blob: f48c128cfdd6284e30f4f307affa8a61d31dd66f [file] [log] [blame] [edit]
// Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// extension creation utilities
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include <openssl/conf.h>
#include <openssl/err.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/x509.h>
#include "../internal.h"
#include "internal.h"
static int v3_check_critical(const char **value);
static int v3_check_generic(const char **value);
static X509_EXTENSION *do_ext_nconf(const CONF *conf, const X509V3_CTX *ctx,
int ext_nid, int crit, const char *value);
static X509_EXTENSION *v3_generic_extension(const char *ext, const char *value,
int crit, int type,
const X509V3_CTX *ctx);
static X509_EXTENSION *do_ext_i2d(const X509V3_EXT_METHOD *method, int ext_nid,
int crit, void *ext_struc);
static unsigned char *generic_asn1(const char *value, const X509V3_CTX *ctx,
size_t *ext_len);
X509_EXTENSION *X509V3_EXT_nconf(const CONF *conf, const X509V3_CTX *ctx,
const char *name, const char *value) {
// If omitted, fill in an empty |X509V3_CTX|.
X509V3_CTX ctx_tmp;
if (ctx == NULL) {
X509V3_set_ctx(&ctx_tmp, NULL, NULL, NULL, NULL, 0);
X509V3_set_nconf(&ctx_tmp, conf);
ctx = &ctx_tmp;
}
int crit = v3_check_critical(&value);
int ext_type = v3_check_generic(&value);
if (ext_type != 0) {
return v3_generic_extension(name, value, crit, ext_type, ctx);
}
X509_EXTENSION *ret = do_ext_nconf(conf, ctx, OBJ_sn2nid(name), crit, value);
if (!ret) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_ERROR_IN_EXTENSION);
ERR_add_error_data(4, "name=", name, ", value=", value);
}
return ret;
}
X509_EXTENSION *X509V3_EXT_nconf_nid(const CONF *conf, const X509V3_CTX *ctx,
int ext_nid, const char *value) {
// If omitted, fill in an empty |X509V3_CTX|.
X509V3_CTX ctx_tmp;
if (ctx == NULL) {
X509V3_set_ctx(&ctx_tmp, NULL, NULL, NULL, NULL, 0);
X509V3_set_nconf(&ctx_tmp, conf);
ctx = &ctx_tmp;
}
int crit = v3_check_critical(&value);
int ext_type = v3_check_generic(&value);
if (ext_type != 0) {
return v3_generic_extension(OBJ_nid2sn(ext_nid), value, crit, ext_type,
ctx);
}
return do_ext_nconf(conf, ctx, ext_nid, crit, value);
}
// CONF *conf: Config file
// char *value: Value
static X509_EXTENSION *do_ext_nconf(const CONF *conf, const X509V3_CTX *ctx,
int ext_nid, int crit, const char *value) {
const X509V3_EXT_METHOD *method;
X509_EXTENSION *ext;
const STACK_OF(CONF_VALUE) *nval;
STACK_OF(CONF_VALUE) *nval_owned = NULL;
void *ext_struc;
if (ext_nid == NID_undef) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_UNKNOWN_EXTENSION_NAME);
return NULL;
}
if (!(method = X509V3_EXT_get_nid(ext_nid))) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_UNKNOWN_EXTENSION);
return NULL;
}
// Now get internal extension representation based on type
if (method->v2i) {
if (*value == '@') {
// TODO(davidben): This is the only place where |X509V3_EXT_nconf|'s
// |conf| parameter is used. All other codepaths use the copy inside
// |ctx|. Should this be switched and then the parameter ignored?
if (conf == NULL) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_NO_CONFIG_DATABASE);
return NULL;
}
nval = NCONF_get_section(conf, value + 1);
} else {
nval_owned = X509V3_parse_list(value);
nval = nval_owned;
}
if (nval == NULL || sk_CONF_VALUE_num(nval) <= 0) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_EXTENSION_STRING);
ERR_add_error_data(4, "name=", OBJ_nid2sn(ext_nid), ",section=", value);
sk_CONF_VALUE_pop_free(nval_owned, X509V3_conf_free);
return NULL;
}
ext_struc = method->v2i(method, ctx, nval);
sk_CONF_VALUE_pop_free(nval_owned, X509V3_conf_free);
if (!ext_struc) {
return NULL;
}
} else if (method->s2i) {
if (!(ext_struc = method->s2i(method, ctx, value))) {
return NULL;
}
} else if (method->r2i) {
// TODO(davidben): Should this check be removed? This matches OpenSSL, but
// r2i-based extensions do not necessarily require a config database. The
// two built-in extensions only use it some of the time, and already handle
// |X509V3_get_section| returning NULL.
