Annotation of src/usr.bin/ssh/ssh-keygen.1, Revision 1.84
1.84 ! djm 1: .\" $OpenBSD: ssh-keygen.1,v 1.83 2010/02/10 23:20:38 markus 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
22: .\" are met:
23: .\" 1. Redistributions of source code must retain the above copyright
24: .\" notice, this list of conditions and the following disclaimer.
25: .\" 2. Redistributions in binary form must reproduce the above copyright
26: .\" notice, this list of conditions and the following disclaimer in the
27: .\" documentation and/or other materials provided with the distribution.
1.1 deraadt 28: .\"
1.22 deraadt 29: .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
30: .\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
31: .\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
32: .\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
33: .\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
34: .\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35: .\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36: .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37: .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
38: .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.1 deraadt 39: .\"
1.84 ! djm 40: .Dd $Mdocdate: February 10 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
47: .Nm ssh-keygen
1.56 jmc 48: .Bk -words
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
1.56 jmc 55: .Ek
1.2 deraadt 56: .Nm ssh-keygen
57: .Fl p
58: .Op Fl P Ar old_passphrase
59: .Op Fl N Ar new_passphrase
1.9 markus 60: .Op Fl f Ar keyfile
1.2 deraadt 61: .Nm ssh-keygen
1.37 markus 62: .Fl i
1.20 markus 63: .Op Fl f Ar input_keyfile
1.16 deraadt 64: .Nm ssh-keygen
1.37 markus 65: .Fl e
1.20 markus 66: .Op Fl f Ar input_keyfile
1.16 deraadt 67: .Nm ssh-keygen
1.17 markus 68: .Fl y
1.20 markus 69: .Op Fl f Ar input_keyfile
1.17 markus 70: .Nm ssh-keygen
1.2 deraadt 71: .Fl c
72: .Op Fl P Ar passphrase
73: .Op Fl C Ar comment
1.9 markus 74: .Op Fl f Ar keyfile
75: .Nm ssh-keygen
76: .Fl l
1.35 markus 77: .Op Fl f Ar input_keyfile
78: .Nm ssh-keygen
79: .Fl B
1.20 markus 80: .Op Fl f Ar input_keyfile
1.48 jakob 81: .Nm ssh-keygen
1.82 jmc 82: .Fl D Ar pkcs11
1.48 jakob 83: .Nm ssh-keygen
1.64 djm 84: .Fl F Ar hostname
85: .Op Fl f Ar known_hosts_file
1.79 sthen 86: .Op Fl l
1.64 djm 87: .Nm ssh-keygen
88: .Fl H
89: .Op Fl f Ar known_hosts_file
90: .Nm ssh-keygen
91: .Fl R Ar hostname
92: .Op Fl f Ar known_hosts_file
1.57 jakob 93: .Nm ssh-keygen
94: .Fl r Ar hostname
95: .Op Fl f Ar input_keyfile
96: .Op Fl g
1.60 djm 97: .Nm ssh-keygen
98: .Fl G Ar output_file
1.61 djm 99: .Op Fl v
1.60 djm 100: .Op Fl b Ar bits
101: .Op Fl M Ar memory
102: .Op Fl S Ar start_point
103: .Nm ssh-keygen
104: .Fl T Ar output_file
105: .Fl f Ar input_file
1.61 djm 106: .Op Fl v
1.60 djm 107: .Op Fl a Ar num_trials
108: .Op Fl W Ar generator
1.84 ! djm 109: .Nm ssh-keygen
! 110: .Fl s Ar ca_key
! 111: .Fl I Ar certificate_identity
! 112: .Op Fl h
! 113: .Op Fl n Ar principals
! 114: .Op Fl O Ar constraint
! 115: .Op Fl V Ar validity_interval
! 116: .Ar
1.13 aaron 117: .Sh DESCRIPTION
1.2 deraadt 118: .Nm
1.37 markus 119: generates, manages and converts authentication keys for
1.2 deraadt 120: .Xr ssh 1 .
1.15 deraadt 121: .Nm
1.54 deraadt 122: can create RSA keys for use by SSH protocol version 1 and RSA or DSA
1.58 jmc 123: keys for use by SSH protocol version 2.
124: The type of key to be generated is specified with the
1.25 markus 125: .Fl t
1.52 djm 126: option.
1.70 djm 127: If invoked without any arguments,
128: .Nm
1.71 jmc 129: will generate an RSA key for use in SSH protocol 2 connections.
