Annotation of src/usr.bin/ssh/ssh-keygen.1, Revision 1.94
1.94 ! jmc 1: .\" $OpenBSD: ssh-keygen.1,v 1.93 2010/04/16 01:47:26 djm 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.
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1.1 deraadt 39: .\"
1.94 ! jmc 40: .Dd $Mdocdate: April 16 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
1.93 djm 113: .Op Fl O Ar option
1.84 djm 114: .Op Fl V Ar validity_interval
1.93 djm 115: .Op Fl z Ar serial_number
1.84 djm 116: .Ar
1.86 djm 117: .Nm ssh-keygen
118: .Fl L
119: .Op Fl f Ar input_keyfile
1.85 jmc 120: .Ek
1.13 aaron 121: .Sh DESCRIPTION
1.2 deraadt 122: .Nm
1.37 markus 123: generates, manages and converts authentication keys for
1.2 deraadt 124: .Xr ssh 1 .
1.15 deraadt 125: .Nm
1.54 deraadt 126: can create RSA keys for use by SSH protocol version 1 and RSA or DSA
1.58 jmc 127: keys for use by SSH protocol version 2.
128: The type of key to be generated is specified with the
1.25 markus 129: .Fl t
1.52 djm 130: option.
1.70 djm 131: If invoked without any arguments,
132: .Nm
1.71 jmc 133: will generate an RSA key for use in SSH protocol 2 connections.
1.15 deraadt 134: .Pp
1.60 djm 135: .Nm
136: is also used to generate groups for use in Diffie-Hellman group
137: exchange (DH-GEX).
138: See the
139: .Sx MODULI GENERATION
140: section for details.
141: .Pp
1.2 deraadt 142: Normally each user wishing to use SSH
1.15 deraadt 143: with RSA or DSA authentication runs this once to create the authentication
1.1 deraadt 144: key in
1.68 djm 145: .Pa ~/.ssh/identity ,
146: .Pa ~/.ssh/id_dsa
1.15 deraadt 147: or
1.68 djm 148: .Pa ~/.ssh/id_rsa .
1.15 deraadt 149: Additionally, the system administrator may use this to generate host keys,
150: as seen in
151: .Pa /etc/rc .
1.2 deraadt 152: .Pp
1.1 deraadt 153: Normally this program generates the key and asks for a file in which
1.12 aaron 154: to store the private key.
155: The public key is stored in a file with the same name but
1.2 deraadt 156: .Dq .pub
1.12 aaron 157: appended.
158: The program also asks for a passphrase.
159: The passphrase may be empty to indicate no passphrase
1.26 markus 160: (host keys must have an empty passphrase), or it may be a string of
1.12 aaron 161: arbitrary length.
1.51 stevesk 162: A passphrase is similar to a password, except it can be a phrase with a
163: series of words, punctuation, numbers, whitespace, or any string of
164: characters you want.
165: Good passphrases are 10-30 characters long, are
1.1 deraadt 166: not simple sentences or otherwise easily guessable (English
1.42 markus 167: prose has only 1-2 bits of entropy per character, and provides very bad
1.51 stevesk 168: passphrases), and contain a mix of upper and lowercase letters,
169: numbers, and non-alphanumeric characters.
1.12 aaron 170: The passphrase can be changed later by using the
1.2 deraadt 171: .Fl p
1.1 deraadt 172: option.
1.2 deraadt 173: .Pp
1.12 aaron 174: There is no way to recover a lost passphrase.
175: If the passphrase is
1.49 deraadt 176: lost or forgotten, a new key must be generated and copied to the
1.1 deraadt 177: corresponding public key to other machines.
1.2 deraadt 178: .Pp
1.37 markus 179: For RSA1 keys,
180: there is also a comment field in the key file that is only for
1.12 aaron 181: convenience to the user to help identify the key.
182: The comment can tell what the key is for, or whatever is useful.
183: The comment is initialized to
1.2 deraadt 184: .Dq user@host
185: when the key is created, but can be changed using the
186: .Fl c
1.1 deraadt 187: option.
