Annotation of src/usr.bin/ssh/ssh-keygen.1, Revision 1.85
1.85 ! jmc 1: .\" $OpenBSD: ssh-keygen.1,v 1.84 2010/02/26 20:29:54 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: .\"
1.85 ! jmc 40: .Dd $Mdocdate: February 26 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
1.85 ! jmc 110: .Bk -words
1.84 djm 111: .Fl s Ar ca_key
112: .Fl I Ar certificate_identity
113: .Op Fl h
114: .Op Fl n Ar principals
115: .Op Fl O Ar constraint
116: .Op Fl V Ar validity_interval
117: .Ar
1.85 ! jmc 118: .Ek
1.13 aaron 119: .Sh DESCRIPTION
1.2 deraadt 120: .Nm
1.37 markus 121: generates, manages and converts authentication keys for
1.2 deraadt 122: .Xr ssh 1 .
1.15 deraadt 123: .Nm
1.54 deraadt 124: can create RSA keys for use by SSH protocol version 1 and RSA or DSA
1.58 jmc 125: keys for use by SSH protocol version 2.
126: The type of key to be generated is specified with the
1.25 markus 127: .Fl t
1.52 djm 128: option.
1.70 djm 129: If invoked without any arguments,
130: .Nm
1.71 jmc 131: will generate an RSA key for use in SSH protocol 2 connections.
1.15 deraadt 132: .Pp
1.60 djm 133: .Nm
134: is also used to generate groups for use in Diffie-Hellman group
135: exchange (DH-GEX).
136: See the
137: .Sx MODULI GENERATION
138: section for details.
139: .Pp
1.2 deraadt 140: Normally each user wishing to use SSH
1.15 deraadt 141: with RSA or DSA authentication runs this once to create the authentication
1.1 deraadt 142: key in
1.68 djm 143: .Pa ~/.ssh/identity ,
144: .Pa ~/.ssh/id_dsa
1.15 deraadt 145: or
1.68 djm 146: .Pa ~/.ssh/id_rsa .
1.15 deraadt 147: Additionally, the system administrator may use this to generate host keys,
148: as seen in
149: .Pa /etc/rc .
1.2 deraadt 150: .Pp
1.1 deraadt 151: Normally this program generates the key and asks for a file in which
1.12 aaron 152: to store the private key.
153: The public key is stored in a file with the same name but
1.2 deraadt 154: .Dq .pub
1.12 aaron 155: appended.
156: The program also asks for a passphrase.
157: The passphrase may be empty to indicate no passphrase
1.26 markus 158: (host keys must have an empty passphrase), or it may be a string of
1.12 aaron 159: arbitrary length.
1.51 stevesk 160: A passphrase is similar to a password, except it can be a phrase with a
161: series of words, punctuation, numbers, whitespace, or any string of
162: characters you want.
163: Good passphrases are 10-30 characters long, are
1.1 deraadt 164: not simple sentences or otherwise easily guessable (English
1.42 markus 165: prose has only 1-2 bits of entropy per character, and provides very bad
1.51 stevesk 166: passphrases), and contain a mix of upper and lowercase letters,
167: numbers, and non-alphanumeric characters.
1.12 aaron 168: The passphrase can be changed later by using the
1.2 deraadt 169: .Fl p
1.1 deraadt 170: option.
1.2 deraadt 171: .Pp
1.12 aaron 172: There is no way to recover a lost passphrase.
173: If the passphrase is
1.49 deraadt 174: lost or forgotten, a new key must be generated and copied to the
1.1 deraadt 175: corresponding public key to other machines.
1.2 deraadt 176: .Pp
1.37 markus 177: For RSA1 keys,
178: there is also a comment field in the key file that is only for
1.12 aaron 179: convenience to the user to help identify the key.
180: The comment can tell what the key is for, or whatever is useful.
181: The comment is initialized to
1.2 deraadt 182: .Dq user@host
183: when the key is created, but can be changed using the
184: .Fl c
1.1 deraadt 185: option.
1.2 deraadt 186: .Pp
1.15 deraadt 187: After a key is generated, instructions below detail where the keys
188: should be placed to be activated.
189: .Pp
1.2 deraadt 190: The options are as follows:
191: .Bl -tag -width Ds
1.60 djm 192: .It Fl a Ar trials
193: Specifies the number of primality tests to perform when screening DH-GEX
194: candidates using the
195: .Fl T
196: command.
1.66 jmc 197: .It Fl B
198: Show the bubblebabble digest of specified private or public key file.
1.2 deraadt 199: .It Fl b Ar bits
1.12 aaron 200: Specifies the number of bits in the key to create.
