3 * Command-line encryption tool
5 * (c) 2004 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of Catacomb.
12 * Catacomb is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Library General Public License as
14 * published by the Free Software Foundation; either version 2 of the
15 * License, or (at your option) any later version.
17 * Catacomb is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU Library General Public License for more details.
22 * You should have received a copy of the GNU Library General Public
23 * License along with Catacomb; if not, write to the Free
24 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
28 /*----- Header files ------------------------------------------------------*/
30 #define _FILE_OFFSET_BITS 64
39 #include <mLib/base64.h>
40 #include <mLib/dstr.h>
41 #include <mLib/mdwopt.h>
42 #include <mLib/quis.h>
43 #include <mLib/report.h>
56 /*----- Static variables --------------------------------------------------*/
58 static const char *keyring
= "keyring";
60 /*----- Data format -------------------------------------------------------*/
64 * The encrypted message is divided into chunks, each preceded by a two-octet
65 * length. The chunks don't need to be large -- the idea is that we can
66 * stream the chunks in and out.
68 * The first chunk is a header. It contains the decryption key-id, and maybe
69 * the verification key-id if the message is signed.
71 * Next comes the key-encapsulation chunk. This is decrypted in some
72 * KEM-specific way to yield a secret hash. The hash is expanded using an
73 * MGF (or similar) to make a symmetric encryption and MAC key.
75 * If the message is signed, there comes a signature chunk. The signature is
76 * on the header and key-encapsulation chunks, and further output of the MGF.
77 * This means that the recipient can modify the message and still have a
78 * valid signature, so it's not useful for proving things to other people;
79 * but it also means that the recipient knows that the message is from
80 * someone who knows the hash, which limits the possiblities to (a) whoever
81 * encrypted the message (good!) and (b) whoever knows the recipient's
84 * Then come message chunks. Each one begins with a MAC over an implicit
85 * sequence number and the ciphertext. The final chunk's ciphertext is
86 * empty; no other chunk is empty. Thus can the correct end-of-file be
90 /*----- Chunk I/O ---------------------------------------------------------*/
92 static void chunk_write(enc
*e
, buf
*b
)
98 if (e
->ops
->write(e
, l
, 2) ||
99 e
->ops
->write(e
, BBASE(b
), BLEN(b
)))
100 die(EXIT_FAILURE
, "error writing output: %s", strerror(errno
));
103 static void chunk_read(enc
*e
, dstr
*d
, buf
*b
)
110 if (e
->ops
->read(e
, l
, 2) != 2)
114 if (e
->ops
->read(e
, d
->buf
, n
) != n
)
117 buf_init(b
, d
->buf
, d
->len
);
121 if (!errno
) die(EXIT_FAILURE
, "unexpected end-of-file on input");
122 else die(EXIT_FAILURE
, "error reading input: %s", strerror(errno
));
125 /*----- Encryption --------------------------------------------------------*/
127 static int encrypt(int argc
, char *argv
[])
129 const char *fn
, *of
= 0, *kn
= "ccrypt", *skn
= 0;
132 const char *ef
= "binary";
157 #define f_progress 4u
160 static const struct option opt
