5 * Simple key management
7 * (c) 1999 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Catacomb.
14 * Catacomb is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * Catacomb is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with Catacomb; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 #ifndef CATACOMB_KEY_H
31 #define CATACOMB_KEY_H
37 /*----- Header files ------------------------------------------------------*/
42 #include <mLib/bits.h>
43 #include <mLib/dstr.h>
44 #include <mLib/hash.h>
47 #ifndef CATACOMB_KEY_ERROR_H
48 # include "key-error.h"
51 #ifndef CATACOMB_KEY_DATA_H
52 # include "key-data.h"
55 #ifndef CATACOMB_GHASH_H
63 /*----- Data structures ---------------------------------------------------*/
65 /* --- Key attributes --- *
67 * Each attribute is stored as a symbol in a symbol table. The value is
68 * the plain (not url-encoded) text to be written to the the file. If the
69 * value is binary data, then by this point it's base-64 encoded.
72 typedef struct key_attr
{
73 sym_base _b
; /* Symbol table data */
74 char *p
; /* Pointer to attribute value */
77 /* --- Main key structure --- *
79 * Each key is stored in two symbol tables, one indexed by keyid, and the
80 * other indexed by type. Because many keys can have the same type, the type
81 * table contains a list of keys, sorted in descending order of expiry.
86 /* --- Hashtable management --- */
88 hash_base _b
; /* Symbol table data */
89 struct key
*next
; /* Next key of the same type */
91 /* --- Basic key attributes --- */
93 uint32 id
; /* Key id used to name it */
94 char *tag
; /* Textual tag name */
95 char *type
; /* Textual key type */
96 time_t exp
, del
; /* Expiry times for keys */
98 /* --- The key data itself --- */
100 key_data
*k
; /* The actual key data */
102 /* --- Other attributes and commentary --- */
104 sym_table a
; /* Hashtable of key attributes */
105 char *c
; /* Any additional comments */
108 /* --- The keys-by-type entries --- */
110 typedef struct key_ref
{
111 sym_base _b
; /* Symbol table data */
112 key
*k
; /* Pointer to first key in list */
115 /* --- A key file --- */
117 typedef struct key_file
{
118 FILE *fp
; /* File pointer open on file */
119 char *name
; /* Filename used to create it */
120 unsigned f
; /* Various useful flags */
121 hash_table byid
; /* Table of keys by keyid */
122 sym_table bytype
; /* Table of keys by type */
123 sym_table bytag
; /* Table of keys by tag */
124 size_t idload
; /* Loading on id table */
127 /* --- Key file flags --- */
129 #define KF_WRITE 1u /* File opened for writing */
130 #define KF_MODIFIED 2u /* File has been modified */
132 /* --- Iterating over keys --- *
134 * Both of these are simple symbol table iterators, but they're made distinct
135 * types for the dubious benefits that type safety brings.
138 typedef struct { hash_iter i
; time_t t
; } key_iter
;
139 typedef struct { sym_iter i
; } key_attriter
;
141 /* --- Key fetching --- */
143 typedef struct key_fetchdef
{
144 char *name
; /* Name of item */
145 size_t off
; /* Offset into target structure */
146 unsigned e
; /* Flags for the item */
147 const struct key_fetchdef
*kf
; /* Substructure pointer */
150 /* --- File opening options --- */
152 #define KOPEN_READ 0u
153 #define KOPEN_WRITE 1u
154 #define KOPEN_MASK 0xff
155 #define KOPEN_NOFILE 0x100
157 /* --- Various other magic numbers --- */
159 #define KEXP_FOREVER ((time_t)-1) /* Never expire this key */
160 #define KEXP_EXPIRE ((time_t)-2) /* Expire this key when unused */
162 /* --- Write error codes --- */
165 KWRITE_OK
, /* Everything went fine */
166 KWRITE_FAIL
= -1, /* Close attempt failed */
167 KWRITE_BROKEN
= -2 /* Key ring needs manual fixing */
170 /* --- Error reporting functions for @key_merge@ and @key_open@ --- */
172 typedef void key_reporter(const char */
*file*/
, int /*line*/,
173 const char */
*err*/
, void */
*p*/
);
175 /* --- Macros for testing expiry --- */
177 #define KEY_EXPIRED(now, exp) \
178 ((exp) == KEXP_EXPIRE || ((exp) != KEXP_FOREVER && (exp) < (now)))
180 /*----- Reading and writing keys and files --------------------------------*/
182 /* --- @key_merge@ --- *
184 * Arguments: @key_file *f@ = pointer to file structure
185 * @const char *file@ = name of file (for error messages)
186 * @FILE *fp@ = file handle to read from
187 * @key_reporter *rep@ = error reporting function
188 * @void *arg@ = argument for function
190 * Returns: Error code (one of the @KERR@ constants).