1.72 dtucker 201: For RSA keys, the minimum size is 768 bits and the default is 2048 bits.
1.69 djm 202: Generally, 2048 bits is considered sufficient.
1.72 dtucker 203: DSA keys must be exactly 1024 bits as specified by FIPS 186-2.
1.66 jmc 204: .It Fl C Ar comment
205: Provides a new comment.
1.2 deraadt 206: .It Fl c
1.1 deraadt 207: Requests changing the comment in the private and public key files.
1.50 markus 208: This operation is only supported for RSA1 keys.
1.1 deraadt 209: The program will prompt for the file containing the private keys, for
1.41 stevesk 210: the passphrase if the key has one, and for the new comment.
1.81 markus 211: .It Fl D Ar pkcs11
1.83 markus 212: Download the RSA public keys provided by the PKCS#11 shared library
213: .Ar pkcs11 .
1.37 markus 214: .It Fl e
1.40 markus 215: This option will read a private or public OpenSSH key file and
1.73 markus 216: print the key in
217: RFC 4716 SSH Public Key File Format
1.37 markus 218: to stdout.
219: This option allows exporting keys for use by several commercial
220: SSH implementations.
1.66 jmc 221: .It Fl F Ar hostname
222: Search for the specified
223: .Ar hostname
224: in a
225: .Pa known_hosts
226: file, listing any occurrences found.
227: This option is useful to find hashed host names or addresses and may also be
228: used in conjunction with the
229: .Fl H
230: option to print found keys in a hashed format.
231: .It Fl f Ar filename
232: Specifies the filename of the key file.
233: .It Fl G Ar output_file
234: Generate candidate primes for DH-GEX.
235: These primes must be screened for
236: safety (using the
237: .Fl T
238: option) before use.
1.57 jakob 239: .It Fl g
1.62 jakob 240: Use generic DNS format when printing fingerprint resource records using the
1.63 jmc 241: .Fl r
1.62 jakob 242: command.
1.66 jmc 243: .It Fl H
244: Hash a
245: .Pa known_hosts
1.67 dtucker 246: file.
247: This replaces all hostnames and addresses with hashed representations
248: within the specified file; the original content is moved to a file with
249: a .old suffix.
1.66 jmc 250: These hashes may be used normally by
251: .Nm ssh
252: and
253: .Nm sshd ,
254: but they do not reveal identifying information should the file's contents
255: be disclosed.
256: This option will not modify existing hashed hostnames and is therefore safe
257: to use on files that mix hashed and non-hashed names.
1.84 djm 258: .It Fl h
259: When signing a key, create a host certificate instead of a user
260: certificate.
261: Please see the
262: .Sx CERTIFICATES
263: section for details.
1.85 ! jmc 264: .It Fl I Ar certificate_identity
1.84 djm 265: Specify the key identity when signing a public key.
266: Please see the
267: .Sx CERTIFICATES
268: section for details.
1.37 markus 269: .It Fl i
270: This option will read an unencrypted private (or public) key file
271: in SSH2-compatible format and print an OpenSSH compatible private
272: (or public) key to stdout.
273: .Nm
1.38 markus 274: also reads the
1.74 jmc 275: RFC 4716 SSH Public Key File Format.
1.37 markus 276: This option allows importing keys from several commercial
277: SSH implementations.
1.9 markus 278: .It Fl l
1.77 grunk 279: Show fingerprint of specified public key file.
1.50 markus 280: Private RSA1 keys are also supported.
281: For RSA and DSA keys
282: .Nm
1.78 jmc 283: tries to find the matching public key file and prints its fingerprint.
284: If combined with
285: .Fl v ,
286: an ASCII art representation of the key is supplied with the fingerprint.
1.66 jmc 287: .It Fl M Ar memory
288: Specify the amount of memory to use (in megabytes) when generating
289: candidate moduli for DH-GEX.
290: .It Fl N Ar new_passphrase
291: Provides the new passphrase.
1.84 djm 292: .It Fl n Ar principals
293: Specify one or more principals (user or host names) to be included in
294: a certificate when signing a key.
295: Multiple principals may be specified, separated by commas.
296: Please see the
297: .Sx CERTIFICATES
298: section for details.
299: .It Fl O Ar constraint
300: Specify a certificate constraint when signing a key.
301: This option may be specified multiple times.
302: Please see the
303: .Sx CERTIFICATES
304: section for details.
305: The constraints that are valid for user certificates are:
306: .Bl -tag -width Ds
307: .It Ic no-x11-forwarding
1.85 ! jmc 308: Disable X11 forwarding (permitted by default).
