xref: /freebsd/crypto/openssh/ssh.h (revision 6ae1554a5d9b318f8ad53ccc39fa5a961403da73)
1 /* $OpenBSD: ssh.h,v 1.79 2010/06/25 07:14:46 djm Exp $ */
2 
3 /*
4  * Author: Tatu Ylonen <ylo@cs.hut.fi>
5  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6  *                    All rights reserved
7  *
8  * As far as I am concerned, the code I have written for this software
9  * can be used freely for any purpose.  Any derived versions of this
10  * software must be clearly marked as such, and if the derived work is
11  * incompatible with the protocol description in the RFC file, it must be
12  * called by a name other than "ssh" or "Secure Shell".
13  */
14 
15 /* Cipher used for encrypting authentication files. */
16 #define SSH_AUTHFILE_CIPHER	SSH_CIPHER_3DES
17 
18 /* Default port number. */
19 #define SSH_DEFAULT_PORT	22
20 
21 /*
22  * Maximum number of RSA authentication identity files that can be specified
23  * in configuration files or on the command line.
24  */
25 #define SSH_MAX_IDENTITY_FILES		100
26 
27 /*
28  * Maximum length of lines in authorized_keys file.
29  * Current value permits 16kbit RSA and RSA1 keys and 8kbit DSA keys, with
30  * some room for options and comments.
31  */
32 #define SSH_MAX_PUBKEY_BYTES		8192
33 
34 /*
35  * Major protocol version.  Different version indicates major incompatibility
36  * that prevents communication.
37  *
38  * Minor protocol version.  Different version indicates minor incompatibility
39  * that does not prevent interoperation.
40  */
41 #define PROTOCOL_MAJOR_1	1
42 #define PROTOCOL_MINOR_1	5
43 
44 /* We support both SSH1 and SSH2 */
45 #define PROTOCOL_MAJOR_2	2
46 #define PROTOCOL_MINOR_2	0
47 
48 /*
49  * Name for the service.  The port named by this service overrides the
50  * default port if present.
51  */
52 #define SSH_SERVICE_NAME	"ssh"
53 
54 /*
55  * Name of the environment variable containing the process ID of the
56  * authentication agent.
57  */
58 #define SSH_AGENTPID_ENV_NAME	"SSH_AGENT_PID"
59 
60 /*
61  * Name of the environment variable containing the pathname of the
62  * authentication socket.
63  */
64 #define SSH_AUTHSOCKET_ENV_NAME "SSH_AUTH_SOCK"
65 
66 /*
67  * Environment variable for overwriting the default location of askpass
68  */
69 #define SSH_ASKPASS_ENV		"SSH_ASKPASS"
70 
71 /*
72  * Force host key length and server key length to differ by at least this
73  * many bits.  This is to make double encryption with rsaref work.
74  */
75 #define SSH_KEY_BITS_RESERVED		128
76 
77 /*
78  * Length of the session key in bytes.  (Specified as 256 bits in the
79  * protocol.)
80  */
81 #define SSH_SESSION_KEY_LENGTH		32
82 
83 /* Used to identify ``EscapeChar none'' */
84 #define SSH_ESCAPECHAR_NONE		-2
85 
86 /*
87  * unprivileged user when UsePrivilegeSeparation=yes;
88  * sshd will change its privileges to this user and its
89  * primary group.
90  */
91 #ifndef SSH_PRIVSEP_USER
92 #define SSH_PRIVSEP_USER		"sshd"
93 #endif
94 
95 /* Minimum modulus size (n) for RSA keys. */
96 #define SSH_RSA_MINIMUM_MODULUS_SIZE	768
97 
98 /* Listen backlog for sshd, ssh-agent and forwarding sockets */
99 #define SSH_LISTEN_BACKLOG		128
100