1 /* $OpenBSD: servconf.h,v 1.126 2017/10/02 19:33:20 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 #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 /* PermitOpen */ 52 #define PERMITOPEN_ANY 0 53 #define PERMITOPEN_NONE -2 54 55 #define DEFAULT_AUTH_FAIL_MAX 6 /* Default for MaxAuthTries */ 56 #define DEFAULT_SESSIONS_MAX 10 /* Default for MaxSessions */ 57 58 /* Magic name for internal sftp-server */ 59 #define INTERNAL_SFTP_NAME "internal-sftp" 60 61 struct ssh; 62 struct fwd_perm_list; 63 64 typedef struct { 65 u_int num_ports; 66 u_int ports_from_cmdline; 67 int ports[MAX_PORTS]; /* Port number to listen on. */ 68 u_int num_queued_listens; 69 char **queued_listen_addrs; 70 int *queued_listen_ports; 71 struct addrinfo *listen_addrs; /* Addresses on which the server listens. */ 72 int address_family; /* Address family used by the server. */ 73 char *host_key_files[MAX_HOSTKEYS]; /* Files containing host keys. */ 74 int num_host_key_files; /* Number of files for host keys. */ 75 char *host_cert_files[MAX_HOSTCERTS]; /* Files containing host certs. */ 76 int num_host_cert_files; /* Number of files for host certs. */ 77 char *host_key_agent; /* ssh-agent socket for host keys. */ 78 char *pid_file; /* Where to put our pid */ 79 int login_grace_time; /* Disconnect if no auth in this time 80 * (sec). */ 81 int permit_root_login; /* PERMIT_*, see above */ 82 int ignore_rhosts; /* Ignore .rhosts and .shosts. */ 83 int ignore_user_known_hosts; /* Ignore ~/.ssh/known_hosts 84 * for RhostsRsaAuth */ 85 int print_motd; /* If true, print /etc/motd. */ 86 int print_lastlog; /* If true, print lastlog */ 87 int x11_forwarding; /* If true, permit inet (spoofing) X11 fwd. */ 88 int x11_display_offset; /* What DISPLAY number to start 89 * searching at */ 90 int x11_use_localhost; /* If true, use localhost for fake X11 server. */ 91 char *xauth_location; /* Location of xauth program */ 92 int permit_tty; /* If false, deny pty allocation */ 93 int permit_user_rc; /* If false, deny ~/.ssh/rc execution */ 94 int strict_modes; /* If true, require string home dir modes. */ 95 int tcp_keep_alive; /* If true, set SO_KEEPALIVE. */ 96 int ip_qos_interactive; /* IP ToS/DSCP/class for interactive */ 97 int ip_qos_bulk; /* IP ToS/DSCP/class for bulk traffic */ 98 char *ciphers; /* Supported SSH2 ciphers. */ 99 char *macs; /* Supported SSH2 macs. */ 100 char *kex_algorithms; /* SSH2 kex methods in order of preference. */ 101 struct ForwardOptions fwd_opts; /* forwarding options */ 102 SyslogFacility log_facility; /* Facility for system logging. */ 103 LogLevel log_level; /* Level for system logging. */ 104 int hostbased_authentication; /* If true, permit ssh2 hostbased auth */ 105 int hostbased_uses_name_from_packet_only; /* experimental */ 106 char *hostbased_key_types; /* Key types allowed for hostbased */ 107 char *hostkeyalgorithms; /* SSH2 server key types */ 108 int pubkey_authentication; /* If true, permit ssh2 pubkey authentication. */ 109 char *pubkey_key_types; /* Key types allowed for public key */ 110 int kerberos_authentication; /* If true, permit Kerberos 111 * authentication. */ 112 int kerberos_or_local_passwd; /* If true, permit kerberos 113 * and any other password 114 * authentication mechanism, 115 * such as SecurID or 116 * /etc/passwd */ 117 int kerberos_ticket_cleanup; /* If true, destroy ticket 118 * file on logout. */ 119 int kerberos_get_afs_token; /* If true, try to get AFS token if 120 * authenticated with Kerberos. */ 121 int gss_authentication; /* If true, permit GSSAPI authentication */ 122 int gss_cleanup_creds; /* If true, destroy cred cache on logout */ 123 int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */ 124 int password_authentication; /* If true, permit password 125 * authentication. */ 126 int kbd_interactive_authentication; /* If true, permit */ 127 int challenge_response_authentication; 128 int permit_empty_passwd; /* If false, do not permit empty 129 * passwords. */ 130 int permit_user_env; /* If true, read ~/.ssh/environment */ 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 int disable_forwarding; 136 u_int num_allow_users; 137 char *allow_users[MAX_ALLOW_USERS]; 138 u_int num_deny_users; 139 char *deny_users[MAX_DENY_USERS]; 140 u_int num_allow_groups; 141 