xref: /freebsd/crypto/openssh/servconf.h (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /* $OpenBSD: servconf.h,v 1.120 2015/07/10 06:21:53 markus 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 
57 typedef 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     server_key_bits;/* Size of the server key. */
73 	int     login_grace_time;	/* Disconnect if no auth in this time
74 					 * (sec). */
75 	int     key_regeneration_time;	/* Server key lifetime (seconds). */
76 	int     permit_root_login;	/* PERMIT_*, see above */
77 	int     ignore_rhosts;	/* Ignore .rhosts and .shosts. */
78 	int     ignore_user_known_hosts;	/* Ignore ~/.ssh/known_hosts
79 						 * for RhostsRsaAuth */
80 	int     print_motd;	/* If true, print /etc/motd. */
81 	int	print_lastlog;	/* If true, print lastlog */
82 	int     x11_forwarding;	/* If true, permit inet (spoofing) X11 fwd. */
83 	int     x11_display_offset;	/* What DISPLAY number to start
84 					 * searching at */
85 	int     x11_use_localhost;	/* If true, use localhost for fake X11 server. */
86 	char   *xauth_location;	/* Location of xauth program */
87 	int	permit_tty;	/* If false, deny pty allocation */
88 	int	permit_user_rc;	/* If false, deny ~/.ssh/rc execution */
89 	int     strict_modes;	/* If true, require string home dir modes. */
90 	int     tcp_keep_alive;	/* If true, set SO_KEEPALIVE. */
91 	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
92 	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
93 	char   *ciphers;	/* Supported SSH2 ciphers. */
94 	char   *macs;		/* Supported SSH2 macs. */
95 	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
96 	int	protocol;	/* Supported protocol versions. */
97 	struct ForwardOptions fwd_opts;	/* forwarding options */
98 	SyslogFacility log_facility;	/* Facility for system logging. */
99 	LogLevel log_level;	/* Level for system logging. */
100 	int     rhosts_rsa_authentication;	/* If true, permit rhosts RSA
101 						 * authentication. */
102 	int     hostbased_authentication;	/* If true, permit ssh2 hostbased auth */
103 	int     hostbased_uses_name_from_packet_only; /* experimental */
104 	char   *hostbased_key_types;	/* Key types allowed for hostbased */
105 	char   *hostkeyalgorithms;	/* SSH2 server key types */
106 	int     rsa_authentication;	/* If true, permit RSA authentication. */
107 	int     pubkey_authentication;	/* If true, permit ssh2 pubkey authentication. */
108 	char   *pubkey_key_types;	/* Key types allowed for public key */
109 	int     kerberos_authentication;	/* If true, permit Kerberos
110 						 * authentication. */
111 	int     kerberos_or_local_passwd;	/* If true, permit kerberos
112 						 * and any other password
113 						 * authentication mechanism,
114 						 * such as SecurID or
115 						 * /etc/passwd */
116 	int     kerberos_ticket_cleanup;	/* If true, destroy ticket
117 						 * file on logout. */
118 	int     kerberos_get_afs_token;		/* If true, try to get AFS token if
119 						 * authenticated with Kerberos. */
120 	int     gss_authentication;	/* If true, permit GSSAPI authentication */
121 	int     gss_cleanup_creds;	/* If true, destroy cred cache on logout */
122 	int     gss_strict_acceptor;	/* If true, restrict the GSSAPI acceptor name */
123 	int     password_authentication;	/* If true, permit password
124 						 * authentication. */
125 	int     kbd_interactive_authentication;	/* If true, permit */
126 	int     challenge_response_authentication;
127 	int     permit_empty_passwd;	/* If false, do not permit empty
128 					 * passwords. */
129 	int     permit_user_env;	/* If true, read ~/.ssh/environment */
130 	int     use_login;	/* If true, login(1) is used */
131 	int     compression;	/* If true, compression is allowed */
132 	int	allow_tcp_forwarding; /* One of FORWARD_* */
133 	int	allow_streamlocal_forwarding; /* One of FORWARD_* */
134 	int	allow_agent_forwarding;
135 	u_int num_allow_users;
136 	char   *allow_users[MAX_ALLOW_USERS];
137 	u_int num_deny_users;
138 	char   *deny_users[MAX_DENY_USERS];
139 	u_int num_allow_groups;
140 	char   *allow_groups[MAX_ALLOW_GROUPS];
141 	u_int num_deny_groups;
142 	char   *deny_groups[MAX_DENY_GROUPS];
