msmtp/msmtpq

   1 #!/usr/bin/env bash
   2
   3 ##--------------------------------------------------------------
   4 ##
   5 ##  msmtpq : queue funtions to both use & manage the msmtp queue,
   6 ##             as it was defined by Martin Lambers
   7 ##  Copyright (C) 2008, 2009, 2010, 2011 Chris Gianniotis
   8 ##
   9 ##  This program is free software: you can redistribute it and/or modify
  10 ##  it under the terms of the GNU General Public License as published by
  11 ##  the Free Software Foundation, either version 3 of the License, or, at
  12 ##  your option, any later version.
  13 ##
  14 ##--------------------------------------------------------------
  15
  16 ## msmtpq is meant to be used by an email client - in 'sendmail' mode
  17 ##   for this purpose, it is invoked directly as 'msmtpq'
  18 ## it is also meant to be used to maintain the msmtp queue
  19 ##   evoked by the wrapper script 'msmtp-queue'
  20 ##   (which calls this script as msmtpq --q-mgmt)
  21
  22 ## there is a queue log file, distinct from the msmtp log,
  23 ##   for all events & operations on the msmtp queue
  24 ##   that is defined below
  25
  26 ## (mutt users, using msmtpq in 'sendmail' mode,
  27 ##  should make at least the following two settings in their .muttrc
  28 ##    set sendmail = /path/to/msmtpq
  29 ##    set sendmail_wait = -1
  30 ##
  31 ##  please see the msmtp man page and docs for further mutt settings
  32 ##    and optimisations
  33 ## )
  34
  35 ## msmtpq now uses the following environment variables :
  36 ##   EMAIL_CONN_NOTEST   if set will suppress any testing for a connection
  37 ##   EMAIL_CONN_TEST     if unset or =p will use a ping test (debian.org) for a connection
  38 ##                       if =P will use a fast ping test (8.8.8.8) for a connection
  39 ##                       if =n will use netcat (nc) to test for a connection
  40 ##                       if =s will use bash sockets to test for a connection
  41 ##   EMAIL_QUEUE_QUIET   if set will cause suppression of messages and 'chatter'
  42
  43 ## two essential patches by Philipp Hartwig
  44 ## 19 Oct 2011 & 27 Oct 2011
  45
  46 ##--------------------------------------------------------------
  47 ## the msmtp queue contains unique filenames of the following form :
  48 ##   two files for each mail in the queue
  49 ##
  50 ## creates new unique filenames of the form :
  51 ##   MLF: ccyy-mm-dd-hh.mm.ss[-x].mail   -- mail file
  52 ##   MSF: ccyy-mm-dd-hh.mm.ss[-x].msmtp  -- msmtp command line file
  53 ## where x is a consecutive number only appended for uniqueness
  54 ##   if more than one mail per second is sent
  55 ##--------------------------------------------------------------
  56
  57
  58 dsp() { local L ; for L ; do [ -n "$L" ] && echo "  $L" || echo ; done ; }
  59 err() { dsp '' "$@" '' ; exit 1 ; }
  60
  61
  62 ## ======================================================================================
  63 ##      !!!          please define or confirm the following three vars           !!!
  64 ##      !!!           before using the msmtpq or msmtp-queue scripts             !!!
  65 ## ======================================================================================
  66 ##
  67 ## only if necessary (in unusual circumstances - e.g. embedded systems),
  68 ##   enter the location of the msmtp executable  (no quotes !!)
  69 ##   e.g. ( MSMTP=/path/to/msmtp )
  70 MSMTP=msmtp
  71 #[ -x "$MSMTP" ] || \
  72 #  log -e 1 "msmtpq : can't find the msmtp executable [ $MSMTP ]"   # if not found - complain ; quit
  73 ##
  74 ## set the queue var to the location of the msmtp queue directory
  75 ##   if the queue dir doesn't yet exist, better to create it (0700)
  76 ##     before using this routine
  77 ##       e.g. ( mkdir msmtp.queue      )
  78 ##            ( chmod 0700 msmtp.queue )
  79 ##
  80 ## the queue dir - modify this to reflect where you'd like it to be  (no quotes !!)
