Replay POST requets after been sent to the IdP

git-svn-id: https://modmellon.googlecode.com/svn/trunk@67 a716ebb1-153a-0410-b759-cfb97c6a1b53

7 files changed, 614 insertions, 65 deletions

diff --git a/NEWS b/NEWS
index a9c1621..c6e2dc3 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,8 @@
+Version 0.2.5
+---------------------------------------------------------------------------
+
+* Replay POST requests after been sent to the IdP
+
 Version 0.2.4
 ---------------------------------------------------------------------------
 
diff --git a/README b/README
index c01e00e..894574a 100644
--- a/README
+++ b/README
@@ -104,6 +104,25 @@ MellonCacheSize 100
 # Default: MellonLockFile "/tmp/mellonLock"
 MellonLockFile "/tmp/mellonLock"
 
+# MellonPostDir is the full path of a directory where POST requests are
+# saved during authentication. This directory must be owned by the Apache
+# user and be mode 700. We will attempt to create it if it does not exist.
+# Default: MellonPostDir "/var/tmp/mellonpost"
+MellonPostDir "/var/tmp/mellonpost"
+
+# MellonPostTTL is the delay in seconds before a saved POST request can
+# be flushed.
+# Default: MellonPostTTL 900 (15 mn)
+MellonPostTTL 900
+
+# MellonPostSize is the maximum size for saved POST requests
+# Default: MellonPostSize 1073741824 (1 MB)
+MellonPostSize 1073741824
+
+# MellonPostCount is the maxmimum amount of saved POST requests
+# Default: MellonPostCount 100
+MellonPostCount 100
+
 ###########################################################################
 # End of global configuration for mod_auth_mellon.
 ###########################################################################
diff --git a/auth_mellon.h b/auth_mellon.h
index be56b6d..807668a 100644
--- a/auth_mellon.h
+++ b/auth_mellon.h
@@ -89,6 +89,10 @@
 typedef struct am_mod_cfg_rec {
     int cache_size;
     const char *lock_file;
+    const char *post_dir;
+    apr_time_t post_ttl;
+    int post_count;
+    apr_size_t post_size;
 
     /* These variables can't be allowed to change after the session store
      * has been initialized. Therefore we copy them before initializing
@@ -257,11 +261,15 @@ char *am_urlencode(apr_pool_t *pool, const char *str);
 int am_urldecode(char *data);
 char *am_generate_session_id(request_rec *r);
 char *am_getfile(apr_pool_t *conf, server_rec *s, const char *file);
+char *am_get_endpoint_url(request_rec *r);
+int am_postdir_cleanup(request_rec *s);
+char *am_htmlencode(request_rec *r, const char *str);
+int am_save_post(request_rec *r, const char **relay_state);
 
 
 int am_auth_mellon_user(request_rec *r);
 int am_check_uid(request_rec *r);
-int am_handle_metadata(request_rec *r);
+int am_handler(request_rec *r);
 
 
 int am_httpclient_get(request_rec *r, const char *uri, 
diff --git a/auth_mellon_config.c b/auth_mellon_config.c
index e99062d..ada0ee6 100644
--- a/auth_mellon_config.c
+++ b/auth_mellon_config.c
@@ -56,6 +56,25 @@ static const int default_dump_saml_response = 0;
  */
 static const char *default_login_path = "/";
 
+/* This is the directory for storing saved POST sessions
+ * the MellonPostDirectory configuration directive if you change this.
+ */
+static const char *post_dir = "/var/tmp/mellonpost";
+
+/* saved POST session time to live
+ * the MellonPostTTL configuration directive if you change this.
+ */
+static const apr_time_t post_ttl = 15 * 60;
+
+/* saved POST session maximum size
+ * the MellonPostSize configuration directive if you change this.
+ */
+static const apr_size_t post_size = 1024 * 1024 * 1024;
+
+/* maximum saved POST sessions
+ * the MellonPostCount configuration directive if you change this.
+ */
+static const int post_count = 100;
 
