diff options
Diffstat (limited to 'system/polkit/CVE-2015-4625.patch')
| -rw-r--r-- | system/polkit/CVE-2015-4625.patch | 1008 |
1 files changed, 0 insertions, 1008 deletions
diff --git a/system/polkit/CVE-2015-4625.patch b/system/polkit/CVE-2015-4625.patch deleted file mode 100644 index 4a43fb433..000000000 --- a/system/polkit/CVE-2015-4625.patch +++ /dev/null @@ -1,1008 +0,0 @@ -From ea544ffc18405237ccd95d28d7f45afef49aca17 Mon Sep 17 00:00:00 2001 -From: Colin Walters <walters@redhat.com> -Date: Thu, 4 Jun 2015 12:15:18 -0400 -Subject: CVE-2015-4625: Use unpredictable cookie values, keep them secret -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -Tavis noted that it'd be possible with a 32 bit counter for someone to -cause the cookie to wrap by creating Authentication requests in a -loop. - -Something important to note here is that wrapping of signed integers -is undefined behavior in C, so we definitely want to fix that. All -counter integers used in this patch are unsigned. - -See the comment above `authentication_agent_generate_cookie` for -details, but basically we're now using a cookie of the form: - -``` - <agent serial> - <agent random id> - <session serial> - <session -random id> -``` - -Which has multiple 64 bit counters, plus unpredictable random 128 bit -integer ids (effectively UUIDs, but we're not calling them that -because we don't need to be globally unique. - -We further ensure that the cookies are not visible to other processes -by changing the setuid helper to accept them over standard input. This -means that an attacker would have to guess both ids. - -In any case, the security hole here is better fixed with the other -change to bind user id (uid) of the agent with cookie lookups, making -cookie guessing worthless. - -Nevertheless, I think it's worth doing this change too, for defense in -depth. - -Bug: https://bugs.freedesktop.org/show_bug.cgi?id=90832 -CVE: CVE-2015-4625 -Reported-by: Tavis Ormandy <taviso@google.com> -Reviewed-by: Miloslav Trmač <mitr@redhat.com> -Signed-off-by: Colin Walters <walters@redhat.com> - -diff --git a/src/polkitagent/polkitagenthelper-pam.c b/src/polkitagent/polkitagenthelper-pam.c -index 937386e..19062aa 100644 ---- a/src/polkitagent/polkitagenthelper-pam.c -+++ b/src/polkitagent/polkitagenthelper-pam.c -@@ -65,7 +65,7 @@ main (int argc, char *argv[]) - { - int rc; - const char *user_to_auth; -- const char *cookie; -+ char *cookie = NULL; - struct pam_conv pam_conversation; - pam_handle_t *pam_h; - const void *authed_user; -@@ -97,7 +97,7 @@ main (int argc, char *argv[]) - openlog ("polkit-agent-helper-1", LOG_CONS | LOG_PID, LOG_AUTHPRIV); - - /* check for correct invocation */ -- if (argc != 3) -+ if (!(argc == 2 || argc == 3)) - { - syslog (LOG_NOTICE, "inappropriate use of helper, wrong number of arguments [uid=%d]", getuid ()); - fprintf (stderr, "polkit-agent-helper-1: wrong number of arguments. This incident has been logged.\n"); -@@ -105,7 +105,10 @@ main (int argc, char *argv[]) - } - - user_to_auth = argv[1]; -- cookie = argv[2]; -+ -+ cookie = read_cookie (argc, argv); -+ if (!cookie) -+ goto error; - - if (getuid () != 0) - { -@@ -203,6 +206,8 @@ main (int argc, char *argv[]) - goto error; - } - -+ free (cookie); -+ - #ifdef PAH_DEBUG - fprintf (stderr, "polkit-agent-helper-1: successfully sent D-Bus message to PolicyKit daemon\n"); - #endif /* PAH_DEBUG */ -@@ -212,6 +217,7 @@ main (int argc, char *argv[]) - return 0; - - error: -+ free (cookie); - if (pam_h != NULL) - pam_end (pam_h, rc); - -diff --git a/src/polkitagent/polkitagenthelper-shadow.c b/src/polkitagent/polkitagenthelper-shadow.c -index a4f73ac..e877915 100644 ---- a/src/polkitagent/polkitagenthelper-shadow.c -+++ b/src/polkitagent/polkitagenthelper-shadow.c -@@ -46,7 +46,7 @@ main (int argc, char *argv[]) - { - struct spwd *shadow; - const char *user_to_auth; -- const char *cookie; -+ char *cookie = NULL; - time_t now; - - /* clear the entire environment to avoid attacks with -@@ -67,7 +67,7 @@ main (int argc, char *argv[]) - openlog ("polkit-agent-helper-1", LOG_CONS | LOG_PID, LOG_AUTHPRIV); - - /* check for correct invocation */ -- if (argc != 3) -+ if (!(argc == 2 || argc == 3)) - { - syslog (LOG_NOTICE, "inappropriate use of helper, wrong number of arguments [uid=%d]", getuid ()); - fprintf (stderr, "polkit-agent-helper-1: wrong number of arguments. This incident has been logged.\n"); -@@ -86,7 +86,10 @@ main (int argc, char *argv[]) - } - - user_to_auth = argv[1]; -- cookie = argv[2]; -+ -+ cookie = read_cookie (argc, argv); -+ if (!cookie) -+ goto error; - - #ifdef PAH_DEBUG - fprintf (stderr, "polkit-agent-helper-1: user to auth is '%s'.