if (!ctx->db) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_NO_CONFIG_DATABASE);
return NULL;
}
if (!(ext_struc = method->r2i(method, ctx, value))) {
return NULL;
}
} else {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_EXTENSION_SETTING_NOT_SUPPORTED);
ERR_add_error_data(2, "name=", OBJ_nid2sn(ext_nid));
return NULL;
}
ext = do_ext_i2d(method, ext_nid, crit, ext_struc);
ASN1_item_free(reinterpret_cast<ASN1_VALUE *>(ext_struc),
ASN1_ITEM_ptr(method->it));
return ext;
}
static X509_EXTENSION *do_ext_i2d(const X509V3_EXT_METHOD *method, int ext_nid,
int crit, void *ext_struc) {
// Convert the extension's internal representation to DER.
unsigned char *ext_der = NULL;
int ext_len = ASN1_item_i2d(reinterpret_cast<ASN1_VALUE *>(ext_struc),
&ext_der, ASN1_ITEM_ptr(method->it));
if (ext_len < 0) {
return NULL;
}
ASN1_OCTET_STRING *ext_oct = ASN1_OCTET_STRING_new();
if (ext_oct == NULL) {
OPENSSL_free(ext_der);
return NULL;
}
ASN1_STRING_set0(ext_oct, ext_der, ext_len);
X509_EXTENSION *ext =
X509_EXTENSION_create_by_NID(NULL, ext_nid, crit, ext_oct);
ASN1_OCTET_STRING_free(ext_oct);
return ext;
}
// Given an internal structure, nid and critical flag create an extension
X509_EXTENSION *X509V3_EXT_i2d(int ext_nid, int crit, void *ext_struc) {
const X509V3_EXT_METHOD *method;
if (!(method = X509V3_EXT_get_nid(ext_nid))) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_UNKNOWN_EXTENSION);
return NULL;
}
return do_ext_i2d(method, ext_nid, crit, ext_struc);
}
// Check the extension string for critical flag
static int v3_check_critical(const char **value) {
const char *p = *value;
if ((strlen(p) < 9) || strncmp(p, "critical,", 9)) {
return 0;
}
p += 9;
while (OPENSSL_isspace((unsigned char)*p)) {
p++;
}
*value = p;
return 1;
}
// Check extension string for generic extension and return the type
static int v3_check_generic(const char **value) {
int gen_type = 0;
const char *p = *value;
if ((strlen(p) >= 4) && !strncmp(p, "DER:", 4)) {
p += 4;
gen_type = 1;
} else if ((strlen(p) >= 5) && !strncmp(p, "ASN1:", 5)) {
p += 5;
gen_type = 2;
} else {
return 0;
}
while (OPENSSL_isspace((unsigned char)*p)) {
p++;
}
*value = p;
return gen_type;
}
// Create a generic extension: for now just handle DER type
static X509_EXTENSION *v3_generic_extension(const char *ext, const char *value,
int crit, int gen_type,
const X509V3_CTX *ctx) {
bssl::UniquePtr<ASN1_OBJECT> obj(OBJ_txt2obj(ext, 0));
if (obj == nullptr) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_EXTENSION_NAME_ERROR);
ERR_add_error_data(2, "name=", ext);
return nullptr;
}
bssl::UniquePtr<unsigned char> ext_der;
size_t ext_len = 0;
if (gen_type == 1) {
ext_der.reset(x509v3_hex_to_bytes(value, &ext_len));
} else if (gen_type == 2) {
ext_der.reset(generic_asn1(value, ctx, &ext_len));
}
if (ext_der == nullptr) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_EXTENSION_VALUE_ERROR);
ERR_add_error_data(2, "value=", value);
return nullptr;
}
if (ext_len > INT_MAX) {
OPENSSL_PUT_ERROR(X509V3, ERR_R_OVERFLOW);
return nullptr;
}
bssl::UniquePtr<ASN1_OCTET_STRING> oct(ASN1_OCTET_STRING_new());
if (oct == nullptr) {
return nullptr;
}
ASN1_STRING_set0(oct.get(), ext_der.get(), (int)ext_len);
ext_der.release(); // ASN1_STRING_set0 took ownership.
