cb;
        if (cb == NULL) cb=null_callback;

        n=sk_X509_num(ctx->chain);
        ctx->error_depth=n-1;
        n--;
        xi=sk_X509_value(ctx->chain,n);
        if (ctx->flags & X509_V_FLAG_USE_CHECK_TIME)
                ptime = &ctx->check_time;
        else
                ptime = NULL;
        if (ctx->check_issued(ctx, xi, xi))
                xs=xi;
        else
                {
                if (n <= 0)
                        {
                        ctx->error=X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;
                        ctx->current_cert=xi;
                        ok=cb(0,ctx);
                        goto end;
                        }
                else
                        {
                        n--;
                        ctx->error_depth=n;
                        xs=sk_X509_value(ctx->chain,n);
                        }
                }

/*      ctx->error=0;  not needed */
        while (n >= 0)
                {
                ctx->error_depth=n;
                if (!xs->valid)
                        {
                        if ((pkey=X509_get_pubkey(xi)) == NULL)
                                {
                                ctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
                                ctx->current_cert=xi;
                                ok=(*cb)(0,ctx);
                                if (!ok) goto end;
                                }
                        if (X509_verify(xs,pkey) <= 0)
                                {
                                ctx->error=X509_V_ERR_CERT_SIGNATURE_FAILURE;
                                ctx->current_cert=xs;
                                ok=(*cb)(0,ctx);
                                if (!ok)
                                        {
                                        EVP_PKEY_free(pkey);
                                        goto end;
                                        }
                                }
                        EVP_PKEY_free(pkey);
                        pkey=NULL;

                        i=X509_cmp_time(X509_get_notBefore(xs), ptime);
                        if (i == 0)
                                {
                                ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD;
                                ctx->current_cert=xs;
                                ok=(*cb)(0,ctx);
                                if (!ok) goto end;
                                }
                        if (i > 0)
                                {
                                ctx->error=X509_V_ERR_CERT_NOT_YET_VALID;
                                ctx->current_cert=xs;
                                ok=(*cb)(0,ctx);
                                if (!ok) goto end;
                                }
                        xs->valid=1;
                        }

                i=X509_cmp_time(X509_get_notAfter(xs), ptime);
                if (i == 0)
                        {
                        ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD;
                        ctx->current_cert=xs;
                        ok=(*cb)(0,ctx);
                        if (!ok) goto end;
                        }

                if (i < 0)
                        {
                        ctx->error=X509_V_ERR_CERT_HAS_EXPIRED;
                        ctx->current_cert=xs;
                        ok=(*cb)(0,ctx);
                        if (!ok) goto end;
                        }

                /* CRL CHECK */

                /* The last error (if any) is still in the error value */
                ctx->current_cert=xs;
                ok=(*cb)(1,ctx);
                if (!ok) goto end;

                n--;
                if (n >= 0)
                        {
                        xi=xs;
                        xs=sk_X509_value(ctx->chain,n);
                        }
                }
        ok=1;
end:
        return(ok);
        }

int X509_cmp_current_time(ASN1_TIME *ctm)
{
        return X509_cmp_time(ctm, NULL);
}

int X509_cmp_time(ASN1_TIME *ctm, time_t *cmp_time)
        {
        char *str;
        ASN1_TIME atm;
        time_t offset;
        char buff1[24],buff2[24],*p;
        int i,j;

        p=buff1;
        i=ctm->length;
        str=(char *)ctm->data;
        if (ctm->type == V_ASN1_UTCTIME)
                {
                if ((i < 11) || (i > 17)) return(0);
                memcpy(p,str,10);
                p+=10;
                str+=10;
                }
        else
                {
                if (i < 13) return 0;
                memcpy(p,str,12);
                p+=12;
                str+=12;
                }

        if ((*str == 'Z') || (*str == '-') || (*str == '+'))
                { *(p++)='0'; *(p++)='0'; }
        else
                { 
                *(p++)= *(str++);
                *(p++)= *(str++);
                /* Skip any fractional seconds... */
                if (*str == '.')
                        {
                        str++;
                        while((*str >= '0') && (*str <= '9')) str++;
                        }
                
