#include <stdio.h>
#include <time.h>
#include <errno.h>
+#include <limits.h>
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
#include <openssl/crypto.h>
#include <openssl/lhash.h>
#include <openssl/buffer.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include <openssl/objects.h>
+#include <internal/dane.h>
+#include <internal/x509_int.h>
#include "x509_lcl.h"
/* CRL score values */
#define CRL_SCORE_TIME_DELTA 0x002
+static int build_chain(X509_STORE_CTX *ctx);
+static int verify_chain(X509_STORE_CTX *ctx);
+static int dane_verify(X509_STORE_CTX *ctx);
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_name_constraints(X509_STORE_CTX *ctx);
static int check_id(X509_STORE_CTX *ctx);
-static int check_trust(X509_STORE_CTX *ctx);
+static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
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 get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
+static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
unsigned int *preasons, X509_CRL *crl, X509 *x);
STACK_OF(X509) *crl_path);
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 1 is a certificate is self signed */
static int cert_self_signed(X509 *x)
{
+ /*
+ * FIXME: x509v3_cache_extensions() needs to detect more failures and not
+ * set EXFLAG_SET when that happens. Especially, if the failures are
+ * parse errors, rather than memory pressure!
+ */
X509_check_purpose(x, -1, 0);
if (x->ex_flags & EXFLAG_SS)
return 1;
break;
}
if (i < sk_X509_num(certs))
- CRYPTO_add(&xtmp->references, 1, CRYPTO_LOCK_X509);
+ X509_up_ref(xtmp);
else
xtmp = NULL;
sk_X509_pop_free(certs, X509_free);
return xtmp;
}
-int X509_verify_cert(X509_STORE_CTX *ctx)
+static int verify_chain(X509_STORE_CTX *ctx)
{
- X509 *x, *xtmp, *xtmp2, *chain_ss = NULL;
- int bad_chain = 0;
- X509_VERIFY_PARAM *param = ctx->param;
- int depth, i, ok = 0;
- int num, j, retry;
- 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;
+ int (*cb) (int xok, X509_STORE_CTX *xctx) = ctx->verify_cb;
+ int err;
+ int ok;
/*
- * first we make sure the chain we are going to build is present and that
- * the first entry is in place
+ * Before either returning with an error, or continuing with CRL checks,
+ * instantiate chain public key parameters.
*/
- 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;
- }
+ if ((ok = build_chain(ctx)) == 0 ||
+ (ok = check_chain_extensions(ctx)) == 0 ||
+ (ok = check_name_constraints(ctx)) == 0 ||
+ (ok = check_id(ctx)) == 0 || 1)
+ X509_get_pubkey_parameters(NULL, ctx->chain);
+ if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
+ return ok;
- /* 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;
+ err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
+ ctx->param->flags);
+ if (err != X509_V_OK) {
+ ctx->error = err;
+ ctx->current_cert = sk_X509_value(ctx->chain, ctx->error_depth);
+ if ((ok = cb(0, ctx)) == 0)
+ return ok;
}
- 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 (cert_self_signed(x))
- break;
- /*
- * If asked see if we can find issuer in trusted store first
- */
- if (ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST) {
- ok = ctx->get_issuer(&xtmp, ctx, x);
- if (ok < 0)
- return ok;
- /*
- * If successful for now free up cert so it will be picked up
- * again later.
- */
- if (ok > 0) {
- X509_free(xtmp);
- 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;
- }
+ /* Verify chain signatures and expiration times */
+ ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
+ if (!ok)
+ return ok;
- /* Remember how many untrusted certs we have */
- j = num;
- /*
- * 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.
- */
+#ifndef OPENSSL_NO_RFC3779
+ /* RFC 3779 path validation, now that CRL check has been done */
+ if ((ok = v3_asid_validate_path(ctx)) == 0)
+ return ok;
+ if ((ok = v3_addr_validate_path(ctx)) == 0)
+ return ok;
+#endif
- do {
- /*
- * 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 (cert_self_signed(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--;
- j--;
- 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 (cert_self_signed(x))
- break;
- ok = ctx->get_issuer(&xtmp, ctx, x);
+ /* If we get this far evaluate policies */
+ if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
+ ok = ctx->check_policy(ctx);
+ return ok;
+}
- 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++;
- }
+int X509_verify_cert(X509_STORE_CTX *ctx)
+{
+ struct dane_st *dane = (struct dane_st *)ctx->dane;
- /* we now have our chain, lets check it... */
- i = check_trust(ctx);
+ if (ctx->cert == NULL) {
+ X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
+ return -1;
+ }
- /* If explicitly rejected error */
- if (i == X509_TRUST_REJECTED)
- goto end;
+ if (ctx->chain != NULL) {
/*
- * If it's not explicitly trusted then check if there is an alternative
- * chain that could be used. We only do this if we haven't already
- * checked via TRUSTED_FIRST and the user hasn't switched off alternate
- * chain checking
+ * This X509_STORE_CTX has already been used to verify a cert. We
+ * cannot do another one.
*/
- retry = 0;
- if (i != X509_TRUST_TRUSTED
- && !(ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
- && !(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS)) {
- while (j-- > 1) {
- STACK_OF(X509) *chtmp = ctx->chain;
- xtmp2 = sk_X509_value(ctx->chain, j - 1);
- /*
- * Temporarily set chain to NULL so we don't discount
- * duplicates: the same certificate could be an untrusted
- * CA found in the trusted store.
