xref: /netbsd-src/crypto/external/bsd/openssh/dist/servconf.h (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: servconf.h,v 1.17 2018/04/06 18:59:00 christos Exp $	*/
2 /* $OpenBSD: servconf.h,v 1.130 2017/10/25 00:19:47 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  * Definitions for server configuration data and for the functions reading it.
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 SERVCONF_H
18 #define SERVCONF_H
19 
20 #ifdef WITH_LDAP_PUBKEY
21 #include "ldapauth.h"
22 #endif
23 
24 #define MAX_PORTS		256	/* Max # ports. */
25 
26 #define MAX_SUBSYSTEMS		256	/* Max # subsystems. */
27 
28 /* permit_root_login */
29 #define	PERMIT_NOT_SET		-1
30 #define	PERMIT_NO		0
31 #define	PERMIT_FORCED_ONLY	1
32 #define	PERMIT_NO_PASSWD	2
33 #define	PERMIT_YES		3
34 
35 /* use_privsep */
36 #define PRIVSEP_OFF		0
37 #define PRIVSEP_ON		1
38 #define PRIVSEP_NOSANDBOX	2
39 
40 /* AllowTCPForwarding */
41 #define FORWARD_DENY		0
42 #define FORWARD_REMOTE		(1)
43 #define FORWARD_LOCAL		(1<<1)
44 #define FORWARD_ALLOW		(FORWARD_REMOTE|FORWARD_LOCAL)
45 
46 /* PermitOpen */
47 #define PERMITOPEN_ANY		0
48 #define PERMITOPEN_NONE		-2
49 
50 #define DEFAULT_AUTH_FAIL_MAX	6	/* Default for MaxAuthTries */
51 #define DEFAULT_SESSIONS_MAX	10	/* Default for MaxSessions */
52 
53 /* Magic name for internal sftp-server */
54 #define INTERNAL_SFTP_NAME	"internal-sftp"
55 
56 struct ssh;
57 struct fwd_perm_list;
58 
59 /*
60  * Used to store addresses from ListenAddr directives. These may be
61  * incomplete, as they may specify addresses that need to be merged
62  * with any ports requested by ListenPort.
63  */
64 struct queued_listenaddr {
65 	char *addr;
66 	int port; /* <=0 if unspecified */
67 	char *rdomain;
68 };
69 
70 /* Resolved listen addresses, grouped by optional routing domain */
71 struct listenaddr {
72 	char *rdomain;
73 	struct addrinfo *addrs;
74 };
75 
76 typedef struct {
77 	u_int	num_ports;
78 	u_int	ports_from_cmdline;
79 	int	ports[MAX_PORTS];	/* Port number to listen on. */
80 	struct queued_listenaddr *queued_listen_addrs;
81 	u_int	num_queued_listens;
82 	struct listenaddr *listen_addrs;
83 	u_int	num_listen_addrs;
84 	int	address_family;		/* Address family used by the server. */
85 
86 	char	*routing_domain;	/* Bind session to routing domain */
87 
88 	char   **host_key_files;	/* Files containing host keys. */
89 	u_int	num_host_key_files;     /* Number of files for host keys. */
90 	char   **host_cert_files;	/* Files containing host certs. */
91 	u_int	num_host_cert_files;	/* Number of files for host certs. */
92 
93 	char   *host_key_agent;		/* ssh-agent socket for host keys. */
94 	char   *pid_file;		/* Where to put our pid */
95 	int     login_grace_time;	/* Disconnect if no auth in this time
96 					 * (sec). */
97 	int     permit_root_login;	/* PERMIT_*, see above */
98 	int     ignore_rhosts;	/* Ignore .rhosts and .shosts. */
99 	int     ignore_root_rhosts;	/* Ignore .rhosts and .shosts for root;
100 					   defaults to ignore_rhosts if not
101 					   given. */
102 	int     ignore_user_known_hosts;	/* Ignore ~/.ssh/known_hosts
103 						 * for RhostsRsaAuth */
104 	int     print_motd;	/* If true, print /etc/motd. */
105 	int	print_lastlog;	/* If true, print lastlog */
106 	int     x11_forwarding;	/* If true, permit inet (spoofing) X11 fwd. */
107 	int     x11_display_offset;	/* What DISPLAY number to start
108 					 * searching at */
109 	int     x11_use_localhost;	/* If true, use localhost for fake X11 server. */
110 	char   *xauth_location;	/* Location of xauth program */
111 	int	permit_tty;	/* If false, deny pty allocation */
112 	int	permit_user_rc;	/* If false, deny ~/.ssh/rc execution */
113 	int     strict_modes;	/* If true, require string home dir modes. */
114 	int     tcp_keep_alive;	/* If true, set SO_KEEPALIVE. */
