ssl_scache_memcache.c revision 341bd61e8bccf51d8f2a5580168272e6e9098500
/* 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_scache_memcache.c
* Distributed Session Cache on top of memcached
*/
#include "ssl_private.h"
#ifdef HAVE_SSL_CACHE_MEMCACHE
#include "apr_memcache.h"
#include "ap_mpm.h"
/*
* SSL Session Caching using memcached as a backend.
*/
/*
**
** High-Level "handlers" as per ssl_scache.c
**
*/
/* The underlying apr_memcache system is thread safe.. */
#define MC_TAG "mod_ssl:"
#define MC_TAG_LEN \
(sizeof(MC_TAG))
#define MC_KEY_LEN 254
#ifndef MC_DEFAULT_SERVER_PORT
#define MC_DEFAULT_SERVER_PORT 11211
#endif
#ifndef MC_DEFAULT_SERVER_MIN
#define MC_DEFAULT_SERVER_MIN 0
#endif
#ifndef MC_DEFAULT_SERVER_SMAX
#define MC_DEFAULT_SERVER_SMAX 1
#endif
#ifndef MC_DEFAULT_SERVER_TTL
#define MC_DEFAULT_SERVER_TTL 600
#endif
struct context {
const char *servers;
apr_memcache_t *mc;
};
static const char *ssl_scache_mc_create(void **context, const char *arg,
apr_pool_t *tmp, apr_pool_t *p)
{
struct context *ctx;
*context = ctx = apr_palloc(p, sizeof *ctx);
ctx->servers = apr_pstrdup(p, arg);
return NULL;
}
static apr_status_t ssl_scache_mc_init(void *context, server_rec *s, apr_pool_t *p)
{
apr_status_t rv;
int thread_limit = 0;
int nservers = 0;
char *cache_config;
char *split;
char *tok;
struct context *ctx = context;
ap_mpm_query(AP_MPMQ_HARD_LIMIT_THREADS, &thread_limit);
/* Find all the servers in the first run to get a total count */
cache_config = apr_pstrdup(p, ctx->servers);
split = apr_strtok(cache_config, ",", &tok);
while (split) {
nservers++;
split = apr_strtok(NULL,",", &tok);
}
rv = apr_memcache_create(p, nservers, 0, &ctx->mc);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s,
"SSLSessionCache: Failed to create Memcache Object of '%d' size.",
nservers);
return rv;
}
/* Now add each server to the memcache */
cache_config = apr_pstrdup(p, ctx->servers);
split = apr_strtok(cache_config, ",", &tok);
while (split) {
apr_memcache_server_t *st;
char *host_str;
char *scope_id;
apr_port_t port;
rv = apr_parse_addr_port(&host_str, &scope_id, &port, split, p);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s,
"SSLSessionCache: Failed to Parse Server: '%s'", split);
return rv;
}
if (host_str == NULL) {
ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s,
"SSLSessionCache: Failed to Parse Server, "
"no hostname specified: '%s'", split);
return APR_EINVAL;
}
if (port == 0) {
port = MC_DEFAULT_SERVER_PORT;
}
rv = apr_memcache_server_create(p,
host_str, port,
MC_DEFAULT_SERVER_MIN,
MC_DEFAULT_SERVER_SMAX,
thread_limit,
MC_DEFAULT_SERVER_TTL,
&st);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s,
"SSLSessionCache: Failed to Create Server: %s:%d",
host_str, port);
return rv;
}
rv = apr_memcache_add_server(ctx->mc, st);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s,
"SSLSessionCache: Failed to Add Server: %s:%d",
host_str, port);
return rv;
}
split = apr_strtok(NULL,",", &tok);
}
return APR_SUCCESS;
}
static void ssl_scache_mc_kill(void *context, server_rec *s)
{
/* noop. */
}
static char *mc_session_id2sz(const unsigned char *id, unsigned int idlen,
char *str, int strsize)
{
char *cp;
int n;
int maxlen = (strsize - MC_TAG_LEN)/2;
cp = apr_cpystrn(str, MC_TAG, MC_TAG_LEN);
for (n = 0; n < idlen && n < maxlen; n++) {
apr_snprintf(cp, 3, "%02X", (unsigned) id[n]);
cp += 2;
}
*cp = '\0';
return str;
}
static apr_status_t ssl_scache_mc_store(void *context, server_rec *s,
const unsigned char *id, unsigned int idlen,
time_t timeout,
unsigned char *ucaData, unsigned int nData)
{
struct context *ctx = context;
char buf[MC_KEY_LEN];
char *strkey = NULL;
apr_status_t rv;
strkey = mc_session_id2sz(id, idlen, buf, sizeof(buf));
if(!strkey) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, "scache_mc: Key generation borked.");
return APR_EGENERAL;
}
rv = apr_memcache_set(ctx->mc, strkey, (char*)ucaData, nData, timeout, 0);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s,
"scache_mc: error setting key '%s' "
"with %d bytes of data", strkey, nData);
return rv;
}
return APR_SUCCESS;
}
static apr_status_t ssl_scache_mc_retrieve(void *context, server_rec *s,
const unsigned char *id, unsigned int idlen,
unsigned char *dest, unsigned int *destlen,
apr_pool_t *p)
{
struct context *ctx = context;
apr_size_t der_len;
char buf[MC_KEY_LEN], *der;
char *strkey = NULL;
apr_status_t rv;
strkey = mc_session_id2sz(id, idlen, buf, sizeof(buf));
if (!strkey) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
"scache_mc: Key generation borked.");
return APR_EGENERAL;
}
/* ### this could do with a subpool, but _getp looks like it will
* eat memory like it's going out of fashion anyway. */
rv = apr_memcache_getp(ctx->mc, p, strkey,
&der, &der_len, NULL);
if (rv) {
if (rv != APR_NOTFOUND) {
ap_log_error(APLOG_MARK, APLOG_ERR, rv, s,
"scache_mc: 'get_session' FAIL");
}
return rv;
}
else if (der_len > *destlen) {
ap_log_error(APLOG_MARK, APLOG_ERR, rv, s,
"scache_mc: 'get_session' OVERFLOW");
return rv;
}
memcpy(dest, der, der_len);
*destlen = der_len;
return APR_SUCCESS;
}
static void ssl_scache_mc_remove(void *context, server_rec *s,
const unsigned char *id, unsigned int idlen,
apr_pool_t *p)
{
struct context *ctx = context;
char buf[MC_KEY_LEN];
char* strkey = NULL;
apr_status_t rv;
strkey = mc_session_id2sz(id, idlen, buf, sizeof(buf));
if(!strkey) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, "scache_mc: Key generation borked.");
return;
}
rv = apr_memcache_delete(ctx->mc, strkey, 0);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, rv, s,
"scache_mc: error deleting key '%s' ",
strkey);
return;
}
}
static void ssl_scache_mc_status(void *context, request_rec *r, int flags)
{
/* SSLModConfigRec *mc = myModConfig(r->server); */
/* TODO: Make a mod_status handler. meh. */
}
const modssl_sesscache_provider modssl_sesscache_mc = {
"memcache",
0,
ssl_scache_mc_create,
ssl_scache_mc_init,
ssl_scache_mc_kill,
ssl_scache_mc_store,
ssl_scache_mc_retrieve,
ssl_scache_mc_remove,
ssl_scache_mc_status
};
#endif