[] = {
161 { "key", OPTF_ARGREQ
, 0, 'k' },
162 { "sign-key", OPTF_ARGREQ
, 0, 's' },
163 { "armour", 0, 0, 'a' },
164 { "armor", 0, 0, 'a' },
165 { "format", OPTF_ARGREQ
, 0, 'f' },
166 { "output", OPTF_ARGREQ
, 0, 'o' },
167 { "progress", 0, 0, 'p' },
168 { "nocheck", 0, 0, 'C' },
171 i
= mdwopt(argc
, argv
, "k:s:af:o:pC", opt
, 0, 0, 0);
174 case 'k': kn
= optarg
; break;
175 case 's': skn
= optarg
; break;
176 case 'a': ef
= "pem"; break;
177 case 'f': ef
= optarg
; break;
178 case 'o': of
= optarg
; break;
179 case 'p': f
|= f_progress
; break;
180 case 'C': f
|= f_nocheck
; break;
181 default: f
|= f_bogus
; break;
184 if (argc
- optind
> 1 || (f
& f_bogus
))
185 die(EXIT_FAILURE
, "Usage: encrypt [-OPTIONS] [FILE]");
187 if (key_open(&kf
, keyring
, KOPEN_READ
, key_moan
, 0))
188 die(EXIT_FAILURE
, "can't open keyring `%s'", keyring
);
189 if ((k
= key_bytag(&kf
, kn
)) == 0)
190 die(EXIT_FAILURE
, "key `%s' not found", kn
);
191 if (skn
&& (sk
= key_bytag(&kf
, skn
)) == 0)
192 die(EXIT_FAILURE
, "key `%s' not found", skn
);
194 if ((eo
= getenc(ef
)) == 0)
195 die(EXIT_FAILURE
, "encoding `%s' not found", ef
);
197 fn
= optind
< argc ? argv
[optind
++] : "-";
198 if (strcmp(fn
, "-") == 0)
200 else if ((fp
= fopen(fn
, "rb")) == 0) {
201 die(EXIT_FAILURE
, "couldn't open file `%s': %s",
202 fn
, strerror(errno
));
205 if (!of
|| strcmp(of
, "-") == 0)
207 else if ((ofp
= fopen(of
, eo
->wmode
)) == 0) {
208 die(EXIT_FAILURE
, "couldn't open file `%s' for output: %s",
209 of
, strerror(errno
));
214 e
= initenc(eo
, ofp
, "CATCRYPT ENCRYPTED MESSAGE");
215 km
= getkem(k
, "cckem", 0);
216 if (!(f
& f_nocheck
) && (err
= km
->ops
->check(km
)) != 0)
217 moan("key %s fails check: %s", d
.buf
, err
);
221 s
= getsig(sk
, "ccsig", 1);
222 if ((err
= s
->ops
->check(s
)) != 0)
223 moan("key %s fails check: %s", d
.buf
, err
);
226 /* --- Build the header chunk --- */
229 dstr_ensure(&d
, 256);
230 buf_init(&b
, d
.buf
, 256);
231 buf_putu32(&b
, k
->id
);
232 if (sk
) buf_putu32(&b
, sk
->id
);
234 if (s
) GH_HASHBUF16(s
->h
, BBASE(&b
), BLEN(&b
));
237 /* --- Build the KEM chunk --- */
240 if (setupkem(km
, &d
, &cx
, &c
, &m
))
241 die(EXIT_FAILURE
, "failed to encapsulate key");
242 buf_init(&b
, d
.buf
, d
.len
);
244 if (s
) GH_HASHBUF16(s
->h
, BBASE(&b
), BLEN(&b
));
247 /* --- Write the signature chunk --- */
250 GC_ENCRYPT(cx
, 0, bb
, 1024);
251 GH_HASH(s
->h
, bb
, 1024);
253 if ((en
= s
->ops
->doit(s
, &d
)) != 0)
254 die(EXIT_FAILURE
, "error creating signature: %s", key_strerror(en
));
255 buf_init(&b
, d
.buf
, d
.len
);
260 /* --- Now do the main crypto --- */
262 if (f
& f_progress
) {
263 if (fprogress_init(&ff
, fn
, fp
)) {
264 die(EXIT_FAILURE
, "failed to initialize progress display: %s",
269 assert(GC_CLASS(c
)->blksz
<= sizeof(bb
));
270 dstr_ensure(&d
, sizeof(bb
) + GM_CLASS(m
)->hashsz
);
272 chsz
= MASK16
- GM_CLASS(m
)->hashsz
;
277 if (GC_CLASS(c
)->blksz
) {
278 GC_ENCRYPT(cx
, 0, bb
, GC_CLASS(c
)->blksz
);
281 n
= fread(bb
, 1, chsz
, fp
);
283 if (f
& f_progress
) fprogress_update(&ff
, n
);
284 buf_init(&b
, d
.buf
, d
.sz
);
285 tag
= buf_get(&b
, GM_CLASS(m
)->hashsz
);
287 assert(tag
); assert(ct
);
288 GC_ENCRYPT(c
, bb
, ct
, n
);
