Annotation of src/usr.bin/ssh/ssh-keygen.1, Revision 1.97
1.97 ! schwarze 1: .\" $OpenBSD: ssh-keygen.1,v 1.96 2010/06/30 07:24:25 jmc Exp $
1.29 niklas 2: .\"
1.1 deraadt 3: .\" -*- nroff -*-
4: .\"
5: .\" Author: Tatu Ylonen <ylo@cs.hut.fi>
6: .\" Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
7: .\" All rights reserved
8: .\"
1.22 deraadt 9: .\" As far as I am concerned, the code I have written for this software
10: .\" can be used freely for any purpose. Any derived versions of this
11: .\" software must be clearly marked as such, and if the derived work is
12: .\" incompatible with the protocol description in the RFC file, it must be
13: .\" called by a name other than "ssh" or "Secure Shell".
14: .\"
15: .\"
1.33 deraadt 16: .\" Copyright (c) 1999,2000 Markus Friedl. All rights reserved.
17: .\" Copyright (c) 1999 Aaron Campbell. All rights reserved.
18: .\" Copyright (c) 1999 Theo de Raadt. All rights reserved.
1.22 deraadt 19: .\"
20: .\" Redistribution and use in source and binary forms, with or without
21: .\" modification, are permitted provided that the following conditions
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1.1 deraadt 28: .\"
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30: .\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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1.97 ! schwarze 40: .Dd $Mdocdate: June 30 2010 $
1.2 deraadt 41: .Dt SSH-KEYGEN 1
42: .Os
43: .Sh NAME
44: .Nm ssh-keygen
1.37 markus 45: .Nd authentication key generation, management and conversion
1.2 deraadt 46: .Sh SYNOPSIS
1.97 ! schwarze 47: .Bk -words
1.2 deraadt 48: .Nm ssh-keygen
1.25 markus 49: .Op Fl q
1.2 deraadt 50: .Op Fl b Ar bits
1.53 stevesk 51: .Fl t Ar type
1.2 deraadt 52: .Op Fl N Ar new_passphrase
53: .Op Fl C Ar comment
1.20 markus 54: .Op Fl f Ar output_keyfile
1.2 deraadt 55: .Nm ssh-keygen
56: .Fl p
57: .Op Fl P Ar old_passphrase
58: .Op Fl N Ar new_passphrase
1.9 markus 59: .Op Fl f Ar keyfile
1.2 deraadt 60: .Nm ssh-keygen
1.37 markus 61: .Fl i
1.95 djm 62: .Op Fl m Ar key_format
1.20 markus 63: .Op Fl f Ar input_keyfile
1.16 deraadt 64: .Nm ssh-keygen
1.37 markus 65: .Fl e
1.95 djm 66: .Op Fl m Ar key_format
1.20 markus 67: .Op Fl f Ar input_keyfile
1.16 deraadt 68: .Nm ssh-keygen
1.17 markus 69: .Fl y
1.20 markus 70: .Op Fl f Ar input_keyfile
1.17 markus 71: .Nm ssh-keygen
1.2 deraadt 72: .Fl c
73: .Op Fl P Ar passphrase
74: .Op Fl C Ar comment
1.9 markus 75: .Op Fl f Ar keyfile
76: .Nm ssh-keygen
77: .Fl l
1.35 markus 78: .Op Fl f Ar input_keyfile
79: .Nm ssh-keygen
80: .Fl B
1.20 markus 81: .Op Fl f Ar input_keyfile
1.48 jakob 82: .Nm ssh-keygen
1.82 jmc 83: .Fl D Ar pkcs11
1.48 jakob 84: .Nm ssh-keygen
1.64 djm 85: .Fl F Ar hostname
86: .Op Fl f Ar known_hosts_file
1.79 sthen 87: .Op Fl l
1.64 djm 88: .Nm ssh-keygen
89: .Fl H
90: .Op Fl f Ar known_hosts_file
91: .Nm ssh-keygen
92: .Fl R Ar hostname
93: .Op Fl f Ar known_hosts_file
1.57 jakob 94: .Nm ssh-keygen
95: .Fl r Ar hostname
96: .Op Fl f Ar input_keyfile
97: .Op Fl g
1.60 djm 98: .Nm ssh-keygen
99: .Fl G Ar output_file
1.61 djm 100: .Op Fl v
1.60 djm 101: .Op Fl b Ar bits
102: .Op Fl M Ar memory
103: .Op Fl S Ar start_point
104: .Nm ssh-keygen
105: .Fl T Ar output_file
