ref: 7be7d0681f567e97fd37f937c2e5e486d6d74eab
dir: /sys/src/ape/lib/openssl/crypto/ocsp/ocsp_vfy.c/
/* ocsp_vfy.c */ /* Written by Dr Stephen N Henson ([email protected]) for the OpenSSL * project 2000. */ /* ==================================================================== * Copyright (c) 2000-2004 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 * [email protected]. * * 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 * ([email protected]). This product includes software written by Tim * Hudson ([email protected]). * */ #include <openssl/ocsp.h> #include <openssl/err.h> #include <string.h> static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, STACK_OF(X509) *certs, X509_STORE *st, unsigned long flags); static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id); static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, unsigned long flags); static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret); static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid, STACK_OF(OCSP_SINGLERESP) *sresp); static int ocsp_check_delegated(X509 *x, int flags); static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, X509_NAME *nm, STACK_OF(X509) *certs, X509_STORE *st, unsigned long flags); /* Verify a basic response message */ int OCSP_basic_verify(OCSP_BASICRESP *bs, STACK_OF(X509) *certs, X509_STORE *st, unsigned long flags) { X509 *signer, *x; STACK_OF(X509) *chain = NULL; X509_STORE_CTX ctx; int i, ret = 0; ret = ocsp_find_signer(&signer, bs, certs, st, flags); if (!ret) { OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND); goto end; } if ((ret == 2) && (flags & OCSP_TRUSTOTHER)) flags |= OCSP_NOVERIFY; if (!(flags & OCSP_NOSIGS)) { EVP_PKEY *skey; skey = X509_get_pubkey(signer); ret = OCSP_BASICRESP_verify(bs, skey, 0); EVP_PKEY_free(skey); if(ret <= 0) { OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNATURE_FAILURE); goto end; } } if (!(flags & OCSP_NOVERIFY)) { int init_res; if(flags & OCSP_NOCHAIN) init_res = X509_STORE_CTX_init(&ctx, st, signer, NULL); else init_res = X509_STORE_CTX_init(&ctx, st, signer, bs->certs); if(!init_res) { OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,ERR_R_X509_LIB); goto end; } X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER); ret = X509_verify_cert(&ctx); chain = X509_STORE_CTX_get1_chain(&ctx); X509_STORE_CTX_cleanup(&ctx); if (ret <= 0) { i = X509_STORE_CTX_get_error(&ctx); OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,OCSP_R_CERTIFICATE_VERIFY_ERROR); ERR_add_error_data(2, "Verify error:", X509_verify_cert_error_string(i)); goto end; } if(flags & OCSP_NOCHECKS) { ret = 1; goto end; } /* At this point we have a valid certificate chain * need to verify it against the OCSP issuer criteria. */ ret = ocsp_check_issuer(bs, chain, flags); /* If fatal error or valid match then finish */ if (ret != 0) goto end; /* Easy case: explicitly trusted. Get root CA and * check for explicit trust */ if(flags & OCSP_NOEXPLICIT) goto end; x = sk_X509_value(chain, sk_X509_num(chain) - 1); if(X509_check_trust(x, NID_OCSP_sign, 0) != X509_TRUST_TRUSTED) { OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,OCSP_R_ROOT_CA_NOT_TRUSTED); goto end; } ret = 1; } end: if(chain) sk_X509_pop_free(chain, X509_free); return ret; } static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, STACK_OF(X509) *certs, X509_STORE *st, unsigned long flags) { X509 *signer; OCSP_RESPID *rid = bs->tbsResponseData->responderId; if ((signer = ocsp_find_signer_sk(certs, rid))) { *psigner = signer; return 2; } if(!(flags & OCSP_NOINTERN) && (signer = ocsp_find_signer_sk(bs->certs, rid))) { *psigner = signer; return 1; } /* Maybe lookup from store if by subject name */ *psigner = NULL; return 0; } static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id) { int i; unsigned char tmphash[SHA_DIGEST_LENGTH], *keyhash; X509 *x; /* Easy if lookup by name */ if (id->type == V_OCSP_RESPID_NAME) return X509_find_by_subject(certs, id->value.byName); /* Lookup by key hash */ /* If key hash isn't SHA1 length then forget it */ if (id->value.byKey->length != SHA_DIGEST_LENGTH) return NULL; keyhash = id->value.byKey->data; /* Calculate hash of each key and compare */ for (i = 0; i < sk_X509_num(certs); i++) { x = sk_X509_value(certs, i); X509_pubkey_digest(x, EVP_sha1(), tmphash, NULL); if(!memcmp(keyhash, tmphash, SHA_DIGEST_LENGTH)) return x; } return NULL; } static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, unsigned long flags) { STACK_OF(OCSP_SINGLERESP) *sresp; X509 *signer, *sca; OCSP_CERTID *caid = NULL; int i; sresp = bs->tbsResponseData->responses; if (sk_X509_num(chain) <= 0) { OCSPerr(OCSP_F_OCSP_CHECK_ISSUER, OCSP_R_NO_CERTIFICATES_IN_CHAIN); return -1; } /* See if the issuer IDs match. */ i = ocsp_check_ids(sresp, &caid); /* If ID mismatch or other error then return */ if (i <= 0) return i; signer = sk_X509_value(chain, 0); /* Check to see if OCSP responder CA matches