1 /* $OpenBSD: servconf.h,v 1.143 2020/01/31 22:42:45 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 <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 #define DEFAULT_AUTH_FAIL_MAX 6 /* Default for MaxAuthTries */ 42 #define DEFAULT_SESSIONS_MAX 10 /* Default for MaxSessions */ 43 44 /* Magic name for internal sftp-server */ 45 #define INTERNAL_SFTP_NAME "internal-sftp" 46 47 /* PubkeyAuthOptions flags */ 48 #define PUBKEYAUTH_TOUCH_REQUIRED 1 49 50 struct ssh; 51 struct 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 */ 58 struct 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 */ 65 struct listenaddr { 66 char *rdomain; 67 struct addrinfo *addrs; 68 }; 69 70 typedef 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_user_known_hosts; /* Ignore ~/.ssh/known_hosts 95 * for RhostsRsaAuth */ 96 int print_motd; /* If true, print /etc/motd. */ 97 int print_lastlog; /* If true, print lastlog */ 98 int x11_forwarding; /* If true, permit inet (spoofing) X11 fwd. */ 99 int x11_display_offset; /* What DISPLAY number to start 100 * searching at */ 101 int x11_use_localhost; /* If true, use localhost for fake X11 server. */ 102 char *xauth_location; /* Location of xauth program */ 103 int permit_tty; /* If false, deny pty allocation */ 104 int permit_user_rc; /* If false, deny ~/.ssh/rc execution */ 105 int strict_modes; /* If true, require string home dir modes. */ 106 int tcp_keep_alive; /* If true, set SO_KEEPALIVE. */ 107 int ip_qos_interactive; /* IP ToS/DSCP/class for interactive */ 108 int ip_qos_bulk; /* IP ToS/DSCP/class for bulk traffic */ 109 char *ciphers; /* Supported SSH2 ciphers. */ 110 char *macs; /* Supported SSH2 macs. */ 111 char *kex_algorithms; /* SSH2 kex methods in order of preference. */ 112 struct ForwardOptions fwd_opts; /* forwarding options */ 113 SyslogFacility log_facility; /* Facility for system logging. */ 114 LogLevel log_level; /* Level for system logging. */ 115 int hostbased_authentication; /* If true, permit ssh2 hostbased auth */ 116 int hostbased_uses_name_from_packet_only; /* experimental */ 117 char *hostbased_key_types; /* Key types allowed for hostbased */ 118 char *hostkeyalgorithms; /* SSH2 server key types */ 119 char *ca_sign_algorithms; /* Allowed CA signature algorithms */ 120 int pubkey_authentication; /* If true, permit ssh2 pubkey authentication. */ 121 char *pubkey_key_types; /* Key types allowed for public key */ 122 int pubkey_auth_options; /* -1 or mask of PUBKEYAUTH_* flags */ 123 int kerberos_authentication; /* If true, permit Kerberos 124 * authentication. */ 125 int kerberos_or_local_passwd; /* If true, permit kerberos 126 * and any other password 127 * authentication mechanism, 128 * such as SecurID or 129 * /etc/passwd */ 130 int kerberos_ticket_cleanup; /* If true, destroy ticket 131 * file on logout. */ 132 int kerberos_get_afs_token; /* If true, try to get AFS token if 133 * authenticated with Kerberos. */ 134 int gss_authentication; /* If true, permit GSSAPI authentication */ 135 int gss_cleanup_creds; /* If true, destroy cred cache on logout */ 136 int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */ 137 int password_authentication; /* If true, permit password 138 * authentication. */ 139 int kbd_interactive_authentication; /* If true, permit */ 140 int challenge_response_authentication; 141 int permit_empty_passwd; /* If false, do not permit empty 142 * passwords. */ 143 int permit_user_env; /* If true, read ~/.ssh/environment */ 144 char *permit_user_env_whitelist; /* pattern-list whitelist */ 145 int compression; /* If true, compression is allowed */ 146 int allow_tcp_forwarding; /* One of FORWARD_* */ 147 int allow_streamlocal_forwarding; /* One of FORWARD_* */ 148 int allow_agent_forwarding; 149 int disable_forwarding; 150 u_int num_allow_users; 151 char **allow_users; 152 u_int num_deny_users; 153 char **deny_users; 154 u_int num_allow_groups; 155 char **allow_groups; 156 u_int num_deny_groups; 157 char **deny_groups; 158 159 u_int num_subsystems; 160 char *subsystem_name[MAX_SUBSYSTEMS]; 161 char *subsystem_command[MAX_SUBSYSTEMS]; 162 char *subsystem_args[MAX_SUBSYSTEMS]; 163 164 u_int num_accept_env; 165 char **accept_env; 166 u_int num_setenv; 167 char **setenv; 168 169 int max_startups_begin; 170 int max_startups_rate; 171 int max_startups; 172 int max_authtries; 173 int max_sessions; 174 char *banner; /* SSH-2 banner message */ 175 int use_dns; 176 int client_alive_interval; /* 177 * poke the client this often to 178 * see if it's still there 179 */ 180 int client_alive_count_max; /* 181 * If