1.84 djm 309: .It Ic no-agent-forwarding
310: Disable
311: .Xr ssh-agent 1
1.85 ! jmc 312: forwarding (permitted by default).
1.84 djm 313: .It Ic no-port-forwarding
1.85 ! jmc 314: Disable port forwarding (permitted by default).
1.84 djm 315: .It Ic no-pty
1.85 ! jmc 316: Disable PTY allocation (permitted by default).
1.84 djm 317: .It Ic no-user-rc
318: Disable execution of
319: .Pa ~/.ssh/rc
320: by
1.85 ! jmc 321: .Xr sshd 8
! 322: (permitted by default).
1.84 djm 323: .It Ic clear
324: Clear all enabled permissions.
325: This is useful for clearing the default set of permissions so permissions may
326: be added individually.
327: .It Ic permit-x11-forwarding
328: Allows X11 forwarding.
329: .It Ic permit-port-forwarding
330: Allows port forwarding.
331: .It Ic permit-pty
332: Allows PTY allocation.
333: .It Ic permit-user-rc
334: Allows execution of
335: .Pa ~/.ssh/rc
336: by
337: .Xr sshd 8 .
338: .It Ic force-command=command
339: Forces the execution of
340: .Ar command
341: instead of any shell or command specified by the user when
342: the certificate is used for authentication.
343: .It Ic source-address=address_list
344: Restrict the source addresses from which the certificate is considered valid
345: from.
346: The
347: .Ar address_list
348: is a comma-separated list of one or more address/netmask pairs in CIDR
349: format.
350: .El
351: .Pp
352: At present, no constraints are valid for host keys.
1.66 jmc 353: .It Fl P Ar passphrase
354: Provides the (old) passphrase.
1.2 deraadt 355: .It Fl p
1.1 deraadt 356: Requests changing the passphrase of a private key file instead of
1.12 aaron 357: creating a new private key.
358: The program will prompt for the file
1.1 deraadt 359: containing the private key, for the old passphrase, and twice for the
360: new passphrase.
1.5 aaron 361: .It Fl q
362: Silence
363: .Nm ssh-keygen .
364: Used by
365: .Pa /etc/rc
366: when creating a new key.
1.64 djm 367: .It Fl R Ar hostname
368: Removes all keys belonging to
369: .Ar hostname
1.65 jmc 370: from a
1.64 djm 371: .Pa known_hosts
372: file.
1.65 jmc 373: This option is useful to delete hashed hosts (see the
1.64 djm 374: .Fl H
375: option above).
1.66 jmc 376: .It Fl r Ar hostname
377: Print the SSHFP fingerprint resource record named
378: .Ar hostname
379: for the specified public key file.
1.60 djm 380: .It Fl S Ar start
381: Specify start point (in hex) when generating candidate moduli for DH-GEX.
1.84 djm 382: .It Fl s Ar ca_key
383: Certify (sign) a public key using the specified CA key.
384: Please see the
385: .Sx CERTIFICATES
386: section for details.
1.60 djm 387: .It Fl T Ar output_file
388: Test DH group exchange candidate primes (generated using the
389: .Fl G
390: option) for safety.
1.66 jmc 391: .It Fl t Ar type
392: Specifies the type of key to create.
393: The possible values are
394: .Dq rsa1
395: for protocol version 1 and
396: .Dq rsa
397: or
398: .Dq dsa
399: for protocol version 2.
1.84 djm 400: .It Fl V Ar validity_interval
401: Specify a validity interval when signing a certificate.
402: A validity interval may consist of a single time, indicating that the
403: certificate is valid beginning now and expiring at that time, or may consist
404: of two times separated by a colon to indicate an explicit time interval.
405: The start time may be specified as a date in YYYYMMDD format, a time
406: in YYYYMMDDHHMMSS format or a relative time (to the current time) consisting
407: of a minus sign followed by a relative time in the format described in the
408: .Sx TIME FORMATS
409: section of
410: .Xr ssh_config 5 .
411: The end time may be specified as a YYYYMMDD date, a YYYYMMDDHHMMSS time or
412: a relative time starting with a plus character.
413: .Pp
414: For example:
415: .Dq +52w1d
416: (valid from now to 52 weeks and one day from now),
417: .Dq -4w:+4w
418: (valid from four weeks ago to four weeks from now),
419: .Dq 20100101123000:20110101123000
420: (valid from 12:30 PM, January 1st, 2010 to 12:30 PM, January 1st, 2011),
421: .Dq -1d:20110101
422: (valid from yesterday to midnight, January 1st, 2011).