106: .Fl f Ar input_file
1.61 djm 107: .Op Fl v
1.60 djm 108: .Op Fl a Ar num_trials
109: .Op Fl W Ar generator
1.84 djm 110: .Nm ssh-keygen
111: .Fl s Ar ca_key
112: .Fl I Ar certificate_identity
113: .Op Fl h
114: .Op Fl n Ar principals
1.93 djm 115: .Op Fl O Ar option
1.84 djm 116: .Op Fl V Ar validity_interval
1.93 djm 117: .Op Fl z Ar serial_number
1.84 djm 118: .Ar
1.86 djm 119: .Nm ssh-keygen
120: .Fl L
121: .Op Fl f Ar input_keyfile
1.85 jmc 122: .Ek
1.13 aaron 123: .Sh DESCRIPTION
1.2 deraadt 124: .Nm
1.37 markus 125: generates, manages and converts authentication keys for
1.2 deraadt 126: .Xr ssh 1 .
1.15 deraadt 127: .Nm
1.54 deraadt 128: can create RSA keys for use by SSH protocol version 1 and RSA or DSA
1.58 jmc 129: keys for use by SSH protocol version 2.
130: The type of key to be generated is specified with the
1.25 markus 131: .Fl t
1.52 djm 132: option.
1.70 djm 133: If invoked without any arguments,
134: .Nm
1.71 jmc 135: will generate an RSA key for use in SSH protocol 2 connections.
1.15 deraadt 136: .Pp
1.60 djm 137: .Nm
138: is also used to generate groups for use in Diffie-Hellman group
139: exchange (DH-GEX).
140: See the
141: .Sx MODULI GENERATION
142: section for details.
143: .Pp
1.2 deraadt 144: Normally each user wishing to use SSH
1.15 deraadt 145: with RSA or DSA authentication runs this once to create the authentication
1.1 deraadt 146: key in
1.68 djm 147: .Pa ~/.ssh/identity ,
148: .Pa ~/.ssh/id_dsa
1.15 deraadt 149: or
1.68 djm 150: .Pa ~/.ssh/id_rsa .
1.15 deraadt 151: Additionally, the system administrator may use this to generate host keys,
152: as seen in
153: .Pa /etc/rc .
1.2 deraadt 154: .Pp
1.1 deraadt 155: Normally this program generates the key and asks for a file in which
1.12 aaron 156: to store the private key.
157: The public key is stored in a file with the same name but
1.2 deraadt 158: .Dq .pub
1.12 aaron 159: appended.
160: The program also asks for a passphrase.
161: The passphrase may be empty to indicate no passphrase
1.26 markus 162: (host keys must have an empty passphrase), or it may be a string of
1.12 aaron 163: arbitrary length.
1.51 stevesk 164: A passphrase is similar to a password, except it can be a phrase with a
165: series of words, punctuation, numbers, whitespace, or any string of
166: characters you want.
167: Good passphrases are 10-30 characters long, are
1.1 deraadt 168: not simple sentences or otherwise easily guessable (English
1.42 markus 169: prose has only 1-2 bits of entropy per character, and provides very bad
1.51 stevesk 170: passphrases), and contain a mix of upper and lowercase letters,
171: numbers, and non-alphanumeric characters.
1.12 aaron 172: The passphrase can be changed later by using the
1.2 deraadt 173: .Fl p
1.1 deraadt 174: option.
1.2 deraadt 175: .Pp
1.12 aaron 176: There is no way to recover a lost passphrase.
177: If the passphrase is
1.49 deraadt 178: lost or forgotten, a new key must be generated and copied to the
1.1 deraadt 179: corresponding public key to other machines.
1.2 deraadt 180: .Pp
1.37 markus 181: For RSA1 keys,
182: there is also a comment field in the key file that is only for
1.12 aaron 183: convenience to the user to help identify the key.