 /* This function handles configuration directives which set a file
  * slot in the module configuration. If lasso is recent enough, it
@@ -454,6 +473,38 @@ const command_rec auth_mellon_commands[] = {
         "The lock file for session synchronization."
         " Default value is \"/tmp/mellonLock\"."
         ), 
+    AP_INIT_TAKE1(
+        "MellonPostDirectory",
+        am_set_module_config_string_slot,
+        (void *)APR_OFFSETOF(am_mod_cfg_rec, post_dir),
+        RSRC_CONF,
+        "The directory for saving POST requests."
+        " Default value is \"/var/tmp/mellonpost\"."
+        ), 
+    AP_INIT_TAKE1(
+        "MellonPostTTL",
+        am_set_module_config_int_slot,
+        (void *)APR_OFFSETOF(am_mod_cfg_rec, post_ttl),
+        RSRC_CONF,
+        "The time to live for saved POST requests in seconds."
+        " Default value is 15 mn."
+        ), 
+    AP_INIT_TAKE1(
+        "MellonPostCount",
+        am_set_module_config_int_slot,
+        (void *)APR_OFFSETOF(am_mod_cfg_rec, post_count),
+        RSRC_CONF,
+        "The maximum saved POST sessions at once."
+        " Default value is 100."
+        ), 
+    AP_INIT_TAKE1(
+        "MellonPostSize",
+        am_set_module_config_int_slot,
+        (void *)APR_OFFSETOF(am_mod_cfg_rec, post_size),
+        RSRC_CONF,
+        "The maximum size of a saved POST, in bytes."
+        " Default value is 1 MB."
+        ), 
 
 
     /* Per-location configuration directives. */
@@ -870,6 +921,10 @@ void *auth_mellon_server_config(apr_pool_t *p, server_rec *s)
 
     mod->cache_size = 100;  /* ought to be enough for everybody */
     mod->lock_file  = "/tmp/mellonLock";
+    mod->post_dir   = post_dir;
+    mod->post_ttl   = post_ttl;
+    mod->post_count = post_count;
+    mod->post_size  = post_size;
 
     mod->init_cache_size = 0;
     mod->init_lock_file = NULL;
diff --git a/auth_mellon_handler.c b/auth_mellon_handler.c
index b8bc25c..c9b4af4 100644
--- a/auth_mellon_handler.c
+++ b/auth_mellon_handler.c
@@ -30,43 +30,6 @@
 #endif /* HAVE_lasso_server_new_from_buffers */
 
 
-/* This function produces the endpoint URL
- *
- * Parameters:
- *  request_rec *r       The request we received.
- *
- * Returns:
- *  the endpoint URL
- */
-static char *am_get_endpoint_url(request_rec *r)
-{
-    static APR_OPTIONAL_FN_TYPE(ssl_is_https) *am_is_https = NULL;
-    am_dir_cfg_rec *cfg = am_get_dir_cfg(r);
-    apr_pool_t *p = r->pool;
-    server_rec *s = r->server;
-    apr_port_t default_port;
-    char *port;
-    char *scheme;
-
-    am_is_https = APR_RETRIEVE_OPTIONAL_FN(ssl_is_https);
-
-    if (am_is_https && am_is_https(r->connection)) {
-        scheme = "https://";
-        default_port = DEFAULT_HTTPS_PORT;
-    } else {
-        scheme = "http://";
-        default_port = DEFAULT_HTTP_PORT;
-    }
-
-    if (s->addrs->host_port != default_port)
-        port = apr_psprintf(p, ":%d", s->addrs->host_port);
-    else
-        port = "";
-
-    return apr_psprintf(p, "%s%s%s%s", scheme,
-                        s->server_hostname,
-                        port,  cfg->endpoint_path);
-}
 
 #ifdef HAVE_lasso_server_new_from_buffers
 /* This function generates optional metadata for a given element
@@ -1730,6 +1693,129 @@ static int am_handle_artifact_reply(request_rec *r)
     return am_handle_reply_common(r, login, relay_state, "");
 }
 
