diff options
Diffstat (limited to 'openssl/crypto/x509v3/v3_purp.c')
| -rw-r--r-- | openssl/crypto/x509v3/v3_purp.c | 767 |
1 files changed, 767 insertions, 0 deletions
diff --git a/openssl/crypto/x509v3/v3_purp.c b/openssl/crypto/x509v3/v3_purp.c new file mode 100644 index 00000000..181bd349 --- /dev/null +++ b/openssl/crypto/x509v3/v3_purp.c @@ -0,0 +1,767 @@ +/* v3_purp.c */ +/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL + * project 2001. + */ +/* ==================================================================== + * Copyright (c) 1999-2004 The OpenSSL Project. All rights reserved. + * + * 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 above 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 acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" + * + * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to + * endorse or promote products derived from this software without + * prior written permission. For written permission, please contact + * licensing@OpenSSL.org. + * + * 5. Products derived from this software may not be called "OpenSSL" + * nor may "OpenSSL" appear in their names without prior written + * permission of the OpenSSL Project. + * + * 6. Redistributions of any form whatsoever must retain the following + * acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" + * + * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY + * EXPRESSED 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 OpenSSL PROJECT OR + * ITS 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. + * ==================================================================== + * + * This product includes cryptographic software written by Eric Young + * (eay@cryptsoft.com). This product includes software written by Tim + * Hudson (tjh@cryptsoft.com). + * + */ + +#include <stdio.h> +#include "cryptlib.h" +#include <openssl/x509v3.h> +#include <openssl/x509_vfy.h> + +static void x509v3_cache_extensions(X509 *x); + +static int check_ssl_ca(const X509 *x); +static int check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x, int ca); +static int check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca); +static int check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca); +static int purpose_smime(const X509 *x, int ca); +static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int ca); +static int check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x, int ca); +static int check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x, int ca); +static int check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x, int ca); +static int no_check(const X509_PURPOSE *xp, const X509 *x, int ca); +static int ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca); + +static int xp_cmp(const X509_PURPOSE * const *a, + const X509_PURPOSE * const *b); +static void xptable_free(X509_PURPOSE *p); + +static X509_PURPOSE xstandard[] = { + {X509_PURPOSE_SSL_CLIENT, X509_TRUST_SSL_CLIENT, 0, check_purpose_ssl_client, "SSL client", "sslclient", NULL}, + {X509_PURPOSE_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ssl_server, "SSL