1/*	$NetBSD: readconf.h,v 1.34 2023/12/20 17:15:21 christos Exp $	*/
2/* $OpenBSD: readconf.h,v 1.154 2023/10/12 02:18:18 djm Exp $ */
3
4/*
5 * Author: Tatu Ylonen <ylo@cs.hut.fi>
6 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
7 *                    All rights reserved
8 * Functions for reading the configuration file.
9 *
10 * As far as I am concerned, the code I have written for this software
11 * can be used freely for any purpose.  Any derived versions of this
12 * software must be clearly marked as such, and if the derived work is
13 * incompatible with the protocol description in the RFC file, it must be
14 * called by a name other than "ssh" or "Secure Shell".
15 */
16
17#ifndef READCONF_H
18#define READCONF_H
19
20/* Data structure for representing option data. */
21
22#define SSH_MAX_HOSTS_FILES	32
23#define MAX_CANON_DOMAINS	32
24#define PATH_MAX_SUN		(sizeof((struct sockaddr_un *)0)->sun_path)
25
26struct allowed_cname {
27	char *source_list;
28	char *target_list;
29};
30
31typedef struct {
32	char   *host_arg;	/* Host arg as specified on command line. */
33	int     forward_agent;	/* Forward authentication agent. */
34	char   *forward_agent_sock_path; /* Optional path of the agent. */
35	int     forward_x11;	/* Forward X11 display. */
36	int     forward_x11_timeout;	/* Expiration for Cookies */
37	int     forward_x11_trusted;	/* Trust Forward X11 display. */
38	int     exit_on_forward_failure;	/* Exit if bind(2) fails for -L/-R */
39	char   *xauth_location;	/* Location for xauth program */
40	struct ForwardOptions fwd_opts;	/* forwarding options */
41	int     pubkey_authentication;	/* Try ssh2 pubkey authentication. */
42	int     hostbased_authentication;	/* ssh2's rhosts_rsa */
43#if defined(KRB4) || defined(KRB5)
44	int     kerberos_authentication;	/* Try Kerberos authentication. */
45#endif
46#if defined(AFS) || defined(KRB5)
47	int     kerberos_tgt_passing;	/* Try Kerberos TGT passing. */
48#endif
49#ifdef AFS
50	int     afs_token_passing;	/* Try AFS token passing. */
51#endif
52					/* Try S/Key or TIS, authentication. */
53	int     gss_authentication;	/* Try GSS authentication */
54	int     gss_deleg_creds;	/* Delegate GSS credentials */
55	int     password_authentication;	/* Try password
56						 * authentication. */
57	int     kbd_interactive_authentication; /* Try keyboard-interactive auth. */
58	char	*kbd_interactive_devices; /* Keyboard-interactive auth devices. */
59	int     batch_mode;	/* Batch mode: do not ask for passwords. */
60	int     check_host_ip;	/* Also keep track of keys for IP address */
61	int     strict_host_key_checking;	/* Strict host key checking. */
62	int     compression;	/* Compress packets in both directions. */
63	int     tcp_keep_alive;	/* Set SO_KEEPALIVE. */
64	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
65	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
66	int     tcp_rcv_buf; /* user switch to set tcp recv buffer */
67	int	tcp_rcv_buf_poll; /* Option to poll recv buf every window transfer */
68	int 	hpn_disabled; 	 /* Switch to disable HPN buffer management */
69	int	hpn_buffer_size; /* User definable size for HPN buffer window */
70
71	SyslogFacility log_facility;	/* Facility for system logging. */
72	LogLevel log_level;	/* Level for logging. */
73	u_int	num_log_verbose;	/* Verbose log overrides */
74	char   **log_verbose;
75	int     port;		/* Port to connect. */
76	int     address_family;
77	int     connection_attempts;	/* Max attempts (seconds) before
78					 * giving up */
79	int     connection_timeout;	/* Max time (seconds) before
80					 * aborting connection attempt */
