Make maidag hanlde mailer URLs.

This makes it possible to `deliver' mails to mailers without
explicitly specifying `remote+mailer' mailbox URLs.  In
particular, it is handy for implementing mailing lists using
`prog' mailers (as with Mailman).

* maidag/deliver.c (notify_action): Do nothing if biff_user_name
is empty.
(deliver_to_user): Remove `name' argument.  Allow for auth==NULL.
(is_remote_url): Use case-sensitive comparison.
(is_mailer_url): New function.
(deliver_url): Handle mailer URLs as if they were corresponding
`remote+' mailbox URLs.  This allows to handle mailing lists.
* maidag/lmtp.c (lmtp_groups): New global.
(lmtp_set_privs): New function. Sets primary and
supplementary group privileges.
(maidag_lmtp_server): Call lmtp_set_privs.
* maidag/maidag.c (lmtp_group): Remove.  It is superceded by
lmtp_groups.
(maidag_cfg_param): Allow to specify supplementary groups.
* maidag/maidag.h (lmtp_group): Replace with lmtp_groups.

 2008-10-28  Sergey Poznyakoff  <gray@gnu.org.ua>
 
+	Make maidag hanlde mailer URLs.
+
+	This makes it possible to `deliver' mails to mailers without
+	explicitly specifying `remote+mailer' mailbox URLs.  In
+	particular, it is handy for implementing mailing lists using
+	`prog' mailers (as with Mailman).
+	
+	* maidag/deliver.c (notify_action): Do nothing if biff_user_name
+	is empty.
+	(deliver_to_user): Remove `name' argument.  Allow for auth==NULL.
+	(is_remote_url): Use case-sensitive comparison.
+	(is_mailer_url): New function.
+	(deliver_url): Handle mailer URLs as if they were corresponding
+	`remote+' mailbox URLs.  This allows to handle mailing lists.
+	* maidag/lmtp.c (lmtp_groups): New global.
+	(lmtp_set_privs): New function. Sets primary and
+	supplementary group privileges.
+	(maidag_lmtp_server): Call lmtp_set_privs.
+	* maidag/maidag.c (lmtp_group): Remove.  It is superceded by
+	lmtp_groups.
+	(maidag_cfg_param): Allow to specify supplementary groups.
+	* maidag/maidag.h (lmtp_group): Replace with lmtp_groups.
+	
 	Change mailer creation mechanism.
 	
 	* include/mailutils/mailer.h (mu_mailer_create_from_url): New

@@ -87,7 +87,7 @@ static const char *biff_user_name;
 static int
 notify_action (mu_observer_t obs, size_t type, void *data, void *action_data)
 {
-  if (type == MU_EVT_MESSAGE_APPEND)
+  if (type == MU_EVT_MESSAGE_APPEND && biff_user_name)
     {
       mu_message_qid_t qid = data;
       mu_mailbox_t mbox = mu_observer_get_owner (obs);
@@ -144,7 +144,7 @@ attach_notify (mu_mailbox_t mbox)
 
 int
 deliver_to_user (mu_mailbox_t imbx, mu_mailbox_t mbox, mu_message_t msg,
-		 struct mu_auth_data *auth, const char *name,
+		 struct mu_auth_data *auth,
 		 char **errp)
 {
   int status;
@@ -184,6 +184,7 @@ deliver_to_user (mu_mailbox_t imbx, mu_mailbox_t mbox, mu_message_t msg,
     }
   
 #if defined(USE_MAILBOX_QUOTAS)
+  if (auth)
     {
       mu_off_t n;
       mu_off_t msg_size;
@@ -202,10 +203,11 @@ deliver_to_user (mu_mailbox_t imbx, mu_mailbox_t mbox, mu_message_t msg,
       switch (check_quota (auth, mbsize, &n))
 	{
 	case MQUOTA_EXCEEDED:
-	maidag_error (_("%s: mailbox quota exceeded for this recipient"), name);
+	  maidag_error (_("%s: mailbox quota exceeded for this recipient"),
+			auth->name);
 	  if (errp)
 	    asprintf (errp, "%s: mailbox quota exceeded for this recipient",
-		    name);
+		      auth->name);
 	  exit_code = EX_QUOTA();
 	  failed++;
 	  break;
@@ -225,12 +227,12 @@ deliver_to_user (mu_mailbox_t imbx, mu_mailbox_t mbox, mu_message_t msg,
 	    {
 	      maidag_error (_("%s: message would exceed maximum mailbox size for "
 			      "this recipient"),
-			  name);
+			    auth->name);
 	      if (errp)
 		asprintf (errp,
 			  "%s: message would exceed maximum mailbox size "
 			  "for this recipient",
-			name);
+			  auth->name);
 	      exit_code = EX_QUOTA();
 	      failed++;
 	    }
@@ -271,9 +273,24 @@ is_remote_url (mu_url_t url)
 {
   const char *scheme;
   int rc = mu_url_sget_scheme (url, &scheme);
-  return rc == 0 && strncasecmp (scheme, "remote+", 7) == 0;
+  return rc == 0 && strncmp (scheme, "remote+", 7) == 0;
 }
 