+/* This function handles responses to repost request
+ *
+ * Parameters:
+ *  request_rec *r       The request we received.
+ *
+ * Returns:
+ *  OK on success, or an error on failure.
+ */
+static int am_handle_repost(request_rec *r)
+{
+    am_mod_cfg_rec *mod_cfg;
+    const char *query;
+    char *cp;
+    char *psf_id;
+    char *psf_filename;
+    char *post_data;
+    char *post_form;
+    char *output;
+    char *last;
+    char *return_url;
+
+    mod_cfg = am_get_mod_cfg(r->server);
+    query = r->parsed_uri.query;
+    
+    psf_id = am_extract_query_parameter(r->pool, query, "id");
+    if (psf_id == NULL) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                      "Bad repost query: missing id");
+        return HTTP_BAD_REQUEST;
+    }
+
+    /* Check that Id is sane */
+    for (cp = psf_id; *cp; cp++) {
+        if (!apr_isalnum(*cp)) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                          "Bad repost query: invalid id \"%s\"", psf_id);
+            return HTTP_BAD_REQUEST;
+        }
+    }
+    
+    
+    return_url = am_extract_query_parameter(r->pool, query, "ReturnTo");
+    if (return_url == NULL) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                      "Invalid or missing query ReturnTo parameter.");
+        return HTTP_BAD_REQUEST;
+    }
+
+    if (am_urldecode(return_url) != OK) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "Bad repost query: return");
+        return HTTP_BAD_REQUEST;
+    }
+
+    psf_filename = apr_psprintf(r->pool, "%s/%s", mod_cfg->post_dir, psf_id); 
+    if ((post_data = am_getfile(r->pool, r->server, psf_filename)) == NULL) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                      "Bad repost query: cannot find \"%s\"", psf_filename);
+        return HTTP_BAD_REQUEST;
+    }
+
+    post_form = "";
+    for (cp = apr_strtok(post_data, "&", &last); cp; 
+         cp = apr_strtok(NULL, "&", &last)) {
+        char *item;
+        char *last2;
+        char *name;
+        char *value;
+        char *input_item;
+
+        item = apr_pstrdup(r->pool, cp);
+
+        name = apr_strtok(item, "=", &last2);  
+        value = apr_strtok(NULL, "=", &last2);
+
+        if (name == NULL)
+            continue;
+
+        if (value == NULL)
+            value = (char *)"";
+
+        if (am_urldecode(name) != OK) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                         "urldecode(\"%s\") failed", name);
+            return HTTP_INTERNAL_SERVER_ERROR;
+        }
+
+        if (am_urldecode(value) != OK) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                         "urldecode(\"%s\") failed", value);
+            return HTTP_INTERNAL_SERVER_ERROR;
+        }
+
+        input_item = apr_psprintf(r->pool, 
+                    "    <input type=\"hidden\" name=\"%s\" value=\"%s\">\n",
+                    am_htmlencode(r, name), am_htmlencode(r, value));
+        post_form = apr_pstrcat(r->pool, post_form, input_item, NULL);
+    }
+    
+    r->content_type = "text/html";
+    output = apr_psprintf(r->pool,
+      "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\n"
+      "<html>\n"
+      " <head>\n" 
+      "  <title>SAML rePOST request</title>\n" 
+      " </head>\n" 
+      " <body onload=\"document.getElementById('form').submit();\">\n" 
+      "  <noscript>\n"
+      "   Your browser does not support Javascript, \n"
+      "   you must click the button below to proceed.\n"
+      "  </noscript>\n"
+      "   <form id=\"form\" method=\"POST\" action=\"%s\">\n%s"
+      "    <noscript>\n"
+      "     <input type=\"submit\">\n"
+      "    </noscript>\n"
+      "   </form>\n"
+      " </body>\n" 
+      "</html>\n",
+      return_url, post_form);
+
+    ap_rputs(output, r);
+    return OK;
+}
+
 
