Annotation of src/usr.bin/ssh/ssh-keygen.1, Revision 1.88
1.88 ! djm 1: .\" $OpenBSD: ssh-keygen.1,v 1.87 2010/03/04 22:52:40 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
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: .\"
1.87 jmc 40: .Dd $Mdocdate: March 4 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
1.2 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
1.20 markus 62: .Op Fl f Ar input_keyfile
1.16 deraadt 63: .Nm ssh-keygen
1.37 markus 64: .Fl e
1.20 markus 65: .Op Fl f Ar input_keyfile
1.16 deraadt 66: .Nm ssh-keygen
1.17 markus 67: .Fl y
1.20 markus 68: .Op Fl f Ar input_keyfile
1.17 markus 69: .Nm ssh-keygen
1.2 deraadt 70: .Fl c
71: .Op Fl P Ar passphrase
72: .Op Fl C Ar comment
1.9 markus 73: .Op Fl f Ar keyfile
74: .Nm ssh-keygen
75: .Fl l
1.35 markus 76: .Op Fl f Ar input_keyfile
77: .Nm ssh-keygen
78: .Fl B
1.20 markus 79: .Op Fl f Ar input_keyfile
1.48 jakob 80: .Nm ssh-keygen
1.82 jmc 81: .Fl D Ar pkcs11
1.48 jakob 82: .Nm ssh-keygen
1.64 djm 83: .Fl F Ar hostname
84: .Op Fl f Ar known_hosts_file
1.79 sthen 85: .Op Fl l
1.64 djm 86: .Nm ssh-keygen
87: .Fl H
88: .Op Fl f Ar known_hosts_file
89: .Nm ssh-keygen
90: .Fl R Ar hostname
91: .Op Fl f Ar known_hosts_file
1.57 jakob 92: .Nm ssh-keygen
93: .Fl r Ar hostname
94: .Op Fl f Ar input_keyfile
95: .Op Fl g
1.60 djm 96: .Nm ssh-keygen
97: .Fl G Ar output_file
1.61 djm 98: .Op Fl v
1.60 djm 99: .Op Fl b Ar bits
100: .Op Fl M Ar memory
101: .Op Fl S Ar start_point
102: .Nm ssh-keygen
103: .Fl T Ar output_file
104: .Fl f Ar input_file
1.61 djm 105: .Op Fl v
1.60 djm 106: .Op Fl a Ar num_trials
107: .Op Fl W Ar generator
1.84 djm 108: .Nm ssh-keygen
109: .Fl s Ar ca_key
110: .Fl I Ar certificate_identity
111: .Op Fl h
112: .Op Fl n Ar principals
113: .Op Fl O Ar constraint
114: .Op Fl V Ar validity_interval
115: .Ar
1.86 djm 116: .Nm ssh-keygen
117: .Fl L
118: .Op Fl f Ar input_keyfile
1.85 jmc 119: .Ek
1.13 aaron 120: .Sh DESCRIPTION
1.2 deraadt 121: .Nm
1.37 markus 122: generates, manages and converts authentication keys for
1.2 deraadt 123: .Xr ssh 1 .
1.15 deraadt 124: .Nm
1.54 deraadt 125: can create RSA keys for use by SSH protocol version 1 and RSA or DSA
1.58 jmc 126: keys for use by SSH protocol version 2.
127: The type of key to be generated is specified with the
1.25 markus 128: .Fl t
1.52 djm 129: option.
1.70 djm 130: If invoked without any arguments,
131: .Nm
1.71 jmc 132: will generate an RSA key for use in SSH protocol 2 connections.
1.15 deraadt 133: .Pp
1.60 djm 134: .Nm
135: is also used to generate groups for use in Diffie-Hellman group
136: exchange (DH-GEX).
137: See the
138: .Sx MODULI GENERATION
139: section for details.
140: .Pp
1.2 deraadt 141: Normally each user wishing to use SSH
1.15 deraadt 142: with RSA or DSA authentication runs this once to create the authentication
1.1 deraadt 143: key in
1.68 djm 144: .Pa ~/.ssh/identity ,
145: .Pa ~/.ssh/id_dsa
1.15 deraadt 146: or
1.68 djm 147: .Pa ~/.ssh/id_rsa .