server", "sslserver", NULL}, + {X509_PURPOSE_NS_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ns_ssl_server, "Netscape SSL server", "nssslserver", NULL}, + {X509_PURPOSE_SMIME_SIGN, X509_TRUST_EMAIL, 0, check_purpose_smime_sign, "S/MIME signing", "smimesign", NULL}, + {X509_PURPOSE_SMIME_ENCRYPT, X509_TRUST_EMAIL, 0, check_purpose_smime_encrypt, "S/MIME encryption", "smimeencrypt", NULL}, + {X509_PURPOSE_CRL_SIGN, X509_TRUST_COMPAT, 0, check_purpose_crl_sign, "CRL signing", "crlsign", NULL}, + {X509_PURPOSE_ANY, X509_TRUST_DEFAULT, 0, no_check, "Any Purpose", "any", NULL}, + {X509_PURPOSE_OCSP_HELPER, X509_TRUST_COMPAT, 0, ocsp_helper, "OCSP helper", "ocsphelper", NULL}, + {X509_PURPOSE_TIMESTAMP_SIGN, X509_TRUST_TSA, 0, check_purpose_timestamp_sign, "Time Stamp signing", "timestampsign", NULL}, +}; + +#define X509_PURPOSE_COUNT (sizeof(xstandard)/sizeof(X509_PURPOSE)) + +IMPLEMENT_STACK_OF(X509_PURPOSE) + +static STACK_OF(X509_PURPOSE) *xptable = NULL; + +static int xp_cmp(const X509_PURPOSE * const *a, + const X509_PURPOSE * const *b) +{ + return (*a)->purpose - (*b)->purpose; +} + +/* As much as I'd like to make X509_check_purpose use a "const" X509* + * I really can't because it does recalculate hashes and do other non-const + * things. */ +int X509_check_purpose(X509 *x, int id, int ca) +{ + int idx; + const X509_PURPOSE *pt; + if(!(x->ex_flags & EXFLAG_SET)) { + CRYPTO_w_lock(CRYPTO_LOCK_X509); + x509v3_cache_extensions(x); + CRYPTO_w_unlock(CRYPTO_LOCK_X509); + } + if(id == -1) return 1; + idx = X509_PURPOSE_get_by_id(id); + if(idx == -1) return -1; + pt = X509_PURPOSE_get0(idx); + return pt->check_purpose(pt, x, ca); +} + +int X509_PURPOSE_set(int *p, int purpose) +{ + if(X509_PURPOSE_get_by_id(purpose) == -1) { + X509V3err(X509V3_F_X509_PURPOSE_SET, X509V3_R_INVALID_PURPOSE); + return 0; + } + *p = purpose; + return 1; +} + +int X509_PURPOSE_get_count(void) +{ + if(!xptable) return X509_PURPOSE_COUNT; + return sk_X509_PURPOSE_num(xptable) + X509_PURPOSE_COUNT; +} + +X509_PURPOSE * X509_PURPOSE_get0(int idx) +{ + if(idx < 0) return NULL; + if(idx < (int)X509_PURPOSE_COUNT) return xstandard + idx; + return sk_X509_PURPOSE_value(xptable, idx - X509_PURPOSE_COUNT); +} + +int X509_PURPOSE_get_by_sname(char *sname) +{ + int i; + X509_PURPOSE *xptmp; + for(i = 0; i < X509_PURPOSE_get_count(); i++) { + xptmp = X509_PURPOSE_get0(i); + if(!strcmp(xptmp->sname, sname)) return i; + } + return -1; +} + +int X509_PURPOSE_get_by_id(int purpose) +{ + X509_PURPOSE tmp; + int idx; + if((purpose >= X509_PURPOSE_MIN) && (purpose <= X509_PURPOSE_MAX)) + return purpose - X509_PURPOSE_MIN; + tmp.purpose = purpose; + if(!xptable) return -1; + idx = sk_X509_PURPOSE_find(xptable, &tmp); + if(idx == -1) return -1; + return idx + X509_PURPOSE_COUNT; +} + +int X509_PURPOSE_add(int id, int trust, int flags, + int (*ck)(const X509_PURPOSE *, const X509 *, int), + char *name, char *sname, void *arg) +{ + int idx; + X509_PURPOSE *ptmp; + /* This is set according to what we change: application can't set it */ + flags &= ~X509_PURPOSE_DYNAMIC; + /* This will always be set for application modified trust entries */ + flags |= X509_PURPOSE_DYNAMIC_NAME; + /* Get existing entry if any */ + idx = X509_PURPOSE_get_by_id(id); + /* Need a new entry */ + if(idx == -1) { + if(!