/* $OpenBSD: x509_vfy.c,v 1.72 2019/03/06 05:06:58 tb Exp $ */ /* 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "asn1_locl.h" #include "vpm_int.h" #include "x509_lcl.h" /* CRL score values */ /* No unhandled critical extensions */ #define CRL_SCORE_NOCRITICAL 0x100 /* certificate is within CRL scope */ #define CRL_SCORE_SCOPE 0x080 /* CRL times valid */ #define CRL_SCORE_TIME 0x040 /* Issuer name matches certificate */ #define CRL_SCORE_ISSUER_NAME 0x020 /* If this score or above CRL is probably valid */ #define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE) /* CRL issuer is certificate issuer */ #define CRL_SCORE_ISSUER_CERT 0x018 /* CRL issuer is on certificate path */ #define CRL_SCORE_SAME_PATH 0x008 /* CRL issuer matches CRL AKID */ #define CRL_SCORE_AKID 0x004 /* Have a delta CRL with valid times */ #define CRL_SCORE_TIME_DELTA 0x002 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_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 get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer, unsigned int *preasons, X509_CRL *crl, X509 *x); static int get_crl_delta(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x); static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pcrl_score, X509_CRL *base, STACK_OF(X509_CRL) *crls); static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer, int *pcrl_score); static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score, unsigned int *preasons); static int check_crl_path(X509_STORE_CTX *ctx, X509 *x); static int check_crl_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *cert_path, STACK_OF(X509) *crl_path); static int X509_cmp_time_internal(const ASN1_TIME *ctm, time_t *cmp_time, int clamp_notafter); static int internal_verify(X509_STORE_CTX *ctx); int ASN1_time_tm_clamp_notafter(struct tm *tm); 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 /* Return 1 if a certificate is self signed */ static int cert_self_signed(X509 *x) { X509_check_purpose(x, -1, 0); if (x->ex_flags & EXFLAG_SS) return 1; else return 0; } static int check_id_error(X509_STORE_CTX *ctx, int errcode) { ctx->error = errcode; ctx->current_cert = ctx->cert; ctx->error_depth = 0; return ctx->verify_cb(0, ctx); } static int check_hosts(X509 *x, X509_VERIFY_PARAM_ID *id) { size_t i, n; char *name; n = sk_OPENSSL_STRING_num(id->hosts); free(id->peername); id->peername = NULL; for (i = 0; i < n; ++i) { name = sk_OPENSSL_STRING_value(id->hosts, i); if (X509_check_host(x, name, strlen(name), id->hostflags, &id->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 (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH)) return 0; } if (id->email != NULL && X509_check_email(x, id->email, id->emaillen, 0) <= 0) { if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH)) return 0; } if (id->ip != NULL && X509_check_ip(x, id->ip, id->iplen, 0) <= 0) { if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH)) return 0; } return 1; } int X509_verify_cert(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, trust; int (*cb) (int xok, X509_STORE_CTX *xctx); STACK_OF(X509) *sktmp = NULL; if (ctx->cert == NULL) { X509error(X509_R_NO_CERT_SET_FOR_US_TO_VERIFY); ctx->error = X509_V_ERR_INVALID_CALL; return -1; } if (ctx->chain != NULL) { /* * This X509_STORE_CTX has already been used to verify * a cert. We cannot do another one. */ X509error(ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); ctx->error = X509_V_ERR_INVALID_CALL; return -1; } if (ctx->param->id->poisoned) { /* * This X509_STORE_CTX had failures setting * up verify parameters. We can not use it. */ X509error(ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); ctx->error = X509_V_ERR_INVALID_CALL; return -1; } if (ctx->error != X509_V_ERR_INVALID_CALL) { /* * This X509_STORE_CTX has not been properly initialized. */ X509error(ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); ctx->error = X509_V_ERR_INVALID_CALL; return -1; } ctx->error = X509_V_OK; /* Initialize to OK */ 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. */ ctx->chain = sk_X509_new_null(); if (ctx->chain == NULL || !sk_X509_push(ctx->chain, ctx->cert)) { X509error(ERR_R_MALLOC_FAILURE); ctx->error = X509_V_ERR_OUT_OF_MEM; goto end; } X509_up_ref(ctx->cert); 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) { X509error(ERR_R_MALLOC_FAILURE); ctx->error = X509_V_ERR_OUT_OF_MEM; 