xref: /freebsd/crypto/openssh/servconf.h (revision 6ae1554a5d9b318f8ad53ccc39fa5a961403da73)
1 /* $OpenBSD: servconf.h,v 1.112 2014/01/29 06:18:35 djm Exp $ */
2 /* $FreeBSD$ */
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 #define MAX_PORTS		256	/* Max # ports. */
21 
22 #define MAX_ALLOW_USERS		256	/* Max # users on allow list. */
23 #define MAX_DENY_USERS		256	/* Max # users on deny list. */
24 #define MAX_ALLOW_GROUPS	256	/* Max # groups on allow list. */
25 #define MAX_DENY_GROUPS		256	/* Max # groups on deny list. */
26 #define MAX_SUBSYSTEMS		256	/* Max # subsystems. */
27 #define MAX_HOSTKEYS		256	/* Max # hostkeys. */
28 #define MAX_HOSTCERTS		256	/* Max # host certificates. */
29 #define MAX_ACCEPT_ENV		256	/* Max # of env vars. */
30 #define MAX_MATCH_GROUPS	256	/* Max # of groups for Match. */
31 #define MAX_AUTHKEYS_FILES	256	/* Max # of authorized_keys files. */
32 #define MAX_AUTH_METHODS	256	/* Max # of AuthenticationMethods. */
33 
34 /* permit_root_login */
35 #define	PERMIT_NOT_SET		-1
36 #define	PERMIT_NO		0
37 #define	PERMIT_FORCED_ONLY	1
38 #define	PERMIT_NO_PASSWD	2
39 #define	PERMIT_YES		3
40 
41 /* use_privsep */
42 #define PRIVSEP_OFF		0
43 #define PRIVSEP_ON		1
44 #define PRIVSEP_NOSANDBOX	2
45 
46 /* AllowTCPForwarding */
47 #define FORWARD_DENY		0
48 #define FORWARD_REMOTE		(1)
49 #define FORWARD_LOCAL		(1<<1)
50 #define FORWARD_ALLOW		(FORWARD_REMOTE|FORWARD_LOCAL)
51 
52 #define DEFAULT_AUTH_FAIL_MAX	6	/* Default for MaxAuthTries */
53 #define DEFAULT_SESSIONS_MAX	10	/* Default for MaxSessions */
54 
55 /* Magic name for internal sftp-server */
56 #define INTERNAL_SFTP_NAME	"internal-sftp"
57 
58 typedef struct {
59 	u_int	num_ports;
60 	u_int	ports_from_cmdline;
61 	int	ports[MAX_PORTS];	/* Port number to listen on. */
62 	char   *listen_addr;		/* Address on which the server listens. */
63 	struct addrinfo *listen_addrs;	/* Addresses on which the server listens. */
64 	int     address_family;		/* Address family used by the server. */
65 	char   *host_key_files[MAX_HOSTKEYS];	/* Files containing host keys. */
66 	int     num_host_key_files;     /* Number of files for host keys. */
67 	char   *host_cert_files[MAX_HOSTCERTS];	/* Files containing host certs. */
68 	int     num_host_cert_files;     /* Number of files for host certs. */
69 	char   *host_key_agent;		 /* ssh-agent socket for host keys. */
70 	char   *pid_file;	/* Where to put our pid */
71 	int     server_key_bits;/* Size of the server key. */
72 	int     login_grace_time;	/* Disconnect if no auth in this time
73 					 * (sec). */
74 	int     key_regeneration_time;	/* Server key lifetime (seconds). */
75 	int     permit_root_login;	/* PERMIT_*, see above */
76 	int     ignore_rhosts;	/* Ignore .rhosts and .shosts. */
77 	int     ignore_user_known_hosts;	/* Ignore ~/.ssh/known_hosts
78 						 * for RhostsRsaAuth */
79 	int     print_motd;	/* If true, print /etc/motd. */
80 	int	print_lastlog;	/* If true, print lastlog */
81 	int     x11_forwarding;	/* If true, permit inet (spoofing) X11 fwd. */
82 	int     x11_display_offset;	/* What DISPLAY number to start
83 					 * searching at */
84 	int     x11_use_localhost;	/* If true, use localhost for fake X11 server. */
85 	char   *xauth_location;	/* Location of xauth program */
86 	int	permit_tty;	/* If false, deny pty allocation */
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 	int	protocol;	/* Supported protocol versions. */
95 	int     gateway_ports;	/* If true, allow remote connects to forwarded ports. */
96 	SyslogFacility log_facility;	/* Facility for system logging. */
97 	LogLevel log_level;	/* Level for system logging. */
98 	int     rhosts_rsa_authentication;	/* If true, permit rhosts RSA
99 						 * authentication. */
100 	int     hostbased_authentication;	/* If true, permit ssh2 hostbased auth */
101 	int     hostbased_uses_name_from_packet_only; /* experimental */
102 	int     rsa_authentication;	/* If true, permit RSA authentication. */
103 	int     pubkey_authentication;	/* If true, permit ssh2 pubkey authentication. */
104 	int     kerberos_authentication;	/* If true, permit Kerberos
105 						 * authentication. */
106 	int     kerberos_or_local_passwd;	/* If true, permit kerberos
107 						 * and any other password
108 						 * authentication mechanism,
109 						 * such as SecurID or
110 						 * /etc/passwd */
111 	int     kerberos_ticket_cleanup;	/* If true, destroy ticket
112 						 * file on logout. */
113 	int     kerberos_get_afs_token;		/* If true, try to get AFS token if
114 						 * authenticated with Kerberos. */
115 	int     gss_authentication;	/* If true, permit GSSAPI authentication */
116 	int     gss_cleanup_creds;	/* If true, destroy cred cache on logout */
