From 5f5585d519e81237e0c689d113bc36bc0570d7b3 Mon Sep 17 00:00:00 2001
From: SJ <sj@acts.hu>
Date: Sun, 23 Oct 2016 22:04:55 +0200
Subject: [PATCH] first demo of the new architecture

Change-Id: Id76636f30173465fbd0e8516d99017b4336de4db
Signed-off-by: SJ <sj@acts.hu>
---
 configure        |   4 +-
 configure.in     |   2 +-
 src/Makefile.in  |   7 +-
 src/bdat.c       | 136 ++++++++++++++
 src/cfg.c        |   1 +
 src/cfg.h        |   1 +
 src/config.h     |   4 +-
 src/defs.h       |  26 ++-
 src/dirs.c       |   6 +
 src/misc.c       |  27 ++-
 src/misc.h       |   3 +
 src/piler-smtp.c | 472 +++++++++++++++++++++++++++++++++++++++++++++++
 src/piler.c      |  67 +++----
 src/piler.h      |   4 +-
 src/sig.h        |   2 +
 src/smtp.c       | 458 ++++++++++++++++++++++++---------------------
 src/smtp.h       |  30 +--
 src/smtpcodes.h  |   2 +-
 18 files changed, 982 insertions(+), 270 deletions(-)
 create mode 100644 src/bdat.c
 create mode 100644 src/piler-smtp.c

diff --git a/configure b/configure
index 74a295d1..8bee6e37 100755
--- a/configure
+++ b/configure
@@ -4645,7 +4645,7 @@ fi
 
 if test "$os" = "FreeBSD"; then
    defs="$defs -DFREEBSD"
-   antispam_libs="-lz -lm -lcrypto -lssl"
+   antispam_libs="-lz -lm -lcrypto -lssl -liconv"
    MAKE="gmake"
 fi
 
@@ -4866,7 +4866,7 @@ echo; echo
 
 CFLAGS="$static -O2 -Wall -g"
 LIBS="$antispam_libs $sunos_libs "
-OBJS="dirs.o base64.o misc.o counters.o cfg.o sig.o decoder.o hash.o parser.o parser_utils.o rules.o smtp.o session.o message.o attachment.o digest.o store.o archive.o tai.o import.o import_maildir.o import_mailbox.o import_pop3.o import_imap.o import_gui.o imap.o pop3.o extract.o mydomains.o $objs"
+OBJS="dirs.o base64.o misc.o counters.o cfg.o sig.o decoder.o hash.o parser.o parser_utils.o rules.o smtp.o bdat.o message.o attachment.o digest.o store.o archive.o tai.o import.o import_maildir.o import_mailbox.o import_pop3.o import_imap.o import_gui.o imap.o pop3.o extract.o mydomains.o $objs"
 
 ac_config_files="$ac_config_files Makefile src/Makefile etc/Makefile util/Makefile init.d/Makefile unit_tests/Makefile contrib/imap/Makefile"
 
diff --git a/configure.in b/configure.in
index 156f6dbd..000184d5 100644
--- a/configure.in
+++ b/configure.in
@@ -544,7 +544,7 @@ echo; echo
 
 CFLAGS="$static -O2 -Wall -g"
 LIBS="$antispam_libs $sunos_libs "
-OBJS="dirs.o base64.o misc.o counters.o cfg.o sig.o decoder.o hash.o parser.o parser_utils.o rules.o smtp.o session.o message.o attachment.o digest.o store.o archive.o tai.o import.o import_maildir.o import_mailbox.o import_pop3.o import_imap.o import_gui.o imap.o pop3.o extract.o mydomains.o $objs"
+OBJS="dirs.o base64.o misc.o counters.o cfg.o sig.o decoder.o hash.o parser.o parser_utils.o rules.o smtp.o bdat.o message.o attachment.o digest.o store.o archive.o tai.o import.o import_maildir.o import_mailbox.o import_pop3.o import_imap.o import_gui.o imap.o pop3.o extract.o mydomains.o $objs"
 
 AC_CONFIG_FILES([Makefile src/Makefile etc/Makefile util/Makefile init.d/Makefile unit_tests/Makefile contrib/imap/Makefile])
 AC_OUTPUT
diff --git a/src/Makefile.in b/src/Makefile.in
index 4c5ef87a..fc139378 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -33,7 +33,7 @@ MAKE = `which make`
 
 INSTALL = @INSTALL@
 
-all: libpiler.a piler pilerconf pilerget pileraget pilerimport pilerexport pilerpurge reindex test
+all: libpiler.a piler pilerconf pilerget pileraget pilerimport pilerexport pilerpurge reindex test piler-smtp
 install: install-piler
 
 
@@ -47,6 +47,8 @@ libpiler.a: $(OBJS) $(SQL_OBJS)
 	ln -sf libpiler.so.$(LIBPILER_VERSION) libpiler.so
 	ln -sf libpiler.so.$(LIBPILER_VERSION) libpiler.so.$(PILER_VERSION)
 
+piler-smtp: piler-smtp.c libpiler.a
+	$(CC) $(CFLAGS) $(INCDIR) $(DEFS) -o $@ $< cfg.o misc.o tai.o smtp.o dirs.o sig.o bdat.o $(LIBS) $(LIBDIR)
 
 pilerget: pilerget.c libpiler.a
 	$(CC) $(CFLAGS) $(INCDIR) $(DEFS) -o $@ $< -lpiler $(LIBS) $(LIBDIR)
@@ -83,6 +85,7 @@ install-piler:
 	(cd $(DESTDIR)$(libdir) && ln -sf libpiler.so.$(LIBPILER_VERSION) libpiler.so.$(PILER_VERSION))
 
 	$(INSTALL) -m 0755 piler $(DESTDIR)$(sbindir)
+	$(INSTALL) -m 0755 piler-smtp $(DESTDIR)$(sbindir)
 	$(INSTALL) -m 0755 pilerconf $(DESTDIR)$(sbindir)
 	$(INSTALL) -m 6755 -o $(RUNNING_USER) -g $(RUNNING_GROUP) pilerget $(DESTDIR)$(bindir)
 	$(INSTALL) -m 6755 -o $(RUNNING_USER) -g $(RUNNING_GROUP) pileraget $(DESTDIR)$(bindir)
@@ -93,7 +96,7 @@ install-piler:
 	$(INSTALL) -m 6755 -o $(RUNNING_USER) -g $(RUNNING_GROUP) pilertest $(DESTDIR)$(bindir)
 
 clean:
-	rm -f *.o *.a libpiler.so* piler pilerconf pilerget pileraget pilerimport pilerexport pilerpurge pilertest reindex
+	rm -f *.o *.a libpiler.so* piler pilerconf pilerget pileraget pilerimport pilerexport pilerpurge pilertest reindex piler-smtp
 