 /* This function handles responses to metadata request
  *
@@ -1739,14 +1825,46 @@ static int am_handle_artifact_reply(request_rec *r)
  * Returns:
  *  OK on success, or an error on failure.
  */
-int am_handle_metadata(request_rec *r)
+static int am_handle_metadata(request_rec *r)
 {
     am_dir_cfg_rec *cfg = am_get_dir_cfg(r);
-    const char *endpoint;
 #ifdef HAVE_lasso_server_new_from_buffers
     LassoServer *server;
     const char *data;
+
+    server = am_get_lasso_server(r);
+    if(server == NULL)
+        return HTTP_INTERNAL_SERVER_ERROR;
+
+    data = cfg->sp_metadata_file;
+    if (data == NULL)
+        return HTTP_INTERNAL_SERVER_ERROR;
+
+    r->content_type = "application/samlmetadata+xml";
+
+    ap_rputs(data, r);
+
+    return OK;
+#else  /* ! HAVE_lasso_server_new_from_buffers */
+
+    ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                  "metadata publishing require lasso 2.2.2 or higher");
+    return HTTP_NOT_FOUND;
 #endif
+}
+
+/* This function handles responses to request on our endpoint
+ *
+ * Parameters:
+ *  request_rec *r       The request we received.
+ *
+ * Returns:
+ *  OK on success, or an error on failure.
+ */
+int am_handler(request_rec *r)
+{
+    am_dir_cfg_rec *cfg = am_get_dir_cfg(r);
+    const char *endpoint;
 
     /* Check if this is a request for one of our endpoints. We check if
      * the uri starts with the path set with the MellonEndpointPath
@@ -1755,11 +1873,6 @@ int am_handle_metadata(request_rec *r)
     if(strstr(r->uri, cfg->endpoint_path) != r->uri)
         return DECLINED;
 
-    endpoint = &r->uri[strlen(cfg->endpoint_path)];
-    if (strcmp(endpoint, "metadata") != 0)
-        return DECLINED;
-
-#ifdef HAVE_lasso_server_new_from_buffers
     /* Make sure that this is a GET request. */
     if(r->method_number != M_GET) {
         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
@@ -1779,27 +1892,17 @@ int am_handle_metadata(request_rec *r)
         return DECLINED;
     }
 
-    server = am_get_lasso_server(r);
-    if(server == NULL)
-        return HTTP_INTERNAL_SERVER_ERROR;
-
-    data = cfg->sp_metadata_file;
-    if (data == NULL)
-        return HTTP_INTERNAL_SERVER_ERROR;
-
-    r->content_type = "application/samlmetadata+xml";
-
-    ap_rputs(data, r);
-
-    return OK;
-#else  /* ! HAVE_lasso_server_new_from_buffers */
-    ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
-                  "metadata publishing require lasso 2.2.2 or higher");
-    return HTTP_NOT_FOUND;
-#endif
+    endpoint = &r->uri[strlen(cfg->endpoint_path)];
+    if (strcmp(endpoint, "metadata") == 0)
+        return am_handle_metadata(r);
+    else if (strcmp(endpoint, "repost") == 0)
+        return am_handle_repost(r);
+    else
+        return DECLINED;
 }
 
 
+
 static int am_auth_new_ticket(request_rec *r)
 {
     am_dir_cfg_rec *cfg = am_get_dir_cfg(r);
@@ -1812,6 +1915,12 @@ static int am_auth_new_ticket(request_rec *r)
 
     relay_state = am_reconstruct_url(r);
 
+    /* If this is a POST request, attempt to save it */
+    if (r->method_number == M_POST) {
+        if (am_save_post(r, &relay_state) != OK)
+            return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
     /* Check if IdP discovery is in use and no IdP was selected yet */
     if ((cfg->discovery_url != NULL) && 
         (am_builtin_discovery_timeout(r) == -1) && /* no built-in discovery */
@@ -1965,6 +2074,8 @@ static int am_endpoint_handler(request_rec *r)
         return am_auth_new_ticket(r);
     } else if(!strcmp(endpoint, "metadata")) {
         return OK;
+    } else if(!strcmp(endpoint, "repost")) {
+        return OK;
     } else if(!strcmp(endpoint, "logout")
               || !strcmp(endpoint, "logoutRequest")) {
         /* logoutRequest is included for backwards-compatibility
diff --git a/auth_mellon_util.c b/auth_mellon_util.c
index 8f4e3bb..57dc653 100644
--- a/auth_mellon_util.c
+++ b/auth_mellon_util.c
@@ -587,3 +587,355 @@ char *am_getfile(apr_pool_t *conf, server_rec *s, const char *file)
 