184: The comment can tell what the key is for, or whatever is useful.
185: The comment is initialized to
1.2 deraadt 186: .Dq user@host
187: when the key is created, but can be changed using the
188: .Fl c
1.1 deraadt 189: option.
1.2 deraadt 190: .Pp
1.15 deraadt 191: After a key is generated, instructions below detail where the keys
192: should be placed to be activated.
193: .Pp
1.2 deraadt 194: The options are as follows:
195: .Bl -tag -width Ds
1.60 djm 196: .It Fl a Ar trials
197: Specifies the number of primality tests to perform when screening DH-GEX
198: candidates using the
199: .Fl T
200: command.
1.66 jmc 201: .It Fl B
202: Show the bubblebabble digest of specified private or public key file.
1.2 deraadt 203: .It Fl b Ar bits
1.12 aaron 204: Specifies the number of bits in the key to create.
1.72 dtucker 205: For RSA keys, the minimum size is 768 bits and the default is 2048 bits.
1.69 djm 206: Generally, 2048 bits is considered sufficient.
1.72 dtucker 207: DSA keys must be exactly 1024 bits as specified by FIPS 186-2.
1.66 jmc 208: .It Fl C Ar comment
209: Provides a new comment.
1.2 deraadt 210: .It Fl c
1.1 deraadt 211: Requests changing the comment in the private and public key files.
1.50 markus 212: This operation is only supported for RSA1 keys.
1.1 deraadt 213: The program will prompt for the file containing the private keys, for
1.41 stevesk 214: the passphrase if the key has one, and for the new comment.
1.81 markus 215: .It Fl D Ar pkcs11
1.83 markus 216: Download the RSA public keys provided by the PKCS#11 shared library
217: .Ar pkcs11 .
1.37 markus 218: .It Fl e
1.40 markus 219: This option will read a private or public OpenSSH key file and
1.95 djm 220: print to stdout the key in one of the formats specified by the
221: .Fl m
222: option.
223: The default export format is
224: .Dq RFC4716 .
1.96 jmc 225: This option allows exporting OpenSSH keys for use by other programs, including
1.95 djm 226: several commercial SSH implementations.
1.66 jmc 227: .It Fl F Ar hostname
228: Search for the specified
229: .Ar hostname
230: in a
231: .Pa known_hosts
232: file, listing any occurrences found.
233: This option is useful to find hashed host names or addresses and may also be
234: used in conjunction with the
235: .Fl H
236: option to print found keys in a hashed format.
237: .It Fl f Ar filename
238: Specifies the filename of the key file.
239: .It Fl G Ar output_file
240: Generate candidate primes for DH-GEX.
241: These primes must be screened for
242: safety (using the
243: .Fl T
244: option) before use.
1.57 jakob 245: .It Fl g
1.62 jakob 246: Use generic DNS format when printing fingerprint resource records using the
1.63 jmc 247: .Fl r
1.62 jakob 248: command.
1.66 jmc 249: .It Fl H
250: Hash a
251: .Pa known_hosts
1.67 dtucker 252: file.
253: This replaces all hostnames and addresses with hashed representations
254: within the specified file; the original content is moved to a file with
255: a .old suffix.
1.66 jmc 256: These hashes may be used normally by
257: .Nm ssh
258: and
259: .Nm sshd ,
260: but they do not reveal identifying information should the file's contents
261: be disclosed.
262: This option will not modify existing hashed hostnames and is therefore safe
263: to use on files that mix hashed and non-hashed names.
1.84 djm 264: .It Fl h
265: When signing a key, create a host certificate instead of a user
266: certificate.
267: Please see the
268: .Sx CERTIFICATES
269: section for details.
1.85 jmc 270: .It Fl I Ar certificate_identity
1.84 djm 271: Specify the key identity when signing a public key.
272: Please see the
273: .Sx CERTIFICATES
274: section for details.
1.37 markus 275: .It Fl i
276: This option will read an unencrypted private (or public) key file
1.95 djm 277: in the format specified by the
278: .Fl m
279: option and print an OpenSSH compatible private
1.37 markus 280: (or public) key to stdout.
