servconf.h revision 1.19 
1/*	$NetBSD: servconf.h,v 1.19 2019/04/20 17:16:40 christos Exp $	*/
2/* $OpenBSD: servconf.h,v 1.139 2019/01/19 21:37:48 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/* PermitOpen */
41#define PERMITOPEN_ANY		0
42#define PERMITOPEN_NONE		-2
43
44#define DEFAULT_AUTH_FAIL_MAX	6	/* Default for MaxAuthTries */
45#define DEFAULT_SESSIONS_MAX	10	/* Default for MaxSessions */
46
47/* Magic name for internal sftp-server */
48#define INTERNAL_SFTP_NAME	"internal-sftp"
49
50struct ssh;
51struct fwd_perm_list;
52
53/*
54 * Used to store addresses from ListenAddr directives. These may be
55 * incomplete, as they may specify addresses that need to be merged
56 * with any ports requested by ListenPort.
57 */
58struct queued_listenaddr {
59	char *addr;
60	int port; /* <=0 if unspecified */
61	char *rdomain;
62};
63
64/* Resolved listen addresses, grouped by optional routing domain */
65struct listenaddr {
66	char *rdomain;
67	struct addrinfo *addrs;
68};
69
70typedef struct {
71	u_int	num_ports;
72	u_int	ports_from_cmdline;
73	int	ports[MAX_PORTS];	/* Port number to listen on. */
74	struct queued_listenaddr *queued_listen_addrs;
75	u_int	num_queued_listens;
76	struct listenaddr *listen_addrs;
77	u_int	num_listen_addrs;
78	int	address_family;		/* Address family used by the server. */
79
80	char	*routing_domain;	/* Bind session to routing domain */
81
82	char   **host_key_files;	/* Files containing host keys. */
83	int	*host_key_file_userprovided; /* Key was specified by user. */
84	u_int	num_host_key_files;     /* Number of files for host keys. */
85	char   **host_cert_files;	/* Files containing host certs. */
86	u_int	num_host_cert_files;	/* Number of files for host certs. */
87
88	char   *host_key_agent;		/* ssh-agent socket for host keys. */
89	char   *pid_file;		/* Where to put our pid */
90	int     login_grace_time;	/* Disconnect if no auth in this time
91					 * (sec). */
92	int     permit_root_login;	/* PERMIT_*, see above */
93	int     ignore_rhosts;	/* Ignore .rhosts and .shosts. */
94	int     ignore_root_rhosts;	/* Ignore .rhosts and .shosts for root;
95					   defaults to ignore_rhosts if not
96					   given. */
97	int     ignore_user_known_hosts;	/* Ignore ~/.ssh/known_hosts
98						 * for RhostsRsaAuth */
99	int     print_motd;	/* If true, print /etc/motd. */
100	int	print_lastlog;	/* If true, print lastlog */
101	int     x11_forwarding;	/* If true, permit inet (spoofing) X11 fwd. */
102	int     x11_display_offset;	/* What DISPLAY number to start
103					 * searching at */
104	int     x11_use_localhost;	/* If true, use localhost for fake X11 server. */
105	char   *xauth_location;	/* Location of xauth program */
106	int	permit_tty;	/* If false, deny pty allocation */
107	int	permit_user_rc;	/* If false, deny ~/.ssh/rc execution */
108	int     strict_modes;	/* If true, require string home dir modes. */
109	int     tcp_keep_alive;	/* If true, set SO_KEEPALIVE. */
110	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
111	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
112	char   *ciphers;	/* Supported SSH2 ciphers. */
113	char   *macs;		/* Supported SSH2 macs. */
114	char   *kex_algorithms;	/* SSH2 kex methods in order of preference. */
115	struct ForwardOptions fwd_opts;	/* forwarding options */
116	SyslogFacility log_facility;	/* Facility for system logging. */
117	LogLevel log_level;	/* Level for system logging. */
118	int     hostbased_authentication;	/* If true, permit ssh2 hostbased auth */
119	int     hostbased_uses_name_from_packet_only; /* experimental */
120	char   *hostbased_key_types;	/* Key types allowed for hostbased */