\n", user_to_auth); -@@ -153,6 +156,8 @@ main (int argc, char *argv[]) - goto error; - } - -+ free (cookie); -+ - #ifdef PAH_DEBUG - fprintf (stderr, "polkit-agent-helper-1: successfully sent D-Bus message to PolicyKit daemon\n"); - #endif /* PAH_DEBUG */ -@@ -162,6 +167,7 @@ main (int argc, char *argv[]) - return 0; - - error: -+ free (cookie); - fprintf (stdout, "FAILURE\n"); - flush_and_wait (); - return 1; -diff --git a/src/polkitagent/polkitagenthelperprivate.c b/src/polkitagent/polkitagenthelperprivate.c -index cfa77fc..e23f9f5 100644 ---- a/src/polkitagent/polkitagenthelperprivate.c -+++ b/src/polkitagent/polkitagenthelperprivate.c -@@ -23,6 +23,7 @@ - #include "config.h" - #include "polkitagenthelperprivate.h" - #include <stdio.h> -+#include <string.h> - #include <stdlib.h> - #include <unistd.h> - -@@ -45,6 +46,38 @@ _polkit_clearenv (void) - #endif - - -+char * -+read_cookie (int argc, char **argv) -+{ -+ /* As part of CVE-2015-4625, we started passing the cookie -+ * on standard input, to ensure it's not visible to other -+ * processes. However, to ensure that things continue -+ * to work if the setuid binary is upgraded while old -+ * agents are still running (this will be common with -+ * package managers), we support both modes. -+ */ -+ if (argc == 3) -+ return strdup (argv[2]); -+ else -+ { -+ char *ret = NULL; -+ size_t n = 0; -+ ssize_t r = getline (&ret, &n, stdin); -+ if (r == -1) -+ { -+ if (!feof (stdin)) -+ perror ("getline"); -+ free (ret); -+ return NULL; -+ } -+ else -+ { -+ g_strchomp (ret); -+ return ret; -+ } -+ } -+} -+ - gboolean - send_dbus_message (const char *cookie, const char *user) - { -diff --git a/src/polkitagent/polkitagenthelperprivate.h b/src/polkitagent/polkitagenthelperprivate.h -index aeca2c7..547fdcc 100644 ---- a/src/polkitagent/polkitagenthelperprivate.h -+++ b/src/polkitagent/polkitagenthelperprivate.h -@@ -38,6 +38,8 @@ - - int _polkit_clearenv (void); - -+char *read_cookie (int argc, char **argv); -+ - gboolean send_dbus_message (const char *cookie, const char *user); - - void flush_and_wait (); -diff --git a/src/polkitagent/polkitagentsession.c b/src/polkitagent/polkitagentsession.c -index f014773..8b93ad0 100644 ---- a/src/polkitagent/polkitagentsession.c -+++ b/src/polkitagent/polkitagentsession.c -@@ -55,6 +55,7 @@ - #include <stdio.h> - #include <sys/types.h> - #include <sys/wait.h> -+#include <gio/gunixoutputstream.h> - #include <pwd.h> - - #include "polkitagentmarshal.h" -@@ -88,7 +89,7 @@ struct _PolkitAgentSession - gchar *cookie; - PolkitIdentity *identity; - -- int child_stdin; -+ GOutputStream *child_stdin; - int child_stdout; - GPid child_pid; - -@@ -129,7 +130,6 @@ G_DEFINE_TYPE (PolkitAgentSession, polkit_agent_session, G_TYPE_OBJECT); - static void - polkit_agent_session_init (PolkitAgentSession *session) - { -- session->child_stdin = -1; - session->child_stdout = -1; - } - -@@ -395,11 +395,7 @@ kill_helper (PolkitAgentSession *session) - session->child_stdout = -1; - } - -- if (session->child_stdin != -1) -- { -- g_warn_if_fail (close (session->child_stdin) == 0); -- session->child_stdin = -1; -- } -+ g_clear_object (&session->child_stdin); - - session->helper_is_running = FALSE; - -@@ -545,9 +541,9 @@ polkit_agent_session_response (PolkitAgentSession *session, - - add_newline = (response[response_len] != '\n'); - -- write (session->child_stdin, response, response_len); -+ (void) g_output_stream_write_all (session->child_stdin, response, response_len, NULL, NULL, NULL); - if (add_newline) -- write (session->child_stdin, newline, 1); -+ (void) g_output_stream_write_all (session->child_stdin, newline, 1, NULL, NULL, NULL); - } - - /** -@@ -567,8 +563,9 @@ polkit_agent_session_initiate (PolkitAgentSession *session) - { - uid_t uid; - GError *error; -- gchar *helper_argv[4]; -+ gchar *helper_argv[3]; - struct passwd *passwd; -+ int stdin_fd = -1; - - g_return_if_fail (POLKIT_AGENT_IS_SESSION (session)); - -@@ -600,10 +597,8 @@ polkit_agent_session_initiate (PolkitAgentSession *session) - - helper_argv[0] = PACKAGE_PREFIX "/lib/polkit-1/polkit-agent-helper-1"; - helper_argv[1] = passwd->pw_name; -- helper_argv[2] = session->cookie; -- helper_argv[3] = NULL; -+ helper_argv[2] = NULL; - -- session->child_stdin = -1; - session->child_stdout = -1; - - error = NULL; -@@ -615,7 +610,7 @@ polkit_agent_session_initiate (PolkitAgentSession *session) - NULL, - NULL, - &session->child_pid, -- &session->child_stdin, -+ &stdin_fd, - &session->child_stdout, - NULL, - &error)) -@@ -628,6 +623,13 @@ polkit_agent_session_initiate (PolkitAgentSession *session) - if (G_UNLIKELY (_show_debug ())) - g_print ("PolkitAgentSession: spawned helper with pid %d\n", (gint) session->child_pid); - -+ session->child_stdin = (GOutputStream*)g_unix_output_stream_new (stdin_fd, TRUE); -+ -+ /* Write the cookie on stdin so it can't be seen by other processes */ -+ (void) g_output_stream_write_all (session->child_stdin, session->cookie, strlen (session->cookie), -+ NULL, NULL, NULL); -+ (void) g_output_stream_write_all (session->child_stdin, "\n", 1, NULL, NULL, NULL); -+ - session->child_stdout_channel = g_io_channel_unix_new (session->child_stdout); - session->child_stdout_watch_source = g_io_create_watch (session->child_stdout_channel, - G_IO_IN | G_IO_ERR | G_IO_HUP); -diff --git a/src/polkitbackend/polkitbackendinteractiveauthority.c b/src/polkitbackend/polkitbackendinteractiveauthority.c -index 3f339e9..15adc6a 100644 ---- a/src/polkitbackend/polkitbackendinteractiveauthority.c -+++ b/src/polkitbackend/polkitbackendinteractiveauthority.c -@@ -214,6 +214,8 @@ typedef struct - - GDBusConnection *system_bus_connection; - guint name_owner_changed_signal_id; -+ -+ guint64 agent_serial; - } PolkitBackendInteractiveAuthorityPrivate; - - /* ---------------------------------------------------------------------------------------------------- */ -@@ -439,11 +441,15 @@ struct AuthenticationAgent - volatile gint ref_count; - - PolkitSubject *scope; -+ guint64 serial; - - gchar *locale; - GVariant *registration_options; - gchar *object_path; - gchar *unique_system_bus_name; -+ GRand *cookie_pool; -+ gchar *cookie_prefix; -+ guint64 cookie_serial; - - GDBusProxy *proxy; - -@@ -1427,9 +1433,54 @@ authentication_session_cancelled_cb (GCancellable *cancellable, - authentication_session_cancel (session); - } - -+/* We're not calling this a UUID, but it's basically -+ * the same thing, just not formatted that way because: -+ * -+ * - I'm too lazy to do it -+ * - If we did, people might think it was actually -+ * generated from /dev/random, which we're not doing -+ * because this value doesn't actually need to be -+ * globally unique. -+ */ -+static void -+append_rand_u128_str (GString *buf, -+ GRand *pool) -+{ -+ g_string_append_printf (buf, "%08x%08x%08x%08x", -+ g_rand_int (pool), -+ g_rand_int (pool), -+ g_rand_int (pool), -+ g_rand_int (pool)); -+} -+ -+/* A value that should be unique to the (AuthenticationAgent, AuthenticationSession) -+ * pair, and not guessable by other agents. -+ * -+ * <agent serial> - <agent uuid> - <session serial> - <session uuid> -+ * -+ * See http://lists.freedesktop.org/archives/polkit-devel/2015-June/000425.html -+ * -+ */ -+static gchar * -+authentication_agent_generate_cookie (AuthenticationAgent *agent) -+{ -+ GString *buf = g_string_new (""); -+ -+ g_string_append (buf, agent->cookie_prefix); -+ -+ g_string_append_c (buf, '-'); -+ agent->cookie_serial++; -+ g_string_append_printf (buf, "%" G_GUINT64_FORMAT, -+ agent->cookie_serial); -+ g_string_append_c (buf, '-'); -+ append_rand_u128_str (buf, agent->cookie_pool); -+ -+ return g_string_free (buf, FALSE); -+} -+ -+ - static AuthenticationSession * - authentication_session_new (AuthenticationAgent *agent, -- const gchar *cookie, - PolkitSubject *subject, - PolkitIdentity *user_of_subject, - PolkitSubject *caller, -@@ -1447,7 +1498,7 @@ authentication_session_new (AuthenticationAgent *agent, - - session = g_new0 (AuthenticationSession, 1); - session->agent = authentication_agent_ref (agent); -- session->cookie = g_strdup (cookie); -+ session->cookie = authentication_agent_generate_cookie (agent); - session->subject = g_object_ref (subject); - session->user_of_subject = g_object_ref (user_of_subject); - session->caller = g_object_ref (caller); -@@ -1496,16 +1547,6 @@ authentication_session_free (AuthenticationSession *session) - g_free (session); - } - --static gchar * --authentication_agent_new_cookie (AuthenticationAgent *agent) --{ -- static gint counter = 0; -- -- /* TODO: use a more random-looking cookie */ -- -- return g_strdup_printf ("cookie%d", counter++); --} -- - static PolkitSubject * - authentication_agent_get_scope (AuthenticationAgent *agent) - { -@@ -1553,12 +1594,15 @@ authentication_agent_unref (AuthenticationAgent *agent) - g_free (agent->unique_system_bus_name); - if (agent->registration_options != NULL) - g_variant_unref (agent->registration_options); -+ g_rand_free (agent->cookie_pool); -+ g_free (agent->cookie_prefix); - g_free (agent); - } - } - - static AuthenticationAgent * --authentication_agent_new (PolkitSubject *scope, -+authentication_agent_new (guint64 serial, -+ PolkitSubject *scope, - const gchar *unique_system_bus_name, - const gchar *locale, - const gchar *object_path, -@@ -1592,6 +1636,7 @@ authentication_agent_new (PolkitSubject *scope, - - agent = g_new0 (AuthenticationAgent, 1); - agent->ref_count = 1; -+ agent->serial = serial; - agent->scope = g_object_ref (scope); - agent->object_path = g_strdup (object_path); - agent->unique_system_bus_name = g_strdup (unique_system_bus_name); -@@ -1599,6 +1644,25 @@ authentication_agent_new (PolkitSubject *scope, - agent->registration_options = registration_options != NULL ? g_variant_ref (registration_options) : NULL; - agent->proxy = proxy; - -+ { -+ GString *cookie_prefix = g_string_new (""); -+ GRand *agent_private_rand = g_rand_new (); -+ -+ g_string_append_printf (cookie_prefix, "%" G_GUINT64_FORMAT "-", agent->serial); -+ -+ /* Use a uniquely seeded PRNG to get a prefix cookie for this agent, -+ * whose sequence will not correlate with the per-authentication session -+ * cookies. -+ */ -+ append_rand_u128_str (cookie_prefix, agent_private_rand); -+ g_rand_free (agent_private_rand); -+ -+ agent->cookie_prefix = g_string_free (cookie_prefix, FALSE); -+ -+ /* And a newly seeded pool for per-session cookies */ -+ agent->cookie_pool = g_rand_new (); -+ } -+ - return agent; - } - -@@ -2193,7 +2257,6 @@ authentication_agent_initiate_challenge (AuthenticationAgent *agent, - { - PolkitBackendInteractiveAuthorityPrivate *priv = POLKIT_BACKEND_INTERACTIVE_AUTHORITY_GET_PRIVATE (authority); - AuthenticationSession *session; -- gchar *cookie; - GList *l; - GList *identities; - gchar *localized_message; -@@ -2215,8 +2278,6 @@ authentication_agent_initiate_challenge (AuthenticationAgent *agent, - &localized_icon_name, - &localized_details); - -- cookie = authentication_agent_new_cookie (agent); -- - identities = NULL; - - /* select admin user if required by the implicit authorization */ -@@ -2279,7 +2340,6 @@ authentication_agent_initiate_challenge (AuthenticationAgent *agent, - user_identities = g_list_prepend (NULL, polkit_unix_user_new (0)); - - session = authentication_session_new (agent, -- cookie, - subject, - user_of_subject, - caller, -@@ -2335,7 +2395,6 @@ authentication_agent_initiate_challenge (AuthenticationAgent *agent, - g_list_free_full (user_identities, g_object_unref); - g_list_foreach (identities, (GFunc) g_object_unref, NULL); - g_list_free (identities); -- g_free (cookie); - - g_free (localized_message); - g_free (localized_icon_name); -@@ -2482,7 +2541,9 @@ polkit_backend_interactive_authority_register_authentication_agent (PolkitBacken - goto out; - } - -- agent = authentication_agent_new (subject, -+ priv->agent_serial++; -+ agent = authentication_agent_new (priv->agent_serial, -+ subject, - polkit_system_bus_name_get_name (POLKIT_SYSTEM_BUS_NAME (caller)), - locale, - object_path, --- -cgit v0.10.2 - -From 493aa5dc1d278ab9097110c1262f5229bbaf1766 Mon Sep 17 00:00:00 2001 -From: Colin Walters <walters@redhat.com> -Date: Wed, 17 Jun 2015 13:07:02 -0400 -Subject: CVE-2015-4625: Bind use of cookies to specific uids -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -http://lists.freedesktop.org/archives/polkit-devel/2015-June/000425.html - -The "cookie" value that Polkit hands out is global to all polkit -users. And when `AuthenticationAgentResponse` is invoked, we -previously only received the cookie and *target* identity, and -attempted to find an agent from that. - -The problem is that the current cookie is just an integer -counter, and if it overflowed, it would be possible for -an successful authorization in one session to trigger a response -in another session. - -The overflow and ability to guess the cookie were fixed by the -previous patch. - -This patch is conceptually further hardening on top of that. Polkit -currently treats uids as equivalent from a security domain -perspective; there is no support for -SELinux/AppArmor/etc. differentiation. - -We can retrieve the uid from `getuid()` in the setuid helper, which -allows us to ensure the uid invoking `AuthenticationAgentResponse2` -matches that of the agent. - -Then the authority only looks at authentication sessions matching the -cookie that were created by a matching uid, thus removing the ability -for different uids to interfere with each other entirely. - -Several fixes to this patch were contributed by: -Miloslav Trmač <mitr@redhat.com> - -Bug: https://bugs.freedesktop.org/show_bug.cgi?id=90837 -CVE: CVE-2015-4625 -Reported-by: Tavis Ormandy <taviso@google.com> -Reviewed-by: Miloslav Trmač <mitr@redhat.com> -Signed-off-by: Colin Walters <walters@redhat.com> - -diff --git a/data/org.freedesktop.PolicyKit1.AuthenticationAgent.xml b/data/org.freedesktop.PolicyKit1.AuthenticationAgent.xml -index 3b519c2..5beef7d 100644 ---- a/data/org.freedesktop.PolicyKit1.AuthenticationAgent.xml -+++ b/data/org.freedesktop.PolicyKit1.AuthenticationAgent.xml -@@ -8,7 +8,19 @@ - <annotation name="org.gtk.EggDBus.DocString" value="<para>This D-Bus interface is used for communication between the system-wide PolicyKit daemon and one or more authentication agents each running in a user session.</para><para>An authentication agent must implement this interface and register (passing the object path of the object implementing the interface) using the org.freedesktop.PolicyKit1.Authority.RegisterAuthenticationAgent() and org.freedesktop.PolicyKit1.Authority.UnregisterAuthenticationAgent() methods on the #org.freedesktop.PolicyKit1.Authority interface of the PolicyKit daemon.</para>"/> - - <method name="BeginAuthentication"> -- <annotation name="org.gtk.EggDBus.DocString" value="<para>Called by the PolicyKit daemon when the authentication agent needs the user to authenticate as one of the identities in @identities for the action with the identifier @action_id.