1.15 deraadt 130: .Pp
1.60 djm 131: .Nm
132: is also used to generate groups for use in Diffie-Hellman group
133: exchange (DH-GEX).
134: See the
135: .Sx MODULI GENERATION
136: section for details.
137: .Pp
1.2 deraadt 138: Normally each user wishing to use SSH
1.15 deraadt 139: with RSA or DSA authentication runs this once to create the authentication
1.1 deraadt 140: key in
1.68 djm 141: .Pa ~/.ssh/identity ,
142: .Pa ~/.ssh/id_dsa
1.15 deraadt 143: or
1.68 djm 144: .Pa ~/.ssh/id_rsa .
1.15 deraadt 145: Additionally, the system administrator may use this to generate host keys,
146: as seen in
147: .Pa /etc/rc .
1.2 deraadt 148: .Pp
1.1 deraadt 149: Normally this program generates the key and asks for a file in which
1.12 aaron 150: to store the private key.
151: The public key is stored in a file with the same name but
1.2 deraadt 152: .Dq .pub
1.12 aaron 153: appended.
154: The program also asks for a passphrase.
155: The passphrase may be empty to indicate no passphrase
1.26 markus 156: (host keys must have an empty passphrase), or it may be a string of
1.12 aaron 157: arbitrary length.
1.51 stevesk 158: A passphrase is similar to a password, except it can be a phrase with a
159: series of words, punctuation, numbers, whitespace, or any string of
160: characters you want.
161: Good passphrases are 10-30 characters long, are
1.1 deraadt 162: not simple sentences or otherwise easily guessable (English
1.42 markus 163: prose has only 1-2 bits of entropy per character, and provides very bad
1.51 stevesk 164: passphrases), and contain a mix of upper and lowercase letters,
165: numbers, and non-alphanumeric characters.
1.12 aaron 166: The passphrase can be changed later by using the
1.2 deraadt 167: .Fl p
1.1 deraadt 168: option.
1.2 deraadt 169: .Pp
1.12 aaron 170: There is no way to recover a lost passphrase.
171: If the passphrase is
1.49 deraadt 172: lost or forgotten, a new key must be generated and copied to the
1.1 deraadt 173: corresponding public key to other machines.
1.2 deraadt 174: .Pp
1.37 markus 175: For RSA1 keys,
176: there is also a comment field in the key file that is only for
1.12 aaron 177: convenience to the user to help identify the key.
178: The comment can tell what the key is for, or whatever is useful.
179: The comment is initialized to
1.2 deraadt 180: .Dq user@host
181: when the key is created, but can be changed using the
182: .Fl c
1.1 deraadt 183: option.
1.2 deraadt 184: .Pp
1.15 deraadt 185: After a key is generated, instructions below detail where the keys
186: should be placed to be activated.
187: .Pp
1.2 deraadt 188: The options are as follows:
189: .Bl -tag -width Ds
1.60 djm 190: .It Fl a Ar trials
191: Specifies the number of primality tests to perform when screening DH-GEX
192: candidates using the
193: .Fl T
194: command.
1.66 jmc 195: .It Fl B
196: Show the bubblebabble digest of specified private or public key file.
1.2 deraadt 197: .It Fl b Ar bits
1.12 aaron 198: Specifies the number of bits in the key to create.
1.72 dtucker 199: For RSA keys, the minimum size is 768 bits and the default is 2048 bits.
1.69 djm 200: Generally, 2048 bits is considered sufficient.
1.72 dtucker 201: DSA keys must be exactly 1024 bits as specified by FIPS 186-2.
1.66 jmc 202: .It Fl C Ar comment
203: Provides a new comment.
1.2 deraadt 204: .It Fl c
1.1 deraadt 205: Requests changing the comment in the private and public key files.
1.50 markus 206: This operation is only supported for RSA1 keys.
1.1 deraadt 207: The program will prompt for the file containing the private keys, for
1.41 stevesk 208: the passphrase if the key has one, and for the new comment.
1.81 markus 209: .It Fl D Ar pkcs11
1.83 markus 210: Download the RSA public keys provided by the PKCS#11 shared library
211: .Ar pkcs11 .
1.37 markus 212: .It Fl e
1.40 markus 213: This option will read a private or public OpenSSH key file and
1.73 markus 214: print the key in
215: RFC 4716 SSH Public Key File Format
1.37 markus 216: to stdout.