char *allow_groups[MAX_ALLOW_GROUPS]; 142 u_int num_deny_groups; 143 char *deny_groups[MAX_DENY_GROUPS]; 144 145 u_int num_subsystems; 146 char *subsystem_name[MAX_SUBSYSTEMS]; 147 char *subsystem_command[MAX_SUBSYSTEMS]; 148 char *subsystem_args[MAX_SUBSYSTEMS]; 149 150 u_int num_accept_env; 151 char *accept_env[MAX_ACCEPT_ENV]; 152 153 int max_startups_begin; 154 int max_startups_rate; 155 int max_startups; 156 int max_authtries; 157 int max_sessions; 158 char *banner; /* SSH-2 banner message */ 159 int use_dns; 160 int client_alive_interval; /* 161 * poke the client this often to 162 * see if it's still there 163 */ 164 int client_alive_count_max; /* 165 * If the client is unresponsive 166 * for this many intervals above, 167 * disconnect the session 168 */ 169 170 u_int num_authkeys_files; /* Files containing public keys */ 171 char *authorized_keys_files[MAX_AUTHKEYS_FILES]; 172 173 char *adm_forced_command; 174 175 int use_pam; /* Enable auth via PAM */ 176 177 int permit_tun; 178 179 char **permitted_opens; 180 u_int num_permitted_opens; /* May also be one of PERMITOPEN_* */ 181 182 char *chroot_directory; 183 char *revoked_keys_file; 184 char *trusted_user_ca_keys; 185 char *authorized_keys_command; 186 char *authorized_keys_command_user; 187 char *authorized_principals_file; 188 char *authorized_principals_command; 189 char *authorized_principals_command_user; 190 191 int64_t rekey_limit; 192 int rekey_interval; 193 194 char *version_addendum; /* Appended to SSH banner */ 195 196 u_int num_auth_methods; 197 char *auth_methods[MAX_AUTH_METHODS]; 198 199 int fingerprint_hash; 200 int expose_userauth_info; 201 } ServerOptions; 202 203 /* Information about the incoming connection as used by Match */ 204 struct connection_info { 205 const char *user; 206 const char *host; /* possibly resolved hostname */ 207 const char *address; /* remote address */ 208 const char *laddress; /* local address */ 209 int lport; /* local port */ 210 }; 211 212 213 /* 214 * These are string config options that must be copied between the 215 * Match sub-config and the main config, and must be sent from the 216 * privsep slave to the privsep master. We use a macro to ensure all 217 * the options are copied and the copies are done in the correct order. 218 * 219 * NB. an option must appear in servconf.c:copy_set_server_options() or 220 * COPY_MATCH_STRING_OPTS here but never both. 221 */ 222 #define COPY_MATCH_STRING_OPTS() do { \ 223 M_CP_STROPT(banner); \ 224 M_CP_STROPT(trusted_user_ca_keys); \ 225 M_CP_STROPT(revoked_keys_file); \ 226 M_CP_STROPT(authorized_keys_command); \ 227 M_CP_STROPT(authorized_keys_command_user); \ 228 M_CP_STROPT(authorized_principals_file); \ 229 M_CP_STROPT(authorized_principals_command); \ 230 M_CP_STROPT(authorized_principals_command_user); \ 231 M_CP_STROPT(hostbased_key_types); \ 232 M_CP_STROPT(pubkey_key_types); \ 233 M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \ 234 M_CP_STRARRAYOPT(allow_users, num_allow_users); \ 235 M_CP_STRARRAYOPT(deny_users, num_deny_users); \ 236 M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \ 237 M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \ 238 M_CP_STRARRAYOPT(accept_env, num_accept_env); \ 239 M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \ 240 M_CP_STRARRAYOPT_ALLOC(permitted_opens, num_permitted_opens); \ 241 } while (0) 242 243 struct connection_info *get_connection_info(int, int); 244 void initialize_server_options(ServerOptions *); 245 void fill_default_server_options(ServerOptions *); 246 int process_server_config_line(ServerOptions *, char *, const char *, int, 247 int *, struct connection_info *); 248 void process_permitopen(struct ssh *ssh, ServerOptions *options); 249 void load_server_config(const char *, Buffer *); 250 void parse_server_config(ServerOptions *, const char *, Buffer *, 251 struct connection_info *); 252 void parse_server_match_config(ServerOptions *, struct connection_info *); 253 int parse_server_match_testspec(struct connection_info *, char *); 254 int server_match_spec_complete(struct connection_info *); 255 void copy_set_server_options(ServerOptions *, ServerOptions *, int); 256 void dump_config(ServerOptions *); 257 char *derelativise_path(const char *); 258 259 #endif /* SERVCONF_H */ 260