diff options
author | Colin Watson <cjwatson@debian.org> | 2016-02-29 12:15:15 +0000 |
---|---|---|
committer | Colin Watson <cjwatson@debian.org> | 2016-02-29 12:15:15 +0000 |
commit | c52a95cc4754e6630c96fe65ae0c65eb41d2c590 (patch) | |
tree | 793395934013923b7b2426382c0676edcd4be3d4 /ssh.1 | |
parent | eeff4de96f5d7365750dc56912c2c62b5c28db6b (diff) | |
parent | 72b061d4ba0f909501c595d709ea76e06b01e5c9 (diff) |
Import openssh_7.2p1.orig.tar.gz
Diffstat (limited to 'ssh.1')
-rw-r--r-- | ssh.1 | 97 |
1 files changed, 42 insertions, 55 deletions
@@ -33,8 +33,8 @@ | |||
33 | .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | 33 | .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
34 | .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | 34 | .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
35 | .\" | 35 | .\" |
36 | .\" $OpenBSD: ssh.1,v 1.361 2015/07/20 18:44:12 millert Exp $ | 36 | .\" $OpenBSD: ssh.1,v 1.369 2016/02/17 07:38:19 jmc Exp $ |
37 | .Dd $Mdocdate: July 20 2015 $ | 37 | .Dd $Mdocdate: February 17 2016 $ |
38 | .Dt SSH 1 | 38 | .Dt SSH 1 |
39 | .Os | 39 | .Os |
40 | .Sh NAME | 40 | .Sh NAME |
@@ -58,7 +58,7 @@ | |||
58 | .Op Fl O Ar ctl_cmd | 58 | .Op Fl O Ar ctl_cmd |
59 | .Op Fl o Ar option | 59 | .Op Fl o Ar option |
60 | .Op Fl p Ar port | 60 | .Op Fl p Ar port |
61 | .Op Fl Q Cm cipher | cipher-auth | mac | kex | key | protocol-version | 61 | .Op Fl Q Ar query_option |
62 | .Op Fl R Ar address | 62 | .Op Fl R Ar address |
63 | .Op Fl S Ar ctl_path | 63 | .Op Fl S Ar ctl_path |
64 | .Op Fl W Ar host : Ns Ar port | 64 | .Op Fl W Ar host : Ns Ar port |
@@ -70,8 +70,7 @@ | |||
70 | .Nm | 70 | .Nm |
71 | (SSH client) is a program for logging into a remote machine and for | 71 | (SSH client) is a program for logging into a remote machine and for |
72 | executing commands on a remote machine. | 72 | executing commands on a remote machine. |
73 | It is intended to replace rlogin and rsh, | 73 | It is intended to provide secure encrypted communications between |
74 | and provide secure encrypted communications between | ||
75 | two untrusted hosts over an insecure network. | 74 | two untrusted hosts over an insecure network. |
76 | X11 connections, arbitrary TCP ports and | 75 | X11 connections, arbitrary TCP ports and |
77 | .Ux Ns -domain | 76 | .Ux Ns -domain |
@@ -85,7 +84,7 @@ connects and logs into the specified | |||
85 | name). | 84 | name). |
86 | The user must prove | 85 | The user must prove |
87 | his/her identity to the remote machine using one of several methods | 86 | his/her identity to the remote machine using one of several methods |
88 | depending on the protocol version used (see below). | 87 | (see below). |
89 | .Pp | 88 | .Pp |
90 | If | 89 | If |
91 | .Ar command | 90 | .Ar command |
@@ -304,6 +303,9 @@ It is possible to have multiple | |||
304 | .Fl i | 303 | .Fl i |
305 | options (and multiple identities specified in | 304 | options (and multiple identities specified in |
306 | configuration files). | 305 | configuration files). |
306 | If no certificates have been explicitly specified by the | ||
307 | .Cm CertificateFile | ||
308 | directive, | ||
307 | .Nm | 309 | .Nm |
308 | will also try to load certificate information from the filename obtained | 310 | will also try to load certificate information from the filename obtained |
309 | by appending | 311 | by appending |
@@ -400,17 +402,15 @@ in | |||
400 | for details. | 402 | for details. |
401 | .Pp | 403 | .Pp |
402 | .It Fl m Ar mac_spec | 404 | .It Fl m Ar mac_spec |
403 | Additionally, for protocol version 2 a comma-separated list of MAC | 405 | A comma-separated list of MAC (message authentication code) algorithms, |