 distclean: clean
 	rm -f Makefile
diff --git a/src/bdat.c b/src/bdat.c
new file mode 100644
index 00000000..14e90294
--- /dev/null
+++ b/src/bdat.c
@@ -0,0 +1,136 @@
+/*
+ * bdat.c, SJ
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <signal.h>
+#include <syslog.h>
+#include <time.h>
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <piler.h>
+#include <smtp.h>
+
+
+void reset_bdat_counters(struct smtp_session *session){
+   session->bdat_rounds = 0;
+   session->bdat_last_round = 0;
+   session->bdat_bytes_to_read = 0;
+   session->bad = 0;
+}
+
+
+void get_bdat_size_to_read(struct smtp_session *session, char *buf){
+   char *p;
+
+   session->bdat_rounds++;
+   session->bdat_bytes_to_read = 0;
+
+   session->protocol_state = SMTP_STATE_BDAT;
+
+   // determine if this is the last BDAT command
+
+   p = strcasestr(buf, " LAST");
+   if(p){
+      session->bdat_last_round = 1;
+      syslog(LOG_INFO, "%s: BDAT LAST", session->ttmpfile);
+      *p = '\0';
+   }
+
+   // determine the size to be read
+
+   p = strchr(buf, ' ');
+   if(p){
+      session->bdat_bytes_to_read = atoi(p);
+      if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_INFO, "%s: BDAT len=%d", session->ttmpfile, session->bdat_bytes_to_read);
+   }
+
+   if(!p || session->bdat_bytes_to_read <= 0){
+      session->bdat_bytes_to_read = 0;
+      syslog(LOG_INFO, "%s: malformed BDAT command", session->ttmpfile);
+   }
+}
+
+
+void process_bdat(struct smtp_session *session, char *readbuf, int readlen){
+   int i;
+   char buf[SMALLBUFSIZE];
+
+   if(readlen <= 0) return;
+
+   //printf("readbuf in process_bdat (%d): *%s*\n", readlen, readbuf);
+
+   if(session->bdat_rounds == 1){
+      session->fd = open(session->ttmpfile, O_CREAT|O_RDWR, S_IRUSR|S_IWUSR|S_IRGRP);
+      if(session->fd == -1){
+         syslog(LOG_PRIORITY, "%s: %s", ERR_OPEN_TMP_FILE, session->ttmpfile);
+      }
+   }
+
+   session->bdat_bytes_to_read -= readlen;
+
+   if(session->fd != -1){
+      write(session->fd, readbuf, readlen);
+      session->tot_len += readlen;
+
+      if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_INFO, "%s: wrote %d bytes, %d bytes to go", session->ttmpfile, readlen, session->bdat_bytes_to_read);
+   }
+
+   
+   if(session->bdat_bytes_to_read < 0){
+      // malformed data from client: we got more data then had been told in BDAT argument
+      syslog(LOG_PRIORITY, "ERROR: invalid BDAT data. Expected %d, got %d bytes", session->bdat_bytes_to_read + readlen, readlen);
+      session->bad = 1;
+
+      close(session->fd);
+      unlink(session->ttmpfile);
+   }
+
+   if(session->bdat_bytes_to_read == 0){
+
+      if(session->bdat_last_round == 1){
+         if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_INFO, "%s: read all bdat data in %d rounds", session->ttmpfile, session->bdat_rounds);
+
+         // send back the smtp answers
+         for(i=0; i<session->bdat_rounds; i++){
+            if(session->fd == -1){
+               send_smtp_response(session, SMTP_RESP_421_ERR_WRITE_FAILED);
+            }
+            else {
+               if(i == 0){
+                  fsync(session->fd);
+                  close(session->fd);
+
+                  move_email(session);
+
+                  snprintf(buf, sizeof(buf)-1, "250 OK <%s>\r\n", session->ttmpfile);
+                  send_smtp_response(session, buf);
+                  syslog(LOG_PRIORITY, "received: %s, from=%s, size=%d", session->ttmpfile, session->mailfrom, session->tot_len);
+               }
+               else send_smtp_response(session, SMTP_RESP_250_BDAT);
+            }
+         }
+
+         // technically we are not in the PERIOD state, but it's good enough
+         // to quit the BDAT processing state
+         session->protocol_state = SMTP_STATE_PERIOD;
+
+         session->fd = -1;
+      }
+
+      else {
+         // this is not the last BDAT round, let's go back
+         // after the rcpt state, and wait for the next
+         // BDAT command
+         session->protocol_state = SMTP_STATE_RCPT_TO;
+      }
+   }
+}
diff --git a/src/cfg.c b/src/cfg.c
index 1ce2ddd0..11f70a88 100644
--- a/src/cfg.c
+++ b/src/cfg.c
@@ -101,6 +101,7 @@ struct _parse_rule config_parse_rules[] =
    { "process_rcpt_to_addresses", "integer", (void*) int_parser, offsetof(struct __config, process_rcpt_to_addresses), "0", sizeof(int)},
    { "queuedir", "string", (void*) string_parser, offsetof(struct __config, queuedir), QUEUE_DIR, MAXVAL-1},
    { "server_id", "integer", (void*) int_parser, offsetof(struct __config, server_id), "0", sizeof(int)},
+   { "smtp_timeout", "integer", (void*) int_parser, offsetof(struct __config, smtp_timeout), "60", sizeof(int)},
    { "spam_header_line", "string", (void*) string_parser, offsetof(struct __config, spam_header_line), "", MAXVAL-1},
    { "syslog_recipients", "integer", (void*) int_parser, offsetof(struct __config, syslog_recipients), "0", sizeof(int)},
    { "tls_enable", "integer", (void*) int_parser, offsetof(struct __config, tls_enable), "0", sizeof(int)},
diff --git a/src/cfg.h b/src/cfg.h
index 8689d9ca..bd1a3e66 100644
--- a/src/cfg.h
+++ b/src/cfg.h
@@ -48,6 +48,7 @@ struct __config {
    int verbosity;
    char locale[MAXVAL];
 
+   int smtp_timeout;
    int helper_timeout;
    int extract_attachments;
 
diff --git a/src/config.h b/src/config.h
index 4ac5f4c2..0458a194 100644
--- a/src/config.h
+++ b/src/config.h
@@ -11,9 +11,9 @@
 
 #define PROGNAME "piler"
 
-#define VERSION "1.2.0"
+#define VERSION "1.3.0-master"
 
-#define BUILD 952
+#define BUILD 975
 
 #define HOSTID "mailarchiver"
 
diff --git a/src/defs.h b/src/defs.h
index 3f56adf1..4107f046 100644
--- a/src/defs.h
+++ b/src/defs.h
@@ -22,6 +22,7 @@
 
 #include <openssl/sha.h>
 #include <openssl/ssl.h>
+#include <netinet/in.h>
 #include "tai.h"
 #include "config.h"
 
@@ -64,9 +65,6 @@
 #define RULE_NO_MATCH -100
 
 
-typedef void signal_func (int);
-
-
 struct child {
    pid_t pid;
    int serial;
@@ -386,6 +384,26 @@ struct session_ctx {
    struct counters *counters;
 };
 
+struct smtp_session {
+   char ttmpfile[SMALLBUFSIZE];
+   char mailfrom[SMALLBUFSIZE];
+   char buf[SMALLBUFSIZE];
+   char remote_host[INET6_ADDRSTRLEN];
+   time_t lasttime;
+   int protocol_state;
+   int fd;
+   int bad;
+   int buflen;
+   int tot_len;
+   int bdat_rounds;
+   int bdat_last_round;
+   int bdat_bytes_to_read;
+   int socket;
+   struct __config *cfg;
+   SSL_CTX *ctx;
+   SSL *ssl;
+   int use_ssl;
+   int starttls;
+};
 
 #endif /* _DEFS_H */
-
diff --git a/src/dirs.c b/src/dirs.c
index e4067884..b83e8d96 100644
--- a/src/dirs.c
+++ b/src/dirs.c
@@ -18,6 +18,7 @@ void createdir(char *path, uid_t uid, gid_t gid, mode_t mode);
 
 void check_and_create_directories(struct __config *cfg, uid_t uid, gid_t gid){
    char *p, s[SMALLBUFSIZE];
+   int i;
 
    p = strrchr(cfg->workdir, '/');
    if(p){
@@ -45,6 +46,11 @@ void check_and_create_directories(struct __config *cfg, uid_t uid, gid_t gid){
       *p = '/';
    }
 
+   for(i=0; i<cfg->number_of_worker_processes; i++){
+      snprintf(s, sizeof(s)-1, "%s/%d", cfg->workdir, i);
+      createdir(s, uid, gid, 0700);
+   }
+
 }
 
 
diff --git a/src/misc.c b/src/misc.c
index c006a8cc..542e3e23 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -107,6 +107,21 @@ int searchStringInBuffer(char *s, int len1, char *what, int len2){
 }
 
 
+int search_char_backward(char *buf, int buflen, char c){
+   int n, m;
+
+   m = buflen - 1 - 5;
+   if(m < 0) m = 0;
+
+   for(n=m; n<buflen; n++){
+      if(*(buf + n) == c){
+         return n;
+      }
+   }
+   return -1;
+}
+
+
 /*
  * count a character in buffer
  */
@@ -627,6 +642,17 @@ int can_i_write_current_directory(){
 }
 
