ssl_util_ssl.c revision d58a822aff1dfda25384d3d009f88f1883c95436
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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
*
* http://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.
*/
/* _ _
* _ __ ___ ___ __| | ___ ___| | mod_ssl
* | '_ ` _ \ / _ \ / _` | / __/ __| | Apache Interface to OpenSSL
* | | | | | | (_) | (_| | \__ \__ \ |
* |_| |_| |_|\___/ \__,_|___|___/___/_|
* |_____|
* ssl_util_ssl.c
* Additional Utility Functions for OpenSSL
*/
#include "ssl_private.h"
/* _________________________________________________________________
**
** Additional High-Level Functions for OpenSSL
** _________________________________________________________________
*/
/* we initialize this index at startup time
* and never write to it at request time,
* so this static is thread safe.
* also note that OpenSSL increments at static variable when
* SSL_get_ex_new_index() is called, so we _must_ do this at startup.
*/
static int SSL_app_data2_idx = -1;
void SSL_init_app_data2_idx(void)
{
int i;
if (SSL_app_data2_idx > -1) {
return;
}
/* we _do_ need to call this twice */
for (i=0; i<=1; i++) {
SSL_app_data2_idx =
SSL_get_ex_new_index(0,
"Second Application Data for SSL",
NULL, NULL, NULL);
}
}
void *SSL_get_app_data2(SSL *ssl)
{
return (void *)SSL_get_ex_data(ssl, SSL_app_data2_idx);
}
void SSL_set_app_data2(SSL *ssl, void *arg)
{
SSL_set_ex_data(ssl, SSL_app_data2_idx, (char *)arg);
return;
}
/* _________________________________________________________________
**
** High-Level Certificate / Private Key Loading
** _________________________________________________________________
*/
X509 *SSL_read_X509(char* filename, X509 **x509, pem_password_cb *cb)
{
X509 *rc;
BIO *bioS;
BIO *bioF;
/* 1. try PEM (= DER+Base64+headers) */
if ((bioS=BIO_new_file(filename, "r")) == NULL)
return NULL;
rc = PEM_read_bio_X509 (bioS, x509, cb, NULL);
BIO_free(bioS);
if (rc == NULL) {
/* 2. try DER+Base64 */
if ((bioS=BIO_new_file(filename, "r")) == NULL)
return NULL;
if ((bioF = BIO_new(BIO_f_base64())) == NULL) {
BIO_free(bioS);
return NULL;
}
bioS = BIO_push(bioF, bioS);
rc = d2i_X509_bio(bioS, NULL);
BIO_free_all(bioS);
if (rc == NULL) {
/* 3. try plain DER */
if ((bioS=BIO_new_file(filename, "r")) == NULL)
return NULL;
rc = d2i_X509_bio(bioS, NULL);
BIO_free(bioS);
}
}
if (rc != NULL && x509 != NULL) {
if (*x509 != NULL)
X509_free(*x509);
*x509 = rc;
}
return rc;
}
EVP_PKEY *SSL_read_PrivateKey(char* filename, EVP_PKEY **key, pem_password_cb *cb, void *s)
{
EVP_PKEY *rc;
BIO *bioS;
BIO *bioF;
/* 1. try PEM (= DER+Base64+headers) */
if ((bioS=BIO_new_file(filename, "r")) == NULL)
return NULL;
rc = PEM_read_bio_PrivateKey(bioS, key, cb, s);
BIO_free(bioS);
if (rc == NULL) {
/* 2. try DER+Base64 */
if ((bioS = BIO_new_file(filename, "r")) == NULL)
return NULL;
if ((bioF = BIO_new(BIO_f_base64())) == NULL) {
BIO_free(bioS);
return NULL;
}
bioS = BIO_push(bioF, bioS);
rc = d2i_PrivateKey_bio(bioS, NULL);
BIO_free_all(bioS);
if (rc == NULL) {
/* 3. try plain DER */
if ((bioS = BIO_new_file(filename, "r")) == NULL)
return NULL;
rc = d2i_PrivateKey_bio(bioS, NULL);
BIO_free(bioS);
}
}
if (rc != NULL && key != NULL) {
if (*key != NULL)
EVP_PKEY_free(*key);
*key = rc;
}
return rc;
}
/* _________________________________________________________________
**
** Smart shutdown
** _________________________________________________________________
*/
int SSL_smart_shutdown(SSL *ssl)
{
int i;
int rc;
/*
* Repeat the calls, because SSL_shutdown internally dispatches through a
* little state machine. Usually only one or two interation should be
* needed, so we restrict the total number of restrictions in order to
* avoid process hangs in case the client played bad with the socket
* connection and OpenSSL cannot recognize it.