1.15 deraadt 148: Additionally, the system administrator may use this to generate host keys,
149: as seen in
150: .Pa /etc/rc .
1.2 deraadt 151: .Pp
1.1 deraadt 152: Normally this program generates the key and asks for a file in which
1.12 aaron 153: to store the private key.
154: The public key is stored in a file with the same name but
1.2 deraadt 155: .Dq .pub
1.12 aaron 156: appended.
157: The program also asks for a passphrase.
158: The passphrase may be empty to indicate no passphrase
1.26 markus 159: (host keys must have an empty passphrase), or it may be a string of
1.12 aaron 160: arbitrary length.
1.51 stevesk 161: A passphrase is similar to a password, except it can be a phrase with a
162: series of words, punctuation, numbers, whitespace, or any string of
163: characters you want.
164: Good passphrases are 10-30 characters long, are
1.1 deraadt 165: not simple sentences or otherwise easily guessable (English
1.42 markus 166: prose has only 1-2 bits of entropy per character, and provides very bad
1.51 stevesk 167: passphrases), and contain a mix of upper and lowercase letters,
168: numbers, and non-alphanumeric characters.
1.12 aaron 169: The passphrase can be changed later by using the
1.2 deraadt 170: .Fl p
1.1 deraadt 171: option.
1.2 deraadt 172: .Pp
1.12 aaron 173: There is no way to recover a lost passphrase.
174: If the passphrase is
1.49 deraadt 175: lost or forgotten, a new key must be generated and copied to the
1.1 deraadt 176: corresponding public key to other machines.
1.2 deraadt 177: .Pp
1.37 markus 178: For RSA1 keys,
179: there is also a comment field in the key file that is only for
1.12 aaron 180: convenience to the user to help identify the key.
181: The comment can tell what the key is for, or whatever is useful.
182: The comment is initialized to
1.2 deraadt 183: .Dq user@host
184: when the key is created, but can be changed using the
185: .Fl c
1.1 deraadt 186: option.
1.2 deraadt 187: .Pp
1.15 deraadt 188: After a key is generated, instructions below detail where the keys
189: should be placed to be activated.
190: .Pp
1.2 deraadt 191: The options are as follows:
192: .Bl -tag -width Ds
1.60 djm 193: .It Fl a Ar trials
194: Specifies the number of primality tests to perform when screening DH-GEX
195: candidates using the
196: .Fl T
197: command.
1.66 jmc 198: .It Fl B
199: Show the bubblebabble digest of specified private or public key file.
1.2 deraadt 200: .It Fl b Ar bits
1.12 aaron 201: Specifies the number of bits in the key to create.
1.72 dtucker 202: For RSA keys, the minimum size is 768 bits and the default is 2048 bits.
1.69 djm 203: Generally, 2048 bits is considered sufficient.
1.72 dtucker 204: DSA keys must be exactly 1024 bits as specified by FIPS 186-2.
1.66 jmc 205: .It Fl C Ar comment
206: Provides a new comment.
1.2 deraadt 207: .It Fl c
1.1 deraadt 208: Requests changing the comment in the private and public key files.
1.50 markus 209: This operation is only supported for RSA1 keys.
1.1 deraadt 210: The program will prompt for the file containing the private keys, for
1.41 stevesk 211: the passphrase if the key has one, and for the new comment.
1.81 markus 212: .It Fl D Ar pkcs11
1.83 markus 213: Download the RSA public keys provided by the PKCS#11 shared library
214: .Ar pkcs11 .
1.37 markus 215: .It Fl e
1.40 markus 216: This option will read a private or public OpenSSH key file and
1.73 markus 217: print the key in
218: RFC 4716 SSH Public Key File Format
1.37 markus 219: to stdout.
220: This option allows exporting keys for use by several commercial
221: SSH implementations.
1.66 jmc 222: .It Fl F Ar hostname
223: Search for the specified
224: .Ar hostname
225: in a
226: .Pa known_hosts
227: file, listing any occurrences found.
228: This option is useful to find hashed host names or addresses and may also be
229: used in conjunction with the
230: .Fl H
231: option to print found keys in a hashed format.
232: .It Fl f Ar filename
233: Specifies the filename of the key file.