 
+void move_email(struct smtp_session *session){
+   char buf[SMALLBUFSIZE];
+
+   snprintf(buf, sizeof(buf)-1, "%d/%s", session->ttmpfile[RND_STR_LEN-1] % session->cfg->number_of_worker_processes, session->ttmpfile);
+
+   if(rename(session->ttmpfile, buf)){
+      syslog(LOG_PRIORITY, "ERROR: couldn't rename %s to %s", session->ttmpfile, buf);
+   }
+}
+
+
 #ifndef _GNU_SOURCE
 char *strcasestr(const char *s, const char *find){
    char c, sc;
@@ -647,4 +673,3 @@ char *strcasestr(const char *s, const char *find){
    return((char*)s);
 }
 #endif
-
diff --git a/src/misc.h b/src/misc.h
index 89a40500..0412e2d4 100644
--- a/src/misc.h
+++ b/src/misc.h
@@ -20,6 +20,7 @@ void get_extractor_list();
 void __fatal(char *s);
 long tvdiff(struct timeval a, struct timeval b);
 int searchStringInBuffer(char *s, int len1, char *what, int len2);
+int search_char_backward(char *buf, int buflen, char c);
 int countCharacterInBuffer(char *p, char c);
 void replaceCharacterInBuffer(char *p, char from, char to);
 char *split(char *str, int ch, char *buf, int buflen, int *result);
@@ -46,6 +47,8 @@ void *get_in_addr(struct sockaddr *sa);
 
 int can_i_write_current_directory();
 
