summaryrefslogtreecommitdiff
path: root/lib/keyringer/functions
blob: 72286ff7eeaca01f4bc7df8668ed3510089444f3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
#!/usr/bin/env bash
#
# Common functions.
#

# Setup main configuration and load preferences
function keyringer_config_load {
  if [ -f "$HOME/.$NAME" ]; then
    echo "Converting legacy configuration scheme..."
    mv "$HOME/.$NAME" "$HOME/.$NAME.tmp"
    mkdir "$HOME/.$NAME"
    mv "$HOME/.$NAME.tmp" "$CONFIG"
  fi

  if [ ! -e "$CONFIG" ]; then
    echo "Creating $CONFIG..."
    mkdir -p `dirname $CONFIG`
    touch "$CONFIG"
    chmod 600 "$CONFIG"
    echo "# Keyringer config file." > "$CONFIG"
    echo "" >> "$CONFIG"
  fi

  keyringer_config_load_preferences
}

# Load config preferences
function keyringer_config_load_preferences {
  # Load custom keyring preferences
  if [ ! -z "$PREFERENCES" ] && [ -f "$PREFERENCES" ]; then
    source "$PREFERENCES"
  elif [ ! -z "$PREFERENCES" ]; then
    touch $PREFERENCES
  fi
}

# Load a parameter from config
function keyringer_config {
  if [ -z "$CONFIG" ]; then
    echo "Your have to set CONFIG variable in the code"
    exit 1
  elif [ -e "$CONFIG" ]; then
    grep -e "^$1=" "$CONFIG" | tail -n 1 | cut -d = -f 2 | sed -e 's/"//g' -e "s/'//g" | sed -e 's/ *#.*$//'
  else
    echo "Config file not found: $CONFIG"
    exit 1
  fi
}

# Return the list of recipients
function keyringer_recipients {
  grep -v '^#' "$1" | grep -v '^$' | awk '{ print "-r " $2 }' | xargs
}

# Check if keyringer has a given action
function keyringer_has_action {
 if [ -z "$ACTIONS" ]; then
   echo "Your have to set ACTIONS variable in the code"
   exit 1
 fi

 if [ -e "$ACTIONS/$1" ] && [ ! -d "$ACTIONS/$1" ]; then
   true
 else
   false
 fi
}

# Execute an action
function keyringer_exec {
  # Setup
  action="$1"
  basedir="$2"
  shift 2

  # Dispatch
  if keyringer_has_action "$action"; then
    "$ACTIONS/$action" "$basedir" $*
    err="$?"
    if [ "$err" != "0" ]; then
      exit "$err"
    fi
  fi
}

# Return a filename with correct extension
function keyringer_filename {
  if [ -z "$1" ]; then
    return
  else
    printf "%s/%s.asc\n" "$(dirname "$1")" "$(basename "$1" .asc)"
  fi
}

# Check if a folder is inside a git repository
function keyringer_is_git {
  if [ -z "$1" ]; then
    false
  elif [ ! -d "$1" ]; then
    false
  elif [ -d "$1/.git" ]; then
    true
  else
    ( cd "$1" && git status &> /dev/null )

    if [ "$?" != "128" ]; then
      true
    else
      false
    fi
  fi
}

# Check the security of a temporary folder
function keyringer_check_tmp {
  local path="$1"
  local mount

  # Mode check
  if [ -z "$path" ] || [ ! -d "$path" ] || [ ! -w "$path" ] || [ ! -x "$path" ]; then
    return 1
  fi

  # Ramdisk check
  mount="`df "$path" | sed -n '$p' | awk '{ print $NF }'`"
  mount -l -t tmpfs | awk '{ print $3 }' | grep -q -e "^$mount$"
}

# Setup a temporary file
function keyringer_set_tmpfile {
  local tmp
  local candidate
  local candidates="$TMPDIR $TMP /tmp /run/shm"

  if [ -z "$BASEDIR" ]; then
    echo "Please set BASEDIR before creating a tmp file"
    exit 1
  fi

