Annotation of src/usr.bin/ssh/ssh-keygen.1, Revision 1.92
1.92 ! jmc 1: .\" $OpenBSD: ssh-keygen.1,v 1.91 2010/03/13 21:45:46 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: .\"
1.92 ! jmc 40: .Dd $Mdocdate: March 13 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
1.89 jmc 310: .It Ic clear
311: Clear all enabled permissions.
312: This is useful for clearing the default set of permissions so permissions may
313: be added individually.
314: .It Ic force-command Ns = Ns Ar command
315: Forces the execution of
316: .Ar command
317: instead of any shell or command specified by the user when
318: the certificate is used for authentication.
1.84 djm 319: .It Ic no-agent-forwarding
320: Disable
321: .Xr ssh-agent 1
1.85 jmc 322: forwarding (permitted by default).
1.84 djm 323: .It Ic no-port-forwarding
1.85 jmc 324: Disable port forwarding (permitted by default).
1.84 djm 325: .It Ic no-pty
1.85 jmc 326: Disable PTY allocation (permitted by default).
1.84 djm 327: .It Ic no-user-rc
328: Disable execution of
329: .Pa ~/.ssh/rc
330: by
1.85 jmc 331: .Xr sshd 8
332: (permitted by default).
1.89 jmc 333: .It Ic no-x11-forwarding
334: Disable X11 forwarding (permitted by default).
1.88 djm 335: .It Ic permit-agent-forwarding
336: Allows
337: .Xr ssh-agent 1
338: forwarding.
1.84 djm 339: .It Ic permit-port-forwarding
340: Allows port forwarding.
341: .It Ic permit-pty
342: Allows PTY allocation.
343: .It Ic permit-user-rc
344: Allows execution of
345: .Pa ~/.ssh/rc
346: by
347: .Xr sshd 8 .
1.89 jmc 348: .It Ic permit-x11-forwarding
349: Allows X11 forwarding.
350: .It Ic source-address Ns = Ns Ar address_list
1.90 jmc 351: Restrict the source addresses from which the certificate is considered valid.
1.84 djm 352: The
353: .Ar address_list
354: is a comma-separated list of one or more address/netmask pairs in CIDR
355: format.
356: .El
357: .Pp
358: At present, no constraints are valid for host keys.
1.66 jmc 359: .It Fl P Ar passphrase
360: Provides the (old) passphrase.
1.2 deraadt 361: .It Fl p
1.1 deraadt 362: Requests changing the passphrase of a private key file instead of
1.12 aaron 363: creating a new private key.
364: The program will prompt for the file
1.1 deraadt 365: containing the private key, for the old passphrase, and twice for the
366: new passphrase.
1.5 aaron 367: .It Fl q
368: Silence
369: .Nm ssh-keygen .
370: Used by
371: .Pa /etc/rc
372: when creating a new key.
1.64 djm 373: .It Fl R Ar hostname
374: Removes all keys belonging to
375: .Ar hostname
1.65 jmc 376: from a
1.64 djm 377: .Pa known_hosts
378: file.
1.65 jmc 379: This option is useful to delete hashed hosts (see the
1.64 djm 380: .Fl H
381: option above).
1.66 jmc 382: .It Fl r Ar hostname
383: Print the SSHFP fingerprint resource record named
384: .Ar hostname
385: for the specified public key file.
1.60 djm 386: .It Fl S Ar start
387: Specify start point (in hex) when generating candidate moduli for DH-GEX.
1.84 djm 388: .It Fl s Ar ca_key
389: Certify (sign) a public key using the specified CA key.
390: Please see the
391: .Sx CERTIFICATES
392: section for details.
1.60 djm 393: .It Fl T Ar output_file
394: Test DH group exchange candidate primes (generated using the
395: .Fl G
396: option) for safety.
1.66 jmc 397: .It Fl t Ar type
398: Specifies the type of key to create.
399: The possible values are
400: .Dq rsa1
401: for protocol version 1 and
402: .Dq rsa
403: or
404: .Dq dsa
405: for protocol version 2.
1.84 djm 406: .It Fl V Ar validity_interval
407: Specify a validity interval when signing a certificate.
408: A validity interval may consist of a single time, indicating that the
409: certificate is valid beginning now and expiring at that time, or may consist
410: of two times separated by a colon to indicate an explicit time interval.
411: The start time may be specified as a date in YYYYMMDD format, a time
412: in YYYYMMDDHHMMSS format or a relative time (to the current time) consisting
413: of a minus sign followed by a relative time in the format described in the
414: .Sx TIME FORMATS
415: section of
1.90 jmc 416: .Xr sshd_config 5 .
1.84 djm 417: The end time may be specified as a YYYYMMDD date, a YYYYMMDDHHMMSS time or
418: a relative time starting with a plus character.
