1 /* $NetBSD: servconf.h,v 1.34 2026/04/08 18:58:41 christos Exp $ */ 2 /* $OpenBSD: servconf.h,v 1.176 2026/03/03 09:57:25 dtucker Exp $ */ 3 4 /* 5 * Author: Tatu Ylonen <ylo (at) cs.hut.fi> 6 * Copyright (c) 1995 Tatu Ylonen <ylo (at) 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 #include <sys/queue.h> 25 26 #define MAX_PORTS 256 /* Max # ports. */ 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 /* PermitOpen */ 36 #define PERMITOPEN_ANY 0 37 #define PERMITOPEN_NONE -2 38 39 /* IgnoreRhosts */ 40 #define IGNORE_RHOSTS_NO 0 41 #define IGNORE_RHOSTS_YES 1 42 #define IGNORE_RHOSTS_SHOSTS 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 50 /* PubkeyAuthOptions flags */ 51 #define PUBKEYAUTH_TOUCH_REQUIRED (1) 52 #define PUBKEYAUTH_VERIFY_REQUIRED (1<<1) 53 54 struct ssh; 55 56 /* 57 * Used to store addresses from ListenAddr directives. These may be 58 * incomplete, as they may specify addresses that need to be merged 59 * with any ports requested by ListenPort. 60 */ 61 struct queued_listenaddr { 62 char *addr; 63 int port; /* <=0 if unspecified */ 64 char *rdomain; 65 }; 66 67 /* Resolved listen addresses, grouped by optional routing domain */ 68 struct listenaddr { 69 char *rdomain; 70 struct addrinfo *addrs; 71 }; 72 73 #define PER_SOURCE_PENALTY_OVERFLOW_DENY_ALL 1 74 #define PER_SOURCE_PENALTY_OVERFLOW_PERMISSIVE 2 75 struct per_source_penalty { 76 int enabled; 77 int max_sources4; 78 int max_sources6; 79 int overflow_mode; 80 int overflow_mode6; 81 double penalty_crash; 82 double penalty_grace; 83 double penalty_authfail; 84 double penalty_invaliduser; 85 double penalty_noauth; 86 double penalty_refuseconnection; 87 double penalty_max; 88 double penalty_min; 89 }; 90 91 typedef struct { 92 u_int num_ports; 93 u_int ports_from_cmdline; 94 int ports[MAX_PORTS]; /* Port number to listen on. */ 95 struct queued_listenaddr *queued_listen_addrs; 96 u_int num_queued_listens; 97 struct listenaddr *listen_addrs; 98 u_int num_listen_addrs; 99 int address_family; /* Address family used by the server. */ 100 101 char *routing_domain; /* Bind session to routing domain */ 102 103 char **host_key_files; /* Files containing host keys. */ 104 int *host_key_file_userprovided; /* Key was specified by user. */ 105 u_int num_host_key_files; /* Number of files for host keys. */ 106 char **host_cert_files; /* Files containing host certs. */ 107 u_int num_host_cert_files; /* Number of files for host certs. */ 108 109 char *host_key_agent; /* ssh-agent socket for host keys. */ 110 char *pid_file; /* Where to put our pid */ 111 char *moduli_file; /* moduli file for DH-GEX */ 112 int login_grace_time; /* Disconnect if no auth in this time 113 * (sec). */ 114 int permit_root_login; /* PERMIT_*, see above */ 115 int ignore_rhosts; /* Ignore .rhosts and .shosts. */ 116 int ignore_root_rhosts; /* Ignore .rhosts and .shosts for root; 117 defaults to ignore_rhosts if not 118 given. */ 119 int ignore_user_known_hosts; /* Ignore ~/.ssh/known_hosts 120 * for RhostsRsaAuth */ 121 int print_motd; /* If true, print /etc/motd. */ 122 int print_lastlog; /* If true, print lastlog */ 123 int x11_forwarding; /* If true, permit inet (spoofing) X11 fwd. */ 124 int x11_display_offset; /* What DISPLAY number to start 125 * searching at */ 126 int x11_use_localhost; /* If true, use localhost for fake X11 server. */ 127 char *xauth_location; /* Location of xauth program */ 128 int permit_tty; /* If false, deny pty allocation */ 129 int permit_user_rc; /* If false, deny ~/.ssh/rc execution */ 130 int strict_modes; /* If true, require string home dir modes. */ 131 int tcp_keep_alive; /* If true, set SO_KEEPALIVE. */ 132 int ip_qos_interactive; /* IP ToS/DSCP/class for interactive */ 133 int ip_qos_bulk; /* IP ToS/DSCP/class for bulk traffic */ 134 char *ciphers; /* Supported SSH2 ciphers. */ 135 char *macs; /* Supported SSH2 macs. */ 136 char *kex_algorithms; /* SSH2 kex methods in order of preference. */ 137 struct ForwardOptions fwd_opts; /* forwarding options */ 138 SyslogFacility log_facility; /* Facility for system logging. */ 139 LogLevel log_level; /* Level for system logging. */ 140 u_int num_log_verbose; /* Verbose log overrides */ 141 char **log_verbose; 142 int hostbased_authentication; /* If true, permit ssh2 hostbased auth */ 143 int