3 * $Id: key.h,v 1.5 2000/02/12 18:55:40 mdw Exp $
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 /*----- Revision history --------------------------------------------------*
33 * Revision 1.5 2000/02/12 18:55:40 mdw
34 * Make it all compile properly.
36 * Revision 1.4 2000/02/12 18:21:02 mdw
37 * Overhaul of key management (again).
39 * Revision 1.3 1999/12/22 15:47:48 mdw
40 * Major key-management revision.
42 * Revision 1.2 1999/12/10 23:29:48 mdw
43 * Change header file guard names.
45 * Revision 1.1 1999/09/03 08:41:12 mdw
50 #ifndef CATACOMB_KEY_H
51 #define CATACOMB_KEY_H
57 /*----- Header files ------------------------------------------------------*/
62 #include <mLib/bits.h>
63 #include <mLib/dstr.h>
64 #include <mLib/hash.h>
67 #ifndef CATACOMB_KEY_DATA_H
68 # include "key-data.h"
75 /*----- Data structures ---------------------------------------------------*/
77 /* --- Key attributes --- *
79 * Each attribute is stored as a symbol in a symbol table. The value is
80 * the plain (not url-encoded) text to be written to the the file. If the
81 * value is binary data, then by this point it's base-64 encoded.
84 typedef struct key_attr
{
85 sym_base _b
; /* Symbol table data */
86 char *p
; /* Pointer to attribute value */
89 /* --- Main key structure --- *
91 * Each key is stored in two symbol tables, one indexed by keyid, and the
92 * other indexed by type. Because many keys can have the same type, the type
93 * table contains a list of keys, sorted in descending order of expiry.
98 /* --- Hashtable management --- */
100 hash_base _b
; /* Symbol table data */
101 struct key
*next
; /* Next key of the same type */
103 /* --- Basic key attributes --- */
105 uint32 id
; /* Key id used to name it */
106 char *tag
; /* Textual tag name */
107 char *type
; /* Textual key type */
108 time_t exp
, del
; /* Expiry times for keys */
110 /* --- The key data itself --- */
112 key_data k
; /* The actual key data */
114 /* --- Other attributes and commentary --- */
116 sym_table a
; /* Hashtable of key attributes */
117 char *c
; /* Any additional comments */
120 /* --- The keys-by-type entries --- */
122 typedef struct key_ref
{
123 sym_base _b
; /* Symbol table data */
124 key
*k
; /* Pointer to first key in list */
127 /* --- A key file --- */
129 typedef struct key_file
{
130 FILE *fp
; /* File pointer open on file */
131 char *name
; /* Filename used to create it */
132 unsigned f
; /* Various useful flags */
133 hash_table byid
; /* Table of keys by keyid */
134 sym_table bytype
; /* Table of keys by type */
135 sym_table bytag
; /* Table of keys by tag */
136 size_t idload
; /* Loading on id table */
139 /* --- Key file flags --- */
142 KF_WRITE
= 1, /* File opened for writing */
143 KF_MODIFIED
= 2 /* File has been modified */
146 /* --- Iterating over keys --- *
148 * Both of these are simple symbol table iterators, but they're made distinct
149 * types for the dubious benefits that type safety brings.
152 typedef struct { hash_iter i
; time_t t
; } key_iter
;
153 typedef struct { sym_iter i
; } key_attriter
;
155 /* --- File opening options --- */
162 /* --- Various other magic numbers --- */
164 #define KEXP_FOREVER ((time_t)-1) /* Never expire this key */
165 #define KEXP_EXPIRE ((time_t)-2) /* Expire this key when unused */
167 /* --- Key error codes --- */
170 KERR_OK
= 0, /* No error */
171 KERR_BADTAG
= -1, /* Malformed tag string */
172 KERR_BADTYPE
= -2, /* Malformed type string */
173 KERR_BADCOMMENT
= -3, /* Malformed comment string */
174 KERR_DUPID
= -4, /* Duplicate keyid */
175 KERR_DUPTAG
= -5, /* Duplicate key tag string */
176 KERR_READONLY
= -6, /* Key file is read-only */
177 KERR_WILLEXPIRE
= -7, /* Key will eventually expire */
178 KERR_EXPIRED
= -8, /* Key has already expired */
179 KERR_BADFLAGS
= -9, /* Error in flags string */
180 KERR_BADPASS
= -10, /* Error decrypting locked key */
181 KERR_WRONGTYPE
= -11, /* Key has incorrect type */
182 KERR_NOTFOUND
= -12, /* Key couldn't be found */
183 KERR_MAX
/* Largest possible error */
186 /* --- Write error codes --- */
189 KWRITE_OK
, /* Everything went fine */
190 KWRITE_FAIL
= -1, /* Close attempt failed */
191 KWRITE_BROKEN
= -2 /* Key ring needs manual fixing */
194 /* --- Error reporting functions for @key_merge@ and @key_open@ --- */
196 typedef void key_reporter(const char */
*file*/
, int /*line*/,
197 const char */
*err*/
, void */
*p*/
);
199 /* --- Macros for testing expiry --- */
201 #define KEY_EXPIRED(now, exp) \
202 ((exp) == KEXP_EXPIRE || ((exp) != KEXP_FOREVER && (exp) < (now)))
204 /*----- Reading and writing keys and files --------------------------------*/
206 /* --- @key_merge@ --- *
208 * Arguments: @key_file *f@ = pointer to file structure
209 * @const char *file@ = name of file (for error messages)
210 * @FILE *fp@ = file handle to read from
211 * @key_reporter *rep@ = error reporting function
212 * @void *arg@ = argument for function
214 * Returns: Error code (one of the @KERR@ constants).