(ptmp = OPENSSL_malloc(sizeof(X509_PURPOSE)))) { + X509V3err(X509V3_F_X509_PURPOSE_ADD,ERR_R_MALLOC_FAILURE); + return 0; + } + ptmp->flags = X509_PURPOSE_DYNAMIC; + } else ptmp = X509_PURPOSE_get0(idx); + + /* OPENSSL_free existing name if dynamic */ + if(ptmp->flags & X509_PURPOSE_DYNAMIC_NAME) { + OPENSSL_free(ptmp->name); + OPENSSL_free(ptmp->sname); + } + /* dup supplied name */ + ptmp->name = BUF_strdup(name); + ptmp->sname = BUF_strdup(sname); + if(!ptmp->name || !ptmp->sname) { + X509V3err(X509V3_F_X509_PURPOSE_ADD,ERR_R_MALLOC_FAILURE); + return 0; + } + /* Keep the dynamic flag of existing entry */ + ptmp->flags &= X509_PURPOSE_DYNAMIC; + /* Set all other flags */ + ptmp->flags |= flags; + + ptmp->purpose = id; + ptmp->trust = trust; + ptmp->check_purpose = ck; + ptmp->usr_data = arg; + + /* If its a new entry manage the dynamic table */ + if(idx == -1) { + if(!xptable && !(xptable = sk_X509_PURPOSE_new(xp_cmp))) { + X509V3err(X509V3_F_X509_PURPOSE_ADD,ERR_R_MALLOC_FAILURE); + return 0; + } + if (!sk_X509_PURPOSE_push(xptable, ptmp)) { + X509V3err(X509V3_F_X509_PURPOSE_ADD,ERR_R_MALLOC_FAILURE); + return 0; + } + } + return 1; +} + +static void xptable_free(X509_PURPOSE *p) + { + if(!p) return; + if (p->flags & X509_PURPOSE_DYNAMIC) + { + if (p->flags & X509_PURPOSE_DYNAMIC_NAME) { + OPENSSL_free(p->name); + OPENSSL_free(p->sname); + } + OPENSSL_free(p); + } + } + +void X509_PURPOSE_cleanup(void) +{ + unsigned int i; + sk_X509_PURPOSE_pop_free(xptable, xptable_free); + for(i = 0; i < X509_PURPOSE_COUNT; i++) xptable_free(xstandard + i); + xptable = NULL; +} + +int X509_PURPOSE_get_id(X509_PURPOSE *xp) +{ + return xp->purpose; +} + +char *X509_PURPOSE_get0_name(X509_PURPOSE *xp) +{ + return xp->name; +} + +char *X509_PURPOSE_get0_sname(X509_PURPOSE *xp) +{ + return xp->sname; +} + +int X509_PURPOSE_get_trust(X509_PURPOSE *xp) +{ + return xp->trust; +} + +static int nid_cmp(const int *a, const int *b) + { + return *a - *b; + } + +DECLARE_OBJ_BSEARCH_CMP_FN(int, int, nid); +IMPLEMENT_OBJ_BSEARCH_CMP_FN(int, int, nid); + +int X509_supported_extension(X509_EXTENSION *ex) + { + /* This table is a list of the NIDs of supported extensions: + * that is those which are used by the verify process. If + * an extension is critical and doesn't appear in this list + * then the verify process will normally reject the certificate. + * The list must be kept in numerical order because it will be + * searched using bsearch. + */ + + static const int supported_nids[] = { + NID_netscape_cert_type, /* 71 */ + NID_key_usage, /* 83 */ + NID_subject_alt_name, /* 85 */ + NID_basic_constraints, /* 87 */ + NID_certificate_policies, /* 89 */ + NID_ext_key_usage, /* 126 */ +#ifndef OPENSSL_NO_RFC3779 + NID_sbgp_ipAddrBlock, /* 290 */ + NID_sbgp_autonomousSysNum, /* 291 */ +#endif + NID_policy_constraints, /* 401 */ + NID_proxyCertInfo, /* 663 */ + NID_name_constraints, /* 666 */ + NID_policy_mappings, /* 747 */ + NID_inhibit_any_policy /* 748 */ + }; + + int ex_nid = OBJ_obj2nid(X509_EXTENSION_get_object(ex)); + + if (ex_nid == NID_undef) + return 0; + + if (OBJ_bsearch_nid(&ex_nid, supported_nids, + sizeof(supported_nids)/sizeof(int))) + return 1; + return 0; + } + +static void setup_dp(X509 *x, DIST_POINT *dp) + { + X509_NAME *iname = NULL; + int i; + if (dp->reasons) + { + if (dp->reasons->length > 0) + dp->dp_reasons = dp->reasons->data[0]; + if (dp->reasons->length > 1) + dp->dp_reasons |= (dp->reasons->data[1] << 8); + dp->dp_reasons &= CRLDP_ALL_REASONS; + } + else + dp->dp_reasons = CRLDP_ALL_REASONS; + if (!dp->distpoint || (dp->distpoint->type != 1)) + return; + 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) + { + iname = gen->d.directoryName; + break; + } + } + if (!iname) + iname = X509_get_issuer_name(x); + + DIST_POINT_set_dpname(dp->distpoint, iname); + + } + +static void setup_crldp(X509 *x) + { + int i; + x->crldp = X509_get_ext_d2i(x, NID_crl_distribution_points, NULL, NULL); + for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) + setup_dp(x, sk_DIST_POINT_value(x->crldp, i)); + } + +static void x509v3_cache_extensions(X509 *x) +{ + BASIC_CONSTRAINTS *bs; + PROXY_CERT_INFO_EXTENSION *pci; + ASN1_BIT_STRING *usage; + ASN1_BIT_STRING *ns; + EXTENDED_KEY_USAGE *extusage; + X509_EXTENSION *ex; + + int i; + if(x->ex_flags & EXFLAG_SET) return; +#ifndef OPENSSL_NO_SHA + X509_digest(x, EVP_sha1(), x->sha1_hash, NULL); +#endif + /* Does subject name match issuer ? */ + if(!X509_NAME_cmp(X509_get_subject_name(x), X509_get_issuer_name(x))) + x->ex_flags |= EXFLAG_SI; + /* V1 should mean no extensions ... */ + if(!X509_get_version(x)) x->ex_flags |= EXFLAG_V1; + /* Handle basic constraints */ + if((bs=X509_get_ext_d2i(x, NID_basic_constraints, NULL, NULL))) { + if(bs->ca) x->ex_flags |= EXFLAG_CA; + if(bs->pathlen) { + if((bs->pathlen->type == V_ASN1_NEG_INTEGER) + || !bs->ca) { + x->ex_flags |= EXFLAG_INVALID; + x->ex_pathlen = 0; + } else x->ex_pathlen = ASN1_INTEGER_get(bs->pathlen); + } else x->ex_pathlen = -1; + BASIC_CONSTRAINTS_free(bs); + x->ex_flags |= EXFLAG_BCONS; + } + /* Handle proxy certificates */ + if((pci=X509_get_ext_d2i(x, NID_proxyCertInfo, NULL, NULL))) { + if (x->ex_flags & EXFLAG_CA + || X509_get_ext_by_NID(x, NID_subject_alt_name, 0) >= 0 + || X509_get_ext_by_NID(x, NID_issuer_alt_name, 0) >= 0) { + x->ex_flags |= EXFLAG_INVALID; + } + if (pci->pcPathLengthConstraint) { + x->ex_pcpathlen = + ASN1_INTEGER_get(pci->pcPathLengthConstraint); + } else x->ex_pcpathlen = -1; + PROXY_CERT_INFO_EXTENSION_free(pci); + x->ex_flags |= EXFLAG_PROXY; + } + /* Handle key usage */ + if((usage=X509_get_ext_d2i(x, NID_key_usage, NULL, NULL))) { + if(usage->length > 0) { + x->ex_kusage = usage->data[0]; + if(usage->length > 1) + x->ex_kusage |= usage->data[1] << 8; + } else x->ex_kusage = 0; + x->ex_flags |= EXFLAG_KUSAGE; + ASN1_BIT_STRING_free(usage); + } + x->ex_xkusage = 0; + if((extusage=X509_get_ext_d2i(x, NID_ext_key_usage, NULL, NULL))) { + x->ex_flags |= EXFLAG_XKUSAGE; + for(i = 0; i < sk_ASN1_OBJECT_num(extusage); i++) { + switch(OBJ_obj2nid(sk_ASN1_OBJECT_value(extusage,i))) { + case NID_server_auth: + x->ex_xkusage |= XKU_SSL_SERVER; + break; + + case