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 */ /* 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 (depth < num) break; /* 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) { ctx->error = X509_V_ERR_STORE_LOOKUP; goto end; } /* * 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)) { X509error(ERR_R_MALLOC_FAILURE); ctx->error = X509_V_ERR_OUT_OF_MEM; ok = 0; goto end; } X509_up_ref(xtmp); (void)sk_X509_delete_ptr(sktmp, xtmp); ctx->last_untrusted++; x = xtmp; num++; /* * reparse the full chain for the next one */ continue; } } break; } /* 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. */ 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 (i == 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 (ok < 0) { ctx->error = X509_V_ERR_STORE_LOOKUP; goto end; } if (ok == 0) break; x = xtmp; if (!sk_X509_push(ctx->chain, x)) { X509_free(xtmp); X509error(ERR_R_MALLOC_FAILURE); ctx->error = X509_V_ERR_OUT_OF_MEM; ok = 0; goto end; } num++; } /* we now have our chain, lets check it... */ trust = check_trust(ctx); /* If explicitly rejected error */ if (trust == X509_TRUST_REJECTED) { ok = 0; goto end; } /* * 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 */ retry = 0; if (trust != X509_TRUST_TRUSTED && !(ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST) && !(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS)) { while (j-- > 1) { xtmp2 = sk_X509_value(ctx->chain, j - 1); ok = ctx->get_issuer(&xtmp, ctx, xtmp2); 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 = sk_X509_num(ctx->chain); retry = 1; break; } } } } while (retry); /* * 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 */ if (trust != 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 { if (!sk_X509_push(ctx->chain, chain_ss)) { X509error(ERR_R_MALLOC_FAILURE); ctx->error = X509_V_ERR_OUT_OF_MEM; ok = 0; goto end; } 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; /* Check name constraints */ ok = check_name_constraints(ctx); if (!ok) goto end; ok = check_id(ctx); if (!ok) goto end; /* * 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; /* If we get this far evaluate policies */ if (!bad_chain && (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)) ok = ctx->check_policy(ctx); end: sk_X509_free(sktmp); X509_free(chain_ss); /* Safety net, error returns must set ctx->error */ if (ok <= 0 && ctx->error == X509_V_OK) ctx->error = X509_V_ERR_UNSPECIFIED; 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, *rv = NULL; for (i = 0; i < sk_X509_num(sk); i++) { issuer = sk_X509_value(sk, i); if (ctx->check_issued(ctx, x, issuer)) { rv = issuer; if (x509_check_cert_time(ctx, rv, -1)) break; } } return rv; } /* 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); } /* 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 purpose; int 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; /* CRL path validation */ if (ctx->parent) { allow_proxy_certs = 0; purpose = X509_PURPOSE_CRL_SIGN; } else { allow_proxy_certs = !!(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS); purpose = ctx->param->purpose; } /* 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, 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_name_constraints(X509_STORE_CTX *ctx) { X509 *x; int i, j, rv; /* Check name constraints for all certificates */ for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) { x = sk_X509_value(ctx->chain, i); /* Ignore self issued certs unless last in chain */ if (i && (x->ex_flags & EXFLAG_SI)) continue; /* Check against constraints for all certificates higher in * chain including trust anchor. Trust anchor not strictly * speaking needed but if it includes constraints it is to be * assumed it expects them to be obeyed. */ for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) { NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc; if (nc) { rv = NAME_CONSTRAINTS_check(x, nc); if (rv != X509_V_OK) { ctx->error = rv; ctx->error_depth = i; ctx->current_cert = x; if (!ctx->verify_cb(0, ctx)) return 0; } } } } return 1; } /* Given a certificate try and find an exact match in the store */ static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x) { STACK_OF(X509) *certs; X509 *xtmp = NULL; size_t i; /* Lookup all certs with matching subject name */ certs = ctx->lookup_certs(ctx, X509_get_subject_name(x)); if (certs == NULL) return NULL; /* Look for