2 This file is part of GNUnet
3 (C) 2003, 2004, 2005, 2006, 2007 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file transport/plugin_transport_smtp.c
23 * @brief Implementation of the SMTP transport service
24 * @author Christian Grothoff
25 * @author Renaldo Ferreira
29 #include "gnunet_util.h"
30 #include "gnunet_directories.h"
31 #include "gnunet_protocols.h"
32 #include "gnunet_transport.h"
33 #include "gnunet_stats_service.h"
39 * The default maximum size of each outbound SMTP message.
41 #define SMTP_MESSAGE_SIZE 65528
43 #define DEBUG_SMTP GNUNET_NO
45 #define FILTER_STRING_SIZE 64
47 /* how long can a line in base64 encoded
48 mime text be? (in characters, excluding "\n") */
49 #define MAX_CHAR_PER_LINE 76
54 * Host-Address in a SMTP network.
60 * Filter line that every sender must include in the E-mails such
61 * that the receiver can effectively filter out the GNUnet traffic
64 char filter[FILTER_STRING_SIZE];
67 * Claimed E-mail address of the sender.
68 * Format is "foo@bar.com" with null termination, padded to be
69 * of a multiple of 8 bytes long.
71 char senderAddress[0];
76 * Encapsulation of a GNUnet message in the SMTP mail body (before
81 GNUNET_MessageHeader header;
84 * What is the identity of the sender (GNUNET_hash of public key)
86 GNUNET_PeerIdentity sender;
90 /* *********** globals ************* */
93 * apis (our advertised API and the core api )
95 static GNUNET_CoreAPIForTransport *coreAPI;
97 static struct GNUNET_GE_Context *ectx;
100 * Thread that listens for inbound messages
102 static struct GNUNET_ThreadHandle *dispatchThread;
105 * Flag to indicate that server has been shut down.
107 static int smtp_shutdown = GNUNET_YES;
110 * Set to the SMTP server hostname (and port) for outgoing messages.
112 static char *smtp_server_name;
114 static char *pipename;
117 * Lock for uses of libesmtp (not thread-safe).
119 static struct GNUNET_Mutex *lock;
122 * Old handler for SIGPIPE (kept to be able to restore).
124 static struct sigaction old_handler;
128 static GNUNET_TransportAPI smtpAPI;
130 static GNUNET_Stats_ServiceAPI *stats;
132 static int stat_bytesReceived;
134 static int stat_bytesSent;
136 static int stat_bytesDropped;
139 * How many e-mails are we allowed to send per hour?
141 static unsigned long long rate_limit;
143 static GNUNET_CronTime last_transmission;
145 /** ******************** Base64 encoding ***********/
148 static char *cvt = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
149 "abcdefghijklmnopqrstuvwxyz" "0123456789+/";
152 * Encode into Base64.
154 * @param data the data to encode
155 * @param len the length of the input
156 * @param output where to write the output (*output should be NULL,
158 * @return the size of the output
161 base64_encode (const char *data, unsigned int len, char **output)
168 /* (*output)[ret++] = '\r'; \*/
170 if ( (ret % MAX_CHAR_PER_LINE) == 0) { \
171 (*output)[ret++] = '\n'; \
174 opt = GNUNET_malloc (2 + (((len * 4 / 3) + 8) * (MAX_CHAR_PER_LINE + 2)) /
176 /* message must start with \r\n for libesmtp */
181 for (i = 0; i < len; ++i)
183 c = (data[i] >> 2) & 0x3f;
184 opt[ret++] = cvt[(int) c];
186 c = (data[i] << 4) & 0x3f;
188 c |= (data[i] >> 4) & 0x0f;
189 opt[ret++] = cvt[(int) c];
193 c = (data[i] << 2) & 0x3f;
195 c |= (data[i] >> 6) & 0x03;
196 opt[ret++] = cvt[(int) c];
202 opt[ret++] = FILLCHAR;
208 opt[ret++] = cvt[(int) c];
213 opt[ret++] = FILLCHAR;
217 opt[ret++] = FILLCHAR;
221 #define cvtfind(a)( (((a) >= 'A')&&((a) <= 'Z'))? (a)-'A'\
222 :(((a)>='a')&&((a)<='z')) ? (a)-'a'+26\
223 :(((a)>='0')&&((a)<='9')) ? (a)-'0'+52\
225 :((a) == '/') ? 63 : -1)
227 * Decode from Base64.