     return data;
 }
+
+/* 
+ * Create a directory for saved POST sessions, check for proper permissions
+ *
+ * Parameters:
+ *   request_rec *r     The current request
+ *
+ * Returns:
+ *  OK on success, or HTTP_INTERNAL_SERVER on failure.
+ */
+static int am_postdir_mkdir(request_rec *r)
+{
+    apr_int32_t wanted;
+    apr_finfo_t afi;
+    apr_status_t rv;
+    char buffer[512];
+    am_mod_cfg_rec *mod_cfg;
+    apr_fileperms_t mode;
+    apr_uid_t user;
+    apr_uid_t group;
+    apr_fileperms_t prot;
+
+    mod_cfg = am_get_mod_cfg(r->server);
+
+    mode = APR_FPROT_UREAD|APR_FPROT_UWRITE|APR_FPROT_UEXECUTE;
+    if ((rv = apr_dir_make_recursive(mod_cfg->post_dir, mode, r->pool)) != OK) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                      "cannot create POST directory \"%s\": %s",
+                      mod_cfg->post_dir,
+                      apr_strerror(rv, buffer, sizeof(buffer)));
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    /* 
+     * The directory may have already existed. Check we really own it
+     */
+    wanted = APR_FINFO_USER|APR_FINFO_UPROT|APR_FINFO_GPROT|APR_FINFO_WPROT;
+    if (apr_stat(&afi, mod_cfg->post_dir, wanted, r->pool) == OK) {
+        if (apr_uid_current(&user, &group, r->pool) != OK) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                          "apr_uid_current failed");
+            return HTTP_INTERNAL_SERVER_ERROR;
+        }
+
+        if (afi.user != user) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                          "POST directory \"%s\" must be owned by the same "
+                          "user as the web server is running as.",
+                          mod_cfg->post_dir);
+            return HTTP_INTERNAL_SERVER_ERROR;
+        }
+
+        prot = APR_FPROT_UREAD|APR_FPROT_UWRITE|APR_FPROT_UEXECUTE;
+        if (afi.protection != prot) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                          "Premissions on POST directory \"%s\" must be 0700.",
+                          mod_cfg->post_dir);
+            return HTTP_INTERNAL_SERVER_ERROR;
+        }
+    }
+
+    return OK;
+}
+
+/* 
+ * Purge outdated saved POST requests. If the MellonPostDir directory
+ * does not exist, create it first. 
+ *
+ * Parameters:
+ *   request_rec *r     The current request
+ *
+ * Returns:
+ *  OK on success, or HTTP_INTERNAL_SERVER on failure.
+ */
+int am_postdir_cleanup(request_rec *r)
+{
+    am_mod_cfg_rec *mod_cfg;
+    apr_dir_t *postdir;
+    apr_status_t rv;
+    apr_finfo_t afi;
+    char *fname;
+    int count;
+
+    mod_cfg = am_get_mod_cfg(r->server);
+
+    /*
+     * Open our POST directory or create it. 
+     */
+    if (apr_dir_open(&postdir, mod_cfg->post_dir, r->pool) != OK)
+        return am_postdir_mkdir(r);
+
+    /*
+     * Purge outdated items
+     */
+    count = 0;
+    do {
+        rv = apr_dir_read(&afi, APR_FINFO_NAME|APR_FINFO_CTIME, postdir);
+        if (rv != OK)
+            break;
+
+        /* Skip dot_files */
+        if (afi.name[0] == '.')
+             continue;
+
+        if (afi.ctime + mod_cfg->post_ttl > apr_time_sec(apr_time_now())) {
+            fname = apr_psprintf(r->pool, "%s/%s", mod_cfg->post_dir, afi.name);
+            (void)apr_file_remove(fname , r->pool); 
+        } else {
+            count++;
+        }
+    } while (1 /* CONSTCOND */);
+
+    (void)apr_dir_close(postdir);
+
+    if (count >= mod_cfg->post_count) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                      "Too many saved POST sessions. "
+                      "Increase MellonPostCount directive.");