NID_client_auth: + x->ex_xkusage |= XKU_SSL_CLIENT; + break; + + case NID_email_protect: + x->ex_xkusage |= XKU_SMIME; + break; + + case NID_code_sign: + x->ex_xkusage |= XKU_CODE_SIGN; + break; + + case NID_ms_sgc: + case NID_ns_sgc: + x->ex_xkusage |= XKU_SGC; + break; + + case NID_OCSP_sign: + x->ex_xkusage |= XKU_OCSP_SIGN; + break; + + case NID_time_stamp: + x->ex_xkusage |= XKU_TIMESTAMP; + break; + + case NID_dvcs: + x->ex_xkusage |= XKU_DVCS; + break; + } + } + sk_ASN1_OBJECT_pop_free(extusage, ASN1_OBJECT_free); + } + + if((ns=X509_get_ext_d2i(x, NID_netscape_cert_type, NULL, NULL))) { + if(ns->length > 0) x->ex_nscert = ns->data[0]; + else x->ex_nscert = 0; + x->ex_flags |= EXFLAG_NSCERT; + ASN1_BIT_STRING_free(ns); + } + x->skid =X509_get_ext_d2i(x, NID_subject_key_identifier, NULL, NULL); + x->akid =X509_get_ext_d2i(x, NID_authority_key_identifier, NULL, NULL); + x->altname = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL); + x->nc = X509_get_ext_d2i(x, NID_name_constraints, &i, NULL); + if (!x->nc && (i != -1)) + x->ex_flags |= EXFLAG_INVALID; + setup_crldp(x); + +#ifndef OPENSSL_NO_RFC3779 + x->rfc3779_addr =X509_get_ext_d2i(x, NID_sbgp_ipAddrBlock, NULL, NULL); + x->rfc3779_asid =X509_get_ext_d2i(x, NID_sbgp_autonomousSysNum, + NULL, NULL); +#endif + for (i = 0; i < X509_get_ext_count(x); i++) + { + ex = X509_get_ext(x, i); + if (!X509_EXTENSION_get_critical(ex)) + continue; + if (OBJ_obj2nid(X509_EXTENSION_get_object(ex)) + == NID_freshest_crl) + x->ex_flags |= EXFLAG_FRESHEST; + if (!X509_supported_extension(ex)) + { + x->ex_flags |= EXFLAG_CRITICAL; + break; + } + } + x->ex_flags |= EXFLAG_SET; +} + +/* CA checks common to all purposes + * return codes: + * 0 not a CA + * 1 is a CA + * 2 basicConstraints absent so "maybe" a CA + * 3 basicConstraints absent but self signed V1. + * 4 basicConstraints absent but keyUsage present and keyCertSign asserted. + */ + +#define V1_ROOT (EXFLAG_V1|EXFLAG_SS) +#define ku_reject(x, usage) \ + (((x)->ex_flags & EXFLAG_KUSAGE) && !((x)->ex_kusage & (usage))) +#define xku_reject(x, usage) \ + (((x)->ex_flags & EXFLAG_XKUSAGE) && !((x)->ex_xkusage & (usage))) +#define ns_reject(x, usage) \ + (((x)->ex_flags & EXFLAG_NSCERT) && !((x)->ex_nscert & (usage))) + +static int check_ca(const X509 *x) +{ + /* keyUsage if present should allow cert signing */ + if(ku_reject(x, KU_KEY_CERT_SIGN)) return 0; + if(x->ex_flags & EXFLAG_BCONS) { + if(x->ex_flags & EXFLAG_CA) return 1; + /* If basicConstraints says not a CA then say so */ + else return 0; + } else { + /* we support V1 roots for... uh, I don't really know why. */ + if((x->ex_flags & V1_ROOT) == V1_ROOT) return 3; + /* If key usage present it must have certSign so tolerate it */ + else if (x->ex_flags & EXFLAG_KUSAGE) return 4; + /* Older certificates could have Netscape-specific CA types */ + else if (x->ex_flags & EXFLAG_NSCERT + && x->ex_nscert & NS_ANY_CA) return 5; + /* can this still be regarded a CA certificate? I doubt it */ + return 0; + } +} + +int X509_check_ca(X509 *x) +{ + if(!