exact match */ for (i = 0; i < sk_X509_num(certs); i++) { xtmp = sk_X509_value(certs, i); if (!X509_cmp(xtmp, x)) break; } if (i < sk_X509_num(certs)) X509_up_ref(xtmp); else xtmp = NULL; sk_X509_pop_free(certs, X509_free); return xtmp; } static int check_trust(X509_STORE_CTX *ctx) { size_t i; int ok; 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++) { x = sk_X509_value(ctx->chain, i); ok = 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 we accept partial chains and have at least one trusted certificate * return success. */ if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) { X509 *mx; if (ctx->last_untrusted < (int)sk_X509_num(ctx->chain)) return X509_TRUST_TRUSTED; x = sk_X509_value(ctx->chain, 0); 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 no trusted certs in chain at all return untrusted and allow * standard (no issuer cert) etc errors to be indicated. */ return X509_TRUST_UNTRUSTED; } 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 { /* If checking CRL paths this isn't the EE certificate */ if (ctx->parent) return 1; 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, *dcrl = NULL; X509 *x; int ok = 0, cnum; unsigned int last_reasons; cnum = ctx->error_depth; x = sk_X509_value(ctx->chain, cnum); ctx->current_cert = x; ctx->current_issuer = NULL; ctx->current_crl_score = 0; ctx->current_reasons = 0; while (ctx->current_reasons != CRLDP_ALL_REASONS) { last_reasons = ctx->current_reasons; /* Try to retrieve relevant CRL */ if (ctx->get_crl) ok = ctx->get_crl(ctx, &crl, x); else ok = get_crl_delta(ctx, &crl, &dcrl, 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; if (dcrl) { ok = ctx->check_crl(ctx, dcrl); if (!ok) goto err; ok = ctx->cert_crl(ctx, dcrl, x); if (!ok) goto err; } else ok = 1; /* Don't look in full CRL if delta reason is removefromCRL */ if (ok != 2) { ok = ctx->cert_crl(ctx, crl, x); if (!ok) goto err; } ctx->current_crl = NULL; X509_CRL_free(crl); X509_CRL_free(dcrl); crl = NULL; dcrl = NULL; /* If reasons not updated we wont get anywhere by * another iteration, so exit loop. */ if (last_reasons == ctx->current_reasons) { ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL; ok = ctx->verify_cb(0, ctx); goto err; } } err: ctx->current_crl = NULL; X509_CRL_free(crl); X509_CRL_free(dcrl); 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 = NULL; int i; if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME) return (1); if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME) ptime = &ctx->param->check_time; if (notify) ctx->current_crl = crl; i = X509_cmp_time(X509_CRL_get_lastUpdate(crl), ptime); if (i == 0) { if (!notify) return 0; ctx->error = X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD; if (!ctx->verify_cb(0, ctx)) return 0; } if (i > 0) { if (!notify) return 0; ctx->error = X509_V_ERR_CRL_NOT_YET_VALID; if (!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) { if (!notify) return 0; ctx->error = X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD; if (!ctx->verify_cb(0, ctx)) return 0; } /* Ignore expiry of base CRL is delta is valid */ if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) { if (!notify) return 0; ctx->error = X509_V_ERR_CRL_HAS_EXPIRED; if (!ctx->verify_cb(0, ctx)) return 0; } } if (notify) ctx->current_crl = NULL; return 1; } static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl, X509 **pissuer, int *pscore, unsigned int *preasons, STACK_OF(X509_CRL) *crls) { int i, crl_score, best_score = *pscore; unsigned int reasons, best_reasons = 0; X509 *x = ctx->current_cert; X509_CRL *crl, *best_crl = NULL; X509 *crl_issuer = NULL, *best_crl_issuer = NULL; for (i = 0; i < sk_X509_CRL_num(crls); i++) { crl = sk_X509_CRL_value(crls, i); reasons = *preasons; crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x); if (crl_score > best_score) { best_crl = crl; best_crl_issuer = crl_issuer; best_score = crl_score; best_reasons = reasons; } } if (best_crl) { if (*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; } get_delta_sk(ctx, pdcrl, pscore, best_crl, crls); } if (best_score >= CRL_SCORE_VALID) return 1; return 0; } /* Compare two CRL extensions for delta checking purposes. They should be * both present or both absent. If both present all fields must be identical. */ static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid) { ASN1_OCTET_STRING *exta, *extb; int