  81 Q=~/.msmtp/queue
  82 [ -d "$Q" ] || \
  83   err '' "msmtpq : can't find msmtp queue directory [ $Q ]" ''     # if not present - complain ; quit
  84 ##
  85 ## set the queue log file var to the location of the msmtp queue log file
  86 ##   where it is or where you'd like it to be
  87 ##     ( note that the LOG setting could be the same as the )
  88 ##     ( 'logfile' setting in .msmtprc - but there may be   )
  89 ##     ( some advantage in keeping the two logs separate    )
  90 ##   if you don't want the log at all unset (comment out) this var
  91 ##     LOG=~/log/msmtp.queue.log  -->  #LOG=~/log/msmtp.queue.log
  92 ##     (doing so would be inadvisable under most conditions, however)
  93 ##
  94 ## the queue log file - modify (or comment out) to taste  (but no quotes !!)
  95 LOG=~/.msmtp/queue.log
  96 ## ======================================================================================
  97
  98 umask 077                            # set secure permissions on created directories and files
  99
 100 declare -i CNT                       # a count of mail(s) currently in the queue
 101 declare -a Q_LST                     # queue list array ; used selecting a mail (to send or remove)
 102
 103 ## do ; test this !
 104 #for sig in INT TERM EXIT; do
 105 #  trap "rm -f \"\$TMPFILE\"; [[ $sig == EXIT ]] || kill -$sig $$" $sig
 106 #done
 107 trap on_exit INT TERM EXIT           # run 'on_exit' on exit
 108 on_exit() {
 109   [ -n "$LKD" ] && lock_queue -u 2>/dev/null   # unlock the queue on exit if the lock was set here
 110 }
 111
 112 #
 113 ## ----------------------------------- common functions
 114 #
 115
 116 ## make an entry to the queue log file, possibly an error
 117 ## (log queue changes only ; not interactive chatter)
 118 ## usage : log [ -e errcode ] msg [ msg ... ]
 119 ##  opts : -e <exit code>  an error ; log msg & terminate w/prejudice
 120 ## display msg to user, as well
 121 log() {
 122   local ARG RC PFX="$('date' +'%Y %d %b %H:%M:%S')"
 123                                      # time stamp prefix - "2008 13 Mar 03:59:45 "
 124   if [ "$1" = '-e' ] ; then          # there's an error exit code
 125     RC="$2"                          # take it
 126     shift 2                          # shift opt & its arg off
 127   fi
 128
 129   [ -z "$EMAIL_QUEUE_QUIET" ] && dsp "$@"  # display msg to user, as well as logging it
 130
 131   if [ -n "$LOG" ] ; then            # log is defined and in use
 132     for ARG ; do                     # each msg line out
 133       [ -n "$ARG" ] && \
 134         echo "$PFX : $ARG" >> "$LOG" # line has content ; send it to log
 135     done
 136   fi
 137
 138   if [ -n "$RC" ] ; then             # an error ; leave w/error return
 139     [ -n "$LKD" ] && lock_queue -u   # unlock here (if locked)
 140     [ -n "$LOG" ] && \
 141       echo "    exit code = $RC" >> "$LOG" # logging ok ; send exit code to log
 142     exit $RC                         # exit w/return code
 143   fi
 144 }
 145
 146 ## write/remove queue lockfile for a queue op
 147 lock_queue() {        # <-- '-u' to remove lockfile
 148   local LOK="${Q}/.lock"             # lock file name
 149   local -i MAX=240 SEC=0             # max seconds to gain a lock ; seconds waiting
 150
 151   if [ -z "$1" ] ; then              # lock queue
 152     ## Philipp Hartwig patch #2
 153     'mkdir' "$LOK" 2>/dev/null && LKD='t'
 154     while [ -z "$LKD" ] && (( SEC < MAX )) ; do      # lock file present
 155           sleep 1                                        # wait a second
 156             (( ++SEC ))                                    # accumulate seconds
 157       'mkdir' "$LOK" 2>/dev/null && LKD='t'          # make lockdir ; lock queue ; set flag
 158     done                                             # try again while locked for MAX secs
 159     [ -z "$LKD" ] && \
 160             err '' "cannot use queue $Q : waited $MAX seconds for"\
 161                    "  lockdir [ $LOK ] to vanish ; giving up"\
 162                    'if you are certain that no other instance of this script'\
 163                    "  is running, then 'rmdir' the lock dir manually" '' # lock file still there, give up
 164
 165   elif [ "$1" = '-u' ] ; then        # unlock queue
 166     'rmdir' "$LOK"                   # remove the lock
 167     unset LKD                        # unset flag
 168   fi
 169 }
 170
 171 ## test whether system is connected
 172 ## returns t/f (0/1)
 173 connect_test() {
 174   if [ -z "$EMAIL_CONN_TEST" ] || \
 175      [ "$EMAIL_CONN_TEST" = 'p' ] ; then                       # use ping test (default)
 176     # verify net connection - ping ip address of debian.org
 177     # would ping -qnc2 -w4 be better ?
