ref: bfe9da47cfa2f51ebef78c59332b5ba2deba306d
dir: /third_party/boringssl/src/crypto/x509/x509_vfy.c/
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ #include <ctype.h> #include <string.h> #include <time.h> #include <openssl/asn1.h> #include <openssl/err.h> #include <openssl/evp.h> #include <openssl/mem.h> #include <openssl/obj.h> #include <openssl/thread.h> #include <openssl/x509.h> #include <openssl/x509v3.h> #include "internal.h" #include "../internal.h" #include "../x509v3/internal.h" static CRYPTO_EX_DATA_CLASS g_ex_data_class = CRYPTO_EX_DATA_CLASS_INIT_WITH_APP_DATA; /* 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_id(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 internal_verify(X509_STORE_CTX *ctx); static int null_callback(int ok, X509_STORE_CTX *e) { return ok; } /* cert_self_signed checks if |x| is self-signed. If |x| is valid, it returns * one and sets |*out_is_self_signed| to the result. If |x| is invalid, it * returns zero. */ static int cert_self_signed(X509 *x, int *out_is_self_signed) { if (!x509v3_cache_extensions(x)) { return 0; } *out_is_self_signed = (x->ex_flags & EXFLAG_SS) != 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; } 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) { OPENSSL_PUT_ERROR(X509, 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. */ OPENSSL_PUT_ERROR(X509, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); ctx->error = X509_V_ERR_INVALID_CALL; return -1; } cb = ctx->verify_cb; /* * first we make sure the chain we are going to build is present and that * the first entry is in place */ ctx->chain = sk_X509_new_null(); if (ctx->chain == NULL || !sk_X509_push(ctx->chain, ctx->cert)) { OPENSSL_PUT_ERROR(X509, 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) { OPENSSL_PUT_ERROR(X509, 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 */ 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. */ int is_self_signed; if (!cert_self_signed(x, &is_self_signed)) { ctx->error = X509_V_ERR_INVALID_EXTENSION; goto end; } /* If we are self signed, we break */ if (is_self_signed) 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 (sktmp != NULL) { xtmp = find_issuer(ctx, sktmp, x); if (xtmp != NULL) { if (!sk_X509_push(ctx->chain, xtmp)) { OPENSSL_PUT_ERROR(X509, 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); int is_self_signed; if (!cert_self_signed(x, &is_self_signed)) { ctx->error = X509_V_ERR_INVALID_EXTENSION; goto end; } if (is_self_signed) { /* 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 (!cert_self_signed(x, &is_self_signed)) { ctx->error = X509_V_ERR_INVALID_EXTENSION; goto end; } /* If we are self signed, we break */ if (is_self_signed) 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); OPENSSL_PUT_ERROR(X509, 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 { sk_X509_push(ctx->chain, chain_ss); num++; ctx->last_untrusted = num; ctx->current_cert = chain_ss; ctx->error = X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN; chain_ss = NULL; } ctx->error_depth = num - 1; bad_chain = 1; ok = cb(0, ctx); if (!ok) goto end; } /* We have the chain complete: now we need to check its purpose */ ok = check_chain_extensions(ctx); if (!ok) goto end; 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; int 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); 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; /* Check name constraints */ ok = check_name_constraints(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: if (sktmp != NULL) sk_X509_free(sktmp); if (chain_ss != NULL) 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) { size_t i; X509 *issuer; for (i = 0; i < sk_X509_num(sk); i++) { issuer = sk_X509_value(sk, i); if (ctx->check_issued(ctx, x, issuer)) return issuer; } return NULL; } /* Given a possible certificate and issuer check them */ static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer) { int ret; ret = X509_check_issued(issuer, x); if (ret == X509_V_OK) return 1; /* If we haven't asked for issuer errors don't set ctx */ if (!