d03ab969 |
1 | .\" -*-nroff-*- |
052b36d0 |
2 | .ie t \{\ |
8404fd75 |
3 | . if \n(.g \{\ |
4 | . fam P |
5 | . \} |
052b36d0 |
6 | . ds ss \s8\u |
7 | . ds se \d\s0 |
1476eebc |
8 | . ds us \s8\d |
9 | . ds ue \u\s0 |
8404fd75 |
10 | . ds *b \(*b |
052b36d0 |
11 | .\} |
12 | .el \{\ |
13 | . ds ss ^ |
14 | . ds se |
1476eebc |
15 | . ds us _ |
8404fd75 |
16 | . ds ue |
17 | . ds *b \fIbeta\fP |
052b36d0 |
18 | .\} |
c65df279 |
19 | .de VS |
20 | .sp 1 |
21 | .RS |
22 | .nf |
23 | .ft B |
24 | .. |
25 | .de VE |
26 | .ft R |
27 | .fi |
28 | .RE |
29 | .sp 1 |
30 | .. |
d07dfe80 |
31 | .TH key 1 "5 June 1999" "Straylight/Edgeware" "Catacomb cryptographic library" |
d03ab969 |
32 | .SH NAME |
33 | key \- simple key management system |
34 | .SH SYNOPSIS |
35 | .B key |
36 | .RB [ \-k |
37 | .IR keyring ] |
38 | .I command |
39 | .PP |
40 | where |
41 | .I command |
42 | is one of: |
43 | .PP |
c65df279 |
44 | .B help |
45 | .RI [ command ...] |
46 | .br |
47 | .B show |
48 | .RI [ item ...] |
49 | .br |
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50 | .B add |
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51 | .RB [ \-lqrLS ] |
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52 | .RB [ \-a |
53 | .IR alg ] |
54 | .RB [ \-b | \-B |
d03ab969 |
55 | .IR bits ] |
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56 | .RB [ \-p |
57 | .IR param ] |
d07dfe80 |
58 | .RB [ \-R |
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59 | .IR tag ] |
60 | .br |
61 | \h'8n' |
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62 | .RB [ \-A |
63 | .IR seed-alg ] |
64 | .RB [ \-s |
65 | .IR seed ] |
66 | .RB [ \-n |
67 | .IR bits ] |
68 | .br |
69 | \h'8n' |
d03ab969 |
70 | .RB [ \-e |
71 | .IR expire ] |
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72 | .RB [ \-t |
73 | .IR tag ] |
d03ab969 |
74 | .RB [ \-c |
75 | .IR comment ] |
eb31b00e |
76 | .RB [ \-C |
77 | .IR curve ] |
78 | .br |
79 | \h'8n' |
d03ab969 |
80 | .I type |
81 | .IR attr ... |
82 | .br |
83 | .B expire |
052b36d0 |
84 | .IR tag ... |
d03ab969 |
85 | .br |
86 | .B delete |
052b36d0 |
87 | .IR tag ... |
88 | .br |
89 | .B tag |
90 | .I tag |
91 | .RI [ new-tag ] |
92 | .br |
93 | .B comment |
94 | .I tag |
95 | .RI [ comment ] |
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96 | .br |
97 | .B setattr |
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98 | .I tag |
d03ab969 |
99 | .IR attr ... |
100 | .br |
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101 | .B lock |
102 | .I qtag |
103 | .br |
104 | .B unlock |
105 | .I qtag |
106 | .br |
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107 | .B list |
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108 | .RB [ \-uqv ] |
109 | .RB [ \-f |
110 | .IR filter ] |
111 | .RI [ tag ...] |
112 | .br |
113 | .B fingerprint |
114 | .RB [ \-f |
115 | .IR filter ] |
b817bfc6 |
116 | .RB [ \-a |
117 | .IR hash ] |
052b36d0 |
118 | .RI [ tag ...] |
d03ab969 |
119 | .br |
120 | .B tidy |
121 | .br |
122 | .B extract |
052b36d0 |
123 | .RB [ \-f |
124 | .IR filter ] |
d03ab969 |
125 | .I file |
052b36d0 |
126 | .RI [ tag ...] |
d03ab969 |
127 | .br |
128 | .B merge |
129 | .I file |
130 | .SH DESCRIPTION |
131 | The |
132 | .B key |
133 | command performs useful operations on Catacomb keyring files. It |
134 | provides a number of subcommands, by which the various operations may be |
135 | carried out. |
136 | .SS "Global options" |
137 | Before the command name, |
138 | .I "global options" |
139 | may be given. The following global options are supported: |
140 | .TP |
c65df279 |
141 | .BR "\-h, \-\-help " [ \fIcommand ...] |
d03ab969 |
142 | Writes a brief summary of |
143 | .BR key 's |
144 | various options to standard output, and |
c65df279 |
145 | returns a successful exit status. With command names, gives help on |
146 | those commands. |
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147 | .TP |
148 | .B "\-v, \-\-version" |
149 | Writes the program's version number to standard output, and returns a |
150 | successful exit status. |
151 | .TP |
152 | .B "\-u, \-\-usage" |
153 | Writes a very terse command line summary to standard output, and returns |
154 | a successful exit status. |
155 | .TP |
c9e31e42 |
156 | .BI "\-k, \-\-keyring " file |
d03ab969 |
157 | Names the keyring file which |
158 | .B key |
159 | is to process. The default keyring, used if this option doesn't specify |