121	char   *hostkeyalgorithms;	/* SSH2 server key types */
122	char   *ca_sign_algorithms;	/* Allowed CA signature algorithms */
123	int     pubkey_authentication;	/* If true, permit ssh2 pubkey authentication. */
124	char   *pubkey_key_types;	/* Key types allowed for public key */
125	int     kerberos_authentication;	/* If true, permit Kerberos
126						 * authentication. */
127	int     kerberos_or_local_passwd;	/* If true, permit kerberos
128						 * and any other password
129						 * authentication mechanism,
130						 * such as SecurID or
131						 * /etc/passwd */
132	int     kerberos_ticket_cleanup;	/* If true, destroy ticket
133						 * file on logout. */
134	int	kerberos_tgt_passing;		/* If true, permit Kerberos TGT
135						 * passing. */
136	int     kerberos_get_afs_token;		/* If true, try to get AFS token if
137						 * authenticated with Kerberos. */
138#ifdef AFS
139	int     afs_token_passing;      /* If true, permit AFS token passing. */
140#endif
141	int     gss_authentication;	/* If true, permit GSSAPI authentication */
142	int     gss_cleanup_creds;	/* If true, destroy cred cache on logout */
143	int     gss_strict_acceptor;	/* If true, restrict the GSSAPI acceptor name */
144	int     password_authentication;	/* If true, permit password
145						 * authentication. */
146	int     kbd_interactive_authentication;	/* If true, permit */
147	int     challenge_response_authentication;
148	int     permit_empty_passwd;	/* If false, do not permit empty
149					 * passwords. */
150	int     permit_user_env;	/* If true, read ~/.ssh/environment */
151	char   *permit_user_env_whitelist; /* pattern-list whitelist */
152	int     compression;	/* If true, compression is allowed */
153	int	allow_tcp_forwarding; /* One of FORWARD_* */
154	int	allow_streamlocal_forwarding; /* One of FORWARD_* */
155	int	allow_agent_forwarding;
156	int	disable_forwarding;
157	u_int num_allow_users;
158	char   **allow_users;
159	u_int num_deny_users;
160	char   **deny_users;
161	u_int num_allow_groups;
162	char   **allow_groups;
163	u_int num_deny_groups;
164	char   **deny_groups;
165
166	u_int num_subsystems;
167	char   *subsystem_name[MAX_SUBSYSTEMS];
168	char   *subsystem_command[MAX_SUBSYSTEMS];
169	char   *subsystem_args[MAX_SUBSYSTEMS];
170
171	u_int num_accept_env;
172	char   **accept_env;
173	u_int num_setenv;
174	char   **setenv;
175
176	int	max_startups_begin;
177	int	max_startups_rate;
178	int	max_startups;
179	int	max_authtries;
180	int	max_sessions;
181	char   *banner;			/* SSH-2 banner message */
182	int	use_dns;
183	int	client_alive_interval;	/*
184					 * poke the client this often to
185					 * see if it's still there
186					 */
187	int	client_alive_count_max;	/*
188					 * If the client is unresponsive
189					 * for this many intervals above,
190					 * disconnect the session
191					 */
192
193	u_int	num_authkeys_files;	/* Files containing public keys */
194	char   **authorized_keys_files;
195
196	int	use_pam;		/* Enable auth via PAM */
197	int     none_enabled;           /* enable NONE cipher switch */
198	int     tcp_rcv_buf_poll;       /* poll tcp rcv window in autotuning kernels*/
199	int	hpn_disabled;		/* disable hpn functionality. false by default */
200	int	hpn_buffer_size;	/* set the hpn buffer size - default 3MB */
201
202	char   *adm_forced_command;
203
204	int	permit_tun;
205#ifdef WITH_LDAP_PUBKEY
206        ldap_opt_t lpk;
207#endif
208
209	char   **permitted_opens;	/* May also be one of PERMITOPEN_* */
210	u_int   num_permitted_opens;
211	char   **permitted_listens; /* May also be one of PERMITOPEN_* */
212	u_int   num_permitted_listens;
213
214	char   *chroot_directory;
215	char   *revoked_keys_file;
