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openssl/crypto/x509/x509_vfy.c
Emilia Kasper fa57f74a39 Fix length checks in X509_cmp_time to avoid out-of-bounds reads. 
Also tighten X509_cmp_time to reject more than three fractional
seconds in the time; and to reject trailing garbage after the offset.

CVE-2015-1789

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-06-11 13:07:49 +01:00

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/* 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_extensions(X509_STORE_CTX *ctx);
static int check_trust(X509_STORE_CTX *ctx);
static int check_revocation(X509_STORE_CTX *ctx);
static int check_cert(X509_STORE_CTX *ctx);
static int check_policy(X509_STORE_CTX *ctx);
static int internal_verify(X509_STORE_CTX *ctx);
const char X509_version[] = "X.509" OPENSSL_VERSION_PTEXT;
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;
int bad_chain = 0;
X509_VERIFY_PARAM *param = ctx->param;
int depth, i, ok = 0;
int num;
int (*cb) (int xok, X509_STORE_CTX *xctx);
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;
/*
* 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 = param->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 */
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);
(void)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);
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);
bad_chain = 1;
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;
(void)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 */
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... */
/* 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;
bad_chain = 1;
ok = cb(0, ctx);
if (!ok)
goto end;
}
/* We have the chain complete: now we need to check its purpose */
ok = check_chain_extensions(ctx);
if (!ok)
goto end;
/* The chain extensions are OK: check trust */
if (param->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);
/*
* Check revocation status: we do this after copying parameters because
* they may be needed for CRL signature verification.
*/
ok = ctx->check_revocation(ctx);
if (!ok)
goto end;
/* At this point, we have a chain and need to verify it */
if (ctx->verify != NULL)
ok = ctx->verify(ctx);
else
ok = internal_verify(ctx);
if (!ok)
goto end;
#ifndef OPENSSL_NO_RFC3779
/* RFC 3779 path validation, now that CRL check has been done */
ok = v3_asid_validate_path(ctx);
if (!ok)
goto end;
ok = v3_addr_validate_path(ctx);
if (!ok)
goto end;
#endif
/* If we get this far evaluate policies */
if (!bad_chain && (ctx->param->flags & X509_V_FLAG_POLICY_CHECK))
ok = ctx->check_policy(ctx);
if (!ok)
goto end;
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;
/* If we haven't asked for issuer errors don't set ctx */
if (!(ctx->param->flags & X509_V_FLAG_CB_ISSUER_CHECK))
return 0;
ctx->error = ret;
ctx->current_cert = x;
ctx->current_issuer = issuer;
return ctx->verify_cb(0, ctx);
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_extensions(X509_STORE_CTX *ctx)
{
#ifdef OPENSSL_NO_CHAIN_VERIFY
return 1;
#else
int i, ok = 0, must_be_ca, plen = 0;
X509 *x;
int (*cb) (int xok, X509_STORE_CTX *xctx);
int proxy_path_length = 0;
int allow_proxy_certs =
! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
cb = ctx->verify_cb;
/*-
* must_be_ca can have 1 of 3 values:
* -1: we accept both CA and non-CA certificates, to allow direct
* use of self-signed certificates (which are marked as CA).
* 0: we only accept non-CA certificates. This is currently not
* used, but the possibility is present for future extensions.
* 1: we only accept CA certificates. This is currently used for
* all certificates in the chain except the leaf certificate.