*/
rc = 0;
for (i = 0; i < 4 /* max 2x pending + 2x data = 4 */; i++) {
if ((rc = SSL_shutdown(ssl)))
break;
}
return rc;
}
/* _________________________________________________________________
**
** Certificate Checks
** _________________________________________________________________
*/
/* check whether cert contains extended key usage with a SGC tag */
BOOL SSL_X509_isSGC(X509 *cert)
{
int ext_nid;
EXTENDED_KEY_USAGE *sk;
BOOL is_sgc;
int i;
is_sgc = FALSE;
sk = X509_get_ext_d2i(cert, NID_ext_key_usage, NULL, NULL);
if (sk) {
for (i = 0; i < sk_ASN1_OBJECT_num(sk); i++) {
ext_nid = OBJ_obj2nid(sk_ASN1_OBJECT_value(sk, i));
if (ext_nid == NID_ms_sgc || ext_nid == NID_ns_sgc) {
is_sgc = TRUE;
break;
}
}
EXTENDED_KEY_USAGE_free(sk);
}
return is_sgc;
}
/* retrieve basic constraints ingredients */
BOOL SSL_X509_getBC(X509 *cert, int *ca, int *pathlen)
{
BASIC_CONSTRAINTS *bc;
BIGNUM *bn = NULL;
char *cp;
bc = X509_get_ext_d2i(cert, NID_basic_constraints, NULL, NULL);
if (bc == NULL)
return FALSE;
*ca = bc->ca;
*pathlen = -1 /* unlimited */;
if (bc->pathlen != NULL) {
if ((bn = ASN1_INTEGER_to_BN(bc->pathlen, NULL)) == NULL)
return FALSE;
if ((cp = BN_bn2dec(bn)) == NULL)
return FALSE;
*pathlen = atoi(cp);
free(cp);
BN_free(bn);
}
BASIC_CONSTRAINTS_free(bc);
return TRUE;
}
/* convert a NAME_ENTRY to UTF8 string */
char *SSL_X509_NAME_ENTRY_to_string(apr_pool_t *p, X509_NAME_ENTRY *xsne)
{
char *result = NULL;
BIO* bio;
int len;
if ((bio = BIO_new(BIO_s_mem())) == NULL)
return NULL;
ASN1_STRING_print_ex(bio, X509_NAME_ENTRY_get_data(xsne),
ASN1_STRFLGS_ESC_CTRL|ASN1_STRFLGS_UTF8_CONVERT);
len = BIO_pending(bio);
result = apr_palloc(p, len+1);
len = BIO_read(bio, result, len);
result[len] = NUL;
BIO_free(bio);
ap_xlate_proto_from_ascii(result, len);
return result;
}
/*
* convert an X509_NAME to an RFC 2253 formatted string, optionally truncated
* to maxlen characters (specify a maxlen of 0 for no length limit)
*/
char *SSL_X509_NAME_to_string(apr_pool_t *p, X509_NAME *dn, int maxlen)
{
char *result = NULL;
BIO *bio;
int len;
if ((bio = BIO_new(BIO_s_mem())) == NULL)
return NULL;
X509_NAME_print_ex(bio, dn, 0, XN_FLAG_RFC2253);
len = BIO_pending(bio);
if (len > 0) {
result = apr_palloc(p, (maxlen > 0) ? maxlen+1 : len+1);
if (maxlen > 0 && maxlen < len) {
len = BIO_read(bio, result, maxlen);
if (maxlen > 2) {
/* insert trailing ellipsis if there's enough space */
apr_snprintf(result + maxlen - 3, 4, "...");
}
} else {
len = BIO_read(bio, result, len);
}
result[len] = NUL;
}
BIO_free(bio);
return result;
}
/* return an array of (RFC 6125 coined) DNS-IDs and CN-IDs in a certificate */