1.61 djm 423: .It Fl v
424: Verbose mode.
425: Causes
426: .Nm
427: to print debugging messages about its progress.
428: This is helpful for debugging moduli generation.
429: Multiple
430: .Fl v
431: options increase the verbosity.
432: The maximum is 3.
1.66 jmc 433: .It Fl W Ar generator
434: Specify desired generator when testing candidate moduli for DH-GEX.
435: .It Fl y
436: This option will read a private
437: OpenSSH format file and print an OpenSSH public key to stdout.
1.2 deraadt 438: .El
1.60 djm 439: .Sh MODULI GENERATION
440: .Nm
441: may be used to generate groups for the Diffie-Hellman Group Exchange
442: (DH-GEX) protocol.
443: Generating these groups is a two-step process: first, candidate
444: primes are generated using a fast, but memory intensive process.
445: These candidate primes are then tested for suitability (a CPU-intensive
446: process).
447: .Pp
448: Generation of primes is performed using the
449: .Fl G
450: option.
451: The desired length of the primes may be specified by the
452: .Fl b
453: option.
454: For example:
455: .Pp
1.66 jmc 456: .Dl # ssh-keygen -G moduli-2048.candidates -b 2048
1.60 djm 457: .Pp
458: By default, the search for primes begins at a random point in the
459: desired length range.
460: This may be overridden using the
461: .Fl S
462: option, which specifies a different start point (in hex).
463: .Pp
464: Once a set of candidates have been generated, they must be tested for
465: suitability.
466: This may be performed using the
467: .Fl T
468: option.
469: In this mode
470: .Nm
471: will read candidates from standard input (or a file specified using the
472: .Fl f
473: option).
474: For example:
475: .Pp
1.66 jmc 476: .Dl # ssh-keygen -T moduli-2048 -f moduli-2048.candidates
1.60 djm 477: .Pp
478: By default, each candidate will be subjected to 100 primality tests.
479: This may be overridden using the
480: .Fl a
481: option.
482: The DH generator value will be chosen automatically for the
483: prime under consideration.
484: If a specific generator is desired, it may be requested using the
485: .Fl W
486: option.
1.66 jmc 487: Valid generator values are 2, 3, and 5.
1.60 djm 488: .Pp
489: Screened DH groups may be installed in
490: .Pa /etc/moduli .
491: It is important that this file contains moduli of a range of bit lengths and
492: that both ends of a connection share common moduli.
1.84 djm 493: .Sh CERTIFICATES
494: .Nm
495: supports signing of keys to produce certificates that may be used for
496: user or host authentication.
497: Certificates consist of a public key, some identity information, zero or
498: more principal (user or host) names and an optional set of constraints that
499: are signed by a Certification Authority (CA) key.
500: Clients or servers may then trust only the CA key and verify its signature
501: on a certificate rather than trusting many user/host keys.
502: Note that OpenSSH certificates are a different, and much simpler, format to
503: the X.509 certificates used in
504: .Xr ssl 8 .
505: .Pp
506: .Nm
507: supports two types of certificates: user and host.
508: User certificates authenticate users to servers, whereas host certificates
1.85 ! jmc 509: authenticate server hosts to users.
! 510: To generate a user certificate:
1.84 djm 511: .Pp
512: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id /path/to/user_key.pub
513: .Pp
514: The resultant certificate will be placed in
515: .Pa /path/to/user_key_cert.pub .
516: A host certificate requires the
517: .Fl h
518: option:
519: .Pp
520: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id -h /path/to/host_key.pub
521: .Pp
522: The host certificate will be output to
523: .Pa /path/to/host_key_cert.pub .
524: In both cases,
525: .Ar key_id
526: is a "key identifier" that is logged by the server when the certificate
527: is used for authentication.
528: .Pp
529: Certificates may be limited to be valid for a set of principal (user/host)
530: names.
531: By default, generated certificates are valid for all users or hosts.
532: To generate a certificate for a specified set of principals:
533: .Pp
534: .Dl $ ssh-keygen -s ca_key -I key_id -n user1,user2 user_key.pub
535: .Dl $ ssh-keygen -s ca_key -I key_id -h -n host.domain user_key.pub
536: .Pp
537: Additional limitations on the validity and use of user certificates may
538: be specified through certificate constraints.
539: A constrained certificate may disable features of the SSH session, may be
540: valid only when presented from particular source addresses or may
541: force the use of a specific command.
542: For a list of valid certificate constraints, see the documentation for the
543: .Fl O
544: option above.
545: .Pp
546: Finally, certificates may be defined with a validity lifetime.