+void move_email(struct smtp_session *session);
+
 #ifndef _GNU_SOURCE
    char *strcasestr(const char *s, const char *find);
 #endif
diff --git a/src/piler-smtp.c b/src/piler-smtp.c
new file mode 100644
index 00000000..e6b341cf
--- /dev/null
+++ b/src/piler-smtp.c
@@ -0,0 +1,472 @@
+/*
+ * piler-smtp.c
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <pwd.h>
+#include <sys/ioctl.h>
+#include <signal.h>
+#include <poll.h>
+#include <netinet/in.h>
+#include <locale.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <time.h>
+#include <syslog.h>
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <piler.h>
+
+#define POLL_SIZE 256
+
+extern char *optarg;
+extern int optind;
+ 
+struct pollfd poll_set[POLL_SIZE];
+int timeout = 20; // checking for timeout this often [sec]
+int numfds = 0;
+int listenerfd = -1;
+
+char *configfile = CONFIG_FILE;
+struct __config cfg;
+struct passwd *pwd;
+struct smtp_session *session, *sessions[POLL_SIZE];
+
+
+void handle_data(struct smtp_session *session, char *readbuf, int readlen){
+   char *p, puf[MAXBUFSIZE];
+   int result;
+
+   // process BDAT stuff
+
+   if(session->protocol_state == SMTP_STATE_BDAT){
+      if(session->bad == 1){
+         // something bad happened in the BDAT processing
+         return;
+      }
+
+      process_bdat(session, readbuf, readlen);
+   }
+
+   // process DATA
+
+   else if(session->protocol_state == SMTP_STATE_DATA){
+      process_data(session, readbuf, readlen);
+   }
+
+   // process other SMTP commands
+
+   else {
+      //printf("len=%d, buf=*%s*\n\n\n", readlen, readbuf);
+
+      if(session->buflen > 0){
+         snprintf(puf, sizeof(puf)-1, "%s%s", session->buf, readbuf);
+         snprintf(readbuf, BIGBUFSIZE-1, "%s", puf);
+
+         session->buflen = 0;
+         memset(session->buf, 0, SMALLBUFSIZE);
+      }
+
+      p = readbuf;
+
+      do {
+         memset(puf, 0, sizeof(puf));
+         p = split(p, '\n', puf, sizeof(puf)-1, &result);
+
+         if(puf[0] == '\0') continue;
+
+         if(result == 1){
+            process_smtp_command(session, puf);
+
+            // if chunking is enabled and we have data after BDAT <len>
+            // then process the rest
+
+            if(session->cfg->enable_chunking == 1 && p && session->protocol_state == SMTP_STATE_BDAT){
+               process_bdat(session, p, strlen(p));
+               break;
+            }
+         }
+         else {
+            snprintf(session->buf, SMALLBUFSIZE-1, "%s", puf);
+            session->buflen = strlen(puf);
+         }
+      } while(p);
+
+   }
+
+}
+
+
+void init_smtp_session(struct smtp_session *session, int fd_index, int sd){
+   session->socket = sd;
+   session->buflen = 0;
+   session->protocol_state = SMTP_STATE_INIT;
+
+   session->cfg = &cfg;
+
+   session->use_ssl = 0;  // use SSL/TLS
+   session->starttls = 0; // SSL/TLS communication is active (1) or not (0)
+   session->ctx = NULL;
+   session->ssl = NULL;
+
+   memset(session->buf, 0, SMALLBUFSIZE);
+   memset(session->remote_host, 0, INET6_ADDRSTRLEN);
+
+   reset_bdat_counters(session);
+
+   time(&(session->lasttime));
+}
+
+
+void free_smtp_session(struct smtp_session *session){
+
+   if(session){
+      //printf("freeing session\n");
+
+      if(session->use_ssl == 1){
+         //printf("shutdown ssl\n");
+         SSL_shutdown(session->ssl);
+         SSL_free(session->ssl);
+      }
+
+      if(session->ctx) SSL_CTX_free(session->ctx);
+
+      free(session);
+   }
+}
+
+
+
+void p_clean_exit(){
+   int i;
+
+   if(listenerfd != -1) close(listenerfd);
+
+   for(i=1; i<numfds; i++){
+      close(poll_set[i].fd);
+      free_smtp_session(sessions[i]);
+   }
+
+   syslog(LOG_PRIORITY, "%s has been terminated", PROGNAME);
+
+   //unlink(cfg.pidfile);
+
+   ERR_free_strings();
+
+   exit(1);
+}
+
+
+void fatal(char *s){
+   syslog(LOG_PRIORITY, "%s", s);
+   p_clean_exit();
+}
+
+
+void tear_down_client(int n){
+   int i;
+
+   close(poll_set[n].fd);
+   poll_set[n].events = 0;
+
+   syslog(LOG_PRIORITY, "disconnected from %s", sessions[n]->remote_host);
+
+   // new code
+   free_smtp_session(sessions[n]);
+   sessions[n] = NULL;
+
+   for(i=n; i<numfds; i++){
+      poll_set[i] = poll_set[i+1];
+      sessions[i] = sessions[i+1];
+   }
+
+   numfds--;
+}
+
+
+void check_for_client_timeout(){
+   time_t now;
+   int i;
+
+   if(numfds > 1){
+      time(&now);
+
+      for(i=1; i<numfds; i++){
+         if(now - sessions[i]->lasttime >= cfg.smtp_timeout){
+            syslog(LOG_PRIORITY, "client %s timeout", sessions[i]->remote_host);
+            tear_down_client(i);
+         }
+      }
+   }
+
+   alarm(timeout);
+}
+
+
+#ifdef HAVE_LIBWRAP
+int is_blocked_by_tcp_wrappers(int sd){
+   struct request_info req;
+
+   request_init(&req, RQ_DAEMON, PROGNAME, RQ_FILE, sd, 0);
+
+   fromhost(&req);
+
+   if(!hosts_access(&req)){
+      send(sd, SMTP_RESP_550_ERR_YOU_ARE_BANNED_BY_LOCAL_POLICY, strlen(SMTP_RESP_550_ERR_YOU_ARE_BANNED_BY_LOCAL_POLICY), 0);
+      syslog(LOG_PRIORITY, "denied connection from %s by tcp_wrappers", eval_client(&req));
+      return 1;
+   }
+
+   return 0;
+}
+#endif
+
+
+int create_listener_socket(char *listen_addr, int listen_port){
+   int rc, sd, yes=1;
+   char port_string[8];
+   struct addrinfo hints, *res;
+
+   memset(&hints, 0, sizeof(hints));
+   hints.ai_family = AF_UNSPEC;
+   hints.ai_socktype = SOCK_STREAM;
+
+   snprintf(port_string, sizeof(port_string)-1, "%d", listen_port);
+
+   if((rc = getaddrinfo(listen_addr, port_string, &hints, &res)) != 0){
+      syslog(LOG_PRIORITY, "getaddrinfo for '%s': %s", listen_addr, gai_strerror(rc));
+      return -1;
+   }
+
+   if((sd = socket(res->ai_family, res->ai_socktype, res->ai_protocol)) == -1){
+      syslog(LOG_PRIORITY, "socket() error");
+      return -1;
+   }
+
+   if(setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1){
+      syslog(LOG_PRIORITY, "setsockopt() error");
+      close(sd);
+      return -1;
+   }
+
+   if(ioctl(sd, FIONBIO, (char *)&yes) == -1){
+      syslog(LOG_PRIORITY, "ioctl() failed");
+      close(sd);
+      return -1;
+   }
+
+   if(bind(sd, res->ai_addr, res->ai_addrlen) == -1){
+      syslog(LOG_PRIORITY, "cannot bind to port: %s:%d", listen_addr, listen_port);
+      close(sd);
+      return -1;
+   }
+
+   freeaddrinfo(res);
+
+   if(listen(sd, cfg.backlog) == -1){
+      syslog(LOG_PRIORITY, "listen() error");
+      close(sd);
+      return -1;
+   }
+
+   return sd;
+}
+
+
+void start_new_session(int socket, struct sockaddr_storage client_address, int fd_index){
+   char smtp_banner[SMALLBUFSIZE], remote_host[INET6_ADDRSTRLEN];
+
+   // Uh-oh! We have enough connections to serve already
+   if(numfds >= POLL_SIZE){
+      inet_ntop(client_address.ss_family, get_in_addr((struct sockaddr*)&client_address), remote_host, sizeof(remote_host));
+      syslog(LOG_PRIORITY, "too many connections (%d), cannot accept %s", numfds, remote_host);
+      send(socket, SMTP_RESP_421_ERR_ALL_PORTS_ARE_BUSY, strlen(SMTP_RESP_421_ERR_ALL_PORTS_ARE_BUSY), 0);
+      close(socket);
+      return;
+   }
+
+#ifdef HAVE_LIBWRAP
+   if(is_blocked_by_tcp_wrappers(socket) == 1){
+      close(socket);
+      return;
+   }
+#endif
+
+   sessions[numfds] = malloc(sizeof(struct smtp_session));
+
+   if(sessions[numfds] == NULL){
+      syslog(LOG_PRIORITY, "malloc error()");
+      send(socket, SMTP_RESP_421_ERR_TMP, strlen(SMTP_RESP_421_ERR_TMP), 0);
+      close(socket);
+      return;
+   }
+
+
+   init_smtp_session(sessions[numfds], fd_index, socket);
+
+   snprintf(smtp_banner, sizeof(smtp_banner)-1, SMTP_RESP_220_BANNER, cfg.hostid);
+   send(socket, smtp_banner, strlen(smtp_banner), 0);
+
+   inet_ntop(client_address.ss_family, get_in_addr((struct sockaddr*)&client_address), sessions[numfds]->remote_host, INET6_ADDRSTRLEN);
+
+   syslog(LOG_PRIORITY, "connected from %s", sessions[numfds]->remote_host);
+
+   poll_set[numfds].fd = socket;
+   poll_set[numfds].events = POLLIN|POLLHUP;
+
+   numfds++;
+}
+
+
+void initialise_configuration(){
+   cfg = read_config(configfile);
+
+   if(strlen(cfg.username) > 1){
+      pwd = getpwnam(cfg.username);
+      if(!pwd) fatal(ERR_NON_EXISTENT_USER);
+   }
+
+   if(getuid() == 0 && pwd){
+      check_and_create_directories(&cfg, pwd->pw_uid, pwd->pw_gid);
+   }
+
+   if(chdir(cfg.workdir)){
+      syslog(LOG_PRIORITY, "workdir: *%s*", cfg.workdir);
+      fatal(ERR_CHDIR);
+   }
+
+   setlocale(LC_MESSAGES, cfg.locale);
+   setlocale(LC_CTYPE, cfg.locale);
+
+   syslog(LOG_PRIORITY, "reloaded config: %s", configfile);
+}
+
+
+int main(int argc, char **argv){
+   int listenerfd, client_sockfd;
+   int i, daemonise=0;
+   int client_len = sizeof(struct sockaddr_storage);
+   int readlen;
+   int bytes_to_read;
+   struct sockaddr_storage client_address;
+   char readbuf[BIGBUFSIZE];
+
+   while((i = getopt(argc, argv, "c:dvVh")) > 0){
+      switch(i){
+
+        case 'c' :
+                   configfile = optarg;
+                   break;
+
+        case 'd' :
+                   daemonise = 1;
+                   break;
+
+        case 'v' :
+        case 'V' :
+                   printf("%s build %d\n", VERSION, get_build());
+                   return 0;
+
+        case 'h' :
+        default  : 
+                   __fatal("usage: ...");
+      }
+   }
+
+   (void) openlog("piler-poll", LOG_PID, LOG_MAIL);
+
+   memset(sessions, '\0', sizeof(sessions));
+   memset(poll_set, '\0', sizeof(poll_set));
+
+   initialise_configuration();
+
+   listenerfd = create_listener_socket(cfg.listen_addr, cfg.listen_port);
+   if(listenerfd == -1){
+      syslog(LOG_PRIORITY, "create_listener_socket() error");
+      exit(1);
+   }
+
+   if(drop_privileges(pwd)) fatal(ERR_SETUID);
+
+   set_signal_handler(SIGTERM, p_clean_exit);
+   set_signal_handler(SIGALRM, check_for_client_timeout);
+   set_signal_handler(SIGHUP, initialise_configuration);
+
+   alarm(timeout);
+
+   poll_set[0].fd = listenerfd;
+   poll_set[0].events = POLLIN;
+   numfds = 1;
+
+   SSL_library_init();
+   SSL_load_error_strings();
+
+   srand(getpid());
+
+#if HAVE_DAEMON == 1
+   if(daemonise == 1 && daemon(1, 0) == -1) fatal(ERR_DAEMON);
+#endif
+
+   for(;;){
+      int fd_index;
+ 
+      poll(poll_set, numfds, -1);
+
+      for(fd_index = 0; fd_index < numfds; fd_index++){
+         if(poll_set[fd_index].revents & POLLIN){
+
+            // process new connection
+
+            if(poll_set[fd_index].fd == listenerfd){
+               client_sockfd = accept(listenerfd, (struct sockaddr *)&client_address, (socklen_t *)&client_len);
+               start_new_session(client_sockfd, client_address, fd_index);
+            }
+
+            // handle data from an existing connection
+
+            else {
+               ioctl(poll_set[fd_index].fd, FIONREAD, &bytes_to_read);
+
+               if(cfg.verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "got %d bytes to read", bytes_to_read);
+
+               if(bytes_to_read == 0){
+                  tear_down_client(fd_index);
+               }
+               else {
+                  session = sessions[fd_index];
+
+                  time(&(session->lasttime));
+
+                  // readbuf must be large enough to hold 'bytes_to_read' data
+                  // I think there shouldn't be more than MTU size data to be
+                  // read from the socket at a time
+                  memset(readbuf, 0, sizeof(readbuf));
+
+                  if(session->use_ssl == 1)
+                     readlen = SSL_read(session->ssl, (char*)&readbuf[0], sizeof(readbuf)-1);
+                  else
+                     readlen = recv(poll_set[fd_index].fd, &readbuf[0], sizeof(readbuf)-1, 0);
+
+                  if(readlen < 1) break;
+
+                  readbuf[readlen] = '\0'; // we need either this or memset(readbuf, ...) above
+
+                  handle_data(session, &readbuf[0], readlen);
+
+                  if(session->protocol_state == SMTP_STATE_BDAT && session->bad == 1) tear_down_client(fd_index);
+               }
+            }
+         }
+      }
+   }
+
+   return 0;
+}
diff --git a/src/piler.c b/src/piler.c
index e59d84f1..029197b2 100644
--- a/src/piler.c
+++ b/src/piler.c
@@ -102,16 +102,24 @@ static void child_sighup_handler(int sig){
 
 
 static void child_main(struct child *ptr){
-   char s[INET6_ADDRSTRLEN];
-   struct sockaddr_storage client_addr;
-   socklen_t addr_size;
-   struct session_ctx sctx;
+   struct import import;
+   struct session_data sdata;
+   int tot_msgs = 0;
+   char dir[TINYBUFSIZE];
+
+   /* open directory, then process its files, then sleep 2 sec, and repeat */
+
+   import.total_messages = import.total_size = import.processed_messages = import.batch_processing_limit = 0;
+   import.remove_after_import = 1;
+   import.extra_recipient = import.move_folder = NULL;
+
+   data.import = &import;
 
    ptr->messages = 0;
-   sctx.data = &data;
-   sctx.cfg = &cfg;
 