160 | one, is the file named |
161 | .B keyring |
162 | in the current directory. The keyring must be stored in a regular file: |
163 | pipes, sockets, devices etc. are not allowed. |
164 | The |
165 | .B key |
166 | program attempts to lock the keyring before accessing it, using |
167 | .BR fcntl (2) |
168 | locking. It will however time out after a short while (10 seconds) and |
169 | report a failure. |
170 | .SS Concepts |
171 | In addition to the actual key data itself, a Catacomb key has a number |
172 | of other pieces of information attached to it: |
173 | .TP |
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174 | .B "keyid" |
175 | Every key has a 32-bit identifying number, written in hexadecimal. |
176 | Keyids are not actually related to the key contents: they're generated |
177 | randomly. Applications use keyids to refer to specific keys; users are |
178 | probably better off with tags and types. A |
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179 | .I deleted |
180 | key cannot be looked up by keyid. |
181 | .TP |
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182 | .B "tag" |
183 | A key's tag is a unique string which can be used by users and |
184 | applications to identify the key. Tag strings may not contain spaces, |
185 | colons or dots. A |
186 | .I deleted |
187 | key cannot be looked up by tag. Whenever a tag name is wanted, a hex |
188 | keyid or key type string can be given instead. |
189 | .TP |
190 | .B "type" |
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191 | A key's type string describes what the key may be used for. The type |
192 | string is arbitrary, except that it may not contain whitespace |
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193 | characters, dots or colons. Applications use key types to obtain an |
194 | arbitrary but suitable key for some purpose. An |
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195 | .I expired |
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196 | key cannot be looked up by type, but may be looked up by keyid or tag. |
197 | .TP |
198 | .B "key encoding" |
199 | There are a number of different ways in which keys can be represented, |
200 | according to the uses to which the key will be put. Most symmetric |
201 | algorithms use |
202 | .I binary |
203 | keys. Keys used with number-theoretic systems (like most common |
204 | public-key systems) use |
205 | .I "multiprecision integer" |
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206 | keys. Elliptic curve systems use |
207 | .I "curve point" |
208 | keys, which are either a pair of integers representing field elements, |
209 | or a `point at infinity'. Algorithms which require several key |
210 | constituents (again, like most public-key systems) use |
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211 | .I structured |
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212 | keys, which consist of a collection of named parts. It's possible to |
213 | store an |
214 | .I "ASCII string" |
215 | as a key, though this is usually done as a component of a structured |
216 | key. Finally, keys (including structured keys) can be encrypted. |
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217 | .TP |
218 | .B "filter" |
219 | Keys and key components may be selected by a filter expression, a |
220 | sequence of flag names separated by commas. Flags are: |
221 | .BR binary , |
222 | .BR integer , |
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223 | .BR struct , |
224 | .BR ec , |
225 | .BR string , |
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226 | or |
227 | .B encrypt |
228 | (describing the key encoding); |
229 | .BR symmetric , |
230 | .BR private , |
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231 | .BR public , |
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232 | or |
233 | .B shared |
234 | (describing the category of key); |
235 | .B burn |
236 | and its negation |
237 | .B \-burn |
238 | (whether the key should be erased from memory after use); and |
239 | .B secret |
240 | and its negation |
241 | .B \-secret |
242 | (whether the key is safe to divulge). |
243 | .TP |
244 | .B "qualified tag" |
245 | A key component may be identified by the key's tag (or keyid, or type). |
246 | Subcomponents of structured keys are identified by following the tag by |
247 | a dot and the name of the subcomponent. |