1.2 deraadt 188: .Pp
1.15 deraadt 189: After a key is generated, instructions below detail where the keys
190: should be placed to be activated.
191: .Pp
1.2 deraadt 192: The options are as follows:
193: .Bl -tag -width Ds
1.60 djm 194: .It Fl a Ar trials
195: Specifies the number of primality tests to perform when screening DH-GEX
196: candidates using the
197: .Fl T
198: command.
1.66 jmc 199: .It Fl B
200: Show the bubblebabble digest of specified private or public key file.
1.2 deraadt 201: .It Fl b Ar bits
1.12 aaron 202: Specifies the number of bits in the key to create.
1.72 dtucker 203: For RSA keys, the minimum size is 768 bits and the default is 2048 bits.
1.69 djm 204: Generally, 2048 bits is considered sufficient.
1.72 dtucker 205: DSA keys must be exactly 1024 bits as specified by FIPS 186-2.
1.66 jmc 206: .It Fl C Ar comment
207: Provides a new comment.
1.2 deraadt 208: .It Fl c
1.1 deraadt 209: Requests changing the comment in the private and public key files.
1.50 markus 210: This operation is only supported for RSA1 keys.
1.1 deraadt 211: The program will prompt for the file containing the private keys, for
1.41 stevesk 212: the passphrase if the key has one, and for the new comment.
1.81 markus 213: .It Fl D Ar pkcs11
1.83 markus 214: Download the RSA public keys provided by the PKCS#11 shared library
215: .Ar pkcs11 .
1.37 markus 216: .It Fl e
1.40 markus 217: This option will read a private or public OpenSSH key file and
1.73 markus 218: print the key in
219: RFC 4716 SSH Public Key File Format
1.37 markus 220: to stdout.
221: This option allows exporting keys for use by several commercial
222: SSH implementations.
1.66 jmc 223: .It Fl F Ar hostname
224: Search for the specified
225: .Ar hostname
226: in a
227: .Pa known_hosts
228: file, listing any occurrences found.
229: This option is useful to find hashed host names or addresses and may also be
230: used in conjunction with the
231: .Fl H
232: option to print found keys in a hashed format.
233: .It Fl f Ar filename
234: Specifies the filename of the key file.
235: .It Fl G Ar output_file
236: Generate candidate primes for DH-GEX.
237: These primes must be screened for
238: safety (using the
239: .Fl T
240: option) before use.
1.57 jakob 241: .It Fl g
1.62 jakob 242: Use generic DNS format when printing fingerprint resource records using the
1.63 jmc 243: .Fl r
1.62 jakob 244: command.
1.66 jmc 245: .It Fl H
246: Hash a
247: .Pa known_hosts
1.67 dtucker 248: file.
249: This replaces all hostnames and addresses with hashed representations
250: within the specified file; the original content is moved to a file with
251: a .old suffix.
1.66 jmc 252: These hashes may be used normally by
253: .Nm ssh
254: and
255: .Nm sshd ,
256: but they do not reveal identifying information should the file's contents
257: be disclosed.
258: This option will not modify existing hashed hostnames and is therefore safe
259: to use on files that mix hashed and non-hashed names.
1.84 djm 260: .It Fl h
261: When signing a key, create a host certificate instead of a user
262: certificate.
263: Please see the
264: .Sx CERTIFICATES
265: section for details.
1.85 jmc 266: .It Fl I Ar certificate_identity
1.84 djm 267: Specify the key identity when signing a public key.
268: Please see the
269: .Sx CERTIFICATES
270: section for details.
1.37 markus 271: .It Fl i
272: This option will read an unencrypted private (or public) key file
273: in SSH2-compatible format and print an OpenSSH compatible private
274: (or public) key to stdout.
275: .Nm
1.38 markus 276: also reads the
1.74 jmc 277: RFC 4716 SSH Public Key File Format.
1.37 markus 278: This option allows importing keys from several commercial
279: SSH implementations.
1.86 djm 280: .It Fl L
281: Prints the contents of a certificate.
1.9 markus 282: .It Fl l
1.77 grunk 283: Show fingerprint of specified public key file.