  # Ramdisk check
  for candidate in $candidates; do
    if keyringer_check_tmp $candidate; then
      tmp="$candidate/keyringer.`whoami`"
      break
    fi
  done

  # Set base temp folder
  if [ -z "$tmp" ]; then
    echo "WARNING: neither one of $candidates is mounted in a tmpfs/ramdisk, using $BASEDIR/tmp as fallback."
    echo "Make sure that $BASEDIR is atop of an encrypted volume."
    echo "Press any key to continue, Ctrl-C to abort"
    read key
    tmp="$BASEDIR/tmp"

    # Just to be sure
    keyringer_git_ignore 'tmp/*'
  fi

  # Determine template
  if [ -z "$1" ]; then
    template="$tmp/keyringer.XXXXXXXXXX"
  else
    template="$tmp/keyringer.$1.XXXXXXXXXX"
  fi

  mkdir -p "$tmp"

  if [ "$2" == "-d" ]; then
    TMPWORK="$(mktemp -d "$template")"
  else
    TMPWORK="$(mktemp "$template")"
  fi

  if [ "$?" != "0" ]; then
    printf "Error: can't set TMPWORK %s\n" "$TMPWORK"
    exit 1
  fi

  trap "keyringer_unset_tmpfile $TMPWORK; exit" INT TERM EXIT
}

# Shred files
function keyringer_shred {
  local path="$1"
  local tool
  local message="Removing"

  if [ -z "$path" ]; then
    return
  elif [ ! -e "$path" ]; then
    return
  fi

  # Create our test target
  local rmtest="$(mktemp)"

  # Get shred implementation
  if which wipe &> /dev/null; then
    tool="wipe"
  elif which shred &> /dev/null; then
    tool="shred"
  elif rm -P "${rmtest}" &> /dev/null; then
    tool="rm -P"
  else
    # Worst implementation
    message="WARNING $message"
    tool="rm"
  fi

  # Cleanup in case "rm -P" is never called or -P flag is unsupported
  rm -f "${rmtest}"

  echo "$message $path using $tool..."

  if [ -d "$path" ]; then
    if [ "$tool" == "wipe" ] || [ "$tool" == "rm" ] || [ "$tool" == "rm -P" ]; then
      $tool -rf $path
    else
      find $path -type f -exec $tool -uf {} \;
      find -d $path -type d -exec rmdir {} \;
    fi
  else
    if [ "$tool" == "wipe" ] || [ "$tool" == "rm" ] || [ "$tool" == "rm -P" ]; then
      $tool -f "$path"
    else
      $tool -uf "$path"
    fi
  fi
}

# Remove a temporary file
function keyringer_unset_tmpfile {
  if [ -z "$1" ]; then
    echo "No tmp file set"
  fi

  keyringer_shred "$1"

  if [ "$?" != "0" ]; then
    echo "Warning: could not delete file $1. Please delete it manually as it might have sensitive information."
    exit 1
  fi
}

# Add a pattern into gitignore
function keyringer_git_ignore {
  if [ ! -z "$BASEDIR/.gitignore" ]; then
    echo "$1" > "$BASEDIR/.gitignore"
    keyringer_exec git "$BASEDIR" add .gitignore
  else
    if ! grep -q -e "^$1$" "$BASEDIR/.gitignore"; then
      echo "$1" >> "$BASEDIR/.gitignore"
    fi
  fi
}

# Set needed environment variables and do basic checks.
function keyringer_set_env {
  if [ -z "$1" ]; then
    echo "Error: missing arguments for keyringer_set_env"
    exit 1
  fi

  # The first argument tells what the action plans to do with the
  # keyring database: either read, write, readwrite or maintenance.
  if [ "$1" != "read" ] && [ "$1" != "write" ] && [ "$1" != "readwrite" ] && [ "$1" != "maintenance" ]; then
    echo "Error: first keyringer_set_env argument must be either read, write or readwrite"
    exit 1
  fi