216	char   *trusted_user_ca_keys;
217	char   *authorized_keys_command;
218	char   *authorized_keys_command_user;
219	char   *authorized_principals_file;
220	char   *authorized_principals_command;
221	char   *authorized_principals_command_user;
222
223	int64_t rekey_limit;
224	int	rekey_interval;
225
226	char   *version_addendum;	/* Appended to SSH banner */
227
228	u_int	num_auth_methods;
229	char   **auth_methods;
230
231	int	fingerprint_hash;
232	int	expose_userauth_info;
233	u_int64_t timing_secret;
234}       ServerOptions;
235
236/* Information about the incoming connection as used by Match */
237struct connection_info {
238	const char *user;
239	const char *host;	/* possibly resolved hostname */
240	const char *address; 	/* remote address */
241	const char *laddress;	/* local address */
242	int lport;		/* local port */
243	const char *rdomain;	/* routing domain if available */
244};
245
246
247/*
248 * These are string config options that must be copied between the
249 * Match sub-config and the main config, and must be sent from the
250 * privsep slave to the privsep master. We use a macro to ensure all
251 * the options are copied and the copies are done in the correct order.
252 *
253 * NB. an option must appear in servconf.c:copy_set_server_options() or
254 * COPY_MATCH_STRING_OPTS here but never both.
255 */
256#define COPY_MATCH_STRING_OPTS() do { \
257		M_CP_STROPT(banner); \
258		M_CP_STROPT(trusted_user_ca_keys); \
259		M_CP_STROPT(revoked_keys_file); \
260		M_CP_STROPT(authorized_keys_command); \
261		M_CP_STROPT(authorized_keys_command_user); \
262		M_CP_STROPT(authorized_principals_file); \
263		M_CP_STROPT(authorized_principals_command); \
264		M_CP_STROPT(authorized_principals_command_user); \
265		M_CP_STROPT(hostbased_key_types); \
266		M_CP_STROPT(pubkey_key_types); \
267		M_CP_STROPT(ca_sign_algorithms); \
268		M_CP_STROPT(routing_domain); \
269		M_CP_STROPT(permit_user_env_whitelist); \
270		M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \
271		M_CP_STRARRAYOPT(allow_users, num_allow_users); \
272		M_CP_STRARRAYOPT(deny_users, num_deny_users); \
273		M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \
274		M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \
275		M_CP_STRARRAYOPT(accept_env, num_accept_env); \
276		M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \
277		M_CP_STRARRAYOPT(permitted_opens, num_permitted_opens); \
278		M_CP_STRARRAYOPT(permitted_listens, num_permitted_listens); \
279	} while (0)
280
281struct connection_info *get_connection_info(struct ssh *, int, int);
282void	 initialize_server_options(ServerOptions *);
283void	 fill_default_server_options(ServerOptions *);
284int	 process_server_config_line(ServerOptions *, char *, const char *, int,
285	     int *, struct connection_info *);
286void	 process_permitopen(struct ssh *ssh, ServerOptions *options);
287void	 load_server_config(const char *, struct sshbuf *);
288void	 parse_server_config(ServerOptions *, const char *, struct sshbuf *,
289	     struct connection_info *);
290void	 parse_server_match_config(ServerOptions *, struct connection_info *);
291int	 parse_server_match_testspec(struct connection_info *, char *);
292int	 server_match_spec_complete(struct connection_info *);
293void	 copy_set_server_options(ServerOptions *, ServerOptions *, int);
294void	 dump_config(ServerOptions *);
295char	*derelativise_path(const char *);
296void	 servconf_add_hostkey(const char *, const int,
297	    ServerOptions *, const char *path, int);
298void	 servconf_add_hostcert(const char *, const int,
299	    ServerOptions *, const char *path);
300
301#endif				/* SERVCONF_H */
302