+static int
+is_mailer_url (mu_url_t url)
+{
+  mu_record_t record = NULL;
+  int (*pfn) (mu_mailer_t) = NULL;
+  
+  return mu_registrar_lookup_url (url, MU_FOLDER_ATTRIBUTE_FILE,
+				  &record, NULL) == 0
+         && mu_record_get_mailer (record, &pfn) == 0
+         && pfn;
+}
+
+#define REMOTE_PREFIX "remote+"
+#define REMOTE_PREFIX_LEN (sizeof(REMOTE_PREFIX)-1)
+
 int
 deliver_url (mu_url_t url, mu_mailbox_t imbx, const char *name, char **errp)
 {
@@ -282,9 +299,7 @@ deliver_url (mu_url_t url, mu_mailbox_t imbx, const char *name, char **errp)
   mu_message_t msg;
   int status;
 
-  if (is_remote_url (url))
-    auth = NULL;
-  else
+  if (name)
     {
       auth = mu_get_auth_by_name (name);
       if (!auth)
@@ -292,9 +307,10 @@ deliver_url (mu_url_t url, mu_mailbox_t imbx, const char *name, char **errp)
 	  maidag_error (_("%s: no such user"), name);
 	  if (errp)
 	    asprintf (errp, "%s: no such user", name);
-	  exit_code = EX_UNAVAILABLE;
-	  return EX_UNAVAILABLE;
+	  exit_code = EX_NOUSER;
+	  return EX_NOUSER;
 	}
+
       if (current_uid)
 	auth->change_uid = 0;
   
@@ -314,16 +330,59 @@ deliver_url (mu_url_t url, mu_mailbox_t imbx, const char *name, char **errp)
       return EX_TEMPFAIL;
     }
 
-  if (url)
+  if (!url)
+    {
+      status = mu_url_create (&url, auth->mailbox);
+      if (status)
+	{
+	  maidag_error (_("Cannot create URL for %s: %s"),
+			auth->mailbox, mu_strerror (status));
+	  return exit_code = EX_UNAVAILABLE;
+	}
+      status = mu_url_parse (url);
+      if (status)
+	{
+	  maidag_error (_("Error parsing URL %s: %s"),
+			auth->mailbox, mu_strerror (status));
+	  return exit_code = EX_UNAVAILABLE;
+	}
+    }      
+
+  if (is_mailer_url (url))
+    {
+      const char *scheme;
+      size_t len;
+      char *new_scheme;
+      
+      mu_url_sget_scheme (url, &scheme);
+      len = REMOTE_PREFIX_LEN + strlen (scheme);
+      new_scheme = malloc (len + 1);
+      if (!new_scheme)
+	{
+	  mu_error (_("Not enough memory"));
+	  exit (EX_SOFTWARE);
+	}
+      strcat (strcpy (new_scheme, REMOTE_PREFIX), scheme);
+      status = mu_url_set_scheme (url, new_scheme);
+      free (new_scheme);
+      if (status)
+	{
+	  errno = status;
+	  maidag_error (_("Cannot modify URL %s: %s"),
+			mu_url_to_string (url),
+			mu_strerror (status));
+	  mu_auth_data_free (auth);
+	  return EX_TEMPFAIL;
+	}
+    }
   status = mu_mailbox_create_from_url (&mbox, url);
-  else
-    status = mu_mailbox_create (&mbox, auth->mailbox);
 
   if (status)
     {
       maidag_error (_("Cannot open mailbox %s: %s"),
-		    url ? mu_url_to_string (url): auth->mailbox,
+		    mu_url_to_string (url),
 		    mu_strerror (status));
+      mu_url_destroy (&url);
       mu_auth_data_free (auth);
       return EX_TEMPFAIL;
     }
@@ -335,7 +394,7 @@ deliver_url (mu_url_t url, mu_mailbox_t imbx, const char *name, char **errp)
      will be created */
   if (switch_user_id (auth, 1))
     return EX_TEMPFAIL;
-  status = deliver_to_user (imbx, mbox, msg, auth, name, errp);
+  status = deliver_to_user (imbx, mbox, msg, auth, errp);
   if (switch_user_id (auth, 0))
     return EX_TEMPFAIL;
 
@@ -371,7 +430,18 @@ deliver (mu_mailbox_t imbx, char *dest_id, char **errp)
 	}
       status = mu_url_sget_user (url, &name);
       if (status == MU_ERR_NOENT)
+	{
+	  if (!is_mailer_url (url) && !is_remote_url (url))
+	    {
+	      maidag_error (_("no user name"));
+	      if (errp)
+		asprintf (errp, "no user such");
+	      exit_code = EX_NOUSER;
+	      return EX_NOUSER;
+	    }
+	  else
 	    name = NULL;
+	}
       else if (status)
 	{
 	  maidag_error (_("%s: cannot get user name from url: %s"),