1.50 markus 284: Private RSA1 keys are also supported.
285: For RSA and DSA keys
286: .Nm
1.78 jmc 287: tries to find the matching public key file and prints its fingerprint.
288: If combined with
289: .Fl v ,
290: an ASCII art representation of the key is supplied with the fingerprint.
1.66 jmc 291: .It Fl M Ar memory
292: Specify the amount of memory to use (in megabytes) when generating
293: candidate moduli for DH-GEX.
294: .It Fl N Ar new_passphrase
295: Provides the new passphrase.
1.84 djm 296: .It Fl n Ar principals
297: Specify one or more principals (user or host names) to be included in
298: a certificate when signing a key.
299: Multiple principals may be specified, separated by commas.
300: Please see the
301: .Sx CERTIFICATES
302: section for details.
1.93 djm 303: .It Fl O Ar option
304: Specify a certificate option when signing a key.
1.84 djm 305: This option may be specified multiple times.
306: Please see the
307: .Sx CERTIFICATES
308: section for details.
1.93 djm 309: The options that are valid for user certificates are:
1.84 djm 310: .Bl -tag -width Ds
1.89 jmc 311: .It Ic clear
312: Clear all enabled permissions.
313: This is useful for clearing the default set of permissions so permissions may
314: be added individually.
315: .It Ic force-command Ns = Ns Ar command
316: Forces the execution of
317: .Ar command
318: instead of any shell or command specified by the user when
319: the certificate is used for authentication.
1.84 djm 320: .It Ic no-agent-forwarding
321: Disable
322: .Xr ssh-agent 1
1.85 jmc 323: forwarding (permitted by default).
1.84 djm 324: .It Ic no-port-forwarding
1.85 jmc 325: Disable port forwarding (permitted by default).
1.84 djm 326: .It Ic no-pty
1.85 jmc 327: Disable PTY allocation (permitted by default).
1.84 djm 328: .It Ic no-user-rc
329: Disable execution of
330: .Pa ~/.ssh/rc
331: by
1.85 jmc 332: .Xr sshd 8
333: (permitted by default).
1.89 jmc 334: .It Ic no-x11-forwarding
335: Disable X11 forwarding (permitted by default).
1.88 djm 336: .It Ic permit-agent-forwarding
337: Allows
338: .Xr ssh-agent 1
339: forwarding.
1.84 djm 340: .It Ic permit-port-forwarding
341: Allows port forwarding.
342: .It Ic permit-pty
343: Allows PTY allocation.
344: .It Ic permit-user-rc
345: Allows execution of
346: .Pa ~/.ssh/rc
347: by
348: .Xr sshd 8 .
1.89 jmc 349: .It Ic permit-x11-forwarding
350: Allows X11 forwarding.
351: .It Ic source-address Ns = Ns Ar address_list
1.90 jmc 352: Restrict the source addresses from which the certificate is considered valid.
1.84 djm 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
1.93 djm 359: At present, no options 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
1.90 jmc 417: .Xr sshd_config 5 .
1.84 djm 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.
1.93 djm 445: .It Fl z Ar serial_number
446: Specifies a serial number to be embedded in the certificate to distinguish
447: this certificate from others from the same CA.
448: The default serial number is zero.
1.2 deraadt 449: .El
1.60 djm 450: .Sh MODULI GENERATION
451: .Nm
452: may be used to generate groups for the Diffie-Hellman Group Exchange
453: (DH-GEX) protocol.
454: Generating these groups is a two-step process: first, candidate
455: primes are generated using a fast, but memory intensive process.
456: These candidate primes are then tested for suitability (a CPU-intensive
457: process).
458: .Pp
459: Generation of primes is performed using the
460: .Fl G
461: option.
462: The desired length of the primes may be specified by the
463: .Fl b
464: option.
465: For example:
466: .Pp
1.66 jmc 467: .Dl # ssh-keygen -G moduli-2048.candidates -b 2048
1.60 djm 468: .Pp
469: By default, the search for primes begins at a random point in the
470: desired length range.
