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authorColin Watson <cjwatson@debian.org>2020-02-21 11:57:14 +0000
committerColin Watson <cjwatson@debian.org>2020-02-21 11:57:14 +0000
commitf0de78bd4f29fa688c5df116f3f9cd43543a76d0 (patch)
tree856b0dee3f2764c13a32dad5ffe2424fab7fef41 /ssh-agent.0
parent4213eec74e74de6310c27a40c3e9759a08a73996 (diff)
parent8aa3455b16fddea4c0144a7c4a1edb10ec67dcc8 (diff)
Import openssh_8.2p1.orig.tar.gz
Diffstat (limited to 'ssh-agent.0')
-rw-r--r--ssh-agent.099
1 files changed, 48 insertions, 51 deletions
diff --git a/ssh-agent.0 b/ssh-agent.0
index 1ef2702f6..c5fe8b153 100644
--- a/ssh-agent.0
+++ b/ssh-agent.0
@@ -1,27 +1,18 @@
1SSH-AGENT(1) General Commands Manual SSH-AGENT(1) 1SSH-AGENT(1) General Commands Manual SSH-AGENT(1)
2 2
3NAME 3NAME
4 ssh-agent M-bM-^@M-^S authentication agent 4 ssh-agent M-bM-^@M-^S OpenSSH authentication agent
5 5
6SYNOPSIS 6SYNOPSIS
7 ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash] 7 ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]
8 [-P pkcs11_whitelist] [-t life] [command [arg ...]] 8 [-P provider_whitelist] [-t life] [command [arg ...]]
9 ssh-agent [-c | -s] -k 9 ssh-agent [-c | -s] -k
10 10
11DESCRIPTION 11DESCRIPTION
12 ssh-agent is a program to hold private keys used for public key 12 ssh-agent is a program to hold private keys used for public key
13 authentication (RSA, DSA, ECDSA, Ed25519). ssh-agent is usually started 13 authentication. Through use of environment variables the agent can be
14 in the beginning of an X-session or a login session, and all other 14 located and automatically used for authentication when logging in to
15 windows or programs are started as clients to the ssh-agent program. 15 other machines using ssh(1).
16 Through use of environment variables the agent can be located and
17 automatically used for authentication when logging in to other machines
18 using ssh(1).
19
20 The agent initially does not have any private keys. Keys are added using
21 ssh(1) (see AddKeysToAgent in ssh_config(5) for details) or ssh-add(1).
22 Multiple identities may be stored in ssh-agent concurrently and ssh(1)
23 will automatically use them if present. ssh-add(1) is also used to
24 remove keys from ssh-agent and to query the keys that are held in one.
25 16
26 The options are as follows: 17 The options are as follows:
27 18
@@ -46,13 +37,13 @@ DESCRIPTION
46 -k Kill the current agent (given by the SSH_AGENT_PID environment 37 -k Kill the current agent (given by the SSH_AGENT_PID environment
47 variable). 38 variable).
48 39
49 -P pkcs11_whitelist 40 -P provider_whitelist
50 Specify a pattern-list of acceptable paths for PKCS#11 shared 41 Specify a pattern-list of acceptable paths for PKCS#11 and FIDO
51 libraries that may be added using the -s option to ssh-add(1). 42 authenticator shared libraries that may be used with the -S or -s
52 The default is to allow loading PKCS#11 libraries from 43 options to ssh-add(1). Libraries that do not match the whitelist
53 M-bM-^@M-^\/usr/lib/*,/usr/local/lib/*M-bM-^@M-^]. PKCS#11 libraries that do not 44 will be refused. See PATTERNS in ssh_config(5) for a description
54 match the whitelist will be refused. See PATTERNS in 45 of pattern-list syntax. The default whitelist is
55 ssh_config(5) for a description of pattern-list syntax. 46 M-bM-^@M-^\/usr/lib/*,/usr/local/lib/*M-bM-^@M-^].
56 47
57 -s Generate Bourne shell commands on stdout. This is the default if 48 -s Generate Bourne shell commands on stdout. This is the default if
58 SHELL does not look like it's a csh style of shell. 49 SHELL does not look like it's a csh style of shell.
@@ -64,41 +55,47 @@ DESCRIPTION
64 for an identity with ssh-add(1) overrides this value. Without 55 for an identity with ssh-add(1) overrides this value. Without
65 this option the default maximum lifetime is forever. 56 this option the default maximum lifetime is forever.