234: .It Fl G Ar output_file
235: Generate candidate primes for DH-GEX.
236: These primes must be screened for
237: safety (using the
238: .Fl T
239: option) before use.
1.57 jakob 240: .It Fl g
1.62 jakob 241: Use generic DNS format when printing fingerprint resource records using the
1.63 jmc 242: .Fl r
1.62 jakob 243: command.
1.66 jmc 244: .It Fl H
245: Hash a
246: .Pa known_hosts
1.67 dtucker 247: file.
248: This replaces all hostnames and addresses with hashed representations
249: within the specified file; the original content is moved to a file with
250: a .old suffix.
1.66 jmc 251: These hashes may be used normally by
252: .Nm ssh
253: and
254: .Nm sshd ,
255: but they do not reveal identifying information should the file's contents
256: be disclosed.
257: This option will not modify existing hashed hostnames and is therefore safe
258: to use on files that mix hashed and non-hashed names.
1.84 djm 259: .It Fl h
260: When signing a key, create a host certificate instead of a user
261: certificate.
262: Please see the
263: .Sx CERTIFICATES
264: section for details.
1.85 jmc 265: .It Fl I Ar certificate_identity
1.84 djm 266: Specify the key identity when signing a public key.
267: Please see the
268: .Sx CERTIFICATES
269: section for details.
1.37 markus 270: .It Fl i
271: This option will read an unencrypted private (or public) key file
272: in SSH2-compatible format and print an OpenSSH compatible private
273: (or public) key to stdout.
274: .Nm
1.38 markus 275: also reads the
1.74 jmc 276: RFC 4716 SSH Public Key File Format.
1.37 markus 277: This option allows importing keys from several commercial
278: SSH implementations.
1.86 djm 279: .It Fl L
280: Prints the contents of a certificate.
1.9 markus 281: .It Fl l
1.77 grunk 282: Show fingerprint of specified public key file.
1.50 markus 283: Private RSA1 keys are also supported.
284: For RSA and DSA keys
285: .Nm
1.78 jmc 286: tries to find the matching public key file and prints its fingerprint.
287: If combined with
288: .Fl v ,
289: an ASCII art representation of the key is supplied with the fingerprint.
1.66 jmc 290: .It Fl M Ar memory
291: Specify the amount of memory to use (in megabytes) when generating
292: candidate moduli for DH-GEX.
293: .It Fl N Ar new_passphrase
294: Provides the new passphrase.
1.84 djm 295: .It Fl n Ar principals
296: Specify one or more principals (user or host names) to be included in
297: a certificate when signing a key.
298: Multiple principals may be specified, separated by commas.
299: Please see the
300: .Sx CERTIFICATES
301: section for details.
302: .It Fl O Ar constraint
303: Specify a certificate constraint when signing a key.
304: This option may be specified multiple times.
305: Please see the
306: .Sx CERTIFICATES
307: section for details.
308: The constraints that are valid for user certificates are:
309: .Bl -tag -width Ds
310: .It Ic no-x11-forwarding
1.85 jmc 311: Disable X11 forwarding (permitted by default).
1.84 djm 312: .It Ic no-agent-forwarding
313: Disable
314: .Xr ssh-agent 1
1.85 jmc 315: forwarding (permitted by default).
1.84 djm 316: .It Ic no-port-forwarding
1.85 jmc 317: Disable port forwarding (permitted by default).
1.84 djm 318: .It Ic no-pty
1.85 jmc 319: Disable PTY allocation (permitted by default).
1.84 djm 320: .It Ic no-user-rc
321: Disable execution of
322: .Pa ~/.ssh/rc
323: by
1.85 jmc 324: .Xr sshd 8
325: (permitted by default).
1.84 djm 326: .It Ic clear
327: Clear all enabled permissions.
328: This is useful for clearing the default set of permissions so permissions may
329: be added individually.
330: .It Ic permit-x11-forwarding
331: Allows X11 forwarding.
1.88 ! djm 332: .It Ic permit-agent-forwarding
! 333: Allows
! 334: .Xr ssh-agent 1
! 335: forwarding.
1.84 djm 336: .It Ic permit-port-forwarding
337: Allows port forwarding.
338: .It Ic permit-pty
339: Allows PTY allocation.
