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apache / httpd / 2c9dfbb7bac6e086b6c72f739a5a5b952f28d6c0 / . / modules / ssl / ssl_engine_kernel.c
blob: 2d628b85298c2a56c000dedef44035fb1ea623ca [file] [log] [blame]
/* _ _
** _ __ ___ ___ __| | ___ ___| | mod_ssl
** | '_ ` _ \ / _ \ / _` | / __/ __| | Apache Interface to OpenSSL
** | | | | | | (_) | (_| | \__ \__ \ | www.modssl.org
** |_| |_| |_|\___/ \__,_|___|___/___/_| ftp.modssl.org
** |_____|
** ssl_engine_kernel.c
** The SSL engine kernel
*/
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000-2003 The Apache Software Foundation. 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. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``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 APACHE SOFTWARE FOUNDATION 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.
* ====================================================================
*/
/* ``It took me fifteen years to discover
I had no talent for programming, but
I couldn't give it up because by that
time I was too famous.''
-- Unknown */
#include "mod_ssl.h"
/*
* Post Read Request Handler
*/
int ssl_hook_ReadReq(request_rec *r)
{
SSLConnRec *sslconn = myConnConfig(r->connection);
SSL *ssl;
if (!sslconn) {
return DECLINED;
}
if (sslconn->non_ssl_request) {
const char *errmsg;
char *thisurl;
char *thisport = "";
int port = ap_get_server_port(r);
if (!ap_is_default_port(port, r)) {
thisport = apr_psprintf(r->pool, ":%u", port);
}
thisurl = ap_escape_html(r->pool,
apr_psprintf(r->pool, "https://%s%s/",
ap_get_server_name(r),
thisport));
errmsg = apr_psprintf(r->pool,
"Reason: You're speaking plain HTTP "
"to an SSL-enabled server port.<br />\n"
"Instead use the HTTPS scheme to access "
"this URL, please.<br />\n"
"<blockquote>Hint: "
"<a href=\"%s\"><b>%s</b></a></blockquote>",
thisurl, thisurl);
apr_table_setn(r->notes, "error-notes", errmsg);
/* Now that we have caught this error, forget it. we are done
* with using SSL on this request.
*/
sslconn->non_ssl_request = 0;
return HTTP_BAD_REQUEST;
}
/*
* Get the SSL connection structure and perform the
* delayed interlinking from SSL back to request_rec
*/
if ((ssl = sslconn->ssl)) {
SSL_set_app_data2(ssl, r);
}
return DECLINED;
}
/*
* Move SetEnvIf information from request_rec to conn_rec/BUFF
* to allow the close connection handler to use them.
*/
static void ssl_configure_env(request_rec *r, SSLConnRec *sslconn)
{
int i;
const apr_array_header_t *arr = apr_table_elts(r->subprocess_env);
const apr_table_entry_t *elts = (const apr_table_entry_t *)arr->elts;
sslconn->shutdown_type = SSL_SHUTDOWN_TYPE_STANDARD;
for (i = 0; i < arr->nelts; i++) {
const char *key = elts[i].key;
switch (*key) {
case 's':
/* being case-sensitive here.
* and not checking for the -shutdown since these are the only
* SetEnvIf "flags" we support
*/
if (!strncmp(key+1, "sl-", 3)) {
key += 4;
if (!strncmp(key, "unclean", 7)) {
sslconn->shutdown_type = SSL_SHUTDOWN_TYPE_UNCLEAN;
}
else if (!strncmp(key, "accurate", 8)) {
sslconn->shutdown_type = SSL_SHUTDOWN_TYPE_ACCURATE;
}
return; /* should only ever be one ssl-*-shutdown */
}
break;
}
}
}
/*
* URL Translation Handler
*/
int ssl_hook_Translate(request_rec *r)
{
SSLConnRec *sslconn = myConnConfig(r->connection);
if (!(sslconn && sslconn->ssl)) {
return DECLINED;
}
/*
* Log information about incoming HTTPS requests
*/
if (r->server->loglevel >= APLOG_INFO && ap_is_initial_req(r)) {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"%s HTTPS request received for child %ld (server %s)",
(r->connection->keepalives <= 0 ?
"Initial (No.1)" :
apr_psprintf(r->pool, "Subsequent (No.%d)",
r->connection->keepalives+1)),
r->connection->id,
ssl_util_vhostid(r->pool, r->server));
}
/* SetEnvIf ssl-*-shutdown flags can only be per-server,
* so they won't change across keepalive requests
*/
if (sslconn->shutdown_type == SSL_SHUTDOWN_TYPE_UNSET) {
ssl_configure_env(r, sslconn);
}
return DECLINED;
}
/*
* Access Handler
*/
int ssl_hook_Access(request_rec *r)
{
SSLDirConfigRec *dc = myDirConfig(r);
SSLSrvConfigRec *sc = mySrvConfig(r->server);
SSLConnRec *sslconn = myConnConfig(r->connection);
SSL *ssl = sslconn ? sslconn->ssl : NULL;
SSL_CTX *ctx = NULL;
apr_array_header_t *requires;
ssl_require_t *ssl_requires;
char *cp;
int ok, i;
BOOL renegotiate = FALSE, renegotiate_quick = FALSE;
X509 *cert;
X509 *peercert;
X509_STORE *cert_store = NULL;
X509_STORE_CTX cert_store_ctx;
STACK_OF(SSL_CIPHER) *cipher_list_old = NULL, *cipher_list = NULL;
SSL_CIPHER *cipher = NULL;
int depth, verify_old, verify, n;
if (ssl) {
ctx = SSL_get_SSL_CTX(ssl);
}
/*
* Support for SSLRequireSSL directive
*/
if (dc->bSSLRequired && !ssl) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
"access to %s failed, reason: %s",
r->filename, "SSL connection required");
/* remember forbidden access for strict require option */
apr_table_setn(r->notes, "ssl-access-forbidden", "1");
return HTTP_FORBIDDEN;
}
/*
* Check to see if SSL protocol is on
*/
if (!(sc->enabled || ssl)) {
return DECLINED;
}
/*
* Support for per-directory reconfigured SSL connection parameters.
*
* This is implemented by forcing an SSL renegotiation with the
* reconfigured parameter suite. But Apache's internal API processing
* makes our life very hard here, because when internal sub-requests occur
* we nevertheless should avoid multiple unnecessary SSL handshakes (they
* require extra network I/O and especially time to perform).
*
* But the optimization for filtering out the unnecessary handshakes isn't
* obvious and trivial. Especially because while Apache is in its
* sub-request processing the client could force additional handshakes,
* too. And these take place perhaps without our notice. So the only
* possibility is to explicitly _ask_ OpenSSL whether the renegotiation
* has to be performed or not. It has to performed when some parameters
* which were previously known (by us) are not those we've now
* reconfigured (as known by OpenSSL) or (in optimized way) at least when
* the reconfigured parameter suite is stronger (more restrictions) than
* the currently active one.
