/* $OpenBSD: servconf.h,v 1.155 2021/07/02 05:11:21 dtucker Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland * All rights reserved * Definitions for server configuration data and for the functions reading it. * * As far as I am concerned, the code I have written for this software * can be used freely for any purpose. Any derived versions of this * software must be clearly marked as such, and if the derived work is * incompatible with the protocol description in the RFC file, it must be * called by a name other than "ssh" or "Secure Shell". */ #ifndef SERVCONF_H #define SERVCONF_H #include #define MAX_PORTS 256 /* Max # ports. */ #define MAX_SUBSYSTEMS 256 /* Max # subsystems. */ /* permit_root_login */ #define PERMIT_NOT_SET -1 #define PERMIT_NO 0 #define PERMIT_FORCED_ONLY 1 #define PERMIT_NO_PASSWD 2 #define PERMIT_YES 3 /* use_privsep */ #define PRIVSEP_OFF 0 #define PRIVSEP_ON 1 #define PRIVSEP_NOSANDBOX 2 /* PermitOpen */ #define PERMITOPEN_ANY 0 #define PERMITOPEN_NONE -2 /* IgnoreRhosts */ #define IGNORE_RHOSTS_NO 0 #define IGNORE_RHOSTS_YES 1 #define IGNORE_RHOSTS_SHOSTS 2 #define DEFAULT_AUTH_FAIL_MAX 6 /* Default for MaxAuthTries */ #define DEFAULT_SESSIONS_MAX 10 /* Default for MaxSessions */ /* Magic name for internal sftp-server */ #define INTERNAL_SFTP_NAME "internal-sftp" /* PubkeyAuthOptions flags */ #define PUBKEYAUTH_TOUCH_REQUIRED (1) #define PUBKEYAUTH_VERIFY_REQUIRED (1<<1) struct ssh; struct fwd_perm_list; /* * Used to store addresses from ListenAddr directives. These may be * incomplete, as they may specify addresses that need to be merged * with any ports requested by ListenPort. */ struct queued_listenaddr { char *addr; int port; /* <=0 if unspecified */ char *rdomain; }; /* Resolved listen addresses, grouped by optional routing domain */ struct listenaddr { char *rdomain; struct addrinfo *addrs; }; typedef struct { u_int num_ports; u_int ports_from_cmdline; int ports[MAX_PORTS]; /* Port number to listen on. */ struct queued_listenaddr *queued_listen_addrs; u_int num_queued_listens; struct listenaddr *listen_addrs; u_int num_listen_addrs; int address_family; /* Address family used by the server. */ char *routing_domain; /* Bind session to routing domain */ char **host_key_files; /* Files containing host keys. */ int *host_key_file_userprovided; /* Key was specified by user. */ u_int num_host_key_files; /* Number of files for host keys. */ char **host_cert_files; /* Files containing host certs. */ u_int num_host_cert_files; /* Number of files for host certs. */ char *host_key_agent; /* ssh-agent socket for host keys. */ char *pid_file; /* Where to put our pid */ char *moduli_file; /* moduli file for DH-GEX */ int login_grace_time; /* Disconnect if no auth in this time * (sec). */ int permit_root_login; /* PERMIT_*, see above */ int ignore_rhosts; /* Ignore .rhosts and .shosts. */ int ignore_user_known_hosts; /* Ignore ~/.ssh/known_hosts * for RhostsRsaAuth */ int print_motd; /* If true, print /etc/motd. */ int print_lastlog; /* If true, print lastlog */ int x11_forwarding; /* If true, permit inet (spoofing) X11 fwd. */ int x11_display_offset; /* What DISPLAY number to start * searching at */ int x11_use_localhost; /* If true, use localhost for fake X11 server. */ char *xauth_location; /* Location of xauth program */ int permit_tty; /* If false, deny pty allocation */ int permit_user_rc; /* If false, deny ~/.ssh/rc execution */ int strict_modes; /* If true, require string home dir modes. */ int tcp_keep_alive; /* If true, set SO_KEEPALIVE. */ int ip_qos_interactive; /* IP ToS/DSCP/class for interactive */ int ip_qos_bulk; /* IP ToS/DSCP/class for bulk traffic */ char *ciphers; /* Supported SSH2 ciphers. */ char *macs; /* Supported SSH2 macs. */ char *kex_algorithms; /* SSH2 kex methods in order of preference. */ struct ForwardOptions fwd_opts; /* forwarding options */ SyslogFacility log_facility; /* Facility for system logging. */ LogLevel log_level; /* Level for system logging. */ u_int num_log_verbose; /* Verbose log overrides */ char **log_verbose; int hostbased_authentication; /* If true, permit ssh2 hostbased auth */ int hostbased_uses_name_from_packet_only; /* experimental */ char *hostbased_accepted_algos; /* Algos allowed for hostbased */ char *hostkeyalgorithms; /* SSH2 server key types */ char *ca_sign_algorithms; /* Allowed CA signature algorithms */ int pubkey_authentication; /* If true, permit ssh2 pubkey authentication. */ char *pubkey_accepted_algos; /* Signature algos allowed for pubkey */ int pubkey_auth_options; /* -1 or mask of PUBKEYAUTH_* flags */ int kerberos_authentication; /* If true, permit Kerberos * authentication. */ int kerberos_or_local_passwd; /* If true, permit kerberos * and any other password * authentication mechanism, * such as SecurID or * /etc/passwd */ int kerberos_ticket_cleanup; /* If true, destroy ticket * file on logout. */ int kerberos_get_afs_token; /* If true, try to get AFS token if * authenticated with Kerberos. */ int gss_authentication; /* If true, permit GSSAPI authentication */ int gss_keyex; /* If true, permit GSSAPI key exchange */ int gss_cleanup_creds; /* If true, destroy cred cache on logout */ int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */ int gss_store_rekey; char *gss_kex_algorithms; /* GSSAPI kex methods to be offered by client. */ int password_authentication; /* If true, permit password * authentication. */ int kbd_interactive_authentication; /* If