229 * @param data the data to encode
230 * @param len the length of the input
231 * @param output where to write the output (*output should be NULL,
233 * @return the size of the output
236 base64_decode (const char *data, unsigned int len, char **output)
241 unsigned int ret = 0;
243 #define CHECK_CRLF while (data[i] == '\r' || data[i] == '\n') {\
244 GNUNET_GE_LOG(ectx, GNUNET_GE_DEBUG | GNUNET_GE_REQUEST | GNUNET_GE_USER, "ignoring CR/LF\n"); \
246 if (i >= len) goto END; \
249 *output = GNUNET_malloc ((len * 3 / 4) + 8);
251 GNUNET_GE_LOG (ectx, GNUNET_GE_DEBUG | GNUNET_GE_REQUEST | GNUNET_GE_USER,
252 "base64_decode decoding len=%d\n", len);
254 for (i = 0; i < len; ++i)
257 if (data[i] == FILLCHAR)
259 c = (char) cvtfind (data[i]);
262 c1 = (char) cvtfind (data[i]);
263 c = (c << 2) | ((c1 >> 4) & 0x3);
264 (*output)[ret++] = c;
271 c = (char) cvtfind (c);
272 c1 = ((c1 << 4) & 0xf0) | ((c >> 2) & 0xf);
273 (*output)[ret++] = c1;
282 c1 = (char) cvtfind (c1);
283 c = ((c << 6) & 0xc0) | c1;
284 (*output)[ret++] = c;
291 /* ********************* the real stuff ******************* */
293 #define strAUTOncmp(a,b) strncmp(a,b,strlen(b))
296 * Listen to the pipe, decode messages and send to core.
299 listenAndDistribute (void *unused)
302 unsigned int linesize;
308 GNUNET_TransportPacket *coreMP;
312 linesize = ((GNUNET_MAX_BUFFER_SIZE * 4 / 3) + 8) * (MAX_CHAR_PER_LINE + 2) / MAX_CHAR_PER_LINE; /* maximum size of a line supported */
313 line = GNUNET_malloc (linesize + 2); /* 2 bytes for off-by-one errors, just to be safe... */
315 #define READLINE(l,limit) \
316 do { retl = fgets(l, (limit), fdes); \
317 if ( (retl == NULL) || (smtp_shutdown == GNUNET_YES)) {\
320 if (coreAPI->load_monitor != NULL) \
321 GNUNET_network_monitor_notify_transmission(coreAPI->load_monitor, GNUNET_ND_DOWNLOAD, strlen(retl)); \
325 while (smtp_shutdown == GNUNET_NO)
327 fd = OPEN (pipename, O_RDONLY | O_ASYNC);
330 if (smtp_shutdown == GNUNET_NO)
331 GNUNET_thread_sleep (5 * GNUNET_CRON_SECONDS);
334 fdes = fdopen (fd, "r");
335 while (smtp_shutdown == GNUNET_NO)
337 /* skip until end of header */
340 READLINE (line, linesize);
342 while ((line[0] != '\r') && (line[0] != '\n')); /* expect newline */
343 READLINE (line, linesize); /* read base64 encoded message; decode, process */
347 pos = strlen (line) - 1; /* ignore new line */
348 READLINE (&line[pos], linesize - pos); /* read base64 encoded message; decode, process */
349 if ((line[pos] == '\r') || (line[pos] == '\n'))
350 break; /* empty line => end of message! */
352 size = base64_decode (line, pos, &out);
353 if (size < sizeof (SMTPMessage))
355 GNUNET_GE_BREAK (ectx, 0);
360 mp = (SMTPMessage *) & out[size - sizeof (SMTPMessage)];
361 if (ntohs (mp->header.size) != size)
364 GNUNET_GE_WARNING | GNUNET_GE_BULK |
367 ("Received malformed message via %s. Ignored.\n"),
371 GNUNET_GE_DEBUG | GNUNET_GE_REQUEST |
373 "Size returned by base64=%d, in the msg=%d.\n",
374 size, ntohl (mp->size));
380 stats->change (stat_bytesReceived, size);