BOOL SSL_X509_getIDs(apr_pool_t *p, X509 *x509, apr_array_header_t **ids)
{
STACK_OF(GENERAL_NAME) *names;
BIO *bio;
X509_NAME *subj;
char **cpp;
int i, n;
if (!x509 || !(*ids = apr_array_make(p, 0, sizeof(char *)))) {
*ids = NULL;
return FALSE;
}
/* First, the DNS-IDs (dNSName entries in the subjectAltName extension) */
if ((names = X509_get_ext_d2i(x509, NID_subject_alt_name, NULL, NULL)) &&
(bio = BIO_new(BIO_s_mem()))) {
GENERAL_NAME *name;
for (i = 0; i < sk_GENERAL_NAME_num(names); i++) {
name = sk_GENERAL_NAME_value(names, i);
if (name->type == GEN_DNS) {
ASN1_STRING_print_ex(bio, name->d.ia5, ASN1_STRFLGS_ESC_CTRL|
ASN1_STRFLGS_UTF8_CONVERT);
n = BIO_pending(bio);
if (n > 0) {
cpp = (char **)apr_array_push(*ids);
*cpp = apr_palloc(p, n+1);
n = BIO_read(bio, *cpp, n);
(*cpp)[n] = NUL;
}
}
}
BIO_free(bio);
}
if (names)
sk_GENERAL_NAME_pop_free(names, GENERAL_NAME_free);
/* Second, the CN-IDs (commonName attributes in the subject DN) */
subj = X509_get_subject_name(x509);
i = -1;
while ((i = X509_NAME_get_index_by_NID(subj, NID_commonName, i)) != -1) {
cpp = (char **)apr_array_push(*ids);
*cpp = SSL_X509_NAME_ENTRY_to_string(p, X509_NAME_get_entry(subj, i));
}
return apr_is_empty_array(*ids) ? FALSE : TRUE;
}
/*
* Check if a certificate matches for a particular name, by iterating over its
* DNS-IDs and CN-IDs (RFC 6125), optionally with basic wildcard matching.
* If server_rec is non-NULL, some (debug/trace) logging is enabled.
*/
BOOL SSL_X509_match_name(apr_pool_t *p, X509 *x509, const char *name,
BOOL allow_wildcard, server_rec *s)
{
BOOL matched = FALSE;
apr_array_header_t *ids;
/*
* At some day in the future, this might be replaced with X509_check_host()
* (available in OpenSSL 1.0.2 and later), but two points should be noted:
* 1) wildcard matching in X509_check_host() might yield different
* results (by default, it supports a broader set of patterns, e.g.
* wildcards in non-initial positions);
* 2) we lose the option of logging each DNS- and CN-ID (until a match
* is found).
*/
if (SSL_X509_getIDs(p, x509, &ids)) {
char *cp;
int i;
char **id = (char **)ids->elts;
BOOL is_wildcard;
for (i = 0; i < ids->nelts; i++) {
if (!id[i])
continue;
/*
* Determine if it is a wildcard ID - we're restrictive
* in the sense that we require the wildcard character to be
* THE left-most label (i.e., the ID must start with "*.")
*/
is_wildcard = (*id[i] == '*' && *(id[i]+1) == '.') ? TRUE : FALSE;
/*
* If the ID includes a wildcard character (and the caller is
* allowing wildcards), check if it matches for the left-most
* DNS label - i.e., the wildcard character is not allowed
* to match a dot. Otherwise, try a simple string compare.
