1/* $OpenBSD: servconf.h,v 1.137 2018/09/20 03:28:06 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 * Definitions for server configuration data and for the functions reading it.
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 SERVCONF_H
17#define SERVCONF_H
18
19#define MAX_PORTS		256	/* Max # ports. */
20
21#define MAX_SUBSYSTEMS		256	/* Max # subsystems. */
22
23/* permit_root_login */
24#define	PERMIT_NOT_SET		-1
25#define	PERMIT_NO		0
26#define	PERMIT_FORCED_ONLY	1
27#define	PERMIT_NO_PASSWD	2
28#define	PERMIT_YES		3
29
30/* use_privsep */
31#define PRIVSEP_OFF		0
32#define PRIVSEP_ON		1
33#define PRIVSEP_NOSANDBOX	2
34
35/* PermitOpen */
36#define PERMITOPEN_ANY		0
37#define PERMITOPEN_NONE		-2
38
39#define DEFAULT_AUTH_FAIL_MAX	6	/* Default for MaxAuthTries */
40#define DEFAULT_SESSIONS_MAX	10	/* Default for MaxSessions */
41
42/* Magic name for internal sftp-server */
43#define INTERNAL_SFTP_NAME	"internal-sftp"
44
45struct ssh;
46struct fwd_perm_list;
47
48/*
49 * Used to store addresses from ListenAddr directives. These may be
50 * incomplete, as they may specify addresses that need to be merged
51 * with any ports requested by ListenPort.
52 */
53struct queued_listenaddr {
54	char *addr;
55	int port; /* <=0 if unspecified */
56	char *rdomain;
57};
58
59/* Resolved listen addresses, grouped by optional routing domain */
60struct listenaddr {
61	char *rdomain;
62	struct addrinfo *addrs;
63};
64
65typedef struct {
66	u_int	num_ports;
67	u_int	ports_from_cmdline;
68	int	ports[MAX_PORTS];	/* Port number to listen on. */
69	struct queued_listenaddr *queued_listen_addrs;
70	u_int	num_queued_listens;
71	struct listenaddr *listen_addrs;
72	u_int	num_listen_addrs;
73	int	address_family;		/* Address family used by the server. */
74
75	char	*routing_domain;	/* Bind session to routing domain */
76
77	char   **host_key_files;	/* Files containing host keys. */
78	u_int	num_host_key_files;     /* Number of files for host keys. */
79	char   **host_cert_files;	/* Files containing host certs. */
80	u_int	num_host_cert_files;	/* Number of files for host certs. */
81
82	char   *host_key_agent;		/* ssh-agent socket for host keys. */
83	char   *pid_file;		/* Where to put our pid */
84	int     login_grace_time;	/* Disconnect if no auth in this time
85					 * (sec). */
86	int     permit_root_login;	/* PERMIT_*, see above */
87	int     ignore_rhosts;	/* Ignore .rhosts and .shosts. */
88	int     ignore_user_known_hosts;	/* Ignore ~/.ssh/known_hosts
89						 * for RhostsRsaAuth */
90	int     print_motd;	/* If true, print /etc/motd. */
91	int	print_lastlog;	/* If true, print lastlog */
92	int     x11_forwarding;	/* If true, permit inet (spoofing) X11 fwd. */
93	int     x11_display_offset;	/* What DISPLAY number to start
94					 * searching at */
95	int     x11_use_localhost;	/* If true, use localhost for fake X11 server. */
96	char   *xauth_location;	/* Location of xauth program */
97	int	permit_tty;	/* If false, deny pty allocation */
98	int	permit_user_rc;	/* If false, deny ~/.ssh/rc execution */
99	int     strict_modes;	/* If true, require string home dir modes. */
100	int     tcp_keep_alive;	/* If true, set SO_KEEPALIVE. */
101	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
102	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
103	char   *ciphers;	/* Supported SSH2 ciphers. */
104	char   *macs;		/* Supported SSH2 macs. */
105	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
106	struct ForwardOptions fwd_opts;	/* forwarding options */
107	SyslogFacility log_facility;	/* Facility for system logging. */