 178     # would ping -qnc1 -w10 or -w20 be better ?
 179     ping -qnc1 -w4 debian.org >/dev/null 2>&1 || return 1
 180   elif [ "$EMAIL_CONN_TEST" = 'P' ] ; then                     # use quicker ping test
 181     # I personally think that including a DNS lookup
 182     # is a better connection test but some
 183     # have found the above test too slow
 184     ping -qnc1 -w4 8.8.8.8 >/dev/null 2>&1 || return 1
 185   elif [ "$EMAIL_CONN_TEST" = 'n' ] ; then                     # use netcat (nc) test
 186     # must, of course, have netcat (nc) installed
 187     which nc >/dev/null 2>&1 || \
 188       log -e 1 "msmtpq : can't find netcat executable [ nc ]"  # if not found - complain ; quit
 189     'nc' -vz www.debian.org 80 || return 1
 190   elif [ "$EMAIL_CONN_TEST" = 's' ] ; then                     # use sh sockets test
 191     # note that this does not work on debian systems
 192     # where bash opened sockets are suppressed for security reasons
 193     # this should be ok for single user systems (including embedded systems)
 194     # test whether this is supported on your system before using
 195     exec 3<>/dev/udp/debian.org/80 || return 1                 # open socket on site ; use dns
 196     exec 3<&- ; exec 3>&-                                      # close socket
 197   fi
 198   return 0
 199 }
 200
 201 #
 202 ## ----------------------------------- functions for queue management
 203 ## ----------------------------------- queue maintenance mode - (msmtp-queue)
 204 #
 205
 206 ## show queue maintenance functions
 207 usage() {        # <-- error msg
 208   dsp ''\
 209       'usage : msmtp-queue functions' ''\
 210       '        msmtp-queue < op >'\
 211       '        ops : -r   run (flush) mail queue - all mail in queue'\
 212       '              -R   send selected individual mail(s) in queue'\
 213       '              -d   display (list) queue contents   (<-- default)'\
 214       '              -p   purge individual mail(s) from queue'\
 215       '              -a   purge all mail in queue'\
 216       '              -h   this helpful blurt' ''\
 217       '        ( one op only ; any others ignored )' ''
 218   [ -z "$1" ] && exit 0 || { dsp "$@" '' ; exit 1 ; }
 219 }
 220
 221 ## get user [y/n] acknowledgement
 222 ok() {
 223   local R YN='Y/n'                   # default to yes
 224
 225   [ "$1" = '-n' ] && \
 226     { YN='y/N' ; shift ; }           # default to no ; change prompt ; shift off spec
 227
 228   dsp "$@"
 229   while true ; do
 230     echo -n "  ok [${YN}] ..: "
 231     read R
 232     case $R in
 233       y|Y) return 0 ;;
 234       n|N) return 1 ;;
 235       '')  [ "$YN" = 'Y/n' ] && return 0 || return 1 ;;
 236       *)   echo 'yYnN<cr> only please' ;;
 237     esac
 238   done
 239 }
 240
 241 ## send a queued mail out via msmtp
 242 send_queued_mail() {   # <-- mail id
 243   local FQP="${Q}/${1}"              # fully qualified path name
 244   local -i RC=0                      # for msmtp exit code
 245
 246   if [ -f "${FQP}.msmtp" ] ; then    # corresponding .msmtp file found
 247     [ -z "$EMAIL_CONN_NOTEST" ] && { # connection test
 248       connect_test || \
 249         log "mail [ $2 ] [ $1 ] from queue ; couldn't be sent - host not connected"
 250     }
 251
 252     if $MSMTP $(< "${FQP}.msmtp") < "${FQP}.mail" ; then       # this mail goes out the door
 253       log "mail [ $2 ] [ $1 ] from queue ; send was successful ; purged from queue"  # good news to user
 254       'rm' -f ${FQP}.*                                         # nuke both queue mail files
 255       ALT='t'                        # set queue changed flag
 256     else                             # send was unsuccessful
 257       RC=$?                          # take msmtp exit code
 258       log "mail [ $2 ] [ $1 ] from queue ; send failed ; msmtp rc = $RC" # bad news ...