404 | (message authentication code) algorithms can | 406 | specified in order of preference. |
405 | be specified in order of preference. | ||
406 | See the | 407 | See the |
407 | .Cm MACs | 408 | .Cm MACs |
408 | keyword for more information. | 409 | keyword for more information. |
409 | .Pp | 410 | .Pp |
410 | .It Fl N | 411 | .It Fl N |
411 | Do not execute a remote command. | 412 | Do not execute a remote command. |
412 | This is useful for just forwarding ports | 413 | This is useful for just forwarding ports. |
413 | (protocol version 2 only). | ||
414 | .Pp | 414 | .Pp |
415 | .It Fl n | 415 | .It Fl n |
416 | Redirects stdin from | 416 | Redirects stdin from |
@@ -460,6 +460,7 @@ For full details of the options listed below, and their possible values, see | |||
460 | .Xr ssh_config 5 . | 460 | .Xr ssh_config 5 . |
461 | .Pp | 461 | .Pp |
462 | .Bl -tag -width Ds -offset indent -compact | 462 | .Bl -tag -width Ds -offset indent -compact |
463 | .It AddKeysToAgent | ||
463 | .It AddressFamily | 464 | .It AddressFamily |
464 | .It BatchMode | 465 | .It BatchMode |
465 | .It BindAddress | 466 | .It BindAddress |
@@ -468,6 +469,7 @@ For full details of the options listed below, and their possible values, see | |||
468 | .It CanonicalizeHostname | 469 | .It CanonicalizeHostname |
469 | .It CanonicalizeMaxDots | 470 | .It CanonicalizeMaxDots |
470 | .It CanonicalizePermittedCNAMEs | 471 | .It CanonicalizePermittedCNAMEs |
472 | .It CertificateFile | ||
471 | .It ChallengeResponseAuthentication | 473 | .It ChallengeResponseAuthentication |
472 | .It CheckHostIP | 474 | .It CheckHostIP |
473 | .It Cipher | 475 | .It Cipher |
@@ -550,7 +552,7 @@ Port to connect to on the remote host. | |||
550 | This can be specified on a | 552 | This can be specified on a |
551 | per-host basis in the configuration file. | 553 | per-host basis in the configuration file. |
552 | .Pp | 554 | .Pp |
553 | .It Fl Q Cm cipher | cipher-auth | mac | kex | key | protocol-version | 555 | .It Fl Q Ar query_option |
554 | Queries | 556 | Queries |
555 | .Nm | 557 | .Nm |
556 | for the algorithms supported for the specified version 2. | 558 | for the algorithms supported for the specified version 2. |
@@ -564,7 +566,11 @@ The available features are: | |||
564 | .Ar kex | 566 | .Ar kex |
565 | (key exchange algorithms), | 567 | (key exchange algorithms), |
566 | .Ar key | 568 | .Ar key |
567 | (key types) and | 569 | (key types), |
570 | .Ar key-cert | ||
571 | (certificate key types), | ||
572 | .Ar key-plain | ||
573 | (non-certificate key types), and | ||
568 | .Ar protocol-version | 574 | .Ar protocol-version |
569 | (supported SSH protocol versions). | 575 | (supported SSH protocol versions). |
570 | .Pp | 576 | .Pp |
@@ -656,8 +662,8 @@ for details. | |||
656 | .Pp | 662 | .Pp |
657 | .It Fl s | 663 | .It Fl s |
658 | May be used to request invocation of a subsystem on the remote system. | 664 | May be used to request invocation of a subsystem on the remote system. |
659 | Subsystems are a feature of the SSH2 protocol which facilitate the use | 665 | Subsystems facilitate the use of SSH |
660 | of SSH as a secure transport for other applications (eg.\& | 666 | as a secure transport for other applications (e.g.\& |
661 | .Xr sftp 1 ) . | 667 | .Xr sftp 1 ) . |
662 | The subsystem is specified as the remote command. | 668 | The subsystem is specified as the remote command. |
663 | .Pp | 669 | .Pp |
@@ -702,7 +708,6 @@ Implies | |||
702 | .Cm ExitOnForwardFailure | 708 | .Cm ExitOnForwardFailure |
703 | and | 709 | and |
704 | .Cm ClearAllForwardings . | 710 | .Cm ClearAllForwardings . |
705 | Works with Protocol version 2 only. | ||
706 | .Pp | 711 | .Pp |
707 | .It Fl w Xo | 712 | .It Fl w Xo |