108	LogLevel log_level;	/* Level for system logging. */
109	int     hostbased_authentication;	/* If true, permit ssh2 hostbased auth */
110	int     hostbased_uses_name_from_packet_only; /* experimental */
111	char   *hostbased_key_types;	/* Key types allowed for hostbased */
112	char   *hostkeyalgorithms;	/* SSH2 server key types */
113	char   *ca_sign_algorithms;	/* Allowed CA signature algorithms */
114	int     pubkey_authentication;	/* If true, permit ssh2 pubkey authentication. */
115	char   *pubkey_key_types;	/* Key types allowed for public key */
116	int     kerberos_authentication;	/* If true, permit Kerberos
117						 * authentication. */
118	int     kerberos_or_local_passwd;	/* If true, permit kerberos
119						 * and any other password
120						 * authentication mechanism,
121						 * such as SecurID or
122						 * /etc/passwd */
123	int     kerberos_ticket_cleanup;	/* If true, destroy ticket
124						 * file on logout. */
125	int     kerberos_get_afs_token;		/* If true, try to get AFS token if
126						 * authenticated with Kerberos. */
127	int     gss_authentication;	/* If true, permit GSSAPI authentication */
128	int     gss_cleanup_creds;	/* If true, destroy cred cache on logout */
129	int     gss_strict_acceptor;	/* If true, restrict the GSSAPI acceptor name */
130	int     password_authentication;	/* If true, permit password
131						 * authentication. */
132	int     kbd_interactive_authentication;	/* If true, permit */
133	int     challenge_response_authentication;
134	int     permit_empty_passwd;	/* If false, do not permit empty
135					 * passwords. */
136	int     permit_user_env;	/* If true, read ~/.ssh/environment */
137	char   *permit_user_env_whitelist; /* pattern-list whitelist */
138	int     compression;	/* If true, compression is allowed */
139	int	allow_tcp_forwarding; /* One of FORWARD_* */
140	int	allow_streamlocal_forwarding; /* One of FORWARD_* */
141	int	allow_agent_forwarding;
142	int	disable_forwarding;
143	u_int num_allow_users;
144	char   **allow_users;
145	u_int num_deny_users;
146	char   **deny_users;
147	u_int num_allow_groups;
148	char   **allow_groups;
149	u_int num_deny_groups;
150	char   **deny_groups;
151
152	u_int num_subsystems;
153	char   *subsystem_name[MAX_SUBSYSTEMS];
154	char   *subsystem_command[MAX_SUBSYSTEMS];
155	char   *subsystem_args[MAX_SUBSYSTEMS];
156
157	u_int num_accept_env;
158	char   **accept_env;
159	u_int num_setenv;
160	char   **setenv;
161
162	int	max_startups_begin;
163	int	max_startups_rate;
164	int	max_startups;
165	int	max_authtries;
166	int	max_sessions;
167	char   *banner;			/* SSH-2 banner message */
168	int	use_dns;
169	int	client_alive_interval;	/*
170					 * poke the client this often to
171					 * see if it's still there
172					 */
173	int	client_alive_count_max;	/*
174					 * If the client is unresponsive
175					 * for this many intervals above,
176					 * disconnect the session
177					 */
178
179	u_int	num_authkeys_files;	/* Files containing public keys */
180	char   **authorized_keys_files;
181
182	char   *adm_forced_command;
183
184	int	use_pam;		/* Enable auth via PAM */
185
186	int	permit_tun;
187
188	char   **permitted_opens;	/* May also be one of PERMITOPEN_* */
189	u_int   num_permitted_opens;
190	char   **permitted_listens; /* May also be one of PERMITOPEN_* */
191	u_int   num_permitted_listens;
192
193	char   *chroot_directory;
194	char   *revoked_keys_file;
195	char   *trusted_user_ca_keys;
196	char   *authorized_keys_command;
197	char   *authorized_keys_command_user;