115 	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
116 	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
117 	char   *ciphers;	/* Supported SSH2 ciphers. */
118 	char   *macs;		/* Supported SSH2 macs. */
119 	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
120 	struct ForwardOptions fwd_opts;	/* forwarding options */
121 	SyslogFacility log_facility;	/* Facility for system logging. */
122 	LogLevel log_level;	/* Level for system logging. */
123 	int     hostbased_authentication;	/* If true, permit ssh2 hostbased auth */
124 	int     hostbased_uses_name_from_packet_only; /* experimental */
125 	char   *hostbased_key_types;	/* Key types allowed for hostbased */
126 	char   *hostkeyalgorithms;	/* SSH2 server key types */
127 	int     pubkey_authentication;	/* If true, permit ssh2 pubkey authentication. */
128 	char   *pubkey_key_types;	/* Key types allowed for public key */
129 	int     kerberos_authentication;	/* If true, permit Kerberos
130 						 * authentication. */
131 	int     kerberos_or_local_passwd;	/* If true, permit kerberos
132 						 * and any other password
133 						 * authentication mechanism,
134 						 * such as SecurID or
135 						 * /etc/passwd */
136 	int     kerberos_ticket_cleanup;	/* If true, destroy ticket
137 						 * file on logout. */
138 	int	kerberos_tgt_passing;		/* If true, permit Kerberos TGT
139 						 * passing. */
140 	int     kerberos_get_afs_token;		/* If true, try to get AFS token if
141 						 * authenticated with Kerberos. */
142 #ifdef AFS
143 	int     afs_token_passing;      /* If true, permit AFS token passing. */
144 #endif
145 	int     gss_authentication;	/* If true, permit GSSAPI authentication */
146 	int     gss_cleanup_creds;	/* If true, destroy cred cache on logout */
147 	int     gss_strict_acceptor;	/* If true, restrict the GSSAPI acceptor name */
148 	int     password_authentication;	/* If true, permit password
149 						 * authentication. */
150 	int     kbd_interactive_authentication;	/* If true, permit */
151 	int     challenge_response_authentication;
152 	int     permit_empty_passwd;	/* If false, do not permit empty
153 					 * passwords. */
154 	int     permit_user_env;	/* If true, read ~/.ssh/environment */
155 	int     compression;	/* If true, compression is allowed */
156 	int	allow_tcp_forwarding; /* One of FORWARD_* */
157 	int	allow_streamlocal_forwarding; /* One of FORWARD_* */
158 	int	allow_agent_forwarding;
159 	int	disable_forwarding;
160 	u_int num_allow_users;
161 	char   **allow_users;
162 	u_int num_deny_users;
163 	char   **deny_users;
164 	u_int num_allow_groups;
165 	char   **allow_groups;
166 	u_int num_deny_groups;
167 	char   **deny_groups;
168 
169 	u_int num_subsystems;
170 	char   *subsystem_name[MAX_SUBSYSTEMS];
171 	char   *subsystem_command[MAX_SUBSYSTEMS];
172 	char   *subsystem_args[MAX_SUBSYSTEMS];
173 
174 	u_int num_accept_env;
175 	char   **accept_env;
176 
177 	int	max_startups_begin;
178 	int	max_startups_rate;
179 	int	max_startups;
180 	int	max_authtries;
181 	int	max_sessions;
182 	char   *banner;			/* SSH-2 banner message */
183 	int	use_dns;
184 	int	client_alive_interval;	/*
185 					 * poke the client this often to
186 					 * see if it's still there
187 					 */
188 	int	client_alive_count_max;	/*
189 					 * If the client is unresponsive
190 					 * for this many intervals above,
191 					 * disconnect the session
192 					 */
193 
194 	u_int	num_authkeys_files;	/* Files containing public keys */
195 	char   **authorized_keys_files;
196 
197 	int	use_pam;		/* Enable auth via PAM */
198 	int     none_enabled;           /* enable NONE cipher switch */
199 	int     tcp_rcv_buf_poll;       /* poll tcp rcv window in autotuning kernels*/
200 	int	hpn_disabled;		/* disable hpn functionality. false by default */
201 	int	hpn_buffer_size;	/* set the hpn buffer size - default 3MB */