i; i = X509_CRL_get_ext_by_NID(a, nid, -1); if (i >= 0) { /* Can't have multiple occurrences */ if (X509_CRL_get_ext_by_NID(a, nid, i) != -1) return 0; exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i)); } else exta = NULL; i = X509_CRL_get_ext_by_NID(b, nid, -1); if (i >= 0) { if (X509_CRL_get_ext_by_NID(b, nid, i) != -1) return 0; extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i)); } else extb = NULL; if (!exta && !extb) return 1; if (!exta || !extb) return 0; if (ASN1_OCTET_STRING_cmp(exta, extb)) return 0; return 1; } /* See if a base and delta are compatible */ static int check_delta_base(X509_CRL *delta, X509_CRL *base) { /* Delta CRL must be a delta */ if (!delta->base_crl_number) return 0; /* Base must have a CRL number */ if (!base->crl_number) return 0; /* Issuer names must match */ if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta))) return 0; /* AKID and IDP must match */ if (!crl_extension_match(delta, base, NID_authority_key_identifier)) return 0; if (!crl_extension_match(delta, base, NID_issuing_distribution_point)) return 0; /* Delta CRL base number must not exceed Full CRL number. */ if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0) return 0; /* Delta CRL number must exceed full CRL number */ if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0) return 1; return 0; } /* For a given base CRL find a delta... maybe extend to delta scoring * or retrieve a chain of deltas... */ static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore, X509_CRL *base, STACK_OF(X509_CRL) *crls) { X509_CRL *delta; int i; if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS)) return; if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST)) return; for (i = 0; i < sk_X509_CRL_num(crls); i++) { delta = sk_X509_CRL_value(crls, i); 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); *dcrl = delta; return; } } *dcrl = NULL; } /* For a given CRL return how suitable it is for the supplied certificate 'x'. * The return value is a mask of several criteria. * If the issuer is not the certificate issuer this is returned in *pissuer. * The reasons mask is also used to determine if the CRL is suitable: if * no new reasons the CRL is rejected, otherwise reasons is updated. */ static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer, unsigned int *preasons, X509_CRL *crl, X509 *x) { int crl_score = 0; unsigned int tmp_reasons = *preasons, crl_reasons; /* First see if we can reject CRL straight away */ /* Invalid IDP cannot be processed */ if (crl->idp_flags & IDP_INVALID) return 0; /* Reason codes or indirect CRLs need extended CRL support */ if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) { if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS)) return 0; } else if (crl->idp_flags & IDP_REASONS) { /* If no new reasons reject */ if (!(crl->idp_reasons & ~tmp_reasons)) return 0; } /* Don't process deltas at this stage */ else if (crl->base_crl_number) return 0; /* If issuer name doesn't match certificate need indirect CRL */ if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) { if (!(crl->idp_flags & IDP_INDIRECT)) return 0; } else crl_score |= CRL_SCORE_ISSUER_NAME; if (!(crl->flags & EXFLAG_CRITICAL)) crl_score |= CRL_SCORE_NOCRITICAL; /* Check expiry */ if (check_crl_time(ctx, crl, 0)) crl_score |= CRL_SCORE_TIME; /* Check authority key ID and locate certificate issuer */ crl_akid_check(ctx, crl, pissuer, &crl_score); /* If we can't locate certificate issuer at this point forget it */ if (!(crl_score & CRL_SCORE_AKID)) return 0; /* Check cert for matching CRL distribution points */ if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) { /* If no new reasons reject */ if (!(crl_reasons & ~tmp_reasons)) return 0; tmp_reasons |= crl_reasons; crl_score |= CRL_SCORE_SCOPE; } *preasons = tmp_reasons; return crl_score; } static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer, int *pcrl_score) { X509 *crl_issuer = NULL; X509_NAME *cnm = X509_CRL_get_issuer(crl); int cidx = ctx->error_depth; int i; if (cidx != sk_X509_num(ctx->chain) - 1) cidx++; crl_issuer = sk_X509_value(ctx->chain, cidx); if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) { if (*pcrl_score & CRL_SCORE_ISSUER_NAME) { *pcrl_score |= CRL_SCORE_AKID|CRL_SCORE_ISSUER_CERT; *pissuer = crl_issuer; return; } } for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) { crl_issuer = sk_X509_value(ctx->chain, cidx); if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm)) continue; if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) { *pcrl_score |= CRL_SCORE_AKID|CRL_SCORE_SAME_PATH; *pissuer = crl_issuer; return; } } /* Anything else needs extended CRL support */ if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) return; /* Otherwise the CRL issuer is not on the path. Look for it in the * set of untrusted certificates. */ for (i = 0; i < sk_X509_num(ctx->untrusted); i++) { crl_issuer = sk_X509_value(ctx->untrusted, i); if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm)) continue; if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) { *pissuer = crl_issuer; *pcrl_score |= CRL_SCORE_AKID; return; } } } /* Check the path of a CRL issuer certificate. This creates a new * X509_STORE_CTX and populates it with most of the parameters from the * parent. This could be optimised somewhat since a lot of path checking * will be duplicated by the parent, but this will rarely be used in * practice. */ static int check_crl_path(X509_STORE_CTX *ctx, X509 *x) { X509_STORE_CTX crl_ctx; int ret; /* Don't allow recursive CRL path validation */ if (ctx->parent) return 0; if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted)) { ret = -1; goto err; } crl_ctx.crls = ctx->crls; /* Copy verify params across */ X509_STORE_CTX_set0_param(&crl_ctx, ctx->param); crl_ctx.parent = ctx; crl_ctx.verify_cb = ctx->verify_cb; /* Verify CRL issuer */ ret = X509_verify_cert(&crl_ctx); if (ret <= 0) goto err; /* Check chain is acceptable */ ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain); err: X509_STORE_CTX_cleanup(&crl_ctx); return ret; } /* RFC3280 says nothing about the relationship between CRL path * and certificate path, which could lead to situations where a * certificate could be revoked or validated by a CA not authorised * to do so. RFC5280 is more strict and states that the two paths must * end in the same trust anchor, though some discussions remain... * until this is resolved we use the RFC5280 version */ static int check_crl_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *cert_path, STACK_OF(X509) *crl_path) { X509 *cert_ta, *crl_ta; cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1); crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1); if (!X509_cmp(cert_ta, crl_ta)) return 1; return 0; } /* Check for match between two dist point names: three separate cases. * 1. Both are relative names and compare X509_NAME types. * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES. * 3. Both are full names and compare two GENERAL_NAMES. * 4. One is NULL: automatic match. */ static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b) { X509_NAME *nm = NULL; GENERAL_NAMES *gens = NULL; GENERAL_NAME *gena, *genb; int i, j; if (!a || !b) return 1; if (a->type == 1) { if (!a->dpname) return 0; /* Case 1: two X509_NAME */ if (b->type == 1) { if (!b->dpname) return 0; if (!X509_NAME_cmp(a->dpname, b->dpname)) return 1; else return 0; } /* Case 2: set name and GENERAL_NAMES appropriately */ nm = a->dpname; gens = b->name.fullname; } else if (b->type == 1) { if (!b->dpname) return 0; /* Case 2: set name and GENERAL_NAMES appropriately */ gens = a->name.fullname; nm = b->dpname; } /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */ if (nm) { for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) { gena = sk_GENERAL_NAME_value(gens, i); if (gena->type != GEN_DIRNAME) continue; if (!X509_NAME_cmp(nm, gena->d.directoryName)) return 1; } return 0; } /* Else case 3: two GENERAL_NAMES */ for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) { gena = sk_GENERAL_NAME_value(a->name.fullname, i); for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) { genb = sk_GENERAL_NAME_value(b->name.fullname, j); if (!GENERAL_NAME_cmp(gena, genb)) return 1; } } return 0; } static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score) { int i; X509_NAME *nm = X509_CRL_get_issuer(crl); /* If no CRLissuer return is successful iff don't need a match */ if (!dp->CRLissuer) return !!