1.95 djm 281: This option allows importing keys from other software, including several
282: commercial SSH implementations.
283: The default import format is
284: .Dq RFC4716 .
1.86 djm 285: .It Fl L
286: Prints the contents of a certificate.
1.9 markus 287: .It Fl l
1.77 grunk 288: Show fingerprint of specified public key file.
1.50 markus 289: Private RSA1 keys are also supported.
290: For RSA and DSA keys
291: .Nm
1.78 jmc 292: tries to find the matching public key file and prints its fingerprint.
293: If combined with
294: .Fl v ,
295: an ASCII art representation of the key is supplied with the fingerprint.
1.96 jmc 296: .It Fl M Ar memory
297: Specify the amount of memory to use (in megabytes) when generating
298: candidate moduli for DH-GEX.
1.95 djm 299: .It Fl m Ar key_format
300: Specify a key format for the
301: .Fl i
302: (import) or
303: .Fl e
1.96 jmc 304: (export) conversion options.
1.95 djm 305: The supported key formats are:
306: .Dq RFC4716
1.96 jmc 307: (RFC 4716/SSH2 public or private key),
1.95 djm 308: .Dq PKCS8
309: (PEM PKCS8 public key)
310: or
311: .Dq PEM
312: (PEM public key).
313: The default conversion format is
314: .Dq RFC4716 .
1.66 jmc 315: .It Fl N Ar new_passphrase
316: Provides the new passphrase.
1.84 djm 317: .It Fl n Ar principals
318: Specify one or more principals (user or host names) to be included in
319: a certificate when signing a key.
320: Multiple principals may be specified, separated by commas.
321: Please see the
322: .Sx CERTIFICATES
323: section for details.
1.93 djm 324: .It Fl O Ar option
325: Specify a certificate option when signing a key.
1.84 djm 326: This option may be specified multiple times.
327: Please see the
328: .Sx CERTIFICATES
329: section for details.
1.93 djm 330: The options that are valid for user certificates are:
1.84 djm 331: .Bl -tag -width Ds
1.89 jmc 332: .It Ic clear
333: Clear all enabled permissions.
334: This is useful for clearing the default set of permissions so permissions may
335: be added individually.
336: .It Ic force-command Ns = Ns Ar command
337: Forces the execution of
338: .Ar command
339: instead of any shell or command specified by the user when
340: the certificate is used for authentication.
1.84 djm 341: .It Ic no-agent-forwarding
342: Disable
343: .Xr ssh-agent 1
1.85 jmc 344: forwarding (permitted by default).
1.84 djm 345: .It Ic no-port-forwarding
1.85 jmc 346: Disable port forwarding (permitted by default).
1.84 djm 347: .It Ic no-pty
1.85 jmc 348: Disable PTY allocation (permitted by default).
1.84 djm 349: .It Ic no-user-rc
350: Disable execution of
351: .Pa ~/.ssh/rc
352: by
1.85 jmc 353: .Xr sshd 8
354: (permitted by default).
1.89 jmc 355: .It Ic no-x11-forwarding
356: Disable X11 forwarding (permitted by default).
1.88 djm 357: .It Ic permit-agent-forwarding
358: Allows
359: .Xr ssh-agent 1
360: forwarding.
1.84 djm 361: .It Ic permit-port-forwarding
362: Allows port forwarding.
363: .It Ic permit-pty
364: Allows PTY allocation.
365: .It Ic permit-user-rc
366: Allows execution of
367: .Pa ~/.ssh/rc
368: by
369: .Xr sshd 8 .
1.89 jmc 370: .It Ic permit-x11-forwarding
371: Allows X11 forwarding.
372: .It Ic source-address Ns = Ns Ar address_list
1.90 jmc 373: Restrict the source addresses from which the certificate is considered valid.
1.84 djm 374: The
375: .Ar address_list
376: is a comma-separated list of one or more address/netmask pairs in CIDR
377: format.
378: .El
379: .Pp
1.93 djm 380: At present, no options are valid for host keys.
1.66 jmc 381: .It Fl P Ar passphrase
382: Provides the (old) passphrase.