- */
- ctx->chain = NULL;
- ok = ctx->get_issuer(&xtmp, ctx, xtmp2);
- ctx->chain = chtmp;
- if (ok < 0)
- goto end;
- /* Check if we found an alternate chain */
- if (ok > 0) {
- /*
- * Free up the found cert we'll add it again later
- */
- X509_free(xtmp);
-
- /*
- * Dump all the certs above this point - we've found an
- * alternate chain
- */
- while (num > j) {
- xtmp = sk_X509_pop(ctx->chain);
- X509_free(xtmp);
- num--;
- ctx->last_untrusted--;
- }
- retry = 1;
- break;
- }
- }
- }
- } while (retry);
+ X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
+ return -1;
+ }
/*
- * If not explicitly trusted then indicate error unless it's a single
- * self signed certificate in which case we've indicated an error already
- * and set bad_chain == 1
+ * first we make sure the chain we are going to build is present and that
+ * the first entry is in place
*/
- if (i != X509_TRUST_TRUSTED && !bad_chain) {
- 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;
+ 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);
+ return -1;
}
-
- /* We have the chain complete: now we need to check its purpose */
- ok = check_chain_extensions(ctx);
-
- if (!ok)
- goto end;
-
- /* Check name constraints */
-
- ok = check_name_constraints(ctx);
-
- if (!ok)
- goto end;
-
- ok = check_id(ctx);
-
- if (!ok)
- goto end;
-
- /* We may as well copy down any DSA parameters that are required */
- X509_get_pubkey_parameters(NULL, ctx->chain);
+ X509_up_ref(ctx->cert);
+ ctx->num_untrusted = 1;
/*
- * Check revocation status: we do this after copying parameters because
- * they may be needed for CRL signature verification.
+ * If dane->trecs is an empty stack, we'll fail, since the user enabled
+ * DANE. If none of the TLSA records were usable, and it makes sense to
+ * keep going with an unauthenticated handshake, they can handle that in
+ * the verify callback, or not set SSL_VERIFY_PEER.
*/
-
- ok = ctx->check_revocation(ctx);
- if (!ok)
- goto end;
-
- i = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
- ctx->param->flags);
- if (i != X509_V_OK) {
- ctx->error = i;
- ctx->current_cert = sk_X509_value(ctx->chain, ctx->error_depth);
- ok = cb(0, 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;
-
- /* 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;
-
- /* 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;
+ if (DANETLS_ENABLED(dane))
+ return dane_verify(ctx);
+ return verify_chain(ctx);
}
/*
{
*issuer = find_issuer(ctx, ctx->other_ctx, x);
if (*issuer) {
- CRYPTO_add(&(*issuer)->references, 1, CRYPTO_LOCK_X509);
+ X509_up_ref(*issuer);
return 1;
} else
return 0;
}
+static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
+{
+ STACK_OF(X509) *sk = NULL;
+ X509 *x;
+ int i;
+ for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
+ x = sk_X509_value(ctx->other_ctx, i);
+ if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
+ if (sk == NULL)
+ sk = sk_X509_new_null();
+ if (sk == NULL || sk_X509_push(sk, x) == 0) {
+ sk_X509_pop_free(sk, X509_free);
+ return NULL;
+ }
+ X509_up_ref(x);
+ }
+ }
+ return sk;
+}
+
/*
* Check a certificate chains extensions for consistency with the supplied
* purpose
}
/* Check all untrusted certificates */
- for (i = 0; i < ctx->last_untrusted; i++) {
+ for (i = 0; i == 0 || i < ctx->num_untrusted; i++) {
int ret;
x = sk_X509_value(ctx->chain, i);
if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
return ctx->verify_cb(0, ctx);
}
-static int check_hosts(X509 *x, X509_VERIFY_PARAM_ID *id)
+static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
{
int i;
- int n = sk_OPENSSL_STRING_num(id->hosts);
+ int n = sk_OPENSSL_STRING_num(vpm->hosts);
char *name;
+ if (vpm->peername != NULL) {
+ OPENSSL_free(vpm->peername);
+ vpm->peername = NULL;
+ }
for (i = 0; i < n; ++i) {
- name = sk_OPENSSL_STRING_value(id->hosts, i);
- if (X509_check_host(x, name, 0, id->hostflags, &id->peername) > 0)
+ name = sk_OPENSSL_STRING_value(vpm->hosts, i);
+ if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
return 1;
}
return n == 0;
static int check_id(X509_STORE_CTX *ctx)
{
X509_VERIFY_PARAM *vpm = ctx->param;
- X509_VERIFY_PARAM_ID *id = vpm->id;
X509 *x = ctx->cert;
- if (id->hosts && check_hosts(x, id) <= 0) {
+ if (vpm->hosts && check_hosts(x, vpm) <= 0) {
if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
return 0;
}
- if (id->email && X509_check_email(x, id->email, id->emaillen, 0) <= 0) {
+ if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
return 0;
}
- if (id->ip && X509_check_ip(x, id->ip, id->iplen, 0) <= 0) {
+ if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
return 0;
}
return 1;
}
-static int check_trust(X509_STORE_CTX *ctx)
+static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
{
- int i, ok;
+ int i, ok = 0;
X509 *x = NULL;
- int (*cb) (int xok, X509_STORE_CTX *xctx);
- cb = ctx->verify_cb;
- /* Check all trusted certificates in chain */
- for (i = ctx->last_untrusted; i < sk_X509_num(ctx->chain); i++) {
+ X509 *mx;
+ int (*cb) (int xok, X509_STORE_CTX *xctx) = ctx->verify_cb;
+ struct dane_st *dane = (struct dane_st *)ctx->dane;
+ int num = sk_X509_num(ctx->chain);
+ int trust;
+
+ /*
+ * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
+ * match, we're done, otherwise we'll merely record the match depth.