419: .Pp
420: For example:
421: .Dq +52w1d
422: (valid from now to 52 weeks and one day from now),
423: .Dq -4w:+4w
424: (valid from four weeks ago to four weeks from now),
425: .Dq 20100101123000:20110101123000
426: (valid from 12:30 PM, January 1st, 2010 to 12:30 PM, January 1st, 2011),
427: .Dq -1d:20110101
428: (valid from yesterday to midnight, January 1st, 2011).
1.61 djm 429: .It Fl v
430: Verbose mode.
431: Causes
432: .Nm
433: to print debugging messages about its progress.
434: This is helpful for debugging moduli generation.
435: Multiple
436: .Fl v
437: options increase the verbosity.
438: The maximum is 3.
1.66 jmc 439: .It Fl W Ar generator
440: Specify desired generator when testing candidate moduli for DH-GEX.
441: .It Fl y
442: This option will read a private
443: OpenSSH format file and print an OpenSSH public key to stdout.
1.2 deraadt 444: .El
1.60 djm 445: .Sh MODULI GENERATION
446: .Nm
447: may be used to generate groups for the Diffie-Hellman Group Exchange
448: (DH-GEX) protocol.
449: Generating these groups is a two-step process: first, candidate
450: primes are generated using a fast, but memory intensive process.
451: These candidate primes are then tested for suitability (a CPU-intensive
452: process).
453: .Pp
454: Generation of primes is performed using the
455: .Fl G
456: option.
457: The desired length of the primes may be specified by the
458: .Fl b
459: option.
460: For example:
461: .Pp
1.66 jmc 462: .Dl # ssh-keygen -G moduli-2048.candidates -b 2048
1.60 djm 463: .Pp
464: By default, the search for primes begins at a random point in the
465: desired length range.
466: This may be overridden using the
467: .Fl S
468: option, which specifies a different start point (in hex).
469: .Pp
470: Once a set of candidates have been generated, they must be tested for
471: suitability.
472: This may be performed using the
473: .Fl T
474: option.
475: In this mode
476: .Nm
477: will read candidates from standard input (or a file specified using the
478: .Fl f
479: option).
480: For example:
481: .Pp
1.66 jmc 482: .Dl # ssh-keygen -T moduli-2048 -f moduli-2048.candidates
1.60 djm 483: .Pp
484: By default, each candidate will be subjected to 100 primality tests.
485: This may be overridden using the
486: .Fl a
487: option.
488: The DH generator value will be chosen automatically for the
489: prime under consideration.
490: If a specific generator is desired, it may be requested using the
491: .Fl W
492: option.
1.66 jmc 493: Valid generator values are 2, 3, and 5.
1.60 djm 494: .Pp
495: Screened DH groups may be installed in
496: .Pa /etc/moduli .
497: It is important that this file contains moduli of a range of bit lengths and
498: that both ends of a connection share common moduli.
1.84 djm 499: .Sh CERTIFICATES
500: .Nm
501: supports signing of keys to produce certificates that may be used for
502: user or host authentication.
503: Certificates consist of a public key, some identity information, zero or
504: more principal (user or host) names and an optional set of constraints that
505: are signed by a Certification Authority (CA) key.
506: Clients or servers may then trust only the CA key and verify its signature
507: on a certificate rather than trusting many user/host keys.
508: Note that OpenSSH certificates are a different, and much simpler, format to
509: the X.509 certificates used in
510: .Xr ssl 8 .
511: .Pp
512: .Nm
513: supports two types of certificates: user and host.
514: User certificates authenticate users to servers, whereas host certificates
1.85 jmc 515: authenticate server hosts to users.
516: To generate a user certificate:
1.84 djm 517: .Pp
518: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id /path/to/user_key.pub
519: .Pp
520: The resultant certificate will be placed in
1.91 djm 521: .Pa /path/to/user_key-cert.pub .
1.84 djm 522: A host certificate requires the
523: .Fl h
524: option:
525: .Pp
526: .Dl $ ssh-keygen -s /path/to/ca_key -I key_id -h /path/to/host_key.pub
527: .Pp
528: The host certificate will be output to
1.91 djm 529: .Pa /path/to/host_key-cert.pub .
1.84 djm 530: In both cases,
531: .Ar key_id
532: is a "key identifier" that is logged by the server when the certificate
533: is used for authentication.
534: .Pp
535: Certificates may be limited to be valid for a set of principal (user/host)
536: names.
537: By default, generated certificates are valid for all users or hosts.
538: To generate a certificate for a specified set of principals:
539: .Pp
540: .Dl $ ssh-keygen -s ca_key -I key_id -n user1,user2 user_key.pub
1.92 ! jmc 541: .Dl "$ ssh-keygen -s ca_key -I key_id -h -n host.domain user_key.pub"
1.84 djm 542: .Pp
543: Additional limitations on the validity and use of user certificates may
544: be specified through certificate constraints.
545: A constrained certificate may disable features of the SSH session, may be
546: valid only when presented from particular source addresses or may
547: force the use of a specific command.
