1 /* $OpenBSD: servconf.h,v 1.144 2020/04/17 03:30:05 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 #include <openbsd-compat/sys-queue.h> 20 21 #define MAX_PORTS 256 /* Max # ports. */ 22 23 #define MAX_SUBSYSTEMS 256 /* Max # subsystems. */ 24 25 /* permit_root_login */ 26 #define PERMIT_NOT_SET -1 27 #define PERMIT_NO 0 28 #define PERMIT_FORCED_ONLY 1 29 #define PERMIT_NO_PASSWD 2 30 #define PERMIT_YES 3 31 32 /* use_privsep */ 33 #define PRIVSEP_OFF 0 34 #define PRIVSEP_ON 1 35 #define PRIVSEP_NOSANDBOX 2 36 37 /* PermitOpen */ 38 #define PERMITOPEN_ANY 0 39 #define PERMITOPEN_NONE -2 40 41 /* IgnoreRhosts */ 42 #define IGNORE_RHOSTS_NO 0 43 #define IGNORE_RHOSTS_YES 1 44 #define IGNORE_RHOSTS_SHOSTS 2 45 46 #define DEFAULT_AUTH_FAIL_MAX 6 /* Default for MaxAuthTries */ 47 #define DEFAULT_SESSIONS_MAX 10 /* Default for MaxSessions */ 48 49 /* Magic name for internal sftp-server */ 50 #define INTERNAL_SFTP_NAME "internal-sftp" 51 52 /* PubkeyAuthOptions flags */ 53 #define PUBKEYAUTH_TOUCH_REQUIRED 1 54 55 struct ssh; 56 struct fwd_perm_list; 57 58 /* 59 * Used to store addresses from ListenAddr directives. These may be 60 * incomplete, as they may specify addresses that need to be merged 61 * with any ports requested by ListenPort. 62 */ 63 struct queued_listenaddr { 64 char *addr; 65 int port; /* <=0 if unspecified */ 66 char *rdomain; 67 }; 68 69 /* Resolved listen addresses, grouped by optional routing domain */ 70 struct listenaddr { 71 char *rdomain; 72 struct addrinfo *addrs; 73 }; 74 75 typedef struct { 76 u_int num_ports; 77 u_int ports_from_cmdline; 78 int ports[MAX_PORTS]; /* Port number to listen on. */ 79 struct queued_listenaddr *queued_listen_addrs; 80 u_int num_queued_listens; 81 struct listenaddr *listen_addrs; 82 u_int num_listen_addrs; 83 int address_family; /* Address family used by the server. */ 84 85 char *routing_domain; /* Bind session to routing domain */ 86 87 char **host_key_files; /* Files containing host keys. */ 88 int *host_key_file_userprovided; /* Key was specified by user. */ 89 u_int num_host_key_files; /* Number of files for host keys. */ 90 char **host_cert_files; /* Files containing host certs. */ 91 u_int num_host_cert_files; /* Number of files for host certs. */ 92 93 char *host_key_agent; /* ssh-agent socket for host keys. */ 94 char *pid_file; /* Where to put our pid */ 95 int login_grace_time; /* Disconnect if no auth in this time 96 * (sec). */ 97 int permit_root_login; /* PERMIT_*, see above */ 98 int ignore_rhosts; /* Ignore .rhosts and .shosts. */ 99 int ignore_user_known_hosts; /* Ignore ~/.ssh/known_hosts 100 * for RhostsRsaAuth */ 101 int print_motd; /* If true, print /etc/motd. */ 102 int print_lastlog; /* If true, print lastlog */ 103 int x11_forwarding; /* If true, permit inet (spoofing) X11 fwd. */ 104 int x11_display_offset; /* What DISPLAY number to start 105 * searching at */ 106 int x11_use_localhost; /* If true, use localhost for fake X11 server. */ 107 char *xauth_location; /* Location of xauth program */ 108 int permit_tty; /* If false, deny pty allocation */ 109 int permit_user_rc; /* If false, deny ~/.ssh/rc execution */ 110 int strict_modes; /* If true, require string home dir modes. */ 111 int tcp_keep_alive; /* If true, set SO_KEEPALIVE. */ 112 int ip_qos_interactive; /* IP ToS/DSCP/class for interactive */ 113 int ip_qos_bulk; /* IP ToS/DSCP/class for bulk traffic */ 114 char *ciphers; /* Supported SSH2 ciphers. */ 115 char *macs; /* Supported SSH2 macs. */ 116 char *kex_algorithms; /* SSH2 kex methods in order of preference. */ 117 struct ForwardOptions fwd_opts; /* forwarding options */ 118 SyslogFacility log_facility; /* Facility