xref: /freebsd/crypto/openssh/readconf.h (revision 4ac8f4067096a9d4a00e41cd53bd5c4fa295fd15)
1 /* $OpenBSD: readconf.h,v 1.148 2022/09/17 10:33:18 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 
25 struct allowed_cname {
26 	char *source_list;
27 	char *target_list;
28 };
29 
30 typedef struct {
31 	int     forward_agent;	/* Forward authentication agent. */
32 	char   *forward_agent_sock_path; /* Optional path of the agent. */
33 	int     forward_x11;	/* Forward X11 display. */
34 	int     forward_x11_timeout;	/* Expiration for Cookies */
35 	int     forward_x11_trusted;	/* Trust Forward X11 display. */
36 	int     exit_on_forward_failure;	/* Exit if bind(2) fails for -L/-R */
37 	char   *xauth_location;	/* Location for xauth program */
38 	struct ForwardOptions fwd_opts;	/* forwarding options */
39 	int     pubkey_authentication;	/* Try ssh2 pubkey authentication. */
40 	int     hostbased_authentication;	/* ssh2's rhosts_rsa */
41 	int     gss_authentication;	/* Try GSS authentication */
42 	int     gss_deleg_creds;	/* Delegate GSS credentials */
43 	int     password_authentication;	/* Try password
44 						 * authentication. */
45 	int     kbd_interactive_authentication; /* Try keyboard-interactive auth. */
46 	char	*kbd_interactive_devices; /* Keyboard-interactive auth devices. */
47 	int     batch_mode;	/* Batch mode: do not ask for passwords. */
48 	int     check_host_ip;	/* Also keep track of keys for IP address */
49 	int     strict_host_key_checking;	/* Strict host key checking. */
50 	int     compression;	/* Compress packets in both directions. */
51 	int     tcp_keep_alive;	/* Set SO_KEEPALIVE. */
52 	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
53 	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
54 	SyslogFacility log_facility;	/* Facility for system logging. */
55 	LogLevel log_level;	/* Level for logging. */
56 	u_int	num_log_verbose;	/* Verbose log overrides */
57 	char   **log_verbose;
58 	int     port;		/* Port to connect. */
59 	int     address_family;
60 	int     connection_attempts;	/* Max attempts (seconds) before
61 					 * giving up */
62 	int     connection_timeout;	/* Max time (seconds) before
63 					 * aborting connection attempt */
64 	int     number_of_password_prompts;	/* Max number of password
65 						 * prompts. */
66 	char   *ciphers;	/* SSH2 ciphers in order of preference. */
67 	char   *macs;		/* SSH2 macs in order of preference. */
68 	char   *hostkeyalgorithms;	/* SSH2 server key types in order of preference. */
69 	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
70 	char   *ca_sign_algorithms;	/* Allowed CA signature algorithms */
71 	char   *hostname;	/* Real host to connect. */
72 	char   *host_key_alias;	/* hostname alias for .ssh/known_hosts */
73 	char   *proxy_command;	/* Proxy command for connecting the host. */
74 	char   *user;		/* User to log in as. */
75 	int     escape_char;	/* Escape character; -2 = none */
76 
77 	u_int	num_system_hostfiles;	/* Paths for /etc/ssh/ssh_known_hosts */
78 	char   *system_hostfiles[SSH_MAX_HOSTS_FILES];
79 	u_int	num_user_hostfiles;	/* Path for $HOME/.ssh/known_hosts */
80 	char   *user_hostfiles[SSH_MAX_HOSTS_FILES];
81 	char   *preferred_authentications;
82 	char   *bind_address;	/* local socket address for connection to sshd */
83 	char   *bind_interface;	/* local interface for bind address */
84 	char   *pkcs11_provider; /* PKCS#11 provider */
85 	char   *sk_provider; /* Security key provider */
86 	int	verify_host_key_dns;	/* Verify host key using DNS */
87 
88 	int     num_identity_files;	/* Number of files for RSA/DSA identities. */
89 	char   *identity_files[SSH_MAX_IDENTITY_FILES];
90 	int    identity_file_userprovided[SSH_MAX_IDENTITY_FILES];
91 	struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES];
92 
93 	int	num_certificate_files; /* Number of extra certificates for ssh. */
94 	char	*certificate_files[SSH_MAX_CERTIFICATE_FILES];
95 	int	certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES];
96 	struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
97 
98 	int	add_keys_to_agent;
99 	int	add_keys_to_agent_lifespan;
100 	char   *identity_agent;		/* Optional path to ssh-agent socket */
101 
102 	/* Local TCP/IP forward requests. */
103 	int     num_local_forwards;
104 	struct Forward *local_forwards;
105 
106 	/* Remote TCP/IP forward requests. */
107 	int     num_remote_forwards;
108 	struct Forward *remote_forwards;
109 	int	clear_forwardings;
110 
111 	/* Restrict remote dynamic forwarding */