192 * Use: Reads keys from a file, and inserts them into the file.
195 extern int key_merge(key_file */
*f*/
, const char */
*file*/
, FILE */
*fp*/
,
196 key_reporter */
*rep*/
, void */
*arg*/
);
198 /* --- @key_extract@ --- *
200 * Arguments: @key_file *f@ = pointer to file structure
201 * @key *k@ = key to extract
202 * @FILE *fp@ = file to write on
203 * @const key_filter *kf@ = pointer to key selection block
205 * Returns: Zero if OK, EOF on error.
207 * Use: Extracts a key to an ouptut file.
210 extern int key_extract(key_file */
*f*/
, key */
*k*/
, FILE */
*fp*/
,
211 const key_filter */
*kf*/
);
213 /* --- @key_open@ --- *
215 * Arguments: @key_file *f@ = pointer to file structure to initialize
216 * @const char *file@ = pointer to the file name
217 * @unsigned how@ = opening options (@KOPEN_*@).
218 * @key_reporter *rep@ = error reporting function
219 * @void *arg@ = argument for function
221 * Returns: Zero if it worked, nonzero otherwise.
223 * Use: Opens a key file, reads its contents, and stores them in a
224 * structure. The file is locked appropriately until closed
225 * using @key_close@. On an error, everything is cleared away
226 * tidily. If the file is opened with @KOPEN_WRITE@, it's
227 * created if necessary, with read and write permissions for its
231 extern int key_open(key_file */
*f*/
, const char */
*file*/
, unsigned /*how*/,
232 key_reporter */
*rep*/
, void */
*arg*/
);
234 /* --- @key_discard@ --- *
236 * Arguments: @key_file *f@ = pointer to key file block
240 * Use: Frees all the key data, without writing changes.
243 extern void key_discard(key_file */
*f*/
);
245 /* --- @key_close@ --- *
247 * Arguments: @key_file *f@ = pointer to key file block
249 * Returns: A @KWRITE_@ code indicating how it went.
251 * Use: Frees all the key data, writes any changes. Make sure that
252 * all hell breaks loose if this returns @KWRITE_BROKEN@.
255 extern int key_close(key_file */
*f*/
);
257 /* --- @key_save@ --- *
259 * Arguments: @key_file *f@ = pointer to key file block
261 * Returns: A @KWRITE_@ code indicating how well it worked.
263 * Use: Writes a key file's data back to the actual file. This code
264 * is extremely careful about error handling. It should usually
265 * be able to back out somewhere sensible, but it can tell when
266 * it's got itself into a real pickle and starts leaving well
269 * Callers, please make sure that you ring alarm bells when this
270 * function returns @KWRITE_BROKEN@.
273 extern int key_save(key_file */
*f*/
);
275 /* --- @key_lockfile@ --- *
277 * Arguments: @key_file *f@ = pointer to file structure to initialize
278 * @const char *file@ = pointer to the file name
279 * @unsigned how@ = opening options (@KOPEN_*@).
281 * Returns: Zero if it worked, nonzero otherwise.
283 * Use: Opens a keyfile and stores the information needed for
284 * continued access in the structure.
286 * If the file is opened with @KOPEN_WRITE@, it's created if
287 * necessary with read and write permissions for owner only, and
288 * locked for update while it's open.
290 * This is a system-dependent routine, and only really intended
291 * for the private use of @key_open@.