381 coreMP = GNUNET_malloc (sizeof (GNUNET_TransportPacket));
383 coreMP->size = size - sizeof (SMTPMessage);
384 coreMP->tsession = NULL;
385 coreMP->sender = mp->sender;
388 GNUNET_GE_DEBUG | GNUNET_GE_REQUEST | GNUNET_GE_USER,
389 "SMTP message passed to the core.\n");
392 coreAPI->receive (coreMP);
397 GNUNET_GE_DEBUG | GNUNET_GE_REQUEST | GNUNET_GE_USER,
398 "SMTP message processed.\n");
407 /* *************** API implementation *************** */
410 * Verify that a hello-Message is correct (a node is reachable at that
411 * address). Since the reply will be asynchronous, a method must be
414 * @param hello the hello message to verify
415 * (the signature/crc have been verified before)
416 * @return GNUNET_OK on success, GNUNET_SYSERR on error
419 api_verify_hello (const GNUNET_MessageHello * hello)
421 const EmailAddress *maddr;
423 maddr = (const EmailAddress *) &hello[1];
424 if ((ntohs (hello->header.size) !=
425 sizeof (GNUNET_MessageHello) + ntohs (hello->senderAddressSize)) ||
426 (maddr->senderAddress[ntohs (hello->senderAddressSize) - 1 -
427 FILTER_STRING_SIZE] != '\0'))
429 GNUNET_GE_BREAK (ectx, 0);
430 return GNUNET_SYSERR; /* obviously invalid */
432 if (NULL == strstr (maddr->filter, ": "))
433 return GNUNET_SYSERR;
438 * Create a hello-Message for the current node. The hello is created
439 * without signature and without a timestamp. The GNUnet core will
440 * GNUNET_RSA_sign the message and add an expiration time.
442 * @return hello on success, NULL on error
444 static GNUNET_MessageHello *
447 GNUNET_MessageHello *msg;
452 GNUNET_GC_get_configuration_value_string (coreAPI->cfg,
454 "X-mailer: GNUnet", &filter);
455 if (NULL == strstr (filter, ": "))
458 GNUNET_GE_WARNING | GNUNET_GE_BULK | GNUNET_GE_USER,
459 _("SMTP filter string to invalid, lacks ': '\n"));
460 GNUNET_free (filter);
464 if (strlen (filter) > FILTER_STRING_SIZE)
466 filter[FILTER_STRING_SIZE] = '\0';
468 GNUNET_GE_WARNING | GNUNET_GE_BULK | GNUNET_GE_USER,
469 _("SMTP filter string to long, capped to `%s'\n"),
472 i = (strlen (email) + 8) & (~7); /* make multiple of 8 */
474 GNUNET_malloc (sizeof (GNUNET_MessageHello) + sizeof (EmailAddress) + i);
475 memset (msg, 0, sizeof (GNUNET_MessageHello) + sizeof (EmailAddress) + i);
476 haddr = (EmailAddress *) & msg[1];
477 memset (&haddr->filter[0], 0, FILTER_STRING_SIZE);
478 strcpy (&haddr->filter[0], filter);
479 memcpy (&haddr->senderAddress[0], email, strlen (email) + 1);
480 msg->senderAddressSize = htons (strlen (email) + 1 + sizeof (EmailAddress));
481 msg->protocol = htons (GNUNET_TRANSPORT_PROTOCOL_NUMBER_SMTP);
482 msg->MTU = htonl (smtpAPI.mtu);
483 msg->header.size = htons (GNUNET_sizeof_hello (msg));
484 if (api_verify_hello (msg) == GNUNET_SYSERR)
485 GNUNET_GE_ASSERT (ectx, 0);
486 GNUNET_free (filter);
490 struct GetMessageClosure
498 get_message (void **buf, int *len, void *cls)
500 struct GetMessageClosure *gmc = cls;
508 if (gmc->pos == gmc->esize)
509 return NULL; /* done */
511 gmc->pos = gmc->esize;
516 * Send a message to the specified remote node.