*/
/*
* Override of SSLCipherSuite
*
* We provide two options here:
*
* o The paranoid and default approach where we force a renegotiation when
* the cipher suite changed in _any_ way (which is straight-forward but
* often forces renegotiations too often and is perhaps not what the
* user actually wanted).
*
* o The optimized and still secure way where we force a renegotiation
* only if the currently active cipher is no longer contained in the
* reconfigured/new cipher suite. Any other changes are not important
* because it's the servers choice to select a cipher from the ones the
* client supports. So as long as the current cipher is still in the new
* cipher suite we're happy. Because we can assume we would have
* selected it again even when other (better) ciphers exists now in the
* new cipher suite. This approach is fine because the user explicitly
* has to enable this via ``SSLOptions +OptRenegotiate''. So we do no
* implicit optimizations.
*/
if (dc->szCipherSuite) {
/* remember old state */
if (dc->nOptions & SSL_OPT_OPTRENEGOTIATE) {
cipher = SSL_get_current_cipher(ssl);
}
else {
cipher_list_old = (STACK_OF(SSL_CIPHER) *)SSL_get_ciphers(ssl);
if (cipher_list_old) {
cipher_list_old = sk_SSL_CIPHER_dup(cipher_list_old);
}
}
/* configure new state */
if (!modssl_set_cipher_list(ssl, dc->szCipherSuite)) {
ap_log_error(APLOG_MARK, APLOG_WARNING, 0,
r->server,
"Unable to reconfigure (per-directory) "
"permitted SSL ciphers");
ssl_log_ssl_error(APLOG_MARK, APLOG_ERR, r->server);
if (cipher_list_old) {
sk_SSL_CIPHER_free(cipher_list_old);
}
return HTTP_FORBIDDEN;
}
/* determine whether a renegotiation has to be forced */
cipher_list = (STACK_OF(SSL_CIPHER) *)SSL_get_ciphers(ssl);
if (dc->nOptions & SSL_OPT_OPTRENEGOTIATE) {
/* optimized way */
if ((!cipher && cipher_list) ||
(cipher && !cipher_list))
{
renegotiate = TRUE;
}
else if (cipher && cipher_list &&
(sk_SSL_CIPHER_find(cipher_list, cipher) < 0))
{
renegotiate = TRUE;
}
}
else {
/* paranoid way */
if ((!cipher_list_old && cipher_list) ||
(cipher_list_old && !cipher_list))
{
renegotiate = TRUE;
}
else if (cipher_list_old && cipher_list) {
for (n = 0;
!renegotiate && (n < sk_SSL_CIPHER_num(cipher_list));
n++)
{
SSL_CIPHER *value = sk_SSL_CIPHER_value(cipher_list, n);
if (sk_SSL_CIPHER_find(cipher_list_old, value) < 0) {
renegotiate = TRUE;
}
}
for (n = 0;
!renegotiate && (n < sk_SSL_CIPHER_num(cipher_list_old));
n++)
{
SSL_CIPHER *value = sk_SSL_CIPHER_value(cipher_list_old, n);
if (sk_SSL_CIPHER_find(cipher_list, value) < 0) {
renegotiate = TRUE;
}
}
}
}
/* cleanup */
if (cipher_list_old) {
sk_SSL_CIPHER_free(cipher_list_old);
}
/* tracing */
if (renegotiate) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"Reconfigured cipher suite will force renegotiation");
}
}
/*
* override of SSLVerifyDepth
*
* The depth checks are handled by us manually inside the verify callback
* function and not by OpenSSL internally (and our function is aware of
* both the per-server and per-directory contexts). So we cannot ask
* OpenSSL about the currently verify depth. Instead we remember it in our
* ap_ctx attached to the SSL* of OpenSSL. We've to force the
* renegotiation if the reconfigured/new verify depth is less than the
* currently active/remembered verify depth (because this means more
* restriction on the certificate chain).
*/
if (dc->nVerifyDepth != UNSET) {
/* XXX: doesnt look like sslconn->verify_depth is actually used */
if (!(n = sslconn->verify_depth)) {
sslconn->verify_depth = n = sc->server->auth.verify_depth;
}
/* determine whether a renegotiation has to be forced */
if (dc->nVerifyDepth < n) {
renegotiate = TRUE;
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"Reduced client verification depth will force "
"renegotiation");
}
}
/*
* override of SSLVerifyClient
*
* We force a renegotiation if the reconfigured/new verify type is
* stronger than the currently active verify type.
*
* The order is: none << optional_no_ca << optional << require
*
* Additionally the following optimization is possible here: When the
* currently active verify type is "none" but a client certificate is
* already known/present, it's enough to manually force a client
* verification but at least skip the I/O-intensive renegotation
* handshake.
*/
if (dc->nVerifyClient != SSL_CVERIFY_UNSET) {
/* remember old state */
verify_old = SSL_get_verify_mode(ssl);
/* configure new state */
verify = SSL_VERIFY_NONE;
if (dc->nVerifyClient == SSL_CVERIFY_REQUIRE) {
verify |= SSL_VERIFY_PEER_STRICT;
}
if ((dc->nVerifyClient == SSL_CVERIFY_OPTIONAL) ||
(dc->nVerifyClient == SSL_CVERIFY_OPTIONAL_NO_CA))
{
verify |= SSL_VERIFY_PEER;
}
modssl_set_verify(ssl, verify, ssl_callback_SSLVerify);
SSL_set_verify_result(ssl, X509_V_OK);
/* determine whether we've to force a renegotiation */
if (!renegotiate && verify != verify_old) {
if (((verify_old == SSL_VERIFY_NONE) &&
(verify != SSL_VERIFY_NONE)) ||
(!(verify_old & SSL_VERIFY_PEER) &&
(verify & SSL_VERIFY_PEER)) ||
(!(verify_old & SSL_VERIFY_PEER_STRICT) &&
(verify & SSL_VERIFY_PEER_STRICT)))
{
renegotiate = TRUE;
/* optimization */
if ((dc->nOptions & SSL_OPT_OPTRENEGOTIATE) &&
(verify_old == SSL_VERIFY_NONE) &&
((peercert = SSL_get_peer_certificate(ssl)) != NULL))
{
renegotiate_quick = TRUE;
X509_free(peercert);
}
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0,
r->server,
"Changed client verification type will force "
"%srenegotiation",
renegotiate_quick ? "quick " : "");
}
}
}
/*
* override SSLCACertificateFile & SSLCACertificatePath
* This is only enabled if the SSL_set_cert_store() function
* is available in the ssl library. the 1.x based mod_ssl
* used SSL_CTX_set_cert_store which is not thread safe.
*/
#ifdef HAVE_SSL_SET_CERT_STORE
/*
* check if per-dir and per-server config field are not the same.
* if f is defined in per-dir and not defined in per-server
* or f is defined in both but not the equal ...