+ */
+ if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
+ switch (trust = check_dane_issuer(ctx, num_untrusted)) {
+ case X509_TRUST_TRUSTED:
+ case X509_TRUST_REJECTED:
+ return trust;
+ }
+ }
+
+ /*
+ * Check trusted certificates in chain at depth num_untrusted and up.
+ * Note, that depths 0..num_untrusted-1 may also contain trusted
+ * certificates, but the caller is expected to have already checked those,
+ * and wants to incrementally check just any added since.
+ */
+ for (i = num_untrusted; i < num; i++) {
x = sk_X509_value(ctx->chain, i);
- ok = X509_check_trust(x, ctx->param->trust, 0);
+ trust = X509_check_trust(x, ctx->param->trust, 0);
/* If explicitly trusted return trusted */
- if (ok == X509_TRUST_TRUSTED)
- return X509_TRUST_TRUSTED;
- /*
- * If explicitly rejected notify callback and reject if not
- * overridden.
- */
- if (ok == X509_TRUST_REJECTED) {
- ctx->error_depth = i;
- ctx->current_cert = x;
- ctx->error = X509_V_ERR_CERT_REJECTED;
- ok = cb(0, ctx);
- if (!ok)
- return X509_TRUST_REJECTED;
- }
+ if (trust == X509_TRUST_TRUSTED)
+ goto trusted;
+ if (trust == X509_TRUST_REJECTED)
+ goto rejected;
}
+
/*
- * If we accept partial chains and have at least one trusted certificate
- * return success.
+ * If we are looking at a trusted certificate, and accept partial chains,
+ * the chain is PKIX trusted.
*/
- if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
- X509 *mx;
- if (ctx->last_untrusted < sk_X509_num(ctx->chain))
- return X509_TRUST_TRUSTED;
- x = sk_X509_value(ctx->chain, 0);
+ if (num_untrusted < num) {
+ if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
+ goto trusted;
+ return X509_TRUST_UNTRUSTED;
+ }
+
+ if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
+ /*
+ * Last-resort call with no new trusted certificates, check the leaf
+ * for a direct trust store match.
+ */
+ i = 0;
+ x = sk_X509_value(ctx->chain, i);
mx = lookup_cert_match(ctx, x);
- if (mx) {
- (void)sk_X509_set(ctx->chain, 0, mx);
- X509_free(x);
- ctx->last_untrusted = 0;
- return X509_TRUST_TRUSTED;
+ if (!mx)
+ return X509_TRUST_UNTRUSTED;
+
+ /*
+ * Check explicit auxiliary trust/reject settings. If none are set,
+ * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
+ */
+ trust = X509_check_trust(mx, ctx->param->trust, 0);
+ if (trust == X509_TRUST_REJECTED) {
+ X509_free(mx);
+ goto rejected;
}
+
+ /* Replace leaf with trusted match */
+ (void) sk_X509_set(ctx->chain, 0, mx);
+ X509_free(x);
+ ctx->num_untrusted = 0;
+ goto trusted;
}
/*
* standard (no issuer cert) etc errors to be indicated.
*/
return X509_TRUST_UNTRUSTED;
+
+ rejected:
+ ctx->error_depth = i;
+ ctx->current_cert = x;
+ ctx->error = X509_V_ERR_CERT_REJECTED;
+ ok = cb(0, ctx);
+ if (!ok)
+ return X509_TRUST_REJECTED;
+ return X509_TRUST_UNTRUSTED;
+
+ trusted:
+ if (!DANETLS_ENABLED(dane))
+ return X509_TRUST_TRUSTED;
+ if (dane->pdpth < 0)
+ dane->pdpth = num_untrusted;
+ /* With DANE, PKIX alone is not trusted until we have both */
+ if (dane->mdpth >= 0)
+ return X509_TRUST_TRUSTED;
+ return X509_TRUST_UNTRUSTED;
}
static int check_revocation(X509_STORE_CTX *ctx)
{
- int i, last, ok;
+ int i = 0, last = 0, ok = 0;
if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
return 1;
if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
static int check_cert(X509_STORE_CTX *ctx)
{
X509_CRL *crl = NULL, *dcrl = NULL;
- X509 *x;
- int ok, cnum;
- unsigned int last_reasons;
+ X509 *x = NULL;
+ int ok = 0, cnum = 0;
+ unsigned int last_reasons = 0;
cnum = ctx->error_depth;
x = sk_X509_value(ctx->chain, cnum);
ctx->current_cert = x;
ctx->current_crl = crl;
if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
ptime = &ctx->param->check_time;
+ else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
+ return 1;
else
ptime = NULL;
}
if (best_crl) {
- if (*pcrl)
- X509_CRL_free(*pcrl);
+ X509_CRL_free(*pcrl);
*pcrl = best_crl;
*pissuer = best_crl_issuer;
*pscore = best_score;
*preasons = best_reasons;
- CRYPTO_add(&best_crl->references, 1, CRYPTO_LOCK_X509_CRL);
- if (*pdcrl) {
- X509_CRL_free(*pdcrl);
- *pdcrl = NULL;
- }
+ X509_CRL_up_ref(best_crl);
+ X509_CRL_free(*pdcrl);
+ *pdcrl = NULL;
get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
}
if (check_delta_base(delta, base)) {
if (check_crl_time(ctx, delta, 0))
*pscore |= CRL_SCORE_TIME_DELTA;
- CRYPTO_add(&delta->references, 1, CRYPTO_LOCK_X509_CRL);
+ X509_CRL_up_ref(delta);
*dcrl = delta;
return;
}
}
/* Attempt to get issuer certificate public key */
- ikey = X509_get_pubkey(issuer);
+ ikey = X509_get0_pubkey(issuer);
if (!ikey) {
ctx->error = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
ok = 1;
err:
- EVP_PKEY_free(ikey);
return ok;
}
if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
ptime = &ctx->param->check_time;
+ else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
+ return 1;
else
ptime = NULL;
cb = ctx->verify_cb;
- n = sk_X509_num(ctx->chain);
- ctx->error_depth = n - 1;
- n--;
+ n = sk_X509_num(ctx->chain) - 1;
+ ctx->error_depth = n;
xi = sk_X509_value(ctx->chain, n);
+ /*
+ * With DANE-verified bare public key TA signatures, it remains only to
+ * check the timestamps of the top certificate. We report the issuer as
+ * NULL, since all we have is a bare key.