for system logging. */ 119 LogLevel log_level; /* Level for system logging. */ 120 int hostbased_authentication; /* If true, permit ssh2 hostbased auth */ 121 int hostbased_uses_name_from_packet_only; /* experimental */ 122 char *hostbased_key_types; /* Key types allowed for hostbased */ 123 char *hostkeyalgorithms; /* SSH2 server key types */ 124 char *ca_sign_algorithms; /* Allowed CA signature algorithms */ 125 int pubkey_authentication; /* If true, permit ssh2 pubkey authentication. */ 126 char *pubkey_key_types; /* Key types allowed for public key */ 127 int pubkey_auth_options; /* -1 or mask of PUBKEYAUTH_* flags */ 128 int kerberos_authentication; /* If true, permit Kerberos 129 * authentication. */ 130 int kerberos_or_local_passwd; /* If true, permit kerberos 131 * and any other password 132 * authentication mechanism, 133 * such as SecurID or 134 * /etc/passwd */ 135 int kerberos_ticket_cleanup; /* If true, destroy ticket 136 * file on logout. */ 137 int kerberos_get_afs_token; /* If true, try to get AFS token if 138 * authenticated with Kerberos. */ 139 int gss_authentication; /* If true, permit GSSAPI authentication */ 140 int gss_cleanup_creds; /* If true, destroy cred cache on logout */ 141 int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */ 142 int password_authentication; /* If true, permit password 143 * authentication. */ 144 int kbd_interactive_authentication; /* If true, permit */ 145 int challenge_response_authentication; 146 int permit_empty_passwd; /* If false, do not permit empty 147 * passwords. */ 148 int permit_user_env; /* If true, read ~/.ssh/environment */ 149 char *permit_user_env_whitelist; /* pattern-list whitelist */ 150 int compression; /* If true, compression is allowed */ 151 int allow_tcp_forwarding; /* One of FORWARD_* */ 152 int allow_streamlocal_forwarding; /* One of FORWARD_* */ 153 int allow_agent_forwarding; 154 int disable_forwarding; 155 u_int num_allow_users; 156 char **allow_users; 157 u_int num_deny_users; 158 char **deny_users; 159 u_int num_allow_groups; 160 char **allow_groups; 161 u_int num_deny_groups; 162 char **deny_groups; 163 164 u_int num_subsystems; 165 char *subsystem_name[MAX_SUBSYSTEMS]; 166 char *subsystem_command[MAX_SUBSYSTEMS]; 167 char *subsystem_args[MAX_SUBSYSTEMS]; 168 169 u_int num_accept_env; 170 char **accept_env; 171 u_int num_setenv; 172 char **setenv; 173 174 int max_startups_begin; 175 int max_startups_rate; 176 int max_startups; 177 int max_authtries; 178 int max_sessions; 179 char *banner; /* SSH-2 banner message */ 180 int use_dns; 181 int client_alive_interval; /* 182 * poke the client this often to 183 * see if it's still there 184 */ 185 int client_alive_count_max; /* 186 * If the client is unresponsive 187 * for this many intervals above, 188 * disconnect the session 189 */ 190 191 u_int num_authkeys_files; /* Files containing public keys */ 192 char **authorized_keys_files; 193 194 char *adm_forced_command; 195 196 int use_pam; /* Enable auth via PAM */ 197 198 int permit_tun; 199 200 char **permitted_opens; /* May also be one of PERMITOPEN_* */ 201 u_int num_permitted_opens; 202 char **permitted_listens; /* May also be one of PERMITOPEN_* */ 203 u_int num_permitted_listens; 204 205 char *chroot_directory; 206 char *revoked_keys_file; 207 char *trusted_user_ca_keys; 208 char *authorized_keys_command; 209 char *authorized_keys_command_user; 210 char *authorized_principals_file; 211 char *authorized_principals_command; 212 char *authorized_principals_command_user; 213 214 int64_t rekey_limit; 215 int rekey_interval; 216 217 char *version_addendum; /* Appended to SSH banner */ 218 219 u_int num_auth_methods; 220 