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248 | .TP |
249 | .B "expiry time" |
250 | Most keys expire after a certain amount of time. Once a key has |
251 | expired, it will no longer be chosen as a result of a lookup by key |
252 | type. However, it is not deleted until its deletion time is also |
253 | reached. |
254 | .TP |
255 | .B "deletion time" |
256 | A key's deletion time is the latest expiry time of any of the objects |
257 | which require that key. For example, a key used for authenticating |
258 | cryptographic cookies should have its deletion time set to the longest |
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259 | expiry time of any of the cookies it can authenticate. Once a key's |
260 | deletion time is passed, it can no longer be referred to by |
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261 | applications, and will be removed from the keyring next time it's |
262 | written to disk. |
263 | .TP |
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264 | .B "comment" |
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265 | A key may be given a comment when it's created. The comment is for the |
266 | benefit of users, and isn't interpreted by applications at all. |
267 | (Hopefully.) |
268 | .TP |
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269 | .B "attributes" |
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270 | A key as zero or more name/value pairs. The names and values are |
271 | arbitrary strings, except they may not contain null bytes. Some |
272 | attributes may have meaning for particular applications or key types; |
273 | others may be assigned global meanings in future. |
274 | .SH "COMMAND REFERENCE" |
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275 | .SS help |
276 | The |
277 | .B help |
278 | command behaves exactly as the |
279 | .B \-\-help |
280 | option. With no arguments, it shows an overview of |
281 | .BR key 's |
282 | options; with arguments, it describes the named subcommands. |
283 | .SS show |
284 | The |
285 | .B show |
286 | command prints various lists of tokens understood by |
287 | .BR key . |
288 | With no arguments, it prints all of the lists; with arguments, it prints |
289 | just the named lists, in order. The recognized lists can be enumerated |
290 | using the |
291 | .VS |
292 | key show list |
293 | .VE |
294 | command. The lists are as follows. |
295 | .TP |
296 | .B list |
297 | The lists which can be enumerated by the |
298 | .B show |
299 | command. |
300 | .TP |
301 | .B hash |
302 | The hash functions which can be used with the |
303 | .B fingerprint |
304 | command. |
305 | .TP |
306 | .B ec |
307 | The built-in elliptic curves which can be used with the |
308 | .B add \-a ec |
309 | command. |
310 | .TP |
311 | .B dh |
312 | The built-in Diffie-Hellman groups which can be used with the |
313 | .B add \-a dh |
314 | command. |
315 | .TP |
316 | .B keygen |
317 | The key-generation algorithms which are acceptable to the |
318 | .B \-a |
319 | option of the |
320 | .B add |
321 | command. |
322 | .TP |
323 | .B seed |
324 | The pseudorandom generators which are acceptable to the |
325 | .B \-s |
326 | option of the |
327 | .B add |
328 | command. |
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329 | .SS add |
330 | The |
331 | .B add |
332 | command creates a new key and adds it to the keyring. The command |
333 | accepts the following options: |
334 | .TP |
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335 | .BI "\-a, \-\-algorithm " alg |
336 | Selects a key generation algorithm. The default algorithm is |
337 | .BR binary ; |
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338 | the different algorithms are described below. The command |
339 | .B key show keygen |
340 | lists the recognized key-generation algorithms. |
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341 | .TP |
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342 | .BI "\-b, \-\-bits " bits |
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343 | The length of the key to generate, in bits. The default, if this option |
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344 | is not supplied, depends on the key-generation algorithm. |
345 | .TP |
346 | .BI "\-B, \-\-qbits " bits |
347 | The length of the subsidiary key or parameter, in bits. Not all |
348 | key-generation algorithms have a subsidiary key size. |
349 | .TP |