294 extern int key_lockfile(key_file */
*f*/
, const char */
*file*/
,
297 /*----- Creating and manipulating keys ------------------------------------*/
301 * Arguments: @key_file *f@ = pointer to key file
302 * @uint32 id@ = keyid to set
303 * @const char *type@ = the type of this key
304 * @time_t exp@ = when the key expires
305 * @key *kk@ = where to put the key pointer
307 * Returns: Error code (one of the @KERR@ constants).
309 * Use: Attaches a new key to a key file. You must have a writable
310 * key file for this to work.
312 * The type is a key type string. This interface doesn't care
313 * about how type strings are formatted: it just treats them as
314 * opaque gobs of text. Clients are advised to choose some
315 * standard for representing key types, though.
317 * The expiry time should either be a time in the future, or the
318 * magic value @KEXP_FOREVER@ which means `never expire this
319 * key'. Be careful with `forever' keys. If I were you, I'd
320 * use a more sophisticated key management system than this for
323 * You have to set the actual key yourself.
326 extern int key_new(key_file */
*f*/
, uint32
/*id*/, const char */
*type*/
,
327 time_t /*exp*/, key
**/
*kk*/
);
329 /* --- @key_delete@ --- *
331 * Arguments: @key_file *f@ = pointer to file block
332 * @key *k@ = key to delete
334 * Returns: Error code (one of the @KERR@ constants).
336 * Use: Removes the given key from the list. The key file must be
337 * writable. (Due to the horridness of the data structures,
338 * deleted keys aren't actually removed, just marked so that
339 * they can't be looked up or iterated over. One upshot of
340 * this is that they don't get written back to the file when
344 extern int key_delete(key_file */
*f*/
, key */
*k*/
);
346 /* --- @key_expired@ --- *
348 * Arguments: @key *k@ = pointer to key block
350 * Returns: Zero if the key is OK, nonzero if it's expired.
353 int key_expired(key */
*k*/
);
355 /* --- @key_expire@ --- *
357 * Arguments: @key_file *f@ = pointer to file block
358 * @key *k@ = pointer to key block
360 * Returns: Error code (one of the @KERR@ constants).
362 * Use: Immediately marks the key as expired. It may be removed
363 * immediately, if it is no longer required, and will be removed
364 * by a tidy operation when it is no longer required. The key
365 * file must be writable.
368 extern int key_expire(key_file */
*f*/
, key */
*k*/
);
370 /* --- @key_used@ --- *
372 * Arguments: @key_file *f@ = pointer to key file
373 * @key *k@ = pointer to key block
374 * @time_t t@ = when key can be removed
376 * Returns: Zero if OK, nonzero on failure.
378 * Use: Marks a key as being required until a given time. Even
379 * though the key may expire before then (and won't be returned
380 * by type after that time), it will still be available when
381 * requested explicitly by id. The key file must be writable.
383 * The only (current) reason for failure is attempting to use
384 * a key which can expire for something which can't.
387 extern int key_used(key_file */
*f*/
, key */
*k*/
, time_t /*t*/);
389 /* --- @key_fingerprint@ --- *
391 * Arguments: @key *k@ = the key to fingerprint
392 * @ghash *h@ = the hash to use
393 * @const key_filter *kf@ = filter to apply
395 * Returns: Nonzero if the key slightly matched the filter.
397 * Use: Updates the hash context with the key contents.
400 extern int key_fingerprint(key */
*k*/
, ghash */
*h*/
,
401 const key_filter */
*kf*/
);
403 /*----- Setting and reading attributes ------------------------------------*/
405 /* --- @key_chkident@ --- *
407 * Arguments: @const char *p@ = pointer to a type string
409 * Returns: Zero if OK, -1 on error.
411 * Use: Checks whether an identification component string is OK.
414 extern int key_chkident(const char */
*p*/
);
416 /* --- @key_chkcomment@ --- *
418 * Arguments: @const char *p@ = pointer to a comment string
420 * Returns: Zero if OK, -1 on error.
422 * Use: Checks whether a comment string is OK.
425 extern int key_chkcomment(const char */
*p*/
);
427 /* --- @key_setcomment@ --- *
429 * Arguments: @key_file *f@ = pointer to key file block
430 * @key *k@ = pointer to key block
431 * @const char *c@ = pointer to comment to set, or zero
433 * Returns: Error code (one of the @KERR@ constants).