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    return OK;
+}
+
+/* 
+ * HTML-encode a string
+ *
+ * Parameters:
+ *   request_rec *r     The current request
+ *   const char *str    The string to encode
+ *
+ * Returns:
+ *  The encoded string
+ */
+char *am_htmlencode(request_rec *r, const char *str)
+{
+    const char *cp;
+    char *output;
+    apr_size_t outputlen;
+    int i;
+
+    outputlen = 0;
+    for (cp = str; *cp; cp++) {
+        switch (*cp) {
+        case '&':
+            outputlen += 5;
+            break;
+        case '"':
+            outputlen += 6;
+            break;
+        default:
+            outputlen += 1;
+            break;
+        }
+    }
+
+    i = 0;
+    output = apr_palloc(r->pool, outputlen + 1);
+    for (cp = str; *cp; cp++) {
+        switch (*cp) {
+        case '&':
+            (void)strcpy(&output[i], "&amp;");
+            i += 5;
+            break;
+        case '"':
+            (void)strcpy(&output[i], "&quot;");
+            i += 6;
+            break;
+        default:
+            output[i] = *cp;
+            i += 1;
+            break;
+        }
+    }
+    output[i] = '\0';
+
+    return output;
+}
+
+/* This function produces the endpoint URL
+ *
+ * Parameters:
+ *  request_rec *r       The request we received.
+ *
+ * Returns:
+ *  the endpoint URL
+ */
+char *am_get_endpoint_url(request_rec *r)
+{
+    static APR_OPTIONAL_FN_TYPE(ssl_is_https) *am_is_https = NULL;
+    am_dir_cfg_rec *cfg = am_get_dir_cfg(r);
+    apr_pool_t *p = r->pool;
+    server_rec *s = r->server;
+    apr_port_t default_port;
+    char *port;
+    char *scheme;
+
+    am_is_https = APR_RETRIEVE_OPTIONAL_FN(ssl_is_https);
+
+    if (am_is_https && am_is_https(r->connection)) {
+        scheme = "https://";
+        default_port = DEFAULT_HTTPS_PORT;
+    } else {
+        scheme = "http://";
+        default_port = DEFAULT_HTTP_PORT;
+    }
+
+    if (s->addrs->host_port != default_port)
+        port = apr_psprintf(p, ":%d", s->addrs->host_port);
+    else
+        port = "";
+
+    return apr_psprintf(p, "%s%s%s%s", scheme,
+                        s->server_hostname,
+                        port,  cfg->endpoint_path);
+}
+
+/*
+ * The two functions below extract an HTTP header from the request.
+ *
+ * Parameters:
+ *  request_rec *r           The current request.
+ *
+ * Returns:
+ *  1 if multipart/form-data, 0 otherwise.
+ */
+struct am_get_header_state {
+    request_rec *req;
+    const char *header;
+    const char *value;
+};
+
+static int am_get_header_callback(void *s, const char *key, const char *val)
+{
+    struct am_get_header_state *state;
+
+    state = (struct am_get_header_state *)s;
+
+    if (strcmp(key, state->header) != 0)
+       return 1;
+
+    state->value = val;
+    return 0;
+}
+
+static const char *am_get_header(request_rec *r, const char *header) 
+{
+    struct am_get_header_state state;
+
+    state.req = r;
+    state.header = header;
+    state.value = NULL;
+
+    (void)apr_table_do(am_get_header_callback, &state, r->headers_in, NULL);
+
+    return state.value;
+}
+
+/*
+ * This function saves a POST request for later replay and updates
+ * the return URL.
+ *
+ * Parameters:
+ *  request_rec *r           The current request.
+ *  const char **relay_state The returl URL
+ *
+ * Returns:
+ *  OK on success, HTTP_INTERNAL_SERVER_ERROR otherwise
+ */
+int am_save_post(request_rec *r, const char **relay_state)
+{
+    am_mod_cfg_rec *mod_cfg;
+    const char *content_type;
+    const char *psf_id;
+    char *psf_name;
+    char *post_data;
+    apr_size_t post_data_len;
+    apr_size_t written;
+    apr_file_t *psf;