  ACTIONS="`dirname $0`"
  BASENAME="`basename $0`"
  KEYRINGER_MODE="$1"
  BASEDIR="$2"
  SUBCOMMAND="$3"
  KEYDIR="$BASEDIR/keys"
  RECIPIENTS_BASE="config/recipients"
  RECIPIENTS="$BASEDIR/$RECIPIENTS_BASE"
  OPTIONS="$BASEDIR/config/options"
  VERSION_INFO="$BASEDIR/config/version"

  if [ -z "$BASEDIR" ]; then
    keyringer_action_usage
    exit 1
  fi

  if [ ! -e "$RECIPIENTS" ]; then
    echo "No recipient config was found"
    exit 1
  fi

  if [ -z "$EDITOR" ]; then
    if type sensible-editor > /dev/null 2>&1 ; then
      EDITOR=sensible-editor
    elif type editor > /dev/null 2>&1 ; then
      EDITOR=editor
    else
      echo "You have to set EDITOR env variable"
      exit 1
    fi
  fi

  # Avoid viminfo, see https://keyringer.pw/trac/ticket/50
  if $EDITOR --help 2>&1 | grep -q -e "^VIM"; then
    if ! echo $EDITOR | grep -q -- "-i NONE"; then
      EDITOR="$EDITOR -S $SHARE/editors/vim"
    fi
  fi

  if [ ! -f "$OPTIONS" ]; then
    echo "No option config was found"
    exit 1
  fi

  if [ ! -z "$KEYID" ]; then
    GPG="gpg --quiet -u $KEYID"
  else
    GPG="gpg --quiet"
  fi

  # Check keyring config version
  keyringer_check_version

  # Upgrade configuration
  keyringer_upgrade

  # Check repository integrity
  if [ "$BASENAME" == "check" ]; then
    keyringer_check_repository
  fi

  # Check recipients file
  keyringer_check_recipients $SUBCOMMAND

  # Ensure that keydir exists
  mkdir -p "$KEYDIR" && chmod 700 "$KEYDIR"
}

# Configuration version tracking to help keyring upgrades
function keyringer_check_version {
  if [ "$KEYRINGER_CHECK_VERSION" == "false" ]; then
    if [ -f "$VERSION_INFO" ]; then
      VERSION="`cat $VERSION_INFO`"
    else
      VERSION=""
    fi

    return
  fi

  if [ ! -f "$VERSION_INFO" ]; then
    echo "Configuration version file not found, trying to pull from remotes..."
    # Do not use keyringer_exec as it would trigger keyringer_check_version again
    ( cd "$BASEDIR" && git pull )

    if [ ! -f "$VERSION_INFO" ]; then
      echo "Creating configuration version file..."
      echo 0 > "$VERSION_INFO"
      if keyringer_is_git "$BASEDIR"; then
        keyringer_exec git "$BASEDIR" add config/version
        echo "Pushing configuration version file to remotes..."
        for remote in "$BASEDIR/.git/refs/remotes/*"; do
          keyringer_exec git "$BASEDIR" push $remote master
        done
      fi
    fi
  fi

  VERSION="`cat $VERSION_INFO`"

  # Check if config version is supported by keyringer
  if [ "$VERSION" != "$CONFIG_VERSION" ]; then
    echo "Configuration version differs from keyringer version, trying to pull from remotes"
    # Do not use keyringer_exec as it would trigger keyringer_check_version again
    ( cd "$BASEDIR" && git pull )

    if [ "$VERSION" != "$CONFIG_VERSION" ]; then
      NEWEST="`echo -e "$VERSION\n$CONFIG_VERSION" | sort -V | tail -n 1`"
      if [ "$NEWEST" == "$VERSION" ]; then
        echo "Fatal: config version: $CONFIG_VERSION / config version: $VERSION"
        echo "Please upgrade your keyringer application"
        exit 1
      fi
    fi
  fi
}