(ctx->param->flags & X509_V_FLAG_CB_ISSUER_CHECK)) return 0; ctx->error = ret; ctx->current_cert = x; ctx->current_issuer = issuer; return ctx->verify_cb(0, ctx); } /* 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) { X509_up_ref(*issuer); 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) { int i, ok = 0, 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; enum { // ca_or_leaf allows either type of certificate so that direct use of // self-signed certificates works. ca_or_leaf, must_be_ca, must_not_be_ca, } ca_requirement; /* 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; } ca_requirement = ca_or_leaf; /* 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; } switch (ca_requirement) { case ca_or_leaf: ret = 1; break; case must_not_be_ca: if (X509_check_ca(x)) { ret = 0; ctx->error = X509_V_ERR_INVALID_NON_CA; } else ret = 1; break; case must_be_ca: if (!X509_check_ca(x)) { ret = 0; ctx->error = X509_V_ERR_INVALID_CA; } else ret = 1; break; default: // impossible. ret = 0; } 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, ca_requirement == must_be_ca); if (ret != 1) { ret = 0; 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++; ca_requirement = must_not_be_ca; } else { ca_requirement = must_be_ca; } } ok = 1; end: return ok; } static int reject_dns_name_in_common_name(X509 *x509) { X509_NAME *name = X509_get_subject_name(x509); int i = -1; for (;;) { i = X509_NAME_get_index_by_NID(name, NID_commonName, i); if (i == -1) { return X509_V_OK; } X509_NAME_ENTRY *entry = X509_NAME_get_entry(name, i); ASN1_STRING *common_name = X509_NAME_ENTRY_get_data(entry); unsigned char *idval; int idlen = ASN1_STRING_to_UTF8(&idval, common_name); if (idlen < 0) { return X509_V_ERR_OUT_OF_MEM; } /* Only process attributes that look like host names. Note it is * important that this check be mirrored in |X509_check_host|. */ int looks_like_dns = x509v3_looks_like_dns_name(idval, (size_t)idlen); OPENSSL_free(idval); if (looks_like_dns) { return X509_V_ERR_NAME_CONSTRAINTS_WITHOUT_SANS; } } } static int check_name_constraints(X509_STORE_CTX *ctx) { int i, j, rv; int has_name_constraints = 0; /* Check name constraints for all certificates */ for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) { X509 *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) { has_name_constraints = 1; rv = NAME_CONSTRAINTS_check(x, nc); switch (rv) { case X509_V_OK: continue; case X509_V_ERR_OUT_OF_MEM: ctx->error = rv; return 0; default: ctx->error = rv; ctx->error_depth = i; ctx->current_cert = x; if (!ctx->verify_cb(0, ctx)) return 0; break; } } } } /* Name constraints do not match against the common name, but * |X509_check_host| still implements the legacy behavior where, on * certificates lacking a SAN list, DNS-like names in the common name are * checked instead. * * While we could apply the name constraints to the common name, name * constraints are rare enough that can hold such certificates to a higher * standard. Note this does not make "DNS-like" heuristic failures any * worse. A decorative common-name misidentified as a DNS name would fail * the name constraint anyway. */ X509 *leaf = sk_X509_value(ctx->chain, 0); if (has_name_constraints && leaf->altname == NULL) { rv = reject_dns_name_in_common_name(leaf); switch (rv) { case X509_V_OK: break; case X509_V_ERR_OUT_OF_MEM: ctx->error = rv; return 0; default: ctx->error = rv; ctx->error_depth = i; ctx->current_cert = leaf; if (!ctx->verify_cb(0, ctx)) return 0; break; } } return 1; } 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 *param) { size_t i; size_t n = sk_OPENSSL_STRING_num(param->hosts); char *name; if (param->peername != NULL) { OPENSSL_free(param->peername); param->peername = NULL; } for (i = 0; i < n; ++i) { name = sk_OPENSSL_STRING_value(param->hosts, i); if (X509_check_host(x, name, strlen(name), param->hostflags, ¶m->peername) > 0) return 1; } return n == 0; } static int check_id(X509_STORE_CTX *ctx) { X509_VERIFY_PARAM *vpm = ctx->param; X509 *x = ctx->cert; if (vpm->poison) { if (!check_id_error(ctx, X509_V_ERR_INVALID_CALL)) return 0; } if (vpm->hosts && check_hosts(x, vpm) <= 0) { if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH)) return 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 (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) { 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; } 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: X509_CRL_free(crl); X509_CRL_free(dcrl); ctx->current_crl = NULL; return ok; } /* Check CRL times against values in X509_STORE_CTX */ static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify) { time_t *ptime; int i; if (notify) ctx->current_crl = crl; if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME) ptime = &ctx->param->check_time; else ptime = NULL; i = X509_cmp_time(X509_CRL_get0_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_get0_nextUpdate(crl)) { i = X509_cmp_time(X509_CRL_get0_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 crl_score, best_score = *pscore; size_t i; 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 || crl_score == 0) continue; /* If current CRL is equivalent use it if it is newer */ if (crl_score == best_score && best_crl != NULL) { int day, sec; if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl), X509_CRL_get0_lastUpdate(crl)) == 0) continue; /* * ASN1_TIME_diff never returns inconsistent signs for |day| * and |sec|. */ if (day <= 0 && sec <= 0) continue; } 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; X509_CRL_up_ref(best_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; size_t 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; X509_CRL_up_ref(delta); *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; size_t i; if ((size_t)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 < (int)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)) return -1; 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; } /* * RFC 3280 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. RFC 5280 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 * RFC 5280 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; size_t 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) { size_t 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) { size_t 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 find CRL issuer: if not last certificate then issuer is next * certificate in chain. */ else if (cnum < chnum) issuer = sk_X509_value(ctx->chain, cnum + 1); else { issuer = sk_X509_value(ctx->chain, chnum); /* If not self signed, can't check signature */ if (!ctx->check_issued(ctx, issuer, issuer)) { ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER; ok = ctx->verify_cb(0, ctx); if (!ok) goto err; } } if (issuer) { /* * 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 { int rv; rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags); if (rv != X509_V_OK) { ctx->error = rv; ok = ctx->verify_cb(0, ctx); if (!ok) goto err; } /* 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) { OPENSSL_PUT_ERROR(X509, ERR_R_MALLOC_FAILURE); ctx->error = X509_V_ERR_OUT_OF_MEM; return 0; } /* Invalid or inconsistent extensions */ if (ret == -1) { /* * Locate certificates with bad extensions and notify callback. */ X509 *x; size_t 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; /* * Verification errors need to be "sticky", a callback may have allowed * an SSL handshake to continue despite an error, and we must then * remain in an error state. Therefore, we MUST NOT clear earlier * verification errors by setting the error to X509_V_OK. */ if (!ctx->verify_cb(2, ctx)) return 0; } return 1; } static int check_cert_time(X509_STORE_CTX *ctx, X509 *x) { time_t *ptime; int i; if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME) ptime = &ctx->param->check_time; else ptime = NULL; i = X509_cmp_time(X509_get_notBefore(x), ptime); if (i == 0) { ctx->error = X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD; ctx->current_cert = x; if (!ctx->verify_cb(0, ctx)) return 0; } if (i > 0) { ctx->error = X509_V_ERR_CERT_NOT_YET_VALID; ctx->current_cert = x; if (!ctx->verify_cb(0, ctx)) return 0; } i = X509_cmp_time(X509_get_notAfter(x), ptime); if (i == 0) { ctx->error = X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD; ctx->current_cert = x; if (!ctx->verify_cb(0, ctx)) return 0; } if (i < 0) { ctx->error = X509_V_ERR_CERT_HAS_EXPIRED; ctx->current_cert = x; if (!ctx->verify_cb(0, ctx)) return 0; } return 1; } static int internal_verify(X509_STORE_CTX *ctx) { int ok = 0, n; X509 *xs, *xi; EVP_PKEY *pkey = NULL; int (*cb) (int xok, X509_STORE_CTX *xctx); cb = ctx->verify_cb; n = sk_X509_num(ctx->chain); ctx->error_depth = n - 1; n--; xi = sk_X509_value(ctx->chain, n); if (ctx->check_issued(ctx, xi, xi)) xs = xi; else { if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) { xs = xi; goto check_cert; } if (n <= 0) { ctx->error = X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE; ctx->current_cert = xi; ok = cb(0, ctx); goto end; } else { n--; ctx->error_depth = n; xs = sk_X509_value(ctx->chain, n); } } /* ctx->error=0; not needed */ while (n >= 0) { ctx->error_depth = n; /* * Skip signature check for self signed certificates unless * explicitly asked for. It doesn't add any security and just wastes * time. */ if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) { if ((pkey = X509_get_pubkey(xi)) == NULL) { ctx->error = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY; ctx->current_cert = xi; ok = (*cb) (0, ctx); if (!ok) goto end; } else if (X509_verify(xs, pkey) <= 0) { ctx->error = X509_V_ERR_CERT_SIGNATURE_FAILURE; ctx->current_cert = xs; ok = (*cb) (0, ctx); if (!ok) { EVP_PKEY_free(pkey); goto end; } } EVP_PKEY_free(pkey); pkey = NULL; } check_cert: ok = check_cert_time(ctx, xs); if (!ok) goto end; /* The last error (if any) is still in the error value */ ctx->current_issuer = xi; ctx->current_cert = xs; ok = (*cb) (1, ctx); if (!ok) goto end; n--; if (n >= 0) { xi = xs; xs = sk_X509_value(ctx->chain, n); } } ok = 1; end: return ok; } int X509_cmp_current_time(const ASN1_TIME *ctm) { return X509_cmp_time(ctm, NULL); } int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time) { static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1; static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1; ASN1_TIME *asn1_cmp_time = NULL; int i, day, sec, ret = 0; /* * Note that ASN.1 allows much more slack in the time format than RFC 5280. * In RFC 5280, the representation is fixed: * UTCTime: YYMMDDHHMMSSZ * GeneralizedTime: YYYYMMDDHHMMSSZ * * We do NOT currently enforce the following RFC 5280 requirement: * "CAs conforming to this profile MUST always encode certificate * validity dates through the year 2049 as UTCTime; certificate validity * dates in 2050 or later MUST be encoded as GeneralizedTime." */ switch (ctm->type) { case V_ASN1_UTCTIME: if (ctm->length != (int)(utctime_length)) return 0; break; case V_ASN1_GENERALIZEDTIME: if (ctm->length != (int)(generalizedtime_length)) return 0; break; default: return 0; } /** * Verify the format: the ASN.1 functions we use below allow a more * flexible format than what's mandated by RFC 5280. * Digit and date ranges will be verified in the conversion methods. */ for (i = 0; i < ctm->length - 1; i++) { if (!isdigit(ctm->data[i])) return 0; } if (ctm->data[ctm->length - 1] != 'Z') return 0; /* * There is ASN1_UTCTIME_cmp_time_t but no * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t, * so we go through ASN.1 */ asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time); if (asn1_cmp_time == NULL) goto err; if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time)) goto err; /* * X509_cmp_time comparison is <=. * The return value 0 is reserved for errors. */ ret = (day >= 0 && sec >= 0) ? -1 : 1; err: ASN1_TIME_free(asn1_cmp_time); return ret; } ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long offset_sec) { return