547: The
548: .Fl V
549: option allows specification of certificate start and end times.
550: A certificate that is presented at a time outside this range will not be
551: considered valid.
552: By default, certificates have a maximum validity interval.
553: .Pp
554: For certificates to be used for user or host authentication, the CA
555: public key must be trusted by
556: .Xr sshd 8
557: or
558: .Xr ssh 1 .
559: Please refer to those manual pages for details.
1.2 deraadt 560: .Sh FILES
561: .Bl -tag -width Ds
1.68 djm 562: .It Pa ~/.ssh/identity
1.36 itojun 563: Contains the protocol version 1 RSA authentication identity of the user.
1.12 aaron 564: This file should not be readable by anyone but the user.
565: It is possible to
1.1 deraadt 566: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 567: used to encrypt the private part of this file using 128-bit AES.
1.12 aaron 568: This file is not automatically accessed by
1.2 deraadt 569: .Nm
1.1 deraadt 570: but it is offered as the default file for the private key.
1.46 markus 571: .Xr ssh 1
1.15 deraadt 572: will read this file when a login attempt is made.
1.68 djm 573: .It Pa ~/.ssh/identity.pub
1.36 itojun 574: Contains the protocol version 1 RSA public key for authentication.
1.12 aaron 575: The contents of this file should be added to
1.68 djm 576: .Pa ~/.ssh/authorized_keys
1.2 deraadt 577: on all machines
1.49 deraadt 578: where the user wishes to log in using RSA authentication.
1.15 deraadt 579: There is no need to keep the contents of this file secret.
1.68 djm 580: .It Pa ~/.ssh/id_dsa
1.36 itojun 581: Contains the protocol version 2 DSA authentication identity of the user.
1.15 deraadt 582: This file should not be readable by anyone but the user.
583: It is possible to
584: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 585: used to encrypt the private part of this file using 128-bit AES.
1.15 deraadt 586: This file is not automatically accessed by
587: .Nm
588: but it is offered as the default file for the private key.
1.46 markus 589: .Xr ssh 1
1.15 deraadt 590: will read this file when a login attempt is made.
1.68 djm 591: .It Pa ~/.ssh/id_dsa.pub
1.36 itojun 592: Contains the protocol version 2 DSA public key for authentication.
593: The contents of this file should be added to
1.68 djm 594: .Pa ~/.ssh/authorized_keys
1.36 itojun 595: on all machines
1.49 deraadt 596: where the user wishes to log in using public key authentication.
1.36 itojun 597: There is no need to keep the contents of this file secret.
1.68 djm 598: .It Pa ~/.ssh/id_rsa
1.36 itojun 599: Contains the protocol version 2 RSA authentication identity of the user.
600: This file should not be readable by anyone but the user.
601: It is possible to
602: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 603: used to encrypt the private part of this file using 128-bit AES.
1.36 itojun 604: This file is not automatically accessed by
605: .Nm
606: but it is offered as the default file for the private key.
1.46 markus 607: .Xr ssh 1
1.36 itojun 608: will read this file when a login attempt is made.
1.68 djm 609: .It Pa ~/.ssh/id_rsa.pub
1.36 itojun 610: Contains the protocol version 2 RSA public key for authentication.
1.15 deraadt 611: The contents of this file should be added to
1.68 djm 612: .Pa ~/.ssh/authorized_keys
1.15 deraadt 613: on all machines
1.49 deraadt 614: where the user wishes to log in using public key authentication.
1.12 aaron 615: There is no need to keep the contents of this file secret.
1.60 djm 616: .It Pa /etc/moduli
617: Contains Diffie-Hellman groups used for DH-GEX.
618: The file format is described in
619: .Xr moduli 5 .
1.19 aaron 620: .El
1.2 deraadt 621: .Sh SEE ALSO
622: .Xr ssh 1 ,
623: .Xr ssh-add 1 ,
1.8 ericj 624: .Xr ssh-agent 1 ,
1.60 djm 625: .Xr moduli 5 ,
1.30 itojun 626: .Xr sshd 8
1.37 markus 627: .Rs
1.73 markus 628: .%R RFC 4716
629: .%T "The Secure Shell (SSH) Public Key File Format"
630: .%D 2006
1.37 markus 631: .Re
1.59 jmc 632: .Sh AUTHORS
633: OpenSSH is a derivative of the original and free
634: ssh 1.2.12 release by Tatu Ylonen.
635: Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
636: Theo de Raadt and Dug Song
637: removed many bugs, re-added newer features and
638: created OpenSSH.
639: Markus Friedl contributed the support for SSH
640: protocol versions 1.5 and 2.0.
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