@@ -25,6 +25,7 @@
 #include <signal.h>
 #include <mu_umaxtostr.h>
 
+mu_list_t lmtp_groups;
 static int lmtp_transcript;
 
 void
@@ -572,22 +573,67 @@ lmtp_connection (int fd, struct sockaddr *sa, int salen, void *data,
   return 0;
 }
 
-int
-maidag_lmtp_server ()
+static int
+lmtp_set_privs ()
 {
-  struct group *gr = getgrnam (lmtp_group);
+  gid_t gid;
   
+  if (lmtp_groups)
+    {
+      gid_t *gidset = NULL;
+      size_t size = 0;
+      size_t j = 0;
+      mu_iterator_t itr;
+      int rc;
+
+      mu_list_count (lmtp_groups, &size);
+      gidset = calloc (size, sizeof (gidset[0]));
+      if (!gidset)
+	{
+	  mu_error (_("Not enough memory"));
+	  return EX_UNAVAILABLE;
+	}
+      if (mu_list_get_iterator (lmtp_groups, &itr) == 0)
+	{
+	  for (mu_iterator_first (itr);
+	       !mu_iterator_is_done (itr); mu_iterator_next (itr)) 
+	    mu_iterator_current (itr,
+				 (void **)(gidset + j++));
+	  mu_iterator_destroy (&itr);
+	}
+      gid = gidset[0];
+      rc = setgroups (j, gidset);
+      free (gidset);
+      if (rc)
+	{
+	  mu_error(_("setgroups failed: %s"), mu_strerror (errno));
+	  return EX_UNAVAILABLE;
+	}
+    }
+  else
+    {
+      struct group *gr = getgrnam ("mail");
       if (gr == NULL)
 	{
-      mu_error (_("Error getting mail group"));
+	  mu_error (_("Error getting group `mail'"));
 	  return EX_UNAVAILABLE;
 	}
-  
-  if (setgid (gr->gr_gid) == -1)
+      gid = gr->gr_gid;
+    }
+  if (setgid (gid) == -1)
     {
       mu_error (_("Error setting mail group"));
       return EX_UNAVAILABLE;
     }
+  return 0;
+}
+		
+int
+maidag_lmtp_server ()
+{
+  int rc = lmtp_set_privs ();
+  if (rc)
+    return rc;
 
   if (mu_m_server_mode (server) == MODE_DAEMON)
     {

@@ -48,7 +48,6 @@ int lmtp_mode;
 int url_option;
 char *lmtp_url_string;
 int reuse_lmtp_address = 1;
-char *lmtp_group = "mail";
 
 const char *program_version = "maidag (" PACKAGE_STRING ")";
 static char doc[] =
@@ -256,6 +255,28 @@ cb_debug (mu_debug_t debug, void *data, mu_config_value_t *val)
   return 0;
 }
 
+static int
+cb2_group (mu_debug_t debug, const char *gname, void *data)
+{
+  mu_list_t *plist = data;
+  struct group *group;
+
+  if (!*plist)
+    mu_list_create (plist);
+  group = getgrnam (gname);
+  if (!group)
+    mu_cfg_format_error (debug, MU_DEBUG_ERROR, _("Unknown group: %s"), gname);
+  else
+    mu_list_append (*plist, (void*)group->gr_gid);
+  return 0;
+}
+  
+static int
+cb_group (mu_debug_t debug, void *data, mu_config_value_t *arg)
+{
+  return mu_cfg_string_value_cb (debug, arg, cb2_group, data);
+}
+
 struct mu_cfg_param maidag_cfg_param[] = {
   { "exit-multiple-delivery-success", mu_cfg_bool, &multiple_delivery, 0, NULL,
     N_("In case of multiple delivery, exit with code 0 if at least one "
@@ -298,8 +319,9 @@ struct mu_cfg_param maidag_cfg_param[] = {
 /* LMTP support */
   { "lmtp", mu_cfg_bool, &lmtp_mode, 0, NULL,
     N_("Run in LMTP mode.") },
-  { "group", mu_cfg_string, &lmtp_group, 0, NULL,
-    N_("In LMTP mode, change to this group after startup.") },
+  { "group", mu_cfg_callback, &lmtp_groups, 0, cb_group,
+    N_("In LMTP mode, retain these supplementary groups."),
+    N_("groups: list of string") },
   { "listen", mu_cfg_string, &lmtp_url_string, 0, NULL,
     N_("In LMTP mode, listen on the given URL.  Valid URLs are:\n"
        "   tcp://<address: string>:<port: number> (note that port is "

@@ -126,7 +126,7 @@ extern int lmtp_mode;
 extern int url_option;
 extern char *lmtp_url_string;
 extern int reuse_lmtp_address;
-extern char *lmtp_group;
+extern mu_list_t lmtp_groups;
 extern mu_acl_t maidag_acl;
 
 void close_fds (void);