servconf.h revision 323134
1/* $OpenBSD: servconf.h,v 1.123 2016/11/30 03:00:05 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_ALLOW_USERS		256	/* Max # users on allow list. */
22#define MAX_DENY_USERS		256	/* Max # users on deny list. */
23#define MAX_ALLOW_GROUPS	256	/* Max # groups on allow list. */
24#define MAX_DENY_GROUPS		256	/* Max # groups on deny list. */
25#define MAX_SUBSYSTEMS		256	/* Max # subsystems. */
26#define MAX_HOSTKEYS		256	/* Max # hostkeys. */
27#define MAX_HOSTCERTS		256	/* Max # host certificates. */
28#define MAX_ACCEPT_ENV		256	/* Max # of env vars. */
29#define MAX_MATCH_GROUPS	256	/* Max # of groups for Match. */
30#define MAX_AUTHKEYS_FILES	256	/* Max # of authorized_keys files. */
31#define MAX_AUTH_METHODS	256	/* Max # of AuthenticationMethods. */
32
33/* permit_root_login */
34#define	PERMIT_NOT_SET		-1
35#define	PERMIT_NO		0
36#define	PERMIT_FORCED_ONLY	1
37#define	PERMIT_NO_PASSWD	2
38#define	PERMIT_YES		3
39
40/* use_privsep */
41#define PRIVSEP_OFF		0
42#define PRIVSEP_ON		1
43#define PRIVSEP_NOSANDBOX	2
44
45/* AllowTCPForwarding */
46#define FORWARD_DENY		0
47#define FORWARD_REMOTE		(1)
48#define FORWARD_LOCAL		(1<<1)
49#define FORWARD_ALLOW		(FORWARD_REMOTE|FORWARD_LOCAL)
50
51#define DEFAULT_AUTH_FAIL_MAX	6	/* Default for MaxAuthTries */
52#define DEFAULT_SESSIONS_MAX	10	/* Default for MaxSessions */
53
54/* Magic name for internal sftp-server */
55#define INTERNAL_SFTP_NAME	"internal-sftp"
56
57typedef struct {
58	u_int	num_ports;
59	u_int	ports_from_cmdline;
60	int	ports[MAX_PORTS];	/* Port number to listen on. */
61	u_int	num_queued_listens;
62	char   **queued_listen_addrs;
63	int    *queued_listen_ports;
64	struct addrinfo *listen_addrs;	/* Addresses on which the server listens. */
65	int     address_family;		/* Address family used by the server. */
66	char   *host_key_files[MAX_HOSTKEYS];	/* Files containing host keys. */
67	int     num_host_key_files;     /* Number of files for host keys. */
68	char   *host_cert_files[MAX_HOSTCERTS];	/* Files containing host certs. */
69	int     num_host_cert_files;     /* Number of files for host certs. */
70	char   *host_key_agent;		 /* ssh-agent socket for host keys. */
71	char   *pid_file;	/* Where to put our pid */
72	int     login_grace_time;	/* Disconnect if no auth in this time
73					 * (sec). */
74	int     permit_root_login;	/* PERMIT_*, see above */
75	int     ignore_rhosts;	/* Ignore .rhosts and .shosts. */
76	int     ignore_user_known_hosts;	/* Ignore ~/.ssh/known_hosts
77						 * for RhostsRsaAuth */
78	int     print_motd;	/* If true, print /etc/motd. */
79	int	print_lastlog;	/* If true, print lastlog */
80	int     x11_forwarding;	/* If true, permit inet (spoofing) X11 fwd. */
81	int     x11_display_offset;	/* What DISPLAY number to start
82					 * searching at */
83	int     x11_use_localhost;	/* If true, use localhost for fake X11 server. */
84	char   *xauth_location;	/* Location of xauth program */
85	int	permit_tty;	/* If false, deny pty allocation */
86	int	permit_user_rc;	/* If false, deny ~/.ssh/rc execution */
87	int     strict_modes;	/* If true, require string home dir modes. */
88	int     tcp_keep_alive;	/* If true, set SO_KEEPALIVE. */
89	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
90	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
91	char   *ciphers;	/* Supported SSH2 ciphers. */
92	char   *macs;		/* Supported SSH2 macs. */
93	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
94	struct ForwardOptions fwd_opts;	/* forwarding options */
95	SyslogFacility log_facility;	/* Facility for system logging. */
96	LogLevel log_level;	/* Level for system logging. */
97	int     hostbased_authentication;	/* If true, permit ssh2 hostbased auth */
98	int     hostbased_uses_name_from_packet_only; /* experimental */
99	char   *hostbased_key_types;	/* Key types allowed for hostbased */
100	char   *hostkeyalgorithms;	/* SSH2 server key types */
101	int     pubkey_authentication;	/* If true, permit ssh2 pubkey authentication. */
102	char   *pubkey_key_types;	/* Key types allowed for public key */
103	int     kerberos_authentication;	/* If true, permit Kerberos
104						 * authentication. */
105	int     kerberos_or_local_passwd;	/* If true, permit kerberos
106						 * and any other password
107						 * authentication mechanism,
108						 * such as SecurID or
109						 * /etc/passwd */
110	int     kerberos_ticket_cleanup;	/* If true, destroy ticket
111						 * file on logout. */
112	int     kerberos_get_afs_token;		/* If true, try to get AFS token if
113						 * authenticated with Kerberos. */
114	int     gss_authentication;	/* If true, permit GSSAPI authentication */
115	int     gss_cleanup_creds;	/* If true, destroy cred cache on logout */
116	int     gss_strict_acceptor;	/* If true, restrict the GSSAPI acceptor name */
117	int     password_authentication;	/* If true, permit password