216 * Use: Reads keys from a file, and inserts them into the file.
219 extern int key_merge(key_file */
*f*/
, const char */
*file*/
, FILE */
*fp*/
,
220 key_reporter */
*rep*/
, void */
*arg*/
);
222 /* --- @key_extract@ --- *
224 * Arguments: @key_file *f@ = pointer to file structure
225 * @key *k@ = key to extract
226 * @FILE *fp@ = file to write on
227 * @const key_filter *kf@ = pointer to key selection block
229 * Returns: Zero if OK, EOF on error.
231 * Use: Extracts a key to an ouptut file.
234 extern int key_extract(key_file */
*f*/
, key */
*k*/
, FILE */
*fp*/
,
235 const key_filter */
*kf*/
);
237 /* --- @key_open@ --- *
239 * Arguments: @key_file *f@ = pointer to file structure to initialize
240 * @const char *file@ = pointer to the file name
241 * @int how@ = opening options (@KOPEN_*@).
242 * @key_reporter *rep@ = error reporting function
243 * @void *arg@ = argument for function
245 * Returns: Zero if it worked, nonzero otherwise.
247 * Use: Opens a key file, reads its contents, and stores them in a
248 * structure. The file is locked appropriately until closed
249 * using @key_close@. On an error, everything is cleared away
250 * tidily. If the file is opened with @KOPEN_WRITE@, it's
251 * created if necessary, with read and write permissions for its
255 extern int key_open(key_file */
*f*/
, const char */
*file*/
, int /*how*/,
256 key_reporter */
*rep*/
, void */
*arg*/
);
258 /* --- @key_close@ --- *
260 * Arguments: @key_file *f@ = pointer to key file block
262 * Returns: A @KWRITE_@ code indicating how it went.
264 * Use: Frees all the key data, writes any changes. Make sure that
265 * all hell breaks loose if this returns @KWRITE_BROKEN@.
268 extern int key_close(key_file */
*f*/
);
270 /* --- @key_save@ --- *
272 * Arguments: @key_file *f@ = pointer to key file block
274 * Returns: A @KWRITE_@ code indicating how well it worked.
276 * Use: Writes a key file's data back to the actual file. This code
277 * is extremely careful about error handling. It should usually
278 * be able to back out somewhere sensible, but it can tell when
279 * it's got itself into a real pickle and starts leaving well
282 * Callers, please make sure that you ring alarm bells when this
283 * function returns @KWRITE_BROKEN@.
286 extern int key_save(key_file */
*f*/
);
288 /* --- @key_lockfile@ --- *
290 * Arguments: @key_file *f@ = pointer to file structure to initialize
291 * @const char *file@ = pointer to the file name
292 * @int how@ = opening options (@KOPEN_*@).
294 * Returns: Zero if it worked, nonzero otherwise.
296 * Use: Opens a keyfile and stores the information needed for
297 * continued access in the structure.
299 * If the file is opened with @KOPEN_WRITE@, it's created if
300 * necessary with read and write permissions for owner only, and
301 * locked for update while it's open.
303 * This is a system-dependent routine, and only really intended
304 * for the private use of @key_open@.
307 extern int key_lockfile(key_file */
*f*/
, const char */
*file*/
, int /*how*/);
309 /*----- Creating and manipulating keys ------------------------------------*/
313 * Arguments: @key_file *f@ = pointer to key file
314 * @uint32 id@ = keyid to set
315 * @const char *type@ = the type of this key
316 * @time_t exp@ = when the key expires
317 * @int *err@ = where to store the error condition
319 * Returns: Key block containing new data, or null if it couldn't be
322 * Use: Attaches a new key to a key file. You must have a writable
323 * key file for this to work.