+ */
+ if (ctx->bare_ta_signed) {
+ xs = xi;
+ xi = NULL;
+ goto check_cert;
+ }
+
if (ctx->check_issued(ctx, xi, xi))
xs = xi;
else {
}
}
-/* ctx->error=0; not needed */
+ /*
+ * Do not clear ctx->error=0, it must be "sticky", only the user's callback
+ * is allowed to reset errors (at its own peril).
+ */
while (n >= 0) {
ctx->error_depth = n;
if (!xs->valid
&& (xs != xi
|| (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE))) {
- if ((pkey = X509_get_pubkey(xi)) == NULL) {
+ if ((pkey = X509_get0_pubkey(xi)) == NULL) {
ctx->error = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
ctx->current_cert = xi;
ok = (*cb) (0, ctx);
ctx->error = X509_V_ERR_CERT_SIGNATURE_FAILURE;
ctx->current_cert = xs;
ok = (*cb) (0, ctx);
- if (!ok) {
- EVP_PKEY_free(pkey);
+ if (!ok)
goto end;
- }
}
- EVP_PKEY_free(pkey);
- pkey = NULL;
}
xs->valid = 1;
ASN1_TIME atm;
long offset;
char buff1[24], buff2[24], *p;
- int i, j;
+ int i, j, remaining;
p = buff1;
- i = ctm->length;
+ 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) {
- if ((i < 11) || (i > 17))
+ /* 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 {
- if (i < 13)
+ /* 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++);
- /* Skip any fractional seconds... */
- if (*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++;
- while ((*str >= '0') && (*str <= '9'))
- str++;
+ remaining--;
+ for (i = 0; i < 3 && remaining; i++, str++, remaining--) {
+ if (*str < '0' || *str > '9')
+ break;
+ }
}
}
*(p++) = 'Z';
*(p++) = '\0';
- if (*str == 'Z')
+ /* 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 {
+ } 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 == '-')
return 1;
for (i = 0; i < sk_X509_num(chain); i++) {
- ktmp = X509_get_pubkey(sk_X509_value(chain, i));
+ ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
if (ktmp == NULL) {
X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
}
if (!EVP_PKEY_missing_parameters(ktmp))
break;
- EVP_PKEY_free(ktmp);
- ktmp = NULL;
}
if (ktmp == NULL) {
X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
/* first, populate the other certs */
for (j = i - 1; j >= 0; j--) {
- ktmp2 = X509_get_pubkey(sk_X509_value(chain, j));
+ ktmp2 = X509_get0_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;
}
}
/* Create new CRL */
crl = X509_CRL_new();
- if (!crl || !X509_CRL_set_version(crl, 1))
+ if (crl == NULL || !X509_CRL_set_version(crl, 1))
goto memerr;
/* Set issuer name */
if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
* Add only if not also in base. TODO: need something cleverer here
* for some more complex CRLs covering multiple CAs.
*/
- if (!X509_CRL_get0_by_serial(base, &rvtmp, rvn->serialNumber)) {
+ if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
rvtmp = X509_REVOKED_dup(rvn);
if (!rvtmp)
goto memerr;
memerr:
X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
- if (crl)
- X509_CRL_free(crl);
+ X509_CRL_free(crl);
return NULL;
}
-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);
X509_STORE_CTX *X509_STORE_CTX_new(void)
{
- X509_STORE_CTX *ctx;
- ctx = (X509_STORE_CTX *)OPENSSL_malloc(sizeof(X509_STORE_CTX));
- if (!ctx) {
+ X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
+
+ if (ctx == NULL) {
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);
}
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->num_untrusted = 0;
ctx->other_ctx = NULL;
ctx->valid = 0;
ctx->chain = NULL;
ctx->current_reasons = 0;
ctx->tree = NULL;
ctx->parent = 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;
+ ctx->dane = NULL;
+ ctx->bare_ta_signed = 0;
+ /* Zero ex_data to make sure we're cleanup-safe */
+ memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
if (store) {
ctx->verify_cb = store->verify_cb;
+ /* Seems to always be 0 in OpenSSL, else must be idempotent */
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_policy = check_policy;
+ ctx->param = X509_VERIFY_PARAM_new();
+ if (ctx->param == NULL) {
+ X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+
/*
- * 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.
+ * Inherit callbacks and flags from X509_STORE if not set use defaults.
*/
- /* 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);
+ 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 (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;
+ goto err;
}
- return 1;
+
+ if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
+ &ctx->ex_data))
+ return 1;
+ X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
+
+ err:
+ /*
+ * On error clean up allocated storage, if the store context was not
+ * allocated with X509_STORE_CTX_new() this is our last chance to do so.