*/
if ((allow_wildcard == TRUE && is_wildcard == TRUE &&
(cp = strchr(name, '.')) && !strcasecmp(id[i]+1, cp)) ||
!strcasecmp(id[i], name)) {
matched = TRUE;
}
if (s) {
ap_log_error(APLOG_MARK, APLOG_TRACE3, 0, s,
"[%s] SSL_X509_match_name: expecting name '%s', "
"%smatched by ID '%s'",
(mySrvConfig(s))->vhost_id, name,
matched == TRUE ? "" : "NOT ", id[i]);
}
if (matched == TRUE) {
break;
}
}
}
if (s) {
ssl_log_xerror(SSLLOG_MARK, APLOG_DEBUG, 0, p, s, x509,
APLOGNO(02412) "[%s] Cert %s for name '%s'",
(mySrvConfig(s))->vhost_id,
matched == TRUE ? "matches" : "does not match",
name);
}
return matched;
}
/* _________________________________________________________________
**
** Low-Level CA Certificate Loading
** _________________________________________________________________
*/
BOOL SSL_X509_INFO_load_file(apr_pool_t *ptemp,
STACK_OF(X509_INFO) *sk,
const char *filename)
{
BIO *in;
if (!(in = BIO_new(BIO_s_file()))) {
return FALSE;
}
if (BIO_read_filename(in, filename) <= 0) {
BIO_free(in);
return FALSE;
}
ERR_clear_error();
PEM_X509_INFO_read_bio(in, sk, NULL, NULL);
BIO_free(in);
return TRUE;
}
BOOL SSL_X509_INFO_load_path(apr_pool_t *ptemp,
STACK_OF(X509_INFO) *sk,
const char *pathname)
{
/* XXX: this dir read code is exactly the same as that in
* ssl_engine_init.c, only the call to handle the fullname is different,
* should fold the duplication.
*/
apr_dir_t *dir;
apr_finfo_t dirent;
apr_int32_t finfo_flags = APR_FINFO_TYPE|APR_FINFO_NAME;
const char *fullname;
BOOL ok = FALSE;
if (apr_dir_open(&dir, pathname, ptemp) != APR_SUCCESS) {
return FALSE;
}
while ((apr_dir_read(&dirent, finfo_flags, dir)) == APR_SUCCESS) {
if (dirent.filetype == APR_DIR) {
continue; /* don't try to load directories */
}
fullname = apr_pstrcat(ptemp,
pathname, "/", dirent.name,
NULL);
if (SSL_X509_INFO_load_file(ptemp, sk, fullname)) {
ok = TRUE;
}
}
apr_dir_close(dir);
return ok;
}
/* _________________________________________________________________
**
** Extra Server Certificate Chain Support
** _________________________________________________________________
*/
/*
* Read a file that optionally contains the server certificate in PEM
* format, possibly followed by a sequence of CA certificates that
* should be sent to the peer in the SSL Certificate message.
*/
int SSL_CTX_use_certificate_chain(
SSL_CTX *ctx, char *file, int skipfirst, pem_password_cb *cb)
{
BIO *bio;
X509 *x509;
unsigned long err;
int n;
if ((bio = BIO_new(BIO_s_file_internal())) == NULL)
return -1;
if (BIO_read_filename(bio, file) <= 0) {
BIO_free(bio);
return -1;
}
/* optionally skip a leading server certificate */
if (skipfirst) {
if ((x509 = PEM_read_bio_X509(bio, NULL, cb, NULL)) == NULL) {
BIO_free(bio);
return -1;
}
X509_free(x509);
}
/* free a perhaps already configured extra chain */
#ifdef OPENSSL_NO_SSL_INTERN
SSL_CTX_clear_extra_chain_certs(ctx);
#else
if (ctx->extra_certs != NULL) {
sk_X509_pop_free((STACK_OF(X509) *)ctx->extra_certs, X509_free);
ctx->extra_certs = NULL;
}
#endif
/* create new extra chain by loading the certs */
n = 0;
while ((x509 = PEM_read_bio_X509(bio, NULL, cb, NULL)) != NULL) {
if (!SSL_CTX_add_extra_chain_cert(ctx, x509)) {
X509_free(x509);
BIO_free(bio);
return -1;
}
n++;
}
/* Make sure that only the error is just an EOF */
if ((err = ERR_peek_error()) > 0) {
if (!( ERR_GET_LIB(err) == ERR_LIB_PEM
&& ERR_GET_REASON(err) == PEM_R_NO_START_LINE)) {
BIO_free(bio);
return -1;
}
while (ERR_get_error() > 0) ;
}
BIO_free(bio);
return n;
}
/* _________________________________________________________________
**
** Session Stuff
** _________________________________________________________________
*/
char *SSL_SESSION_id2sz(unsigned char *id, int idlen,
char *str, int strsize)
{
char *cp;
int n;
cp = str;
for (n = 0; n < idlen && n < SSL_MAX_SSL_SESSION_ID_LENGTH; n++) {
apr_snprintf(cp, strsize - (cp-str), "%02X", id[n]);
cp += 2;
}
*cp = NUL;
return str;
}