1.2 deraadt 383: .It Fl p
1.1 deraadt 384: Requests changing the passphrase of a private key file instead of
1.12 aaron 385: creating a new private key.
386: The program will prompt for the file
1.1 deraadt 387: containing the private key, for the old passphrase, and twice for the
388: new passphrase.
1.5 aaron 389: .It Fl q
390: Silence
391: .Nm ssh-keygen .
392: Used by
393: .Pa /etc/rc
394: when creating a new key.
1.64 djm 395: .It Fl R Ar hostname
396: Removes all keys belonging to
397: .Ar hostname
1.65 jmc 398: from a
1.64 djm 399: .Pa known_hosts
400: file.
1.65 jmc 401: This option is useful to delete hashed hosts (see the
1.64 djm 402: .Fl H
403: option above).
1.66 jmc 404: .It Fl r Ar hostname
405: Print the SSHFP fingerprint resource record named
406: .Ar hostname
407: for the specified public key file.
1.60 djm 408: .It Fl S Ar start
409: Specify start point (in hex) when generating candidate moduli for DH-GEX.
1.84 djm 410: .It Fl s Ar ca_key
411: Certify (sign) a public key using the specified CA key.
412: Please see the
413: .Sx CERTIFICATES
414: section for details.
1.60 djm 415: .It Fl T Ar output_file
416: Test DH group exchange candidate primes (generated using the
417: .Fl G
418: option) for safety.
1.66 jmc 419: .It Fl t Ar type
420: Specifies the type of key to create.
421: The possible values are
422: .Dq rsa1
423: for protocol version 1 and
424: .Dq rsa
425: or
426: .Dq dsa
427: for protocol version 2.
1.84 djm 428: .It Fl V Ar validity_interval
429: Specify a validity interval when signing a certificate.
430: A validity interval may consist of a single time, indicating that the
431: certificate is valid beginning now and expiring at that time, or may consist
432: of two times separated by a colon to indicate an explicit time interval.
433: The start time may be specified as a date in YYYYMMDD format, a time
434: in YYYYMMDDHHMMSS format or a relative time (to the current time) consisting
435: of a minus sign followed by a relative time in the format described in the
436: .Sx TIME FORMATS
437: section of
1.90 jmc 438: .Xr sshd_config 5 .
1.84 djm 439: The end time may be specified as a YYYYMMDD date, a YYYYMMDDHHMMSS time or
440: a relative time starting with a plus character.
441: .Pp
442: For example:
443: .Dq +52w1d
444: (valid from now to 52 weeks and one day from now),
445: .Dq -4w:+4w
446: (valid from four weeks ago to four weeks from now),
447: .Dq 20100101123000:20110101123000
448: (valid from 12:30 PM, January 1st, 2010 to 12:30 PM, January 1st, 2011),
449: .Dq -1d:20110101
450: (valid from yesterday to midnight, January 1st, 2011).
1.61 djm 451: .It Fl v
452: Verbose mode.
453: Causes
454: .Nm
455: to print debugging messages about its progress.
456: This is helpful for debugging moduli generation.
457: Multiple
458: .Fl v
459: options increase the verbosity.
460: The maximum is 3.
1.66 jmc 461: .It Fl W Ar generator
462: Specify desired generator when testing candidate moduli for DH-GEX.
463: .It Fl y
464: This option will read a private
465: OpenSSH format file and print an OpenSSH public key to stdout.
1.93 djm 466: .It Fl z Ar serial_number
467: Specifies a serial number to be embedded in the certificate to distinguish
468: this certificate from others from the same CA.
469: The default serial number is zero.
1.2 deraadt 470: .El
1.60 djm 471: .Sh MODULI GENERATION
472: .Nm
473: may be used to generate groups for the Diffie-Hellman Group Exchange
474: (DH-GEX) protocol.
475: Generating these groups is a two-step process: first, candidate
476: primes are generated using a fast, but memory intensive process.
477: These candidate primes are then tested for suitability (a CPU-intensive
478: process).
479: .Pp
480: Generation of primes is performed using the
481: .Fl G
482: option.
483: The desired length of the primes may be specified by the
484: .Fl b
485: option.