the client is unresponsive 182 * for this many intervals above, 183 * disconnect the session 184 */ 185 186 u_int num_authkeys_files; /* Files containing public keys */ 187 char **authorized_keys_files; 188 189 char *adm_forced_command; 190 191 int permit_tun; 192 193 char **permitted_opens; /* May also be one of PERMITOPEN_* */ 194 u_int num_permitted_opens; 195 char **permitted_listens; /* May also be one of PERMITOPEN_* */ 196 u_int num_permitted_listens; 197 198 char *chroot_directory; 199 char *revoked_keys_file; 200 char *trusted_user_ca_keys; 201 char *authorized_keys_command; 202 char *authorized_keys_command_user; 203 char *authorized_principals_file; 204 char *authorized_principals_command; 205 char *authorized_principals_command_user; 206 207 int64_t rekey_limit; 208 int rekey_interval; 209 210 char *version_addendum; /* Appended to SSH banner */ 211 212 u_int num_auth_methods; 213 char **auth_methods; 214 215 int fingerprint_hash; 216 int expose_userauth_info; 217 u_int64_t timing_secret; 218 char *sk_provider; 219 } ServerOptions; 220 221 /* Information about the incoming connection as used by Match */ 222 struct connection_info { 223 const char *user; 224 const char *host; /* possibly resolved hostname */ 225 const char *address; /* remote address */ 226 const char *laddress; /* local address */ 227 int lport; /* local port */ 228 const char *rdomain; /* routing domain if available */ 229 int test; /* test mode, allow some attributes to be 230 * unspecified */ 231 }; 232 233 /* List of included files for re-exec from the parsed configuration */ 234 struct include_item { 235 char *selector; 236 char *filename; 237 struct sshbuf *contents; 238 TAILQ_ENTRY(include_item) entry; 239 }; 240 TAILQ_HEAD(include_list, include_item); 241 242 243 /* 244 * These are string config options that must be copied between the 245 * Match sub-config and the main config, and must be sent from the 246 * privsep slave to the privsep master. We use a macro to ensure all 247 * the options are copied and the copies are done in the correct order. 248 * 249 * NB. an option must appear in servconf.c:copy_set_server_options() or 250 * COPY_MATCH_STRING_OPTS here but never both. 251 */ 252 #define COPY_MATCH_STRING_OPTS() do { \ 253 M_CP_STROPT(banner); \ 254 M_CP_STROPT(trusted_user_ca_keys); \ 255 M_CP_STROPT(revoked_keys_file); \ 256 M_CP_STROPT(authorized_keys_command); \ 257 M_CP_STROPT(authorized_keys_command_user); \ 258 M_CP_STROPT(authorized_principals_file); \ 259 M_CP_STROPT(authorized_principals_command); \ 260 M_CP_STROPT(authorized_principals_command_user); \ 261 M_CP_STROPT(hostbased_key_types); \ 262 M_CP_STROPT(pubkey_key_types); \ 263 M_CP_STROPT(ca_sign_algorithms); \ 264 M_CP_STROPT(routing_domain); \ 265 M_CP_STROPT(permit_user_env_whitelist); \ 266 M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \ 267 M_CP_STRARRAYOPT(allow_users, num_allow_users); \ 268 M_CP_STRARRAYOPT(deny_users, num_deny_users); \ 269 M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \ 270 M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \ 271 M_CP_STRARRAYOPT(accept_env, num_accept_env); \ 272 M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \ 273 M_CP_STRARRAYOPT(permitted_opens, num_permitted_opens); \ 274 M_CP_STRARRAYOPT(permitted_listens, num_permitted_listens); \ 275 } while (0) 276 277 struct connection_info *get_connection_info(struct ssh *, int, int); 278 void initialize_server_options(ServerOptions *); 279 void fill_default_server_options(ServerOptions *); 280 int process_server_config_line(ServerOptions *, char *, const char *, int, 281 int *, struct connection_info *, struct include_list *includes); 282 void process_permitopen(struct ssh *ssh, ServerOptions *options); 283 void load_server_config(const char *, struct sshbuf *); 284 void parse_server_config(ServerOptions *, const char *, struct sshbuf *, 285 struct include_list *includes, struct connection_info *); 286 void parse_server_match_config(ServerOptions *, 287 struct include_list *includes, struct connection_info *); 288 int parse_server_match_testspec(struct connection_info *, char *); 289 int server_match_spec_complete(struct connection_info *); 290 void copy_set_server_options(ServerOptions *, ServerOptions *, int); 291 void dump_config(ServerOptions *); 292 char *derelativise_path(const char *); 293 void servconf_add_hostkey(const char *, const int, 294 ServerOptions *, const char *path, int); 295 void servconf_add_hostcert(const char *, const int, 296 ServerOptions *, const char *path); 297 298 #endif /* SERVCONF_H */ 299