# Configuration upgrades
function keyringer_upgrade {
  # Variable used to hold applied version upgrades
  local version="$VERSION"

  if [ "$KEYRINGER_CHECK_VERSION" == "false" ]; then
    return
  fi

  # Upgrade 0.1
  if [ "$version" == "0" ]; then
    if [ ! -d "$RECIPIENTS" ]; then
      echo "Converting recipients to the new scheme..."
      mv $RECIPIENTS $RECIPIENTS.tmp
      mkdir $RECIPIENTS
      mv $RECIPIENTS.tmp $RECIPIENTS/default
      keyringer_exec git "$BASEDIR" add $RECIPIENTS_BASE/default
      keyringer_exec git "$BASEDIR" commit -m "Config-upgrade-0.1"
    fi

    # Done 0.1 upgrade
    echo "0.1" > $VERSION_INFO
    version="0.1"
  fi

  # Upgrade 0.X
  #if [ "$version" == "0.1" ]; then
  #  echo "Upgrading to 0.X config format..."
  #
  #  # Done 0.X upgrade
  #  echo "0.X" > $VERSION_INFO
  #  version="0.X"
  #fi

  # Update version information
  if [ "$CONFIG_VERSION" != "$VERSION" ]; then
    echo $CONFIG_VERSION > $VERSION_INFO
    keyringer_exec git "$BASEDIR" add config/version
    keyringer_exec git "$BASEDIR" commit -m "Config-update-$CONFIG_VERSION"
    echo "Upgrade to version $CONFIG_VERSION completed, pushing to remotes..."
    for remote in "$BASEDIR/.git/refs/remotes/*"; do
      keyringer_exec git "$BASEDIR" push $remote master
    done
  fi
}

# Get an option
#
# Given that options are shared among users through the
# repository, we can't just "source $OPTIONS" as we would
# be opening a simple arbitrary code execution hole.
#
# TODO
function keyringer_get_option {
  false
}

# Get a file argument
function keyringer_get_file {
  FILE="$(keyringer_filename "$RELATIVE_PATH/$1")"

  if [ ! -f "$KEYDIR/$FILE" ]; then
    # Try to find a similar file
    FILE=""
    count=0
    candidates=(`keyringer_exec find "$BASEDIR" | grep -i "$1" | grep -e '.asc$'`)

    if [ ! -z "$candidates" ]; then
      if [ ! -z "$1" ]; then
        echo "Could not find exact match for \"$1\""
      fi

      echo "Choose one of the following or type a pattern:"
      echo ""

      for candidate in ${candidates[@]}; do
        echo -e "\t[$count] $candidate"
        let count++
      done

      echo ""
      read -p "Enter option (Ctrl-C to abort): " option

      if [[ "$option" =~ ^[0-9]+$ ]] && [ ! -z "${candidates[$option]}" ]; then
        FILE="$(keyringer_filename "$RELATIVE_PATH/${candidates[$option]}")"
      elif [ ! -z "$option" ]; then
        keyringer_get_file $option
      fi
    else
      echo "Nothing matches $option, try again."
      keyringer_get_file
    fi
  fi

  # Probably Ctrl-D was hit
  if [ -z "$FILE" ]; then
    echo ""
    exit
  fi
}

# Get a new file argument
function keyringer_get_new_file {
  # File must not contain spaces
  if [ ! -z "$2" ] ; then
    FILE="`echo "$*" | sed -e 's/ /_/g'`"
  else
    FILE="$1"
  fi

  # Sanitize and complete file name
  FILE="`echo $FILE | sed -e 's/[^A-Za-z0-9@.\/\-]/_/g'`"

  # Warn user about file name change
  if [ "`basename "$*"`" != "`basename $FILE`" ]; then
    echo "Sanitizing destination filename to `basename $FILE`"
  fi