 259     fi
 260     return $RC                       # func returns exit code
 261   else                               # corresponding MSF file not found
 262     log "preparing to send .mail file [ $1 ] [ ${FQP}.mail ] but"\
 263         "  corresponding .msmtp file [ ${FQP}.msmtp ] was not found in queue"\
 264         '  skipping this mail ; this is worth looking into'    # give user the bad news
 265   fi                                                           # (but allow continuation)
 266 }
 267
 268 ## run (flush) queue
 269 run_queue() {    # <- 'sm' mode      # run queue
 270   local M LST="$('ls' $Q/*.mail 2>/dev/null)"            # list of mails in queue
 271   local -i NDX=0
 272
 273   if [ -n "$LST" ] ; then            # something in queue
 274     for M in $LST ; do               # process all mails
 275       ((NDX++))
 276       send_queued_mail "$(basename $M .mail)" "$NDX"     # send mail - pass {id} only
 277     done
 278   else                               # queue is empty
 279     [ -z "$1" ] && \
 280       dsp '' 'mail queue is empty (nothing to send)' ''
 281   fi                                 # inform user (if not running in sendmail mode)
 282 }
 283
 284 ## display queue contents
 285 display_queue() {      # <-- { 'purge' | 'send' } (op label) ; { 'rec' } (record array of mail ids)
 286   local M ID LST="$('ls' ${Q}/*.mail 2>/dev/null)"       # list of mail ids in queue
 287
 288   CNT=0
 289   if [ -n "$LST" ] ; then            # list has contents (any mails in queue)
 290     for M in $LST ; do               # cycle through each
 291       ID="$(basename $M .mail)"      # take mail id from filename
 292       ((CNT++))
 293       dsp '' "mail  num=[ $CNT ]  id=[ $ID ]"                  # show mail id ## patch in
 294       'egrep' -s --colour -h '(^From:|^To:|^Subject:)' "$M"    # show mail info
 295       [ -n "$2" ] && Q_LST[$CNT]="$ID" # bang mail id into array (note 1-based array indexing)
 296     done
 297     echo
 298   else                               # no mails ; no contents
 299     [ -z "$1" ] && \
 300       dsp '' 'no mail in queue' '' || \
 301       dsp '' "mail queue is empty (nothing to $1)" ''    # inform user
 302     exit 0
 303   fi
 304 }
 305
 306 ## delete all mail in queue, after confirmation
 307 purge_queue() {
 308   display_queue 'purge'              # show queue contents
 309   if ok -n 'remove (purge) all mail from the queue' ; then
 310     lock_queue                       # lock here
 311     'rm' -f "$Q"/*.*
 312     log 'msmtp queue purged (all mail)'
 313     lock_queue -u                    # unlock here
 314   else
 315     dsp '' 'nothing done ; queue is untouched' ''
 316   fi
 317 }
 318
 319 ## select a single mail from queue ; delete it or send it
 320 ## select by mail index (position in queue) or mail id
 321 select_mail() {  # <-- < 'purge' | 'send' >
 322   local OK ID                                        # mail id
 323   local -i I NDX                                     # mail index (position in queue)
 324
 325   while true ; do                                    # purge an individual mail from queue
 326     display_queue "$1" 'rec'                         # show queue contents ; make mail ids array
 327
 328     ## allow selection also by mail index
 329     if [ $CNT -eq 1 ] ; then                         # only one mail in queue ; take its id
 330       NDX=1
 331       ID="${Q_LST[1]}"
 332     else                                             # more than one mail ; select its id
 333       while true ; do                                # get mail id
 334         OK='t'                                       # optimistic to a fault
 335         dsp "enter mail number or id to $1"          # <-- num or file name (only, no suff)
 336         echo -n '    ( <cr> alone to exit ) ..: '