350 | .BI "\-p, \-\-parameters " tag |
351 | Selects a key containing parameter values to copy. Not all |
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352 | key-generation algorithms allow the use of shared parameters. A new key |
353 | also inherits attributes from its parameter key. |
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354 | .TP |
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355 | .BI "\-A, \-\-seedalg " seed-alg |
356 | Use the deterministic random number generator algorithm |
357 | .I seed-alg |
358 | to generate the key. Use |
359 | .I before |
360 | the |
361 | .B \-s |
362 | or |
363 | .B \-n |
364 | options; without one of these, |
365 | .B \-A |
366 | has no effect. The default algorithm is |
367 | .BR rmd160-mgf . |
368 | The command |
369 | .B key show seed |
370 | shows a list of recognized seeding algorithms. The seeding algorithm |
371 | used to generate a key is recorded as the key's |
372 | .B seedalg |
373 | attribute. |
374 | .TP |
375 | .BI "\-s, \-\-seed " seed |
376 | Generate the key deterministically using the given |
377 | .IR seed , |
378 | which should be a Base64-encoded binary string. This is mainly useful |
379 | for parameters keys (types |
380 | .BR dsa-param |
381 | and |
382 | .BR dh-param ), |
383 | to demonstrate that a set of parameters has been generated in an honest |
384 | fashion. The |
385 | .B dsarand |
386 | generation algorithm can be used to generate |
387 | .B dsa-param |
388 | keys as required by FIPS186. The requested seed is recorded, |
389 | Base64-encoded, as the new key's |
390 | .B seed |
391 | attribute. |
392 | .TP |
393 | .BI "\-n, \-\-newseed " bits |
394 | Generate a new seed, with the given length in |
395 | .IR bits . |
396 | The generated seed is recorded, Base64-encoded, as the new key's |
397 | .B seed |
398 | attribute. |
399 | .TP |
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400 | .BI "\-e, \-\-expire " expire |
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401 | The expiry date for the generated key. This may be the string |
402 | .RB ` forever ' |
403 | if the key should never expire automatically, or any date acceptable to |
404 | the |
405 | .BR getdate (3) |
406 | library function. Briefly, |
407 | .B getdate |
408 | understands absolute dates such as |
409 | .RB ` 1999-08-02 ' |
410 | or |
411 | .RB ` "August 2nd, 1999" ', |
412 | and (perhaps more usefully) relative dates such as |
413 | .RB ` "+2 weeks" '. |
414 | The default is to allow a 2 week expiry, which isn't useful. |
415 | .TP |
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416 | .BI "\-c, \-\-comment " comment |
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417 | Sets a comment for the key. The default is not to attach a comment. |
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418 | .TP |
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419 | .BI "\-C, \-\-curve " curve-spec |
420 | Use the elliptic curve described by |
421 | .I curve-spec |
422 | when generating elliptic curve parameters. |
423 | .TP |
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424 | .BI "\-t, \-\-tag " tag |
425 | Selects a tag string for the key. The default is not to set a tag. It |
426 | is an error to select a tag which already exists. |
427 | .TP |
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428 | .BI "\-r, \-\-retag" |
429 | If a |
430 | .B \-t |
431 | option is given, remove this tag from any key which already has it. |
432 | .TP |
433 | .BI "\-R, \-\-rand-id " tag |
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434 | Selects the key to use for the random number generator. Catacomb's |
435 | random number generator can be |
436 | .IR keyed , |
437 | so that, even if the inputs to the generator are compromised, knowledge |
438 | of the key is also necessary to be able to predict the output. By |
439 | default, the latest-expiring key with type |
440 | .B catacomb-rand |
441 | is used, if present; if not, no key is used. |
442 | .TP |
443 | .BI "\-l, \-\-lock" |
444 | Requests that the secret parts of the newly-generated key be encrypted |
445 | using a passphrase. |
446 | .TP |
447 | .BI "\-q, \-\-quiet" |
448 | Suppresses the progress indication which is usually generated while |
449 | time-consuming key generation tasks are being performed. |
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450 | .TP |
451 | .BI "\-L, --lim-lee" |