request CA */ if (sk_X509_num(chain) > 1) { sca = sk_X509_value(chain, 1); i = ocsp_match_issuerid(sca, caid, sresp); if (i < 0) return i; if (i) { /* We have a match, if extensions OK then success */ if (ocsp_check_delegated(signer, flags)) return 1; return 0; } } /* Otherwise check if OCSP request signed directly by request CA */ return ocsp_match_issuerid(signer, caid, sresp); } /* Check the issuer certificate IDs for equality. If there is a mismatch with the same * algorithm then there's no point trying to match any certificates against the issuer. * If the issuer IDs all match then we just need to check equality against one of them. */ static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret) { OCSP_CERTID *tmpid, *cid; int i, idcount; idcount = sk_OCSP_SINGLERESP_num(sresp); if (idcount <= 0) { OCSPerr(OCSP_F_OCSP_CHECK_IDS, OCSP_R_RESPONSE_CONTAINS_NO_REVOCATION_DATA); return -1; } cid = sk_OCSP_SINGLERESP_value(sresp, 0)->certId; *ret = NULL; for (i = 1; i < idcount; i++) { tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId; /* Check to see if IDs match */ if (OCSP_id_issuer_cmp(cid, tmpid)) { /* If algoritm mismatch let caller deal with it */ if (OBJ_cmp(tmpid->hashAlgorithm->algorithm, cid->hashAlgorithm->algorithm)) return 2; /* Else mismatch */ return 0; } } /* All IDs match: only need to check one ID */ *ret = cid; return 1; } static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid, STACK_OF(OCSP_SINGLERESP) *sresp) { /* If only one ID to match then do it */ if(cid) { const EVP_MD *dgst; X509_NAME *iname; int mdlen; unsigned char md[EVP_MAX_MD_SIZE]; if (!(dgst = EVP_get_digestbyobj(cid->hashAlgorithm->algorithm))) { OCSPerr(OCSP_F_OCSP_MATCH_ISSUERID, OCSP_R_UNKNOWN_MESSAGE_DIGEST); return -1; } mdlen = EVP_MD_size(dgst); if ((cid->issuerNameHash->length != mdlen) || (cid->issuerKeyHash->length != mdlen)) return 0; iname = X509_get_subject_name(cert); if (!X509_NAME_digest(iname, dgst, md, NULL)) return -1; if (memcmp(md, cid->issuerNameHash->data, mdlen)) return 0; X509_pubkey_digest(cert, EVP_sha1(), md, NULL); if (memcmp(md, cid->issuerKeyHash->data, mdlen)) return 0; return 1; } else { /* We have to match the whole lot */ int i, ret; OCSP_CERTID *tmpid; for (i = 0; i < sk_OCSP_SINGLERESP_num(sresp); i++) { tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId; ret = ocsp_match_issuerid(cert, tmpid, NULL); if (ret <= 0) return ret; } return 1; } } static int ocsp_check_delegated(X509 *x, int flags) { X509_check_purpose(x, -1, 0); if ((x->ex_flags & EXFLAG_XKUSAGE) && (x->ex_xkusage & XKU_OCSP_SIGN)) return 1; OCSPerr(OCSP_F_OCSP_CHECK_DELEGATED, OCSP_R_MISSING_OCSPSIGNING_USAGE); return 0; } /* Verify an OCSP request. This is fortunately much easier than OCSP * response verify. Just find the signers certificate and verify it * against a given trust value. */ int OCSP_request_verify(OCSP_REQUEST *req, STACK_OF(X509) *certs, X509_STORE *store, unsigned long flags) { X509 *signer; X509_NAME *nm; GENERAL_NAME *gen; int ret; X509_STORE_CTX ctx; if (!req->optionalSignature) { OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_REQUEST_NOT_SIGNED); return 0; } gen = req->tbsRequest->requestorName; if (!gen || gen->type != GEN_DIRNAME) { OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_UNSUPPORTED_REQUESTORNAME_TYPE); return 0; } nm = gen->d.directoryName; ret = ocsp_req_find_signer(&signer, req, nm, certs, store, flags); if (ret <= 0) { OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND); return 0; } if ((ret == 2) && (flags & OCSP_TRUSTOTHER)) flags |= OCSP_NOVERIFY; if (!(flags & OCSP_NOSIGS)) { EVP_PKEY *skey; skey = X509_get_pubkey(signer); ret = OCSP_REQUEST_verify(req, skey); EVP_PKEY_free(skey); if(ret <= 0) { OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_SIGNATURE_FAILURE); return 0; } } if (!(flags & OCSP_NOVERIFY)) { int init_res; if(flags & OCSP_NOCHAIN) init_res = X509_STORE_CTX_init(&ctx, store, signer, NULL); else init_res = X509_STORE_CTX_init(&ctx, store, signer, req->optionalSignature->certs); if(!init_res) { OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY,ERR_R_X509_LIB); return 0; } X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER); X509_STORE_CTX_set_trust(&ctx, X509_TRUST_OCSP_REQUEST); ret = X509_verify_cert(&ctx); X509_STORE_CTX_cleanup(&ctx); if (ret <= 0) { ret = X509_STORE_CTX_get_error(&ctx); OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY,OCSP_R_CERTIFICATE_VERIFY_ERROR); ERR_add_error_data(2, "Verify error:", X509_verify_cert_error_string(ret)); return 0; } } return 1; } static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, X509_NAME *nm, STACK_OF(X509) *certs, X509_STORE *st, unsigned long flags) { X509 *signer; if(!(flags & OCSP_NOINTERN)) { signer = X509_find_by_subject(req->optionalSignature->certs, nm); *psigner = signer; return 1; } signer = X509_find_by_subject(certs, nm); if (signer) { *psigner = signer; return 2; } return 0; }