*/
#define MODSSL_CFG_NE(f) \
(dc->f && (!sc->f || (sc->f && strNE(dc->f, sc->f))))
#define MODSSL_CFG_CA(f) \
(dc->f ? dc->f : sc->f)
if (MODSSL_CFG_NE(szCACertificateFile) ||
MODSSL_CFG_NE(szCACertificatePath))
{
STACK_OF(X509_NAME) *ca_list;
const char *ca_file = MODSSL_CFG_CA(szCACertificateFile);
const char *ca_path = MODSSL_CFG_CA(szCACertificatePath);
cert_store = X509_STORE_new();
if (!X509_STORE_load_locations(cert_store, ca_file, ca_path)) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Unable to reconfigure verify locations "
"for client authentication");
ssl_log_ssl_error(APLOG_MARK, APLOG_ERR, r->server);
X509_STORE_free(cert_store);
return HTTP_FORBIDDEN;
}
/* SSL_free will free cert_store */
SSL_set_cert_store(ssl, cert_store);
if (!(ca_list = ssl_init_FindCAList(r->server, r->pool,
ca_file, ca_path)))
{
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Unable to determine list of available "
"CA certificates for client authentication");
return HTTP_FORBIDDEN;
}
SSL_set_client_CA_list(ssl, ca_list);
renegotiate = TRUE;
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"Changed client verification locations will force "
"renegotiation");
}
#endif /* HAVE_SSL_SET_CERT_STORE */
/*
* SSL renegotiations in conjunction with HTTP
* requests using the POST method are not supported.
*
* Background:
*
* 1. When the client sends a HTTP/HTTPS request, Apache's core code
* reads only the request line ("METHOD /path HTTP/x.y") and the
* attached MIME headers ("Foo: bar") up to the terminating line ("CR
* LF"). An attached request body (for instance the data of a POST
* method) is _NOT_ read. Instead it is read by mod_cgi's content
* handler and directly passed to the CGI script.
*
* 2. mod_ssl supports per-directory re-configuration of SSL parameters.
* This is implemented by performing an SSL renegotiation of the
* re-configured parameters after the request is read, but before the
* response is sent. In more detail: the renegotiation happens after the
* request line and MIME headers were read, but _before_ the attached
* request body is read. The reason simply is that in the HTTP protocol
* usually there is no acknowledgment step between the headers and the
* body (there is the 100-continue feature and the chunking facility
* only), so Apache has no API hook for this step.
*
* 3. the problem now occurs when the client sends a POST request for
* URL /foo via HTTPS the server and the server has SSL parameters
* re-configured on a per-URL basis for /foo. Then mod_ssl has to
* perform an SSL renegotiation after the request was read and before
* the response is sent. But the problem is the pending POST body data
* in the receive buffer of SSL (which Apache still has not read - it's
* pending until mod_cgi sucks it in). When mod_ssl now tries to perform
* the renegotiation the pending data leads to an I/O error.
*
* Solution Idea:
*
* There are only two solutions: Either to simply state that POST
* requests to URLs with SSL re-configurations are not allowed, or to
* renegotiate really after the _complete_ request (i.e. including
* the POST body) was read. Obviously the latter would be preferred,
* but it cannot be done easily inside Apache, because as already
* mentioned, there is no API step between the body reading and the body
* processing. And even when we mod_ssl would hook directly into the
* loop of mod_cgi, we wouldn't solve the problem for other handlers, of
* course. So the only general solution is to suck in the pending data
* of the request body from the OpenSSL BIO into the Apache BUFF. Then
* the renegotiation can be done and after this step Apache can proceed
* processing the request as before.
*
* Solution Implementation:
*
* We cannot simply suck in the data via an SSL_read-based loop because of
* HTTP chunking. Instead we _have_ to use the Apache API for this step which
* is aware of HTTP chunking. So the trick is to suck in the pending request
* data via the Apache API (which uses Apache's BUFF code and in the
* background mod_ssl's I/O glue code) and re-inject it later into the Apache
* BUFF code again. This way the data flows twice through the Apache BUFF, of
* course. But this way the solution doesn't depend on any Apache specifics
* and is fully transparent to Apache modules.
*
* !! BUT ALL THIS IS STILL NOT RE-IMPLEMENTED FOR APACHE 2.0 !!
*/
if (renegotiate && !renegotiate_quick && (r->method_number == M_POST)) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"SSL Re-negotiation in conjunction "
"with POST method not supported!\n"
"hint: try SSLOptions +OptRenegotiate");
return HTTP_METHOD_NOT_ALLOWED;
}
/*
* now do the renegotiation if anything was actually reconfigured
*/
if (renegotiate) {
/*
* Now we force the SSL renegotation by sending the Hello Request
* message to the client. Here we have to do a workaround: Actually
* OpenSSL returns immediately after sending the Hello Request (the
* intent AFAIK is because the SSL/TLS protocol says it's not a must
* that the client replies to a Hello Request). But because we insist
* on a reply (anything else is an error for us) we have to go to the
* ACCEPT state manually. Using SSL_set_accept_state() doesn't work
* here because it resets too much of the connection. So we set the
* state explicitly and continue the handshake manually.
*/
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"Requesting connection re-negotiation");
if (renegotiate_quick) {
STACK_OF(X509) *cert_stack;
/* perform just a manual re-verification of the peer */
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"Performing quick renegotiation: "
"just re-verifying the peer");
cert_stack = (STACK_OF(X509) *)SSL_get_peer_cert_chain(ssl);
cert = SSL_get_peer_certificate(ssl);
if (!cert_stack && cert) {
/* client cert is in the session cache, but there is
* no chain, since ssl3_get_client_certificate()
* sk_X509_shift-ed the peer cert out of the chain.
* we put it back here for the purpose of quick_renegotiation.