325 * The type is a key type string. This interface doesn't care
326 * about how type strings are formatted: it just treats them as
327 * opaque gobs of text. Clients are advised to choose some
328 * standard for representing key types, though.
330 * The expiry time should either be a time in the future, or the
331 * magic value @KEXP_FOREVER@ which means `never expire this
332 * key'. Be careful with `forever' keys. If I were you, I'd
333 * use a more sophisticated key management system than this for
336 * You have to set the actual key yourself.
339 extern key
*key_new(key_file */
*f*/
, uint32
/*id*/, const char */
*type*/
,
340 time_t /*exp*/, int */
*err*/
);
342 /* --- @key_delete@ --- *
344 * Arguments: @key_file *f@ = pointer to file block
345 * @key *k@ = key to delete
347 * Returns: Error code (one of the @KERR@ constants).
349 * Use: Removes the given key from the list. The key file must be
350 * writable. (Due to the horridness of the data structures,
351 * deleted keys aren't actually removed, just marked so that
352 * they can't be looked up or iterated over. One upshot of
353 * this is that they don't get written back to the file when
357 extern int key_delete(key_file */
*f*/
, key */
*k*/
);
359 /* --- @key_expire@ --- *
361 * Arguments: @key_file *f@ = pointer to file block
362 * @key *k@ = pointer to key block
364 * Returns: Error code (one of the @KERR@ constants).
366 * Use: Immediately marks the key as expired. It may be removed
367 * immediately, if it is no longer required, and will be removed
368 * by a tidy operation when it is no longer required. The key
369 * file must be writable.
372 extern int key_expire(key_file */
*f*/
, key */
*k*/
);
374 /* --- @key_used@ --- *
376 * Arguments: @key_file *f@ = pointer to key file
377 * @key *k@ = pointer to key block
378 * @time_t t@ = when key can be removed
380 * Returns: Zero if OK, nonzero on failure.
382 * Use: Marks a key as being required until a given time. Even
383 * though the key may expire before then (and won't be returned
384 * by type after that time), it will still be available when
385 * requested explicitly by id. The key file must be writable.
387 * The only (current) reason for failure is attempting to use
388 * a key which can expire for something which can't.
391 extern int key_used(key_file */
*f*/
, key */
*k*/
, time_t /*t*/);
393 /*----- Setting and reading attributes ------------------------------------*/
395 /* --- @key_chkident@ --- *
397 * Arguments: @const char *p@ = pointer to a type string
399 * Returns: Zero if OK, -1 on error.
401 * Use: Checks whether an identification component string is OK.
404 extern int key_chkident(const char */
*p*/
);
406 /* --- @key_chkcomment@ --- *
408 * Arguments: @const char *p@ = pointer to a comment string
410 * Returns: Zero if OK, -1 on error.
412 * Use: Checks whether a comment string is OK.
415 extern int key_chkcomment(const char */
*p*/
);
417 /* --- @key_setcomment@ --- *
419 * Arguments: @key_file *f@ = pointer to key file block
420 * @key *k@ = pointer to key block
421 * @const char *c@ = pointer to comment to set, or zero
423 * Returns: Error code (one of the @KERR@ constants).
425 * Use: Replaces the key's current comment with a new one.
428 extern int key_setcomment(key_file */
*f*/
, key */
*k*/
, const char */
*c*/
);
430 /* --- @key_settag@ --- *
432 * Arguments: @key_file *f@ = pointer to key file block
433 * @key *k@ = pointer to key block
434 * @const char *tag@ = pointer to comment to set, or zero
436 * Returns: Error code (one of the @KERR@ constants).
438 * Use: Replaces the key's current tag with a new one.
441 extern int key_settag(key_file */
*f*/
, key */
*k*/
, const char */
*tag*/
);
443 /* --- @key_fulltag@ --- *
445 * Arguments: @key *k@ = pointer to key
446 * @dstr *d@ = pointer to destination string
450 * Use: Emits the key's full tag, which has the form
451 * `ID:TYPE[:TAG]'. This is used in the textual file format,
452 * and to identify passphrases for locked keys.
455 extern void key_fulltag(key */
*k*/
, dstr */
*d*/
);
457 /* --- @key_qtag@ --- *
459 * Arguments: @key_file *f@ = key file to find a key from
460 * @const char *tag@ = pointer to tag string
461 * @dstr *d@ = pointer to string for full tag name
462 * @key **k@ = where to store the key pointer
463 * @key_data **kd@ = where to store the key data pointer
465 * Returns: Zero if OK, nonzero if it failed.