                }
        *(p++)='Z';
        *(p++)='\0';

        if (*str == 'Z')
                offset=0;
        else
                {
                if ((*str != '+') && (str[5] != '-'))
                        return(0);
                offset=((str[1]-'0')*10+(str[2]-'0'))*60;
                offset+=(str[3]-'0')*10+(str[4]-'0');
                if (*str == '-')
                        offset= -offset;
                }
        atm.type=ctm->type;
        atm.length=sizeof(buff2);
        atm.data=(unsigned char *)buff2;

        X509_time_adj(&atm,-offset*60, cmp_time);

        if(ctm->type == V_ASN1_UTCTIME)
                {
                i=(buff1[0]-'0')*10+(buff1[1]-'0');
                if (i < 50) i+=100; /* cf. RFC 2459 */
                j=(buff2[0]-'0')*10+(buff2[1]-'0');
                if (j < 50) j+=100;

                if (i < j) return (-1);
                if (i > j) return (1);
                }
        i=strcmp(buff1,buff2);
        if (i == 0) /* wait a second then return younger :-) */
                return(-1);
        else
                return(i);
        }

ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
{
        return X509_time_adj(s, adj, NULL);
}

ASN1_TIME *X509_time_adj(ASN1_TIME *s, long adj, time_t *in_tm)
        {
        time_t t;

        if(in_tm) t = *in_tm;
        else time(&t);

        t+=adj;
        if(!s) return ASN1_TIME_set(s, t);
        if(s->type == V_ASN1_UTCTIME) return(ASN1_UTCTIME_set(s,t));
        return ASN1_GENERALIZEDTIME_set(s, t);
        }

int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
        {
        EVP_PKEY *ktmp=NULL,*ktmp2;
        int i,j;

        if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey)) return(1);

        for (i=0; i<sk_X509_num(chain); i++)
                {
                ktmp=X509_get_pubkey(sk_X509_value(chain,i));
                if (ktmp == NULL)
                        {
                        X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
                        return(0);
                        }
                if (!EVP_PKEY_missing_parameters(ktmp))
                        break;
                else
                        {
                        EVP_PKEY_free(ktmp);
                        ktmp=NULL;
                        }
                }
        if (ktmp == NULL)
                {
                X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
                return(0);
                }

        /* first, populate the other certs */
        for (j=i-1; j >= 0; j--)
                {
                ktmp2=X509_get_pubkey(sk_X509_value(chain,j));
                EVP_PKEY_copy_parameters(ktmp2,ktmp);
                EVP_PKEY_free(ktmp2);
                }
        
        if (pkey != NULL) EVP_PKEY_copy_parameters(pkey,ktmp);
        EVP_PKEY_free(ktmp);
        return(1);
        }

int X509_STORE_CTX_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
             CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
        {
        x509_store_ctx_num++;
        return(CRYPTO_get_ex_new_index(x509_store_ctx_num-1,
                &x509_store_ctx_method,
                argl,argp,new_func,dup_func,free_func));
        }

int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
        {
        return(CRYPTO_set_ex_data(&ctx->ex_data,idx,data));
        }

void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
        {
        return(CRYPTO_get_ex_data(&ctx->ex_data,idx));
        }

int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
        {
        return(ctx->error);
        }

void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
        {
        ctx->error=err;
        }

int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
        {
        return(ctx->error_depth);
        }

X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
        {
        return(ctx->current_cert);
        }

STACK_OF(X509) *X509_STORE_CTX_get_chain(X509_STORE_CTX *ctx)
        {
        return(ctx->chain);
        }

STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
        {
        int i;
        X509 *x;
        STACK_OF(X509) *chain;
        if(!ctx->chain || !(chain = sk_X509_dup(ctx->chain))) return NULL;
        for(i = 0; i < sk_X509_num(chain); i++)
                {
                x = sk_X509_value(chain, i);
                CRYPTO_add(&x->references, 1, CRYPTO_LOCK_X509);
                }
        return(chain);
        }

void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
        {
        ctx->cert=x;
        }

void X509_STORE_CTX_set_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
        {
        ctx->untrusted=sk;
        }

int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
        {
        return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
        }

int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
        {
        return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
        }