(x->ex_flags & EXFLAG_SET)) { + CRYPTO_w_lock(CRYPTO_LOCK_X509); + x509v3_cache_extensions(x); + CRYPTO_w_unlock(CRYPTO_LOCK_X509); + } + + return check_ca(x); +} + +/* Check SSL CA: common checks for SSL client and server */ +static int check_ssl_ca(const X509 *x) +{ + int ca_ret; + ca_ret = check_ca(x); + if(!ca_ret) return 0; + /* check nsCertType if present */ + if(ca_ret != 5 || x->ex_nscert & NS_SSL_CA) return ca_ret; + else return 0; +} + + +static int check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + if(xku_reject(x,XKU_SSL_CLIENT)) return 0; + if(ca) return check_ssl_ca(x); + /* We need to do digital signatures with it */ + if(ku_reject(x,KU_DIGITAL_SIGNATURE)) return 0; + /* nsCertType if present should allow SSL client use */ + if(ns_reject(x, NS_SSL_CLIENT)) return 0; + return 1; +} + +static int check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + if(xku_reject(x,XKU_SSL_SERVER|XKU_SGC)) return 0; + if(ca) return check_ssl_ca(x); + + if(ns_reject(x, NS_SSL_SERVER)) return 0; + /* Now as for keyUsage: we'll at least need to sign OR encipher */ + if(ku_reject(x, KU_DIGITAL_SIGNATURE|KU_KEY_ENCIPHERMENT)) return 0; + + return 1; + +} + +static int check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + int ret; + ret = check_purpose_ssl_server(xp, x, ca); + if(!ret || ca) return ret; + /* We need to encipher or Netscape complains */ + if(ku_reject(x, KU_KEY_ENCIPHERMENT)) return 0; + return ret; +} + +/* common S/MIME checks */ +static int purpose_smime(const X509 *x, int ca) +{ + if(xku_reject(x,XKU_SMIME)) return 0; + if(ca) { + int ca_ret; + ca_ret = check_ca(x); + if(!ca_ret) return 0; + /* check nsCertType if present */ + if(ca_ret != 5 || x->ex_nscert & NS_SMIME_CA) return ca_ret; + else return 0; + } + if(x->ex_flags & EXFLAG_NSCERT) { + if(x->ex_nscert & NS_SMIME) return 1; + /* Workaround for some buggy certificates */ + if(x->ex_nscert & NS_SSL_CLIENT) return 2; + return 0; + } + return 1; +} + +static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + int ret; + ret = purpose_smime(x, ca); + if(!ret || ca) return ret; + if(ku_reject(x, KU_DIGITAL_SIGNATURE|KU_NON_REPUDIATION)) return 0; + return ret; +} + +static int check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + int ret; + ret = purpose_smime(x, ca); + if(!ret || ca) return ret; + if(ku_reject(x, KU_KEY_ENCIPHERMENT)) return 0; + return ret; +} + +static int check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + if(ca) { + int ca_ret; + if((ca_ret = check_ca(x)) != 2) return ca_ret; + else return 0; + } + if(ku_reject(x, KU_CRL_SIGN)) return 0; + return 1; +} + +/* OCSP helper: this is *not* a full OCSP check. It just checks that + * each CA is valid. Additional checks must be made on the chain. + */ + +static int ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + /* Must be a valid CA. Should we really support the "I don't know" + value (2)? */ + if(ca) return check_ca(x); + /* leaf certificate is checked in OCSP_verify() */ + return 1; +} + +static int check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x, + int ca) +{ + int i_ext; + + /* If ca is true we must return if this is a valid CA certificate. */ + if (ca) return check_ca(x); + + /* + * Check the optional key usage field: + * if Key Usage is present, it must be one of digitalSignature + * and/or nonRepudiation (other values are not consistent and shall + * be rejected). + */ + if ((x->ex_flags & EXFLAG_KUSAGE) + && ((x->ex_kusage & ~(KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE)) || + !