708 | .Ar local_tun Ns Op : Ns Ar remote_tun | 713 | .Ar local_tun Ns Op : Ns Ar remote_tun |
@@ -787,15 +792,10 @@ or the | |||
787 | and | 792 | and |
788 | .Fl 2 | 793 | .Fl 2 |
789 | options (see above). | 794 | options (see above). |
790 | Both protocols support similar authentication methods, | 795 | Protocol 1 should not be used |
791 | but protocol 2 is the default since | 796 | and is only offered to support legacy devices. |
792 | it provides additional mechanisms for confidentiality | 797 | It suffers from a number of cryptographic weaknesses |
793 | (the traffic is encrypted using AES, 3DES, Blowfish, CAST128, or Arcfour) | 798 | and doesn't support many of the advanced features available for protocol 2. |
794 | and integrity (hmac-md5, hmac-sha1, | ||
795 | hmac-sha2-256, hmac-sha2-512, | ||
796 | umac-64, umac-128, hmac-ripemd160). | ||
797 | Protocol 1 lacks a strong mechanism for ensuring the | ||
798 | integrity of the connection. | ||
799 | .Pp | 799 | .Pp |
800 | The methods available for authentication are: | 800 | The methods available for authentication are: |
801 | GSSAPI-based authentication, | 801 | GSSAPI-based authentication, |
@@ -804,8 +804,9 @@ public key authentication, | |||
804 | challenge-response authentication, | 804 | challenge-response authentication, |
805 | and password authentication. | 805 | and password authentication. |
806 | Authentication methods are tried in the order specified above, | 806 | Authentication methods are tried in the order specified above, |
807 | though protocol 2 has a configuration option to change the default order: | 807 | though |
808 | .Cm PreferredAuthentications . | 808 | .Cm PreferredAuthentications |
809 | can be used to change the default order. | ||
809 | .Pp | 810 | .Pp |
810 | Host-based authentication works as follows: | 811 | Host-based authentication works as follows: |
811 | If the machine the user logs in from is listed in | 812 | If the machine the user logs in from is listed in |
@@ -849,8 +850,6 @@ The server knows the public key, and only the user knows the private key. | |||
849 | .Nm | 850 | .Nm |
850 | implements public key authentication protocol automatically, | 851 | implements public key authentication protocol automatically, |
851 | using one of the DSA, ECDSA, Ed25519 or RSA algorithms. | 852 | using one of the DSA, ECDSA, Ed25519 or RSA algorithms. |
852 | Protocol 1 is restricted to using only RSA keys, | ||
853 | but protocol 2 may use any. | ||
854 | The HISTORY section of | 853 | The HISTORY section of |
855 | .Xr ssl 8 | 854 | .Xr ssl 8 |
856 | contains a brief discussion of the DSA and RSA algorithms. | 855 | contains a brief discussion of the DSA and RSA algorithms. |
@@ -872,26 +871,26 @@ This stores the private key in | |||
872 | .Pa ~/.ssh/identity | 871 | .Pa ~/.ssh/identity |
873 | (protocol 1), | 872 | (protocol 1), |
874 | .Pa ~/.ssh/id_dsa | 873 | .Pa ~/.ssh/id_dsa |
875 | (protocol 2 DSA), | 874 | (DSA), |
876 | .Pa ~/.ssh/id_ecdsa | 875 | .Pa ~/.ssh/id_ecdsa |
877 | (protocol 2 ECDSA), | 876 | (ECDSA), |
878 | .Pa ~/.ssh/id_ed25519 | 877 | .Pa ~/.ssh/id_ed25519 |
879 | (protocol 2 Ed25519), | 878 | (Ed25519), |
880 | or | 879 | or |
881 | .Pa ~/.ssh/id_rsa | 880 | .Pa ~/.ssh/id_rsa |
882 | (protocol 2 RSA) | 881 | (RSA) |
883 | and stores the public key in | 882 | and stores the public key in |
884 | .Pa ~/.ssh/identity.pub | 883 | .Pa ~/.ssh/identity.pub |
885 | (protocol 1), | 884 | (protocol 1), |
886 | .Pa ~/.ssh/id_dsa.pub | 885 | .Pa ~/.ssh/id_dsa.pub |
887 | (protocol 2 DSA), | 886 | (DSA), |
888 | .Pa ~/.ssh/id_ecdsa.pub | 887 | .Pa ~/.ssh/id_ecdsa.pub |
889 | (protocol 2 ECDSA), | 888 | (ECDSA), |
890 | .Pa ~/.ssh/id_ed25519.pub | 889 | .Pa ~/.ssh/id_ed25519.pub |
