1/* $OpenBSD: readconf.h,v 1.156 2024/03/04 02:16:11 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 * Functions for reading the configuration file.
8 *
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
16#ifndef READCONF_H
17#define READCONF_H
18
19/* Data structure for representing option data. */
20
21#define SSH_MAX_HOSTS_FILES	32
22#define MAX_CANON_DOMAINS	32
23#define PATH_MAX_SUN		(sizeof((struct sockaddr_un *)0)->sun_path)
24
25struct allowed_cname {
26	char *source_list;
27	char *target_list;
28};
29
30typedef struct {
31	char   *host_arg;	/* Host arg as specified on command line. */
32	int     forward_agent;	/* Forward authentication agent. */
33	char   *forward_agent_sock_path; /* Optional path of the agent. */
34	int     forward_x11;	/* Forward X11 display. */
35	int     forward_x11_timeout;	/* Expiration for Cookies */
36	int     forward_x11_trusted;	/* Trust Forward X11 display. */
37	int     exit_on_forward_failure;	/* Exit if bind(2) fails for -L/-R */
38	char   *xauth_location;	/* Location for xauth program */
39	struct ForwardOptions fwd_opts;	/* forwarding options */
40	int     pubkey_authentication;	/* Try ssh2 pubkey authentication. */
41	int     hostbased_authentication;	/* ssh2's rhosts_rsa */
42	int     gss_authentication;	/* Try GSS authentication */
43	int     gss_deleg_creds;	/* Delegate GSS credentials */
44	int     password_authentication;	/* Try password
45						 * authentication. */
46	int     kbd_interactive_authentication; /* Try keyboard-interactive auth. */
47	char	*kbd_interactive_devices; /* Keyboard-interactive auth devices. */
48	int     batch_mode;	/* Batch mode: do not ask for passwords. */
49	int     check_host_ip;	/* Also keep track of keys for IP address */
50	int     strict_host_key_checking;	/* Strict host key checking. */
51	int     compression;	/* Compress packets in both directions. */
52	int     tcp_keep_alive;	/* Set SO_KEEPALIVE. */
53	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
54	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
55	SyslogFacility log_facility;	/* Facility for system logging. */
56	LogLevel log_level;	/* Level for logging. */
57	u_int	num_log_verbose;	/* Verbose log overrides */
58	char   **log_verbose;
59	int     port;		/* Port to connect. */
60	int     address_family;
61	int     connection_attempts;	/* Max attempts (seconds) before
62					 * giving up */
63	int     connection_timeout;	/* Max time (seconds) before
64					 * aborting connection attempt */
65	int     number_of_password_prompts;	/* Max number of password
66						 * prompts. */
67	char   *ciphers;	/* SSH2 ciphers in order of preference. */
68	char   *macs;		/* SSH2 macs in order of preference. */
69	char   *hostkeyalgorithms;	/* SSH2 server key types in order of preference. */
70	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
71	char   *ca_sign_algorithms;	/* Allowed CA signature algorithms */
72	char   *hostname;	/* Real host to connect. */
73	char   *tag;		/* Configuration tag name. */
74	char   *host_key_alias;	/* hostname alias for .ssh/known_hosts */
75	char   *proxy_command;	/* Proxy command for connecting the host. */
76	char   *user;		/* User to log in as. */
77	int     escape_char;	/* Escape character; -2 = none */
78
79	u_int	num_system_hostfiles;	/* Paths for /etc/ssh/ssh_known_hosts */
80	char   *system_hostfiles[SSH_MAX_HOSTS_FILES];
81	u_int	num_user_hostfiles;	/* Path for $HOME/.ssh/known_hosts */
82	char   *user_hostfiles[SSH_MAX_HOSTS_FILES];
83	char   *preferred_authentications;
84	char   *bind_address;	/* local socket address for connection to sshd */
85	char   *bind_interface;	/* local interface for bind address */
86	char   *pkcs11_provider; /* PKCS#11 provider */
87	char   *sk_provider; /* Security key provider */
88	int	verify_host_key_dns;	/* Verify host key using DNS */
89
90	int     num_identity_files;	/* Number of files for identities. */
91	char   *identity_files[SSH_MAX_IDENTITY_FILES];
92	int    identity_file_userprovided[SSH_MAX_IDENTITY_FILES];
93	struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES];
94
95	int	num_certificate_files; /* Number of extra certificates for ssh. */
96	char	*certificate_files[SSH_MAX_CERTIFICATE_FILES];
97	int	certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES];
98	struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
99
100	int	add_keys_to_agent;
101	int	add_keys_to_agent_lifespan;
102	char   *identity_agent;		/* Optional path to ssh-agent socket */
103
104	/* Local TCP/IP forward requests. */
105	int     num_local_forwards;
106	struct Forward *local_forwards;
107
108	/* Remote TCP/IP forward requests. */
109	int     num_remote_forwards;
110	struct Forward *remote_forwards;
111	int	clear_forwardings;
112