81	int     number_of_password_prompts;	/* Max number of password
82						 * prompts. */
83	char   *ciphers;	/* SSH2 ciphers in order of preference. */
84	char   *macs;		/* SSH2 macs in order of preference. */
85	char   *hostkeyalgorithms;	/* SSH2 server key types in order of preference. */
86	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
87	char   *ca_sign_algorithms;	/* Allowed CA signature algorithms */
88	char   *hostname;	/* Real host to connect. */
89	char   *tag;		/* Configuration tag name. */
90	char   *host_key_alias;	/* hostname alias for .ssh/known_hosts */
91	char   *proxy_command;	/* Proxy command for connecting the host. */
92	char   *user;		/* User to log in as. */
93	int     escape_char;	/* Escape character; -2 = none */
94
95	u_int	num_system_hostfiles;	/* Paths for /etc/ssh/ssh_known_hosts */
96	char   *system_hostfiles[SSH_MAX_HOSTS_FILES];
97	u_int	num_user_hostfiles;	/* Path for $HOME/.ssh/known_hosts */
98	char   *user_hostfiles[SSH_MAX_HOSTS_FILES];
99	char   *preferred_authentications;
100	char   *bind_address;	/* local socket address for connection to sshd */
101	char   *bind_interface;	/* local interface for bind address */
102	int	ipv6_prefer_temporary; /* Prefer temporary IPv6 address */
103	char   *pkcs11_provider; /* PKCS#11 provider */
104	char   *sk_provider; /* Security key provider */
105	int	verify_host_key_dns;	/* Verify host key using DNS */
106
107	int     num_identity_files;	/* Number of files for RSA/DSA identities. */
108	char   *identity_files[SSH_MAX_IDENTITY_FILES];
109	int    identity_file_userprovided[SSH_MAX_IDENTITY_FILES];
110	struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES];
111
112	int	num_certificate_files; /* Number of extra certificates for ssh. */
113	char	*certificate_files[SSH_MAX_CERTIFICATE_FILES];
114	int	certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES];
115	struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
116
117	int	add_keys_to_agent;
118	int	add_keys_to_agent_lifespan;
119	char   *identity_agent;		/* Optional path to ssh-agent socket */
120
121	/* Local TCP/IP forward requests. */
122	int     num_local_forwards;
123	struct Forward *local_forwards;
124
125	/* Remote TCP/IP forward requests. */
126	int     num_remote_forwards;
127	struct Forward *remote_forwards;
128	int	clear_forwardings;
129
130	/* Restrict remote dynamic forwarding */
131	char  **permitted_remote_opens;
132	u_int	num_permitted_remote_opens;
133
134	/* stdio forwarding (-W) host and port */
135	char   *stdio_forward_host;
136	int	stdio_forward_port;
137
138	int	enable_ssh_keysign;
139	int64_t rekey_limit;
140	int	rekey_interval;
141	int     none_switch;    /* Use none cipher */
142	int     none_enabled;   /* Allow none to be used */
143	int	no_host_authentication_for_localhost;
144	int	identities_only;
145	int	server_alive_interval;
146	int	server_alive_count_max;
147
148	u_int	num_send_env;
149	char	**send_env;
150	u_int	num_setenv;
151	char	**setenv;
152
153	char	*control_path;
154	int	control_master;
155	int     control_persist; /* ControlPersist flag */
156	int     control_persist_timeout; /* ControlPersist timeout (seconds) */
157
158	int	hash_known_hosts;
159
160	int	tun_open;	/* tun(4) */
161	int     tun_local;	/* force tun device (optional) */
162	int     tun_remote;	/* force tun device (optional) */
163
164	char	*local_command;
165	int	permit_local_command;
166	char	*remote_command;
167	int	visual_host_key;
168
169	int	request_tty;
170	int	send_version_first;
171	int	session_type;
172	int	stdin_null;
173	int	fork_after_authentication;
174
175	int	proxy_use_fdpass;
176
177	int	num_canonical_domains;
178	char	*canonical_domains[MAX_CANON_DOMAINS];
179	int	canonicalize_hostname;
180	int	canonicalize_max_dots;
181	int	canonicalize_fallback_local;
182	int	num_permitted_cnames;
183	struct allowed_cname permitted_cnames[MAX_CANON_DOMAINS];
184
185	char	*revoked_host_keys;
186
187	int	 fingerprint_hash;
188
189	int	 update_hostkeys; /* one of SSH_UPDATE_HOSTKEYS_* */
190
191	char   *hostbased_accepted_algos;
192	char   *pubkey_accepted_algos;
193
194	char   *jump_user;
195	char   *jump_host;
196	int	jump_port;
197	char   *jump_extra;
198
199	char   *known_hosts_command;
200
201	int	required_rsa_size;	/* minimum size of RSA keys */
202	int	enable_escape_commandline;	/* ~C commandline */
203	int	obscure_keystroke_timing_interval;
204
205	char	**channel_timeouts;	/* inactivity timeout by channel type */
206	u_int	num_channel_timeouts;
207
208	char	*ignored_unknown; /* Pattern list of unknown tokens to ignore */
209}       Options;
210
211#define SSH_PUBKEY_AUTH_NO	0x00
212#define SSH_PUBKEY_AUTH_UNBOUND	0x01
213#define SSH_PUBKEY_AUTH_HBOUND	0x02
214#define SSH_PUBKEY_AUTH_ALL	0x03
215
216#define SSH_CANONICALISE_NO	0
217#define SSH_CANONICALISE_YES	1
218#define SSH_CANONICALISE_ALWAYS	2
219
220#define SSHCTL_MASTER_NO	0
221#define SSHCTL_MASTER_YES	1
222#define SSHCTL_MASTER_AUTO	2
223#define SSHCTL_MASTER_ASK	3
224#define SSHCTL_MASTER_AUTO_ASK	4
225
226#define REQUEST_TTY_AUTO	0
227#define REQUEST_TTY_NO		1
228#define REQUEST_TTY_YES		2
229#define REQUEST_TTY_FORCE	3
230
231#define SESSION_TYPE_NONE	0
232#define SESSION_TYPE_SUBSYSTEM	1
233#define SESSION_TYPE_DEFAULT	2
234
235#define SSHCONF_CHECKPERM	1  /* check permissions on config file */
236#define SSHCONF_USERCONF	2  /* user provided config file not system */
237#define SSHCONF_FINAL		4  /* Final pass over config, after canon. */
238#define SSHCONF_NEVERMATCH	8  /* Match/Host never matches; internal only */
239
240#define SSH_UPDATE_HOSTKEYS_NO	0
241#define SSH_UPDATE_HOSTKEYS_YES	1
242#define SSH_UPDATE_HOSTKEYS_ASK	2
243
244#define SSH_STRICT_HOSTKEY_OFF	0
245#define SSH_STRICT_HOSTKEY_NEW	1
246#define SSH_STRICT_HOSTKEY_YES	2
247#define SSH_STRICT_HOSTKEY_ASK	3
248
249/* ObscureKeystrokes parameters */
250#define SSH_KEYSTROKE_DEFAULT_INTERVAL_MS	20
251#define SSH_KEYSTROKE_CHAFF_MIN_MS		1024
252#define SSH_KEYSTROKE_CHAFF_RNG_MS		2048
253
254const char *kex_default_pk_alg(void);
255char	*ssh_connection_hash(const char *thishost, const char *host,
256    const char *portstr, const char *user, const char *jump_host);
257void     initialize_options(Options *);
258int      fill_default_options(Options *);
259void	 fill_default_options_for_canonicalization(Options *);
260void	 free_options(Options *o);
261int	 process_config_line(Options *, struct passwd *, const char *,
262    const char *, char *, const char *, int, int *, int);
263int	 read_config_file(const char *, struct passwd *, const char *,
264    const char *, Options *, int, int *);
265int	 parse_forward(struct Forward *, const char *, int, int);
266int	 parse_jump(const char *, Options *, int);
267int	 parse_ssh_uri(const char *, char **, char **, int *);
268int	 default_ssh_port(void);
269int	 option_clear_or_none(const char *);
270int	 config_has_permitted_cnames(Options *);
271void	 dump_client_config(Options *o, const char *host);
272
273void	 add_local_forward(Options *, const struct Forward *);
274void	 add_remote_forward(Options *, const struct Forward *);
275void	 add_identity_file(Options *, const char *, const char *, int);
276void	 add_certificate_file(Options *, const char *, int);
277
278#endif				/* READCONF_H */
279