340: .It Ic permit-user-rc
341: Allows execution of
342: .Pa ~/.ssh/rc
343: by
344: .Xr sshd 8 .
345: .It Ic force-command=command
346: Forces the execution of
347: .Ar command
348: instead of any shell or command specified by the user when
349: the certificate is used for authentication.
350: .It Ic source-address=address_list
351: Restrict the source addresses from which the certificate is considered valid
352: from.
353: The
354: .Ar address_list
355: is a comma-separated list of one or more address/netmask pairs in CIDR
356: format.
357: .El
358: .Pp
359: At present, no constraints are valid for host keys.
1.66 jmc 360: .It Fl P Ar passphrase
361: Provides the (old) passphrase.
1.2 deraadt 362: .It Fl p
1.1 deraadt 363: Requests changing the passphrase of a private key file instead of
1.12 aaron 364: creating a new private key.
365: The program will prompt for the file
1.1 deraadt 366: containing the private key, for the old passphrase, and twice for the
367: new passphrase.
1.5 aaron 368: .It Fl q
369: Silence
370: .Nm ssh-keygen .
371: Used by
372: .Pa /etc/rc
373: when creating a new key.
1.64 djm 374: .It Fl R Ar hostname
375: Removes all keys belonging to
376: .Ar hostname
1.65 jmc 377: from a
1.64 djm 378: .Pa known_hosts
379: file.
1.65 jmc 380: This option is useful to delete hashed hosts (see the
1.64 djm 381: .Fl H
382: option above).
1.66 jmc 383: .It Fl r Ar hostname
384: Print the SSHFP fingerprint resource record named
385: .Ar hostname
386: for the specified public key file.
1.60 djm 387: .It Fl S Ar start
388: Specify start point (in hex) when generating candidate moduli for DH-GEX.
1.84 djm 389: .It Fl s Ar ca_key
390: Certify (sign) a public key using the specified CA key.
391: Please see the
392: .Sx CERTIFICATES
393: section for details.
1.60 djm 394: .It Fl T Ar output_file
395: Test DH group exchange candidate primes (generated using the
396: .Fl G
397: option) for safety.
1.66 jmc 398: .It Fl t Ar type
399: Specifies the type of key to create.
400: The possible values are
401: .Dq rsa1
402: for protocol version 1 and
403: .Dq rsa
404: or
405: .Dq dsa
406: for protocol version 2.
1.84 djm 407: .It Fl V Ar validity_interval
408: Specify a validity interval when signing a certificate.
409: A validity interval may consist of a single time, indicating that the
410: certificate is valid beginning now and expiring at that time, or may consist
411: of two times separated by a colon to indicate an explicit time interval.
412: The start time may be specified as a date in YYYYMMDD format, a time
413: in YYYYMMDDHHMMSS format or a relative time (to the current time) consisting
414: of a minus sign followed by a relative time in the format described in the
415: .Sx TIME FORMATS
416: section of
417: .Xr ssh_config 5 .
418: The end time may be specified as a YYYYMMDD date, a YYYYMMDDHHMMSS time or
419: a relative time starting with a plus character.
420: .Pp
421: For example:
422: .Dq +52w1d
423: (valid from now to 52 weeks and one day from now),
424: .Dq -4w:+4w
425: (valid from four weeks ago to four weeks from now),
426: .Dq 20100101123000:20110101123000
427: (valid from 12:30 PM, January 1st, 2010 to 12:30 PM, January 1st, 2011),
428: .Dq -1d:20110101
429: (valid from yesterday to midnight, January 1st, 2011).
1.61 djm 430: .It Fl v
431: Verbose mode.
432: Causes
433: .Nm
434: to print debugging messages about its progress.
435: This is helpful for debugging moduli generation.
436: Multiple
437: .Fl v
438: options increase the verbosity.
439: The maximum is 3.
1.66 jmc 440: .It Fl W Ar generator
441: Specify desired generator when testing candidate moduli for DH-GEX.
442: .It Fl y
443: This option will read a private
444: OpenSSH format file and print an OpenSSH public key to stdout.
1.2 deraadt 445: .El
1.60 djm 446: .Sh MODULI GENERATION
447: .Nm
448: may be used to generate groups for the Diffie-Hellman Group Exchange
449: (DH-GEX) protocol.