452 | When generating Diffie-Hellman parameters, generate a Lim-Lee prime |
453 | rather than a random (or safe) prime. See the details on Diffie-Hellman |
454 | key generation below. |
455 | .TP |
456 | .BI "\-S, --subgroup" |
457 | When generating Diffie-Hellman parameters with a Lim-Lee prime, choose a |
458 | generator of a prime-order subgroup rather than a subgroup of order |
459 | .RI ( p "- 1)/2." |
d03ab969 |
460 | .PP |
461 | The key's type is given by the required |
462 | .I type |
463 | argument. Following the type are zero or more attributes, which are |
464 | attached to the key in the same way as for the |
465 | .B setattr |
466 | command. |
467 | .PP |
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468 | The key-generation algorithms supported are as follows: |
469 | .TP |
470 | .B "binary" |
471 | Generates a plain binary key of the requested length. If the requested |
472 | key length is not a multiple of eight, the high-order bits of the first |
473 | octet of the key are zeroed. The default key length is 128 bits. |
474 | .TP |
475 | .B "des" |
476 | Generates a DES key, with parity bits. The key length must be 56, 112 |
477 | or 168; the default is 56. The low-order bit of each octet is ignored by |
478 | the DES algorithm; it is used to give each octet odd parity. |
479 | .TP |
480 | .B "rsa" |
481 | Generates a public/private key pair for use with the RSA algorithm. |
482 | .IP |
483 | The key components are |
484 | .I p |
485 | and |
486 | .IR q , |
487 | a pair of prime numbers; |
488 | .IR n , |
489 | the product of |
490 | .I p |
491 | and |
492 | .IR q ; |
493 | .IR e , |
494 | the public exponent; |
495 | .IR d , |
496 | the private exponent, chosen such that |
497 | .IR ed \ \(==\ 1 |
498 | (mod |
499 | .RI ( p \ \-\ 1)( q \ \-\ 1)); |
500 | and some other values useful for optimizing private-key operations: |
501 | .IR q \*(ss\-1\*(se\ mod\ p , |
502 | .IR d \ mod\ p \ \-\ 1, |
503 | and |
504 | .IR d \ mod\ q \ \-\ 1. |
505 | The values |
506 | .I n |
507 | and |
508 | .I e |
509 | constitute the public key; the rest must be kept secret. The key size |
510 | requested by the |
511 | .B \-b |
512 | option determines the size of the modulus |
513 | .IR n ; |
514 | the default is 1024 bits. |
515 | .IP |
516 | The key generation algorithm chooses |
517 | .I p |
518 | and |
519 | .I q |
520 | to be |
521 | .I strong |
522 | primes: both |
523 | .IR p \ \-\ 1 |
524 | and |
525 | .IR p \ +\ 1 |
526 | have large prime factors \- call them |
527 | .I r |
528 | and |
529 | .I s |
530 | respectively \- and |
531 | .IR r \ \-\ 1 |
532 | also has a large prime factor; |
533 | .I q |
534 | has similar properties. |
535 | .IP |
536 | The modulus |
537 | .I n |
538 | cannot be sensibly used as a shared parameter, since knowledge of |
539 | corrssponding public and private exponents is sufficient to be able to |
540 | factor the modulus and recover other users' private keys. |
541 | .TP |
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542 | .B "dh-param" |
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543 | Generates parameters for use with the Diffie-Hellman key exchange |
544 | protocol, and many related systems, such as ElGamal encryption and |
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545 | signatures, and even DSA. (The separate DSA algorithm uses the |
546 | generator described in FIPS186-1.) |
547 | .IP |
548 | The Diffie-Hellman parameters are a prime modulus |
549 | .I p |
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550 | and a generator |
551 | .I g |
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552 | of a subgroup of |
553 | .BR Z / \c |
554 | .IB p Z |
555 | of order |
556 | .IR q . |
557 | The |
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558 | .B \-b |
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559 | option controls the size of the modulus |
052b36d0 |
560 | .IR p ; |
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561 | the default size is 1024 bits. |
562 | .IP |
563 | If no |
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564 | .I q |
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565 | size is selected using the |
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566 | .B \-B |
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567 | option and the Lim-Lee prime option is disabled, then |
568 | .I p |