true, permit */ int permit_empty_passwd; /* If false, do not permit empty * passwords. */ int permit_user_env; /* If true, read ~/.ssh/environment */ char *permit_user_env_allowlist; /* pattern-list of allowed env names */ int compression; /* If true, compression is allowed */ int allow_tcp_forwarding; /* One of FORWARD_* */ int allow_streamlocal_forwarding; /* One of FORWARD_* */ int allow_agent_forwarding; int disable_forwarding; u_int num_allow_users; char **allow_users; u_int num_deny_users; char **deny_users; u_int num_allow_groups; char **allow_groups; u_int num_deny_groups; char **deny_groups; u_int num_subsystems; char *subsystem_name[MAX_SUBSYSTEMS]; char *subsystem_command[MAX_SUBSYSTEMS]; char *subsystem_args[MAX_SUBSYSTEMS]; u_int num_accept_env; char **accept_env; u_int num_setenv; char **setenv; int max_startups_begin; int max_startups_rate; int max_startups; int per_source_max_startups; int per_source_masklen_ipv4; int per_source_masklen_ipv6; int max_authtries; int max_sessions; char *banner; /* SSH-2 banner message */ int use_dns; int client_alive_interval; /* * poke the client this often to * see if it's still there */ int client_alive_count_max; /* * If the client is unresponsive * for this many intervals above, * disconnect the session */ u_int num_authkeys_files; /* Files containing public keys */ char **authorized_keys_files; char *adm_forced_command; int use_pam; /* Enable auth via PAM */ int permit_tun; char **permitted_opens; /* May also be one of PERMITOPEN_* */ u_int num_permitted_opens; char **permitted_listens; /* May also be one of PERMITOPEN_* */ u_int num_permitted_listens; char *chroot_directory; char *revoked_keys_file; char *trusted_user_ca_keys; char *authorized_keys_command; char *authorized_keys_command_user; char *authorized_principals_file; char *authorized_principals_command; char *authorized_principals_command_user; int64_t rekey_limit; int rekey_interval; char *version_addendum; /* Appended to SSH banner */ u_int num_auth_methods; char **auth_methods; int fingerprint_hash; int expose_userauth_info; u_int64_t timing_secret; char *sk_provider; int debian_banner; } ServerOptions; /* Information about the incoming connection as used by Match */ struct connection_info { const char *user; const char *host; /* possibly resolved hostname */ const char *address; /* remote address */ const char *laddress; /* local address */ int lport; /* local port */ const char *rdomain; /* routing domain if available */ int test; /* test mode, allow some attributes to be * unspecified */ }; /* List of included files for re-exec from the parsed configuration */ struct include_item { char *selector; char *filename; struct sshbuf *contents; TAILQ_ENTRY(include_item) entry; }; TAILQ_HEAD(include_list, include_item); /* * These are string config options that must be copied between the * Match sub-config and the main config, and must be sent from the * privsep child to the privsep master. We use a macro to ensure all * the options are copied and the copies are done in the correct order. * * NB. an option must appear in servconf.c:copy_set_server_options() or * COPY_MATCH_STRING_OPTS here but never both. */ #define COPY_MATCH_STRING_OPTS() do { \ M_CP_STROPT(banner); \ M_CP_STROPT(trusted_user_ca_keys); \ M_CP_STROPT(revoked_keys_file); \ M_CP_STROPT(authorized_keys_command); \ M_CP_STROPT(authorized_keys_command_user); \ M_CP_STROPT(authorized_principals_file); \ M_CP_STROPT(authorized_principals_command); \ M_CP_STROPT(authorized_principals_command_user); \ M_CP_STROPT(hostbased_accepted_algos); \ M_CP_STROPT(pubkey_accepted_algos); \ M_CP_STROPT(ca_sign_algorithms); \ M_CP_STROPT(routing_domain); \ M_CP_STROPT(permit_user_env_allowlist); \ M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \ M_CP_STRARRAYOPT(allow_users, num_allow_users); \ M_CP_STRARRAYOPT(deny_users, num_deny_users); \ M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \ M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \ M_CP_STRARRAYOPT(accept_env, num_accept_env); \ M_CP_STRARRAYOPT(setenv, num_setenv); \ M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \ M_CP_STRARRAYOPT(permitted_opens, num_permitted_opens); \ M_CP_STRARRAYOPT(permitted_listens, num_permitted_listens); \ M_CP_STRARRAYOPT(log_verbose, num_log_verbose); \ } while (0) struct connection_info *get_connection_info(struct ssh *, int, int); void initialize_server_options(ServerOptions *); void fill_default_server_options(ServerOptions *); int process_server_config_line(ServerOptions *, char *, const char *, int, int *, struct connection_info *, struct include_list *includes); void process_permitopen(struct ssh *ssh, ServerOptions *options); void load_server_config(const char *, struct sshbuf *); void parse_server_config(ServerOptions *, const char *, struct sshbuf *, struct include_list *includes, struct connection_info *); void parse_server_match_config(ServerOptions *, struct include_list *includes, struct connection_info *); int parse_server_match_testspec(struct connection_info *, char *); int server_match_spec_complete(struct connection_info *); void copy_set_server_options(ServerOptions *, ServerOptions *, int); void dump_config(ServerOptions *); char *derelativise_path(const char *); void servconf_add_hostkey(const char *, const int, ServerOptions *, const char *path, int); void servconf_add_hostcert(const char *, const int, ServerOptions *, const char *path); #endif /* SERVCONF_H */