66 57
67 If a command line is given, this is executed as a subprocess of the 58 command [arg ...]
68 agent. When the command dies, so does the agent. 59 If a command (and optional arguments) is given, this is executed
60 as a subprocess of the agent. The agent exits automatically when
61 the command given on the command line terminates.
69 62
70 The idea is that the agent is run in the user's local PC, laptop, or 63 There are two main ways to get an agent set up. The first is at the
71 terminal. Authentication data need not be stored on any other machine, 64 start of an X session, where all other windows or programs are started as
72 and authentication passphrases never go over the network. However, the 65 children of the ssh-agent program. The agent starts a command under
73 connection to the agent is forwarded over SSH remote logins, and the user 66 which its environment variables are exported, for example ssh-agent xterm
74 can thus use the privileges given by the identities anywhere in the 67 &. When the command terminates, so does the agent.
75 network in a secure way.
76 68
77 There are two main ways to get an agent set up: The first is that the 69 The second method is used for a login session. When ssh-agent is
78 agent starts a new subcommand into which some environment variables are 70 started, it prints the shell commands required to set its environment
79 exported, eg ssh-agent xterm &. The second is that the agent prints the 71 variables, which in turn can be evaluated in the calling shell, for
80 needed shell commands (either sh(1) or csh(1) syntax can be generated) 72 example eval `ssh-agent -s`.
81 which can be evaluated in the calling shell, eg eval `ssh-agent -s` for
82 Bourne-type shells such as sh(1) or ksh(1) and eval `ssh-agent -c` for
83 csh(1) and derivatives.
84 73
85 Later ssh(1) looks at these variables and uses them to establish a 74 In both cases, ssh(1) looks at these environment variables and uses them
86 connection to the agent. 75 to establish a connection to the agent.
87 76
88 The agent will never send a private key over its request channel. 77 The agent initially does not have any private keys. Keys are added using
89 Instead, operations that require a private key will be performed by the 78 ssh-add(1) or by ssh(1) when AddKeysToAgent is set in ssh_config(5).
90 agent, and the result will be returned to the requester. This way, 79 Multiple identities may be stored in ssh-agent concurrently and ssh(1)
91 private keys are not exposed to clients using the agent. 80 will automatically use them if present. ssh-add(1) is also used to
81 remove keys from ssh-agent and to query the keys that are held in one.
92 82
93 A UNIX-domain socket is created and the name of this socket is stored in 83 Connections to ssh-agent may be forwarded from further remote hosts using
94 the SSH_AUTH_SOCK environment variable. The socket is made accessible 84 the -A option to ssh(1) (but see the caveats documented therein),
95 only to the current user. This method is easily abused by root or 85 avoiding the need for authentication data to be stored on other machines.
96 another instance of the same user. 86 Authentication passphrases and private keys never go over the network:
87 the connection to the agent is forwarded over SSH remote connections and
88 the result is returned to the requester, allowing the user access to
89 their identities anywhere in the network in a secure fashion.
97 90
98 The SSH_AGENT_PID environment variable holds the agent's process ID. 91ENVIRONMENT
92 SSH_AGENT_PID When ssh-agent starts, it stores the name of the agent's
93 process ID (PID) in this variable.
99 94
100 The agent exits automatically when the command given on the command line 95 SSH_AUTH_SOCK When ssh-agent starts, it creates a UNIX-domain socket and
101 terminates. 96 stores its pathname in this variable. It is accessible
97 only to the current user, but is easily abused by root or
98 another instance of the same user.
102 99
103FILES 100FILES
104 $TMPDIR/ssh-XXXXXXXXXX/agent.<ppid> 101 $TMPDIR/ssh-XXXXXXXXXX/agent.<ppid>
@@ -108,7 +105,7 @@ FILES
108 agent exits. 105 agent exits.
109 106
110SEE ALSO 107SEE ALSO
111 ssh(1), ssh-add(1), ssh-keygen(1), sshd(8) 108 ssh(1), ssh-add(1), ssh-keygen(1), ssh_config(5), sshd(8)
112 109
113AUTHORS 110AUTHORS
114 OpenSSH is a derivative of the original and free ssh 1.2.12 release by 111 OpenSSH is a derivative of the original and free ssh 1.2.12 release by
@@ -117,4 +114,4 @@ AUTHORS
117 created OpenSSH. Markus Friedl contributed the support for SSH protocol 114 created OpenSSH. Markus Friedl contributed the support for SSH protocol
118 versions 1.5 and 2.0. 115 versions 1.5 and 2.0.
119 116
120OpenBSD 6.6 November 30, 2016 OpenBSD 6.6 117OpenBSD 6.6 December 21, 2019 OpenBSD 6.6