-   if(cfg.verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "child (pid: %d, serial: %d) started main()", getpid(), ptr->serial);
+   snprintf(dir, sizeof(dir)-1, "%d", ptr->serial);
+
+   if(cfg.verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "child (pid: %d, serial: %d) started main() working on '%s'", getpid(), ptr->serial, dir);
 
    while(1){
       if(received_sighup == 1){
@@ -119,35 +127,30 @@ static void child_main(struct child *ptr){
          break;
       }
 
-      ptr->status = READY;
-
-      addr_size = sizeof(client_addr);
-      sctx.new_sd = accept(sd, (struct sockaddr *)&client_addr, &addr_size);
-
-      if(sctx.new_sd == -1) continue;
-
-      ptr->status = BUSY;
-
-      inet_ntop(client_addr.ss_family, get_in_addr((struct sockaddr *)&client_addr), s, sizeof(s)-1);
-
-      syslog(LOG_PRIORITY, "connection from %s", s);
-
-      data.child_serial = ptr->serial;
-
       sig_block(SIGHUP);
-      ptr->messages += handle_smtp_session(&sctx);
-      sig_unblock(SIGHUP);
 
-      close(sctx.new_sd);
+      if(open_database(&sdata, &cfg) == OK){
+         import_from_maildir(dir, &sdata, &data, &tot_msgs, &cfg);
+         ptr->messages += tot_msgs;
+         close_database(&sdata);
 
-      if(cfg.max_requests_per_child > 0 && ptr->messages >= cfg.max_requests_per_child){
-         if(cfg.verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "child (pid: %d, serial: %d) served enough: %d", getpid(), ptr->messages, ptr->serial);
-         break;
+         sleep(2);
+      }
+      else {
+         syslog(LOG_PRIORITY, "ERROR: cannot open database");
+         sleep(10);
       }
 
-   }
+      sig_unblock(SIGHUP);
 
-   ptr->status = UNDEF;
+      // TODO: do we want to quit after processing a certain number of messages?
+
+      //if(cfg.max_requests_per_child > 0 && ptr->messages >= cfg.max_requests_per_child){
+      //   if(cfg.verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "child (pid: %d, serial: %d) served enough: %d", getpid(), ptr->messages, ptr->serial);
+      //   break;
+      //}
+
+   }
 
 #ifdef HAVE_MEMCACHED
    memcached_shutdown(&(data.memc));
@@ -409,7 +412,8 @@ int main(int argc, char **argv){
 
    snprintf(port_string, sizeof(port_string)-1, "%d", cfg.listen_port);
 
-   if((rc = getaddrinfo(cfg.listen_addr, port_string, &hints, &res)) != 0){
+   //if((rc = getaddrinfo(cfg.listen_addr, port_string, &hints, &res)) != 0){
+   if((rc = getaddrinfo("127.0.0.1", "5678", &hints, &res)) != 0){
       fprintf(stderr, "getaddrinfo for '%s': %s\n", cfg.listen_addr, gai_strerror(rc));
       return 1;
    }
@@ -466,4 +470,3 @@ int main(int argc, char **argv){
 
    return 0;
 }
-
diff --git a/src/piler.h b/src/piler.h
index 920952a5..d20fbf54 100644
--- a/src/piler.h
+++ b/src/piler.h
@@ -19,6 +19,7 @@
 #include <rules.h>
 #include <sql.h>
 #include <import.h>
+#include <smtp.h>
 #include <config.h>
 #include <unistd.h>
 
@@ -29,6 +30,8 @@
 int read_key(struct __config *cfg);
 void insert_offset(struct session_data *sdata, int server_id);
 
+void tear_down_client(int n);
+
 int do_av_check(struct session_data *sdata, char *virusinfo, struct __data *data, struct __config *cfg);
 
 int make_digests(struct session_data *sdata, struct __config *cfg);
@@ -69,7 +72,6 @@ int is_email_address_on_my_domains(char *email, struct __data *data);
 int is_blocked_by_tcp_wrappers(int sd);
 void send_response_to_data(struct session_ctx *sctx, char *rcptto);
 void process_written_file(struct session_ctx *sctx);
-void process_data(struct session_ctx *sctx);
 
 #endif /* _PILER_H */
 
diff --git a/src/sig.h b/src/sig.h
index 86e1e3a8..103fb0a2 100644
--- a/src/sig.h
+++ b/src/sig.h
@@ -5,6 +5,8 @@
 #ifndef _SIG_H
  #define _SIG_H
 
+typedef void signal_func (int);
+
 void sig_block(int sig);
 void sig_unblock(int sig);
 void sig_catch(int sig, void (*f)());
diff --git a/src/smtp.c b/src/smtp.c
index 8490d5fb..91164adb 100644
--- a/src/smtp.c
+++ b/src/smtp.c
@@ -1,285 +1,319 @@
-/*
- * smtp.c, SJ
- */
-
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <strings.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
 #include <fcntl.h>
-#include <unistd.h>
-#include <signal.h>
 #include <syslog.h>
-#include <time.h>
+#include <unistd.h>
 #include <openssl/ssl.h>
 #include <openssl/err.h>
 #include <piler.h>
-#include <smtp.h>
+#include "smtp.h"
 