569 | is chosen to be a `safe' prime (i.e., |
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570 | .IR p \ =\ 2 q \ +\ 1, |
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571 | with |
572 | .I q |
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573 | prime). Finding safe primes takes a very long time. In this case, the |
574 | value of |
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575 | .I g |
576 | is fixed as 4. |
577 | .IP |
578 | If a size is chosen for |
579 | .I q |
580 | and Lim-Lee primes are not selected then the prime |
581 | .I q |
582 | is generated and |
583 | .I p |
584 | is chosen so that |
585 | .IR p \ \-\ 1 |
586 | is a multiple of |
587 | .IR q . |
588 | .IP |
589 | If the |
590 | .B \-L |
591 | option was given Lim-Lee primes are selected: the parameters are chosen |
592 | such that |
593 | .IR p \ =\ 2\ q \*(us0\*(ue\ q \*(us1\*(ue\ q \*(us2\*(ue\ ...\ +\ 1, |
594 | where the |
595 | .IR q \*(us i\*(ue |
596 | are primes at least as large as the setting given by the |
597 | .B \-B |
598 | option (or 256 bits, if no setting was given). |
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599 | .IP |
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600 | If the |
601 | .B \-S |
602 | option was given, the generator |
603 | .I g |
604 | is chosen to generate the subgroup of order |
605 | .IR q \*(us0\*(ue; |
606 | otherwise, |
607 | .I g |
608 | will generate the group of order |
609 | .RI ( p \ \-\ 1)/2\ =\ q \*(us0\*(ue\ q \*(us1\*(ue\ q \*(us2\*(ue\ ... |
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610 | .IP |
611 | Finally, the |
612 | .B \-C |
613 | option can be given, in which case the parameters are taken directly |
614 | from the provided group specification, which may either be the the name |
615 | of one of the built-in groups (say |
616 | .B "key add \-a dh\-param \-C list 42" |
617 | for a list) or a triple |
618 | .RI ( p ,\ q ,\ g ). |
619 | separated by commas. No random generation is done in this case: the |
620 | given parameters are simply stored. |
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621 | .TP |
622 | .B "dh" |
623 | Generates a public/private key pair for use with offline Diffie-Hellman, |
624 | ElGamal, DSA or similar discrete-logarithm-based systems. It selects a |
625 | private key |
626 | .IR x \ <\ q , |
627 | and computes the public key |
628 | .IR y \ =\ g\*(ssx\*(se \ mod\ p . |
629 | .TP |
630 | .B "dsa-param" |
631 | Generates parameters for the DSA algorithm. DSA parameters are also |
632 | suitable for use with Diffie-Hellman and ElGamal system. |
633 | .IP |
634 | The main difference between DSA and Diffie-Hellman parameter generation |
635 | is thatthe DSA parameter generation |
636 | algorithm creates a |
637 | .I seed |
638 | from which the parameters are derived, and, assuming that the SHA-1 hash |
639 | function is strong, it's not feasible to construct a seed from which |
640 | deliberately weak parameters are derived. The algorithm used is the one |
641 | described in the DSA standard, FIPS\ 186, extended only to allow |
642 | sequential search for a prime |
643 | .I q |
644 | and to allow arbitrary parameter sizes. The seed is stored, |
645 | Base64-encoded, as the value of the attribute |
646 | .BR seed . |
647 | .IP |
648 | The default lengths for |
649 | .I p |
650 | and |
651 | .I q |
652 | are 768 and 160 bits respectively, since the DSA standard specifies that |
653 | .I q |
654 | be 160 bits, and the choice of 768 bits for |
655 | .I p |
656 | gives commensurate security. |
657 | .TP |
658 | .B "dsa" |
659 | Generates a public/private key pair for DSA. As for Diffie-Hellman |
660 | keys, it selects a |
661 | private key |
662 | .IR x \ <\ q , |
663 | and computes the public key |
664 | .IR y \ =\ g\*(ssx\*(se \ mod\ p . |
665 | .TP |
666 | .B "bbs" |
667 | Generates a public/private key pair for the Blum-Blum-Shub random-number |
668 | generator, and the Blum-Goldwasser semantically-secure public-key |
669 | encryption system. |
670 | .IP |
671 | The key components are prime numbers |
672 | .I p |
673 | and |
674 | .IR q , |
675 | both congruent to 3 (mod\ 4), and their product |
676 | .IR n . |
677 | The public key is simply the modulus |
678 | .IR n ; |
679 | the factors |
680 | .I p |
681 | and |
682 | .I q |
683 | are the private key. |
684 | .IP |
685 | The key-generation algorithm ensures that the two primes |
686 | .I p |
687 | and |
