1/* $OpenBSD: ssh.h,v 1.90 2020/07/14 23:57:01 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 certificate files that can be specified
23 * in configuration files or on the command line.
24 */
25#define SSH_MAX_CERTIFICATE_FILES	100
26
27/*
28 * Maximum number of RSA authentication identity files that can be specified
29 * in configuration files or on the command line.
30 */
31#define SSH_MAX_IDENTITY_FILES		100
32
33/*
34 * Major protocol version.  Different version indicates major incompatibility
35 * that prevents communication.
36 *
37 * Minor protocol version.  Different version indicates minor incompatibility
38 * that does not prevent interoperation.
39 */
40#define PROTOCOL_MAJOR_1	1
41#define PROTOCOL_MINOR_1	5
42
43/* We support only SSH2 */
44#define PROTOCOL_MAJOR_2	2
45#define PROTOCOL_MINOR_2	0
46
47/*
48 * Name for the service.  The port named by this service overrides the
49 * default port if present.
50 */
51#define SSH_SERVICE_NAME	"ssh"
52
53/*
54 * Name of the environment variable containing the process ID of the
55 * authentication agent.
56 */
57#define SSH_AGENTPID_ENV_NAME	"SSH_AGENT_PID"
58
59/*
60 * Name of the environment variable containing the pathname of the
61 * authentication socket.
62 */
63#define SSH_AUTHSOCKET_ENV_NAME "SSH_AUTH_SOCK"
64
65/*
66 * Environment variable for overwriting the default location of askpass
67 */
68#define SSH_ASKPASS_ENV		"SSH_ASKPASS"
69
70/*
71 * Environment variable to control whether or not askpass is used.
72 */
73#define SSH_ASKPASS_REQUIRE_ENV		"SSH_ASKPASS_REQUIRE"
74
75/*
76 * Force host key length and server key length to differ by at least this
77 * many bits.  This is to make double encryption with rsaref work.
78 */
79#define SSH_KEY_BITS_RESERVED		128
80
81/*
82 * Length of the session key in bytes.  (Specified as 256 bits in the
83 * protocol.)
84 */
85#define SSH_SESSION_KEY_LENGTH		32
86
87/* Used to identify ``EscapeChar none'' */
88#define SSH_ESCAPECHAR_NONE		-2
89
90/*
91 * unprivileged user when UsePrivilegeSeparation=yes;
92 * sshd will change its privileges to this user and its
93 * primary group.
94 */
95#ifndef SSH_PRIVSEP_USER
96#define SSH_PRIVSEP_USER		"sshd"
97#endif
98
99/* Listen backlog for sshd, ssh-agent and forwarding sockets */
100#define SSH_LISTEN_BACKLOG		128
101
102/* Limits for banner exchange */
103#define SSH_MAX_BANNER_LEN		8192
104#define SSH_MAX_PRE_BANNER_LINES	1024
105