217: This option allows exporting keys for use by several commercial
218: SSH implementations.
1.66 jmc 219: .It Fl F Ar hostname
220: Search for the specified
221: .Ar hostname
222: in a
223: .Pa known_hosts
224: file, listing any occurrences found.
225: This option is useful to find hashed host names or addresses and may also be
226: used in conjunction with the
227: .Fl H
228: option to print found keys in a hashed format.
229: .It Fl f Ar filename
230: Specifies the filename of the key file.
231: .It Fl G Ar output_file
232: Generate candidate primes for DH-GEX.
233: These primes must be screened for
234: safety (using the
235: .Fl T
236: option) before use.
1.57 jakob 237: .It Fl g
1.62 jakob 238: Use generic DNS format when printing fingerprint resource records using the
1.63 jmc 239: .Fl r
1.62 jakob 240: command.
1.66 jmc 241: .It Fl H
242: Hash a
243: .Pa known_hosts
1.67 dtucker 244: file.
245: This replaces all hostnames and addresses with hashed representations
246: within the specified file; the original content is moved to a file with
247: a .old suffix.
1.66 jmc 248: These hashes may be used normally by
249: .Nm ssh
250: and
251: .Nm sshd ,
252: but they do not reveal identifying information should the file's contents
253: be disclosed.
254: This option will not modify existing hashed hostnames and is therefore safe
255: to use on files that mix hashed and non-hashed names.
1.84 ! djm 256: .It Fl h
! 257: When signing a key, create a host certificate instead of a user
! 258: certificate.
! 259: Please see the
! 260: .Sx CERTIFICATES
! 261: section for details.
! 262: .It Fl I
! 263: Specify the key identity when signing a public key.
! 264: Please see the
! 265: .Sx CERTIFICATES
! 266: section for details.
1.37 markus 267: .It Fl i
268: This option will read an unencrypted private (or public) key file
269: in SSH2-compatible format and print an OpenSSH compatible private
270: (or public) key to stdout.
271: .Nm
1.38 markus 272: also reads the
1.74 jmc 273: RFC 4716 SSH Public Key File Format.
1.37 markus 274: This option allows importing keys from several commercial
275: SSH implementations.
1.9 markus 276: .It Fl l
1.77 grunk 277: Show fingerprint of specified public key file.
1.50 markus 278: Private RSA1 keys are also supported.
279: For RSA and DSA keys
280: .Nm
1.78 jmc 281: tries to find the matching public key file and prints its fingerprint.
282: If combined with
283: .Fl v ,
284: an ASCII art representation of the key is supplied with the fingerprint.
1.66 jmc 285: .It Fl M Ar memory
286: Specify the amount of memory to use (in megabytes) when generating
287: candidate moduli for DH-GEX.
288: .It Fl N Ar new_passphrase
289: Provides the new passphrase.
1.84 ! djm 290: .It Fl n Ar principals
! 291: Specify one or more principals (user or host names) to be included in
! 292: a certificate when signing a key.
! 293: Multiple principals may be specified, separated by commas.
! 294: Please see the
! 295: .Sx CERTIFICATES
! 296: section for details.
! 297: .It Fl O Ar constraint
! 298: Specify a certificate constraint when signing a key.
! 299: This option may be specified multiple times.
! 300: Please see the
! 301: .Sx CERTIFICATES
! 302: section for details.
! 303: The constraints that are valid for user certificates are:
! 304: .Bl -tag -width Ds
! 305: .It Ic no-x11-forwarding
! 306: Disable X11 forwarding. (permitted by default)
! 307: .It Ic no-agent-forwarding
! 308: Disable
! 309: .Xr ssh-agent 1
! 310: forwarding. (permitted by default)
! 311: .It Ic no-port-forwarding
! 312: Disable port forwarding. (permitted by default)
! 313: .It Ic no-pty
! 314: Disable PTY allocation. (permitted by default)
! 315: .It Ic no-user-rc
! 316: Disable execution of
! 317: .Pa ~/.ssh/rc
! 318: by
! 319: .Xr sshd 8 .
! 320: (permitted by default)
! 321: .It Ic clear
! 322: Clear all enabled permissions.
! 323: This is useful for clearing the default set of permissions so permissions may
! 324: be added individually.
! 325: .It Ic permit-x11-forwarding
! 326: Allows X11 forwarding.
! 327: .It Ic permit-port-forwarding
! 328: Allows port forwarding.