688 | .I q |
689 | are |
690 | .I strong |
691 | (see the discussion of strong primes above, in the section on RSA keys), |
692 | and that |
693 | .RI ( p \ \-\ 1)/2 |
694 | and |
695 | .RI ( q \ \-\ 1)/2 |
696 | are relatively prime, giving a maximum possible period length. |
697 | .IP |
698 | The key size requested by the |
699 | .B \-b |
700 | option determines the length of the modulus |
701 | .IR n ; |
702 | the default length is 1024 bits. |
eb31b00e |
703 | .TP |
704 | .B "ec-param" |
705 | Store an elliptic curve specification. If no explicit |
706 | .I curve-spec |
707 | is given (the |
708 | .RB ` \-C ' |
709 | option) then a curve is chosen whose order is about the size given by the |
710 | .RB ` \-b ' |
711 | option (default is 256 bits). |
712 | .IP |
713 | A |
714 | .I curve-spec |
715 | can be given explicitly (in which case |
716 | .RB ` \-b ' |
717 | is ignored). It can either be the name of a built-in curve (say |
8404fd75 |
718 | .B "key add \-a ec\-param \-C list 42" |
eb31b00e |
719 | for a list of curve names) or a full specification. The curve is |
720 | checked for correctness and security according to the SEC1 |
721 | specification: failed checks cause a warning to be issued to standard |
722 | error (though the program continues anyway). The check can be |
723 | suppressed using the |
724 | .RB ` \-q ' |
725 | option. |
726 | .IP |
727 | A curve specification consists of the following elements optionally |
728 | separated by whitespace: a |
729 | .IR "field type" , |
730 | which is one of |
731 | .BR "prime" , |
732 | .BR "niceprime" , |
8404fd75 |
733 | .BR "binpoly" , |
734 | .or |
735 | .BR "binnorm" ; |
eb31b00e |
736 | an optional |
737 | .RB ` : '; |
738 | the field modulus |
739 | .IR p ; |
8404fd75 |
740 | if the field type is |
741 | .B binnorm |
742 | then an optional |
743 | .RB ` , ' |
744 | and the representation of the normal element \*(*b; an optional |
eb31b00e |
745 | .RB ` / '; |
746 | a |
747 | .IR "curve type" , |
748 | which is one of |
749 | .BR "prime" , |
750 | .BR "primeproj" , |
751 | .BR "bin" , |
752 | and |
753 | .BR "binproj" |
754 | (the `proj' types currently have much better performance); |
755 | an optional |
756 | .RB ` : '; |
757 | the two field-element parameters |
758 | .I a |
759 | and |
760 | .IR b |
761 | which define the elliptic curve |
762 | .IR E , |
763 | separated by an optional |
764 | .RB ` , '; |
765 | an optional |
766 | .RB ` / '; |
767 | the |
768 | .IR x - |
769 | and |
770 | .IR y -coordinates |
771 | of the generator point |
772 | .IR G , |
773 | separated by an optional |
774 | .RB ` , '; |
775 | an optional |
776 | .RB ` : '; |
777 | the order |
778 | .I r |
779 | of the group generated by |
780 | .IR G ; |
781 | an optional |
782 | .RB ` * '; |
783 | and the |
784 | .I cofactor |
785 | .I h |
786 | = |
787 | .RI # E / r . |
788 | .TP |
789 | .B "ec" |
790 | Generate a private scalar and a corresponding public point on an |
791 | elliptic curve. See |
792 | .B ec-param |
793 | above for how to specify elliptic curve parameter sets. The scalar |
794 | .I x |
795 | is chosen unformly between 0 and the curve order |
796 | .IR r ; |
797 | the public point is then |
798 | .I x |
799 | \(mu |
800 | .IR G . |
052b36d0 |
801 | .SS "expire" |
d03ab969 |
802 | Forces keys to immediately expire. An expired key is not chosen when a |
803 | program requests a key by its type. The keys to expire are listed by |
804 | their |
052b36d0 |
805 | .IR tag s. |
806 | .SS "delete" |
d03ab969 |
807 | Deletes keys immediately. The keys to delete are listed by their |
052b36d0 |
808 | .IR tag s. |
d03ab969 |
809 | Be careful when deleting keys. It might be a better idea |
810 | to expire keys rather than deleting them. |
052b36d0 |
811 | .SS "tag" |
812 | Sets, deletes or changes the tag attached to a key. The first tag or |
813 | keyid names the key to be modified; the second, if present specifies the |
814 | new tag to be set. If no second argument is given, the existing tag, if |
d07dfe80 |
815 | any, is removed and no new tag is set. It is an error to set a tag |
816 | which already exists on another key, unless you give the |
817 | .B \-r |
818 | option, which removes the tag first. |
052b36d0 |
819 | .SS "setattr" |
d03ab969 |
820 | Attaches attributes to a key. The key to which the attributes should be |
821 | attached is given by its |
052b36d0 |
822 | .IR tag . |
d03ab969 |