  # Complete file name
  FILE="$RELATIVE_PATH/$(keyringer_filename "$FILE")"

  if [ -z "$*" ]; then
    keyringer_action_usage
    exit 1
  fi
}

# Get a command argument
function keyringer_get_command {
  # Aditional parameters
  COMMAND="$1"

  if [ -z "$COMMAND" ]; then
    keyringer_action_usage command
    exit 1
  fi
}

# Run the action usage
function keyringer_action_usage {
  if [ "`type -t "keyringer_usage_$BASENAME"`" == "function" ]; then
    # Use custom action usage
    "keyringer_usage_$BASENAME"
  else
    # Default usage
    if [ "$1" == "command" ]; then
      echo "Usage: keyringer <keyring> $BASENAME <command> [arguments]"
    else
      echo "Usage: keyringer <keyring> $BASENAME <file>"
    fi
  fi
}

# Return available actions
function keyringer_show_actions {
  ls -C $ACTIONS
}

# Usage
function keyringer_usage {
  # are we're using an `ls` that supports `--color`?
  if ls --version > /dev/null 2>&1; then
    local keyrings="$(ls --color=never `dirname $CONFIG` | sed -e 's/config//' | xargs)"
  else
    local keyrings="$(ls `dirname $CONFIG` | sed -e 's/config//' | xargs)"
  fi

  printf "Keyringer $KEYRINGER_VERSION\n"
  printf "Usage: keyringer <keyring> <action> [arguments]\n\n"

  # Display only when not in a keyring context
  if [ ! -z "$keyrings" ] && [ -z "$1" ]; then
    printf "Available keyrings: %s \n" "$keyrings"
  fi

  # Show available actions
  printf "Available actions: \n\n"
  if [ ! -z "$keyrings" ] && [ -z "$1" ]; then
    printf "\tinit <path> [remote]\n" $BASENAME
  fi
  # \t is a GNU extension
  # https://stackoverflow.com/questions/8400602/sed-replace-literal-tab
  keyringer_show_actions | sed -e "`printf 's/^/\t/'`"
  printf "\n"
}

# Check repository integrity
function keyringer_check_repository {
  # Check if it's a git repository
  if [ ! -d "$BASEDIR/.git" ]; then
    echo "Fatal: not a git repository: $BASEDIR"
    exit 1
  fi

  # Git maintenance operations
  echo "Running git maintenance operations..."
  keyringer_exec git "$BASEDIR" fsck
  keyringer_exec git "$BASEDIR" gc
  echo ""

  # Sync the repository
  if [ "`keyringer_exec git "$BASEDIR" remote | wc -l`" != "0" ]; then
    echo "Syncing git repository..."
    keyringer_exec git "$BASEDIR" pull
    echo ""
  fi
}

# Receive keys from keyservers
# TODO: gpg-maintenance trickery
# TODO: should be controlled by user preference
function keyringer_recv_keys {
  local recipient="$1"

  echo "Trying to receive missing key $recipient..."
  gpg --batch --recv-keys "$recipient"
}

# Refresh keys from keyserver
# TODO: gpg-maintenance trickery
# TODO: should be controlled by user preference
function keyringer_refresh_keys {
  local recipient="$1"

  echo "Trying to refresh key $recipient..."
  gpg --batch --recv-keys "$recipient"
}

# Check recipient size
function keyringer_check_recipient_size {
  local recipient="$1"
  local size=$(echo "$recipient" | wc -c)

  if (( $size < 41 )); then
    echo "Fatal: please set the full OpenPGP fingerprint for key ID $recipient:"
    cat <<-EOF

Please provide a full OpenPGP fingerprint, for example:

  john@doe.com ABCD1234ABCD12345678ABCD1234ABCD12345678

Short key ids (for example, DEADBEEF or DECAF123) are not allowed in
recipient files because they are easy to spoof. Researchers have proven
that it is possible to build fake keys to match any possible short key
id by using a few gigabytes of disk space, and a day of computation on
common hardware.