450: Generating these groups is a two-step process: first, candidate
451: primes are generated using a fast, but memory intensive process.
452: These candidate primes are then tested for suitability (a CPU-intensive
453: process).
454: .Pp
455: Generation of primes is performed using the
456: .Fl G
457: option.
458: The desired length of the primes may be specified by the
459: .Fl b
460: option.
461: For example:
462: .Pp
1.66 jmc 463: .Dl # ssh-keygen -G moduli-2048.candidates -b 2048
1.60 djm 464: .Pp
465: By default, the search for primes begins at a random point in the
466: desired length range.
467: This may be overridden using the
468: .Fl S
469: option, which specifies a different start point (in hex).
470: .Pp
471: Once a set of candidates have been generated, they must be tested for
472: suitability.
473: This may be performed using the
474: .Fl T
475: option.
476: In this mode
477: .Nm
478: will read candidates from standard input (or a file specified using the
479: .Fl f
480: option).
481: For example:
482: .Pp
1.66 jmc 483: .Dl # ssh-keygen -T moduli-2048 -f moduli-2048.candidates
1.60 djm 484: .Pp
485: By default, each candidate will be subjected to 100 primality tests.
486: This may be overridden using the
487: .Fl a
488: option.
489: The DH generator value will be chosen automatically for the
490: prime under consideration.
491: If a specific generator is desired, it may be requested using the
492: .Fl W
493: option.
1.66 jmc 494: Valid generator values are 2, 3, and 5.
1.60 djm 495: .Pp
496: Screened DH groups may be installed in
497: .Pa /etc/moduli .
498: It is important that this file contains moduli of a range of bit lengths and
499: that both ends of a connection share common moduli.
1.84 djm 500: .Sh CERTIFICATES
501: .Nm
502: supports signing of keys to produce certificates that may be used for
503: user or host authentication.
504: Certificates consist of a public key, some identity information, zero or
505: more principal (user or host) names and an optional set of constraints that
506: are signed by a Certification Authority (CA) key.
507: Clients or servers may then trust only the CA key and verify its signature
508: on a certificate rather than trusting many user/host keys.
509: Note that OpenSSH certificates are a different, and much simpler, format to
510: the X.509 certificates used in
511: .Xr ssl 8 .
512: .Pp
513: .Nm
514: supports two types of certificates: user and host.
515: User certificates authenticate users to servers, whereas host certificates
1.85 jmc 516: authenticate server hosts to users.
517: To generate a user certificate:
1.84 djm 518: .Pp
519: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id /path/to/user_key.pub
520: .Pp
521: The resultant certificate will be placed in
522: .Pa /path/to/user_key_cert.pub .
523: A host certificate requires the
524: .Fl h
525: option:
526: .Pp
527: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id -h /path/to/host_key.pub
528: .Pp
529: The host certificate will be output to
530: .Pa /path/to/host_key_cert.pub .
531: In both cases,
532: .Ar key_id
533: is a "key identifier" that is logged by the server when the certificate
534: is used for authentication.
535: .Pp
536: Certificates may be limited to be valid for a set of principal (user/host)
537: names.
538: By default, generated certificates are valid for all users or hosts.
539: To generate a certificate for a specified set of principals:
540: .Pp
541: .Dl $ ssh-keygen -s ca_key -I key_id -n user1,user2 user_key.pub
542: .Dl $ ssh-keygen -s ca_key -I key_id -h -n host.domain user_key.pub
543: .Pp
544: Additional limitations on the validity and use of user certificates may
545: be specified through certificate constraints.
546: A constrained certificate may disable features of the SSH session, may be
547: valid only when presented from particular source addresses or may
548: force the use of a specific command.
549: For a list of valid certificate constraints, see the documentation for the
550: .Fl O
551: option above.
552: .Pp
553: Finally, certificates may be defined with a validity lifetime.
554: The
555: .Fl V
556: option allows specification of certificate start and end times.
557: A certificate that is presented at a time outside this range will not be
558: considered valid.
559: By default, certificates have a maximum validity interval.
560: .Pp
561: For certificates to be used for user or host authentication, the CA
562: public key must be trusted by
563: .Xr sshd 8
564: or
565: .Xr ssh 1 .