198	char   *authorized_principals_file;
199	char   *authorized_principals_command;
200	char   *authorized_principals_command_user;
201
202	int64_t rekey_limit;
203	int	rekey_interval;
204
205	char   *version_addendum;	/* Appended to SSH banner */
206
207	u_int	num_auth_methods;
208	char   **auth_methods;
209
210	int	fingerprint_hash;
211	int	expose_userauth_info;
212	u_int64_t timing_secret;
213	int	use_blacklist;
214}       ServerOptions;
215
216/* Information about the incoming connection as used by Match */
217struct connection_info {
218	const char *user;
219	const char *host;	/* possibly resolved hostname */
220	const char *address; 	/* remote address */
221	const char *laddress;	/* local address */
222	int lport;		/* local port */
223	const char *rdomain;	/* routing domain if available */
224};
225
226
227/*
228 * These are string config options that must be copied between the
229 * Match sub-config and the main config, and must be sent from the
230 * privsep slave to the privsep master. We use a macro to ensure all
231 * the options are copied and the copies are done in the correct order.
232 *
233 * NB. an option must appear in servconf.c:copy_set_server_options() or
234 * COPY_MATCH_STRING_OPTS here but never both.
235 */
236#define COPY_MATCH_STRING_OPTS() do { \
237		M_CP_STROPT(banner); \
238		M_CP_STROPT(trusted_user_ca_keys); \
239		M_CP_STROPT(revoked_keys_file); \
240		M_CP_STROPT(authorized_keys_command); \
241		M_CP_STROPT(authorized_keys_command_user); \
242		M_CP_STROPT(authorized_principals_file); \
243		M_CP_STROPT(authorized_principals_command); \
244		M_CP_STROPT(authorized_principals_command_user); \
245		M_CP_STROPT(hostbased_key_types); \
246		M_CP_STROPT(pubkey_key_types); \
247		M_CP_STROPT(ca_sign_algorithms); \
248		M_CP_STROPT(routing_domain); \
249		M_CP_STROPT(permit_user_env_whitelist); \
250		M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \
251		M_CP_STRARRAYOPT(allow_users, num_allow_users); \
252		M_CP_STRARRAYOPT(deny_users, num_deny_users); \
253		M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \
254		M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \
255		M_CP_STRARRAYOPT(accept_env, num_accept_env); \
256		M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \
257		M_CP_STRARRAYOPT(permitted_opens, num_permitted_opens); \
258		M_CP_STRARRAYOPT(permitted_listens, num_permitted_listens); \
259	} while (0)
260
261struct connection_info *get_connection_info(int, int);
262void	 initialize_server_options(ServerOptions *);
263void	 fill_default_server_options(ServerOptions *);
264int	 process_server_config_line(ServerOptions *, char *, const char *, int,
265	     int *, struct connection_info *);
266void	 process_permitopen(struct ssh *ssh, ServerOptions *options);
267void	 load_server_config(const char *, struct sshbuf *);
268void	 parse_server_config(ServerOptions *, const char *, struct sshbuf *,
269	     struct connection_info *);
270void	 parse_server_match_config(ServerOptions *, struct connection_info *);
271int	 parse_server_match_testspec(struct connection_info *, char *);
272int	 server_match_spec_complete(struct connection_info *);
273void	 copy_set_server_options(ServerOptions *, ServerOptions *, int);
274void	 dump_config(ServerOptions *);
275char	*derelativise_path(const char *);
276void	 servconf_add_hostkey(const char *, const int,
277	    ServerOptions *, const char *path);
278void	 servconf_add_hostcert(const char *, const int,
279	    ServerOptions *, const char *path);
280
281#endif				/* SERVCONF_H */
282