(crl_score & CRL_SCORE_ISSUER_NAME); for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) { GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i); if (gen->type != GEN_DIRNAME) continue; if (!X509_NAME_cmp(gen->d.directoryName, nm)) return 1; } return 0; } /* Check CRLDP and IDP */ static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score, unsigned int *preasons) { int i; if (crl->idp_flags & IDP_ONLYATTR) return 0; if (x->ex_flags & EXFLAG_CA) { if (crl->idp_flags & IDP_ONLYUSER) return 0; } else { if (crl->idp_flags & IDP_ONLYCA) return 0; } *preasons = crl->idp_reasons; for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) { DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i); if (crldp_check_crlissuer(dp, crl, crl_score)) { if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) { *preasons &= dp->dp_reasons; return 1; } } } if ((!crl->idp || !crl->idp->distpoint) && (crl_score & CRL_SCORE_ISSUER_NAME)) return 1; return 0; } /* Retrieve CRL corresponding to current certificate. * If deltas enabled try to find a delta CRL too */ static int get_crl_delta(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x) { int ok; X509 *issuer = NULL; int crl_score = 0; unsigned int reasons; X509_CRL *crl = NULL, *dcrl = NULL; STACK_OF(X509_CRL) *skcrl; X509_NAME *nm = X509_get_issuer_name(x); reasons = ctx->current_reasons; ok = get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, ctx->crls); if (ok) goto done; /* Lookup CRLs from store */ skcrl = ctx->lookup_crls(ctx, nm); /* If no CRLs found and a near match from get_crl_sk use that */ if (!skcrl && crl) goto done; get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl); sk_X509_CRL_pop_free(skcrl, X509_CRL_free); done: /* If we got any kind of CRL use it and return success */ if (crl) { ctx->current_issuer = issuer; ctx->current_crl_score = crl_score; ctx->current_reasons = reasons; *pcrl = crl; *pdcrl = dcrl; return 1; } return 0; } /* 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; /* if we have an alternative CRL issuer cert use that */ if (ctx->current_issuer) { issuer = ctx->current_issuer; } else if (cnum < chnum) { /* Else find CRL issuer: if not last certificate then issuer * is next certificate in chain. */ 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) { /* Skip most tests for deltas because they have already * been done */ if (!crl->base_crl_number) { /* 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; } if (!(ctx->current_crl_score & CRL_SCORE_SCOPE)) { ctx->error = X509_V_ERR_DIFFERENT_CRL_SCOPE; ok = ctx->verify_cb(0, ctx); if (!ok) goto err; } if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH)) { if (check_crl_path(ctx, ctx->current_issuer) <= 0) { ctx->error = X509_V_ERR_CRL_PATH_VALIDATION_ERROR; ok = ctx->verify_cb(0, ctx); if (!ok) goto err; } } if (crl->idp_flags & IDP_INVALID) { ctx->error = X509_V_ERR_INVALID_EXTENSION; ok = ctx->verify_cb(0, ctx); if (!ok) goto err; } } if (!(ctx->current_crl_score & CRL_SCORE_TIME)) { ok = check_crl_time(ctx, crl, 1); 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 = 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 ok; X509_REVOKED *rev; /* The rules changed for this... previously if a CRL contained * unhandled critical extensions it could still be used to indicate * a certificate was revoked. This has since been changed since * critical extension can change the meaning of CRL entries. */ if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL) && (crl->flags & EXFLAG_CRITICAL)) { ctx->error = X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION; ok = ctx->verify_cb(0, ctx); if (!ok) return 0; } /* Look for serial number of certificate in CRL * If found make sure reason is not removeFromCRL. */ if (X509_CRL_get0_by_cert(crl, &rev, x)) { if (rev->reason == CRL_REASON_REMOVE_FROM_CRL) return 2; ctx->error = X509_V_ERR_CERT_REVOKED; ok = ctx->verify_cb(0, ctx); if (!ok) return 0; } return 1; } static int check_policy(X509_STORE_CTX *ctx) { int ret; if (ctx->parent) return 1; ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain, ctx->param->policies, ctx->param->flags); if (ret == 0) { X509error(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; if (!ctx->verify_cb(0, ctx)) return 0; } 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; } /* * Inform the verify callback of an error. * * If x is not NULL it is the error cert, otherwise use the chain cert * at depth. * * If err is not X509_V_OK, that's the error value, otherwise leave * unchanged (presumably set by the caller). * * Returns 0 to abort verification with an error, non-zero to continue. */ static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err) { ctx->error_depth = depth; ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth); if (err != X509_V_OK) ctx->error = err; return ctx->verify_cb(0, ctx); } /* * Check certificate validity times. * * If depth >= 0, invoke verification callbacks on error, otherwise just return * the validation status. * * Return 1 on success, 0 otherwise. */ int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth) { time_t *ptime; int i; 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; i = X509_cmp_time(X509_get_notBefore(x), ptime); if (i >= 0 && depth < 0) return 0; if (i == 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD)) return 0; if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID)) return 0; i = X509_cmp_time_internal(X509_get_notAfter(x), ptime, 1); if (i <= 0 && depth < 0) return 0; if (i == 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD)) return 0; if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED)) return 0; return 1; } static int internal_verify(X509_STORE_CTX *ctx) { int n = sk_X509_num(ctx->chain) - 1; X509 *xi = sk_X509_value(ctx->chain, n); X509 *xs; if (ctx->check_issued(ctx, xi, xi)) xs = xi; else { if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) { xs = xi; goto check_cert; } if (n <= 0) return verify_cb_cert(ctx, xi, 0, X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE); n--; ctx->error_depth = n; xs = sk_X509_value(ctx->chain, n); } /* * 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) { /* * Skip signature check for self signed certificates * unless explicitly asked for. It doesn't add any * security and just wastes time. If the issuer's * public key is unusable, report the issuer * certificate and its depth (rather than the depth of * the subject). */ if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) { EVP_PKEY *pkey; if ((pkey = X509_get_pubkey(xi)) == NULL) { if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY)) return 0; } else if (X509_verify(xs, pkey) <= 0) { if (!verify_cb_cert(ctx, xs, n, X509_V_ERR_CERT_SIGNATURE_FAILURE)) { EVP_PKEY_free(pkey); return 0; } } EVP_PKEY_free(pkey); } check_cert: /* Calls verify callback as needed */ if (!x509_check_cert_time(ctx, xs, n)) return 0; /* * Signal success at this depth. However, the * previous error (if any) is retained. */ ctx->current_issuer = xi; ctx->current_cert = xs; ctx->error_depth = n; if (!ctx->verify_cb(1, ctx)) return 0; if (--n >= 0) { xi = xs; xs = sk_X509_value(ctx->chain, n); } } return 1; } int X509_cmp_current_time(const ASN1_TIME *ctm) { return X509_cmp_time(ctm, NULL); } /* * Compare a possibly unvalidated ASN1_TIME string against a time_t * using RFC 5280 rules for the time string. If *cmp_time is NULL * the current system time is used. * * XXX NOTE that unlike what you expect a "cmp" function to do in C, * XXX this one is "special", and returns 0 for error. * * Returns: * -1 if the ASN1_time is earlier than OR the same as *cmp_time. * 1 if the ASN1_time is later than *cmp_time. * 0 on error. */ static int X509_cmp_time_internal(const ASN1_TIME *ctm, time_t *cmp_time, int clamp_notafter) { time_t time1, time2; struct tm tm1, tm2; int ret = 0; int type; if (cmp_time == NULL) time2 = time(NULL); else time2 = *cmp_time; memset(&tm1, 0, sizeof(tm1)); type = ASN1_time_parse(ctm->data, ctm->length, &tm1, ctm->type); if (type == -1) goto out; /* invalid time */ /* RFC 5280 section 4.1.2.5 */ if (tm1.tm_year < 150 && type != V_ASN1_UTCTIME) goto out; if (tm1.tm_year >= 150 && type != V_ASN1_GENERALIZEDTIME) goto out; if (clamp_notafter) { /* Allow for completely broken operating systems. */ if (!ASN1_time_tm_clamp_notafter(&tm1)) goto out; } /* * Defensively fail if the time string is not representable as * a time_t. A time_t must be sane if you care about times after * Jan 19 2038. */ if ((time1 = timegm(&tm1)) == -1) goto out; if (gmtime_r(&time2, &tm2) == NULL) goto out; ret = ASN1_time_tm_cmp(&tm1, &tm2); if (ret == 0) ret = -1; /* 0 is used for error, so map same to less than */ out: return (ret); } int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time) { return X509_cmp_time_internal(ctm, cmp_time, 0); } 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 offset_sec, time_t *in_time) { return X509_time_adj_ex(s, 0, offset_sec, in_time); } ASN1_TIME * X509_time_adj_ex(ASN1_TIME *s, int offset_day, long offset_sec, time_t *in_time) { time_t t; if (in_time == NULL) t = time(NULL); else t = *in_time; return ASN1_TIME_adj(s, t, offset_day, offset_sec); } 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) { X509error(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) { X509error(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_get0_chain(X509_STORE_CTX *xs) { return xs->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; } X509 * X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx) { return ctx->current_issuer; } X509_CRL * X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx) { return ctx->current_crl; } X509_STORE_CTX * X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx) { return ctx->parent; } X509_STORE * X509_STORE_CTX_get0_store(X509_STORE_CTX *xs) { return xs->ctx; } 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) { X509error(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) { X509error(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) { X509error(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 = calloc(1, sizeof(X509_STORE_CTX)); if (!ctx) { X509error(ERR_R_MALLOC_FAILURE); return NULL; } return ctx; } void X509_STORE_CTX_free(X509_STORE_CTX *ctx) { if (ctx == NULL) return; X509_STORE_CTX_cleanup(ctx); free(ctx); } int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509, STACK_OF(X509) *chain) { int param_ret = 1; /* * Make sure everything is initialized properly even in case of an * early return due to an error. * * While this 'ctx' can be reused, X509_STORE_CTX_cleanup() will have * freed everything and memset ex_data anyway. This also allows us * to safely use X509_STORE_CTX variables from the stack which will * have uninitialized data. */ memset(ctx, 0, sizeof(*ctx)); /* * Start with this set to not valid - it will be set to valid * in X509_verify_cert. */ ctx->error = X509_V_ERR_INVALID_CALL; /* * Set values other than 0. Keep this in the same order as * X509_STORE_CTX except for values that may fail. All fields that * may fail should go last to make sure 'ctx' is as consistent as * possible even on early exits. */ ctx->ctx = store; ctx->cert = x509; ctx->untrusted = chain; if (store && store->verify) ctx->verify = store->verify; else ctx->verify = internal_verify; if (store && store->verify_cb) ctx->verify_cb = store->verify_cb; else ctx->verify_cb = null_callback; if (store && store->get_issuer) ctx->get_issuer = store->get_issuer; else ctx->get_issuer = X509_STORE_CTX_get1_issuer; if (store && store->check_issued) ctx->check_issued = store->check_issued; else ctx->check_issued = check_issued; 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 = NULL; 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; if (store && store->lookup_certs) ctx->lookup_certs = store->lookup_certs; else ctx->lookup_certs = X509_STORE_get1_certs; if (store && store->lookup_crls) ctx->lookup_crls = store->lookup_crls; else ctx->lookup_crls = X509_STORE_get1_crls; if (store && store->cleanup) ctx->cleanup = store->cleanup; else ctx->cleanup = NULL; ctx->param = X509_VERIFY_PARAM_new(); if (!ctx->param) { X509error(ERR_R_MALLOC_FAILURE); return 0; } /* Inherit callbacks and flags from X509_STORE if not set * use defaults. */ if (store) param_ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param); else ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT|X509_VP_FLAG_ONCE; if (param_ret) param_ret = X509_VERIFY_PARAM_inherit(ctx->param, X509_VERIFY_PARAM_lookup("default")); if (param_ret == 0) { X509error(ERR_R_MALLOC_FAILURE); return 0; } if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data)) == 0) { X509error(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_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk) { X509_STORE_CTX_trusted_stack(ctx, sk); } void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx) { if (ctx->cleanup) ctx->cleanup(ctx); 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; } 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 * X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx) { return ctx->cert; } STACK_OF(X509) * X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx) { return ctx->untrusted; } void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk) { ctx->untrusted = sk; } 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; }