435 * Use: Replaces the key's current comment with a new one.
438 extern int key_setcomment(key_file */
*f*/
, key */
*k*/
, const char */
*c*/
);
440 /* --- @key_settag@ --- *
442 * Arguments: @key_file *f@ = pointer to key file block
443 * @key *k@ = pointer to key block
444 * @const char *tag@ = pointer to comment to set, or zero
446 * Returns: Error code (one of the @KERR@ constants).
448 * Use: Replaces the key's current tag with a new one.
451 extern int key_settag(key_file */
*f*/
, key */
*k*/
, const char */
*tag*/
);
453 /* --- @key_setkeydata@ --- *
455 * Arguments: @key_file *kf@ = pointer to key file
456 * @key *k@ = pointer to key
457 * @key_data *kd@ = new key data
459 * Returns: Zero on success, or a @KERR_@ error code on failure.
461 * Use: Sets the key data for a key.
464 extern int key_setkeydata(key_file */
*kf*/
, key */
*k*/
, key_data */
*kd*/
);
466 /* --- @key_fulltag@ --- *
468 * Arguments: @key *k@ = pointer to key
469 * @dstr *d@ = pointer to destination string
473 * Use: Emits the key's full tag, which has the form
474 * `ID:TYPE[:TAG]'. This is used in the textual file format,
475 * and to identify passphrases for locked keys.
478 extern void key_fulltag(key */
*k*/
, dstr */
*d*/
);
480 /* --- @key_qtag@ --- *
482 * Arguments: @key_file *f@ = key file to find a key from
483 * @const char *tag@ = pointer to tag string
484 * @dstr *d@ = pointer to string for full tag name
485 * @key **k@ = where to store the key pointer
486 * @key_data ***kd@ = where to store the key data pointer
488 * Returns: Zero if OK, nonzero if it failed.
490 * Use: Performs a full lookup on a qualified tag name. The tag is
491 * qualified by the names of subkeys, separated by dots. Hence,
492 * a qualified tag is ID|TAG[.TAG...]. The various result
493 * pointers can be null to indicate that the result isn't
497 extern int key_qtag(key_file */
*f*/
, const char */
*tag*/
,
498 dstr */
*d*/
, key
**/
*k*/
, key_data
***/
*kd*/
);
500 /* --- @key_getattr@ --- *
502 * Arguments: @key_file *f@ = pointer to file
503 * @key *k@ = pointer to key
504 * @const char *n@ = pointer to attribute name
506 * Returns: Pointer to attribute value, or null if not found.
508 * Use: Returns the value of a key attribute.
511 extern const char *key_getattr(key_file */
*f*/
, key */
*k*/
,
514 /* --- @key_putattr@ --- *
516 * Arguments: @key_file *f@ = pointer to file
517 * @key *k@ = pointer to key
518 * @const char *n@ = pointer to attribute name
519 * @const char *v@ = pointer to attribute value or null
521 * Returns: Error code (one of the @KERR@ constants).
523 * Use: Inserts an attribute on a key. If an attribute with the same
524 * name already exists, it is deleted. Setting a null value
525 * removes the attribute.
528 extern int key_putattr(key_file */
*f*/
, key */
*k*/
,
529 const char */
*n*/
, const char */
*v*/
);
531 /* --- @key_mkattriter@ --- *
533 * Arguments: @key_attriter *i@ = pointer to attribute iterator
534 * @key *k@ = pointer to key
538 * Use: Initializes an attribute iterator. The attributes are
539 * returned by @key_nextattr@.
542 extern void key_mkattriter(key_attriter */
*i*/
, key */
*k*/
);
544 /* --- @key_nextattr@ --- *
546 * Arguments: @key_attriter *i@ = pointer to attribute iterator
547 * @const char **n, **v@ = pointers to name and value
549 * Returns: Zero if no attribute available, or nonzero if returned OK.
551 * Use: Returns the next attribute.