823 | Each attribute has the form |
824 | .IB name = value\fR. |
825 | An attribute can be deleted by assigning it an empty value. Although |
826 | the keyring file format is capable of representing an attribute with an |
827 | empty value as distinct from a nonexistant attribute, this interface |
828 | does not allow empty attributes to be set. |
052b36d0 |
829 | .SS "comment" |
830 | Sets, deletes or changes the comment attached to a key. The first |
831 | argument is a key tag or keyid which names the key to be modified; the |
832 | second, if present, is the new comment. If no second argument is given, |
833 | the existing comment, if any, is removed, and no new comment is set. |
834 | .SS "lock" |
835 | Locks a key or key component using a passphrase. If the key is already |
836 | locked, the existing passphrase is requested, and a new passphrase is |
837 | set. |
838 | .SS "unlock" |
839 | Unlocks a passphrase-locked key or key component. If the key is not |
840 | locked, an error is reported. |
841 | .SS "list" |
d03ab969 |
842 | Lists the keys in the keyring. A couple of options are supported: |
843 | .TP |
844 | .B "\-v, \-\-verbose" |
845 | Increases the amount of information displayed for each key. Repeat for |
846 | a greater effect. |
847 | .TP |
848 | .B "\-q, \-\-quiet" |
849 | Decreases the amount of information displayed for each key. Each use |
850 | cancels a |
851 | .RB ` \-v ' |
852 | option. |
c9e31e42 |
853 | .TP |
854 | .B "\-u, \-\-utc" |
855 | Display key expiry times as UTC rather than using the local time zone. |
052b36d0 |
856 | .TP |
857 | .BI "\-f, \-\-filter " filter |
858 | Specifies a filter. Only keys and key components which match the filter |
859 | are listed. |
d03ab969 |
860 | .PP |
861 | By default, a single line of output is generated for each, showing |
862 | keyids, types, expiry and deletion dates, and comments. Additional |
863 | .RB ` \-v ' |
864 | options show more information, such as the exact time of day for expiry |
052b36d0 |
865 | and deletion, key attributes, and a dump of the actual key data. If the |
866 | verbosity level is sufficiently high, passphrases are requested to |
867 | decrypt locked keys. Make sure nobody is looking over your shoulder |
868 | when you do this! |
869 | .SS "fingerprint" |
870 | Reports a fingerprint (secure hash) on components of requested keys. |
871 | The following option is supported: |
872 | .TP |
873 | .BI "\-f, \-\-filter " filter |
874 | Specifies a filter. Only keys and key components which match the filter |
875 | are fingerprinted. The default is to only fingerprint nonsecret |
876 | components. |
b817bfc6 |
877 | .TP |
878 | .BI "\-a, \-\-algorithm " hash |
879 | Names the hashing algorithm. Run |
880 | .B hashsum -a list |
881 | for a list of hashing algorithms. The default is |
882 | .BR rmd160 . |
052b36d0 |
883 | .PP |
884 | The keys to be fingerprinted are named by their tags or keyids given as |
885 | command line arguments. If no key tags are given, all keys which match |
b817bfc6 |
886 | the filter are fingerprinted. See |
887 | .BR keyring (5) |
888 | for a description of how key fingerprints are computed. |
052b36d0 |
889 | .SS "tidy" |
d03ab969 |
890 | Simply reads the keyring from file and writes it back again. This has |
891 | the effect of removing any deleted keys from the file. |
052b36d0 |
892 | .SS "extract" |
893 | Writes a selection of keys to a file. An option is supported: |
894 | .TP |
895 | .BI "\-f, \-\-filter " filter |
896 | Specifies a filter. Only keys and key components which match the filter |
897 | are written. |
898 | .PP |
899 | Keys extracted are written to the file named by the first argument, |
d03ab969 |
900 | which may be |
901 | .RB ` \- ' |
902 | to designate standard output. The keys to extract are listed by their |
052b36d0 |
903 | tags; if no tags are given, all keys which match the filter are |
904 | extracted. The output is a valid keyring file. |
905 | .SS "merge" |
d03ab969 |
906 | Merges the keys from the named |
907 | .IR file , |
908 | which may be |
909 | .RB ` \- ' |
910 | to designate standard input, with the keyring. Keys already in the |
911 | keyring are not overwritten: you must explicitly remove them first if |
912 | you want them to be replaced during the merge. |
d03ab969 |
913 | .SH "SEE ALSO" |
914 | .BR keyring (5). |
915 | .SH AUTHOR |
916 | Mark Wooding, <mdw@nsict.org> |
917 | |