118						 * authentication. */
119	int     kbd_interactive_authentication;	/* If true, permit */
120	int     challenge_response_authentication;
121	int     permit_empty_passwd;	/* If false, do not permit empty
122					 * passwords. */
123	int     permit_user_env;	/* If true, read ~/.ssh/environment */
124	int     compression;	/* If true, compression is allowed */
125	int	allow_tcp_forwarding; /* One of FORWARD_* */
126	int	allow_streamlocal_forwarding; /* One of FORWARD_* */
127	int	allow_agent_forwarding;
128	int	disable_forwarding;
129	u_int num_allow_users;
130	char   *allow_users[MAX_ALLOW_USERS];
131	u_int num_deny_users;
132	char   *deny_users[MAX_DENY_USERS];
133	u_int num_allow_groups;
134	char   *allow_groups[MAX_ALLOW_GROUPS];
135	u_int num_deny_groups;
136	char   *deny_groups[MAX_DENY_GROUPS];
137
138	u_int num_subsystems;
139	char   *subsystem_name[MAX_SUBSYSTEMS];
140	char   *subsystem_command[MAX_SUBSYSTEMS];
141	char   *subsystem_args[MAX_SUBSYSTEMS];
142
143	u_int num_accept_env;
144	char   *accept_env[MAX_ACCEPT_ENV];
145
146	int	max_startups_begin;
147	int	max_startups_rate;
148	int	max_startups;
149	int	max_authtries;
150	int	max_sessions;
151	char   *banner;			/* SSH-2 banner message */
152	int	use_dns;
153	int	client_alive_interval;	/*
154					 * poke the client this often to
155					 * see if it's still there
156					 */
157	int	client_alive_count_max;	/*
158					 * If the client is unresponsive
159					 * for this many intervals above,
160					 * disconnect the session
161					 */
162
163	u_int num_authkeys_files;	/* Files containing public keys */
164	char   *authorized_keys_files[MAX_AUTHKEYS_FILES];
165
166	char   *adm_forced_command;
167
168	int	use_pam;		/* Enable auth via PAM */
169
170	int	permit_tun;
171
172	int	num_permitted_opens;
173
174	char   *chroot_directory;
175	char   *revoked_keys_file;
176	char   *trusted_user_ca_keys;
177	char   *authorized_keys_command;
178	char   *authorized_keys_command_user;
179	char   *authorized_principals_file;
180	char   *authorized_principals_command;
181	char   *authorized_principals_command_user;
182
183	int64_t rekey_limit;
184	int	rekey_interval;
185
186	char   *version_addendum;	/* Appended to SSH banner */
187
188	u_int	num_auth_methods;
189	char   *auth_methods[MAX_AUTH_METHODS];
190
191	int	fingerprint_hash;
192	int	use_blacklist;
193}       ServerOptions;
194
195/* Information about the incoming connection as used by Match */
196struct connection_info {
197	const char *user;
198	const char *host;	/* possibly resolved hostname */
199	const char *address; 	/* remote address */
200	const char *laddress;	/* local address */
201	int lport;		/* local port */
202};
203
204
205/*
206 * These are string config options that must be copied between the
207 * Match sub-config and the main config, and must be sent from the
208 * privsep slave to the privsep master. We use a macro to ensure all
209 * the options are copied and the copies are done in the correct order.
210 *
211 * NB. an option must appear in servconf.c:copy_set_server_options() or
212 * COPY_MATCH_STRING_OPTS here but never both.
213 */
214#define COPY_MATCH_STRING_OPTS() do { \
215		M_CP_STROPT(banner); \
216		M_CP_STROPT(trusted_user_ca_keys); \
217		M_CP_STROPT(revoked_keys_file); \
218		M_CP_STROPT(authorized_keys_command); \
219		M_CP_STROPT(authorized_keys_command_user); \
220		M_CP_STROPT(authorized_principals_file); \
221		M_CP_STROPT(authorized_principals_command); \
222		M_CP_STROPT(authorized_principals_command_user); \
223		M_CP_STROPT(hostbased_key_types); \
224		M_CP_STROPT(pubkey_key_types); \
225		M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \
226		M_CP_STRARRAYOPT(allow_users, num_allow_users); \
227		M_CP_STRARRAYOPT(deny_users, num_deny_users); \
228		M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \
229		M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \
230		M_CP_STRARRAYOPT(accept_env, num_accept_env); \
231		M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \
232	} while (0)
233
234struct connection_info *get_connection_info(int, int);
235void	 initialize_server_options(ServerOptions *);
236void	 fill_default_server_options(ServerOptions *);
237int	 process_server_config_line(ServerOptions *, char *, const char *, int,
238	     int *, struct connection_info *);
239void	 load_server_config(const char *, Buffer *);
240void	 parse_server_config(ServerOptions *, const char *, Buffer *,
241	     struct connection_info *);
242void	 parse_server_match_config(ServerOptions *, struct connection_info *);
243int	 parse_server_match_testspec(struct connection_info *, char *);
244int	 server_match_spec_complete(struct connection_info *);
245void	 copy_set_server_options(ServerOptions *, ServerOptions *, int);
246void	 dump_config(ServerOptions *);
247char	*derelativise_path(const char *);
248
249#endif				/* SERVCONF_H */
250