+ */
+ X509_STORE_CTX_cleanup(ctx);
+ return 0;
}
/*
{
ctx->other_ctx = sk;
ctx->get_issuer = get_issuer_sk;
+ ctx->lookup_certs = lookup_certs_sk;
}
void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
{
- if (ctx->cleanup)
+ /*
+ * We need to be idempotent because, unfortunately, free() also calls
+ * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
+ * calls cleanup() for the same object twice! Thus we must zero the
+ * pointers below after they're freed!
+ */
+ /* Seems to always be 0 in OpenSSL, do this at most once. */
+ if (ctx->cleanup != NULL) {
ctx->cleanup(ctx);
+ ctx->cleanup = NULL;
+ }
if (ctx->param != NULL) {
if (ctx->parent == 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;
- }
+ X509_policy_tree_free(ctx->tree);
+ ctx->tree = 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));
+ memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
}
void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
return ctx->explicit_policy;
}
+int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
+{
+ return ctx->num_untrusted;
+}
+
int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
{
const X509_VERIFY_PARAM *param;
void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
{
- if (ctx->param)
- X509_VERIFY_PARAM_free(ctx->param);
+ X509_VERIFY_PARAM_free(ctx->param);
ctx->param = param;
}
+
+void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, struct dane_st *dane)
+{
+ ctx->dane = dane;
+}
+
+static unsigned char *dane_i2d(
+ X509 *cert,
+ uint8_t selector,
+ unsigned int *i2dlen)
+{
+ unsigned char *buf = NULL;
+ int len;
+
+ /*
+ * Extract ASN.1 DER form of certificate or public key.
+ */
+ switch (selector) {
+ case DANETLS_SELECTOR_CERT:
+ len = i2d_X509(cert, &buf);
+ break;
+ case DANETLS_SELECTOR_SPKI:
+ len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
+ break;
+ default:
+ X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
+ return NULL;
+ }
+
+ if (len < 0 || buf == NULL) {
+ X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+
+ *i2dlen = (unsigned int)len;
+ return buf;
+}
+
+#define DANETLS_NONE 256 /* impossible uint8_t */
+
+static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
+{
+ struct dane_st *dane = (struct dane_st *)ctx->dane;
+ unsigned usage = DANETLS_NONE;
+ unsigned selector = DANETLS_NONE;
+ unsigned ordinal = DANETLS_NONE;
+ unsigned mtype = DANETLS_NONE;
+ unsigned char *i2dbuf = NULL;
+ unsigned int i2dlen = 0;
+ unsigned char mdbuf[EVP_MAX_MD_SIZE];
+ unsigned char *cmpbuf = NULL;
+ unsigned int cmplen = 0;
+ int i;
+ int recnum;
+ int matched = 0;
+ danetls_record *t = NULL;
+ uint32_t mask;
+
+ mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
+
+ /*
+ * The trust store is not applicable with DANE-TA(2)
+ */
+ if (depth >= ctx->num_untrusted)
+ mask &= DANETLS_PKIX_MASK;
+
+ /*
+ * If we've previously matched a PKIX-?? record, no need to test any
+ * furher PKIX-?? records, it remains to just build the PKIX chain.
+ * Had the match been a DANE-?? record, we'd be done already.
+ */
+ if (dane->mdpth >= 0)
+ mask &= ~DANETLS_PKIX_MASK;
+
+ /*-
+ * https://tools.ietf.org/html/rfc7671#section-5.1
+ * https://tools.ietf.org/html/rfc7671#section-5.2
+ * https://tools.ietf.org/html/rfc7671#section-5.3
+ * https://tools.ietf.org/html/rfc7671#section-5.4
+ *
+ * We handle DANE-EE(3) records first as they require no chain building
+ * and no expiration or hostname checks. We also process digests with
+ * higher ordinals first and ignore lower priorities except Full(0) which
+ * is always processed (last). If none match, we then process PKIX-EE(1).
+ *
+ * NOTE: This relies on DANE usages sorting before the corresponding PKIX
+ * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
+ * priorities. See twin comment in ssl/ssl_lib.c.
+ *
+ * We expect that most TLSA RRsets will have just a single usage, so we
+ * don't go out of our way to cache multiple selector-specific i2d buffers
+ * across usages, but if the selector happens to remain the same as switch
+ * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
+ * records would result in us generating each of the certificate and public
+ * key DER forms twice, but more typically we'd just see multiple "3 1 1"
+ * or multiple "3 0 1" records.
+ *
+ * As soon as we find a match at any given depth, we stop, because either
+ * we've matched a DANE-?? record and the peer is authenticated, or, after
+ * exhausing all DANE-?? records, we've matched a PKIX-?? record, which is
+ * sufficient for DANE, and what remains to do is ordinary PKIX validation.
+ */
+ recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
+ for (i = 0; matched == 0 && i < recnum; ++i) {
+ t = sk_danetls_record_value(dane->trecs, i);
+ if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
+ continue;
+ if (t->usage != usage) {
+ usage = t->usage;
+
+ /* Reset digest agility for each usage/selector pair */
+ mtype = DANETLS_NONE;
+ ordinal = dane->dctx->mdord[t->mtype];
+ }
+ if (t->selector != selector) {
+ selector = t->selector;
+
+ /* Update per-selector state */
+ OPENSSL_free(i2dbuf);
+ i2dbuf = dane_i2d(cert, selector, &i2dlen);
+ if (i2dbuf == NULL)
+ return -1;
+
+ /* Reset digest agility for each usage/selector pair */
+ mtype = DANETLS_NONE;
+ ordinal = dane->dctx->mdord[t->mtype];
+ } else if (t->mtype != DANETLS_MATCHING_FULL) {
+ /*-
+ * Digest agility:
+ *
+ * <https://tools.ietf.org/html/rfc7671#section-9>
+ *
+ * For a fixed selector, after processing all records with the
+ * highest mtype ordinal, ignore all mtypes with lower ordinals
+ * other than "Full".