486: For example:
487: .Pp
1.66 jmc 488: .Dl # ssh-keygen -G moduli-2048.candidates -b 2048
1.60 djm 489: .Pp
490: By default, the search for primes begins at a random point in the
491: desired length range.
492: This may be overridden using the
493: .Fl S
494: option, which specifies a different start point (in hex).
495: .Pp
496: Once a set of candidates have been generated, they must be tested for
497: suitability.
498: This may be performed using the
499: .Fl T
500: option.
501: In this mode
502: .Nm
503: will read candidates from standard input (or a file specified using the
504: .Fl f
505: option).
506: For example:
507: .Pp
1.66 jmc 508: .Dl # ssh-keygen -T moduli-2048 -f moduli-2048.candidates
1.60 djm 509: .Pp
510: By default, each candidate will be subjected to 100 primality tests.
511: This may be overridden using the
512: .Fl a
513: option.
514: The DH generator value will be chosen automatically for the
515: prime under consideration.
516: If a specific generator is desired, it may be requested using the
517: .Fl W
518: option.
1.66 jmc 519: Valid generator values are 2, 3, and 5.
1.60 djm 520: .Pp
521: Screened DH groups may be installed in
522: .Pa /etc/moduli .
523: It is important that this file contains moduli of a range of bit lengths and
524: that both ends of a connection share common moduli.
1.84 djm 525: .Sh CERTIFICATES
526: .Nm
527: supports signing of keys to produce certificates that may be used for
528: user or host authentication.
529: Certificates consist of a public key, some identity information, zero or
1.94 jmc 530: more principal (user or host) names and a set of options that
1.84 djm 531: are signed by a Certification Authority (CA) key.
532: Clients or servers may then trust only the CA key and verify its signature
533: on a certificate rather than trusting many user/host keys.
534: Note that OpenSSH certificates are a different, and much simpler, format to
535: the X.509 certificates used in
536: .Xr ssl 8 .
537: .Pp
538: .Nm
539: supports two types of certificates: user and host.
540: User certificates authenticate users to servers, whereas host certificates
1.85 jmc 541: authenticate server hosts to users.
542: To generate a user certificate:
1.84 djm 543: .Pp
544: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id /path/to/user_key.pub
545: .Pp
546: The resultant certificate will be placed in
1.91 djm 547: .Pa /path/to/user_key-cert.pub .
1.84 djm 548: A host certificate requires the
549: .Fl h
550: option:
551: .Pp
552: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id -h /path/to/host_key.pub
553: .Pp
554: The host certificate will be output to
1.91 djm 555: .Pa /path/to/host_key-cert.pub .
1.84 djm 556: In both cases,
557: .Ar key_id
558: is a "key identifier" that is logged by the server when the certificate
559: is used for authentication.
560: .Pp
561: Certificates may be limited to be valid for a set of principal (user/host)
562: names.
563: By default, generated certificates are valid for all users or hosts.
564: To generate a certificate for a specified set of principals:
565: .Pp
566: .Dl $ ssh-keygen -s ca_key -I key_id -n user1,user2 user_key.pub
1.92 jmc 567: .Dl "$ ssh-keygen -s ca_key -I key_id -h -n host.domain user_key.pub"
1.84 djm 568: .Pp
569: Additional limitations on the validity and use of user certificates may
1.94 jmc 570: be specified through certificate options.
1.93 djm 571: A certificate option may disable features of the SSH session, may be
1.84 djm 572: valid only when presented from particular source addresses or may
573: force the use of a specific command.
1.93 djm 574: For a list of valid certificate options, see the documentation for the
1.84 djm 575: .Fl O
576: option above.
577: .Pp
578: Finally, certificates may be defined with a validity lifetime.
579: The
580: .Fl V
581: option allows specification of certificate start and end times.
582: A certificate that is presented at a time outside this range will not be
583: considered valid.
584: By default, certificates have a maximum validity interval.
585: .Pp
586: For certificates to be used for user or host authentication, the CA
587: public key must be trusted by
588: .Xr sshd 8
589: or
590: .Xr ssh 1 .
591: Please refer to those manual pages for details.