X509_time_adj(s, offset_sec, NULL); } ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm) { return X509_time_adj_ex(s, 0, offset_sec, in_tm); } ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s, int offset_day, long offset_sec, time_t *in_tm) { time_t t = 0; if (in_tm) { t = *in_tm; } else { time(&t); } return ASN1_TIME_adj(s, t, offset_day, offset_sec); } /* Make a delta CRL as the diff between two full CRLs */ X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer, EVP_PKEY *skey, const EVP_MD *md, unsigned int flags) { X509_CRL *crl = NULL; int i; size_t j; STACK_OF(X509_REVOKED) *revs = NULL; /* CRLs can't be delta already */ if (base->base_crl_number || newer->base_crl_number) { OPENSSL_PUT_ERROR(X509, X509_R_CRL_ALREADY_DELTA); return NULL; } /* Base and new CRL must have a CRL number */ if (!base->crl_number || !newer->crl_number) { OPENSSL_PUT_ERROR(X509, X509_R_NO_CRL_NUMBER); return NULL; } /* Issuer names must match */ if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) { OPENSSL_PUT_ERROR(X509, X509_R_ISSUER_MISMATCH); return NULL; } /* AKID and IDP must match */ if (!crl_extension_match(base, newer, NID_authority_key_identifier)) { OPENSSL_PUT_ERROR(X509, X509_R_AKID_MISMATCH); return NULL; } if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) { OPENSSL_PUT_ERROR(X509, X509_R_IDP_MISMATCH); return NULL; } /* Newer CRL number must exceed full CRL number */ if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) { OPENSSL_PUT_ERROR(X509, X509_R_NEWER_CRL_NOT_NEWER); return NULL; } /* CRLs must verify */ if (skey && (X509_CRL_verify(base, skey) <= 0 || X509_CRL_verify(newer, skey) <= 0)) { OPENSSL_PUT_ERROR(X509, X509_R_CRL_VERIFY_FAILURE); return NULL; } /* Create new CRL */ crl = X509_CRL_new(); if (!crl || !X509_CRL_set_version(crl, X509_CRL_VERSION_2)) goto memerr; /* Set issuer name */ if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer))) goto memerr; if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer))) goto memerr; if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer))) goto memerr; /* Set base CRL number: must be critical */ if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0)) goto memerr; /* * Copy extensions across from newest CRL to delta: this will set CRL * number to correct value too. */ for (i = 0; i < X509_CRL_get_ext_count(newer); i++) { X509_EXTENSION *ext; ext = X509_CRL_get_ext(newer, i); if (!X509_CRL_add_ext(crl, ext, -1)) goto memerr; } /* Go through revoked entries, copying as needed */ revs = X509_CRL_get_REVOKED(newer); for (j = 0; j < sk_X509_REVOKED_num(revs); j++) { X509_REVOKED *rvn, *rvtmp; rvn = sk_X509_REVOKED_value(revs, j); /* * 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)) { rvtmp = X509_REVOKED_dup(rvn); if (!rvtmp) goto memerr; if (!X509_CRL_add0_revoked(crl, rvtmp)) { X509_REVOKED_free(rvtmp); goto memerr; } } } /* TODO: optionally prune deleted entries */ if (skey && md && !X509_CRL_sign(crl, skey, md)) goto memerr; return crl; memerr: OPENSSL_PUT_ERROR(X509, ERR_R_MALLOC_FAILURE); if (crl) X509_CRL_free(crl); return NULL; } int X509_STORE_CTX_get_ex_new_index(long argl, void *argp, CRYPTO_EX_unused * unused, CRYPTO_EX_dup *dup_unused, 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). */ int index; if (!CRYPTO_get_ex_new_index(&g_ex_data_class, &index, argl, argp, free_func)) { return -1; } return index; } 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 *ctx) { return ctx->chain; } STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx) { if (!ctx->chain) return NULL; return X509_chain_up_ref(ctx->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; } 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; } STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx) { return ctx->untrusted; } 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) { OPENSSL_PUT_ERROR(X509, 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) { OPENSSL_PUT_ERROR(X509, 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) { OPENSSL_PUT_ERROR(X509, X509_R_UNKNOWN_TRUST_ID); return 