*/
cert_stack = sk_new_null();
sk_X509_push(cert_stack, MODSSL_PCHAR_CAST cert);
}
if (!cert_stack || (sk_X509_num(cert_stack) == 0)) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Cannot find peer certificate chain");
return HTTP_FORBIDDEN;
}
if (!(cert_store ||
(cert_store = SSL_CTX_get_cert_store(ctx))))
{
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Cannot find certificate storage");
return HTTP_FORBIDDEN;
}
if (!cert) {
cert = sk_X509_value(cert_stack, 0);
}
X509_STORE_CTX_init(&cert_store_ctx, cert_store, cert, cert_stack);
depth = SSL_get_verify_depth(ssl);
if (depth >= 0) {
X509_STORE_CTX_set_depth(&cert_store_ctx, depth);
}
X509_STORE_CTX_set_ex_data(&cert_store_ctx,
SSL_get_ex_data_X509_STORE_CTX_idx(),
(char *)ssl);
if (!modssl_X509_verify_cert(&cert_store_ctx)) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Re-negotiation verification step failed");
ssl_log_ssl_error(APLOG_MARK, APLOG_ERR, r->server);
}
SSL_set_verify_result(ssl, cert_store_ctx.error);
X509_STORE_CTX_cleanup(&cert_store_ctx);
if (cert_stack != SSL_get_peer_cert_chain(ssl)) {
/* we created this ourselves, so free it */
sk_X509_pop_free(cert_stack, X509_free);
}
}
else {
request_rec *id = r->main ? r->main : r;
/* do a full renegotiation */
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"Performing full renegotiation: "
"complete handshake protocol");
SSL_set_session_id_context(ssl,
(unsigned char *)&id,
sizeof(id));
SSL_renegotiate(ssl);
SSL_do_handshake(ssl);
if (SSL_get_state(ssl) != SSL_ST_OK) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Re-negotiation request failed");
return HTTP_FORBIDDEN;
}
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"Awaiting re-negotiation handshake");
SSL_set_state(ssl, SSL_ST_ACCEPT);
SSL_do_handshake(ssl);
if (SSL_get_state(ssl) != SSL_ST_OK) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Re-negotiation handshake failed: "
"Not accepted by client!?");
return HTTP_FORBIDDEN;
}
}
/*
* Remember the peer certificate's DN
*/
if ((cert = SSL_get_peer_certificate(ssl))) {
if (sslconn->client_cert) {
X509_free(sslconn->client_cert);
}
sslconn->client_cert = cert;
sslconn->client_dn = NULL;
}
/*
* Finally check for acceptable renegotiation results
*/
if (dc->nVerifyClient != SSL_CVERIFY_NONE) {
BOOL do_verify = (dc->nVerifyClient == SSL_CVERIFY_REQUIRE);
if (do_verify && (SSL_get_verify_result(ssl) != X509_V_OK)) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Re-negotiation handshake failed: "
"Client verification failed");
return HTTP_FORBIDDEN;
}
if (do_verify) {
if ((peercert = SSL_get_peer_certificate(ssl)) == NULL) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"Re-negotiation handshake failed: "
"Client certificate missing");
return HTTP_FORBIDDEN;
}
X509_free(peercert);
}
}
}
/*
* Check SSLRequire boolean expressions
*/
requires = dc->aRequirement;
ssl_requires = (ssl_require_t *)requires->elts;
for (i = 0; i < requires->nelts; i++) {
ssl_require_t *req = &ssl_requires[i];
ok = ssl_expr_exec(r, req->mpExpr);
if (ok < 0) {
cp = apr_psprintf(r->pool,
"Failed to execute "
"SSL requirement expression: %s",
ssl_expr_get_error());
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
"access to %s failed, reason: %s",
r->filename, cp);
/* remember forbidden access for strict require option */
apr_table_setn(r->notes, "ssl-access-forbidden", "1");
return HTTP_FORBIDDEN;
}
if (ok != 1) {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"Access to %s denied for %s "
"(requirement expression not fulfilled)",
r->filename, r->connection->remote_ip);
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"Failed expression: %s", req->cpExpr);
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
"access to %s failed, reason: %s",
r->filename,
"SSL requirement expression not fulfilled "
"(see SSL logfile for more details)");
/* remember forbidden access for strict require option */
apr_table_setn(r->notes, "ssl-access-forbidden", "1");
return HTTP_FORBIDDEN;
}
}
/*
* Else access is granted from our point of view (except vendor
* handlers override). But we have to return DECLINED here instead
* of OK, because mod_auth and other modules still might want to
* deny access.
*/
return DECLINED;
}
/*
* Authentication Handler:
* Fake a Basic authentication from the X509 client certificate.
*
* This must be run fairly early on to prevent a real authentication from
* occuring, in particular it must be run before anything else that
* authenticates a user. This means that the Module statement for this
* module should be LAST in the Configuration file.
*/
int ssl_hook_UserCheck(request_rec *r)
{
SSLConnRec *sslconn = myConnConfig(r->connection);
SSLSrvConfigRec *sc = mySrvConfig(r->server);
SSLDirConfigRec *dc = myDirConfig(r);
char buf1[MAX_STRING_LEN], buf2[MAX_STRING_LEN];
char *clientdn;
const char *auth_line, *username, *password;
/*
* Additionally forbid access (again)
* when strict require option is used.
*/
if ((dc->nOptions & SSL_OPT_STRICTREQUIRE) &&
(apr_table_get(r->notes, "ssl-access-forbidden")))
{
return HTTP_FORBIDDEN;
}
/*
* Make sure the user is not able to fake the client certificate
* based authentication by just entering an X.509 Subject DN
* ("/XX=YYY/XX=YYY/..") as the username and "password" as the
* password.
*/
if ((auth_line = apr_table_get(r->headers_in, "Authorization"))) {
if (strcEQ(ap_getword(r->pool, &auth_line, ' '), "Basic")) {
while ((*auth_line == ' ') || (*auth_line == '\t')) {
auth_line++;
}
auth_line = ap_pbase64decode(r->pool, auth_line);
username = ap_getword_nulls(r->pool, &auth_line, ':');
password = auth_line;
if ((username[0] == '/') && strEQ(password, "password")) {
return HTTP_FORBIDDEN;
}
}
}
/*
* We decline operation in various situations...
* - SSLOptions +FakeBasicAuth not configured
* - r->user already authenticated
* - ssl not enabled
* - client did not present a certificate
*/
if (!(sc->enabled && sslconn->ssl && sslconn->client_cert) ||
!(dc->nOptions & SSL_OPT_FAKEBASICAUTH) || r->user)
{
return DECLINED;
}
if (!sslconn->client_dn) {
X509_NAME *name = X509_get_subject_name(sslconn->client_cert);
char *cp = X509_NAME_oneline(name, NULL, 0);
sslconn->client_dn = apr_pstrdup(r->connection->pool, cp);
modssl_free(cp);
}
clientdn = (char *)sslconn->client_dn;
/*
* Fake a password - which one would be immaterial, as, it seems, an empty
* password in the users file would match ALL incoming passwords, if only
* we were using the standard crypt library routine. Unfortunately, OpenSSL
* "fixes" a "bug" in crypt and thus prevents blank passwords from
* working. (IMHO what they really fix is a bug in the users of the code
* - failing to program correctly for shadow passwords). We need,
* therefore, to provide a password. This password can be matched by
* adding the string "xxj31ZMTZzkVA" as the password in the user file.
* This is just the crypted variant of the word "password" ;-)
*/
apr_snprintf(buf1, sizeof(buf1), "%s:password", clientdn);
ssl_util_uuencode(buf2, buf1, FALSE);
apr_snprintf(buf1, sizeof(buf1), "Basic %s", buf2);
apr_table_set(r->headers_in, "Authorization", buf1);
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"Faking HTTP Basic Auth header: \"Authorization: %s\"", buf1);
return DECLINED;
}
/* authorization phase */
int ssl_hook_Auth(request_rec *r)
{
SSLDirConfigRec *dc = myDirConfig(r);
/*
* Additionally forbid access (again)
* when strict require option is used.