518 * @param tsession the GNUNET_MessageHello identifying the remote node
519 * @param message what to send
520 * @param size the size of the message
521 * @return GNUNET_SYSERR on error, GNUNET_OK on success
524 api_send (GNUNET_TSession * tsession,
525 const void *msg, const unsigned int size, int important)
527 const GNUNET_MessageHello *hello;
528 const EmailAddress *haddr;
533 struct GetMessageClosure gm_cls;
534 smtp_session_t session;
535 smtp_message_t message;
536 smtp_recipient_t recipient;
541 if (smtp_shutdown == GNUNET_YES)
542 return GNUNET_SYSERR;
543 if ((size == 0) || (size > smtpAPI.mtu))
545 GNUNET_GE_BREAK (ectx, 0);
546 return GNUNET_SYSERR;
548 now = GNUNET_get_time ();
549 if ((important != GNUNET_YES) &&
550 ((now - last_transmission) * rate_limit) < GNUNET_CRON_HOURS)
551 return GNUNET_NO; /* rate too high */
552 last_transmission = now;
554 hello = (const GNUNET_MessageHello *) tsession->internal;
556 return GNUNET_SYSERR;
557 GNUNET_mutex_lock (lock);
558 session = smtp_create_session ();
562 GNUNET_GE_ERROR | GNUNET_GE_ADMIN | GNUNET_GE_USER |
564 _("SMTP: `%s' failed: %s.\n"),
565 "smtp_create_session",
566 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
567 GNUNET_mutex_unlock (lock);
568 return GNUNET_SYSERR;
570 if (0 == smtp_set_server (session, smtp_server_name))
573 GNUNET_GE_ERROR | GNUNET_GE_ADMIN | GNUNET_GE_USER |
575 _("SMTP: `%s' failed: %s.\n"),
577 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
578 smtp_destroy_session (session);
579 GNUNET_mutex_unlock (lock);
580 return GNUNET_SYSERR;
582 haddr = (const EmailAddress *) &hello[1];
583 message = smtp_add_message (session);
587 GNUNET_GE_WARNING | GNUNET_GE_ADMIN | GNUNET_GE_USER |
589 _("SMTP: `%s' failed: %s.\n"),
591 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
592 smtp_destroy_session (session);
593 GNUNET_mutex_unlock (lock);
594 return GNUNET_SYSERR;
596 smtp_set_header (message, "To", NULL, haddr->senderAddress);
597 smtp_set_header (message, "From", NULL, email);
599 filter = GNUNET_strdup (haddr->filter);
600 fvalue = strstr (filter, ": ");
601 GNUNET_GE_ASSERT (NULL, NULL != fvalue);
604 if (0 == smtp_set_header (message, filter, fvalue))
607 GNUNET_GE_WARNING | GNUNET_GE_ADMIN | GNUNET_GE_USER |
609 _("SMTP: `%s' failed: %s.\n"),
611 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
612 smtp_destroy_session (session);
613 GNUNET_mutex_unlock (lock);
614 GNUNET_free (filter);
615 return GNUNET_SYSERR;
617 GNUNET_free (filter);
618 m = GNUNET_malloc (size + sizeof (SMTPMessage));
619 memcpy (m, msg, size);
620 mp = (SMTPMessage *) & m[size];
621 mp->header.size = htons (size + sizeof (SMTPMessage));
622 mp->header.type = htons (0);
623 mp->sender = *coreAPI->my_identity;
627 base64_encode (m, size + sizeof (SMTPMessage), &gm_cls.ebody);
629 if (0 == smtp_size_set_estimate (message, gm_cls.esize))
632 GNUNET_GE_WARNING | GNUNET_GE_ADMIN | GNUNET_GE_USER |
634 _("SMTP: `%s' failed: %s.\n"),
635 "smtp_size_set_estimate",
636 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
638 if (0 == smtp_set_messagecb (message, &get_message, &gm_cls))