554 extern int key_nextattr(key_attriter */
*i*/
,
555 const char **/
*n*/
, const char **/
*v*/
);
557 /*----- Searching and iterating -------------------------------------------*/
559 /* --- @key_bytype@ --- *
561 * Arguments: @key_file *f@ = key file we want a key from
562 * @const char *type@ = type string for desired key
564 * Returns: Pointer to the best key to use, or null.
566 * Use: Looks up a key by its type. Returns the key with the latest
567 * expiry time. This function will not return an expired key.
570 extern key
*key_bytype(key_file */
*f*/
, const char */
*type*/
);
572 /* --- @key_byid@ --- *
574 * Arguments: @key_file *f@ = key file to find a key from
575 * @uint32 id@ = id to look for
577 * Returns: Key with matching id.
579 * Use: Returns a key given its id. This function will return an
580 * expired key, but not a deleted one.
583 extern key
*key_byid(key_file */
*f*/
, uint32
/*id*/);
585 /* --- @key_bytag@ --- *
587 * Arguments: @key_file *f@ = key file to find a key from
588 * @const char *tag@ = pointer to tag string
590 * Returns: Key with matching id or tag.
592 * Use: Returns a key given its tag or id. This function will return
593 * an expired key, but not a deleted one.
596 extern key
*key_bytag(key_file */
*f*/
, const char */
*tag*/
);
598 /* --- @key_mkiter@ --- *
600 * Arguments: @key_iter *i@ = pointer to iterator object
601 * @key_file *f@ = pointer to file structure
605 * Use: Initializes a key iterator. The keys are returned by
609 extern void key_mkiter(key_iter */
*i*/
, key_file */
*f*/
);
611 /* --- @key_next@ --- *
613 * Arguments: @key_iter *i@ = pointer to iterator object
615 * Returns: Pointer to next key, or null.
617 * Use: Returns the next key in some arbitrary sequence.
620 extern key
*key_next(key_iter */
*i*/
);
622 /*----- Fetching key data conveniently ------------------------------------*/
624 /* --- @key_fetchinit@ --- *
626 * Arguments: @const key_fetchdef *kf@ = pointer to base definition
627 * @key_packstruct *kps@ = pointer to destination packing def
628 * @void *p@ = pointer to destination block
630 * Returns: Pointer to packing definition.
632 * Use: Initializes a packing definition (@key_packdef@ structure).
633 * If @kps@ is null on entry, an appropriately sized block is
634 * allocated automatically. Otherwise it must be large enough.
637 extern key_packdef
*key_fetchinit(const key_fetchdef */
*kf*/
,
638 key_packstruct */
*kp*/
, void */
*p*/
);
640 /* --- @key_fetch@ --- *
642 * Arguments: @key_packdef *kp@ = pointer to packing structure
643 * @key *k@ = key file containing desired key
645 * Returns: Error code, or zero.
647 * Use: Fetches an unpacked key from a packed one.
650 extern int key_fetch(key_packdef */
*kp*/
, key */
*k*/
);
652 /* --- @key_fetchbyname@ --- *
654 * Arguments: @key_packdef *kp@ = pointer to packing structure
655 * @key_file *kf@ = key file containing desired key
656 * @const char *tag@ = user's tag describing the key
658 * Returns: Error code, or zero.
660 * Use: Fetches a named key from a key file and unpacks it
664 extern int key_fetchbyname(key_packdef */
*kp*/
,
665 key_file */
*kf*/
, const char */
*tag*/
);
667 /* --- @key_fetchdone@ --- *
669 * Arguments: @key_packdef *kp@ = pointer to packing structure
673 * Use: Frees a packing structure. If the structure was allocated by
674 * @key_fetchinit@ then it is freed.
677 extern void key_fetchdone(key_packdef */
*kp*/
);
679 /*----- Other functions ---------------------------------------------------*/
681 /* --- @key_moan@ --- *
683 * Arguments: @const char *file@ = name of the file
684 * @int line@ = line number in file
685 * @const char *msg@ = error message
686 * @void *p@ = argument pointer
690 * Use: Reports an error message about loading a key file.
693 extern void key_moan(const char */
*file*/
, int /*line*/,
694 const char */
*msg*/
, void */
*p*/
);
696 /*----- That's all, folks -------------------------------------------------*/