+ */
+ if (dane->dctx->mdord[t->mtype] < ordinal)
+ continue;
+ }
+
+ /*
+ * Each time we hit a (new selector or) mtype, re-compute the relevant
+ * digest, more complex caching is not worth the code space.
+ */
+ if (t->mtype != mtype) {
+ const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
+ cmpbuf = i2dbuf;
+ cmplen = i2dlen;
+
+ if (md != NULL) {
+ cmpbuf = mdbuf;
+ if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
+ matched = -1;
+ break;
+ }
+ }
+ }
+
+ /*
+ * Squirrel away the certificate and depth if we have a match. Any
+ * DANE match is dispositive, but with PKIX we still need to build a
+ * full chain.
+ */
+ if (cmplen == t->dlen &&
+ memcmp(cmpbuf, t->data, cmplen) == 0) {
+ if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
+ matched = 1;
+ if (matched || dane->mdpth < 0) {
+ dane->mdpth = depth;
+ dane->mtlsa = t;
+ OPENSSL_free(dane->mcert);
+ dane->mcert = cert;
+ X509_up_ref(cert);
+ }
+ break;
+ }
+ }
+
+ /* Clear the one-element DER cache */
+ OPENSSL_free(i2dbuf);
+ return matched;
+}
+
+static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
+{
+ struct dane_st *dane = (struct dane_st *)ctx->dane;
+ int matched = 0;
+ X509 *cert;
+
+ if (!DANETLS_HAS_TA(dane) || depth == 0)
+ return X509_TRUST_UNTRUSTED;
+
+ /*
+ * Record any DANE trust anchor matches, for the first depth to test, if
+ * there's one at that depth. (This'll be false for length 1 chains looking
+ * for an exact match for the leaf certificate).
+ */
+ cert = sk_X509_value(ctx->chain, depth);
+ if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
+ return X509_TRUST_REJECTED;
+ if (matched > 0) {
+ ctx->num_untrusted = depth - 1;
+ return X509_TRUST_TRUSTED;
+ }
+
+ return X509_TRUST_UNTRUSTED;
+}
+
+static int check_dane_pkeys(X509_STORE_CTX *ctx)
+{
+ struct dane_st *dane = (struct dane_st *)ctx->dane;
+ danetls_record *t;
+ int num = ctx->num_untrusted;
+ X509 *cert = sk_X509_value(ctx->chain, num - 1);
+ int recnum = sk_danetls_record_num(dane->trecs);
+ int i;
+
+ for (i = 0; i < recnum; ++i) {
+ t = sk_danetls_record_value(dane->trecs, i);
+ if (t->usage != DANETLS_USAGE_DANE_TA ||
+ t->selector != DANETLS_SELECTOR_SPKI ||
+ t->mtype != DANETLS_MATCHING_FULL ||
+ X509_verify(cert, t->spki) <= 0)
+ continue;
+
+ /* Clear PKIX-?? matches that failed to panned out to a full chain */
+ X509_free(dane->mcert);
+ dane->mcert = NULL;
+
+ /* Record match via a bare TA public key */
+ ctx->bare_ta_signed = 1;
+ dane->mdpth = num - 1;
+ dane->mtlsa = t;
+
+ /* Prune any excess chain certificates */
+ num = sk_X509_num(ctx->chain);
+ for (; num > ctx->num_untrusted; --num)
+ X509_free(sk_X509_pop(ctx->chain));
+
+ return X509_TRUST_TRUSTED;
+ }
+
+ return X509_TRUST_UNTRUSTED;
+}
+
+static void dane_reset(struct dane_st *dane)
+{
+ /*
+ * Reset state to verify another chain, or clear after failure.
+ */
+ X509_free(dane->mcert);
+ dane->mcert = NULL;
+ dane->mtlsa = NULL;
+ dane->mdpth = -1;
+ dane->pdpth = -1;
+}
+
+static int dane_verify(X509_STORE_CTX *ctx)
+{
+ X509 *cert = ctx->cert;
+ int (*cb)(int xok, X509_STORE_CTX *xctx) = ctx->verify_cb;
+ struct dane_st *dane = (struct dane_st *)ctx->dane;
+ int matched;
+ int done;
+
+ dane_reset(dane);
+
+ matched = dane_match(ctx, ctx->cert, 0);
+ done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
+
+ if (done)
+ X509_get_pubkey_parameters(NULL, ctx->chain);
+
+ if (matched > 0) {
+ ctx->error_depth = 0;
+ ctx->current_cert = cert;
+ return cb(1, ctx);
+ }
+
+ if (matched < 0) {
+ ctx->error_depth = 0;
+ ctx->current_cert = cert;
+ ctx->error = X509_V_ERR_OUT_OF_MEM;
+ return -1;
+ }
+
+ if (done) {
+ /* Fail early, TA-based success is not possible */
+ ctx->current_cert = cert;
+ ctx->error_depth = 0;
+ ctx->error = X509_V_ERR_CERT_UNTRUSTED;
+ return cb(0, ctx);
+ }
+
+ /*
+ * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
+ * certificates happens in-line with building the rest of the chain.