 
-void process_command_ehlo_lhlo(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen){
-   char tmpbuf[MAXBUFSIZE];
+void process_smtp_command(struct smtp_session *session, char *buf){
+   char response[SMALLBUFSIZE];
+
+   if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "processing command: *%s*", buf);
+
+   if(strncasecmp(buf, SMTP_CMD_HELO, strlen(SMTP_CMD_HELO)) == 0){
+      process_command_helo(session, response, sizeof(response));
+      return;
+   }
+
+   if(strncasecmp(buf, SMTP_CMD_EHLO, strlen(SMTP_CMD_EHLO)) == 0 ||
+         strncasecmp(buf, LMTP_CMD_LHLO, strlen(LMTP_CMD_LHLO)) == 0){
+      process_command_ehlo_lhlo(session, response, sizeof(response));
+      return;
+   }
+
+   if(strncasecmp(buf, SMTP_CMD_MAIL_FROM, strlen(SMTP_CMD_MAIL_FROM)) == 0){
+      process_command_mail_from(session, buf);
+      return;
+   }
+
+   if(strncasecmp(buf, SMTP_CMD_RCPT_TO, strlen(SMTP_CMD_RCPT_TO)) == 0){
+      process_command_rcpt_to(session, buf);
+      return;
+   }
+
+   if(strncasecmp(buf, SMTP_CMD_DATA, strlen(SMTP_CMD_DATA)) == 0){
+      process_command_data(session);
+      return;
+   }
+
+   if(session->cfg->enable_chunking == 1 && strncasecmp(buf, SMTP_CMD_BDAT, strlen(SMTP_CMD_BDAT)) == 0){
+      get_bdat_size_to_read(session, buf);
+      return;
+   }
+
+   if(strncasecmp(buf, SMTP_CMD_QUIT, strlen(SMTP_CMD_QUIT)) == 0){
+      process_command_quit(session, response, sizeof(response));
+      return;
+   }
+
+   if(strncasecmp(buf, SMTP_CMD_RESET, strlen(SMTP_CMD_RESET)) == 0){
+      process_command_reset(session);
+      return;
+   }
+
+   if(session->cfg->tls_enable == 1 && strncasecmp(buf, SMTP_CMD_STARTTLS, strlen(SMTP_CMD_STARTTLS)) == 0 && session->use_ssl == 0){
+      process_command_starttls(session);
+      return;
+   }
+
+   send_smtp_response(session, SMTP_RESP_502_ERR);
+}
+
+
+void process_data(struct smtp_session *session, char *readbuf, int readlen){
+   char puf[SMALLBUFSIZE+BIGBUFSIZE];
+   int n, pos, len;
+
+   memset(puf, 0, sizeof(puf));
+
+   if(session->buflen > 0){
+      memcpy(&puf[0], session->buf, session->buflen);
+      memcpy(&puf[session->buflen], readbuf, readlen);
+      len = session->buflen + readlen;
+   }
+   else {
+      memcpy(&puf[0], readbuf, readlen);
+      len = readlen;
+   }
+
+   pos = searchStringInBuffer(&puf[0], len, SMTP_CMD_PERIOD, 5);
+
+   if(pos > 0){
+      //write(session->fd, puf, pos+2);
+      //session->tot_len += pos+2;
+      write(session->fd, puf, pos);
+      session->tot_len += pos;
+      process_command_period(session);
+   }
+   else {
+      n = search_char_backward(&puf[0], len, '\r');
+
+      if(n == -1 || len - n > 4){
+         write(session->fd, puf, len);
+         session->tot_len += len;
+      }
+      else {
+         write(session->fd, puf, n);
+         session->tot_len += n;
+
+         snprintf(session->buf, SMALLBUFSIZE-1, "%s", &puf[n]);
+         session->buflen = len - n;
+      }
+   }
+}
+
+
+void send_smtp_response(struct smtp_session *session, char *buf){
+   int rc;
+   char ssl_error[SMALLBUFSIZE];
+
+   write1(session->socket, buf, strlen(buf), session->use_ssl, session->ssl);
+
+   if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "sent: %s", buf);
+
+   if(session->starttls == 1 && session->use_ssl == 0){
+
+      if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "waiting for ssl handshake");
+
+      rc = SSL_accept(session->ssl);
+
+      if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "SSL_accept() finished");
+
+      if(rc == 1){
+         session->use_ssl = 1;
+      }
+      else {
+         ERR_error_string_n(ERR_get_error(), ssl_error, SMALLBUFSIZE);
+         syslog(LOG_PRIORITY, "%s: SSL_accept() failed, rc=%d, errorcode: %d, error text: %s\n", session->ttmpfile, rc, SSL_get_error(session->ssl, rc), ssl_error);
+      }
+   }
+}
+
+
+void process_command_helo(struct smtp_session *session, char *buf, int buflen){
+   if(session->protocol_state == SMTP_STATE_INIT) session->protocol_state = SMTP_STATE_HELO;
+
+   snprintf(buf, buflen-1, "220 %s ESMTP\r\n", session->cfg->hostid);
+   send_smtp_response(session, buf);
+}
+
+
+void process_command_ehlo_lhlo(struct smtp_session *session, char *buf, int buflen){
    char extensions[SMALLBUFSIZE];
 
    memset(extensions, 0, sizeof(extensions));
 
-   if(*protocol_state == SMTP_STATE_INIT) *protocol_state = SMTP_STATE_HELO;
+   if(session->protocol_state == SMTP_STATE_INIT) session->protocol_state = SMTP_STATE_HELO;
 
-   if(sctx->sdata->tls == 0) snprintf(extensions, sizeof(extensions)-1, "%s", sctx->data->starttls);
-   if(sctx->cfg->enable_chunking == 1) strncat(extensions, SMTP_EXTENSION_CHUNKING, sizeof(extensions)-strlen(extensions)-2);
+   // if tls is not started, but it's enabled in the config
+   if(session->use_ssl == 0 && session->cfg->tls_enable == 1) snprintf(extensions, sizeof(extensions)-1, "%s", SMTP_EXTENSION_STARTTLS);
+   if(session->cfg->enable_chunking == 1) strncat(extensions, SMTP_EXTENSION_CHUNKING, sizeof(extensions)-strlen(extensions)-2);
 
-   snprintf(tmpbuf, sizeof(tmpbuf)-1, SMTP_RESP_250_EXTENSIONS, sctx->cfg->hostid, extensions);
+   snprintf(buf, buflen-1, SMTP_RESP_250_EXTENSIONS, session->cfg->hostid, extensions);
 
-   strncat(resp, tmpbuf, resplen-strlen(resp));
+   send_smtp_response(session, buf);
 }
 
 
-void process_command_starttls(struct session_ctx *sctx, int *protocol_state, int *starttls, char *resp, int resplen){
+int init_ssl(struct smtp_session *session){
+   session->ctx = SSL_CTX_new(TLSv1_server_method());
 
-   if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "%s: starttls request from client", sctx->sdata->ttmpfile);
+   if(session->ctx == NULL){
+      syslog(LOG_PRIORITY, "%s: SSL ctx is null!", session->ttmpfile);
+      return 0;
+   }
 
-   if(sctx->data->ctx){
-      sctx->data->ssl = SSL_new(sctx->data->ctx);
-      if(sctx->data->ssl){
+   if(SSL_CTX_set_cipher_list(session->ctx, session->cfg->cipher_list) == 0){
+      syslog(LOG_PRIORITY, "failed to set cipher list: '%s'", session->cfg->cipher_list);
+      return 0;
+   }
 
-         SSL_set_options(sctx->data->ssl, SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3);
+   if(SSL_CTX_use_PrivateKey_file(session->ctx, session->cfg->pemfile, SSL_FILETYPE_PEM) != 1){
+      syslog(LOG_PRIORITY, "cannot load private key from %s", session->cfg->pemfile);
+      return 0;
+   }
 
-         if(SSL_set_fd(sctx->data->ssl, sctx->new_sd) == 1){
-            strncat(resp, SMTP_RESP_220_READY_TO_START_TLS, resplen);
-            *starttls = 1;
-            *protocol_state = SMTP_STATE_INIT;
+   if(SSL_CTX_use_certificate_file(session->ctx, session->cfg->pemfile, SSL_FILETYPE_PEM) != 1){
+      syslog(LOG_PRIORITY, "cannot load certificate from %s", session->cfg->pemfile);
+      return 0;
+   }
+
+   return 1;
+}
+
+
+void process_command_starttls(struct smtp_session *session){
+   if(session->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "starttls request from client");
+
+   if(init_ssl(session) == 1){
+
+      session->ssl = SSL_new(session->ctx);
+      if(session->ssl){
+
+         SSL_set_options(session->ssl, SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3);
+
+         if(SSL_set_fd(session->ssl, session->socket) == 1){
+            session->starttls = 1;
+            send_smtp_response(session, SMTP_RESP_220_READY_TO_START_TLS);
+            session->protocol_state = SMTP_STATE_INIT;
+            session->use_ssl = 1;
             return;
-         } syslog(LOG_PRIORITY, "%s: SSL_set_fd() failed", sctx->sdata->ttmpfile);
-      } syslog(LOG_PRIORITY, "%s: SSL_new() failed", sctx->sdata->ttmpfile);
-   } syslog(LOG_PRIORITY, "%s: SSL ctx is null!", sctx->sdata->ttmpfile);
+         } syslog(LOG_PRIORITY, "%s: SSL_set_fd() failed", session->ttmpfile);
+      } syslog(LOG_PRIORITY, "%s: SSL_new() failed", session->ttmpfile);
+   } syslog(LOG_PRIORITY, "%s: SSL ctx is null!", session->ttmpfile);
 
-   strncat(resp, SMTP_RESP_454_ERR_TLS_TEMP_ERROR, resplen);
+   send_smtp_response(session, SMTP_RESP_454_ERR_TLS_TEMP_ERROR);
 }
 
 
-void process_command_mail_from(struct session_ctx *sctx, int *protocol_state, char *buf, char *resp, int resplen){
+void process_command_mail_from(struct smtp_session *session, char *buf){
+   memset(session->mailfrom, 0, SMALLBUFSIZE);
 