1.2 deraadt 592: .Sh FILES
593: .Bl -tag -width Ds
1.68 djm 594: .It Pa ~/.ssh/identity
1.36 itojun 595: Contains the protocol version 1 RSA authentication identity of the user.
1.12 aaron 596: This file should not be readable by anyone but the user.
597: It is possible to
1.1 deraadt 598: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 599: used to encrypt the private part of this file using 128-bit AES.
1.12 aaron 600: This file is not automatically accessed by
1.2 deraadt 601: .Nm
1.1 deraadt 602: but it is offered as the default file for the private key.
1.46 markus 603: .Xr ssh 1
1.15 deraadt 604: will read this file when a login attempt is made.
1.68 djm 605: .It Pa ~/.ssh/identity.pub
1.36 itojun 606: Contains the protocol version 1 RSA public key for authentication.
1.12 aaron 607: The contents of this file should be added to
1.68 djm 608: .Pa ~/.ssh/authorized_keys
1.2 deraadt 609: on all machines
1.49 deraadt 610: where the user wishes to log in using RSA authentication.
1.15 deraadt 611: There is no need to keep the contents of this file secret.
1.68 djm 612: .It Pa ~/.ssh/id_dsa
1.36 itojun 613: Contains the protocol version 2 DSA authentication identity of the user.
1.15 deraadt 614: This file should not be readable by anyone but the user.
615: It is possible to
616: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 617: used to encrypt the private part of this file using 128-bit AES.
1.15 deraadt 618: This file is not automatically accessed by
619: .Nm
620: but it is offered as the default file for the private key.
1.46 markus 621: .Xr ssh 1
1.15 deraadt 622: will read this file when a login attempt is made.
1.68 djm 623: .It Pa ~/.ssh/id_dsa.pub
1.36 itojun 624: Contains the protocol version 2 DSA public key for authentication.
625: The contents of this file should be added to
1.68 djm 626: .Pa ~/.ssh/authorized_keys
1.36 itojun 627: on all machines
1.49 deraadt 628: where the user wishes to log in using public key authentication.
1.36 itojun 629: There is no need to keep the contents of this file secret.
1.68 djm 630: .It Pa ~/.ssh/id_rsa
1.36 itojun 631: Contains the protocol version 2 RSA authentication identity of the user.
632: This file should not be readable by anyone but the user.
633: It is possible to
634: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 635: used to encrypt the private part of this file using 128-bit AES.
1.36 itojun 636: This file is not automatically accessed by
637: .Nm
638: but it is offered as the default file for the private key.
1.46 markus 639: .Xr ssh 1
1.36 itojun 640: will read this file when a login attempt is made.
1.68 djm 641: .It Pa ~/.ssh/id_rsa.pub
1.36 itojun 642: Contains the protocol version 2 RSA public key for authentication.
1.15 deraadt 643: The contents of this file should be added to
1.68 djm 644: .Pa ~/.ssh/authorized_keys
1.15 deraadt 645: on all machines
1.49 deraadt 646: where the user wishes to log in using public key authentication.
1.12 aaron 647: There is no need to keep the contents of this file secret.
1.60 djm 648: .It Pa /etc/moduli
649: Contains Diffie-Hellman groups used for DH-GEX.
650: The file format is described in
651: .Xr moduli 5 .
1.19 aaron 652: .El
1.2 deraadt 653: .Sh SEE ALSO
654: .Xr ssh 1 ,
655: .Xr ssh-add 1 ,
1.8 ericj 656: .Xr ssh-agent 1 ,
1.60 djm 657: .Xr moduli 5 ,
1.30 itojun 658: .Xr sshd 8
1.37 markus 659: .Rs
1.73 markus 660: .%R RFC 4716
661: .%T "The Secure Shell (SSH) Public Key File Format"
662: .%D 2006
1.37 markus 663: .Re
1.59 jmc 664: .Sh AUTHORS
665: OpenSSH is a derivative of the original and free
666: ssh 1.2.12 release by Tatu Ylonen.
667: Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
668: Theo de Raadt and Dug Song
669: removed many bugs, re-added newer features and
670: created OpenSSH.
671: Markus Friedl contributed the support for SSH
672: protocol versions 1.5 and 2.0.
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