 337         read ID
 338         [ -n "$ID" ] || return                       # entry made - or say good bye
 339
 340         if [ "${ID:4:1}" != '-' ] ; then             # mail id *not* entered ; test index num
 341           for (( I=0 ; I<${#ID} ; I++ )) ; do        # test index number
 342             if [[ "${ID:${I}:1}" < '0' || \
 343                   "${ID:${I}:1}" > '9' ]] ; then
 344               dsp '' "[ $ID ] is neither a valid mail id"\
 345                      'nor a valid mail number' ''
 346               unset OK
 347             fi
 348           done
 349           [ -z "$OK" ] && continue                   # format not ok (not all nums)
 350
 351           NDX=$ID
 352           if [ $NDX -lt 1 ] || [ $NDX -gt $CNT ] ; then  # test number range (1 - $CNT)
 353             dsp '' "[ $NDX ] is out of range as a mail number"\
 354                    "validity is from 1 to $CNT"
 355             continue                                 # try again
 356           fi
 357
 358           ID="${Q_LST[$NDX]}"                        # format & range were ok ; use it
 359           break                                      # valid mail selection
 360         else                                         # mail id entered
 361           for (( NDX=1 ; NDX<=${#Q_LST[*]} ; NDX++ )) ; do # find entered id in queue list
 362             [ "$ID" = "${Q_LST[$NDX]}" ] && break
 363           done
 364           [ $NDX -le ${#Q_LST[*]} ] && \
 365             break || \
 366             dsp '' "mail [ $ID ] not found ; invalid id" # mail selection valid (found) or
 367         fi                                               # fell through (not found) complain
 368       done                                               # and ask again
 369     fi
 370
 371     if ok '' "$1 :"\
 372           "  mail num=[ $NDX ]"\
 373           "        id=[ $ID ]" '' ; then             # confirm mail op
 374       if [ "$1" = 'purge' ] ; then                   # purging
 375         lock_queue                                   # lock here
 376         'rm' -f "$Q"/"$ID".*                         # msmtp - nukes single mail (both files) in queue
 377         log "mail [ $ID ] purged from queue"         # log op
 378         lock_queue -u                                # unlock here
 379         ALT='t'                                      # mark that a queue alteration has taken place
 380       else                                           # sending
 381         lock_queue                                   # lock here
 382         send_queued_mail "$ID" "$NDX"                # send out the mail
 383         lock_queue -u                                # unlock here
 384       fi
 385     else                                             # user opts out
 386       dsp '' 'nothing done to this queued email'     # soothe user
 387       [ $CNT -eq 1 ] && break                        # single mail ; user opted out
 388     fi
 389     dsp '' "--------------------------------------------------"
 390   done
 391
 392   if [ -n "$ALT" ] ; then            # queue was changed
 393     dsp '' 'done' ''
 394   else                               # queue is untouched
 395     dsp '' 'nothing done ; queue is untouched' ''
 396   fi
 397 }
 398
 399 #
 400 ## ----------------------------------- functions for directly sending mail
 401 ## ----------------------------------- 'sendmail' mode - (msmtpq)
 402 #
 403
 404 ## ('sendmail' mode only)
 405 ## make base filename id for queue
 406 make_id() {
 407   local -i INC                       # increment counter for (possible) base fqp name collision
 408
 409   ID="$(date +%Y-%m-%d-%H.%M.%S)"    # make filename id for queue    (global
 410   FQP="${Q}/$ID"                     # make fully qualified pathname  vars)
