in 1 minute check..
MAIL SOCKET MANAGEMENT
count number of mail connections (miscconn[user].sock!=-1 && miscconn[user].type==2)
if less than MAX_MAIL_CONNECTIONS
while ((count_current_mail_connections < MAX_MAIL_CONNECTIONS) && (tries <= 2))
find free mail slot
if there is one
do_mail_connect()
if bad connect, increase tries, continue through while
if good, tries = 0
if not ABORT
if not less than MAIL_CONNECTIONS or over # of tries
ABORT
MAIL CONNECTION MANAGEMENT:
if (do_smtp_mail) {
do directory read of maildir/outgoing/ counting (need_connections) up to
MAX_MISC_CONNECTS;
in main while() loop..
if socket readable
get input
if (stage==0 && input contains banner)
stage=1 ready=1
if (stage==1 && input contains good helo reply)
stage=2 ready=1
if (stage==2 && input contains good sender reply)
stage=3 ready=1
if (stage==3 && input contains good recipient reply)
stage=4 ready=1
if (stage==4 && input contains good DATA reply)
stage=5 ready=1
if (stage==5 && input contains good message reply)
stage=2 ready=1
remove queue file
reset file fd,queuename
continue through readacble sockets
if socket writeable
if (ready) {
if (stage==1) {
write helo
ready=0
}
if (stage==2) {
readdir outgoing/ for first queue file
if no queue file exists, close connection, continue;
else rename/move first queue file to outgoing_active/
fopen queue file
fd=FILEHANDLE
queuename=FILENAME
read first line
write out sender
if write fails
close file
move queuename back to outgoing/
close connection
ready=0;
}
if (stage==3) {
read next line
write out recipient
if write fails
close file
move queuename back to outgoing/
close connection
ready=0;
}
if (stage==4) {
write out "DATA"
if write fails
close file
move queuename back to outgoing/
close connection
ready=0;
}
if (stage==5) {
reading next line from file
write out body line
if write fails
close file
move queuename back to outgoing/
close connection
else loop read/write till end
ready=0;
}
}
MAIL COMPOSITION
FILE *get_mailqueue_file(void) {
time_t tm;
int subtime=0;
static FILE *tfp;
tm=time(0);
sprintf(filename,"%s/%s%ld.%d",OUTGOING_MAILDIR,(long)tm,subtime);
while ((tfp=fopen(filename,"r")) && subtime != 100) {
fclose(tfp);
subtime++;
sprintf(filename,"%ld.%d",(long)tm,subtime);
}
if (subtime==100) {
write_log(ERRORLOG,YESTIME,"Could not open a new queue file in fmail()\n");
return NULL;
}
else {
if (!(tfp=fopen(filename,"w"))) {
write_log(ERRORLOG,YESTIME,"Could not open the new queue file %s in fmail()
\n",filename);
return NULL;
}
else return tfp;
}
return NULL;
}
if (!(wfp=get_mailqueue_file())) {
error
}
fprintf(wfp,"%s\n",SYSTEM_EMAIL);
fprintf(wfp,"%s\n",mail_addr);
/* start body */
fclose(wfp);
SMTP CONVERSATION:
220 stevenjude2.compustrat.com ESMTP Postfix
HELO stevenjude2.compustrat.com
250 stevenjude2.compustrat.com
MAIL FROM: joe@blow.com
250 Ok
RCPT TO: receiver@blow.com
250 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
BAD HELO:
HELO
501 Syntax: HELO hostname
BAD FROM:
MAIL FROM:
500 Error: bad syntax
BAD RCPT:
RCPT TO:
501 Syntax: RCPT TO: <address>
FUNCTIONS:
void check_smtp(void);
int do_smtp_connect(void);
FILE *get_mailqueue_file(void);
int queuetoactive_smtp(int user);
int write_smtp_data(int user, int type);
void requeue_smtp(int user);
void check_misc_connects(void);
int find_queue_slot(char *inpstr);
ERROR/FAILURE/SUCCESS CODES:
211 System status, or system help reply
214 Help message
[Information on how to use the receiver or the meaning of a
particular non-standard command; this reply is useful only
to the human user]
220 <domain> Service ready
221 <domain> Service closing transmission channel
250 Requested mail action okay, completed
251 User not local; will forward to <forward-path>
354 Start mail input; end with <CRLF>.<CRLF>
421 <domain> Service not available,
closing transmission channel
[This may be a reply to any command if the service knows it
must shut down]
450 Requested mail action not taken: mailbox unavailable
[E.g., mailbox busy]
451 Requested action aborted: local error in processing
452 Requested action not taken: insufficient system storage
500 Syntax error, command unrecognized
[This may include errors such as command line too long]
501 Syntax error in parameters or arguments
502 Command not implemented
503 Bad sequence of commands
504 Command parameter not implemented
550 Requested action not taken: mailbox unavailable
[E.g., mailbox not found, no access]
551 User not local; please try <forward-path>
552 Requested mail action aborted: exceeded storage allocation
553 Requested action not taken: mailbox name not allowed
[E.g., mailbox syntax incorrect]
554 Transaction failed
COMMAND-REPLY SEQUENCES:
"P" = preliminary
"I" = intermediate
"S" = success
"F" = failure
"E" = error
CONNECTION ESTABLISHMENT
S: 220
F: 421
HELO
S: 250
E: 500, 501, 504, 421
MAIL
S: 250
F: 552, 451, 452
E: 500, 501, 421
RCPT
S: 250, 251
F: 550, 551, 552, 553, 450, 451, 452
E: 500, 501, 503, 421
DATA
I: 354 -> data -> S: 250
F: 552, 554, 451, 452
F: 451, 554
E: 500, 501, 503, 421
RSET
S: 250
E: 500, 501, 504, 421
SEND
S: 250
F: 552, 451, 452
E: 500, 501, 502, 421
SOML
S: 250
F: 552, 451, 452
E: 500, 501, 502, 421
SAML
S: 250
F: 552, 451, 452
E: 500, 501, 502, 421
VRFY
S: 250, 251
F: 550, 551, 553
E: 500, 501, 502, 504, 421
EXPN
S: 250
F: 550
E: 500, 501, 502, 504, 421
HELP
S: 211, 214
E: 500, 501, 502, 504, 421
NOOP
S: 250
E: 500, 421
QUIT
S: 221
E: 500
TURN
S: 250
F: 502
E: 500, 503