*/
must_be_ca = -1;
/*
* A hack to keep people who don't want to modify their software happy
*/
if (getenv("OPENSSL_ALLOW_PROXY_CERTS"))
allow_proxy_certs = 1;
/* Check all untrusted certificates */
for (i = 0; i < ctx->last_untrusted; i++) {
int ret;
x = sk_X509_value(ctx->chain, i);
if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
&& (x->ex_flags & EXFLAG_CRITICAL)) {
ctx->error = X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION;
ctx->error_depth = i;
ctx->current_cert = x;
ok = cb(0, ctx);
if (!ok)
goto end;
}
if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
ctx->error = X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED;
ctx->error_depth = i;
ctx->current_cert = x;
ok = cb(0, ctx);
if (!ok)
goto end;
}
ret = X509_check_ca(x);
switch (must_be_ca) {
case -1:
if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
&& (ret != 1) && (ret != 0)) {
ret = 0;
ctx->error = X509_V_ERR_INVALID_CA;
} else
ret = 1;
break;
case 0:
if (ret != 0) {
ret = 0;
ctx->error = X509_V_ERR_INVALID_NON_CA;
} else
ret = 1;
break;
default:
if ((ret == 0)
|| ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
&& (ret != 1))) {
ret = 0;
ctx->error = X509_V_ERR_INVALID_CA;
} else
ret = 1;
break;
}
if (ret == 0) {
ctx->error_depth = i;
ctx->current_cert = x;
ok = cb(0, ctx);
if (!ok)
goto end;
}
if (ctx->param->purpose > 0) {
ret = X509_check_purpose(x, ctx->param->purpose, must_be_ca > 0);
if ((ret == 0)
|| ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
&& (ret != 1))) {
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 not self issued */
if ((i > 1) && !(x->ex_flags & EXFLAG_SI)
&& (x->ex_pathlen != -1)
&& (plen > (x->ex_pathlen + proxy_path_length + 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;
}
/* Increment path length if not self issued */
if (!(x->ex_flags & EXFLAG_SI))
plen++;
/*
* If this certificate is a proxy certificate, the next certificate
* must be another proxy certificate or a EE certificate. If not,
* the next certificate must be a CA certificate.
*/
if (x->ex_flags & EXFLAG_PROXY) {
if (x->ex_pcpathlen != -1 && i > x->ex_pcpathlen) {
ctx->error = X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED;
ctx->error_depth = i;
ctx->current_cert = x;
ok = cb(0, ctx);
if (!ok)
goto end;
}
proxy_path_length++;
must_be_ca = 0;
} else
must_be_ca = 1;
}
ok = 1;
end:
return ok;
#endif
}
static int check_trust(X509_STORE_CTX *ctx)
{
#ifdef OPENSSL_NO_CHAIN_VERIFY
return 1;
#else
int i, ok;
X509 *x;
int (*cb) (int xok, X509_STORE_CTX *xctx);
cb = ctx->verify_cb;
/* 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->param->trust, 0);
if (ok == X509_TRUST_TRUSTED)
return 1;
ctx->error_depth = i;
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 check_revocation(X509_STORE_CTX *ctx)
{
int i, last, ok;
if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
return 1;
if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
last = sk_X509_num(ctx->chain) - 1;
else
last = 0;
for (i = 0; i <= last; i++) {
ctx->error_depth = i;
ok = check_cert(ctx);
if (!ok)
return ok;
}
return 1;
}
static int check_cert(X509_STORE_CTX *ctx)
{
X509_CRL *crl = NULL;
X509 *x;
int ok, cnum;
cnum = ctx->error_depth;
x = sk_X509_value(ctx->chain, cnum);
ctx->current_cert = x;
/* Try to retrieve relevant CRL */
ok = ctx->get_crl(ctx, &crl, x);
/*
* If error looking up CRL, nothing we can do except notify callback
*/
if (!ok) {
ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL;
ok = ctx->verify_cb(0, ctx);
goto err;
}
ctx->current_crl = crl;
ok = ctx->check_crl(ctx, crl);
if (!ok)
goto err;
ok = ctx->cert_crl(ctx, crl, x);
err:
ctx->current_crl = NULL;
X509_CRL_free(crl);
return ok;
}
/* Check CRL times against values in X509_STORE_CTX */
static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
{
time_t *ptime;
int i;
ctx->current_crl = crl;
if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
ptime = &ctx->param->check_time;
else
ptime = NULL;
i = X509_cmp_time(X509_CRL_get_lastUpdate(crl), ptime);
if (i == 0) {
ctx->error = X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD;
if (!notify || !ctx->verify_cb(0, ctx))
return 0;
}
if (i > 0) {
ctx->error = X509_V_ERR_CRL_NOT_YET_VALID;
if (!notify || !ctx->verify_cb(0, ctx))
return 0;
}
if (X509_CRL_get_nextUpdate(crl)) {
i = X509_cmp_time(X509_CRL_get_nextUpdate(crl), ptime);
if (i == 0) {
ctx->error = X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD;
if (!notify || !ctx->verify_cb(0, ctx))
return 0;
}
if (i < 0) {
ctx->error = X509_V_ERR_CRL_HAS_EXPIRED;
if (!notify || !ctx->verify_cb(0, ctx))
return 0;
}
}
ctx->current_crl = NULL;
return 1;
}
/*
* Lookup CRLs from the supplied list. Look for matching isser name and
* validity. If we can't find a valid CRL return the last one with matching
* name. This gives more meaningful error codes. Otherwise we'd get a CRL not
* found error if a CRL existed with matching name but was invalid.