hostbased_uses_name_from_packet_only; /* experimental */ 144 char *hostbased_accepted_algos; /* Algos allowed for hostbased */ 145 char *hostkeyalgorithms; /* SSH2 server key types */ 146 char *ca_sign_algorithms; /* Allowed CA signature algorithms */ 147 int pubkey_authentication; /* If true, permit ssh2 pubkey authentication. */ 148 char *pubkey_accepted_algos; /* Signature algos allowed for pubkey */ 149 int pubkey_auth_options; /* -1 or mask of PUBKEYAUTH_* flags */ 150 int kerberos_authentication; /* If true, permit Kerberos 151 * authentication. */ 152 int kerberos_or_local_passwd; /* If true, permit kerberos 153 * and any other password 154 * authentication mechanism, 155 * such as SecurID or 156 * /etc/passwd */ 157 int kerberos_ticket_cleanup; /* If true, destroy ticket 158 * file on logout. */ 159 int kerberos_tgt_passing; /* If true, permit Kerberos TGT 160 * passing. */ 161 int kerberos_get_afs_token; /* If true, try to get AFS token if 162 * authenticated with Kerberos. */ 163 #ifdef AFS 164 int afs_token_passing; /* If true, permit AFS token passing. */ 165 #endif 166 int gss_authentication; /* If true, permit GSSAPI authentication */ 167 int gss_cleanup_creds; /* If true, destroy cred cache on logout */ 168 int gss_deleg_creds; /* If true, accept delegated GSS credentials */ 169 int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */ 170 int password_authentication; /* If true, permit password 171 * authentication. */ 172 int kbd_interactive_authentication; /* If true, permit */ 173 int permit_empty_passwd; /* If false, do not permit empty 174 * passwords. */ 175 int permit_user_env; /* If true, read ~/.ssh/environment */ 176 char *permit_user_env_allowlist; /* pattern-list of allowed env names */ 177 int compression; /* If true, compression is allowed */ 178 int allow_tcp_forwarding; /* One of FORWARD_* */ 179 int allow_streamlocal_forwarding; /* One of FORWARD_* */ 180 int allow_agent_forwarding; 181 int disable_forwarding; 182 u_int num_allow_users; 183 char **allow_users; 184 u_int num_deny_users; 185 char **deny_users; 186 u_int num_allow_groups; 187 char **allow_groups; 188 u_int num_deny_groups; 189 char **deny_groups; 190 191 u_int num_subsystems; 192 char **subsystem_name; 193 char **subsystem_command; 194 char **subsystem_args; 195 196 u_int num_accept_env; 197 char **accept_env; 198 u_int num_setenv; 199 char **setenv; 200 201 int max_startups_begin; 202 int max_startups_rate; 203 int max_startups; 204 int per_source_max_startups; 205 int per_source_masklen_ipv4; 206 int per_source_masklen_ipv6; 207 char *per_source_penalty_exempt; 208 struct per_source_penalty per_source_penalty; 209 int max_authtries; 210 int max_sessions; 211 char *banner; /* SSH-2 banner message */ 212 int use_dns; 213 int client_alive_interval; /* 214 * poke the client this often to 215 * see if it's still there 216 */ 217 int client_alive_count_max; /* 218 * If the client is unresponsive 219 * for this many intervals above, 220 * disconnect the session 221 */ 222 223 u_int num_authkeys_files; /* Files containing public keys */ 224 char **authorized_keys_files; 225 226 int use_pam; /* Enable auth via PAM */ 227 char *pam_service_name; 228 int none_enabled; /* enable NONE cipher switch */ 229 int tcp_rcv_buf_poll; /* poll tcp rcv window in autotuning kernels*/ 230 int hpn_disabled; /* disable hpn functionality. false by default */ 231 int hpn_buffer_size; /* set the hpn buffer size - default 3MB */ 232 233 char *adm_forced_command; 234 235 int permit_tun; 236 #ifdef WITH_LDAP_PUBKEY 237 ldap_opt_t lpk; 238 #endif 239 240 char **permitted_opens; /* May also be one of PERMITOPEN_* */ 241 u_int num_permitted_opens; 242 char **permitted_listens; /* May also be one of PERMITOPEN_* */ 243 u_int num_permitted_listens; 244 245 char *chroot_directory; 246 uint num_revoked_keys_files; 247 char **revoked_keys_files; 248 char *trusted_user_ca_keys; 249 char *authorized_keys_command; 250 char *authorized_keys_command_user; 251 char *authorized_principals_file; 252 char *authorized_principals_command; 253 char *authorized_principals_command_user; 254 255 int64_t rekey_limit; 256 int rekey_interval; 257 258 char *version_addendum; /* Appended to SSH banner */ 259 260 u_int num_auth_methods; 261 char **auth_methods; 262 263 int fingerprint_hash; 264 int expose_userauth_info; 