202 
203 	char   *adm_forced_command;
204 
205 	int	permit_tun;
206 #ifdef WITH_LDAP_PUBKEY
207         ldap_opt_t lpk;
208 #endif
209 
210 	char   **permitted_opens;
211 	u_int   num_permitted_opens; /* May also be one of PERMITOPEN_* */
212 
213 	char   *chroot_directory;
214 	char   *revoked_keys_file;
215 	char   *trusted_user_ca_keys;
216 	char   *authorized_keys_command;
217 	char   *authorized_keys_command_user;
218 	char   *authorized_principals_file;
219 	char   *authorized_principals_command;
220 	char   *authorized_principals_command_user;
221 
222 	int64_t rekey_limit;
223 	int	rekey_interval;
224 
225 	char   *version_addendum;	/* Appended to SSH banner */
226 
227 	u_int	num_auth_methods;
228 	char   **auth_methods;
229 
230 	int	fingerprint_hash;
231 	int	expose_userauth_info;
232 }       ServerOptions;
233 
234 /* Information about the incoming connection as used by Match */
235 struct connection_info {
236 	const char *user;
237 	const char *host;	/* possibly resolved hostname */
238 	const char *address; 	/* remote address */
239 	const char *laddress;	/* local address */
240 	int lport;		/* local port */
241 	const char *rdomain;	/* routing domain if available */
242 };
243 
244 
245 /*
246  * These are string config options that must be copied between the
247  * Match sub-config and the main config, and must be sent from the
248  * privsep slave to the privsep master. We use a macro to ensure all
249  * the options are copied and the copies are done in the correct order.
250  *
251  * NB. an option must appear in servconf.c:copy_set_server_options() or
252  * COPY_MATCH_STRING_OPTS here but never both.
253  */
254 #define COPY_MATCH_STRING_OPTS() do { \
255 		M_CP_STROPT(banner); \
256 		M_CP_STROPT(trusted_user_ca_keys); \
257 		M_CP_STROPT(revoked_keys_file); \
258 		M_CP_STROPT(authorized_keys_command); \
259 		M_CP_STROPT(authorized_keys_command_user); \
260 		M_CP_STROPT(authorized_principals_file); \
261 		M_CP_STROPT(authorized_principals_command); \
262 		M_CP_STROPT(authorized_principals_command_user); \
263 		M_CP_STROPT(hostbased_key_types); \
264 		M_CP_STROPT(pubkey_key_types); \
265 		M_CP_STROPT(routing_domain); \
266 		M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \
267 		M_CP_STRARRAYOPT(allow_users, num_allow_users); \
268 		M_CP_STRARRAYOPT(deny_users, num_deny_users); \
269 		M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \
270 		M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \
271 		M_CP_STRARRAYOPT(accept_env, num_accept_env); \
272 		M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \
273 		M_CP_STRARRAYOPT(permitted_opens, num_permitted_opens); \
274 	} while (0)
275 
276 struct connection_info *get_connection_info(int, int);
277 void	 initialize_server_options(ServerOptions *);
278 void	 fill_default_server_options(ServerOptions *);
279 int	 process_server_config_line(ServerOptions *, char *, const char *, int,
280 	     int *, struct connection_info *);
281 void	 process_permitopen(struct ssh *ssh, ServerOptions *options);
282 void	 load_server_config(const char *, Buffer *);
283 void	 parse_server_config(ServerOptions *, const char *, Buffer *,
284 	     struct connection_info *);
285 void	 parse_server_match_config(ServerOptions *, struct connection_info *);
286 int	 parse_server_match_testspec(struct connection_info *, char *);
287 int	 server_match_spec_complete(struct connection_info *);
288 void	 copy_set_server_options(ServerOptions *, ServerOptions *, int);
289 void	 dump_config(ServerOptions *);
290 char	*derelativise_path(const char *);
291 void	 servconf_add_hostkey(const char *, const int,
292 	    ServerOptions *, const char *path);
293 void	 servconf_add_hostcert(const char *, const int,
294 	    ServerOptions *, const char *path);
295 
296 #endif				/* SERVCONF_H */
297