*/
static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl,
X509_NAME *nm, STACK_OF(X509_CRL) *crls)
{
int i;
X509_CRL *crl, *best_crl = NULL;
for (i = 0; i < sk_X509_CRL_num(crls); i++) {
crl = sk_X509_CRL_value(crls, i);
if (X509_NAME_cmp(nm, X509_CRL_get_issuer(crl)))
continue;
if (check_crl_time(ctx, crl, 0)) {
*pcrl = crl;
CRYPTO_add(&crl->references, 1, CRYPTO_LOCK_X509);
return 1;
}
best_crl = crl;
}
if (best_crl) {
*pcrl = best_crl;
CRYPTO_add(&best_crl->references, 1, CRYPTO_LOCK_X509);
}
return 0;
}
/*
* Retrieve CRL corresponding to certificate: currently just a subject
* lookup: maybe use AKID later...
*/
static int get_crl(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509 *x)
{
int ok;
X509_CRL *crl = NULL;
X509_OBJECT xobj;
X509_NAME *nm;
nm = X509_get_issuer_name(x);
ok = get_crl_sk(ctx, &crl, nm, ctx->crls);
if (ok) {
*pcrl = crl;
return 1;
}
ok = X509_STORE_get_by_subject(ctx, X509_LU_CRL, nm, &xobj);
if (!ok) {
/* If we got a near match from get_crl_sk use that */
if (crl) {
*pcrl = crl;
return 1;
}
return 0;
}
*pcrl = xobj.data.crl;
if (crl)
X509_CRL_free(crl);
return 1;
}
/* Check CRL validity */
static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
{
X509 *issuer = NULL;
EVP_PKEY *ikey = NULL;
int ok = 0, chnum, cnum;
cnum = ctx->error_depth;
chnum = sk_X509_num(ctx->chain) - 1;
/*
* Find CRL issuer: if not last certificate then issuer is next
* certificate in chain.
*/
if (cnum < chnum)
issuer = sk_X509_value(ctx->chain, cnum + 1);
else {
issuer = sk_X509_value(ctx->chain, chnum);
/* If not self signed, can't check signature */
if (!ctx->check_issued(ctx, issuer, issuer)) {
ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER;
ok = ctx->verify_cb(0, ctx);
if (!ok)
goto err;
}
}
if (issuer) {
/* Check for cRLSign bit if keyUsage present */
if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
!(issuer->ex_kusage & KU_CRL_SIGN)) {
ctx->error = X509_V_ERR_KEYUSAGE_NO_CRL_SIGN;
ok = ctx->verify_cb(0, ctx);
if (!ok)
goto err;
}
/* Attempt to get issuer certificate public key */
ikey = X509_get_pubkey(issuer);
if (!ikey) {
ctx->error = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
ok = ctx->verify_cb(0, ctx);
if (!ok)
goto err;
} else {
/* Verify CRL signature */
if (X509_CRL_verify(crl, ikey) <= 0) {
ctx->error = X509_V_ERR_CRL_SIGNATURE_FAILURE;
ok = ctx->verify_cb(0, ctx);
if (!ok)
goto err;
}
}
}
ok = check_crl_time(ctx, crl, 1);
if (!ok)
goto err;
ok = 1;
err:
EVP_PKEY_free(ikey);
return ok;
}
/* Check certificate against CRL */
static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
{
int idx, ok;
X509_REVOKED rtmp;
STACK_OF(X509_EXTENSION) *exts;
X509_EXTENSION *ext;
/* Look for serial number of certificate in CRL */
rtmp.serialNumber = X509_get_serialNumber(x);
/*
* Sort revoked into serial number order if not already sorted. Do this
* under a lock to avoid race condition.