*/
if ((dc->nOptions & SSL_OPT_STRICTREQUIRE) &&
(apr_table_get(r->notes, "ssl-access-forbidden")))
{
return HTTP_FORBIDDEN;
}
return DECLINED;
}
/*
* Fixup Handler
*/
static const char *ssl_hook_Fixup_vars[] = {
"SSL_VERSION_INTERFACE",
"SSL_VERSION_LIBRARY",
"SSL_PROTOCOL",
"SSL_CIPHER",
"SSL_CIPHER_EXPORT",
"SSL_CIPHER_USEKEYSIZE",
"SSL_CIPHER_ALGKEYSIZE",
"SSL_CLIENT_VERIFY",
"SSL_CLIENT_M_VERSION",
"SSL_CLIENT_M_SERIAL",
"SSL_CLIENT_V_START",
"SSL_CLIENT_V_END",
"SSL_CLIENT_S_DN",
"SSL_CLIENT_S_DN_C",
"SSL_CLIENT_S_DN_ST",
"SSL_CLIENT_S_DN_L",
"SSL_CLIENT_S_DN_O",
"SSL_CLIENT_S_DN_OU",
"SSL_CLIENT_S_DN_CN",
"SSL_CLIENT_S_DN_T",
"SSL_CLIENT_S_DN_I",
"SSL_CLIENT_S_DN_G",
"SSL_CLIENT_S_DN_S",
"SSL_CLIENT_S_DN_D",
"SSL_CLIENT_S_DN_UID",
"SSL_CLIENT_S_DN_Email",
"SSL_CLIENT_I_DN",
"SSL_CLIENT_I_DN_C",
"SSL_CLIENT_I_DN_ST",
"SSL_CLIENT_I_DN_L",
"SSL_CLIENT_I_DN_O",
"SSL_CLIENT_I_DN_OU",
"SSL_CLIENT_I_DN_CN",
"SSL_CLIENT_I_DN_T",
"SSL_CLIENT_I_DN_I",
"SSL_CLIENT_I_DN_G",
"SSL_CLIENT_I_DN_S",
"SSL_CLIENT_I_DN_D",
"SSL_CLIENT_I_DN_UID",
"SSL_CLIENT_I_DN_Email",
"SSL_CLIENT_A_KEY",
"SSL_CLIENT_A_SIG",
"SSL_SERVER_M_VERSION",
"SSL_SERVER_M_SERIAL",
"SSL_SERVER_V_START",
"SSL_SERVER_V_END",
"SSL_SERVER_S_DN",
"SSL_SERVER_S_DN_C",
"SSL_SERVER_S_DN_ST",
"SSL_SERVER_S_DN_L",
"SSL_SERVER_S_DN_O",
"SSL_SERVER_S_DN_OU",
"SSL_SERVER_S_DN_CN",
"SSL_SERVER_S_DN_T",
"SSL_SERVER_S_DN_I",
"SSL_SERVER_S_DN_G",
"SSL_SERVER_S_DN_S",
"SSL_SERVER_S_DN_D",
"SSL_SERVER_S_DN_UID",
"SSL_SERVER_S_DN_Email",
"SSL_SERVER_I_DN",
"SSL_SERVER_I_DN_C",
"SSL_SERVER_I_DN_ST",
"SSL_SERVER_I_DN_L",
"SSL_SERVER_I_DN_O",
"SSL_SERVER_I_DN_OU",
"SSL_SERVER_I_DN_CN",
"SSL_SERVER_I_DN_T",
"SSL_SERVER_I_DN_I",
"SSL_SERVER_I_DN_G",
"SSL_SERVER_I_DN_S",
"SSL_SERVER_I_DN_D",
"SSL_SERVER_I_DN_UID",
"SSL_SERVER_I_DN_Email",
"SSL_SERVER_A_KEY",
"SSL_SERVER_A_SIG",
"SSL_SESSION_ID",
NULL
};
int ssl_hook_Fixup(request_rec *r)
{
SSLConnRec *sslconn = myConnConfig(r->connection);
SSLSrvConfigRec *sc = mySrvConfig(r->server);
SSLDirConfigRec *dc = myDirConfig(r);
apr_table_t *env = r->subprocess_env;
char *var, *val = "";
STACK_OF(X509) *peer_certs;
SSL *ssl;
int i;
/*
* Check to see if SSL is on
*/
if (!(sc->enabled && sslconn && (ssl = sslconn->ssl))) {
return DECLINED;
}
/*
* Annotate the SSI/CGI environment with standard SSL information
*/
/* the always present HTTPS (=HTTP over SSL) flag! */
apr_table_setn(env, "HTTPS", "on");
/* standard SSL environment variables */
if (dc->nOptions & SSL_OPT_STDENVVARS) {
for (i = 0; ssl_hook_Fixup_vars[i]; i++) {
var = (char *)ssl_hook_Fixup_vars[i];
val = ssl_var_lookup(r->pool, r->server, r->connection, r, var);
if (!strIsEmpty(val)) {
apr_table_setn(env, var, val);
}
}
}
/*
* On-demand bloat up the SSI/CGI environment with certificate data
*/
if (dc->nOptions & SSL_OPT_EXPORTCERTDATA) {
val = ssl_var_lookup(r->pool, r->server, r->connection,
r, "SSL_SERVER_CERT");
apr_table_setn(env, "SSL_SERVER_CERT", val);
val = ssl_var_lookup(r->pool, r->server, r->connection,
r, "SSL_CLIENT_CERT");
apr_table_setn(env, "SSL_CLIENT_CERT", val);
if ((peer_certs = (STACK_OF(X509) *)SSL_get_peer_cert_chain(ssl))) {
for (i = 0; i < sk_X509_num(peer_certs); i++) {
var = apr_psprintf(r->pool, "SSL_CLIENT_CERT_CHAIN_%d", i);
val = ssl_var_lookup(r->pool, r->server, r->connection,
r, var);
if (val) {
apr_table_setn(env, var, val);
}
}
}
}
return DECLINED;
}
/* _________________________________________________________________
**
** OpenSSL Callback Functions
** _________________________________________________________________
*/
/*
* Handle out temporary RSA private keys on demand
*
* The background of this as the TLSv1 standard explains it:
*
* | D.1. Temporary RSA keys
* |
* | US Export restrictions limit RSA keys used for encryption to 512
* | bits, but do not place any limit on lengths of RSA keys used for
* | signing operations. Certificates often need to be larger than 512
* | bits, since 512-bit RSA keys are not secure enough for high-value
* | transactions or for applications requiring long-term security. Some
* | certificates are also designated signing-only, in which case they
* | cannot be used for key exchange.
* |
* | When the public key in the certificate cannot be used for encryption,
* | the server signs a temporary RSA key, which is then exchanged. In
* | exportable applications, the temporary RSA key should be the maximum
* | allowable length (i.e., 512 bits). Because 512-bit RSA keys are
* | relatively insecure, they should be changed often. For typical
* | electronic commerce applications, it is suggested that keys be
* | changed daily or every 500 transactions, and more often if possible.
* | Note that while it is acceptable to use the same temporary key for
* | multiple transactions, it must be signed each time it is used.
* |
* | RSA key generation is a time-consuming process. In many cases, a
* | low-priority process can be assigned the task of key generation.
* | Whenever a new key is completed, the existing temporary key can be
* | replaced with the new one.
*
* XXX: base on comment above, if thread support is enabled,
* we should spawn a low-priority thread to generate new keys
* on the fly.
*
* So we generated 512 and 1024 bit temporary keys on startup
* which we now just hand out on demand....