641 GNUNET_GE_WARNING | GNUNET_GE_ADMIN | GNUNET_GE_USER |
643 _("SMTP: `%s' failed: %s.\n"),
644 "smtp_set_messagecb",
645 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
646 smtp_destroy_session (session);
647 GNUNET_mutex_unlock (lock);
648 GNUNET_free (gm_cls.ebody);
649 return GNUNET_SYSERR;
651 recipient = smtp_add_recipient (message, haddr->senderAddress);
652 if (recipient == NULL)
655 GNUNET_GE_WARNING | GNUNET_GE_ADMIN | GNUNET_GE_USER |
657 _("SMTP: `%s' failed: %s.\n"),
658 "smtp_add_recipient",
659 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
660 smtp_destroy_session (session);
661 GNUNET_mutex_unlock (lock);
662 return GNUNET_SYSERR;
664 if (0 == smtp_start_session (session))
667 GNUNET_GE_WARNING | GNUNET_GE_ADMIN | GNUNET_GE_USER |
669 _("SMTP: `%s' failed: %s.\n"),
670 "smtp_start_session",
671 smtp_strerror (smtp_errno (), ebuf, EBUF_LEN));
672 smtp_destroy_session (session);
673 GNUNET_mutex_unlock (lock);
674 GNUNET_free (gm_cls.ebody);
675 return GNUNET_SYSERR;
678 stats->change (stat_bytesSent, size);
679 if (coreAPI->load_monitor != NULL)
680 GNUNET_network_monitor_notify_transmission (coreAPI->load_monitor,
683 smtp_message_reset_status (message); /* this is needed to plug a 28-byte/message memory leak in libesmtp */
684 smtp_destroy_session (session);
685 GNUNET_mutex_unlock (lock);
686 GNUNET_free (gm_cls.ebody);
691 * Establish a connection to a remote node.
692 * @param helo the hello-Message for the target node
693 * @param tsessionPtr the session handle that is to be set
694 * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
697 api_connect (const GNUNET_MessageHello * hello,
698 GNUNET_TSession ** tsessionPtr, int may_reuse)
700 GNUNET_TSession *tsession;
702 tsession = GNUNET_malloc (sizeof (GNUNET_TSession));
703 tsession->internal = GNUNET_malloc (GNUNET_sizeof_hello (hello));
704 tsession->peer = hello->senderIdentity;
705 memcpy (tsession->internal, hello, GNUNET_sizeof_hello (hello));
706 tsession->ttype = smtpAPI.protocol_number;
707 (*tsessionPtr) = tsession;
712 * Disconnect from a remote node.
714 * @param tsession the session that is closed
715 * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
718 api_disconnect (GNUNET_TSession * tsession)
720 if (tsession != NULL)
722 if (tsession->internal != NULL)
723 GNUNET_free (tsession->internal);
724 GNUNET_free (tsession);
730 * Start the server process to receive inbound traffic.
731 * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
734 api_start_transport_server ()
736 smtp_shutdown = GNUNET_NO;
737 /* initialize SMTP network */
739 GNUNET_thread_create (&listenAndDistribute, NULL, 1024 * 4);
740 if (dispatchThread == NULL)
742 GNUNET_GE_DIE_STRERROR (ectx,
743 GNUNET_GE_ADMIN | GNUNET_GE_BULK |
744 GNUNET_GE_FATAL, "pthread_create");
745 return GNUNET_SYSERR;
751 * Shutdown the server process (stop receiving inbound traffic). Maybe
755 api_stop_transport_server ()
759 smtp_shutdown = GNUNET_YES;
760 GNUNET_thread_stop_sleep (dispatchThread);
761 GNUNET_thread_join (dispatchThread, &unused);
766 * Convert SMTP hello to an IP address (always fails).