(x->ex_kusage & (KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE)))) + return 0; + + /* Only time stamp key usage is permitted and it's required. */ + if (!(x->ex_flags & EXFLAG_XKUSAGE) || x->ex_xkusage != XKU_TIMESTAMP) + return 0; + + /* Extended Key Usage MUST be critical */ + i_ext = X509_get_ext_by_NID((X509 *) x, NID_ext_key_usage, 0); + if (i_ext >= 0) + { + X509_EXTENSION *ext = X509_get_ext((X509 *) x, i_ext); + if (!X509_EXTENSION_get_critical(ext)) + return 0; + } + + return 1; +} + +static int no_check(const X509_PURPOSE *xp, const X509 *x, int ca) +{ + return 1; +} + +/* Various checks to see if one certificate issued the second. + * This can be used to prune a set of possible issuer certificates + * which have been looked up using some simple method such as by + * subject name. + * These are: + * 1. Check issuer_name(subject) == subject_name(issuer) + * 2. If akid(subject) exists check it matches issuer + * 3. If key_usage(issuer) exists check it supports certificate signing + * returns 0 for OK, positive for reason for mismatch, reasons match + * codes for X509_verify_cert() + */ + +int X509_check_issued(X509 *issuer, X509 *subject) +{ + if(X509_NAME_cmp(X509_get_subject_name(issuer), + X509_get_issuer_name(subject))) + return X509_V_ERR_SUBJECT_ISSUER_MISMATCH; + x509v3_cache_extensions(issuer); + x509v3_cache_extensions(subject); + + if(subject->akid) + { + int ret = X509_check_akid(issuer, subject->akid); + if (ret != X509_V_OK) + return ret; + } + + if(subject->ex_flags & EXFLAG_PROXY) + { + if(ku_reject(issuer, KU_DIGITAL_SIGNATURE)) + return X509_V_ERR_KEYUSAGE_NO_DIGITAL_SIGNATURE; + } + else if(ku_reject(issuer, KU_KEY_CERT_SIGN)) + return X509_V_ERR_KEYUSAGE_NO_CERTSIGN; + return X509_V_OK; +} + +int X509_check_akid(X509 *issuer, AUTHORITY_KEYID *akid) + { + + if(!akid) + return X509_V_OK; + + /* Check key ids (if present) */ + if(akid->keyid && issuer->skid && + ASN1_OCTET_STRING_cmp(akid->keyid, issuer->skid) ) + return X509_V_ERR_AKID_SKID_MISMATCH; + /* Check serial number */ + if(akid->serial && + ASN1_INTEGER_cmp(X509_get_serialNumber(issuer), akid->serial)) + return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH; + /* Check issuer name */ + if(akid->issuer) + { + /* Ugh, for some peculiar reason AKID includes + * SEQUENCE OF GeneralName. So look for a DirName. + * There may be more than one but we only take any + * notice of the first. + */ + GENERAL_NAMES *gens; + GENERAL_NAME *gen; + X509_NAME *nm = NULL; + int i; + gens = akid->issuer; + for(i = 0; i < sk_GENERAL_NAME_num(gens); i++) + { + gen = sk_GENERAL_NAME_value(gens, i); + if(gen->type == GEN_DIRNAME) + { + nm = gen->d.dirn; + break; + } + } + if(nm && X509_NAME_cmp(nm, X509_get_issuer_name(issuer))) + return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH; + } + return X509_V_OK; + } + |