295 /* --- Final terminator packet --- */
297 buf_init(&b
, d
.buf
, d
.sz
);
298 tag
= buf_get(&b
, GM_CLASS(m
)->hashsz
);
304 /* --- All done --- */
306 if (f
& f_progress
) fprogress_done(&ff
);
314 if (fp
!= stdin
) fclose(fp
);
325 /*---- Decryption ---------------------------------------------------------*/
327 static int decrypt(int argc
, char *argv
[])
329 const char *fn
, *of
= 0;
330 FILE *ofp
= 0, *rfp
= 0;
332 const char *ef
= "binary";
359 #define f_progress 8u
362 static const struct option opt
[] = {
363 { "armour", 0, 0, 'a' },
364 { "armor", 0, 0, 'a' },
365 { "buffer", 0, 0, 'b' },
366 { "verbose", 0, 0, 'v' },
367 { "quiet", 0, 0, 'q' },
368 { "nocheck", 0, 0, 'C' },
369 { "format", OPTF_ARGREQ
, 0, 'f' },
370 { "output", OPTF_ARGREQ
, 0, 'o' },
371 { "progress", 0, 0, 'p' },
374 i
= mdwopt(argc
, argv
, "abf:o:pqvC", opt
, 0, 0, 0);
377 case 'a': ef
= "pem"; break;
378 case 'b': f
|= f_buffer
; break;
379 case 'v': verb
++; break;
380 case 'q': if (verb
) verb
--; break;
381 case 'C': f
|= f_nocheck
; break;
382 case 'f': ef
= optarg
; break;
383 case 'o': of
= optarg
; break;
384 case 'p': f
|= f_progress
; break;
385 default: f
|= f_bogus
; break;
388 if (argc
- optind
> 1 || (f
& f_bogus
))
389 die(EXIT_FAILURE
, "Usage: decrypt [-OPTIONS] [FILE]");
391 if ((eo
= getenc(ef
)) == 0)
392 die(EXIT_FAILURE
, "encoding `%s' not found", ef
);
394 fn
= optind
< argc ? argv
[optind
++] : "-";
395 if (strcmp(fn
, "-") == 0)
397 else if ((fp
= fopen(fn
, eo
->rmode
)) == 0) {
398 die(EXIT_FAILURE
, "couldn't open file `%s': %s",
399 fn
, strerror(errno
));
402 if (key_open(&kf
, keyring
, KOPEN_READ
, key_moan
, 0))
403 die(EXIT_FAILURE
, "can't open keyring `%s'", keyring
);
405 e
= initdec(eo
, fp
, checkbdry
, "CATCRYPT ENCRYPTED MESSAGE");
407 if (f
& f_progress
) {
408 if (fprogress_init(&ff
, fn
, fp
)) {
409 die(EXIT_FAILURE
, "failed to initialize progress display: %s",
414 /* --- Read the header chunk --- */
416 chunk_read(e
, &d
, &b
);
418 fprogress_update(&ff
, BLEFT(&b
)*e
->ops
->ncook
/e
->ops
->nraw
);
419 if (buf_getu32(&b
, &id
)) {
420 if (f
& f_progress
) fprogress_done(&ff
);
421 if (verb
) printf("FAIL malformed header: missing keyid\n");
424 if ((k
= key_byid(&kf
, id
)) == 0) {
425 if (f
& f_progress
) fprogress_done(&ff
);
426 if (verb
) printf("FAIL key id %08lx not found\n", (unsigned long)id
);
430 if (buf_getu32(&b
, &id
)) {
431 if (f
& f_progress
) fprogress_done(&ff
);
432 if (verb
) printf("FAIL malformed header: missing signature keyid\n");
435 if ((sk
= key_byid(&kf
, id
)) == 0) {
436 if (f
& f_progress
) fprogress_done(&ff
);
437 if (verb
) printf("FAIL key id %08lx not found\n", (unsigned long)id
);
442 if (f
& f_progress
) fprogress_done(&ff
);
443 if (verb
) printf("FAIL malformed header: junk at end\n");
447 s
= getsig(sk
, "ccsig", 0);
448 if (!(f
& f_nocheck
) && verb
&& (err
= s
->ops
->check(s
)) != 0) {
451 printf("WARN verification key %s fails check: %s\n", d
.buf
, err
);
453 GH_HASHBUF16(s
->h
, BBASE(&b
), BSZ(&b
));
456 /* --- Find the key --- */
458 km
= getkem(k
, "cckem", 1);
460 /* --- Read the KEM chunk --- */
462 chunk_read(e
, &d
, &b
);
464 fprogress_update(&ff
, BLEFT(&b
)*e
->ops
->ncook
/e
->ops
->nraw
);
465 if (setupkem(km
, &d
, &cx