467 * Use: Performs a full lookup on a qualified tag name. The tag is
468 * qualified by the names of subkeys, separated by dots. Hence,
469 * a qualified tag is ID|TAG[.TAG...]. The various result
470 * pointers can be null to indicate that the result isn't
474 extern int key_qtag(key_file */
*f*/
, const char */
*tag*/
,
475 dstr */
*d*/
, key
**/
*k*/
, key_data
**/
*kd*/
);
477 /* --- @key_getattr@ --- *
479 * Arguments: @key_file *f@ = pointer to file
480 * @key *k@ = pointer to key
481 * @const char *n@ = pointer to attribute name
483 * Returns: Pointer to attribute value, or null if not found.
485 * Use: Returns the value of a key attribute.
488 extern const char *key_getattr(key_file */
*f*/
, key */
*k*/
,
491 /* --- @key_putattr@ --- *
493 * Arguments: @key_file *f@ = pointer to file
494 * @key *k@ = pointer to key
495 * @const char *n@ = pointer to attribute name
496 * @const char *v@ = pointer to attribute value or null
498 * Returns: Error code (one of the @KERR@ constants).
500 * Use: Inserts an attribute on a key. If an attribute with the same
501 * name already exists, it is deleted. Setting a null value
502 * removes the attribute.
505 extern int key_putattr(key_file */
*f*/
, key */
*k*/
,
506 const char */
*n*/
, const char */
*v*/
);
508 /* --- @key_mkattriter@ --- *
510 * Arguments: @key_attriter *i@ = pointer to attribute iterator
511 * @key *k@ = pointer to key
515 * Use: Initializes an attribute iterator. The attributes are
516 * returned by @key_nextattr@.
519 extern void key_mkattriter(key_attriter */
*i*/
, key */
*k*/
);
521 /* --- @key_nextattr@ --- *
523 * Arguments: @key_attriter *i@ = pointer to attribute iterator
524 * @const char **n, **v@ = pointers to name and value
526 * Returns: Zero if no attribute available, or nonzero if returned OK.
528 * Use: Returns the next attribute.
531 extern int key_nextattr(key_attriter */
*i*/
,
532 const char **/
*n*/
, const char **/
*v*/
);
534 /*----- Searching and iterating -------------------------------------------*/
536 /* --- @key_bytype@ --- *
538 * Arguments: @key_file *f@ = key file we want a key from
539 * @const char *type@ = type string for desired key
541 * Returns: Pointer to the best key to use, or null.
543 * Use: Looks up a key by its type. Returns the key with the latest
544 * expiry time. This function will not return an expired key.
547 extern key
*key_bytype(key_file */
*f*/
, const char */
*type*/
);
549 /* --- @key_byid@ --- *
551 * Arguments: @key_file *f@ = key file to find a key from
552 * @uint32 id@ = id to look for
554 * Returns: Key with matching id.
556 * Use: Returns a key given its id. This function will return an
557 * expired key, but not a deleted one.
560 extern key
*key_byid(key_file */
*f*/
, uint32
/*id*/);
562 /* --- @key_bytag@ --- *
564 * Arguments: @key_file *f@ = key file to find a key from
565 * @const char *tag@ = pointer to tag string
567 * Returns: Key with matching id or tag.
569 * Use: Returns a key given its tag or id. This function will return
570 * an expired key, but not a deleted one.
573 extern key
*key_bytag(key_file */
*f*/
, const char */
*tag*/
);
575 /* --- @key_mkiter@ --- *
577 * Arguments: @key_iter *i@ = pointer to iterator object
578 * @key_file *f@ = pointer to file structure
582 * Use: Initializes a key iterator. The keys are returned by
586 extern void key_mkiter(key_iter */
*i*/
, key_file */
*f*/
);
588 /* --- @key_next@ --- *
590 * Arguments: @key_iter *i@ = pointer to iterator object
592 * Returns: Pointer to next key, or null.
594 * Use: Returns the next key in some arbitrary sequence.
597 extern key
*key_next(key_iter */
*i*/
);
599 /*----- Other functions ---------------------------------------------------*/
601 /* --- @key_moan@ --- *
603 * Arguments: @const char *file@ = name of the file
604 * @int line@ = line number in file
605 * @const char *msg@ = error message
606 * @void *p@ = argument pointer
610 * Use: Reports an error message about loading a key file.
613 extern void key_moan(const char */
*file*/
, int /*line*/,
614 const char */
*msg*/
, void */
*p*/
);
616 /* --- @key_strerror@ --- *
618 * Arguments: @int err@ = error code from @key_new@
620 * Returns: Pointer to error string.
622 * Use: Translates a @KERR@ error code into a human-readable string.
625 extern const char *key_strerror(int /*err*/);
627 /*----- That's all, folks -------------------------------------------------*/