0; } } if (purpose && !ctx->param->purpose) ctx->param->purpose = purpose; if (trust && !ctx->param->trust) ctx->param->trust = trust; return 1; } X509_STORE_CTX *X509_STORE_CTX_new(void) { X509_STORE_CTX *ctx; ctx = (X509_STORE_CTX *)OPENSSL_malloc(sizeof(X509_STORE_CTX)); if (!ctx) { OPENSSL_PUT_ERROR(X509, ERR_R_MALLOC_FAILURE); return NULL; } X509_STORE_CTX_zero(ctx); return ctx; } void X509_STORE_CTX_zero(X509_STORE_CTX *ctx) { OPENSSL_memset(ctx, 0, sizeof(X509_STORE_CTX)); } void X509_STORE_CTX_free(X509_STORE_CTX *ctx) { if (ctx == NULL) { return; } X509_STORE_CTX_cleanup(ctx); OPENSSL_free(ctx); } int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509, STACK_OF(X509) *chain) { X509_STORE_CTX_zero(ctx); ctx->ctx = store; ctx->cert = x509; ctx->untrusted = chain; CRYPTO_new_ex_data(&ctx->ex_data); if (store == NULL) { OPENSSL_PUT_ERROR(X509, ERR_R_PASSED_NULL_PARAMETER); goto err; } ctx->param = X509_VERIFY_PARAM_new(); if (!ctx->param) goto err; /* * Inherit callbacks and flags from X509_STORE. */ ctx->verify_cb = store->verify_cb; ctx->cleanup = store->cleanup; if (!X509_VERIFY_PARAM_inherit(ctx->param, store->param) || !X509_VERIFY_PARAM_inherit(ctx->param, X509_VERIFY_PARAM_lookup("default"))) { goto err; } if (store->check_issued) ctx->check_issued = store->check_issued; else ctx->check_issued = check_issued; if (store->get_issuer) ctx->get_issuer = store->get_issuer; else ctx->get_issuer = X509_STORE_CTX_get1_issuer; if (store->verify_cb) ctx->verify_cb = store->verify_cb; else ctx->verify_cb = null_callback; if (store->verify) ctx->verify = store->verify; else ctx->verify = internal_verify; if (store->check_revocation) ctx->check_revocation = store->check_revocation; else ctx->check_revocation = check_revocation; if (store->get_crl) ctx->get_crl = store->get_crl; else ctx->get_crl = NULL; if (store->check_crl) ctx->check_crl = store->check_crl; else ctx->check_crl = check_crl; if (store->cert_crl) ctx->cert_crl = store->cert_crl; else ctx->cert_crl = cert_crl; if (store->lookup_certs) ctx->lookup_certs = store->lookup_certs; else ctx->lookup_certs = X509_STORE_get1_certs; if (store->lookup_crls) ctx->lookup_crls = store->lookup_crls; else ctx->lookup_crls = X509_STORE_get1_crls; ctx->check_policy = check_policy; return 1; err: CRYPTO_free_ex_data(&g_ex_data_class, ctx, &ctx->ex_data); if (ctx->param != NULL) { X509_VERIFY_PARAM_free(ctx->param); } OPENSSL_memset(ctx, 0, sizeof(X509_STORE_CTX)); OPENSSL_PUT_ERROR(X509, ERR_R_MALLOC_FAILURE); return 0; } /* * Set alternative lookup method: just a STACK of trusted certificates. This * avoids X509_STORE nastiness where it isn't needed. */ void X509_STORE_CTX_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk) { ctx->other_ctx = sk; ctx->get_issuer = get_issuer_sk; } void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx) { /* We need to be idempotent because, unfortunately, |X509_STORE_CTX_free| * also calls this function. */ 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; } CRYPTO_free_ex_data(&g_ex_data_class, ctx, &(ctx->ex_data)); OPENSSL_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); } X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx) { return ctx->cert; } void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx, int (*verify_cb) (int, X509_STORE_CTX *)) { ctx->verify_cb = verify_cb; } X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx) { return ctx->tree; } int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx) { return ctx->explicit_policy; } int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name) { const X509_VERIFY_PARAM *param; param = X509_VERIFY_PARAM_lookup(name); if (!param) return 0; return X509_VERIFY_PARAM_inherit(ctx->param, param); } X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx) { return ctx->param; } void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param) { if (ctx->param) X509_VERIFY_PARAM_free(ctx->param); ctx->param = param; }