, &c
, &m
)) {
466 if (f
& f_progress
) fprogress_done(&ff
);
467 if (verb
) printf("FAIL failed to decapsulate key\n");
470 if (s
) GH_HASHBUF16(s
->h
, d
.buf
, d
.len
);
472 /* --- Verify the signature, if there is one --- */
476 dstr_ensure(&d
, 1024);
477 GC_ENCRYPT(cx
, 0, d
.buf
, 1024);
478 GH_HASH(s
->h
, d
.buf
, 1024);
479 chunk_read(e
, &d
, &b
);
481 fprogress_update(&ff
, BLEFT(&b
)*e
->ops
->ncook
/e
->ops
->nraw
);
482 if (s
->ops
->doit(s
, &d
)) {
483 if (f
& f_progress
) fprogress_done(&ff
);
484 if (verb
) printf("FAIL signature verification failed\n");
490 if (f
& f_progress
) fprogress_clear(&ff
);
491 printf("INFO good-signature %s\n", d
.buf
);
495 if (f
& f_progress
) fprogress_clear(&ff
);
496 printf("INFO no-signature\n");
499 /* --- Now decrypt the main body --- */
501 if (!of
|| strcmp(of
, "-") == 0) {
505 if (!(f
& f_buffer
)) {
506 if ((ofp
= fopen(of
, "wb")) == 0) {
507 if (f
& f_progress
) fprogress_done(&ff
);
508 die(EXIT_FAILURE
, "couldn't open file `%s' for output: %s",
509 of
, strerror(errno
));
512 } else if ((rfp
= tmpfile()) == 0) {
513 if (f
& f_progress
) fprogress_done(&ff
);
514 die(EXIT_FAILURE
, "couldn't create temporary file: %s", strerror(errno
));
518 dstr_ensure(&d
, GC_CLASS(c
)->blksz
);
521 if (GC_CLASS(c
)->blksz
) {
522 GC_ENCRYPT(cx
, 0, d
.buf
, GC_CLASS(c
)->blksz
);
528 chunk_read(e
, &d
, &b
);
530 fprogress_update(&ff
, BLEFT(&b
)*e
->ops
->ncook
/e
->ops
->nraw
);
531 if ((tag
= buf_get(&b
, GM_CLASS(m
)->hashsz
)) == 0) {
532 if (f
& f_progress
) fprogress_done(&ff
);
533 if (verb
) printf("FAIL bad ciphertext chunk: no tag\n");
536 GH_HASH(h
, BCUR(&b
), BLEFT(&b
));
537 if (memcmp(tag
, GH_DONE(h
, 0), GM_CLASS(m
)->hashsz
) != 0) {
538 if (f
& f_progress
) fprogress_done(&ff
);
540 printf("FAIL bad ciphertext chunk: authentication failure\n");
546 GC_DECRYPT(c
, BCUR(&b
), BCUR(&b
), BLEFT(&b
));
547 if (fwrite(BCUR(&b
), 1, BLEFT(&b
), rfp
) != BLEFT(&b
)) {
548 if (f
& f_progress
) fprogress_done(&ff
);
549 if (verb
) printf("FAIL error writing output: %s\n", strerror(errno
));
554 if (f
& f_progress
) fprogress_done(&ff
);
555 if (fflush(rfp
) || ferror(rfp
)) {
556 if (verb
) printf("FAIL error writing output: %s\n", strerror(errno
));
560 if (!ofp
&& (ofp
= fopen(of
, "wb")) == 0) {
561 die(EXIT_FAILURE
, "couldn't open file `%s' for output: %s",
562 of
, strerror(errno
));
565 if (f
& f_progress
) fprogress_init(&ff
, "copying buffer", rfp
);
567 dstr_ensure(&d
, 65536);
568 if (verb
&& ofp
== stdout
) printf("DATA\n");
570 n
= fread(d
.buf
, 1, d
.sz
, rfp
);
572 if (f
& f_progress
) fprogress_update(&ff
, n
);
573 if (fwrite(d
.buf
, 1, n
, ofp
) < n
) {
574 if (f
& f_progress
) fprogress_done(&ff
);
575 die(EXIT_FAILURE
, "error writing output: %s", strerror(errno
));
578 if (f
& f_progress
) fprogress_done(&ff
);
579 if (ferror(rfp
) || fclose(rfp
))
580 die(EXIT_FAILURE
, "error unbuffering output: %s", strerror(errno
));
584 if (verb
&& ofp
!= stdout
)
585 printf("OK decrypted successfully\n");
586 if (ofp
&& (fflush(ofp
) || ferror(ofp
) || fclose(ofp
)))
587 die(EXIT_FAILURE
, "error writing output: %s", strerror(errno
));
593 if (fp
!= stdin
) fclose(fp
);
604 /*----- Main code ---------------------------------------------------------*/