769 api_hello_to_address (const GNUNET_MessageHello * hello,
770 void **sa, unsigned int *sa_len)
772 return GNUNET_SYSERR;
779 api_associate (GNUNET_TSession * tsession)
781 return GNUNET_SYSERR; /* SMTP connections can never be associated */
785 * Always succeeds (for now; we should look at adding
786 * frequency limits to SMTP in the future!).
789 api_test_would_try (GNUNET_TSession * tsession, const unsigned int size,
792 return GNUNET_OK; /* we always try... */
796 * The exported method. Makes the core api available via a global and
797 * returns the smtp transport API.
799 GNUNET_TransportAPI *
800 inittransport_smtp (GNUNET_CoreAPIForTransport * core)
804 unsigned long long mtu;
809 if (!GNUNET_GC_have_configuration_value (coreAPI->cfg, "SMTP", "EMAIL"))
812 GNUNET_GE_ERROR | GNUNET_GE_BULK | GNUNET_GE_USER,
814 ("No email-address specified, can not start SMTP transport.\n"));
817 GNUNET_GC_get_configuration_value_number (coreAPI->cfg,
822 SMTP_MESSAGE_SIZE, &mtu);
823 GNUNET_GC_get_configuration_value_number (coreAPI->cfg,
826 0, 0, 1024 * 1024, &rate_limit);
827 stats = coreAPI->service_request ("stats");
831 = stats->create (gettext_noop ("# bytes received via SMTP"));
832 stat_bytesSent = stats->create (gettext_noop ("# bytes sent via SMTP"));
834 = stats->create (gettext_noop ("# bytes dropped by SMTP (outgoing)"));
836 GNUNET_GC_get_configuration_value_filename (coreAPI->cfg,
839 GNUNET_DEFAULT_DAEMON_VAR_DIRECTORY
840 "/smtp-pipe", &pipename);
842 if (0 != mkfifo (pipename, S_IWUSR | S_IRUSR | S_IWGRP | S_IWOTH))
844 GNUNET_GE_LOG_STRERROR (ectx,
845 GNUNET_GE_ADMIN | GNUNET_GE_BULK |
846 GNUNET_GE_FATAL, "mkfifo");
847 GNUNET_free (pipename);
848 coreAPI->service_release (stats);
852 /* we need to allow the mailer program to send us messages;
853 easiest done by giving it write permissions (see Mantis #1142) */
854 if (0 != chmod (pipename, S_IWUSR | S_IRUSR | S_IWGRP | S_IWOTH))
855 GNUNET_GE_LOG_STRERROR (ectx,
856 GNUNET_GE_ADMIN | GNUNET_GE_BULK |
857 GNUNET_GE_WARNING, "chmod");
858 GNUNET_GC_get_configuration_value_string (coreAPI->cfg,
859 "SMTP", "EMAIL", NULL, &email);
860 lock = GNUNET_mutex_create (GNUNET_NO);
861 GNUNET_GC_get_configuration_value_string (coreAPI->cfg,
866 sa.sa_handler = SIG_IGN;
867 sigemptyset (&sa.sa_mask);
869 sigaction (SIGPIPE, &sa, &old_handler);
871 smtpAPI.protocol_number = GNUNET_TRANSPORT_PROTOCOL_NUMBER_SMTP;
872 smtpAPI.mtu = mtu - sizeof (SMTPMessage);
874 smtpAPI.hello_verify = &api_verify_hello;
875 smtpAPI.hello_create = &api_create_hello;
876 smtpAPI.connect = &api_connect;
877 smtpAPI.send = &api_send;
878 smtpAPI.associate = &api_associate;
879 smtpAPI.disconnect = &api_disconnect;
880 smtpAPI.server_start = &api_start_transport_server;
881 smtpAPI.server_stop = &api_stop_transport_server;
882 smtpAPI.hello_to_address = &api_hello_to_address;
883 smtpAPI.send_now_test = &api_test_would_try;
888 donetransport_smtp ()
890 sigaction (SIGPIPE, &old_handler, NULL);
891 GNUNET_free (smtp_server_name);
894 coreAPI->service_release (stats);
897 GNUNET_mutex_destroy (lock);
900 GNUNET_free (pipename);