! 329: .It Ic permit-pty
! 330: Allows PTY allocation.
! 331: .It Ic permit-user-rc
! 332: Allows execution of
! 333: .Pa ~/.ssh/rc
! 334: by
! 335: .Xr sshd 8 .
! 336: .It Ic force-command=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.
! 341: .It Ic source-address=address_list
! 342: Restrict the source addresses from which the certificate is considered valid
! 343: from.
! 344: The
! 345: .Ar address_list
! 346: is a comma-separated list of one or more address/netmask pairs in CIDR
! 347: format.
! 348: .El
! 349: .Pp
! 350: At present, no constraints are valid for host keys.
1.66 jmc 351: .It Fl P Ar passphrase
352: Provides the (old) passphrase.
1.2 deraadt 353: .It Fl p
1.1 deraadt 354: Requests changing the passphrase of a private key file instead of
1.12 aaron 355: creating a new private key.
356: The program will prompt for the file
1.1 deraadt 357: containing the private key, for the old passphrase, and twice for the
358: new passphrase.
1.5 aaron 359: .It Fl q
360: Silence
361: .Nm ssh-keygen .
362: Used by
363: .Pa /etc/rc
364: when creating a new key.
1.64 djm 365: .It Fl R Ar hostname
366: Removes all keys belonging to
367: .Ar hostname
1.65 jmc 368: from a
1.64 djm 369: .Pa known_hosts
370: file.
1.65 jmc 371: This option is useful to delete hashed hosts (see the
1.64 djm 372: .Fl H
373: option above).
1.66 jmc 374: .It Fl r Ar hostname
375: Print the SSHFP fingerprint resource record named
376: .Ar hostname
377: for the specified public key file.
1.60 djm 378: .It Fl S Ar start
379: Specify start point (in hex) when generating candidate moduli for DH-GEX.
1.84 ! djm 380: .It Fl s Ar ca_key
! 381: Certify (sign) a public key using the specified CA key.
! 382: Please see the
! 383: .Sx CERTIFICATES
! 384: section for details.
1.60 djm 385: .It Fl T Ar output_file
386: Test DH group exchange candidate primes (generated using the
387: .Fl G
388: option) for safety.
1.66 jmc 389: .It Fl t Ar type
390: Specifies the type of key to create.
391: The possible values are
392: .Dq rsa1
393: for protocol version 1 and
394: .Dq rsa
395: or
396: .Dq dsa
397: for protocol version 2.
1.84 ! djm 398: .It Fl V Ar validity_interval
! 399: Specify a validity interval when signing a certificate.
! 400: A validity interval may consist of a single time, indicating that the
! 401: certificate is valid beginning now and expiring at that time, or may consist
! 402: of two times separated by a colon to indicate an explicit time interval.
! 403: The start time may be specified as a date in YYYYMMDD format, a time
! 404: in YYYYMMDDHHMMSS format or a relative time (to the current time) consisting
! 405: of a minus sign followed by a relative time in the format described in the
! 406: .Sx TIME FORMATS
! 407: section of
! 408: .Xr ssh_config 5 .
! 409: The end time may be specified as a YYYYMMDD date, a YYYYMMDDHHMMSS time or
! 410: a relative time starting with a plus character.
! 411: .Pp
! 412: For example:
! 413: .Dq +52w1d
! 414: (valid from now to 52 weeks and one day from now),
! 415: .Dq -4w:+4w
! 416: (valid from four weeks ago to four weeks from now),
! 417: .Dq 20100101123000:20110101123000
! 418: (valid from 12:30 PM, January 1st, 2010 to 12:30 PM, January 1st, 2011),
! 419: .Dq -1d:20110101
! 420: (valid from yesterday to midnight, January 1st, 2011).
1.61 djm 421: .It Fl v
422: Verbose mode.
423: Causes
424: .Nm
425: to print debugging messages about its progress.
426: This is helpful for debugging moduli generation.
427: Multiple
428: .Fl v
429: options increase the verbosity.
430: The maximum is 3.
1.66 jmc 431: .It Fl W Ar generator
432: Specify desired generator when testing candidate moduli for DH-GEX.
433: .It Fl y
434: This option will read a private
435: OpenSSH format file and print an OpenSSH public key to stdout.
1.2 deraadt 436: .El
1.60 djm 437: .Sh MODULI GENERATION
438: .Nm
439: may be used to generate groups for the Diffie-Hellman Group Exchange
440: (DH-GEX) protocol.