+
+    if (am_postdir_cleanup(r) != OK)
+        return HTTP_INTERNAL_SERVER_ERROR;
+
+    /* Check Content-Type */
+    content_type = am_get_header(r, "Content-Type");
+    if ((content_type != NULL) &&
+        (strcmp(content_type, "application/x-www-form-urlencoded") !=  0)) {
+        /* 
+         * This is probably "multipart/form-data; boundary=XXXXXXXXXX"
+         * The POST request then contains MIME data. We are not yet
+         * able to manage that, so issue an error 500.
+         */
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                      "Unsupported POST Content-Type \"%s\"", content_type);
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    mod_cfg = am_get_mod_cfg(r->server);
+
+    if ((psf_id = am_generate_session_id(r)) == NULL) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "cannot generate id");
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    psf_name = apr_psprintf(r->pool, "%s/%s", mod_cfg->post_dir, psf_id);
+
+    if (apr_file_open(&psf, psf_name,
+                      APR_WRITE|APR_CREATE|APR_BINARY, 
+                      APR_FPROT_UREAD|APR_FPROT_UWRITE,
+                      r->pool) != OK) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                      "cannot create POST session file");
+        return HTTP_INTERNAL_SERVER_ERROR;
+    } 
+
+    if (am_read_post_data(r, &post_data, &post_data_len) != OK) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "cannot read POST data");
+        (void)apr_file_close(psf);
+        return HTTP_INTERNAL_SERVER_ERROR;
+    } 
+
+    if (post_data_len > mod_cfg->post_size) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, 
+                      "POST data size %" APR_SIZE_T_FMT 
+                      " exceeds maximum %" APR_SIZE_T_FMT ". "
+                      "Increase MellonPostSize directive.",
+                      post_data_len, mod_cfg->post_size);
+        (void)apr_file_close(psf);
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    written = post_data_len;
+    if ((apr_file_write(psf, post_data, &written) != OK) ||
+        (written != post_data_len)) { 
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                          "cannot write to POST session file");
+            (void)apr_file_close(psf);
+            return HTTP_INTERNAL_SERVER_ERROR;
+    } 
+    
+    if (apr_file_close(psf) != OK) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                      "cannot close POST session file");
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    *relay_state = apr_psprintf(r->pool, "%srepost?id=%s&ReturnTo=%s", 
+                                am_get_endpoint_url(r), psf_id,
+                                am_urlencode(r->pool, *relay_state));
+
+    return OK;
+}
diff --git a/mod_auth_mellon.c b/mod_auth_mellon.c
index 809ce5d..b7d8349 100644
--- a/mod_auth_mellon.c
+++ b/mod_auth_mellon.c
@@ -94,7 +94,6 @@ static int am_global_init(apr_pool_t *conf, apr_pool_t *log,
     mod->init_cache_size = mod->cache_size;
     mod->init_lock_file = apr_pstrdup(conf, mod->lock_file);
 
-
     /* find out the memory size of the cache */
     mem_size = sizeof(am_cache_entry_t) * mod->init_cache_size;
 
@@ -195,7 +194,7 @@ static void register_hooks(apr_pool_t *p)
     ap_hook_check_user_id(am_check_uid, NULL, NULL, APR_HOOK_MIDDLE);
     ap_hook_post_config(am_global_init, NULL, NULL, APR_HOOK_MIDDLE);
     ap_hook_child_init(am_child_init, NULL, NULL, APR_HOOK_MIDDLE);
-    ap_hook_handler(am_handle_metadata, NULL, NULL, APR_HOOK_MIDDLE);
+    ap_hook_handler(am_handler, NULL, NULL, APR_HOOK_MIDDLE);
     return;
 }