-   if(*protocol_state != SMTP_STATE_HELO && *protocol_state != SMTP_STATE_PERIOD && *protocol_state != SMTP_STATE_BDAT){
-      strncat(resp, SMTP_RESP_503_ERR, resplen);
+   if(session->protocol_state != SMTP_STATE_HELO && session->protocol_state != SMTP_STATE_PERIOD && session->protocol_state != SMTP_STATE_BDAT){
+      send(session->socket, SMTP_RESP_503_ERR, strlen(SMTP_RESP_503_ERR), 0);
    }
    else {
-      if(*protocol_state == SMTP_STATE_PERIOD || *protocol_state == SMTP_STATE_BDAT){
-         if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "%s: initiated new transaction", sctx->sdata->ttmpfile);
+      create_id(&(session->ttmpfile[0]), 15);
+      session->protocol_state = SMTP_STATE_MAIL_FROM;
 
-         unlink(sctx->sdata->ttmpfile);
-         unlink(sctx->sdata->tmpframe);
+      extractEmail(buf, session->mailfrom);
 
-         init_session_data(sctx->sdata, sctx->cfg);
-      }
+      reset_bdat_counters(session);
+      session->tot_len = 0;
 
-      *protocol_state = SMTP_STATE_MAIL_FROM;
-
-      snprintf(sctx->sdata->mailfrom, SMALLBUFSIZE-1, "%s\r\n", buf);
-
-      memset(sctx->sdata->fromemail, 0, SMALLBUFSIZE);
-      extractEmail(sctx->sdata->mailfrom, sctx->sdata->fromemail);
-
-      strncat(resp, SMTP_RESP_250_OK, strlen(SMTP_RESP_250_OK));
-
-   }
-
-}
-
-
-void process_command_rcpt_to(struct session_ctx *sctx, int *protocol_state, char *buf, char *resp, int resplen){
-
-   if(*protocol_state == SMTP_STATE_MAIL_FROM || *protocol_state == SMTP_STATE_RCPT_TO){
-
-      if(strlen(buf) > SMALLBUFSIZE/2){
-         strncat(resp, SMTP_RESP_550_ERR_TOO_LONG_RCPT_TO, resplen);
-         return;
-      }
-
-      if(sctx->sdata->num_of_rcpt_to < MAX_RCPT_TO-1){
-         extractEmail(buf, sctx->sdata->rcptto[sctx->sdata->num_of_rcpt_to]);
-      }
-
-      *protocol_state = SMTP_STATE_RCPT_TO;
-
-      if(sctx->sdata->num_of_rcpt_to < MAX_RCPT_TO-1) sctx->sdata->num_of_rcpt_to++;
-
-      strncat(resp, SMTP_RESP_250_OK, resplen);
-   }
-   else {
-      strncat(resp, SMTP_RESP_503_ERR, resplen);
+      send_smtp_response(session, SMTP_RESP_250_OK);
    }
 }
 
 
-void process_command_data(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen){
+void process_command_rcpt_to(struct smtp_session *session, char *buf){
 
-   if(*protocol_state != SMTP_STATE_RCPT_TO){
-      strncat(resp, SMTP_RESP_503_ERR, resplen);
+   if(session->protocol_state == SMTP_STATE_MAIL_FROM || session->protocol_state == SMTP_STATE_RCPT_TO){
+
+      // For now, we are not interested in the envelope recipients
+
+      session->protocol_state = SMTP_STATE_RCPT_TO;
+      send_smtp_response(session, SMTP_RESP_250_OK);
    }
    else {
-      sctx->sdata->fd = open(sctx->sdata->filename, O_CREAT|O_RDWR, S_IRUSR|S_IWUSR|S_IRGRP);
-      if(sctx->sdata->fd == -1){
-         syslog(LOG_PRIORITY, "%s: %s", ERR_OPEN_TMP_FILE, sctx->sdata->ttmpfile);
-         strncat(resp, SMTP_RESP_451_ERR, resplen);
+      send_smtp_response(session, SMTP_RESP_503_ERR);
+   }
+}
+
+
+void process_command_data(struct smtp_session *session){
+   session->tot_len = 0;
+
+   if(session->protocol_state != SMTP_STATE_RCPT_TO){
+      send_smtp_response(session, SMTP_RESP_503_ERR);
+   }
+   else {
+      session->fd = open(session->ttmpfile, O_CREAT|O_RDWR, S_IRUSR|S_IWUSR|S_IRGRP);
+      if(session->fd == -1){
+         syslog(LOG_PRIORITY, "%s: %s", ERR_OPEN_TMP_FILE, session->ttmpfile);
+         send_smtp_response(session, SMTP_RESP_451_ERR);
       }
       else {
-         *protocol_state = SMTP_STATE_DATA;
-         strncat(resp, SMTP_RESP_354_DATA_OK, resplen-1);
+         session->protocol_state = SMTP_STATE_DATA;
+         send_smtp_response(session, SMTP_RESP_354_DATA_OK);
       }
    }
 
 }
 
+void process_command_period(struct smtp_session *session){
+   char buf[SMALLBUFSIZE];
 
-void process_command_bdat(struct session_ctx *sctx, int *protocol_state, char *buf, char *resp, int resplen){
-   int n, expected_bdat_len;
-   char puf[MAXBUFSIZE];
+   session->protocol_state = SMTP_STATE_PERIOD;
 
-   if(*protocol_state != SMTP_STATE_RCPT_TO){
-      strncat(resp, SMTP_RESP_503_ERR, resplen);
-      return;
-   }
+   // TODO: add some error handling
 
-   sctx->bdat_rounds = 0;
-   sctx->bdat_last_round = 0;
+   fsync(session->fd);
+   close(session->fd);
 
-   while(sctx->bdat_last_round != 1){
-      sctx->bdat_rounds++;
-      expected_bdat_len = 0;
+   session->fd = -1;
 
-      if(sctx->bdat_rounds == 1){
-         expected_bdat_len = extract_bdat_command(sctx, buf);
+   syslog(LOG_PRIORITY, "received: %s, from=%s, size=%d", session->ttmpfile, session->mailfrom, session->tot_len);
 
-         sctx->sdata->fd = open(sctx->sdata->filename, O_CREAT|O_RDWR, S_IRUSR|S_IWUSR|S_IRGRP);
-         if(sctx->sdata->fd == -1){
-            syslog(LOG_PRIORITY, "%s: %s", ERR_OPEN_TMP_FILE, sctx->sdata->ttmpfile);
-            strncat(resp, SMTP_RESP_451_ERR, resplen);
-            return;
-         }
-         else {
-            *protocol_state = SMTP_STATE_BDAT;
-         }
-      }
-      else if(sctx->bdat_last_round != 1){
-         if((n = recvtimeoutssl(sctx->new_sd, &puf[0], sizeof(puf), TIMEOUT, sctx->sdata->tls, sctx->data->ssl)) > 0){
-            expected_bdat_len = extract_bdat_command(sctx, puf);
-            if(expected_bdat_len <= 0 && sctx->bdat_rounds > 0) sctx->bdat_rounds--;
-         }
-      }
+   move_email(session);
 
-      if(expected_bdat_len > 0) sctx->sdata->tot_len += read_bdat_data(sctx, expected_bdat_len);
-   }
+   snprintf(buf, sizeof(buf)-1, "250 OK <%s>\r\n", session->ttmpfile);
 
-   fsync(sctx->sdata->fd);
-   close(sctx->sdata->fd);
+   session->buflen = 0;
+   memset(session->buf, 0, SMALLBUFSIZE);
+
+   send_smtp_response(session, buf);
 }
 
 
-int extract_bdat_command(struct session_ctx *sctx, char *buf){
-   int expected_bdat_len=0;
-   char *p;
+void process_command_quit(struct smtp_session *session, char *buf, int buflen){
+   session->protocol_state = SMTP_STATE_FINISHED;
 
-   // determine if this is the last BDAT command
+   snprintf(buf, buflen-1, SMTP_RESP_221_GOODBYE, session->cfg->hostid);
 