Otherwise, the encryption can be broken, if someone spoofs a short key
id, and causes a participant in a keyringer repository to encrypt
secrets to a fake key.
EOF
   exit 1
 fi
}

# Check recipients
function keyringer_check_recipients {
  # Shall we check recipients?
  if [ "$KEYRINGER_CHECK_RECIPIENTS" == "false" ]; then
    return
  fi

  # Local variables
  local processed=":"

  # Check if recipients file is empty.
  if [ "`grep -vE "^#|^$" "$RECIPIENTS"/* | wc -l`" == 0 ] && [ "$SUBCOMMAND" != "edit" ]; then
    echo "Fatal: no recipients configured for this keyring."
    echo "Please edit your recipients file first."
    exit 1
  fi

  # Check recipients header for updates.
  if grep -qe ' XXXXXXXX$' "$RECIPIENTS"/*; then
    echo "Updating recipients file..."
    sed -i -e 's/ XXXXXXXX$/ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/' "$RECIPIENTS"/*
  fi

  #if [ "$1" == "edit" ]; then
  #  # Don't do the other checks at edit mode.
  #  return
  #fi

  for recipient in $(cat "$RECIPIENTS"/* | grep -v '^#' | awk '{ print $2 }'); do
    # Process a recipient just once
    if echo $processed | grep -q "$recipient:"; then
      continue
    else
      processed="$processed$recipient:"
    fi

    # Check recipient size
    keyringer_check_recipient_size "$recipient"

    # Check if key is present
    keyringer_check_recipient_key "$recipient"

    # Refresh keys
    if [ "$BASENAME" == "check" ] && [ "$refresh" != "no" ]; then
      keyringer_refresh_keys "$recipient"
      echo ""
    fi

    # Check key expiration
    keyringer_check_expiration "$recipient"
  done
}

# Check if a key is present
function keyringer_check_recipient_key {
  local recipient="$1"

  gpg --list-key "$recipient" &> /dev/null
  if [ "$?" != "0" ]; then
    if [ "$BASENAME" == "check" ]; then
      refresh="no"
      keyringer_recvs_keys "$recipient"
      if [ "$?" != 0 ]; then
        echo "Error fetching $recipient from keyservers."
        continue
      fi
      echo ""
    else
      echo "Fatal: no such key $recipient on your GnuPG keyring."
      echo "Please retrieve this key yourself or fix the recipient file."

      exit 1
    fi
  fi
}

# Check key expiration
function keyringer_check_expiration {
  # Variables
  local recipient="$1"
  local not_expired="0"

  # Current date
  seconds="`date +%s`"

  # Check the main key
  expiry="`gpg --with-colons --fixed-list-mode --list-keys "$recipient" | grep ^pub | head -n1 | cut -d : -f 7`"

  # TODO: Time to expire can be configured via repository options.
  ahead="$((86400 * 30 + $seconds))"

  # Check if key is expired
  if [ ! -z "$expiry" ] && [[ "$seconds" -gt "$expiry" ]]; then
    echo -n "Warning: primary key for $recipient expired on `date --date="@$expiry"`"

    if [ "$KEYRINGER_MODE" == "write" ] || [ "$KEYRINGER_MODE" == "readwrite" ]; then
      echo ", aborting."
      exit 1
    fi

    echo ""
    return 1
  fi

  # Check if key is about to expire
  # TODO: Users can be alerted by mail if configured by user preferences.
  # TODO: Outgoing emails can be encrypted.
  if [ "$BASENAME" == "check" ] && [ ! -z "$expiry" ] && [[ "$ahead" -gt "$expiry" ]]; then
    echo "Warning: key $recipient will expire soon, on `date --date="@$expiry"`"
  fi

  # Check the subkeys
  local subkey=""
  for subkey in $(gpg --with-colons --fixed-list-mode --list-keys "$recipient" | grep ^sub); do
    local expiry=$(cut -d : -f 7 <<< "$subkey")

    if [[ -z "$expiry" ]]; then
      not_expired=1
    fi

    if [[ "$seconds" -lt "$expiry" ]]; then
      not_expired="1"

      if [[ "$ahead" -gt "$expiry" ]] && [ "$BASENAME" == "check" ]; then
        echo "Warning: subkey from $recipient will expire soon, on `date --date="@$expiry"`"
      fi
    fi
  done