*/
if (!sk_X509_REVOKED_is_sorted(crl->crl->revoked)) {
CRYPTO_w_lock(CRYPTO_LOCK_X509_CRL);
sk_X509_REVOKED_sort(crl->crl->revoked);
CRYPTO_w_unlock(CRYPTO_LOCK_X509_CRL);
}
idx = sk_X509_REVOKED_find(crl->crl->revoked, &rtmp);
/*
* If found assume revoked: want something cleverer than this to handle
* entry extensions in V2 CRLs.
*/
if (idx >= 0) {
ctx->error = X509_V_ERR_CERT_REVOKED;
ok = ctx->verify_cb(0, ctx);
if (!ok)
return 0;
}
if (ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
return 1;
/*
* See if we have any critical CRL extensions: since we currently don't
* handle any CRL extensions the CRL must be rejected. This code
* accesses the X509_CRL structure directly: applications shouldn't do
* this.
*/
exts = crl->crl->extensions;
for (idx = 0; idx < sk_X509_EXTENSION_num(exts); idx++) {
ext = sk_X509_EXTENSION_value(exts, idx);
if (ext->critical > 0) {
ctx->error = X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION;
ok = ctx->verify_cb(0, ctx);
if (!ok)
return 0;
break;
}
}
return 1;
}
static int check_policy(X509_STORE_CTX *ctx)
{
int ret;
ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
ctx->param->policies, ctx->param->flags);
if (ret == 0) {
X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
return 0;
}
/* Invalid or inconsistent extensions */
if (ret == -1) {
/*
* Locate certificates with bad extensions and notify callback.
*/
X509 *x;
int i;
for (i = 1; i < sk_X509_num(ctx->chain); i++) {
x = sk_X509_value(ctx->chain, i);
if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
continue;
ctx->current_cert = x;
ctx->error = X509_V_ERR_INVALID_POLICY_EXTENSION;
ret = ctx->verify_cb(0, ctx);
}
return 1;
}
if (ret == -2) {
ctx->current_cert = NULL;
ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
return ctx->verify_cb(0, ctx);
}
if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
ctx->current_cert = NULL;
ctx->error = X509_V_OK;
if (!ctx->verify_cb(2, ctx))
return 0;
}
return 1;
}
static int check_cert_time(X509_STORE_CTX *ctx, X509 *x)
{
time_t *ptime;
int i;
if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
ptime = &ctx->param->check_time;
else
ptime = NULL;
i = X509_cmp_time(X509_get_notBefore(x), ptime);
if (i == 0) {
ctx->error = X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD;
ctx->current_cert = x;
if (!ctx->verify_cb(0, ctx))
return 0;
}
if (i > 0) {
ctx->error = X509_V_ERR_CERT_NOT_YET_VALID;
ctx->current_cert = x;
if (!ctx->verify_cb(0, ctx))
return 0;
}
i = X509_cmp_time(X509_get_notAfter(x), ptime);
if (i == 0) {
ctx->error = X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD;
ctx->current_cert = x;
if (!ctx->verify_cb(0, ctx))
return 0;
}
if (i < 0) {
ctx->error = X509_V_ERR_CERT_HAS_EXPIRED;
ctx->current_cert = x;
if (!ctx->verify_cb(0, ctx))
return 0;
}
return 1;
}
static int internal_verify(X509_STORE_CTX *ctx)
{
int ok = 0, n;
X509 *xs, *xi;
EVP_PKEY *pkey = NULL;
int (*cb) (int xok, X509_STORE_CTX *xctx);
cb = ctx->verify_cb;
n = sk_X509_num(ctx->chain);
ctx->error_depth = n - 1;
n--;
xi = sk_X509_value(ctx->chain, n);
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;
/*
* Skip signature check for self signed certificates unless
* explicitly asked for. It doesn't add any security and just wastes
* time.