*/
RSA *ssl_callback_TmpRSA(SSL *ssl, int export, int keylen)
{
conn_rec *c = (conn_rec *)SSL_get_app_data(ssl);
SSLModConfigRec *mc = myModConfig(c->base_server);
int idx;
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, c->base_server,
"handing out temporary %d bit RSA key", keylen);
/* doesn't matter if export flag is on,
* we won't be asked for keylen > 512 in that case.
* if we are asked for a keylen > 1024, it is too expensive
* to generate on the fly.
* XXX: any reason not to generate 2048 bit keys at startup?
*/
switch (keylen) {
case 512:
idx = SSL_TMP_KEY_RSA_512;
break;
case 1024:
default:
idx = SSL_TMP_KEY_RSA_1024;
}
return (RSA *)mc->pTmpKeys[idx];
}
/*
* Hand out the already generated DH parameters...
*/
DH *ssl_callback_TmpDH(SSL *ssl, int export, int keylen)
{
conn_rec *c = (conn_rec *)SSL_get_app_data(ssl);
SSLModConfigRec *mc = myModConfig(c->base_server);
int idx;
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, c->base_server,
"handing out temporary %d bit DH key", keylen);
switch (keylen) {
case 512:
idx = SSL_TMP_KEY_DH_512;
break;
case 1024:
default:
idx = SSL_TMP_KEY_DH_1024;
}
return (DH *)mc->pTmpKeys[idx];
}
/*
* This OpenSSL callback function is called when OpenSSL
* does client authentication and verifies the certificate chain.
*/
int ssl_callback_SSLVerify(int ok, X509_STORE_CTX *ctx)
{
/* Get Apache context back through OpenSSL context */
SSL *ssl = (SSL *)X509_STORE_CTX_get_app_data(ctx);
conn_rec *conn = (conn_rec *)SSL_get_app_data(ssl);
server_rec *s = conn->base_server;
request_rec *r = (request_rec *)SSL_get_app_data2(ssl);
SSLSrvConfigRec *sc = mySrvConfig(s);
SSLDirConfigRec *dc = r ? myDirConfig(r) : NULL;
SSLConnRec *sslconn = myConnConfig(conn);
modssl_ctx_t *mctx = myCtxConfig(sslconn, sc);
/* Get verify ingredients */
int errnum = X509_STORE_CTX_get_error(ctx);
int errdepth = X509_STORE_CTX_get_error_depth(ctx);
int depth, verify;
/*
* Log verification information
*/
if (s->loglevel >= APLOG_DEBUG) {
X509 *cert = X509_STORE_CTX_get_current_cert(ctx);
char *sname = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0);
char *iname = X509_NAME_oneline(X509_get_issuer_name(cert), NULL, 0);
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"Certificate Verification: "
"depth: %d, subject: %s, issuer: %s",
errdepth,
sname ? sname : "-unknown-",
iname ? iname : "-unknown-");
if (sname) {
modssl_free(sname);
}
if (iname) {
modssl_free(iname);
}
}
/*
* Check for optionally acceptable non-verifiable issuer situation
*/
if (dc && (dc->nVerifyClient != SSL_CVERIFY_UNSET)) {
verify = dc->nVerifyClient;
}
else {
verify = mctx->auth.verify_mode;
}
if (verify == SSL_CVERIFY_NONE) {
/*
* SSLProxyVerify is either not configured or set to "none".
* (this callback doesn't happen in the server context if SSLVerify
* is not configured or set to "none")
*/
return TRUE;
}
if (ssl_verify_error_is_optional(errnum) &&
(verify == SSL_CVERIFY_OPTIONAL_NO_CA))
{
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"Certificate Verification: Verifiable Issuer is "
"configured as optional, therefore we're accepting "
"the certificate");
sslconn->verify_info = "GENEROUS";
ok = TRUE;
}
/*
* Additionally perform CRL-based revocation checks
*/
if (ok) {
if (!(ok = ssl_callback_SSLVerify_CRL(ok, ctx, conn))) {
errnum = X509_STORE_CTX_get_error(ctx);
}
}
/*
* If we already know it's not ok, log the real reason
*/
if (!ok) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
"Certificate Verification: Error (%d): %s",
errnum, X509_verify_cert_error_string(errnum));
if (sslconn->client_cert) {
X509_free(sslconn->client_cert);
sslconn->client_cert = NULL;
}
sslconn->client_dn = NULL;
sslconn->verify_error = X509_verify_cert_error_string(errnum);
}
/*
* Finally check the depth of the certificate verification
*/
if (dc && (dc->nVerifyDepth != UNSET)) {
depth = dc->nVerifyDepth;
}
else {
depth = mctx->auth.verify_depth;
}
if (errdepth > depth) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
"Certificate Verification: Certificate Chain too long "
"(chain has %d certificates, but maximum allowed are "
"only %d)",
errdepth, depth);
errnum = X509_V_ERR_CERT_CHAIN_TOO_LONG;
sslconn->verify_error = X509_verify_cert_error_string(errnum);
ok = FALSE;
}
/*
* And finally signal OpenSSL the (perhaps changed) state
*/
return ok;
}
int ssl_callback_SSLVerify_CRL(int ok, X509_STORE_CTX *ctx, conn_rec *c)
{
server_rec *s = c->base_server;
SSLSrvConfigRec *sc = mySrvConfig(s);
SSLConnRec *sslconn = myConnConfig(c);
modssl_ctx_t *mctx = myCtxConfig(sslconn, sc);
X509_OBJECT obj;
X509_NAME *subject, *issuer;
X509 *cert;
X509_CRL *crl;
EVP_PKEY *pubkey;
int i, n, rc;
/*
* Unless a revocation store for CRLs was created we
* cannot do any CRL-based verification, of course.
*/
if (!mctx->crl) {
return ok;
}
/*
* Determine certificate ingredients in advance
*/
cert = X509_STORE_CTX_get_current_cert(ctx);
subject = X509_get_subject_name(cert);
issuer = X509_get_issuer_name(cert);
/*
* OpenSSL provides the general mechanism to deal with CRLs but does not
* use them automatically when verifying certificates, so we do it
* explicitly here. We will check the CRL for the currently checked
* certificate, if there is such a CRL in the store.
*
* We come through this procedure for each certificate in the certificate
* chain, starting with the root-CA's certificate. At each step we've to
* both verify the signature on the CRL (to make sure it's a valid CRL)
* and it's revocation list (to make sure the current certificate isn't
* revoked). But because to check the signature on the CRL we need the
* public key of the issuing CA certificate (which was already processed
* one round before), we've a little problem. But we can both solve it and
* at the same time optimize the processing by using the following
* verification scheme (idea and code snippets borrowed from the GLOBUS
* project):
*
* 1. We'll check the signature of a CRL in each step when we find a CRL
* through the _subject_ name of the current certificate. This CRL
* itself will be needed the first time in the next round, of course.
* But we do the signature processing one round before this where the
* public key of the CA is available.
*
* 2. We'll check the revocation list of a CRL in each step when
* we find a CRL through the _issuer_ name of the current certificate.
* This CRLs signature was then already verified one round before.