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     use_login;	/* If true, login(1) is used */
125 	int     compression;	/* If true, compression is allowed */
126 	int	allow_tcp_forwarding; /* One of FORWARD_* */
127 	int	allow_agent_forwarding;
128 	u_int num_allow_users;
129 	char   *allow_users[MAX_ALLOW_USERS];
130 	u_int num_deny_users;
131 	char   *deny_users[MAX_DENY_USERS];
132 	u_int num_allow_groups;
133 	char   *allow_groups[MAX_ALLOW_GROUPS];
134 	u_int num_deny_groups;
135 	char   *deny_groups[MAX_DENY_GROUPS];
136 
137 	u_int num_subsystems;
138 	char   *subsystem_name[MAX_SUBSYSTEMS];
139 	char   *subsystem_command[MAX_SUBSYSTEMS];
140 	char   *subsystem_args[MAX_SUBSYSTEMS];
141 
142 	u_int num_accept_env;
143 	char   *accept_env[MAX_ACCEPT_ENV];
144 
145 	int	max_startups_begin;
146 	int	max_startups_rate;
147 	int	max_startups;
148 	int	max_authtries;
149 	int	max_sessions;
150 	char   *banner;			/* SSH-2 banner message */
151 	int	use_dns;
152 	int	client_alive_interval;	/*
153 					 * poke the client this often to
154 					 * see if it's still there
155 					 */
156 	int	client_alive_count_max;	/*
157 					 * If the client is unresponsive
158 					 * for this many intervals above,
159 					 * disconnect the session
160 					 */
161 
162 	u_int num_authkeys_files;	/* Files containing public keys */
163 	char   *authorized_keys_files[MAX_AUTHKEYS_FILES];
164 
165 	char   *adm_forced_command;
166 
167 	int	use_pam;		/* Enable auth via PAM */
168 
169 	int	permit_tun;
170 
171 	int	num_permitted_opens;
172 
173 	char   *chroot_directory;
174 	char   *revoked_keys_file;
175 	char   *trusted_user_ca_keys;
176 	char   *authorized_principals_file;
177 	char   *authorized_keys_command;
178 	char   *authorized_keys_command_user;
179 
180 	int64_t rekey_limit;
181 	int	rekey_interval;
182 
183 	char   *version_addendum;	/* Appended to SSH banner */
184 
185 	int	hpn_disabled;		/* Disable HPN functionality. */
186 	int	hpn_buffer_size;	/* Set HPN buffer size - default 2MB.*/
187 	int	tcp_rcv_buf_poll;	/* Poll TCP rcv window in autotuning
188 					 * kernels. */
189 	u_int	num_auth_methods;
190 	char   *auth_methods[MAX_AUTH_METHODS];
191 
192 #ifdef	NONE_CIPHER_ENABLED
193 	int	none_enabled;		/* Enable NONE cipher switch. */
194 #endif
195 }       ServerOptions;
196 
197 /* Information about the incoming connection as used by Match */
198 struct connection_info {
199 	const char *user;
200 	const char *host;	/* possibly resolved hostname */
201 	const char *address; 	/* remote address */
202 	const char *laddress;	/* local address */
203 	int lport;		/* local port */
204 };
205 
206 
207 /*
208  * These are string config options that must be copied between the
209  * Match sub-config and the main config, and must be sent from the
210  * privsep slave to the privsep master. We use a macro to ensure all
211  * the options are copied and the copies are done in the correct order.
212  *
213  * NB. an option must appear in servconf.c:copy_set_server_options() or
214  * COPY_MATCH_STRING_OPTS here but never both.
215  */
216 #define COPY_MATCH_STRING_OPTS() do { \
217 		M_CP_STROPT(banner); \
218 		M_CP_STROPT(trusted_user_ca_keys); \
219 		M_CP_STROPT(revoked_keys_file); \
220 		M_CP_STROPT(authorized_principals_file); \
221 		M_CP_STROPT(authorized_keys_command); \
222 		M_CP_STROPT(authorized_keys_command_user); \
223 		M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \
224 		M_CP_STRARRAYOPT(allow_users, num_allow_users); \
225 		M_CP_STRARRAYOPT(deny_users, num_deny_users); \
226 		M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \
227 		M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \
228 		M_CP_STRARRAYOPT(accept_env, num_accept_env); \
229 		M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \
230 	} while (0)
231 
232 struct connection_info *get_connection_info(int, int);
233 void	 initialize_server_options(ServerOptions *);
234 void	 fill_default_server_options(ServerOptions *);
235 int	 process_server_config_line(ServerOptions *, char *, const char *, int,
236 	     int *, struct connection_info *);
237 void	 load_server_config(const char *, Buffer *);
238 void	 parse_server_config(ServerOptions *, const char *, Buffer *,
239 	     struct connection_info *);
240 void	 parse_server_match_config(ServerOptions *, struct connection_info *);
241 int	 parse_server_match_testspec(struct connection_info *, char *);
242 int	 server_match_spec_complete(struct connection_info *);
243 void	 copy_set_server_options(ServerOptions *, ServerOptions *, int);
244 void	 dump_config(ServerOptions *);
245 char	*derelativise_path(const char *);
246 
247 #endif				/* SERVCONF_H */
248