char **auth_methods; 221 222 int fingerprint_hash; 223 int expose_userauth_info; 224 u_int64_t timing_secret; 225 char *sk_provider; 226 } ServerOptions; 227 228 /* Information about the incoming connection as used by Match */ 229 struct connection_info { 230 const char *user; 231 const char *host; /* possibly resolved hostname */ 232 const char *address; /* remote address */ 233 const char *laddress; /* local address */ 234 int lport; /* local port */ 235 const char *rdomain; /* routing domain if available */ 236 int test; /* test mode, allow some attributes to be 237 * unspecified */ 238 }; 239 240 /* List of included files for re-exec from the parsed configuration */ 241 struct include_item { 242 char *selector; 243 char *filename; 244 struct sshbuf *contents; 245 TAILQ_ENTRY(include_item) entry; 246 }; 247 TAILQ_HEAD(include_list, include_item); 248 249 250 /* 251 * These are string config options that must be copied between the 252 * Match sub-config and the main config, and must be sent from the 253 * privsep slave to the privsep master. We use a macro to ensure all 254 * the options are copied and the copies are done in the correct order. 255 * 256 * NB. an option must appear in servconf.c:copy_set_server_options() or 257 * COPY_MATCH_STRING_OPTS here but never both. 258 */ 259 #define COPY_MATCH_STRING_OPTS() do { \ 260 M_CP_STROPT(banner); \ 261 M_CP_STROPT(trusted_user_ca_keys); \ 262 M_CP_STROPT(revoked_keys_file); \ 263 M_CP_STROPT(authorized_keys_command); \ 264 M_CP_STROPT(authorized_keys_command_user); \ 265 M_CP_STROPT(authorized_principals_file); \ 266 M_CP_STROPT(authorized_principals_command); \ 267 M_CP_STROPT(authorized_principals_command_user); \ 268 M_CP_STROPT(hostbased_key_types); \ 269 M_CP_STROPT(pubkey_key_types); \ 270 M_CP_STROPT(ca_sign_algorithms); \ 271 M_CP_STROPT(routing_domain); \ 272 M_CP_STROPT(permit_user_env_whitelist); \ 273 M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \ 274 M_CP_STRARRAYOPT(allow_users, num_allow_users); \ 275 M_CP_STRARRAYOPT(deny_users, num_deny_users); \ 276 M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \ 277 M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \ 278 M_CP_STRARRAYOPT(accept_env, num_accept_env); \ 279 M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \ 280 M_CP_STRARRAYOPT(permitted_opens, num_permitted_opens); \ 281 M_CP_STRARRAYOPT(permitted_listens, num_permitted_listens); \ 282 } while (0) 283 284 struct connection_info *get_connection_info(struct ssh *, int, int); 285 void initialize_server_options(ServerOptions *); 286 void fill_default_server_options(ServerOptions *); 287 int process_server_config_line(ServerOptions *, char *, const char *, int, 288 int *, struct connection_info *, struct include_list *includes); 289 void process_permitopen(struct ssh *ssh, ServerOptions *options); 290 void load_server_config(const char *, struct sshbuf *); 291 void parse_server_config(ServerOptions *, const char *, struct sshbuf *, 292 struct include_list *includes, struct connection_info *); 293 void parse_server_match_config(ServerOptions *, 294 struct include_list *includes, struct connection_info *); 295 int parse_server_match_testspec(struct connection_info *, char *); 296 int server_match_spec_complete(struct connection_info *); 297 void copy_set_server_options(ServerOptions *, ServerOptions *, int); 298 void dump_config(ServerOptions *); 299 char *derelativise_path(const char *); 300 void servconf_add_hostkey(const char *, const int, 301 ServerOptions *, const char *path, int); 302 void servconf_add_hostcert(const char *, const int, 303 ServerOptions *, const char *path); 304 305 #endif /* SERVCONF_H */ 306