-   p = strcasestr(buf, " LAST");
-   if(p){
-      sctx->bdat_last_round = 1;
-      syslog(LOG_INFO, "%s: BDAT LAST", sctx->sdata->ttmpfile);
-      *p = '\0';
-   }
-
-   // determine the size to be read
-
-   p = strchr(buf, ' ');
-   if(p){
-      expected_bdat_len = atoi(p);
-      if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_INFO, "%s: BDAT len=%d", sctx->sdata->ttmpfile, expected_bdat_len);
-   }
-
-   if(!p || expected_bdat_len <= 0){
-      syslog(LOG_INFO, "%s: malformed BDAT command", sctx->sdata->ttmpfile);
-      return -1;
-   }
-
-   return expected_bdat_len;
+   send_smtp_response(session, buf);
 }
 
 
-int read_bdat_data(struct session_ctx *sctx, int expected_bdat_len){
-   int n, read_bdat_len=0, written_bdat_len=0;
-   char puf[MAXBUFSIZE];
+void process_command_reset(struct smtp_session *session){
+   send_smtp_response(session, SMTP_RESP_250_OK);
 
-   while(read_bdat_len < expected_bdat_len){
-      if((n = recvtimeoutssl(sctx->new_sd, &puf[0], sizeof(puf), TIMEOUT, sctx->sdata->tls, sctx->data->ssl)) > 0){
-         read_bdat_len += n;
-         written_bdat_len += write(sctx->sdata->fd, puf, n);
-      }
-   }
+   session->tot_len = 0;
+   session->fd = -1;
+   session->protocol_state = SMTP_STATE_HELO;
 
-   if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_INFO, "%s: wrote %d bytes of BDAT data", sctx->sdata->ttmpfile, written_bdat_len);
+   reset_bdat_counters(session);
 
-   return written_bdat_len;
+   create_id(&(session->ttmpfile[0]), 15);
 }
 
-
-void process_command_quit(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen){
-   char tmpbuf[MAXBUFSIZE];
-
-   *protocol_state = SMTP_STATE_FINISHED;
-
-   snprintf(tmpbuf, sizeof(tmpbuf)-1, SMTP_RESP_221_GOODBYE, sctx->cfg->hostid);
-   strncat(resp, tmpbuf, resplen);
-
-   unlink(sctx->sdata->ttmpfile);
-   unlink(sctx->sdata->tmpframe);
-
-   if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "%s: removed", sctx->sdata->ttmpfile);
-}
-
-
-void process_command_reset(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen){
-
-   strncat(resp, SMTP_RESP_250_OK, resplen);
-
-   if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "%s: removed", sctx->sdata->ttmpfile);
-
-   unlink(sctx->sdata->ttmpfile);
-   unlink(sctx->sdata->tmpframe);
-
-   init_session_data(sctx->sdata, sctx->cfg);
-
-   *protocol_state = SMTP_STATE_HELO;
-}
-
-
-void send_buffered_response(struct session_ctx *sctx, int starttls, char *resp){
-   int rc;
-   char ssl_error[SMALLBUFSIZE];
-
-   write1(sctx->new_sd, resp, strlen(resp), sctx->sdata->tls, sctx->data->ssl);
-
-   if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "%s: sent: %s", sctx->sdata->ttmpfile, resp);
-   memset(resp, 0, MAXBUFSIZE);
-
-   if(starttls == 1 && sctx->sdata->tls == 0){
-
-      if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "%s: waiting for ssl handshake", sctx->sdata->ttmpfile);
-
-      rc = SSL_accept(sctx->data->ssl);
-
-      if(sctx->cfg->verbosity >= _LOG_DEBUG) syslog(LOG_PRIORITY, "%s: SSL_accept() finished", sctx->sdata->ttmpfile);
-
-      if(rc == 1){
-         sctx->sdata->tls = 1;
-      }
-      else {
-         ERR_error_string_n(ERR_get_error(), ssl_error, SMALLBUFSIZE);
-         syslog(LOG_PRIORITY, "%s: SSL_accept() failed, rc=%d, errorcode: %d, error text: %s\n", sctx->sdata->ttmpfile, rc, SSL_get_error(sctx->data->ssl, rc), ssl_error);
-      }
-   }
-}
-
-
diff --git a/src/smtp.h b/src/smtp.h
index 177cdee3..46fc2cd4 100644
--- a/src/smtp.h
+++ b/src/smtp.h
@@ -5,18 +5,24 @@
 #ifndef _SMTP_H
  #define _SMTP_H
 
-void process_command_ehlo_lhlo(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen);
-void process_command_starttls(struct session_ctx *sctx, int *protocol_state, int *starttls, char *resp, int resplen);
-void process_command_mail_from(struct session_ctx *sctx, int *protocol_state, char *buf, char *resp, int resplen);
-void process_command_rcpt_to(struct session_ctx *sctx, int *protocol_state, char *buf, char *resp, int resplen);
-void process_command_data(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen);
-void process_command_bdat(struct session_ctx *sctx, int *protocol_state, char *buf, char *resp, int resplen);
-void process_command_quit(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen);
-void process_command_reset(struct session_ctx *sctx, int *protocol_state, char *resp, int resplen);
+#include <piler.h>
 
-int read_bdat_data(struct session_ctx *sctx, int expected_bdat_len);
-int extract_bdat_command(struct session_ctx *sctx, char *buf);
+void process_smtp_command(struct smtp_session *session, char *buf);
+void process_data(struct smtp_session *session, char *readbuf, int readlen);
 
-void send_buffered_response(struct session_ctx *sctx, int starttls, char *resp);
+void send_smtp_response(struct smtp_session *session, char *buf);
+void process_command_helo(struct smtp_session *session, char *buf, int buflen);
+void process_command_ehlo_lhlo(struct smtp_session *session, char *buf, int buflen);
+void process_command_quit(struct smtp_session *session, char *buf, int buflen);
+void process_command_reset(struct smtp_session *session);
+void process_command_mail_from(struct smtp_session *session, char *buf);
+void process_command_rcpt_to(struct smtp_session *session, char *buf);
+void process_command_data(struct smtp_session *session);
+void process_command_period(struct smtp_session *session);
+void process_command_starttls(struct smtp_session *session);
 
-#endif /* _SMTP_H */
+void reset_bdat_counters(struct smtp_session *session);
+void get_bdat_size_to_read(struct smtp_session *session, char *buf);
+void process_bdat(struct smtp_session *session, char *readbuf, int readlen);
+
+#endif
diff --git a/src/smtpcodes.h b/src/smtpcodes.h
index 141df0e4..0aa0d500 100644
--- a/src/smtpcodes.h
+++ b/src/smtpcodes.h
@@ -48,6 +48,7 @@
 #define SMTP_RESP_421_ERR "421 %s Error: timed out\r\n"
 #define SMTP_RESP_421_ERR_TMP "421 %s service not available\r\n"
 #define SMTP_RESP_421_ERR_WRITE_FAILED "421 writing queue file failed\r\n"
+#define SMTP_RESP_421_ERR_ALL_PORTS_ARE_BUSY "421 All server ports are busy\r\n"
 #define SMTP_RESP_450_ERR_CMD_NOT_IMPLEMENTED "450 command not implemented\r\n"
 #define SMTP_RESP_451_ERR "451 Error in processing, try again later\r\n"
 #define SMTP_RESP_454_ERR_TLS_TEMP_ERROR "454 TLS not available currently\r\n"
@@ -56,7 +57,6 @@
 #define SMTP_RESP_503_ERR "503 Bad command sequence\r\n"
 #define SMTP_RESP_530_ERR_MUST_ISSUE_STARTTLS_FIRST "530 MUST issue STARTTLS command first\r\n"
 #define SMTP_RESP_550_ERR "550 Access denied.\r\n"
-#define SMTP_RESP_550_ERR_PREF "550 Access denied."
 #define SMTP_RESP_550_INVALID_RECIPIENT "550 Unknown recipient\r\n"
 #define SMTP_RESP_550_ERR_TOO_LONG_RCPT_TO "550 too long recipient\r\n"
 #define SMTP_RESP_550_ERR_YOU_ARE_BANNED_BY_LOCAL_POLICY "550 You are banned by local policy\r\n"