*
* This verification scheme allows a CA to revoke its own certificate as
* well, of course.
*/
/*
* Try to retrieve a CRL corresponding to the _subject_ of
* the current certificate in order to verify it's integrity.
*/
memset((char *)&obj, 0, sizeof(obj));
rc = SSL_X509_STORE_lookup(mctx->crl,
X509_LU_CRL, subject, &obj);
crl = obj.data.crl;
if ((rc > 0) && crl) {
/*
* Log information about CRL
* (A little bit complicated because of ASN.1 and BIOs...)
*/
if (s->loglevel >= APLOG_DEBUG) {
char buff[512]; /* should be plenty */
BIO *bio = BIO_new(BIO_s_mem());
BIO_printf(bio, "CA CRL: Issuer: ");
X509_NAME_print(bio, issuer, 0);
BIO_printf(bio, ", lastUpdate: ");
ASN1_UTCTIME_print(bio, X509_CRL_get_lastUpdate(crl));
BIO_printf(bio, ", nextUpdate: ");
ASN1_UTCTIME_print(bio, X509_CRL_get_nextUpdate(crl));
n = BIO_read(bio, buff, sizeof(buff));
buff[n] = '\0';
BIO_free(bio);
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, buff);
}
/*
* Verify the signature on this CRL
*/
pubkey = X509_get_pubkey(cert);
rc = X509_CRL_verify(crl, pubkey);
#ifdef OPENSSL_VERSION_NUMBER
/* Only refcounted in OpenSSL */
if (pubkey)
EVP_PKEY_free(pubkey);
#endif
if (rc <= 0) {
ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s,
"Invalid signature on CRL");
X509_STORE_CTX_set_error(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE);
X509_OBJECT_free_contents(&obj);
return FALSE;
}
/*
* Check date of CRL to make sure it's not expired
*/
i = X509_cmp_current_time(X509_CRL_get_nextUpdate(crl));
if (i == 0) {
ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s,
"Found CRL has invalid nextUpdate field");
X509_STORE_CTX_set_error(ctx,
X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD);
X509_OBJECT_free_contents(&obj);
return FALSE;
}
if (i < 0) {
ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s,
"Found CRL is expired - "
"revoking all certificates until you get updated CRL");
X509_STORE_CTX_set_error(ctx, X509_V_ERR_CRL_HAS_EXPIRED);
X509_OBJECT_free_contents(&obj);
return FALSE;
}
X509_OBJECT_free_contents(&obj);
}
/*
* Try to retrieve a CRL corresponding to the _issuer_ of
* the current certificate in order to check for revocation.
*/
memset((char *)&obj, 0, sizeof(obj));
rc = SSL_X509_STORE_lookup(mctx->crl,
X509_LU_CRL, issuer, &obj);
crl = obj.data.crl;
if ((rc > 0) && crl) {
/*
* Check if the current certificate is revoked by this CRL
*/
n = sk_X509_REVOKED_num(X509_CRL_get_REVOKED(crl));
for (i = 0; i < n; i++) {
X509_REVOKED *revoked =
sk_X509_REVOKED_value(X509_CRL_get_REVOKED(crl), i);
ASN1_INTEGER *sn = X509_REVOKED_get_serialNumber(revoked);
if (!ASN1_INTEGER_cmp(sn, X509_get_serialNumber(cert))) {
if (s->loglevel >= APLOG_DEBUG) {
char *cp = X509_NAME_oneline(issuer, NULL, 0);
long serial = ASN1_INTEGER_get(sn);
ap_log_error(APLOG_MARK, APLOG_INFO, 0, s,
"Certificate with serial %ld (0x%lX) "
"revoked per CRL from issuer %s",
serial, serial, cp);
modssl_free(cp);
}
X509_STORE_CTX_set_error(ctx, X509_V_ERR_CERT_REVOKED);
X509_OBJECT_free_contents(&obj);
return FALSE;
}
}
X509_OBJECT_free_contents(&obj);
}
return ok;
}
#define SSLPROXY_CERT_CB_LOG_FMT \
"Proxy client certificate callback: (%s) "
static void modssl_proxy_info_log(server_rec *s,
X509_INFO *info,
const char *msg)
{
SSLSrvConfigRec *sc = mySrvConfig(s);
char name_buf[256];
X509_NAME *name;
char *dn;
if (s->loglevel < APLOG_DEBUG) {
return;
}
name = X509_get_subject_name(info->x509);
dn = X509_NAME_oneline(name, name_buf, sizeof(name_buf));
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
SSLPROXY_CERT_CB_LOG_FMT "%s, sending %s",
sc->vhost_id, msg, dn ? dn : "-uknown-");
}
/*
* caller will decrement the cert and key reference
* so we need to increment here to prevent them from
* being freed.
*/
#define modssl_set_cert_info(info, cert, pkey) \
*cert = info->x509; \
X509_reference_inc(*cert); \
*pkey = info->x_pkey->dec_pkey; \
EVP_PKEY_reference_inc(*pkey)
int ssl_callback_proxy_cert(SSL *ssl, MODSSL_CLIENT_CERT_CB_ARG_TYPE **x509, EVP_PKEY **pkey)
{
conn_rec *c = (conn_rec *)SSL_get_app_data(ssl);
server_rec *s = c->base_server;
SSLSrvConfigRec *sc = mySrvConfig(s);
X509_NAME *ca_name, *issuer;
X509_INFO *info;
STACK_OF(X509_NAME) *ca_list;
STACK_OF(X509_INFO) *certs = sc->proxy->pkp->certs;
int i, j;
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
SSLPROXY_CERT_CB_LOG_FMT "entered",
sc->vhost_id);
if (!certs || (sk_X509_INFO_num(certs) <= 0)) {
ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s,
SSLPROXY_CERT_CB_LOG_FMT
"downstream server wanted client certificate "
"but none are configured", sc->vhost_id);
return FALSE;
}
ca_list = SSL_get_client_CA_list(ssl);
if (!ca_list || (sk_X509_NAME_num(ca_list) <= 0)) {
/*
* downstream server didn't send us a list of acceptable CA certs,
* so we send the first client cert in the list.
*/
info = sk_X509_INFO_value(certs, 0);
modssl_proxy_info_log(s, info, "no acceptable CA list");
modssl_set_cert_info(info, x509, pkey);
return TRUE;
}
for (i = 0; i < sk_X509_NAME_num(ca_list); i++) {
ca_name = sk_X509_NAME_value(ca_list, i);
for (j = 0; j < sk_X509_INFO_num(certs); j++) {
info = sk_X509_INFO_value(certs, j);
issuer = X509_get_issuer_name(info->x509);
if (X509_NAME_cmp(issuer, ca_name) == 0) {
modssl_proxy_info_log(s, info, "found acceptable cert");
modssl_set_cert_info(info, x509, pkey);
return TRUE;
}
}
}
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
SSLPROXY_CERT_CB_LOG_FMT
"no client certificate found!?", sc->vhost_id);
return FALSE;
}
static void ssl_session_log(server_rec *s,
const char *request,
unsigned char *id,
unsigned int idlen,
const char *status,
const char *result,
long timeout)
{
char buf[SSL_SESSION_ID_STRING_LEN];
char timeout_str[56] = {'\0'};
if (s->loglevel < APLOG_DEBUG) {
return;
}
if (timeout) {
apr_snprintf(timeout_str, sizeof(timeout_str),
"timeout=%lds ", (timeout - time(NULL)));
}
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"Inter-Process Session Cache: "
"request=%s status=%s id=%s %s(session %s)",
request, status,
SSL_SESSION_id2sz(id, idlen, buf, sizeof(buf)),
timeout_str, result);
}
/*
* This callback function is executed by OpenSSL whenever a new SSL_SESSION is
* added to the internal OpenSSL session cache. We use this hook to spread the
* SSL_SESSION also to the inter-process disk-cache to make share it with our
* other Apache pre-forked server processes.