891 | (protocol 2 Ed25519), | 890 | (Ed25519), |
892 | or | 891 | or |
893 | .Pa ~/.ssh/id_rsa.pub | 892 | .Pa ~/.ssh/id_rsa.pub |
894 | (protocol 2 RSA) | 893 | (RSA) |
895 | in the user's home directory. | 894 | in the user's home directory. |
896 | The user should then copy the public key | 895 | The user should then copy the public key |
897 | to | 896 | to |
@@ -919,14 +918,16 @@ The most convenient way to use public key or certificate authentication | |||
919 | may be with an authentication agent. | 918 | may be with an authentication agent. |
920 | See | 919 | See |
921 | .Xr ssh-agent 1 | 920 | .Xr ssh-agent 1 |
921 | and (optionally) the | ||
922 | .Cm AddKeysToAgent | ||
923 | directive in | ||
924 | .Xr ssh_config 5 | ||
922 | for more information. | 925 | for more information. |
923 | .Pp | 926 | .Pp |
924 | Challenge-response authentication works as follows: | 927 | Challenge-response authentication works as follows: |
925 | The server sends an arbitrary | 928 | The server sends an arbitrary |
926 | .Qq challenge | 929 | .Qq challenge |
927 | text, and prompts for a response. | 930 | text, and prompts for a response. |
928 | Protocol 2 allows multiple challenges and responses; | ||
929 | protocol 1 is restricted to just one challenge/response. | ||
930 | Examples of challenge-response authentication include | 931 | Examples of challenge-response authentication include |
931 | .Bx | 932 | .Bx |
932 | Authentication (see | 933 | Authentication (see |
@@ -1025,7 +1026,7 @@ at logout when waiting for forwarded connection / X11 sessions to terminate. | |||
1025 | Display a list of escape characters. | 1026 | Display a list of escape characters. |
1026 | .It Cm ~B | 1027 | .It Cm ~B |
1027 | Send a BREAK to the remote system | 1028 | Send a BREAK to the remote system |
1028 | (only useful for SSH protocol version 2 and if the peer supports it). | 1029 | (only useful if the peer supports it). |
1029 | .It Cm ~C | 1030 | .It Cm ~C |
1030 | Open command line. | 1031 | Open command line. |
1031 | Currently this allows the addition of port forwardings using the | 1032 | Currently this allows the addition of port forwardings using the |
@@ -1058,7 +1059,7 @@ Basic help is available, using the | |||
1058 | option. | 1059 | option. |
1059 | .It Cm ~R | 1060 | .It Cm ~R |
1060 | Request rekeying of the connection | 1061 | Request rekeying of the connection |
1061 | (only useful for SSH protocol version 2 and if the peer supports it). | 1062 | (only useful if the peer supports it). |
1062 | .It Cm ~V | 1063 | .It Cm ~V |
1063 | Decrease the verbosity | 1064 | Decrease the verbosity |
1064 | .Pq Ic LogLevel | 1065 | .Pq Ic LogLevel |
@@ -1526,20 +1527,6 @@ The file format and configuration options are described in | |||
1526 | .It Pa /etc/ssh/ssh_host_rsa_key | 1527 | .It Pa /etc/ssh/ssh_host_rsa_key |
1527 | These files contain the private parts of the host keys | 1528 | These files contain the private parts of the host keys |
1528 | and are used for host-based authentication. | 1529 | and are used for host-based authentication. |
1529 | If protocol version 1 is used, | ||
1530 | .Nm | ||
1531 | must be setuid root, since the host key is readable only by root. | ||
1532 | For protocol version 2, | ||
1533 | .Nm | ||
1534 | uses | ||
1535 | .Xr ssh-keysign 8 | ||
1536 | to access the host keys, | ||
1537 | eliminating the requirement that | ||
1538 | .Nm | ||
1539 | be setuid root when host-based authentication is used. | ||
1540 | By default | ||
1541 | .Nm | ||
1542 | is not setuid root. | ||
1543 | .Pp | 1530 | .Pp |
1544 | .It Pa /etc/ssh/ssh_known_hosts | 1531 | .It Pa /etc/ssh/ssh_known_hosts |
1545 | Systemwide list of known host keys. | 1532 | Systemwide list of known host keys. |