112 	char  **permitted_remote_opens;
113 	u_int	num_permitted_remote_opens;
114 
115 	/* stdio forwarding (-W) host and port */
116 	char   *stdio_forward_host;
117 	int	stdio_forward_port;
118 
119 	int	enable_ssh_keysign;
120 	int64_t rekey_limit;
121 	int	rekey_interval;
122 	int	no_host_authentication_for_localhost;
123 	int	identities_only;
124 	int	server_alive_interval;
125 	int	server_alive_count_max;
126 
127 	u_int	num_send_env;
128 	char	**send_env;
129 	u_int	num_setenv;
130 	char	**setenv;
131 
132 	char	*control_path;
133 	int	control_master;
134 	int     control_persist; /* ControlPersist flag */
135 	int     control_persist_timeout; /* ControlPersist timeout (seconds) */
136 
137 	int	hash_known_hosts;
138 
139 	int	tun_open;	/* tun(4) */
140 	int     tun_local;	/* force tun device (optional) */
141 	int     tun_remote;	/* force tun device (optional) */
142 
143 	char	*local_command;
144 	int	permit_local_command;
145 	char	*remote_command;
146 	int	visual_host_key;
147 
148 	int	request_tty;
149 	int	session_type;
150 	int	stdin_null;
151 	int	fork_after_authentication;
152 
153 	int	proxy_use_fdpass;
154 
155 	int	num_canonical_domains;
156 	char	*canonical_domains[MAX_CANON_DOMAINS];
157 	int	canonicalize_hostname;
158 	int	canonicalize_max_dots;
159 	int	canonicalize_fallback_local;
160 	int	num_permitted_cnames;
161 	struct allowed_cname permitted_cnames[MAX_CANON_DOMAINS];
162 
163 	char	*revoked_host_keys;
164 
165 	int	 fingerprint_hash;
166 
167 	int	 update_hostkeys; /* one of SSH_UPDATE_HOSTKEYS_* */
168 
169 	char   *hostbased_accepted_algos;
170 	char   *pubkey_accepted_algos;
171 
172 	char   *jump_user;
173 	char   *jump_host;
174 	int	jump_port;
175 	char   *jump_extra;
176 
177 	char   *known_hosts_command;
178 
179 	int	required_rsa_size;	/* minimum size of RSA keys */
180 
181 	char	*ignored_unknown; /* Pattern list of unknown tokens to ignore */
182 }       Options;
183 
184 #define SSH_PUBKEY_AUTH_NO	0x00
185 #define SSH_PUBKEY_AUTH_UNBOUND	0x01
186 #define SSH_PUBKEY_AUTH_HBOUND	0x02
187 #define SSH_PUBKEY_AUTH_ALL	0x03
188 
189 #define SSH_CANONICALISE_NO	0
190 #define SSH_CANONICALISE_YES	1
191 #define SSH_CANONICALISE_ALWAYS	2
192 
193 #define SSHCTL_MASTER_NO	0
194 #define SSHCTL_MASTER_YES	1
195 #define SSHCTL_MASTER_AUTO	2
196 #define SSHCTL_MASTER_ASK	3
197 #define SSHCTL_MASTER_AUTO_ASK	4
198 
199 #define REQUEST_TTY_AUTO	0
200 #define REQUEST_TTY_NO		1
201 #define REQUEST_TTY_YES		2
202 #define REQUEST_TTY_FORCE	3
203 
204 #define SESSION_TYPE_NONE	0
205 #define SESSION_TYPE_SUBSYSTEM	1
206 #define SESSION_TYPE_DEFAULT	2
207 
208 #define SSHCONF_CHECKPERM	1  /* check permissions on config file */
209 #define SSHCONF_USERCONF	2  /* user provided config file not system */
210 #define SSHCONF_FINAL		4  /* Final pass over config, after canon. */
211 #define SSHCONF_NEVERMATCH	8  /* Match/Host never matches; internal only */
212 
213 #define SSH_UPDATE_HOSTKEYS_NO	0
214 #define SSH_UPDATE_HOSTKEYS_YES	1
215 #define SSH_UPDATE_HOSTKEYS_ASK	2
216 
217 #define SSH_STRICT_HOSTKEY_OFF	0
218 #define SSH_STRICT_HOSTKEY_NEW	1
219 #define SSH_STRICT_HOSTKEY_YES	2
220 #define SSH_STRICT_HOSTKEY_ASK	3
221 
222 const char *kex_default_pk_alg(void);
223 char	*ssh_connection_hash(const char *thishost, const char *host,
224     const char *portstr, const char *user);
225 void     initialize_options(Options *);
226 int      fill_default_options(Options *);
227 void	 fill_default_options_for_canonicalization(Options *);
228 void	 free_options(Options *o);
229 int	 process_config_line(Options *, struct passwd *, const char *,
230     const char *, char *, const char *, int, int *, int);
231 int	 read_config_file(const char *, struct passwd *, const char *,
232     const char *, Options *, int, int *);
233 int	 parse_forward(struct Forward *, const char *, int, int);
234 int	 parse_jump(const char *, Options *, int);
235 int	 parse_ssh_uri(const char *, char **, char **, int *);
236 int	 default_ssh_port(void);
237 int	 option_clear_or_none(const char *);
238 int	 config_has_permitted_cnames(Options *);
239 void	 dump_client_config(Options *o, const char *host);
240 
241 void	 add_local_forward(Options *, const struct Forward *);
242 void	 add_remote_forward(Options *, const struct Forward *);
243 void	 add_identity_file(Options *, const char *, const char *, int);
244 void	 add_certificate_file(Options *, const char *, int);
245 
246 #endif				/* READCONF_H */
247