 411   ## Philipp Hartwig patch #1
 412   if [ -f "${FQP}.mail" -o -f "${FQP}.msmtp" ] ; then    # ensure fqp name is unique
 413     INC=1                            # initial increment
 414           while [ -f "${FQP}-${INC}.mail" -o -f "${FQP}-${INC}.msmtp" ] ; do # fqp name w/incr exists
 415       (( ++INC ))                    # bump increment
 416           done
 417           ID="${ID}-${INC}"                # unique ; set id
 418           FQP="${FQP}-${INC}"              # unique ; set fqp name
 419   fi
 420 }
 421
 422 ## ('sendmail' mode only)
 423 ## enqueue a mail
 424 enqueue_mail() { # <-- all mail args ; mail text via TMP
 425   if echo "$@" > "${FQP}.msmtp" ; then     # write msmtp command line to queue .msmtp file
 426     log "enqueued mail as : [ $ID ] ( $* ) : successful" # (queue .mail file is already there)
 427   else                                     # write failed ; bomb
 428     log -e "$?" "queueing - writing msmtp cmd line { $* }"\
 429                 "           to [ ${ID}.msmtp ] : failed"
 430   fi
 431 }
 432
 433 ## ('sendmail' mode only)
 434 ## send a mail (if possible, otherwise enqueue it)
 435 ## if send is successful, msmtp will also log it (if enabled in ~/.msmtprc)
 436 send_mail() {    # <-- all mail args ; mail text via TMP
 437   [ -z "$EMAIL_CONN_NOTEST" ] && {   # connection test
 438     connect_test || {
 439       log "mail for [ $* ] : couldn't be sent - host not connected"
 440       enqueue_mail "$@"              # enqueue the mail
 441     }
 442   }
 443
 444   if $MSMTP "$@" < "${FQP}.mail" > /dev/null ; then      # send mail using queue .mail fil
 445     log "mail for [ $* ] : send was successful"          # log it
 446     'rm' -f ${FQP}.*                 # remove all queue mail files .mail & .msmtp file
 447     run_queue 'sm'                   # run/flush any other mails in queue
 448   else                               # send failed - the mail stays in the queue
 449     log "mail for [ $* ] : send was unsuccessful ; msmtp exit code was $?"\
 450         "enqueued mail as : [ $ID ] ( $* )"    # (queue .mail file is already there)
 451   fi
 452 }
 453
 454 #
 455 ## -- entry point
 456 #
 457
 458 if [ ! "$1" = '--q-mgmt' ] ; then    # msmtpq - sendmail mode
 459   lock_queue                         # lock here
 460   make_id                            # make base queue filename id for this mail
 461   # write mail body text to queue .mail file
 462   cat > "${FQP}.mail" || \
 463     log -e "$?" "creating mail body file [ ${FQP}.mail ] : failed" # test for error
 464   # write msmtp command line to queue .msmtp file
 465   echo "$@" > "${FQP}.msmtp" || \
 466     log -e "$?" "creating msmtp cmd line file { $* }"\
 467                 "           to [ ${ID}.msmtp ] : failed" # test for error
 468   send_mail "$@"                     # send the mail if possible, queue it if not
 469   lock_queue -u                      # unlock here
 470 else                                 # msmtp-queue - queue management mode
 471   shift                              # trim off first (--q-mgmt) arg
 472   OP=${1:1}                          # trim off first char of OP arg
 473   case "$OP" in                      # sort ops ; run according to spec
 474     r)    lock_queue
 475           run_queue
 476           lock_queue -u       ;;     # run (flush) the queue
 477     R)    select_mail send    ;;     # send individual mail(s) in queue
 478     d|'') display_queue       ;;     # display (list) all mail in queue (default)
 479     p)    select_mail purge   ;;     # purge individual mail(s) from queue
 480     a)    purge_queue         ;;     # purge all mail in queue
 481     h)    usage               ;;     # show help
 482     *)    usage "[ -$OP ] is an unknown msmtp-queue option" ;;
 483   esac
 484 fi
 485
 486 exit 0