471: This may be overridden using the
472: .Fl S
473: option, which specifies a different start point (in hex).
474: .Pp
475: Once a set of candidates have been generated, they must be tested for
476: suitability.
477: This may be performed using the
478: .Fl T
479: option.
480: In this mode
481: .Nm
482: will read candidates from standard input (or a file specified using the
483: .Fl f
484: option).
485: For example:
486: .Pp
1.66 jmc 487: .Dl # ssh-keygen -T moduli-2048 -f moduli-2048.candidates
1.60 djm 488: .Pp
489: By default, each candidate will be subjected to 100 primality tests.
490: This may be overridden using the
491: .Fl a
492: option.
493: The DH generator value will be chosen automatically for the
494: prime under consideration.
495: If a specific generator is desired, it may be requested using the
496: .Fl W
497: option.
1.66 jmc 498: Valid generator values are 2, 3, and 5.
1.60 djm 499: .Pp
500: Screened DH groups may be installed in
501: .Pa /etc/moduli .
502: It is important that this file contains moduli of a range of bit lengths and
503: that both ends of a connection share common moduli.
1.84 djm 504: .Sh CERTIFICATES
505: .Nm
506: supports signing of keys to produce certificates that may be used for
507: user or host authentication.
508: Certificates consist of a public key, some identity information, zero or
1.94 ! jmc 509: more principal (user or host) names and a set of options that
1.84 djm 510: are signed by a Certification Authority (CA) key.
511: Clients or servers may then trust only the CA key and verify its signature
512: on a certificate rather than trusting many user/host keys.
513: Note that OpenSSH certificates are a different, and much simpler, format to
514: the X.509 certificates used in
515: .Xr ssl 8 .
516: .Pp
517: .Nm
518: supports two types of certificates: user and host.
519: User certificates authenticate users to servers, whereas host certificates
1.85 jmc 520: authenticate server hosts to users.
521: To generate a user certificate:
1.84 djm 522: .Pp
523: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id /path/to/user_key.pub
524: .Pp
525: The resultant certificate will be placed in
1.91 djm 526: .Pa /path/to/user_key-cert.pub .
1.84 djm 527: A host certificate requires the
528: .Fl h
529: option:
530: .Pp
531: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id -h /path/to/host_key.pub
532: .Pp
533: The host certificate will be output to
1.91 djm 534: .Pa /path/to/host_key-cert.pub .
1.84 djm 535: In both cases,
536: .Ar key_id
537: is a "key identifier" that is logged by the server when the certificate
538: is used for authentication.
539: .Pp
540: Certificates may be limited to be valid for a set of principal (user/host)
541: names.
542: By default, generated certificates are valid for all users or hosts.
543: To generate a certificate for a specified set of principals:
544: .Pp
545: .Dl $ ssh-keygen -s ca_key -I key_id -n user1,user2 user_key.pub
1.92 jmc 546: .Dl "$ ssh-keygen -s ca_key -I key_id -h -n host.domain user_key.pub"
1.84 djm 547: .Pp
548: Additional limitations on the validity and use of user certificates may
1.94 ! jmc 549: be specified through certificate options.
1.93 djm 550: A certificate option may disable features of the SSH session, may be
1.84 djm 551: valid only when presented from particular source addresses or may
552: force the use of a specific command.
1.93 djm 553: For a list of valid certificate options, see the documentation for the
1.84 djm 554: .Fl O
555: option above.
556: .Pp
557: Finally, certificates may be defined with a validity lifetime.
558: The
559: .Fl V
560: option allows specification of certificate start and end times.
561: A certificate that is presented at a time outside this range will not be
562: considered valid.
563: By default, certificates have a maximum validity interval.
564: .Pp
565: For certificates to be used for user or host authentication, the CA
566: public key must be trusted by
567: .Xr sshd 8
568: or
569: .Xr ssh 1 .
570: Please refer to those manual pages for details.
1.2 deraadt 571: .Sh FILES
572: .Bl -tag -width Ds
1.68 djm 573: .It Pa ~/.ssh/identity
1.36 itojun 574: Contains the protocol version 1 RSA authentication identity of the user.