</para><para>Upon succesful authentication, the authentication agent must invoke the org.freedesktop.PolicyKit1.Authority.AuthenticationAgentResponse() method on the #org.freedesktop.PolicyKit1.Authority interface of the PolicyKit daemon before returning.</para><para>If the user dismisses the authentication dialog, the authentication agent should return an error.</para>"/> -+ <annotation name="org.gtk.EggDBus.DocString" value="<para>Called -+ by the PolicyKit daemon when the authentication agent needs the -+ user to authenticate as one of the identities in @identities for -+ the action with the identifier @action_id.</para><para>This -+ authentication is normally achieved via the -+ polkit_agent_session_response() API, which invokes a private -+ setuid helper process to verify the authentication. When -+ successful, it calls the -+ org.freedesktop.PolicyKit1.Authority.AuthenticationAgentResponse2() -+ method on the #org.freedesktop.PolicyKit1.Authority interface of -+ the PolicyKit daemon before returning. If the user dismisses the -+ authentication dialog, the authentication agent should call -+ polkit_agent_session_cancel().</para>"/> - - <arg name="action_id" direction="in" type="s"> - <annotation name="org.gtk.EggDBus.DocString" value="The identifier for the action that the user is authentication for."/> -diff --git a/data/org.freedesktop.PolicyKit1.Authority.xml b/data/org.freedesktop.PolicyKit1.Authority.xml -index fbfb9cd..f9021ee 100644 ---- a/data/org.freedesktop.PolicyKit1.Authority.xml -+++ b/data/org.freedesktop.PolicyKit1.Authority.xml -@@ -313,7 +313,29 @@ - </method> - - <method name="AuthenticationAgentResponse"> -- <annotation name="org.gtk.EggDBus.DocString" value="Method for authentication agents to invoke on successful authentication. This method will fail unless a sufficiently privileged caller invokes it."/> -+ <annotation name="org.gtk.EggDBus.DocString" value="Method for authentication agents to invoke on successful -+authentication, intended only for use by a privileged helper process -+internal to polkit."/> -+ -+ <arg name="cookie" direction="in" type="s"> -+ <annotation name="org.gtk.EggDBus.DocString" value="The cookie identifying the authentication request that was passed to the authentication agent."/> -+ </arg> -+ -+ <arg name="identity" direction="in" type="(sa{sv})"> -+ <annotation name="org.gtk.EggDBus.Type" value="Identity"/> -+ <annotation name="org.gtk.EggDBus.DocString" value="A #Identity struct describing what identity was authenticated."/> -+ </arg> -+ </method> -+ -+ <method name="AuthenticationAgentResponse2"> -+ <annotation name="org.gtk.EggDBus.DocString" value="Method for authentication agents to invoke on successful -+authentication, intended only for use by a privileged helper process -+internal to polkit. Note this method was added in 0.114, and should be preferred over AuthenticationAgentResponse -+as it fixes a security issue."/> -+ -+ <arg name="uid" direction="in" type="u"> -+ <annotation name="org.gtk.EggDBus.DocString" value="The real uid of the agent. Normally set by the setuid helper program."/> -+ </arg> - - <arg name="cookie" direction="in" type="s"> - <annotation name="org.gtk.EggDBus.DocString" value="The cookie identifying the authentication request that was passed to the authentication agent."/> -diff --git a/docs/polkit/docbook-interface-org.freedesktop.PolicyKit1.Authority.xml b/docs/polkit/docbook-interface-org.freedesktop.PolicyKit1.Authority.xml -index 6525e25..e66bf53 100644 ---- a/docs/polkit/docbook-interface-org.freedesktop.PolicyKit1.Authority.xml -+++ b/docs/polkit/docbook-interface-org.freedesktop.PolicyKit1.Authority.xml -@@ -42,6 +42,8 @@ Structure <link linkend="eggdbus-struct-TemporaryAuthorization">TemporaryAuth - IN String object_path) - <link linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.AuthenticationAgentResponse">AuthenticationAgentResponse</link> (IN String cookie, - IN <link linkend="eggdbus-struct-Identity">Identity</link> identity) -+<link linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.AuthenticationAgentResponse">AuthenticationAgentResponse2</link> (IN uint32 uid, IN String cookie, -+ IN <link linkend="eggdbus-struct-Identity">Identity</link> identity) - <link linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.EnumerateTemporaryAuthorizations">EnumerateTemporaryAuthorizations</link> (IN <link linkend="eggdbus-struct-Subject">Subject</link> subject, - OUT Array<<link linkend="eggdbus-struct-TemporaryAuthorization">TemporaryAuthorization</link>> temporary_authorizations) - <link linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.RevokeTemporaryAuthorizations">RevokeTemporaryAuthorizations</link> (IN <link