441: Generating these groups is a two-step process: first, candidate
442: primes are generated using a fast, but memory intensive process.
443: These candidate primes are then tested for suitability (a CPU-intensive
444: process).
445: .Pp
446: Generation of primes is performed using the
447: .Fl G
448: option.
449: The desired length of the primes may be specified by the
450: .Fl b
451: option.
452: For example:
453: .Pp
1.66 jmc 454: .Dl # ssh-keygen -G moduli-2048.candidates -b 2048
1.60 djm 455: .Pp
456: By default, the search for primes begins at a random point in the
457: desired length range.
458: This may be overridden using the
459: .Fl S
460: option, which specifies a different start point (in hex).
461: .Pp
462: Once a set of candidates have been generated, they must be tested for
463: suitability.
464: This may be performed using the
465: .Fl T
466: option.
467: In this mode
468: .Nm
469: will read candidates from standard input (or a file specified using the
470: .Fl f
471: option).
472: For example:
473: .Pp
1.66 jmc 474: .Dl # ssh-keygen -T moduli-2048 -f moduli-2048.candidates
1.60 djm 475: .Pp
476: By default, each candidate will be subjected to 100 primality tests.
477: This may be overridden using the
478: .Fl a
479: option.
480: The DH generator value will be chosen automatically for the
481: prime under consideration.
482: If a specific generator is desired, it may be requested using the
483: .Fl W
484: option.
1.66 jmc 485: Valid generator values are 2, 3, and 5.
1.60 djm 486: .Pp
487: Screened DH groups may be installed in
488: .Pa /etc/moduli .
489: It is important that this file contains moduli of a range of bit lengths and
490: that both ends of a connection share common moduli.
1.84 ! djm 491: .Sh CERTIFICATES
! 492: .Nm
! 493: supports signing of keys to produce certificates that may be used for
! 494: user or host authentication.
! 495: Certificates consist of a public key, some identity information, zero or
! 496: more principal (user or host) names and an optional set of constraints that
! 497: are signed by a Certification Authority (CA) key.
! 498: Clients or servers may then trust only the CA key and verify its signature
! 499: on a certificate rather than trusting many user/host keys.
! 500: Note that OpenSSH certificates are a different, and much simpler, format to
! 501: the X.509 certificates used in
! 502: .Xr ssl 8 .
! 503: .Pp
! 504: .Nm
! 505: supports two types of certificates: user and host.
! 506: User certificates authenticate users to servers, whereas host certificates
! 507: authenticate server hosts to users. To generate a user certificate:
! 508: .Pp
! 509: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id /path/to/user_key.pub
! 510: .Pp
! 511: The resultant certificate will be placed in
! 512: .Pa /path/to/user_key_cert.pub .
! 513: A host certificate requires the
! 514: .Fl h
! 515: option:
! 516: .Pp
! 517: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id -h /path/to/host_key.pub
! 518: .Pp
! 519: The host certificate will be output to
! 520: .Pa /path/to/host_key_cert.pub .
! 521: In both cases,
! 522: .Ar key_id
! 523: is a "key identifier" that is logged by the server when the certificate
! 524: is used for authentication.
! 525: .Pp
! 526: Certificates may be limited to be valid for a set of principal (user/host)
! 527: names.
! 528: By default, generated certificates are valid for all users or hosts.
! 529: To generate a certificate for a specified set of principals:
! 530: .Pp
! 531: .Dl $ ssh-keygen -s ca_key -I key_id -n user1,user2 user_key.pub
! 532: .Dl $ ssh-keygen -s ca_key -I key_id -h -n host.domain user_key.pub
! 533: .Pp
! 534: Additional limitations on the validity and use of user certificates may
! 535: be specified through certificate constraints.
! 536: A constrained certificate may disable features of the SSH session, may be
! 537: valid only when presented from particular source addresses or may
! 538: force the use of a specific command.
! 539: For a list of valid certificate constraints, see the documentation for the
! 540: .Fl O
! 541: option above.
! 542: .Pp
! 543: Finally, certificates may be defined with a validity lifetime.
! 544: The
! 545: .Fl V
! 546: option allows specification of certificate start and end times.
! 547: A certificate that is presented at a time outside this range will not be
! 548: considered valid.
! 549: By default, certificates have a maximum validity interval.
! 550: .Pp
! 551: For certificates to be used for user or host authentication, the CA
! 552: public key must be trusted by
! 553: .Xr sshd 8
! 554: or
! 555: .Xr ssh 1 .
