Attachment 48975 Details for Bug 37890 – Add eavesdrop=true|false to match rules

[patch] Add eavesdrop=true|false to match rules

0001-Do-not-allow-eavedropping-unless-rule-owner-explicit.patch (text/plain), 7.97 KB, created by Cosimo Alfarano on 2011-07-11 07:42:24 UTC

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Creator: Cosimo Alfarano

Created: 2011-07-11 07:42:24 UTC

Size: 7.97 KB

patch

obsolete

>From 5ec2151653dba2c9bf061f76f9026b5c80aeb9fa Mon Sep 17 00:00:00 2001
>From: Cosimo Alfarano <cosimo.alfarano@collabora.co.uk>
>Date: Fri, 1 Jul 2011 15:46:28 +0100
>Subject: [PATCH 1/2] Do not allow eavedropping unless rule owner explicitely
> declare it
>
>Adds "eavesdrop=true" as a match rule, meaning that the owner
>intend to eavedrop.
>Otherwise the owner will receive only broadcasted messages and the ones
>meant to be delivered to it.
>
>Bug: https://bugs.freedesktop.org/show_bug.cgi?id=37890
>Bug-NB: NB#269748
>Origin: vendor, Maemo
>---
> bus/signals.c |   93 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> bus/signals.h |   25 ++++++++++-----
> 2 files changed, 110 insertions(+), 8 deletions(-)
>
>diff --git a/bus/signals.c b/bus/signals.c
>index 62881b5..ce1c2ff 100644
>--- a/bus/signals.c
>+++ b/bus/signals.c
>@@ -215,6 +215,20 @@ match_rule_to_string (BusMatchRule *rule)
>         goto nomem;
>     }
> 
>+  if (rule->flags & BUS_MATCH_CLIENT_IS_EAVESDROPPING)
>+    {
>+      if (_dbus_string_get_length (&str) > 0)
>+        {
>+          if (!_dbus_string_append (&str, ","))
>+            goto nomem;
>+        }
>+
>+      if (!_dbus_string_append_printf (&str, "eavesdrop='%s'",
>+            (rule->flags & BUS_MATCH_CLIENT_IS_EAVESDROPPING) ?
>+            "true" : "false"))
>+        goto nomem;
>+    }
>+
>   if (rule->flags & BUS_MATCH_ARGS)
>     {
>       int i;
>@@ -354,6 +368,16 @@ bus_match_rule_set_destination (BusMatchRule *rule,
>   return TRUE;
> }
> 
>+void
>+bus_match_rule_set_client_is_eavesdropping (BusMatchRule *rule,
>+                                            dbus_bool_t is_eavesdropping)
>+{
>+  if (is_eavesdropping)
>+    rule->flags |= BUS_MATCH_CLIENT_IS_EAVESDROPPING;
>+  else
>+    rule->flags &= ~(BUS_MATCH_CLIENT_IS_EAVESDROPPING);
>+}
>+
> dbus_bool_t
> bus_match_rule_set_path (BusMatchRule *rule,
>                          const char   *path,
>@@ -1030,6 +1054,31 @@ bus_match_rule_parse (DBusConnection   *matches_go_to,
>               goto failed;
>             }
>         }
>+      else if (strcmp (key, "eavesdrop") == 0)
>+        {
>+          /* do not detect "eavesdrop" being used more than once in rule:
>+           * 1) it's not possible, it's only in the flags
>+           * 2) it might be used twice to disable eavesdropping when it's
>+           * automatically added (eg dbus-monitor/bustle) */
>+
>+          /* we accept only "true|false" as possible values */
>+          if ((strcmp (value, "true") == 0))
>+            {
>+              bus_match_rule_set_client_is_eavesdropping (rule, TRUE);
>+            }
>+          else if (strcmp (value, "false") == 0)
>+            {
>+              bus_match_rule_set_client_is_eavesdropping (rule, FALSE);
>+            }
>+          else
>+            {
>+              dbus_set_error (error, DBUS_ERROR_MATCH_RULE_INVALID,
>+                              "'eavesdropper=%s' is invalid, "
>+                              "it should be 'true' or 'false'\n",
>+                              value);
>+              goto failed;
>+            }
>+        }
>       else if (strncmp (key, "arg", 3) == 0)
>         {
>           if (!bus_match_rule_parse_arg_match (rule, key, &tmp_str, error))
>@@ -1352,6 +1401,9 @@ match_rule_equal (BusMatchRule *a,
>       strcmp (a->destination, b->destination) != 0)
>     return FALSE;
> 
>+  /* we already compared the value of flags, and
>+   * BUS_MATCH_CLIENT_IS_EAVESDROPPING does not have another struct member */
>+
>   if (a->flags & BUS_MATCH_ARGS)
>     {
>       int i;
>@@ -1619,6 +1671,7 @@ match_rule_matches (BusMatchRule    *rule,
>                     DBusMessage     *message,
>                     BusMatchFlags    already_matched)
> {
>+  dbus_bool_t wants_to_eavesdrop = FALSE;
>   int flags;
> 
>   /* All features of the match rule are AND'd together,
>@@ -1633,6 +1686,9 @@ match_rule_matches (BusMatchRule    *rule,
>   /* Don't bother re-matching features we've already checked implicitly. */
>   flags = rule->flags & (~already_matched);
> 