/* This function is used to set the X509_STORE_CTX purpose and trust
 * values. This is intended to be used when another structure has its
 * own trust and purpose values which (if set) will be inherited by
 * the ctx. If they aren't set then we will usually have a default
 * purpose in mind which should then be used to set the trust value.
 * An example of this is SSL use: an SSL structure will have its own
 * purpose and trust settings which the application can set: if they
 * aren't set then we use the default of SSL client/server.
 */

int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
                                int purpose, int trust)
{
        int idx;
        /* If purpose not set use default */
        if (!purpose) purpose = def_purpose;
        /* If we have a purpose then check it is valid */
        if (purpose)
                {
                X509_PURPOSE *ptmp;
                idx = X509_PURPOSE_get_by_id(purpose);
                if(idx == -1)
                        {
                        X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
                                                X509_R_UNKNOWN_PURPOSE_ID);
                        return 0;
                        }
                ptmp = X509_PURPOSE_get0(idx);
                if(ptmp->trust == X509_TRUST_DEFAULT)
                        {
                        idx = X509_PURPOSE_get_by_id(def_purpose);
                        if(idx == -1)
                                {
                                X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
                                                X509_R_UNKNOWN_PURPOSE_ID);
                                return 0;
                                }
                        ptmp = X509_PURPOSE_get0(idx);
                        }
                /* If trust not set then get from purpose default */
                if(!trust) trust = ptmp->trust;
                }
        if(trust)
                {
                idx = X509_TRUST_get_by_id(trust);
                if(idx == -1)
                        {
                        X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
                                                X509_R_UNKNOWN_TRUST_ID);
                        return 0;
                        }
                }

        if(purpose) ctx->purpose = purpose;
        if(trust) ctx->trust = trust;
        return 1;
}

X509_STORE_CTX *X509_STORE_CTX_new(void)
{
        X509_STORE_CTX *ctx;
        ctx = (X509_STORE_CTX *)OPENSSL_malloc(sizeof(X509_STORE_CTX));
        if (ctx) memset(ctx, 0, sizeof(X509_STORE_CTX));
        return ctx;
}

void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
{
        X509_STORE_CTX_cleanup(ctx);
        OPENSSL_free(ctx);
}

void X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
             STACK_OF(X509) *chain)
        {
        ctx->ctx=store;
        ctx->current_method=0;
        ctx->cert=x509;
        ctx->untrusted=chain;
        ctx->last_untrusted=0;
        ctx->purpose=0;
        ctx->trust=0;
        ctx->check_time=0;
        ctx->flags=0;
        ctx->other_ctx=NULL;
        ctx->valid=0;
        ctx->chain=NULL;
        ctx->depth=9;
        ctx->error=0;
        ctx->error_depth=0;
        ctx->current_cert=NULL;
        ctx->current_issuer=NULL;
        ctx->check_issued = check_issued;
        ctx->get_issuer = X509_STORE_CTX_get1_issuer;
        ctx->verify_cb = store->verify_cb;
        ctx->verify = store->verify;
        ctx->cleanup = 0;
        memset(&(ctx->ex_data),0,sizeof(CRYPTO_EX_DATA));
        }

/* Set alternative lookup method: just a STACK of trusted certificates.
 * This avoids X509_STORE nastiness where it isn't needed.
 */

void X509_STORE_CTX_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
{
        ctx->other_ctx = sk;
        ctx->get_issuer = get_issuer_sk;
}

void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
        {
        if(ctx->cleanup) ctx->cleanup(ctx);
        if (ctx->chain != NULL)
                {
                sk_X509_pop_free(ctx->chain,X509_free);
                ctx->chain=NULL;
                }
        CRYPTO_free_ex_data(x509_store_ctx_method,ctx,&(ctx->ex_data));
        memset(&ctx->ex_data,0,sizeof(CRYPTO_EX_DATA));
        }

void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, long flags)
        {
                ctx->flags |= flags;
        }

void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, long flags, time_t t)
        {
                ctx->check_time = t;
                ctx->flags |= X509_V_FLAG_USE_CHECK_TIME;
        }

IMPLEMENT_STACK_OF(X509)
IMPLEMENT_ASN1_SET_OF(X509)

IMPLEMENT_STACK_OF(X509_NAME)

IMPLEMENT_STACK_OF(X509_ATTRIBUTE)
IMPLEMENT_ASN1_SET_OF(X509_ATTRIBUTE)