566: Please refer to those manual pages for details.
1.2 deraadt 567: .Sh FILES
568: .Bl -tag -width Ds
1.68 djm 569: .It Pa ~/.ssh/identity
1.36 itojun 570: Contains the protocol version 1 RSA authentication identity of the user.
1.12 aaron 571: This file should not be readable by anyone but the user.
572: It is possible to
1.1 deraadt 573: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 574: used to encrypt the private part of this file using 128-bit AES.
1.12 aaron 575: This file is not automatically accessed by
1.2 deraadt 576: .Nm
1.1 deraadt 577: but it is offered as the default file for the private key.
1.46 markus 578: .Xr ssh 1
1.15 deraadt 579: will read this file when a login attempt is made.
1.68 djm 580: .It Pa ~/.ssh/identity.pub
1.36 itojun 581: Contains the protocol version 1 RSA public key for authentication.
1.12 aaron 582: The contents of this file should be added to
1.68 djm 583: .Pa ~/.ssh/authorized_keys
1.2 deraadt 584: on all machines
1.49 deraadt 585: where the user wishes to log in using RSA authentication.
1.15 deraadt 586: There is no need to keep the contents of this file secret.
1.68 djm 587: .It Pa ~/.ssh/id_dsa
1.36 itojun 588: Contains the protocol version 2 DSA authentication identity of the user.
1.15 deraadt 589: This file should not be readable by anyone but the user.
590: It is possible to
591: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 592: used to encrypt the private part of this file using 128-bit AES.
1.15 deraadt 593: This file is not automatically accessed by
594: .Nm
595: but it is offered as the default file for the private key.
1.46 markus 596: .Xr ssh 1
1.15 deraadt 597: will read this file when a login attempt is made.
1.68 djm 598: .It Pa ~/.ssh/id_dsa.pub
1.36 itojun 599: Contains the protocol version 2 DSA public key for authentication.
600: The contents of this file should be added to
1.68 djm 601: .Pa ~/.ssh/authorized_keys
1.36 itojun 602: on all machines
1.49 deraadt 603: where the user wishes to log in using public key authentication.
1.36 itojun 604: There is no need to keep the contents of this file secret.
1.68 djm 605: .It Pa ~/.ssh/id_rsa
1.36 itojun 606: Contains the protocol version 2 RSA authentication identity of the user.
607: This file should not be readable by anyone but the user.
608: It is possible to
609: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 610: used to encrypt the private part of this file using 128-bit AES.
1.36 itojun 611: This file is not automatically accessed by
612: .Nm
613: but it is offered as the default file for the private key.
1.46 markus 614: .Xr ssh 1
1.36 itojun 615: will read this file when a login attempt is made.
1.68 djm 616: .It Pa ~/.ssh/id_rsa.pub
1.36 itojun 617: Contains the protocol version 2 RSA public key for authentication.
1.15 deraadt 618: The contents of this file should be added to
1.68 djm 619: .Pa ~/.ssh/authorized_keys
1.15 deraadt 620: on all machines
1.49 deraadt 621: where the user wishes to log in using public key authentication.
1.12 aaron 622: There is no need to keep the contents of this file secret.
1.60 djm 623: .It Pa /etc/moduli
624: Contains Diffie-Hellman groups used for DH-GEX.
625: The file format is described in
626: .Xr moduli 5 .
1.19 aaron 627: .El
1.2 deraadt 628: .Sh SEE ALSO
629: .Xr ssh 1 ,
630: .Xr ssh-add 1 ,
1.8 ericj 631: .Xr ssh-agent 1 ,
1.60 djm 632: .Xr moduli 5 ,
1.30 itojun 633: .Xr sshd 8
1.37 markus 634: .Rs
1.73 markus 635: .%R RFC 4716
636: .%T "The Secure Shell (SSH) Public Key File Format"
637: .%D 2006
1.37 markus 638: .Re
1.59 jmc 639: .Sh AUTHORS
640: OpenSSH is a derivative of the original and free
641: ssh 1.2.12 release by Tatu Ylonen.
642: Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
643: Theo de Raadt and Dug Song
644: removed many bugs, re-added newer features and
645: created OpenSSH.
646: Markus Friedl contributed the support for SSH
647: protocol versions 1.5 and 2.0.