>+  if (flags & BUS_MATCH_CLIENT_IS_EAVESDROPPING)
>+    wants_to_eavesdrop = TRUE;
>+
>   if (flags & BUS_MATCH_MESSAGE_TYPE)
>     {
>       _dbus_assert (rule->message_type != DBUS_MESSAGE_TYPE_INVALID);
>@@ -1686,6 +1742,24 @@ match_rule_matches (BusMatchRule    *rule,
>         }
>     }
> 
>+  /* Note: this part is relevant for eavesdropper rules:
>+   * Two cases:
>+   * 1) rule has a destination to be matched
>+   *   (flag BUS_MATCH_DESTINATION present). Rule will match if:
>+   *   - rule->destination matches the addressed_recipient
>+   *   AND
>+   *   - wants_to_eavesdrop=TRUE
>+   *
>+   *   Note: (the case in which addressed_recipient is the actual rule owner
>+   *   is handled elsewere in dispatch.c:bus_dispatch_matches().
>+   *
>+   * 2) rule has no destination. Rule will match if:
>+   *    - message has no specified destination (ie broadcasts)
>+   *      (Note: this will rule out unicast method calls and unicast signals,
>+   *      fixing FDO#269748)
>+   *    OR
>+   *    - wants_to_eavesdrop=TRUE (destination-catch-all situation)
>+   */
>   if (flags & BUS_MATCH_DESTINATION)
>     {
>       const char *destination;
>@@ -1694,6 +1768,12 @@ match_rule_matches (BusMatchRule    *rule,
> 
>       destination = dbus_message_get_destination (message);
>       if (destination == NULL)
>+        /* broadcast, but this rule specified a destination: no match */
>+        return FALSE;
>+
>+      /* rule owner does not intend to eavesdrop: we'll deliver only msgs
>+       * directed to it, NOT MATCHING */
>+      if (!wants_to_eavesdrop)
>         return FALSE;
> 
>       if (addressed_recipient == NULL)
>@@ -1707,6 +1787,19 @@ match_rule_matches (BusMatchRule    *rule,
>           if (!connection_is_primary_owner (addressed_recipient, rule->destination))
>             return FALSE;
>         }
>+    } else { /* no destination in rule */
>+        dbus_bool_t msg_is_broadcast;
>+
>+        _dbus_assert (rule->destination == NULL);
>+
>+        msg_is_broadcast = (dbus_message_get_destination (message) == NULL);
>+
>+        if (!wants_to_eavesdrop && !msg_is_broadcast)
>+          return FALSE;
>+
>+        /* if we are here rule owner intends to eavesdrop
>+         * OR
>+         * message is being broadcasted */
>     }
> 
>   if (flags & BUS_MATCH_PATH)
>diff --git a/bus/signals.h b/bus/signals.h
>index 5b086f0..a71d2e4 100644
>--- a/bus/signals.h
>+++ b/bus/signals.h
>@@ -31,14 +31,15 @@
> 
> typedef enum
> {
>-  BUS_MATCH_MESSAGE_TYPE   = 1 << 0,
>-  BUS_MATCH_INTERFACE      = 1 << 1,
>-  BUS_MATCH_MEMBER         = 1 << 2,
>-  BUS_MATCH_SENDER         = 1 << 3,
>-  BUS_MATCH_DESTINATION    = 1 << 4,
>-  BUS_MATCH_PATH           = 1 << 5,
>-  BUS_MATCH_ARGS           = 1 << 6,
>-  BUS_MATCH_PATH_NAMESPACE = 1 << 7
>+  BUS_MATCH_MESSAGE_TYPE            = 1 << 0,
>+  BUS_MATCH_INTERFACE               = 1 << 1,
>+  BUS_MATCH_MEMBER                  = 1 << 2,
>+  BUS_MATCH_SENDER                  = 1 << 3,
>+  BUS_MATCH_DESTINATION             = 1 << 4,
>+  BUS_MATCH_PATH                    = 1 << 5,
>+  BUS_MATCH_ARGS                    = 1 << 6,
>+  BUS_MATCH_PATH_NAMESPACE          = 1 << 7,
>+  BUS_MATCH_CLIENT_IS_EAVESDROPPING = 1 << 8
> } BusMatchFlags;
> 
> BusMatchRule* bus_match_rule_new   (DBusConnection *matches_go_to);
>@@ -64,6 +65,14 @@ dbus_bool_t bus_match_rule_set_arg          (BusMatchRule     *rule,
>                                              dbus_bool_t       is_path,
>                                              dbus_bool_t       is_namespace);
> 
>+/* Calling this methods a client declares that it is creating a rule which
>+ * needs to eavesdrop (e.g., dbus-monitor), any other created rules not
>+ * setting themselves as eavesdropping won't receive any message not addressed
>+ * to them, when eavedrop is enabled in the policy.  On the other hand, when
>+ * eavedrop is not enabled in policy, this method won't have any effect */
>+void bus_match_rule_set_client_is_eavesdropping (BusMatchRule     *rule,
>+                                                 dbus_bool_t is_eavesdropping);
>+
> BusMatchRule* bus_match_rule_parse (DBusConnection   *matches_go_to,
>                                     const DBusString *rule_text,
>                                     DBusError        *error);
>-- 
>1.7.5.4
>

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Attachments on bug 37890: 48962 | 48963 | 48971 | 48972 | 48975 | 48976 | 49015 | 49076

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