linkend="eggdbus-struct-Subject">Subject</link> subject) -@@ -777,10 +779,52 @@ AuthenticationAgentResponse (IN String cookie, - IN <link linkend="eggdbus-struct-Identity">Identity</link> identity) - </programlisting> - <para> --Method for authentication agents to invoke on successful authentication. This method will fail unless a sufficiently privileged caller invokes it. -+Method for authentication agents to invoke on successful -+authentication, intended only for use by a privileged helper process -+internal to polkit. Deprecated in favor of AuthenticationAgentResponse2. -+ </para> -+<variablelist role="params"> -+ <varlistentry> -+ <term><literal>IN String <parameter>cookie</parameter></literal>:</term> -+ <listitem> -+ <para> -+The cookie identifying the authentication request that was passed to the authentication agent. -+ </para> -+ </listitem> -+ </varlistentry> -+ <varlistentry> -+ <term><literal>IN <link linkend="eggdbus-struct-Identity">Identity</link> <parameter>identity</parameter></literal>:</term> -+ <listitem> -+ <para> -+A <link linkend="eggdbus-struct-Identity">Identity</link> struct describing what identity was authenticated. -+ </para> -+ </listitem> -+ </varlistentry> -+</variablelist> -+ </refsect2> -+ <refsect2 role="function" id="eggdbus-method-org.freedesktop.PolicyKit1.Authority.AuthenticationAgentResponse2"> -+ <title>AuthenticationAgentResponse2 ()</title> -+ <programlisting> -+AuthenticationAgentResponse2 (IN uint32 uid, -+ IN String cookie, -+ IN <link linkend="eggdbus-struct-Identity">Identity</link> identity) -+ </programlisting> -+ <para> -+Method for authentication agents to invoke on successful -+authentication, intended only for use by a privileged helper process -+internal to polkit. Note this method was introduced in 0.114 to fix a security issue. - </para> - <variablelist role="params"> - <varlistentry> -+ <term><literal>IN uint32 <parameter>uid</parameter></literal>:</term> -+ <listitem> -+ <para> -+The user id of the agent; normally this is the owner of the parent pid -+of the process that invoked the internal setuid helper. -+ </para> -+ </listitem> -+ </varlistentry> -+ <varlistentry> - <term><literal>IN String <parameter>cookie</parameter></literal>:</term> - <listitem> - <para> -diff --git a/docs/polkit/overview.xml b/docs/polkit/overview.xml -index 150a7bc..176d2ea 100644 ---- a/docs/polkit/overview.xml -+++ b/docs/polkit/overview.xml -@@ -314,16 +314,18 @@ - <para> - Authentication agents are provided by desktop environments. When - an user session starts, the agent registers with the polkit -- Authority using -- the <link linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.RegisterAuthenticationAgent">RegisterAuthenticationAgent()</link> -+ Authority using the <link -+ linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.RegisterAuthenticationAgent">RegisterAuthenticationAgent()</link> - method. When services are needed, the authority will invoke -- methods on -- the <link linkend="eggdbus-interface-org.freedesktop.PolicyKit1.AuthenticationAgent">org.freedesktop.PolicyKit1.AuthenticationAgent</link> -+ methods on the <link -+ linkend="eggdbus-interface-org.freedesktop.PolicyKit1.AuthenticationAgent">org.freedesktop.PolicyKit1.AuthenticationAgent</link> - D-Bus interface. Once the user is authenticated, (a privileged -- part of) the agent invokes -- the <link linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.AuthenticationAgentResponse">AuthenticationAgentResponse()</link> -- method. Note that the polkit Authority itself does not care -- how the agent authenticates the user. -+ part of) the agent invokes the <link -+ linkend="eggdbus-method-org.freedesktop.PolicyKit1.Authority.AuthenticationAgentResponse">AuthenticationAgentResponse()</link> -+ method. This method should be treated as an internal -+ implementation detail, and callers should use the public shared -+ library API to invoke it, which currently uses a setuid helper -+ program. - </para> - <para> - The <link linkend="ref-authentication-agent-api">libpolkit-agent-1</link> -diff --git a/src/polkit/polkitauthority.c b/src/polkit/polkitauthority.c -index ab6d3cd..6bd684a 100644 ---- a/src/polkit/polkitauthority.c -+++ b/src/polkit/polkitauthority.c -@@ -1492,6 +1492,14 @@ polkit_authority_authentication_agent_response (PolkitAuthority *authority, - gpointer user_data) - { - GVariant *identity_value; -+ /* Note that in reality, this API is only accessible to root, and -+ * only called from the setuid helper `polkit-agent-helper-1`. -+ * -+ * However, because this is currently public API, we avoid -+ * triggering warnings from ABI diff type programs by just grabbing -+ * the real uid of the caller here. -+ */ -+ uid_t uid = getuid (); - - g_return_if_fail (POLKIT_IS_AUTHORITY (authority)); - g_return_if_fail (cookie != NULL); -@@ -1501,8 +1509,9 @@ polkit_authority_authentication_agent_response (PolkitAuthority *authority, - identity_value = polkit_identity_to_gvariant (identity); - g_variant_ref_sink (identity_value); - g_dbus_proxy_call (authority->proxy, -- "AuthenticationAgentResponse", -- g_variant_new ("(s@(sa{sv}))", -+ "AuthenticationAgentResponse2", -+ g_variant_new ("(us@(sa{sv}))", -+ (guint32)uid, - cookie, - identity_value), - G_DBUS_CALL_FLAGS_NONE, -diff --git a/src/polkitbackend/polkitbackendauthority.c b/src/polkitbackend/polkitbackendauthority.c -index 601a974..03a4e84 100644 ---- a/src/polkitbackend/polkitbackendauthority.c -+++ b/src/polkitbackend/polkitbackendauthority.c -@@ -355,6 +355,7 @@ polkit_backend_authority_unregister_authentication_agent (PolkitBackendAuthority - gboolean - polkit_backend_authority_authentication_agent_response (PolkitBackendAuthority *authority, - PolkitSubject *caller, -+ uid_t uid, - const gchar *cookie, - PolkitIdentity *identity, - GError **error) -@@ -373,7 +374,7 @@ polkit_backend_authority_authentication_agent_response (PolkitBackendAuthority - } - else - { -- return klass->authentication_agent_response (authority, caller, cookie, identity, error); -+ return klass->authentication_agent_response (authority, caller, uid, cookie, identity, error); - } - } - -@@ -587,6 +588,11 @@ static const gchar *server_introspection_data = - " <arg type='s' name='cookie' direction='in'/>" - " <arg type='(sa{sv})' name='identity' direction='in'/>" - " </method>" -+ " <method name='AuthenticationAgentResponse2'>" -+ " <arg type='u' name='uid' direction='in'/>" -+ " <arg type='s' name='cookie' direction='in'/>" -+ " <arg type='(sa{sv})' name='identity' direction='in'/>" -+ " </method>" - " <method name='EnumerateTemporaryAuthorizations'>" - " <arg type='(sa{sv})' name='subject' direction='in'/>" - " <arg type='a(ss(sa{sv})tt)' name='temporary_authorizations' direction='out'/>" -@@ -1035,6 +1041,57 @@ server_handle_authentication_agent_response (Server *server, - error = NULL; - if (!polkit_backend_authority_authentication_agent_response (server->authority, - caller, -+ (uid_t)-1, -+ cookie, -+ identity, -+ &error)) -+ { -+ g_dbus_method_invocation_return_gerror (invocation, error); -+ g_error_free (error); -+ goto out; -+ } -+ -+ g_dbus_method_invocation_return_value (invocation, g_variant_new ("()")); -+ -+ out: -+ if (identity != NULL) -+ g_object_unref (identity); -+} -+ -+static void -+server_handle_authentication_agent_response2 (Server *server, -+ GVariant *parameters, -+ PolkitSubject *caller, -+ GDBusMethodInvocation *invocation) -+{ -+ const gchar *cookie; -+ GVariant *identity_gvariant; -+ PolkitIdentity *identity; -+ GError *error; -+ guint32 uid; -+ -+ identity = NULL; -+ -+ g_variant_get (parameters, -+ "(u&s@(sa{sv}))", -+ &uid, -+ &cookie, -+ &identity_gvariant); -+ -+ error = NULL; -+ identity = polkit_identity_new_for_gvariant (identity_gvariant, &error); -+ if (identity == NULL) -+ { -+ g_prefix_error (&error, "Error getting identity: "); -+ g_dbus_method_invocation_return_gerror (invocation, error); -+ g_error_free (error); -+ goto out; -+ } -+ -+ error = NULL; -+ if (!polkit_backend_authority_authentication_agent_response (server->authority, -+ caller, -+ (uid_t)uid, - cookie, - identity, - &error)) -@@ -1222,6 +1279,8 @@ server_handle_method_call (GDBusConnection *connection, - server_handle_unregister_authentication_agent (server, parameters, caller, invocation); - else if (g_strcmp0 (method_name, "AuthenticationAgentResponse") == 0) - server_handle_authentication_agent_response (server, parameters, caller, invocation); -+ else if (g_strcmp0 (method_name, "AuthenticationAgentResponse2") == 0) -+ server_handle_authentication_agent_response2 (server, parameters, caller, invocation); - else if (g_strcmp0 (method_name, "EnumerateTemporaryAuthorizations") == 0) - server_handle_enumerate_temporary_authorizations (server, parameters, caller, invocation); - else if (g_strcmp0 (method_name, "RevokeTemporaryAuthorizations") == 0) -diff --git a/src/polkitbackend/polkitbackendauthority.h b/src/polkitbackend/polkitbackendauthority.h -index f9f7385..88df82e 100644 ---- a/src/polkitbackend/polkitbackendauthority.h -+++ b/src/polkitbackend/polkitbackendauthority.h -@@ -147,6 +147,7 @@ struct _PolkitBackendAuthorityClass - - gboolean (*authentication_agent_response) (PolkitBackendAuthority *authority, - PolkitSubject *caller, -+ uid_t uid, - const gchar *cookie, - PolkitIdentity *identity, - GError **error); -@@ -249,6 +250,7 @@ gboolean polkit_backend_authority_unregister_authentication_agent (PolkitBackend - - gboolean polkit_backend_authority_authentication_agent_response (PolkitBackendAuthority *authority, - PolkitSubject *caller, -+ uid_t uid, - const gchar *cookie, - PolkitIdentity *identity, - GError **error); -diff --git a/src/polkitbackend/polkitbackendinteractiveauthority.c b/src/polkitbackend/polkitbackendinteractiveauthority.c -index 15adc6a..96725f7 100644 ---- a/src/polkitbackend/polkitbackendinteractiveauthority.c -+++ b/src/polkitbackend/polkitbackendinteractiveauthority.c -@@ -108,8 +108,9 @@ static AuthenticationAgent *get_authentication_agent_for_subject (PolkitBackendI - PolkitSubject *subject); - - --static AuthenticationSession *get_authentication_session_for_cookie (PolkitBackendInteractiveAuthority *authority, -- const gchar *cookie); -+static AuthenticationSession *get_authentication_session_for_uid_and_cookie (PolkitBackendInteractiveAuthority *authority, -+ uid_t uid, -+ const gchar *cookie); - - static GList *get_authentication_sessions_initiated_by_system_bus_unique_name (PolkitBackendInteractiveAuthority *authority, - const gchar *system_bus_unique_name); -@@ -169,6 +170,7 @@ static gboolean polkit_backend_interactive_authority_unregister_authentication_a - - static gboolean polkit_backend_interactive_authority_authentication_agent_response (PolkitBackendAuthority *authority, - PolkitSubject *caller, -+ uid_t uid, - const gchar *cookie, - PolkitIdentity *identity, - GError **error); -@@ -440,6 +442,7 @@ struct AuthenticationAgent - { - volatile gint ref_count; - -+ uid_t creator_uid; - PolkitSubject *scope; - guint64 serial; - -@@ -1603,6 +1606,7 @@ authentication_agent_unref (AuthenticationAgent *agent) - static AuthenticationAgent * - authentication_agent_new (guint64 serial, - PolkitSubject *scope, -+ PolkitIdentity *creator, - const gchar *unique_system_bus_name, - const gchar *locale, - const gchar *object_path, -@@ -1611,6 +1615,10 @@ authentication_agent_new (guint64 serial, - { - AuthenticationAgent *agent; - GDBusProxy *proxy; -+ PolkitUnixUser *creator_user; -+ -+ g_assert (POLKIT_IS_UNIX_USER (creator)); -+ creator_user = POLKIT_UNIX_USER (creator); - - if (!g_variant_is_object_path (object_path)) - { -@@ -1638,6 +1646,7 @@ authentication_agent_new (guint64 serial, - agent->ref_count = 1; - agent->serial = serial; - agent->scope = g_object_ref (scope); -+ agent->creator_uid = (uid_t)polkit_unix_user_get_uid (creator_user); - agent->object_path = g_strdup (object_path); - agent->unique_system_bus_name = g_strdup (unique_system_bus_name); - agent->locale = g_strdup (locale); -@@ -1736,8 +1745,9 @@ get_authentication_agent_for_subject (PolkitBackendInteractiveAuthority *authori - } - - static AuthenticationSession * --get_authentication_session_for_cookie (PolkitBackendInteractiveAuthority *authority, -- const gchar *cookie) -+get_authentication_session_for_uid_and_cookie (PolkitBackendInteractiveAuthority *authority, -+ uid_t uid, -+ const gchar *cookie) - { - PolkitBackendInteractiveAuthorityPrivate *priv; - GHashTableIter hash_iter; -@@ -1755,6 +1765,23 @@ get_authentication_session_for_cookie (PolkitBackendInteractiveAuthority *author - { - GList *l; - -+ /* We need to ensure that if somehow we have duplicate cookies -+ * due to wrapping, that the cookie used is matched to the user -+ * who called AuthenticationAgentResponse2. See -+ * http://lists.freedesktop.org/archives/polkit-devel/2015-June/000425.html -+ * -+ * Except if the legacy AuthenticationAgentResponse is invoked, -+ * we don't know the uid and hence use -1. Continue to support -+ * the old behavior for backwards compatibility, although everyone -+ * who is using our own setuid helper will automatically be updated -+ * to the new API. -+ */ -+ if (uid != (uid_t)-1) -+ { -+ if (agent->creator_uid != uid) -+ continue; -+ } -+ - for (l = agent->active_sessions; l != NULL; l = l->next) - { - AuthenticationSession *session = l->data; -@@ -2544,6 +2571,7 @@ polkit_backend_interactive_authority_register_authentication_agent (PolkitBacken - priv->agent_serial++; - agent = authentication_agent_new (priv->agent_serial, - subject, -+ user_of_caller, - polkit_system_bus_name_get_name (POLKIT_SYSTEM_BUS_NAME (caller)), - locale, - object_path, -@@ -2757,6 +2785,7 @@ polkit_backend_interactive_authority_unregister_authentication_agent (PolkitBack - static gboolean - polkit_backend_interactive_authority_authentication_agent_response (PolkitBackendAuthority *authority, - PolkitSubject *caller, -+ uid_t uid, - const gchar *cookie, - PolkitIdentity *identity, - GError **error) -@@ -2799,7 +2828,7 @@ polkit_backend_interactive_authority_authentication_agent_response (PolkitBacken - } - - /* find the authentication session */ -- session = get_authentication_session_for_cookie (interactive_authority, cookie); -+ session = get_authentication_session_for_uid_and_cookie (interactive_authority, uid, cookie); - if (session == NULL) - { - g_set_error (error, --- -cgit v0.10.2 - ---- ./configure.ac.orig -+++ ./configure.ac -@@ -122,7 +122,7 @@ - changequote([,])dnl - fi - --PKG_CHECK_MODULES(GLIB, [gio-2.0 >= 2.28.0]) -+PKG_CHECK_MODULES(GLIB, [gmodule-2.0 gio-unix-2.0 gio-2.0 >= 2.30.0]) - AC_SUBST(GLIB_CFLAGS) - AC_SUBST(GLIB_LIBS) - |