associations robustness improvements and documentation updates

3 files changed, 24 insertions, 1 deletions

diff --git a/include/opkele/association.h b/include/opkele/association.h
index a8f3915..72eff5b 100644
--- a/include/opkele/association.h
+++ b/include/opkele/association.h
@@ -48,21 +48,23 @@ namespace opkele {
              * @param __secret the secret
              * @param __expires expiration time
              * @param __stateless statelessness of the assoc_handle
              */
             association(const string& __server, const string& __handle,
                     const string& __assoc_type, const secret_t& __secret,
                     time_t __expires, bool __stateless)
                 : _server(__server), _handle(__handle), _assoc_type(__assoc_type),
                 _secret(__secret), _expires(__expires), _stateless(__stateless) { }
 
             virtual string server() const { return _server; }
             virtual string handle() const { return _handle; }
             virtual string assoc_type() const { return _assoc_type; }
             virtual secret_t secret() const { return _secret; }
             virtual int expires_in() const { return _expires-time(0); }
             virtual bool stateless() const { return _stateless; }
+
+            virtual bool is_expired() const { return _expires<time(0); }
     };
 
 }
 
 #endif /* __OPKELE_ASSOCIATION_H */
diff --git a/include/opkele/consumer.h b/include/opkele/consumer.h
index 042e2d1..b9d1e54 100644
--- a/include/opkele/consumer.h
+++ b/include/opkele/consumer.h
@@ -1,66 +1,83 @@
 #ifndef __OPKELE_CONSUMER_H
 #define __OPKELE_CONSUMER_H
 
 #include <opkele/types.h>
 #include <opkele/extension.h>
 
 /**
  * @file
  * @brief OpenID consumer-side functionality
  */
 
 namespace opkele {
 
     /**
      * implementation of basic consumer functionality
+     *
+     * @note
+     * The consumer uses libcurl internally, which means that if you're using
+     * libopkele in multithreaded environment you should call curl_global_init
+     * yourself before spawning any threads.
      */
     class consumer_t {
         public:
 
             /**
              * store association. The function should be overridden in the real
              * implementation to provide persistent associations store.
              * @param server the OpenID server
              * @param handle association handle
              * @param secret the secret associated with the server and handle
              * @param expires_in the number of seconds until the handle is expired
              * @return the auto_ptr<> for the newly allocated association_t object
              */
             virtual assoc_t store_assoc(const string& server,const string& handle,const secret_t& secret,int expires_in) = 0;
             /**
              * retrieve stored association. The function should be overridden
              * in the real implementation to provide persistent assocations
              * store.
+             *
+             * @note
+             * The user is responsible for handling associations expiry and
+             * this function should never return an expired or invalidated
+             * association.
+             *
              * @param server the OpenID server
              * @param handle association handle
              * @return the autho_ptr<> for the newly allocated association_t object
-             * @throw failed_lookup in case of error
+             * @throw failed_lookup if no unexpired association found
              */
             virtual assoc_t retrieve_assoc(const string& server,const string& handle) = 0;
             /**
              * invalidate stored association. The function should be overridden
              * in the real implementation of the consumer.
              * @param server the OpenID server
              * @param handle association handle
              */
             virtual void invalidate_assoc(const string& server,const string& handle) = 0;
             /**
              * retrieve any unexpired association for the server. If the
              * function is not overridden in the real implementation, the new
              * association will be established for each request.
+             *
+             * @note
+             * The user is responsible for handling associations and this
+             * function should never return an expired or invalidated
+             * association.
+             *
              * @param server the OpenID server
              * @return the auto_ptr<> for the newly allocated association_t object
              * @throw failed_lookup in case of absence of the handle
              */
             virtual assoc_t find_assoc(const string& server);
 
             /**
              * retrieve the metainformation contained in link tags from the
              * page pointed by url. the function may implement caching of the
              * information.
              * @param url url to harvest for link tags
              * @param server reference to the string object where to put
              * openid.server value
              * @param delegate reference to the string object where to put the
              * openid.delegate value (if any)
              */
diff --git a/lib/consumer.cc b/lib/consumer.cc
index dd8e150..af309c1 100644
--- a/lib/consumer.cc
+++ b/lib/consumer.cc
@@ -131,49 +131,53 @@ namespace opkele {
         params_t p;
         if(mode==mode_checkid_immediate)
             p["mode"]="checkid_immediate";
         else if(mode==mode_checkid_setup)
             p["mode"]="checkid_setup";
         else
             throw bad_input(OPKELE_CP_ "unknown checkid_* mode");
         string iurl = canonicalize(identity);
         string server, delegate;
         retrieve_links(iurl,server,delegate);
         p["identity"] = delegate.empty()?iurl:delegate;
         if(!trust_root.empty())
             p["trust_root"] = trust_root;
         p["return_to"] = return_to;
         try {
             string ah = find_assoc(server)->handle();
+            if(ah->is_expired()) /* TODO: or should I throw some other exception to force programmer fix his implementation? */
+                throw failed_lookup(OPKELE_CP_ "find_assoc() has returned expired handle");
             p["assoc_handle"] = ah;
         }catch(failed_lookup& fl) {
             string ah = associate(server)->handle();
             p["assoc_handle"] = ah;
         }
         if(ext) ext->checkid_hook(p,identity);
         return p.append_query(server);
     }
 
     void consumer_t::id_res(const params_t& pin,const string& identity,extension_t *ext) {
         if(pin.has_param("openid.user_setup_url"))
             throw id_res_setup(OPKELE_CP_ "assertion failed, setup url provided",pin.get_param("openid.user_setup_url"));
         string server,delegate;
         retrieve_links(identity.empty()?pin.get_param("openid.identity"):canonicalize(identity),server,delegate);
         params_t ps;
         try {
             assoc_t assoc = retrieve_assoc(server,pin.get_param("openid.assoc_handle"));
+            if(assoc->is_expired()) /* TODO: or should I throw some other exception to force programmer fix his implementation? */
+                throw failed_lookup(OPKELE_CP_ "retrieve_assoc() has returned expired handle");
             const string& sigenc = pin.get_param("openid.sig");
             vector<unsigned char> sig;
             util::decode_base64(sigenc,sig);
             const string& slist = pin.get_param("openid.signed");
             string kv;
             string::size_type p = 0;
             while(true) {
                 string::size_type co = slist.find(',',p);
                 string f = (co==string::npos)?slist.substr(p):slist.substr(p,co-p);
                 kv += f;
                 kv += ':';
                 f.insert(0,"openid.");
                 kv += pin.get_param(f);
                 kv += '\n';
                 if(ext) ps[f.substr(sizeof("openid.")-1)] = pin.get_param(f);
                 if(co==string::npos)