608 listtab[i].name, listtab[i].name) \
609 LI("Key-encapsulation mechanisms", kem, \
610 kemtab[i].name, kemtab[i].name) \
611 LI("Signature schemes", sig, \
612 sigtab[i].name, sigtab[i].name) \
613 LI("Encodings", enc, \
614 enctab[i].name, enctab[i].name) \
615 LI("Symmetric encryption algorithms", cipher, \
616 gciphertab[i], gciphertab[i]->name) \
617 LI("Hash functions", hash, \
618 ghashtab[i], ghashtab[i]->name) \
619 LI("Message authentication codes", mac, \
620 gmactab[i], gmactab[i]->name)
622 MAKELISTTAB(listtab
, LISTS
)
624 int cmd_show(int argc
, char *argv
[])
626 return (displaylists(listtab
, argv
+ 1));
629 static int cmd_help(int, char **);
631 static cmd cmdtab
[] = {
632 { "help", cmd_help
, "help [COMMAND...]" },
633 { "show", cmd_show
, "show [ITEM...]" },
636 { "encrypt", encrypt
,
637 "encrypt [-apC] [-k TAG] [-s TAG] [-f FORMAT]\n\t\
638 [-o OUTPUT] [FILE]", "\
641 -a, --armour Same as `-f pem'.\n\
642 -f, --format=FORMAT Encode as FORMAT.\n\
643 -k, --key=TAG Use public encryption key named by TAG.\n\
644 -s, --sign-key=TAG Use private signature key named by TAG.\n\
645 -o, --output=FILE Write output to FILE.\n\
646 -p, --progress Show progress on large files.\n\
647 -C, --nocheck Don't check the public key.\n\
649 { "decrypt", decrypt
,
650 "decrypt [-abpqvC] [-f FORMAT] [-o OUTPUT] [FILE]", "\
653 -a, --armour Same as `-f pem'.\n\
654 -b, --buffer Buffer output until we're sure we have it all.\n\
655 -f, --format=FORMAT Decode as FORMAT.\n\
656 -o, --output=FILE Write output to FILE.\n\
657 -p, --progress Show progress on large files.\n\
658 -q, --quiet Produce fewer messages.\n\
659 -v, --verbose Produce more verbose messages.\n\
660 -C, --nocheck Don't check the private key.\n\
665 static int cmd_help(int argc
, char **argv
)
667 sc_help(cmdtab
, stdout
, argv
+ 1);
671 void version(FILE *fp
)
673 pquis(fp
, "$, Catacomb version " VERSION
"\n");
676 static void usage(FILE *fp
)
678 pquis(fp
, "Usage: $ [-k KEYRING] COMMAND [ARGS]\n");
681 void help_global(FILE *fp
)
685 Encrypt and decrypt files.\n\
687 Global command-line options:\n\
689 -h, --help [COMMAND...] Show this help message, or help for COMMANDs.\n\
690 -v, --version Show program version number.\n\
691 -u, --usage Show a terse usage message.\n\
693 -k, --keyring=FILE Read keys from FILE.\n",
699 * Arguments: @int argc@ = number of command line arguments
700 * @char *argv[]@ = vector of command line arguments
702 * Returns: Zero if successful, nonzero otherwise.
704 * Use: Encrypts or decrypts files.
707 int main(int argc
, char *argv
[])
713 /* --- Initialize the library --- */
717 rand_noisesrc(RAND_GLOBAL
, &noise_source
);
718 rand_seed(RAND_GLOBAL
, 160);
720 /* --- Parse options --- */
723 static struct option opts
[] = {
724 { "help", 0, 0, 'h' },
725 { "version", 0, 0, 'v' },
726 { "usage", 0, 0, 'u' },
727 { "keyring", OPTF_ARGREQ
, 0, 'k' },
730 int i
= mdwopt(argc
, argv
, "+hvu k:", opts
, 0, 0, 0);
735 sc_help(cmdtab
, stdout
, argv
+ optind
);
757 if (f
& f_bogus
|| argc
< 1) {
762 /* --- Dispatch to the correct subcommand handler --- */
764 return (findcmd(cmdtab
, argv
[0])->cmd(argc
, argv
));
769 /*----- That's all, folks -------------------------------------------------*/