265 uint64_t timing_secret; 266 char *sk_provider; 267 int required_rsa_size; /* minimum size of RSA keys */ 268 269 char **channel_timeouts; /* inactivity timeout by channel type */ 270 u_int num_channel_timeouts; 271 272 int unused_connection_timeout; 273 274 char *sshd_session_path; 275 char *sshd_auth_path; 276 277 int refuse_connection; 278 } ServerOptions; 279 280 /* Information about the incoming connection as used by Match */ 281 struct connection_info { 282 const char *user; 283 int user_invalid; 284 const char *host; /* possibly resolved hostname */ 285 const char *address; /* remote address */ 286 const char *laddress; /* local address */ 287 int lport; /* local port */ 288 const char *rdomain; /* routing domain if available */ 289 int test; /* test mode, allow some attributes to be 290 * unspecified */ 291 }; 292 293 /* List of included files for re-exec from the parsed configuration */ 294 struct include_item { 295 char *selector; 296 char *filename; 297 struct sshbuf *contents; 298 TAILQ_ENTRY(include_item) entry; 299 }; 300 TAILQ_HEAD(include_list, include_item); 301 302 303 /* 304 * These are string config options that must be copied between the 305 * Match sub-config and the main config, and must be sent from the 306 * privsep child to the privsep master. We use a macro to ensure all 307 * the options are copied and the copies are done in the correct order. 308 * 309 * NB. an option must appear in servconf.c:copy_set_server_options() or 310 * COPY_MATCH_STRING_OPTS here but never both. 311 */ 312 #define COPY_MATCH_STRING_OPTS() do { \ 313 M_CP_STROPT(banner); \ 314 M_CP_STROPT(trusted_user_ca_keys); \ 315 M_CP_STROPT(authorized_keys_command); \ 316 M_CP_STROPT(authorized_keys_command_user); \ 317 M_CP_STROPT(authorized_principals_file); \ 318 M_CP_STROPT(authorized_principals_command); \ 319 M_CP_STROPT(authorized_principals_command_user); \ 320 M_CP_STROPT(hostbased_accepted_algos); \ 321 M_CP_STROPT(pubkey_accepted_algos); \ 322 M_CP_STROPT(ca_sign_algorithms); \ 323 M_CP_STROPT(routing_domain); \ 324 M_CP_STROPT(permit_user_env_allowlist); \ 325 M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files, 1);\ 326 M_CP_STRARRAYOPT(revoked_keys_files, \ 327 num_revoked_keys_files, 1); \ 328 M_CP_STRARRAYOPT(allow_users, num_allow_users, 1); \ 329 M_CP_STRARRAYOPT(deny_users, num_deny_users, 1); \ 330 M_CP_STRARRAYOPT(allow_groups, num_allow_groups, 1); \ 331 M_CP_STRARRAYOPT(deny_groups, num_deny_groups, 1); \ 332 M_CP_STRARRAYOPT(accept_env, num_accept_env, 1); \ 333 M_CP_STRARRAYOPT(setenv, num_setenv, 1); \ 334 M_CP_STRARRAYOPT(auth_methods, num_auth_methods, 1); \ 335 M_CP_STRARRAYOPT(permitted_opens, num_permitted_opens, 1); \ 336 M_CP_STRARRAYOPT(permitted_listens, num_permitted_listens, 1); \ 337 M_CP_STRARRAYOPT(channel_timeouts, num_channel_timeouts, 1); \ 338 M_CP_STRARRAYOPT(log_verbose, num_log_verbose, 1); \ 339 /* Note: don't clobber num_subsystems until all copied */ \ 340 M_CP_STRARRAYOPT(subsystem_name, num_subsystems, 0); \ 341 M_CP_STRARRAYOPT(subsystem_command, num_subsystems, 0); \ 342 M_CP_STRARRAYOPT(subsystem_args, num_subsystems, 1); \ 343 } while (0) 344 345 void initialize_server_options(ServerOptions *); 346 void fill_default_server_options(ServerOptions *); 347 int process_server_config_line(ServerOptions *, char *, const char *, int, 348 int *, struct connection_info *, struct include_list *includes); 349 void load_server_config(const char *, struct sshbuf *); 350 void parse_server_config(ServerOptions *, const char *, struct sshbuf *, 351 struct include_list *includes, struct connection_info *, int); 352 void parse_server_match_config(ServerOptions *, 353 struct include_list *includes, struct connection_info *); 354 int parse_server_match_testspec(struct connection_info *, char *); 355 void servconf_merge_subsystems(ServerOptions *, ServerOptions *); 356 void copy_set_server_options(ServerOptions *, ServerOptions *, int); 357 void dump_config(ServerOptions *); 358 char *derelativise_path(const char *); 359 void servconf_add_hostkey(const char *, const int, 360 ServerOptions *, const char *path, int); 361 void servconf_add_hostcert(const char *, const int, 362 ServerOptions *, const char *path); 363 364 #endif /* SERVCONF_H */ 365
Indexes created Sat Jun 20 00:25:23 UTC 2026