113	/* Restrict remote dynamic forwarding */
114	char  **permitted_remote_opens;
115	u_int	num_permitted_remote_opens;
116
117	/* stdio forwarding (-W) host and port */
118	char   *stdio_forward_host;
119	int	stdio_forward_port;
120
121	int	enable_ssh_keysign;
122	int64_t rekey_limit;
123	int	rekey_interval;
124	int	no_host_authentication_for_localhost;
125	int	identities_only;
126	int	server_alive_interval;
127	int	server_alive_count_max;
128
129	u_int	num_send_env;
130	char	**send_env;
131	u_int	num_setenv;
132	char	**setenv;
133
134	char	*control_path;
135	int	control_master;
136	int     control_persist; /* ControlPersist flag */
137	int     control_persist_timeout; /* ControlPersist timeout (seconds) */
138
139	int	hash_known_hosts;
140
141	int	tun_open;	/* tun(4) */
142	int     tun_local;	/* force tun device (optional) */
143	int     tun_remote;	/* force tun device (optional) */
144
145	char	*local_command;
146	int	permit_local_command;
147	char	*remote_command;
148	int	visual_host_key;
149
150	int	request_tty;
151	int	session_type;
152	int	stdin_null;
153	int	fork_after_authentication;
154
155	int	proxy_use_fdpass;
156
157	int	num_canonical_domains;
158	char	**canonical_domains;
159	int	canonicalize_hostname;
160	int	canonicalize_max_dots;
161	int	canonicalize_fallback_local;
162	int	num_permitted_cnames;
163	struct allowed_cname *permitted_cnames;
164
165	char	*revoked_host_keys;
166
167	int	 fingerprint_hash;
168
169	int	 update_hostkeys; /* one of SSH_UPDATE_HOSTKEYS_* */
170
171	char   *hostbased_accepted_algos;
172	char   *pubkey_accepted_algos;
173
174	char   *jump_user;
175	char   *jump_host;
176	int	jump_port;
177	char   *jump_extra;
178
179	char   *known_hosts_command;
180
181	int	required_rsa_size;	/* minimum size of RSA keys */
182	int	enable_escape_commandline;	/* ~C commandline */
183	int	obscure_keystroke_timing_interval;
184
185	char	**channel_timeouts;	/* inactivity timeout by channel type */
186	u_int	num_channel_timeouts;
187
188	char	*ignored_unknown; /* Pattern list of unknown tokens to ignore */
189}       Options;
190
191#define SSH_PUBKEY_AUTH_NO	0x00
192#define SSH_PUBKEY_AUTH_UNBOUND	0x01
193#define SSH_PUBKEY_AUTH_HBOUND	0x02
194#define SSH_PUBKEY_AUTH_ALL	0x03
195
196#define SSH_CANONICALISE_NO	0
197#define SSH_CANONICALISE_YES	1
198#define SSH_CANONICALISE_ALWAYS	2
199
200#define SSHCTL_MASTER_NO	0
201#define SSHCTL_MASTER_YES	1
202#define SSHCTL_MASTER_AUTO	2
203#define SSHCTL_MASTER_ASK	3
204#define SSHCTL_MASTER_AUTO_ASK	4
205
206#define REQUEST_TTY_AUTO	0
207#define REQUEST_TTY_NO		1
208#define REQUEST_TTY_YES		2
209#define REQUEST_TTY_FORCE	3
210
211#define SESSION_TYPE_NONE	0
212#define SESSION_TYPE_SUBSYSTEM	1
213#define SESSION_TYPE_DEFAULT	2
214
215#define SSHCONF_CHECKPERM	1  /* check permissions on config file */
216#define SSHCONF_USERCONF	2  /* user provided config file not system */
217#define SSHCONF_FINAL		4  /* Final pass over config, after canon. */
218#define SSHCONF_NEVERMATCH	8  /* Match/Host never matches; internal only */
219
220#define SSH_UPDATE_HOSTKEYS_NO	0
221#define SSH_UPDATE_HOSTKEYS_YES	1
222#define SSH_UPDATE_HOSTKEYS_ASK	2
223
224#define SSH_STRICT_HOSTKEY_OFF	0
225#define SSH_STRICT_HOSTKEY_NEW	1
226#define SSH_STRICT_HOSTKEY_YES	2
227#define SSH_STRICT_HOSTKEY_ASK	3
228
229/* ObscureKeystrokes parameters */
230#define SSH_KEYSTROKE_DEFAULT_INTERVAL_MS	20
231#define SSH_KEYSTROKE_CHAFF_MIN_MS		1024
232#define SSH_KEYSTROKE_CHAFF_RNG_MS		2048
233
234const char *kex_default_pk_alg(void);
235char	*ssh_connection_hash(const char *thishost, const char *host,
236    const char *portstr, const char *user, const char *jump_host);
237void     initialize_options(Options *);
238int      fill_default_options(Options *);
239void	 fill_default_options_for_canonicalization(Options *);
240void	 free_options(Options *o);
241int	 process_config_line(Options *, struct passwd *, const char *,
242    const char *, char *, const char *, int, int *, int);
243int	 read_config_file(const char *, struct passwd *, const char *,
244    const char *, Options *, int, int *);
245int	 parse_forward(struct Forward *, const char *, int, int);
246int	 parse_jump(const char *, Options *, int);
247int	 parse_ssh_uri(const char *, char **, char **, int *);
248int	 default_ssh_port(void);
249int	 option_clear_or_none(const char *);
250int	 config_has_permitted_cnames(Options *);
251void	 dump_client_config(Options *o, const char *host);
252
253void	 add_local_forward(Options *, const struct Forward *);
254void	 add_remote_forward(Options *, const struct Forward *);
255void	 add_identity_file(Options *, const char *, const char *, int);
256void	 add_certificate_file(Options *, const char *, int);
257
258#endif				/* READCONF_H */
259