+ */
+ return verify_chain(ctx);
+}
+
+static int build_chain(X509_STORE_CTX *ctx)
+{
+ struct dane_st *dane = (struct dane_st *)ctx->dane;
+ int (*cb) (int, X509_STORE_CTX *) = ctx->verify_cb;
+ int num = sk_X509_num(ctx->chain);
+ X509 *cert = sk_X509_value(ctx->chain, num - 1);
+ int ss = cert_self_signed(cert);
+ STACK_OF(X509) *sktmp = NULL;
+ unsigned int search;
+ int may_trusted = 0;
+ int may_alternate = 0;
+ int trust = X509_TRUST_UNTRUSTED;
+ int alt_untrusted = 0;
+ int depth;
+ int ok = 0;
+ int i;
+
+ /* Our chain starts with a single untrusted element. */
+ OPENSSL_assert(num == 1 && ctx->num_untrusted == num);
+
+#define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
+#define S_DOTRUSTED (1 << 1) /* Search trusted store */
+#define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
+ /*
+ * Set up search policy, untrusted if possible, trusted-first if enabled.
+ * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
+ * trust_store, otherwise we might look there first. If not trusted-first,
+ * and alternate chains are not disabled, try building an alternate chain
+ * if no luck with untrusted first.
+ */
+ search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
+ if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
+ if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
+ search |= S_DOTRUSTED;
+ else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
+ may_alternate = 1;
+ may_trusted = 1;
+ }
+
+ /*
+ * Shallow-copy the stack of untrusted certificates (with TLS, this is
+ * typically the content of the peer's certificate message) so can make
+ * multiple passes over it, while free to remove elements as we go.
+ */
+ if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
+ X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+
+ /* Include any untrusted full certificates from DNS */
+ if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
+ for (i = 0; i < sk_X509_num(dane->certs); ++i) {
+ if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
+ sk_X509_free(sktmp);
+ X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ }
+ }
+
+ /*
+ * Still absurdly large, but arithmetically safe, a lower hard upper bound
+ * might be reasonable.
+ */
+ if (ctx->param->depth > INT_MAX/2)
+ ctx->param->depth = INT_MAX/2;
+
+ /*
+ * Try to Extend the chain until we reach an ultimately trusted issuer.
+ * Build chains up to one longer the limit, later fail if we hit the limit,
+ * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
+ */
+ depth = ctx->param->depth + 1;
+
+ while (search != 0) {
+ X509 *x;
+ X509 *xtmp = NULL;
+
+ /*
+ * Look in the trust store if enabled for first lookup, or we've run
+ * out of untrusted issuers and search here is not disabled. When
+ * we exceed the depth limit, we simulate absence of a match.
+ */
+ if ((search & S_DOTRUSTED) != 0) {
+ STACK_OF(X509) *hide = ctx->chain;
+
+ i = num = sk_X509_num(ctx->chain);
+ if ((search & S_DOALTERNATE) != 0) {
+ /*
+ * As high up the chain as we can, look for an alternative
+ * trusted issuer of an untrusted certificate that currently
+ * has an untrusted issuer. We use the alt_untrusted variable
+ * to track how far up the chain we find the first match. It
+ * is only if and when we find a match, that we prune the chain
+ * and reset ctx->num_untrusted to the reduced count of
+ * untrusted certificates. While we're searching for such a
+ * match (which may never be found), it is neither safe nor
+ * wise to preemptively modify either the chain or
+ * ctx->num_untrusted.
+ *
+ * Note, like ctx->num_untrusted, alt_untrusted is a count of
+ * untrusted certificates, not a "depth".
+ */
+ i = alt_untrusted;
+ }
+ x = sk_X509_value(ctx->chain, i-1);
+
+ /* Suppress duplicate suppression */
+ ctx->chain = NULL;
+ ok = (depth < num) ? 0 : ctx->get_issuer(&xtmp, ctx, x);
+ ctx->chain = hide;
+
+ if (ok < 0) {
+ trust = X509_TRUST_REJECTED;
+ search = 0;
+ continue;
+ }
+
+ if (ok > 0) {
+ /*
+ * Alternative trusted issuer for a mid-chain untrusted cert?
+ * Pop the untrusted cert's successors and retry. We might now
+ * be able to complete a valid chain via the trust store. Note
+ * that despite the current trust-store match we might still
+ * fail complete the chain to a suitable trust-anchor, in which
+ * case we may prune some more untrusted certificates and try
+ * again. Thus the S_DOALTERNATE bit may yet be turned on
+ * again with an even shorter untrusted chain!
+ *
+ * If in the process we threw away our matching PKIX-TA trust
+ * anchor, reset DANE trust. We might find a suitable trusted
+ * certificate among the ones from the trust store.
+ */
+ if ((search & S_DOALTERNATE) != 0) {
+ OPENSSL_assert(num > i && i > 0 && ss == 0);
+ search &= ~S_DOALTERNATE;
+ for (; num > i; --num)
+ X509_free(sk_X509_pop(ctx->chain));
+ ctx->num_untrusted = num;
+
+ if (DANETLS_ENABLED(dane) &&
+ dane->mdpth >= ctx->num_untrusted) {
+ dane->mdpth = -1;
+ X509_free(dane->mcert);
+ dane->mcert = NULL;
+ }
+ if (DANETLS_ENABLED(dane) &&
+ dane->pdpth >= ctx->num_untrusted)
+ dane->pdpth = -1;
+ }
+
+ /*
+ * Self-signed untrusted certificates get replaced by their
+ * trusted matching issuer. Otherwise, grow the chain.