*/
int ssl_callback_NewSessionCacheEntry(SSL *ssl, SSL_SESSION *session)
{
/* Get Apache context back through OpenSSL context */
conn_rec *conn = (conn_rec *)SSL_get_app_data(ssl);
server_rec *s = conn->base_server;
SSLSrvConfigRec *sc = mySrvConfig(s);
long timeout = sc->session_cache_timeout;
BOOL rc;
unsigned char *id;
unsigned int idlen;
/*
* Set the timeout also for the internal OpenSSL cache, because this way
* our inter-process cache is consulted only when it's really necessary.
*/
SSL_set_timeout(session, timeout);
/*
* Store the SSL_SESSION in the inter-process cache with the
* same expire time, so it expires automatically there, too.
*/
id = SSL_SESSION_get_session_id(session);
idlen = SSL_SESSION_get_session_id_length(session);
timeout += modssl_session_get_time(session);
rc = ssl_scache_store(s, id, idlen, timeout, session);
ssl_session_log(s, "SET", id, idlen,
rc == TRUE ? "OK" : "BAD",
"caching", timeout);
/*
* return 0 which means to OpenSSL that the session is still
* valid and was not freed by us with SSL_SESSION_free().
*/
return 0;
}
/*
* This callback function is executed by OpenSSL whenever a
* SSL_SESSION is looked up in the internal OpenSSL cache and it
* was not found. We use this to lookup the SSL_SESSION in the
* inter-process disk-cache where it was perhaps stored by one
* of our other Apache pre-forked server processes.
*/
SSL_SESSION *ssl_callback_GetSessionCacheEntry(SSL *ssl,
unsigned char *id,
int idlen, int *do_copy)
{
/* Get Apache context back through OpenSSL context */
conn_rec *conn = (conn_rec *)SSL_get_app_data(ssl);
server_rec *s = conn->base_server;
SSL_SESSION *session;
/*
* Try to retrieve the SSL_SESSION from the inter-process cache
*/
session = ssl_scache_retrieve(s, id, idlen);
ssl_session_log(s, "GET", id, idlen,
session ? "FOUND" : "MISSED",
session ? "reuse" : "renewal", 0);
/*
* Return NULL or the retrieved SSL_SESSION. But indicate (by
* setting do_copy to 0) that the reference count on the
* SSL_SESSION should not be incremented by the SSL library,
* because we will no longer hold a reference to it ourself.
*/
*do_copy = 0;
return session;
}
/*
* This callback function is executed by OpenSSL whenever a
* SSL_SESSION is removed from the the internal OpenSSL cache.
* We use this to remove the SSL_SESSION in the inter-process
* disk-cache, too.
*/
void ssl_callback_DelSessionCacheEntry(SSL_CTX *ctx,
SSL_SESSION *session)
{
server_rec *s;
SSLSrvConfigRec *sc;
unsigned char *id;
unsigned int idlen;
/*
* Get Apache context back through OpenSSL context
*/
if (!(s = (server_rec *)SSL_CTX_get_app_data(ctx))) {
return; /* on server shutdown Apache is already gone */
}
sc = mySrvConfig(s);
/*
* Remove the SSL_SESSION from the inter-process cache
*/
id = SSL_SESSION_get_session_id(session);
idlen = SSL_SESSION_get_session_id_length(session);
ssl_scache_remove(s, id, idlen);
ssl_session_log(s, "REM", id, idlen,
"OK", "dead", 0);
return;
}
/*
* This callback function is executed while OpenSSL processes the
* SSL handshake and does SSL record layer stuff. We use it to
* trace OpenSSL's processing in out SSL logfile.
*/
void ssl_callback_LogTracingState(MODSSL_INFO_CB_ARG_TYPE ssl, int where, int rc)
{
conn_rec *c;
server_rec *s;
SSLSrvConfigRec *sc;
/*
* find corresponding server
*/
if (!(c = (conn_rec *)SSL_get_app_data((SSL *)ssl))) {
return;
}
s = c->base_server;
if (!(sc = mySrvConfig(s))) {
return;
}
/*
* create the various trace messages
*/
if (s->loglevel >= APLOG_DEBUG) {
if (where & SSL_CB_HANDSHAKE_START) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Handshake: start", SSL_LIBRARY_NAME);
}
else if (where & SSL_CB_HANDSHAKE_DONE) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Handshake: done", SSL_LIBRARY_NAME);
}
else if (where & SSL_CB_LOOP) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Loop: %s",
SSL_LIBRARY_NAME, SSL_state_string_long(ssl));
}
else if (where & SSL_CB_READ) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Read: %s",
SSL_LIBRARY_NAME, SSL_state_string_long(ssl));
}
else if (where & SSL_CB_WRITE) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Write: %s",
SSL_LIBRARY_NAME, SSL_state_string_long(ssl));
}
else if (where & SSL_CB_ALERT) {
char *str = (where & SSL_CB_READ) ? "read" : "write";
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Alert: %s:%s:%s\n",
SSL_LIBRARY_NAME, str,
SSL_alert_type_string_long(rc),
SSL_alert_desc_string_long(rc));
}
else if (where & SSL_CB_EXIT) {
if (rc == 0) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Exit: failed in %s",
SSL_LIBRARY_NAME, SSL_state_string_long(ssl));
}
else if (rc < 0) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"%s: Exit: error in %s",
SSL_LIBRARY_NAME, SSL_state_string_long(ssl));
}
}
}
/*
* Because SSL renegotations can happen at any time (not only after
* SSL_accept()), the best way to log the current connection details is
* right after a finished handshake.
*/
if (where & SSL_CB_HANDSHAKE_DONE) {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, s,
"Connection: Client IP: %s, Protocol: %s, "
"Cipher: %s (%s/%s bits)",
ssl_var_lookup(NULL, s, c, NULL, "REMOTE_ADDR"),
ssl_var_lookup(NULL, s, c, NULL, "SSL_PROTOCOL"),
ssl_var_lookup(NULL, s, c, NULL, "SSL_CIPHER"),
ssl_var_lookup(NULL, s, c, NULL, "SSL_CIPHER_USEKEYSIZE"),
ssl_var_lookup(NULL, s, c, NULL, "SSL_CIPHER_ALGKEYSIZE"));
}
}