*/
if (!xs->valid
&& (xs != xi
|| (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE))) {
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;
} else 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;
}
xs->valid = 1;
ok = check_cert_time(ctx, xs);
if (!ok)
goto end;
/* The last error (if any) is still in the error value */
ctx->current_issuer = xi;
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;
long offset;
char buff1[24], buff2[24], *p;
int i, j, remaining;
p = buff1;
remaining = ctm->length;
str = (char *)ctm->data;
/*
* Note that the following (historical) code allows much more slack in the
* time format than RFC5280. In RFC5280, the representation is fixed:
* UTCTime: YYMMDDHHMMSSZ
* GeneralizedTime: YYYYMMDDHHMMSSZ
*/
if (ctm->type == V_ASN1_UTCTIME) {
/* YYMMDDHHMM[SS]Z or YYMMDDHHMM[SS](+-)hhmm */
int min_length = sizeof("YYMMDDHHMMZ") - 1;
int max_length = sizeof("YYMMDDHHMMSS+hhmm") - 1;
if (remaining < min_length || remaining > max_length)
return 0;
memcpy(p, str, 10);
p += 10;
str += 10;
remaining -= 10;
} else {
/* YYYYMMDDHHMM[SS[.fff]]Z or YYYYMMDDHHMM[SS[.f[f[f]]]](+-)hhmm */
int min_length = sizeof("YYYYMMDDHHMMZ") - 1;
int max_length = sizeof("YYYYMMDDHHMMSS.fff+hhmm") - 1;
if (remaining < min_length || remaining > max_length)
return 0;
memcpy(p, str, 12);
p += 12;
str += 12;
remaining -= 12;
}
if ((*str == 'Z') || (*str == '-') || (*str == '+')) {
*(p++) = '0';
*(p++) = '0';
} else {
/* SS (seconds) */
if (remaining < 2)
return 0;
*(p++) = *(str++);
*(p++) = *(str++);
remaining -= 2;
/*
* Skip any (up to three) fractional seconds...
* TODO(emilia): in RFC5280, fractional seconds are forbidden.
* Can we just kill them altogether?
*/
if (remaining && *str == '.') {
str++;
remaining--;
for (i = 0; i < 3 && remaining; i++, str++, remaining--) {
if (*str < '0' || *str > '9')
break;
}
}
}
*(p++) = 'Z';
*(p++) = '\0';
/* We now need either a terminating 'Z' or an offset. */
if (!remaining)
return 0;
if (*str == 'Z') {
if (remaining != 1)
return 0;
offset = 0;
} else {
/* (+-)HHMM */
if ((*str != '+') && (*str != '-'))
return 0;
/* Historical behaviour: the (+-)hhmm offset is forbidden in RFC5280. */
if (remaining != 5)
return 0;
if (str[1] < '0' || str[1] > '9' || str[2] < '0' || str[2] > '9' ||
str[3] < '0' || str[3] > '9' || str[4] < '0' || str[4] > '9')
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;
if (X509_time_adj(&atm, offset * 60, cmp_time) == NULL)
return 0;
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;
int type = -1;
if (in_tm)
t = *in_tm;
else
time(&t);
t += adj;
if (s)
type = s->type;
if (type == V_ASN1_UTCTIME)
return ASN1_UTCTIME_set(s, t);
if (type == V_ASN1_GENERALIZEDTIME)
return ASN1_GENERALIZEDTIME_set(s, t);
return ASN1_TIME_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)
{
/*
* This function is (usually) called only once, by
* SSL_get_ex_data_X509_STORE_CTX_idx (ssl/ssl_cert.c).
