| /* |
| * Copyright 2001-2016 The OpenSSL Project Authors. All Rights Reserved. |
| * |
| * Licensed under the OpenSSL license (the "License"). You may not use |
| * this file except in compliance with the License. You can obtain a copy |
| * in the file LICENSE in the source distribution or at |
| * https://www.openssl.org/source/license.html |
| */ |
| |
| #include <openssl/ocsp.h> |
| #include "ocsp_local.h" |
| #include <openssl/err.h> |
| #include <string.h> |
| |
| static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, |
| STACK_OF(X509) *certs, 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); |
| 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); |
| static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, |
| X509_NAME *nm, STACK_OF(X509) *certs, |
| 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; |
| STACK_OF(X509) *untrusted = NULL; |
| X509_STORE_CTX *ctx = NULL; |
| int i, ret = ocsp_find_signer(&signer, bs, certs, flags); |
| |
| if (!ret) { |
| OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, |
| OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND); |
| goto end; |
| } |
| ctx = X509_STORE_CTX_new(); |
| if (ctx == NULL) { |
| OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, ERR_R_MALLOC_FAILURE); |
| goto f_err; |
| } |
| if ((ret == 2) && (flags & OCSP_TRUSTOTHER)) |
| flags |= OCSP_NOVERIFY; |
| if (!(flags & OCSP_NOSIGS)) { |
| EVP_PKEY *skey; |
| skey = X509_get0_pubkey(signer); |
| if (skey == NULL) { |
| OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_NO_SIGNER_KEY); |
| goto err; |
| } |
| ret = OCSP_BASICRESP_verify(bs, skey, 0); |
| 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) { |
| untrusted = NULL; |
| } else if (bs->certs && certs) { |
| untrusted = sk_X509_dup(bs->certs); |
| for (i = 0; i < sk_X509_num(certs); i++) { |
| if (!sk_X509_push(untrusted, sk_X509_value(certs, i))) { |
| OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, ERR_R_MALLOC_FAILURE); |
| goto f_err; |
| } |
| } |
| } else if (certs != NULL) { |
| untrusted = certs; |
| } else { |
| untrusted = bs->certs; |
| } |
| init_res = X509_STORE_CTX_init(ctx, st, signer, untrusted); |
| if (!init_res) { |
| OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, ERR_R_X509_LIB); |
| goto f_err; |
| } |
| |
| X509_STORE_CTX_set_purpose(ctx, X509_PURPOSE_OCSP_HELPER); |
| ret = X509_verify_cert(ctx); |
| chain = X509_STORE_CTX_get1_chain(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); |
| |
| /* 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 err; |
| } |
| ret = 1; |
| } |
| end: |
| X509_STORE_CTX_free(ctx); |
| sk_X509_pop_free(chain, X509_free); |
| if (bs->certs && certs) |
| sk_X509_free(untrusted); |
| return ret; |
| |
| err: |
| ret = 0; |
| goto end; |
| f_err: |
| ret = -1; |
| goto end; |
| } |
| |
| int OCSP_resp_get0_signer(OCSP_BASICRESP *bs, X509 **signer, |
| STACK_OF(X509) *extra_certs) |
| { |
| int ret; |
| |
| ret = ocsp_find_signer(signer, bs, extra_certs, 0); |
| return (ret > 0) ? 1 : 0; |
| } |
| |
| static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, |
| STACK_OF(X509) *certs, 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) |
| { |
| 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)) |
| 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 algorithm 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)) |
| == NULL) { |
| OCSPerr(OCSP_F_OCSP_MATCH_ISSUERID, |
| OCSP_R_UNKNOWN_MESSAGE_DIGEST); |
| return -1; |
| } |
| |
| mdlen = EVP_MD_size(dgst); |
| if (mdlen < 0) |
| return -1; |
| 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, dgst, 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) |
| { |
| if ((X509_get_extension_flags(x) & EXFLAG_XKUSAGE) |
| && (X509_get_extended_key_usage(x) & 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 = 0; |
| X509_STORE_CTX *ctx = X509_STORE_CTX_new(); |
| |
| if (ctx == NULL) { |
| OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, ERR_R_MALLOC_FAILURE); |
| goto err; |
| } |
| |
| if (!req->optionalSignature) { |
| OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_REQUEST_NOT_SIGNED); |
| goto err; |
| } |
| gen = req->tbsRequest.requestorName; |
| if (!gen || gen->type != GEN_DIRNAME) { |
| OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, |
| OCSP_R_UNSUPPORTED_REQUESTORNAME_TYPE); |
| goto err; |
| } |
| nm = gen->d.directoryName; |
| ret = ocsp_req_find_signer(&signer, req, nm, certs, flags); |
| if (ret <= 0) { |
| OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, |
| OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND); |
| goto err; |
| } |
| if ((ret == 2) && (flags & OCSP_TRUSTOTHER)) |
| flags |= OCSP_NOVERIFY; |
| if (!(flags & OCSP_NOSIGS)) { |
| EVP_PKEY *skey; |
| skey = X509_get0_pubkey(signer); |
| ret = OCSP_REQUEST_verify(req, skey); |
| if (ret <= 0) { |
| OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_SIGNATURE_FAILURE); |
| goto err; |
| } |
| } |
| 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); |
| goto err; |
| } |
| |
| 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); |
| 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)); |
| goto err; |
| } |
| } |
| ret = 1; |
| goto end; |
| |
| err: |
| ret = 0; |
| end: |
| X509_STORE_CTX_free(ctx); |
| return ret; |
| |
| } |
| |
| static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, |
| X509_NAME *nm, STACK_OF(X509) *certs, |
| unsigned long flags) |
| { |
| X509 *signer; |
| if (!(flags & OCSP_NOINTERN)) { |
| signer = X509_find_by_subject(req->optionalSignature->certs, nm); |
| if (signer) { |
| *psigner = signer; |
| return 1; |
| } |
| } |
| |
| signer = X509_find_by_subject(certs, nm); |
| if (signer) { |
| *psigner = signer; |
| return 2; |
| } |
| return 0; |
| } |