  # All subkeys are expired
  if [ ! -z "$subkey" ] && [ "$not_expired" != "1" ]; then
    echo -n "Warning: key $recipient has no keys suitable for encryption: all subkeys expired."

    if [ "$KEYRINGER_MODE" == "write" ] || [ "$KEYRINGER_MODE" == "readwrite" ]; then
      echo ", aborting."
      exit 1
    fi

    echo ""
    return 1
  fi
}

# Set recipients
function keyringer_set_recipients {
  if [ -z "$1" ]; then
    keyringer_set_default_recipients
  else
    candidate="$1"
    candidate_no_extension="`echo $1 | sed -e 's/.asc$//'`"

    # Find the first matching recipient
    while [ ! -z "$candidate" ] && [ "$candidate" != "." ] && [ "$candidate" != "/" ] && [ "$candidate" != "/." ]; do
      if [ -e "$RECIPIENTS/$candidate" ]; then
        RECIPIENTS_FILE="$RECIPIENTS/$candidate"
        RECIPIENTS_FILE_BASE="$RECIPIENTS_BASE/$candidate"
        return
      elif [ -e "$RECIPIENTS/$candidate_no_extension" ]; then
        RECIPIENTS_FILE="$RECIPIENTS/$candidate_no_extension"
        RECIPIENTS_FILE_BASE="$RECIPIENTS_BASE/$candidate_no_extension"
        return
      fi

      candidate="`dirname $candidate`"
    done

    keyringer_set_default_recipients "$1"

  fi
}

# Set default recipients
function keyringer_set_default_recipients {
  if [ -e "$RECIPIENTS/default" ]; then
    RECIPIENTS_FILE="$RECIPIENTS/default"
    RECIPIENTS_FILE_BASE="$RECIPIENTS_BASE/default"
  else
    echo "Fatal: no suitable recipient file found for path $1"
    exit 1
  fi
}

# Set a new recipient, avoid file checks
function keyringer_set_new_recipients {
  if [ -z "$1" ]; then
    keyringer_set_default_recipients
  else
    RECIPIENTS_FILE="$RECIPIENTS/$1"
    RECIPIENTS_FILE_BASE="$RECIPIENTS_BASE/$1"
  fi
}

# Create a new recipients file
function keyringer_create_new_recipients {
  local recipients="$1"
  local recipient
  local key
  local uid
  local fpr

  if [ ! -e "$recipients" ]; then
    mkdir -p "`dirname $recipients`"
    echo "# Use entries in the form of 'john@doe.com XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'" > "$1"
    echo "" >> "$recipients"

    # Try to get an initial recipient
    if [ -e "$HOME/.gnupg/gpg.conf" ]; then
      recipient="`grep -e "^default-key" ~/.gnupg/gpg.conf | cut -d ' ' -f 2`"

      if [ ! -z "$recipient" ]; then
        key="`gpg --fingerprint --with-colons $recipient 2> /dev/null`"

        if [ "$?" == "0" ]; then
          fpr="`echo "$key" | grep -e '^fpr:' | head -1 | cut -d : -f 10`"
          uid="`echo "$key" | grep -e '^uid:' | head -1 | cut -d : -f 10 | sed -e 's|^[^<]*<||' -e 's|>$||'`"

          if [ ! -z "$uid" ] && [ ! -z "$fpr" ]; then
            echo "Default key $fpr ($uid) found at ~/.gnupg/gpg.conf, using as initial recipient."
            echo "$uid $fpr" >> "$recipients"
          fi
        fi
      fi
    fi
  fi
}

# Setup environment
if [ "$(basename "$0")" != "keyringer" ]; then
  keyringer_config_load_preferences
  keyringer_set_env $*
fi