+ */
+ if (ss == 0) {
+ if (!sk_X509_push(ctx->chain, x = xtmp)) {
+ X509_free(xtmp);
+ X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
+ trust = X509_TRUST_REJECTED;
+ search = 0;
+ continue;
+ }
+ ss = cert_self_signed(x);
+ } else if (num == ctx->num_untrusted) {
+ /*
+ * We have a self-signed certificate that has the same
+ * subject name (and perhaps keyid and/or serial number) as
+ * a trust-anchor. We must have an exact match to avoid
+ * possible impersonation via key substitution etc.
+ */
+ if (X509_cmp(x, xtmp) != 0) {
+ /* Self-signed untrusted mimic. */
+ X509_free(xtmp);
+ ok = 0;
+ } else {
+ X509_free(x);
+ ctx->num_untrusted = --num;
+ (void) sk_X509_set(ctx->chain, num, x = xtmp);
+ }
+ }
+
+ /*
+ * We've added a new trusted certificate to the chain, recheck
+ * trust. If not done, and not self-signed look deeper.
+ * Whether or not we're doing "trusted first", we no longer
+ * look for untrusted certificates from the peer's chain.
+ *
+ * At this point ctx->num_trusted and num must reflect the
+ * correct number of untrusted certificates, since the DANE
+ * logic in check_trust() depends on distinguishing CAs from
+ * "the wire" from CAs from the trust store. In particular, the
+ * certificate at depth "num" should be the new trusted
+ * certificate with ctx->num_untrusted <= num.
+ */
+ if (ok) {
+ OPENSSL_assert(ctx->num_untrusted <= num);
+ search &= ~S_DOUNTRUSTED;
+ switch (trust = check_trust(ctx, num)) {
+ case X509_TRUST_TRUSTED:
+ case X509_TRUST_REJECTED:
+ search = 0;
+ continue;
+ }
+ if (ss == 0)
+ continue;
+ }
+ }
+
+ /*
+ * No dispositive decision, and either self-signed or no match, if
+ * we were doing untrusted-first, and alt-chains are not disabled,
+ * do that, by repeatedly losing one untrusted element at a time,
+ * and trying to extend the shorted chain.
+ */
+ if ((search & S_DOUNTRUSTED) == 0) {
+ /* Continue search for a trusted issuer of a shorter chain? */
+ if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
+ continue;
+ /* Still no luck and no fallbacks left? */
+ if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
+ ctx->num_untrusted < 2)
+ break;
+ /* Search for a trusted issuer of a shorter chain */
+ search |= S_DOALTERNATE;
+ alt_untrusted = ctx->num_untrusted - 1;
+ ss = 0;
+ }
+ }
+
+ /*
+ * Extend chain with peer-provided certificates
+ */
+ if ((search & S_DOUNTRUSTED) != 0) {
+ num = sk_X509_num(ctx->chain);
+ OPENSSL_assert(num == ctx->num_untrusted);
+ x = sk_X509_value(ctx->chain, num-1);
+ xtmp = (depth < num) ? NULL : find_issuer(ctx, sktmp, x);
+
+ /*
+ * Once we run out of untrusted issuers, we stop looking for more
+ * and start looking only in the trust store if enabled.
+ */
+ if (xtmp == NULL) {
+ search &= ~S_DOUNTRUSTED;
+ if (may_trusted)
+ search |= S_DOTRUSTED;
+ continue;
+ }
+
+ if (!sk_X509_push(ctx->chain, x = xtmp)) {
+ X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
+ trust = X509_TRUST_REJECTED;
+ search = 0;
+ continue;
+ }
+ X509_up_ref(x);
+ ++ctx->num_untrusted;
+ ss = cert_self_signed(xtmp);
+
+ /*
+ * Not strictly necessary, but saves cycles looking at the same
+ * certificates over and over.
+ */
+ (void) sk_X509_delete_ptr(sktmp, x);
+
+ /*
+ * Check for DANE-TA trust of the topmost untrusted certificate.
+ */
+ switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
+ case X509_TRUST_TRUSTED:
+ case X509_TRUST_REJECTED:
+ search = 0;
+ continue;
+ }
+ }
+ }
+ sk_X509_free(sktmp);
+
+ /*
+ * Last chance to make a trusted chain, either bare DANE-TA public-key
+ * signers, or else direct leaf PKIX trust.
+ */
+ num = sk_X509_num(ctx->chain);
+ if (num <= depth) {
+ if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
+ trust = check_dane_pkeys(ctx);
+ if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
+ trust = check_trust(ctx, num);
+ }
+
+ switch (trust) {
+ case X509_TRUST_TRUSTED:
+ return 1;
+ case X509_TRUST_REJECTED:
+ return 0;
+ case X509_TRUST_UNTRUSTED:
+ default:
+ num = sk_X509_num(ctx->chain);
+ ctx->current_cert = sk_X509_value(ctx->chain, num - 1);
+ ctx->error_depth = num-1;
+ if (num > depth)
+ ctx->error = X509_V_ERR_CERT_CHAIN_TOO_LONG;
+ else if (DANETLS_ENABLED(dane) &&
+ (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
+ ctx->error = X509_V_ERR_CERT_UNTRUSTED;
+ else if (ss && sk_X509_num(ctx->chain) == 1)
+ ctx->error = X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;
+ else if (ss)
+ ctx->error = X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN;
+ else if (ctx->num_untrusted == num)
+ ctx->error = X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY;
+ else
+ ctx->error = X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT;
+ if (DANETLS_ENABLED(dane))
+ dane_reset(dane);
+ return cb(0, ctx);
+ }
+}
projects / openssl.git / blobdiff