548: For a list of valid certificate constraints, see the documentation for the
549: .Fl O
550: option above.
551: .Pp
552: Finally, certificates may be defined with a validity lifetime.
553: The
554: .Fl V
555: option allows specification of certificate start and end times.
556: A certificate that is presented at a time outside this range will not be
557: considered valid.
558: By default, certificates have a maximum validity interval.
559: .Pp
560: For certificates to be used for user or host authentication, the CA
561: public key must be trusted by
562: .Xr sshd 8
563: or
564: .Xr ssh 1 .
565: Please refer to those manual pages for details.
1.2 deraadt 566: .Sh FILES
567: .Bl -tag -width Ds
1.68 djm 568: .It Pa ~/.ssh/identity
1.36 itojun 569: Contains the protocol version 1 RSA authentication identity of the user.
1.12 aaron 570: This file should not be readable by anyone but the user.
571: It is possible to
1.1 deraadt 572: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 573: used to encrypt the private part of this file using 128-bit AES.
1.12 aaron 574: This file is not automatically accessed by
1.2 deraadt 575: .Nm
1.1 deraadt 576: but it is offered as the default file for the private key.
1.46 markus 577: .Xr ssh 1
1.15 deraadt 578: will read this file when a login attempt is made.
1.68 djm 579: .It Pa ~/.ssh/identity.pub
1.36 itojun 580: Contains the protocol version 1 RSA public key for authentication.
1.12 aaron 581: The contents of this file should be added to
1.68 djm 582: .Pa ~/.ssh/authorized_keys
1.2 deraadt 583: on all machines
1.49 deraadt 584: where the user wishes to log in using RSA authentication.
1.15 deraadt 585: There is no need to keep the contents of this file secret.
1.68 djm 586: .It Pa ~/.ssh/id_dsa
1.36 itojun 587: Contains the protocol version 2 DSA authentication identity of the user.
1.15 deraadt 588: This file should not be readable by anyone but the user.
589: It is possible to
590: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 591: used to encrypt the private part of this file using 128-bit AES.
1.15 deraadt 592: This file is not automatically accessed by
593: .Nm
594: but it is offered as the default file for the private key.
1.46 markus 595: .Xr ssh 1
1.15 deraadt 596: will read this file when a login attempt is made.
1.68 djm 597: .It Pa ~/.ssh/id_dsa.pub
1.36 itojun 598: Contains the protocol version 2 DSA public key for authentication.
599: The contents of this file should be added to
1.68 djm 600: .Pa ~/.ssh/authorized_keys
1.36 itojun 601: on all machines
1.49 deraadt 602: where the user wishes to log in using public key authentication.
1.36 itojun 603: There is no need to keep the contents of this file secret.
1.68 djm 604: .It Pa ~/.ssh/id_rsa
1.36 itojun 605: Contains the protocol version 2 RSA authentication identity of the user.
606: This file should not be readable by anyone but the user.
607: It is possible to
608: specify a passphrase when generating the key; that passphrase will be
1.80 dtucker 609: used to encrypt the private part of this file using 128-bit AES.
1.36 itojun 610: This file is not automatically accessed by
611: .Nm
612: but it is offered as the default file for the private key.
1.46 markus 613: .Xr ssh 1
1.36 itojun 614: will read this file when a login attempt is made.
1.68 djm 615: .It Pa ~/.ssh/id_rsa.pub
1.36 itojun 616: Contains the protocol version 2 RSA public key for authentication.
1.15 deraadt 617: The contents of this file should be added to
1.68 djm 618: .Pa ~/.ssh/authorized_keys
1.15 deraadt 619: on all machines
1.49 deraadt 620: where the user wishes to log in using public key authentication.
1.12 aaron 621: There is no need to keep the contents of this file secret.
1.60 djm 622: .It Pa /etc/moduli
623: Contains Diffie-Hellman groups used for DH-GEX.
624: The file format is described in
625: .Xr moduli 5 .
1.19 aaron 626: .El
1.2 deraadt 627: .Sh SEE ALSO
628: .Xr ssh 1 ,
629: .Xr ssh-add 1 ,
1.8 ericj 630: .Xr ssh-agent 1 ,
1.60 djm 631: .Xr moduli 5 ,
1.30 itojun 632: .Xr sshd 8
1.37 markus 633: .Rs
1.73 markus 634: .%R RFC 4716
635: .%T "The Secure Shell (SSH) Public Key File Format"
636: .%D 2006
1.37 markus 637: .Re
1.59 jmc 638: .Sh AUTHORS
639: OpenSSH is a derivative of the original and free
640: ssh 1.2.12 release by Tatu Ylonen.
641: Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
642: Theo de Raadt and Dug Song
643: removed many bugs, re-added newer features and
644: created OpenSSH.
645: Markus Friedl contributed the support for SSH
646: protocol versions 1.5 and 2.0.
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