return X509_EXTENSION_create_by_OBJ(nullptr, obj.get(), crit, oct.get());
}
static unsigned char *generic_asn1(const char *value, const X509V3_CTX *ctx,
size_t *ext_len) {
ASN1_TYPE *typ = ASN1_generate_v3(value, ctx);
if (typ == NULL) {
return NULL;
}
unsigned char *ext_der = NULL;
int len = i2d_ASN1_TYPE(typ, &ext_der);
ASN1_TYPE_free(typ);
if (len < 0) {
return NULL;
}
*ext_len = len;
return ext_der;
}
// This is the main function: add a bunch of extensions based on a config
// file section to an extension STACK.
int X509V3_EXT_add_nconf_sk(const CONF *conf, const X509V3_CTX *ctx,
const char *section,
STACK_OF(X509_EXTENSION) **sk) {
const STACK_OF(CONF_VALUE) *nval = NCONF_get_section(conf, section);
if (nval == NULL) {
return 0;
}
for (size_t i = 0; i < sk_CONF_VALUE_num(nval); i++) {
const CONF_VALUE *val = sk_CONF_VALUE_value(nval, i);
X509_EXTENSION *ext = X509V3_EXT_nconf(conf, ctx, val->name, val->value);
int ok = ext != NULL && //
(sk == NULL || X509v3_add_ext(sk, ext, -1) != NULL);
X509_EXTENSION_free(ext);
if (!ok) {
return 0;
}
}
return 1;
}
// Convenience functions to add extensions to a certificate, CRL and request
int X509V3_EXT_add_nconf(const CONF *conf, const X509V3_CTX *ctx,
const char *section, X509 *cert) {
STACK_OF(X509_EXTENSION) **sk = NULL;
if (cert) {
sk = &cert->cert_info->extensions;
}
return X509V3_EXT_add_nconf_sk(conf, ctx, section, sk);
}
// Same as above but for a CRL
int X509V3_EXT_CRL_add_nconf(const CONF *conf, const X509V3_CTX *ctx,
const char *section, X509_CRL *crl) {
STACK_OF(X509_EXTENSION) **sk = NULL;
if (crl) {
sk = &crl->crl->extensions;
}
return X509V3_EXT_add_nconf_sk(conf, ctx, section, sk);
}
// Add extensions to certificate request
int X509V3_EXT_REQ_add_nconf(const CONF *conf, const X509V3_CTX *ctx,
const char *section, X509_REQ *req) {
STACK_OF(X509_EXTENSION) *extlist = NULL, **sk = NULL;
int i;
if (req) {
sk = &extlist;
}
i = X509V3_EXT_add_nconf_sk(conf, ctx, section, sk);
if (!i || !sk) {
return i;
}
i = X509_REQ_add_extensions(req, extlist);
sk_X509_EXTENSION_pop_free(extlist, X509_EXTENSION_free);
return i;
}
// Config database functions
const STACK_OF(CONF_VALUE) *X509V3_get_section(const X509V3_CTX *ctx,
const char *section) {
if (ctx->db == NULL) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_OPERATION_NOT_DEFINED);
return NULL;
}
return NCONF_get_section(ctx->db, section);
}
void X509V3_set_nconf(X509V3_CTX *ctx, const CONF *conf) { ctx->db = conf; }
void X509V3_set_ctx(X509V3_CTX *ctx, const X509 *issuer, const X509 *subj,
const X509_REQ *req, const X509_CRL *crl, int flags) {
OPENSSL_memset(ctx, 0, sizeof(*ctx));
ctx->issuer_cert = issuer;
ctx->subject_cert = subj;
ctx->crl = crl;
ctx->subject_req = req;
ctx->flags = flags;
}