hal_rpc_logout_all(), hal_rpc_is_logged_in().

5 files changed, 75 insertions, 7 deletions

diff --git a/hal.h b/hal.h
index 36b69dc..bf5ca6f 100644
--- a/hal.h
+++ b/hal.h
@@ -124,6 +124,7 @@
   DEFINE_HAL_ERROR(HAL_ERROR_NO_KEY_SLOTS_AVAILABLE,    "No key slots available")                       \
   DEFINE_HAL_ERROR(HAL_ERROR_PIN_INCORRECT,             "PIN incorrect")                                \
   DEFINE_HAL_ERROR(HAL_ERROR_NO_CLIENT_SLOTS_AVAILABLE, "No client slots available")                    \
+  DEFINE_HAL_ERROR(HAL_ERROR_FORBIDDEN,                 "Forbidden")                                    \
   END_OF_HAL_ERROR_LIST
 
 /* Marker to forestall silly line continuation errors */
@@ -554,6 +555,11 @@ extern hal_error_t hal_rpc_login(const hal_client_handle_t client,
 
 extern hal_error_t hal_rpc_logout(const hal_client_handle_t client);
 
+extern hal_error_t hal_rpc_logout_all(void);
+
+extern hal_error_t hal_rpc_is_logged_in(const hal_client_handle_t client,
+                                        const hal_user_t user);
+
 /*
  * Get random bytes.
  */
diff --git a/hal_internal.h b/hal_internal.h
index 1c6489f..ea760cf 100644
--- a/hal_internal.h
+++ b/hal_internal.h
@@ -95,6 +95,11 @@ typedef struct {
 
   hal_error_t (*logout)(const hal_client_handle_t client);
 
+  hal_error_t (*logout_all)(void);
+
+  hal_error_t (*is_logged_in)(const hal_client_handle_t client,
+                              const hal_user_t user);
+
   hal_error_t (*get_random)(void *buffer, const size_t length);
 
 } hal_rpc_misc_dispatch_t;
diff --git a/rpc_api.c b/rpc_api.c
index 08ba4cd..d0ed25c 100644
--- a/rpc_api.c
+++ b/rpc_api.c
@@ -148,6 +148,19 @@ hal_error_t hal_rpc_logout(const hal_client_handle_t client)
   return misc_dispatch->logout(client);
 }
 
+hal_error_t hal_rpc_logout_all(void)
+{
+  return misc_dispatch->logout_all();
+}
+
+hal_error_t hal_rpc_is_logged_in(const hal_client_handle_t client,
+                                 const hal_user_t user)
+{
+  if (user != HAL_USER_NORMAL && user != HAL_USER_SO && user != HAL_USER_WHEEL)
+    return HAL_ERROR_BAD_ARGUMENTS;
+  return misc_dispatch->is_logged_in(client, user);
+}
+
 hal_error_t hal_rpc_hash_get_digest_length(const hal_digest_algorithm_t alg, size_t *length)
 {
   if (length == NULL)
diff --git a/rpc_client.c b/rpc_client.c
index 1fcc914..3d4fcee 100644
--- a/rpc_client.c
+++ b/rpc_client.c
@@ -54,6 +54,20 @@ static hal_error_t set_pin(const hal_client_handle_t client,
   return HAL_ERROR_IMPOSSIBLE;
 }
 
+/*
+ * We may end up wanting to wrap a client-side cache around the
+ * login()/logout()/logout_all() calls and reimplement is_logged_in()
+ * on the client side using that cache, so that access checks don't
+ * need to cross the RPC boundary.  Then again, we might not, if the
+ * RPC call is fast enough, so implementing all before the RPC would
+ * qualify as premature optimization.  There aren't all that many
+ * things on the client side that would use this anyway, so the whole
+ * question may be moot.
+ *
+ * For now, we leave all of these as plain RPC calls, but we may want
+ * to revisit this if the is_logged_in() call turns into a bottleneck.
+ */
+
 static hal_error_t login(const hal_client_handle_t client,
                          const hal_user_t user,
                          const char * const pin, const size_t pin_len)
@@ -66,6 +80,17 @@ static hal_error_t logout(const hal_client_handle_t client)
   return HAL_ERROR_IMPOSSIBLE;
 }
 
+static hal_error_t logout_all(void)
+{
+  return HAL_ERROR_IMPOSSIBLE;
+}
+
+static hal_error_t is_logged_in(const hal_client_handle_t client,
+                                const hal_user_t user)
+{
+  return HAL_ERROR_IMPOSSIBLE;
+}
+
 static hal_error_t hash_get_digest_len(const hal_digest_algorithm_t alg, size_t *length)
 {
   return HAL_ERROR_IMPOSSIBLE;
@@ -270,7 +295,7 @@ static hal_error_t pkey_mixed_verify(const hal_session_handle_t session,
  */
 
 const hal_rpc_misc_dispatch_t hal_rpc_remote_misc_dispatch = {
-  set_pin, login, logout, get_random
+  set_pin, login, logout, logout_all, is_logged_in, get_random
 };
 
 const hal_rpc_hash_dispatch_t hal_rpc_remote_hash_dispatch = {
diff --git a/rpc_misc.c b/rpc_misc.c
index 695e0df..2a7c610 100644
--- a/rpc_misc.c
+++ b/rpc_misc.c
@@ -64,10 +64,6 @@ static hal_error_t get_random(void *buffer, const size_t length)
  *
  * More interesting question is whether we should ever allow the WHEEL
  * PIN to be changed a second time without toasting the keystore.
- *
- * We also need a function which the rest of the library can use to
- * check current login status for a particular hal_client_t.  Don't
- * know yet whether we need anything else.
  */
 
 #warning PIN code not yet fully implemented
@@ -180,7 +176,7 @@ static hal_error_t login(const hal_client_handle_t client,
 
   client_slot_t *slot = find_handle(client);
 
-  if (slot != NULL && (slot = alloc_slot()) == NULL)
+  if (slot == NULL && (slot = alloc_slot()) == NULL)
     return HAL_ERROR_NO_CLIENT_SLOTS_AVAILABLE;
 
   slot->handle = client;
@@ -189,6 +185,19 @@ static hal_error_t login(const hal_client_handle_t client,
   return HAL_OK;
 }
 
+static hal_error_t is_logged_in(const hal_client_handle_t client,
+                                const hal_user_t user)
+{
+  assert(user == HAL_USER_NORMAL || user == HAL_USER_SO || user == HAL_USER_WHEEL);
+
+  client_slot_t *slot = find_handle(client);
+
+  if (slot == NULL || slot->logged_in != user)
+    return HAL_ERROR_FORBIDDEN;
+
+  return HAL_OK;
+}
+
 static hal_error_t logout(const hal_client_handle_t client)
 {
   client_slot_t *slot = find_handle(client);
@@ -199,8 +208,18 @@ static hal_error_t logout(const hal_client_handle_t client)
   return HAL_OK;
 }
 
+static hal_error_t logout_all(void)
+{
+#if HAL_STATIC_CLIENT_STATE_BLOCKS > 0
+  for (int i = 0; i < sizeof(client_handle)/sizeof(*client_handle); i++)
+    client_handle[i].logged_in = HAL_USER_NONE;
+#endif
+
+  return HAL_OK;
+}
+
 const hal_rpc_misc_dispatch_t hal_rpc_remote_misc_dispatch = {
-  set_pin, login, logout, get_random
+  set_pin, login, logout, logout_all, is_logged_in, get_random
 };
 
 /*