! 556: Please refer to those manual pages for details.
1.2 deraadt 557: .Sh FILES
558: .Bl -tag -width Ds
1.68 djm 559: .It Pa ~/.ssh/identity
1.36 itojun 560: Contains the protocol version 1 RSA authentication identity of the user.
1.12 aaron 561: This file should not be readable by anyone but the user.
562: It is possible to
1.1 deraadt 563: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 564: used to encrypt the private part of this file using 128-bit AES.
1.12 aaron 565: This file is not automatically accessed by
1.2 deraadt 566: .Nm
1.1 deraadt 567: but it is offered as the default file for the private key.
1.46 markus 568: .Xr ssh 1
1.15 deraadt 569: will read this file when a login attempt is made.
1.68 djm 570: .It Pa ~/.ssh/identity.pub
1.36 itojun 571: Contains the protocol version 1 RSA public key for authentication.
1.12 aaron 572: The contents of this file should be added to
1.68 djm 573: .Pa ~/.ssh/authorized_keys
1.2 deraadt 574: on all machines
1.49 deraadt 575: where the user wishes to log in using RSA authentication.
1.15 deraadt 576: There is no need to keep the contents of this file secret.
1.68 djm 577: .It Pa ~/.ssh/id_dsa
1.36 itojun 578: Contains the protocol version 2 DSA authentication identity of the user.
1.15 deraadt 579: This file should not be readable by anyone but the user.
580: It is possible to
581: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 582: used to encrypt the private part of this file using 128-bit AES.
1.15 deraadt 583: This file is not automatically accessed by
584: .Nm
585: but it is offered as the default file for the private key.
1.46 markus 586: .Xr ssh 1
1.15 deraadt 587: will read this file when a login attempt is made.
1.68 djm 588: .It Pa ~/.ssh/id_dsa.pub
1.36 itojun 589: Contains the protocol version 2 DSA public key for authentication.
590: The contents of this file should be added to
1.68 djm 591: .Pa ~/.ssh/authorized_keys
1.36 itojun 592: on all machines
1.49 deraadt 593: where the user wishes to log in using public key authentication.
1.36 itojun 594: There is no need to keep the contents of this file secret.
1.68 djm 595: .It Pa ~/.ssh/id_rsa
1.36 itojun 596: Contains the protocol version 2 RSA authentication identity of the user.
597: This file should not be readable by anyone but the user.
598: It is possible to
599: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 600: used to encrypt the private part of this file using 128-bit AES.
1.36 itojun 601: This file is not automatically accessed by
602: .Nm
603: but it is offered as the default file for the private key.
1.46 markus 604: .Xr ssh 1
1.36 itojun 605: will read this file when a login attempt is made.
1.68 djm 606: .It Pa ~/.ssh/id_rsa.pub
1.36 itojun 607: Contains the protocol version 2 RSA public key for authentication.
1.15 deraadt 608: The contents of this file should be added to
1.68 djm 609: .Pa ~/.ssh/authorized_keys
1.15 deraadt 610: on all machines
1.49 deraadt 611: where the user wishes to log in using public key authentication.
1.12 aaron 612: There is no need to keep the contents of this file secret.
1.60 djm 613: .It Pa /etc/moduli
614: Contains Diffie-Hellman groups used for DH-GEX.
615: The file format is described in
616: .Xr moduli 5 .
1.19 aaron 617: .El
1.2 deraadt 618: .Sh SEE ALSO
619: .Xr ssh 1 ,
620: .Xr ssh-add 1 ,
1.8 ericj 621: .Xr ssh-agent 1 ,
1.60 djm 622: .Xr moduli 5 ,
1.30 itojun 623: .Xr sshd 8
1.37 markus 624: .Rs
1.73 markus 625: .%R RFC 4716
626: .%T "The Secure Shell (SSH) Public Key File Format"
627: .%D 2006
1.37 markus 628: .Re
1.59 jmc 629: .Sh AUTHORS
630: OpenSSH is a derivative of the original and free
631: ssh 1.2.12 release by Tatu Ylonen.
632: Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
633: Theo de Raadt and Dug Song
634: removed many bugs, re-added newer features and
635: created OpenSSH.
636: Markus Friedl contributed the support for SSH
637: protocol versions 1.5 and 2.0.
![[BACK]](/icons/back.gif){kind=icon}
Return to ssh-keygen.1 CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh