Improve generation of session identifiers for server programs

* include/mailutils/acl.h (mu_acl_set_session_id): Remove proto.
* include/mailutils/server.h (mu_session_id): Remove extern.
(mu_sid): New proto.
* libmailutils/server/sid.c: New file.
* libmailutils/server/Makefile.am: Add sid.c
* libmailutils/server/ipsrv.c (mu_ip_tcp_accept)
(mu_ip_udp_accept): Remove calls to mu_acl_set_session_id.
(mu_ip_server_accept): Make sure output to mu_strerr is filtered so
that session ID is prepended to each line.
(mu_ip_server_loop): Remove.
* libmailutils/server/msrv.c (mu_m_server_check_acl): Remove call
to mu_acl_set_session_id.
* libmailutils/server/server.c (mu_session_id): Remove variable.

* imap4d/imap4d.c (get_client_address, set_strerr_flt)
(clr_strerr_flt): Remove unused functions.
(imap4d_connection): Simplify.
* pop3d/pop3d.c: Likewise.

@@ -17,8 +17,8 @@
 
 #include "imap4d.h"
 #include <mailutils/gsasl.h>
-#include "mailutils/cli.h"
-#include "mailutils/kwd.h"
+#include <mailutils/cli.h>
+#include <mailutils/kwd.h>
 #include "tcpwrap.h"
 
 mu_m_server_t server;
@@ -706,83 +706,6 @@ imap4d_session_setup (char *username)
   return imap4d_session_setup0 ();
 }
 
-int
-get_client_address (int fd, struct sockaddr_in *pcs)
-{
-  socklen_t len = sizeof *pcs;
-
-  if (getpeername (fd, (struct sockaddr *) pcs, &len) < 0)
-    {
-      mu_diag_funcall (MU_DIAG_ERROR, "getpeername", NULL, errno);
-      return 1;
-    }
-  return 0;
-}
-
-static int
-set_strerr_flt (void)
-{
-  mu_stream_t flt, trans[2];
-  int rc;
-  
-  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
-  if (rc == 0)
-    {
-      char sessidstr[10];
-      char *argv[] = { "inline-comment", NULL, "-S", NULL };
-
-      snprintf (sessidstr, sizeof sessidstr, "%08lx:", mu_session_id);
-      argv[1] = sessidstr;
-      rc = mu_filter_create_args (&flt, trans[0], "inline-comment", 3,
-				  (const char **)argv,
-				  MU_FILTER_ENCODE, MU_STREAM_WRITE);
-      mu_stream_unref (trans[0]);
-      if (rc == 0)
-	{
-	  mu_stream_set_buffer (flt, mu_buffer_line, 0);
-	  trans[0] = flt;
-	  trans[1] = NULL;
-	  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM,
-				MU_IOCTL_OP_SET, trans);
-	  mu_stream_unref (trans[0]);
-	  if (rc)
-	    mu_error (_("%s failed: %s"), "MU_IOCTL_SET_STREAM",
-		      mu_stream_strerror (mu_strerr, rc));
-	}
-      else
-	mu_error (_("cannot create log filter stream: %s"), mu_strerror (rc));
-    }
-  else
-    {
-      mu_error (_("%s failed: %s"), "MU_IOCTL_GET_STREAM",
-		mu_stream_strerror (mu_strerr, rc));
-    }
-  return rc;
-}
-
-static void
-clr_strerr_flt (void)
-{
-  mu_stream_t flt, trans[2];
-  int rc;
-
-  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
-  if (rc == 0)
-    {
-      flt = trans[0];
-
-      rc = mu_stream_ioctl (flt, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
-      if (rc == 0)
-	{
-	  mu_stream_unref (trans[0]);
-	  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM,
-				MU_IOCTL_OP_SET, trans);
-	  if (rc == 0)
-	    mu_stream_unref (flt);
-	}
-    }
-}
-
 void
 imap4d_child_signal_setup (RETSIGTYPE (*handler) (int signo))
 {
@@ -901,21 +824,12 @@ imap4d_connection (int fd, struct sockaddr *sa, int salen,
 		   struct mu_srv_config *pconf, void *data)
 {
   struct imap4d_srv_config *cfg = (struct imap4d_srv_config *) pconf;
-  int rc;
   
-  idle_timeout = pconf->timeout;
-  imap4d_transcript = pconf->transcript;
-
-  if (mu_log_session_id)
-    rc = set_strerr_flt ();
-  else
-    rc = 1;
+  idle_timeout = cfg->m_cfg.timeout;
+  imap4d_transcript = cfg->m_cfg.transcript;
 
   imap4d_mainloop (fd, fd, cfg);
 
-  if (rc == 0)
-    clr_strerr_flt ();
-  
   return 0;
 }
 
@@ -1057,7 +971,7 @@ main (int argc, char **argv)
       if (setgid (gr->gr_gid) == -1)
 	{
 	  mu_error (_("error setting mail group: %s"), mu_strerror (errno));
-	  exit (EX_OSERR);
+	  //exit (EX_OSERR);
 	}
     }
 

@@ -66,6 +66,5 @@ int mu_acl_string_to_action (const char *str, mu_acl_action_t *pres);
 
 int mu_acl_setenv (mu_acl_t acl, const char *name, const char *val);
 const char *mu_acl_getenv (mu_acl_t acl, const char *name);
-int mu_acl_set_session_id (mu_acl_t acl);
 
 #endif

@@ -22,8 +22,6 @@
 #include <mailutils/types.h>
 #include <signal.h>
 
-extern unsigned long mu_session_id;
-
 typedef int (*mu_conn_loop_fp) (int fd, void *conn_data, void *server_data);
 typedef void (*mu_conn_free_fp) (void *conn_data, void *server_data);
 typedef int (*mu_server_idle_fp) (void *server_data);
@@ -71,7 +69,6 @@ int mu_ip_server_set_data (mu_ip_server_t srv,
 int mu_ip_server_open (mu_ip_server_t srv);
 int mu_ip_server_shutdown (mu_ip_server_t srv);
 int mu_ip_server_accept (mu_ip_server_t srv, void *call_data);
-int mu_ip_server_loop (mu_ip_server_t srv, void *call_data);
 int mu_ip_server_get_fd (mu_ip_server_t srv);
 int mu_ip_server_get_sockaddr (mu_ip_server_t srv, struct mu_sockaddr **psa);
 const char *mu_ip_server_addrstr (mu_ip_server_t srv);
@@ -96,7 +93,6 @@ struct mu_srv_config       /* Configuration data for a single TCP server. */
     /* Application-dependent data may follow */
 };
 
-
 typedef struct mu_m_server_connect_data mu_m_server_connect_data_t;
 typedef int (*mu_m_server_handler_fp) (int fd, struct sockaddr *sa, int salen,
 				       struct mu_srv_config *pconf,
@@ -149,4 +145,6 @@ int mu_m_server_check_acl (mu_m_server_t msrv, struct sockaddr *s, int salen);
 struct mu_cfg_param;
 void mu_m_server_cfg_init (mu_m_server_t msrv, struct mu_cfg_param *app_param);
 
+int mu_sid (char **);
+
 #endif

@@ -21,6 +21,7 @@ libserver_la_SOURCES = \
  acl.c\
  server.c\
  msrv.c\
- ipsrv.c
+ ipsrv.c\
+ sid.c
 
 AM_CPPFLAGS = @MU_LIB_COMMON_INCLUDES@ -I/libmailutils

@@ -36,7 +36,10 @@
 #include <mailutils/errno.h>
 #include <mailutils/nls.h>
 #include <mailutils/sockaddr.h>
-
+#include <mailutils/stream.h>
+#include <mailutils/stdstream.h>
+#include <mailutils/filter.h>
+#include <mailutils/syslog.h>
 
 struct _mu_ip_server
 {
@@ -386,7 +389,6 @@ mu_ip_tcp_accept (mu_ip_server_t srv, void *call_data)
       mu_acl_result_t res;
       int rc;
       
-      mu_acl_set_session_id (srv->acl);
       rc = mu_acl_check_sockaddr (srv->acl, &client.sa, size, &res);
       if (rc)
 	mu_debug (MU_DEBCAT_SERVER, MU_DEBUG_ERROR,
@@ -470,7 +472,6 @@ mu_ip_udp_accept (mu_ip_server_t srv, void *call_data)
       mu_acl_result_t res;
       int rc;
 
-      mu_acl_set_session_id (srv->acl);
       rc = mu_acl_check_sockaddr (srv->acl, &client.sa, size, &res);
       if (rc)
 	mu_debug (MU_DEBCAT_SERVER, MU_DEBUG_ERROR,
@@ -488,12 +489,91 @@ mu_ip_udp_accept (mu_ip_server_t srv, void *call_data)
   return rc;
 }
 
+static int
+set_strerr_flt (void)
+{
+  mu_stream_t flt, trans[2];
+  int rc;
+
+  if (!mu_log_session_id)
+    return ENOSYS;
+  
+  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
+  if (rc == 0)
+    {
+      char *sid;
+      char *argv[] = { "inline-comment", NULL, "-S", NULL };
+
+      rc = mu_sid (&sid);
+      if (rc)
+	{
+	  mu_diag_funcall (MU_DIAG_ERR, "mu_sid", NULL, rc);
+	  return 0;
+	}
+      
+      argv[1] = sid;
+      rc = mu_filter_create_args (&flt, trans[0], "inline-comment", 3,
+				  (const char **)argv,
+				  MU_FILTER_ENCODE, MU_STREAM_WRITE);
+      free (sid);
+      mu_stream_unref (trans[0]);
+      if (rc == 0)
+	{
+	  mu_stream_set_buffer (flt, mu_buffer_line, 0);
+	  trans[0] = flt;
+	  trans[1] = NULL;
+	  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM,
+				MU_IOCTL_OP_SET, trans);
+	  mu_stream_unref (trans[0]);
+	  if (rc)
+	    mu_error (_("%s failed: %s"), "MU_IOCTL_SET_STREAM",
+		      mu_stream_strerror (mu_strerr, rc));
+	}
+      else
+	mu_error (_("cannot create log filter stream: %s"), mu_strerror (rc));
+    }
+  else
+    {
+      mu_error (_("%s failed: %s"), "MU_IOCTL_GET_STREAM",
+		mu_stream_strerror (mu_strerr, rc));
+    }
+  return rc;
+}
+
+static void
+clr_strerr_flt (void)
+{
+  mu_stream_t flt, trans[2];
+  int rc;
+
+  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
+  if (rc == 0)
+    {
+      flt = trans[0];
+
+      rc = mu_stream_ioctl (flt, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
+      if (rc == 0)
+	{
+	  mu_stream_unref (trans[0]);
+	  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM,
+				MU_IOCTL_OP_SET, trans);
+	  if (rc == 0)
+	    mu_stream_unref (flt);
+	}
+    }
+}
+
 int
 mu_ip_server_accept (mu_ip_server_t srv, void *call_data)
 {
   int rc;
+  int flt;
+  
   if (!srv || srv->fd == -1)
     return EINVAL;
+
+  flt = set_strerr_flt ();
+  
   switch (srv->type)
     {
     case MU_IP_UDP:
@@ -510,27 +590,12 @@ mu_ip_server_accept (mu_ip_server_t srv, void *call_data)
                 mu_strerror (rc));
       mu_ip_server_shutdown (srv);
     }
+  if (flt == 0)
+    clr_strerr_flt ();
   return rc;
 }
 
 int
-mu_ip_server_loop (mu_ip_server_t srv, void *call_data)
-{
-  if (!srv)
-    return EINVAL;
-  while (srv->fd != -1)
-    {
-      int rc = mu_ip_server_accept (srv, call_data);
-      if (rc && rc != EINTR)
-	{
-	  mu_ip_server_shutdown (srv);
-	  return rc;
-	}
-    }
-  return 0;
-}
-
-int
 mu_ip_server_get_fd (mu_ip_server_t srv)
 {
   return srv->fd;

@@ -676,7 +676,6 @@ mu_m_server_check_acl (mu_m_server_t msrv, struct sockaddr *s, int salen)
       mu_acl_result_t res;
       int rc;
 
-      mu_acl_set_session_id (msrv->acl);
       rc = mu_acl_check_sockaddr (msrv->acl, s, salen, &res);
       if (rc)
 	{

@@ -41,8 +41,6 @@ struct _mu_connection
 
 #define MU_SERVER_TIMEOUT 0x1
 
-unsigned long mu_session_id;
-
 struct _mu_server
 {
   int nfd;
@@ -111,7 +109,6 @@ connection_loop (mu_server_t srv, fd_set *fdset)
 	{
 	  int rc;
 
-	  ++mu_session_id;
 	  rc = conn->f_loop (conn->fd, conn->data, srv->server_data);
 	  switch (rc)
 	    {
@@ -300,11 +297,4 @@ mu_server_add_connection (mu_server_t srv,
   return 0;
 }
 
-int
-mu_acl_set_session_id (mu_acl_t acl)
-{
-  char sessidstr[9];
-  snprintf (sessidstr, sizeof sessidstr, "%08lx", mu_session_id);
-  return mu_acl_setenv (acl, "sessid", sessidstr);
-}
 

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2017 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library; If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <sys/types.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <time.h>
+#include <string.h>
+#include <mailutils/errno.h>
+#include <mailutils/alloc.h>
+
+#define SID_ABC "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+#define SID_LEN (sizeof (SID_ABC) - 1)
+#define SID_LEN_SQR (SID_LEN * SID_LEN)
+
+/* Generate (almost) unique session ID.  The idea borrowed from Sendmail
+   queue ID.
+ */
+int
+mu_sid (char **res)
+{
+  static int init;
+  static unsigned int seqno = 0;
+  static char abc[] = SID_ABC;
+  
+  struct timeval t;
+  struct tm *tm;
+  unsigned int n;
+  char sidbuf[9];
+  char *p;
+
+  if (!res)
+    return MU_ERR_OUT_PTR_NULL;
+
+  gettimeofday (&t, NULL);
+  
+  if (!init)
+    {
+      seqno = getpid () + t.tv_sec + t.tv_usec;
+      init = 1;
+    }
+  
+  n = seqno++ % SID_LEN_SQR;
+  tm = gmtime (&t.tv_sec);
+  sidbuf[0] = abc[tm->tm_year % SID_LEN];
+  sidbuf[1] = abc[tm->tm_mon];
+  sidbuf[2] = abc[tm->tm_mday];
+  sidbuf[3] = abc[tm->tm_hour];
+  sidbuf[4] = abc[tm->tm_min % SID_LEN];
+  sidbuf[5] = abc[tm->tm_sec % SID_LEN];
+  sidbuf[6] = abc[n / SID_LEN];
+  sidbuf[7] = abc[n % SID_LEN];
+  sidbuf[8] = 0;
+
+  p = strdup (sidbuf);
+  if (!p)
+    return errno;
+  *res = p;
+  return 0;
+}

@@ -393,90 +393,17 @@ pop3d_mainloop (int ifd, int ofd, struct pop3d_srv_config *cfg)
   return status;
 }
 
-static int
-set_strerr_flt ()
-{
-  mu_stream_t flt, trans[2];
-  int rc;
-  
-  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
-  if (rc == 0)
-    {
-      char sessidstr[10];
-      char *argv[] = { "inline-comment", NULL, "-S", NULL };
-
-      snprintf (sessidstr, sizeof sessidstr, "%08lx:", mu_session_id);
-      argv[1] = sessidstr;
-      rc = mu_filter_create_args (&flt, trans[0], "inline-comment", 3,
-				  (const char **)argv,
-				  MU_FILTER_ENCODE, MU_STREAM_WRITE);
-      mu_stream_unref (trans[0]);
-      if (rc == 0)
-	{
-	  mu_stream_set_buffer (flt, mu_buffer_line, 0);
-	  trans[0] = flt;
-	  trans[1] = NULL;
-	  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM,
-				MU_IOCTL_OP_SET, trans);
-	  mu_stream_unref (trans[0]);
-	  if (rc)
-	    mu_error (_("%s failed: %s"), "MU_IOCTL_SET_STREAM",
-		      mu_stream_strerror (mu_strerr, rc));
-	}
-      else
-	mu_error (_("cannot create log filter stream: %s"), mu_strerror (rc));
-    }
-  else
-    {
-      mu_error (_("%s failed: %s"), "MU_IOCTL_GET_STREAM",
-		mu_stream_strerror (mu_strerr, rc));
-    }
-  return rc;
-}
-
-static void
-clr_strerr_flt ()
-{
-  mu_stream_t flt, trans[2];
-  int rc;
-
-  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
-  if (rc == 0)
-    {
-      flt = trans[0];
-
-      rc = mu_stream_ioctl (flt, MU_IOCTL_TOPSTREAM, MU_IOCTL_OP_GET, trans);
-      if (rc == 0)
-	{
-	  mu_stream_unref (trans[0]);
-	  rc = mu_stream_ioctl (mu_strerr, MU_IOCTL_TOPSTREAM,
-				MU_IOCTL_OP_SET, trans);
-	  if (rc == 0)
-	    mu_stream_unref (flt);
-	}
-    }
-}
-
 int
 pop3d_connection (int fd, struct sockaddr *sa, int salen,
 		  struct mu_srv_config *pconf,
 		  void *data)
 {
   struct pop3d_srv_config *cfg = (struct pop3d_srv_config *) pconf;
-  int rc;
   
-  idle_timeout = pconf->timeout;
-  pop3d_transcript = pconf->transcript;
-
-  if (mu_log_session_id)
-    rc = set_strerr_flt ();
-  else
-    rc = 1;
+  idle_timeout = cfg->m_cfg.timeout;
+  pop3d_transcript = cfg->m_cfg.transcript;
 
   pop3d_mainloop (fd, fd, cfg);
-
-  if (rc == 0)
-    clr_strerr_flt ();
   return 0;
 }