1.12 aaron 575: This file should not be readable by anyone but the user.
576: It is possible to
1.1 deraadt 577: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 578: used to encrypt the private part of this file using 128-bit AES.
1.12 aaron 579: This file is not automatically accessed by
1.2 deraadt 580: .Nm
1.1 deraadt 581: but it is offered as the default file for the private key.
1.46 markus 582: .Xr ssh 1
1.15 deraadt 583: will read this file when a login attempt is made.
1.68 djm 584: .It Pa ~/.ssh/identity.pub
1.36 itojun 585: Contains the protocol version 1 RSA public key for authentication.
1.12 aaron 586: The contents of this file should be added to
1.68 djm 587: .Pa ~/.ssh/authorized_keys
1.2 deraadt 588: on all machines
1.49 deraadt 589: where the user wishes to log in using RSA authentication.
1.15 deraadt 590: There is no need to keep the contents of this file secret.
1.68 djm 591: .It Pa ~/.ssh/id_dsa
1.36 itojun 592: Contains the protocol version 2 DSA authentication identity of the user.
1.15 deraadt 593: This file should not be readable by anyone but the user.
594: It is possible to
595: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 596: used to encrypt the private part of this file using 128-bit AES.
1.15 deraadt 597: This file is not automatically accessed by
598: .Nm
599: but it is offered as the default file for the private key.
1.46 markus 600: .Xr ssh 1
1.15 deraadt 601: will read this file when a login attempt is made.
1.68 djm 602: .It Pa ~/.ssh/id_dsa.pub
1.36 itojun 603: Contains the protocol version 2 DSA public key for authentication.
604: The contents of this file should be added to
1.68 djm 605: .Pa ~/.ssh/authorized_keys
1.36 itojun 606: on all machines
1.49 deraadt 607: where the user wishes to log in using public key authentication.
1.36 itojun 608: There is no need to keep the contents of this file secret.
1.68 djm 609: .It Pa ~/.ssh/id_rsa
1.36 itojun 610: Contains the protocol version 2 RSA authentication identity of the user.
611: This file should not be readable by anyone but the user.
612: It is possible to
613: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 614: used to encrypt the private part of this file using 128-bit AES.
1.36 itojun 615: This file is not automatically accessed by
616: .Nm
617: but it is offered as the default file for the private key.
1.46 markus 618: .Xr ssh 1
1.36 itojun 619: will read this file when a login attempt is made.
1.68 djm 620: .It Pa ~/.ssh/id_rsa.pub
1.36 itojun 621: Contains the protocol version 2 RSA public key for authentication.
1.15 deraadt 622: The contents of this file should be added to
1.68 djm 623: .Pa ~/.ssh/authorized_keys
1.15 deraadt 624: on all machines
1.49 deraadt 625: where the user wishes to log in using public key authentication.
1.12 aaron 626: There is no need to keep the contents of this file secret.
1.60 djm 627: .It Pa /etc/moduli
628: Contains Diffie-Hellman groups used for DH-GEX.
629: The file format is described in
630: .Xr moduli 5 .
1.19 aaron 631: .El
1.2 deraadt 632: .Sh SEE ALSO
633: .Xr ssh 1 ,
634: .Xr ssh-add 1 ,
1.8 ericj 635: .Xr ssh-agent 1 ,
1.60 djm 636: .Xr moduli 5 ,
1.30 itojun 637: .Xr sshd 8
1.37 markus 638: .Rs
1.73 markus 639: .%R RFC 4716
640: .%T "The Secure Shell (SSH) Public Key File Format"
641: .%D 2006
1.37 markus 642: .Re
1.59 jmc 643: .Sh AUTHORS
644: OpenSSH is a derivative of the original and free
645: ssh 1.2.12 release by Tatu Ylonen.
646: Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
647: Theo de Raadt and Dug Song
648: removed many bugs, re-added newer features and
649: created OpenSSH.
650: Markus Friedl contributed the support for SSH
651: protocol versions 1.5 and 2.0.
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