143 
144 	u_int num_subsystems;
145 	char   *subsystem_name[MAX_SUBSYSTEMS];
146 	char   *subsystem_command[MAX_SUBSYSTEMS];
147 	char   *subsystem_args[MAX_SUBSYSTEMS];
148 
149 	u_int num_accept_env;
150 	char   *accept_env[MAX_ACCEPT_ENV];
151 
152 	int	max_startups_begin;
153 	int	max_startups_rate;
154 	int	max_startups;
155 	int	max_authtries;
156 	int	max_sessions;
157 	char   *banner;			/* SSH-2 banner message */
158 	int	use_dns;
159 	int	client_alive_interval;	/*
160 					 * poke the client this often to
161 					 * see if it's still there
162 					 */
163 	int	client_alive_count_max;	/*
164 					 * If the client is unresponsive
165 					 * for this many intervals above,
166 					 * disconnect the session
167 					 */
168 
169 	u_int num_authkeys_files;	/* Files containing public keys */
170 	char   *authorized_keys_files[MAX_AUTHKEYS_FILES];
171 
172 	char   *adm_forced_command;
173 
174 	int	use_pam;		/* Enable auth via PAM */
175 
176 	int	permit_tun;
177 
178 	int	num_permitted_opens;
179 
180 	char   *chroot_directory;
181 	char   *revoked_keys_file;
182 	char   *trusted_user_ca_keys;
183 	char   *authorized_keys_command;
184 	char   *authorized_keys_command_user;
185 	char   *authorized_principals_file;
186 	char   *authorized_principals_command;
187 	char   *authorized_principals_command_user;
188 
189 	int64_t rekey_limit;
190 	int	rekey_interval;
191 
192 	char   *version_addendum;	/* Appended to SSH banner */
193 
194 	u_int	num_auth_methods;
195 	char   *auth_methods[MAX_AUTH_METHODS];
196 
197 	int	fingerprint_hash;
198 	int	use_blacklist;
199 }       ServerOptions;
200 
201 /* Information about the incoming connection as used by Match */
202 struct connection_info {
203 	const char *user;
204 	const char *host;	/* possibly resolved hostname */
205 	const char *address; 	/* remote address */
206 	const char *laddress;	/* local address */
207 	int lport;		/* local port */
208 };
209 
210 
211 /*
212  * These are string config options that must be copied between the
213  * Match sub-config and the main config, and must be sent from the
214  * privsep slave to the privsep master. We use a macro to ensure all
215  * the options are copied and the copies are done in the correct order.
216  *
217  * NB. an option must appear in servconf.c:copy_set_server_options() or
218  * COPY_MATCH_STRING_OPTS here but never both.
219  */
220 #define COPY_MATCH_STRING_OPTS() do { \
221 		M_CP_STROPT(banner); \
222 		M_CP_STROPT(trusted_user_ca_keys); \
223 		M_CP_STROPT(revoked_keys_file); \
224 		M_CP_STROPT(authorized_keys_command); \
225 		M_CP_STROPT(authorized_keys_command_user); \
226 		M_CP_STROPT(authorized_principals_file); \
227 		M_CP_STROPT(authorized_principals_command); \
228 		M_CP_STROPT(authorized_principals_command_user); \
229 		M_CP_STROPT(hostbased_key_types); \
230 		M_CP_STROPT(pubkey_key_types); \
231 		M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \
232 		M_CP_STRARRAYOPT(allow_users, num_allow_users); \
233 		M_CP_STRARRAYOPT(deny_users, num_deny_users); \
234 		M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \
235 		M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \
236 		M_CP_STRARRAYOPT(accept_env, num_accept_env); \
237 		M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \
238 	} while (0)
239 
240 struct connection_info *get_connection_info(int, int);
241 void	 initialize_server_options(ServerOptions *);
242 void	 fill_default_server_options(ServerOptions *);
243 int	 process_server_config_line(ServerOptions *, char *, const char *, int,
244 	     int *, struct connection_info *);
245 void	 load_server_config(const char *, Buffer *);
246 void	 parse_server_config(ServerOptions *, const char *, Buffer *,
247 	     struct connection_info *);
248 void	 parse_server_match_config(ServerOptions *, struct connection_info *);
249 int	 parse_server_match_testspec(struct connection_info *, char *);
250 int	 server_match_spec_complete(struct connection_info *);
251 void	 copy_set_server_options(ServerOptions *, ServerOptions *, int);
252 void	 dump_config(ServerOptions *);
253 char	*derelativise_path(const char *);
254 
255 #endif				/* SERVCONF_H */
256