*/
return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_X509_STORE_CTX, 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;
}
void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
{
ctx->crls = 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->param->purpose)
ctx->param->purpose = purpose;
if (trust && !ctx->param->trust)
ctx->param->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) {
X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
return NULL;
}
memset(ctx, 0, sizeof(X509_STORE_CTX));
return ctx;
}
void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
{
if (!ctx)
return;
X509_STORE_CTX_cleanup(ctx);
OPENSSL_free(ctx);
}
int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
STACK_OF(X509) *chain)
{
int ret = 1;
ctx->ctx = store;
ctx->current_method = 0;
ctx->cert = x509;
ctx->untrusted = chain;
ctx->crls = NULL;
ctx->last_untrusted = 0;
ctx->other_ctx = NULL;
ctx->valid = 0;
ctx->chain = NULL;
ctx->error = 0;
ctx->explicit_policy = 0;
ctx->error_depth = 0;
ctx->current_cert = NULL;
ctx->current_issuer = NULL;
ctx->tree = NULL;
ctx->param = X509_VERIFY_PARAM_new();
if (!ctx->param) {
X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
return 0;
}
/*
* Inherit callbacks and flags from X509_STORE if not set use defaults.
*/
if (store)
ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
else
ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
if (store) {
ctx->verify_cb = store->verify_cb;
ctx->cleanup = store->cleanup;
} else
ctx->cleanup = 0;
if (ret)
ret = X509_VERIFY_PARAM_inherit(ctx->param,
X509_VERIFY_PARAM_lookup("default"));
if (ret == 0) {
X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
return 0;
}
if (store && store->check_issued)
ctx->check_issued = store->check_issued;
else
ctx->check_issued = check_issued;
if (store && store->get_issuer)
ctx->get_issuer = store->get_issuer;
else
ctx->get_issuer = X509_STORE_CTX_get1_issuer;
if (store && store->verify_cb)
ctx->verify_cb = store->verify_cb;
else
ctx->verify_cb = null_callback;
if (store && store->verify)
ctx->verify = store->verify;
else
ctx->verify = internal_verify;
if (store && store->check_revocation)
ctx->check_revocation = store->check_revocation;
else
ctx->check_revocation = check_revocation;
if (store && store->get_crl)
ctx->get_crl = store->get_crl;
else
ctx->get_crl = get_crl;
if (store && store->check_crl)
ctx->check_crl = store->check_crl;
else
ctx->check_crl = check_crl;
if (store && store->cert_crl)
ctx->cert_crl = store->cert_crl;
else
ctx->cert_crl = cert_crl;
ctx->check_policy = check_policy;
/*
* This memset() can't make any sense anyway, so it's removed. As
* X509_STORE_CTX_cleanup does a proper "free" on the ex_data, we put a
* corresponding "new" here and remove this bogus initialisation.
*/
/* memset(&(ctx->ex_data),0,sizeof(CRYPTO_EX_DATA)); */
if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
&(ctx->ex_data))) {
OPENSSL_free(ctx);
X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
return 0;
}
return 1;
}
/*
* 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->param != NULL) {
X509_VERIFY_PARAM_free(ctx->param);
ctx->param = NULL;
}
if (ctx->tree != NULL) {
X509_policy_tree_free(ctx->tree);
ctx->tree = NULL;
}
if (ctx->chain != NULL) {
sk_X509_pop_free(ctx->chain, X509_free);
ctx->chain = NULL;
}
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
memset(&ctx->ex_data, 0, sizeof(CRYPTO_EX_DATA));
}
void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
{
X509_VERIFY_PARAM_set_depth(ctx->param, depth);
}
void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
{
X509_VERIFY_PARAM_set_flags(ctx->param, flags);
}
void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
time_t t)
{
X509_VERIFY_PARAM_set_time(ctx->param, t);
}
void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
int (*verify_cb) (int, X509_STORE_CTX *))
{
ctx->verify_cb = verify_cb;
}
X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
{
return ctx->tree;
}
int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
{
return ctx->explicit_policy;
}
int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
{
const X509_VERIFY_PARAM *param;
param = X509_VERIFY_PARAM_lookup(name);
if (!param)
return 0;
return X509_VERIFY_PARAM_inherit(ctx->param, param);
}
X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
{
return ctx->param;
}
void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
{
if (ctx->param)
X509_VERIFY_PARAM_free(ctx->param);
ctx->param = param;
}
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)
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