1 /* $OpenBSD: readconf.h,v 1.161 2025/08/11 10:55:38 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 * Functions for reading the configuration file. 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 READCONF_H 17 #define READCONF_H 18 19 /* Data structure for representing option data. */ 20 21 #define SSH_MAX_HOSTS_FILES 32 22 #define PATH_MAX_SUN (sizeof((struct sockaddr_un *)0)->sun_path) 23 24 struct allowed_cname { 25 char *source_list; 26 char *target_list; 27 }; 28 29 typedef struct { 30 char *host_arg; /* Host arg as specified on command line. */ 31 int forward_agent; /* Forward authentication agent. */ 32 char *forward_agent_sock_path; /* Optional path of the agent. */ 33 int forward_x11; /* Forward X11 display. */ 34 int forward_x11_timeout; /* Expiration for Cookies */ 35 int forward_x11_trusted; /* Trust Forward X11 display. */ 36 int exit_on_forward_failure; /* Exit if bind(2) fails for -L/-R */ 37 char *xauth_location; /* Location for xauth program */ 38 struct ForwardOptions fwd_opts; /* forwarding options */ 39 int pubkey_authentication; /* Try ssh2 pubkey authentication. */ 40 int hostbased_authentication; /* ssh2's rhosts_rsa */ 41 int gss_authentication; /* Try GSS authentication */ 42 int gss_deleg_creds; /* Delegate GSS credentials */ 43 int password_authentication; /* Try password 44 * authentication. */ 45 int kbd_interactive_authentication; /* Try keyboard-interactive auth. */ 46 char *kbd_interactive_devices; /* Keyboard-interactive auth devices. */ 47 int batch_mode; /* Batch mode: do not ask for passwords. */ 48 int check_host_ip; /* Also keep track of keys for IP address */ 49 int strict_host_key_checking; /* Strict host key checking. */ 50 int compression; /* Compress packets in both directions. */ 51 int tcp_keep_alive; /* Set SO_KEEPALIVE. */ 52 int ip_qos_interactive; /* DSCP value for interactive */ 53 int ip_qos_bulk; /* DSCP value for bulk traffic */ 54 SyslogFacility log_facility; /* Facility for system logging. */ 55 LogLevel log_level; /* Level for logging. */ 56 u_int num_log_verbose; /* Verbose log overrides */ 57 char **log_verbose; 58 int port; /* Port to connect. */ 59 int address_family; 60 int connection_attempts; /* Max attempts (seconds) before 61 * giving up */ 62 int connection_timeout; /* Max time (seconds) before 63 * aborting connection attempt */ 64 int number_of_password_prompts; /* Max number of password 65 * prompts. */ 66 char *ciphers; /* SSH2 ciphers in order of preference. */ 67 char *macs; /* SSH2 macs in order of preference. */ 68 char *hostkeyalgorithms; /* SSH2 server key types in order of preference. */ 69 char *kex_algorithms; /* SSH2 kex methods in order of preference. */ 70 int kex_algorithms_set; /* KexAlgorithms was set by the user */ 71 char *ca_sign_algorithms; /* Allowed CA signature algorithms */ 72 char *hostname; /* Real host to connect. */ 73 char *tag; /* Configuration tag name. */ 74 char *host_key_alias; /* hostname alias for .ssh/known_hosts */ 75 char *proxy_command; /* Proxy command for connecting the host. */ 76 char *user; /* User to log in as. */ 77 int escape_char; /* Escape character; -2 = none */ 78 79 u_int num_system_hostfiles; /* Paths for /etc/ssh/ssh_known_hosts */ 80 char *system_hostfiles[SSH_MAX_HOSTS_FILES]; 81 u_int num_user_hostfiles; /* Path for $HOME/.ssh/known_hosts */ 82 char *user_hostfiles[SSH_MAX_HOSTS_FILES]; 83 char *preferred_authentications; 84 char *bind_address; /* local socket address for connection to sshd */ 85 char *bind_interface; /* local interface for bind address */ 86 char *pkcs11_provider; /* PKCS#11 provider */ 87 char *sk_provider; /* Security key provider */ 88 int verify_host_key_dns; /* Verify host key using DNS */ 89 90 int num_identity_files; /* Number of files for identities. */ 91 char *identity_files[SSH_MAX_IDENTITY_FILES]; 92 int identity_file_userprovided[SSH_MAX_IDENTITY_FILES]; 93 struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES]; 94 95 int num_certificate_files; /* Number of extra certificates for ssh. */ 96 char *certificate_files[SSH_MAX_CERTIFICATE_FILES]; 97 int certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES]; 98 struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES]; 99 100 int add_keys_to_agent; 101 int add_keys_to_agent_lifespan; 102 char *identity_agent; /* Optional path to ssh-agent socket */ 103 104 /* Local TCP/IP forward requests. */ 105 int num_local_forwards; 106 struct Forward *local_forwards; 107 108 /* Remote TCP/IP forward requests. */ 109 int num_remote_forwards; 110 struct Forward *remote_forwards; 111 int clear_forwardings; 112 113 /* Restrict remote dynamic forwarding */ 114 char **permitted_remote_opens; 115 u_int num_permitted_remote_opens; 116 117 /* stdio forwarding (-W) host and port */ 118 char *stdio_forward_host; 119 int stdio_forward_port; 120 121 int enable_ssh_keysign; 122 int64_t rekey_limit; 123 int rekey_interval; 124 int no_host_authentication_for_localhost; 125 int identities_only; 126 int server_alive_interval; 127 int server_alive_count_max; 128 129 u_int num_send_env; 130 char **send_env; 131 u_int num_setenv; 132 char **setenv; 133 134 char *control_path; 135 int control_master; 136 int control_persist; /* ControlPersist flag */ 137 int control_persist_timeout; /* ControlPersist timeout (seconds) */ 138 139 int hash_known_hosts; 140 141 int tun_open; /* tun(4) */ 142 int tun_local; /* force tun device (optional) */ 143 int tun_remote; /* force tun device (optional) */ 144 145 char *local_command; 146 int permit_local_command; 147 char *remote_command; 148 int visual_host_key; 149 150 int request_tty; 151 int session_type; 152 int stdin_null; 153 int fork_after_authentication; 154 155 int proxy_use_fdpass; 156 157 int num_canonical_domains; 158 char **canonical_domains; 159 int canonicalize_hostname; 160 int canonicalize_max_dots; 161 int canonicalize_fallback_local; 162 int num_permitted_cnames; 163 struct allowed_cname *permitted_cnames; 164 165 char *revoked_host_keys; 166 167 int fingerprint_hash; 168 169 int update_hostkeys; /* one of SSH_UPDATE_HOSTKEYS_* */ 170 171 char *hostbased_accepted_algos; 172 char *pubkey_accepted_algos; 173 174 char *jump_user; 175 char *jump_host; 176 int jump_port; 177 char *jump_extra; 178 179 char *known_hosts_command; 180 181 int required_rsa_size; /* minimum size of RSA keys */ 182 int enable_escape_commandline; /* ~C commandline */ 183 int obscure_keystroke_timing_interval; 184 int warn_weak_crypto; 185 186 char **channel_timeouts; /* inactivity timeout by channel type */ 187 u_int num_channel_timeouts; 188 189 char *version_addendum; 190 191 char *ignored_unknown; /* Pattern list of unknown tokens to ignore */ 192 } Options; 193 194 #define SSH_PUBKEY_AUTH_NO 0x00 195 #define SSH_PUBKEY_AUTH_UNBOUND 0x01 196 #define SSH_PUBKEY_AUTH_HBOUND 0x02 197 #define SSH_PUBKEY_AUTH_ALL 0x03 198 199 #define SSH_CANONICALISE_NO 0 200 #define SSH_CANONICALISE_YES 1 201 #define SSH_CANONICALISE_ALWAYS 2 202 203 #define SSHCTL_MASTER_NO 0 204 #define SSHCTL_MASTER_YES 1 205 #define SSHCTL_MASTER_AUTO 2 206 #define SSHCTL_MASTER_ASK 3 207 #define SSHCTL_MASTER_AUTO_ASK 4 208 209 #define REQUEST_TTY_AUTO 0 210 #define REQUEST_TTY_NO 1 211 #define REQUEST_TTY_YES 2 212 #define REQUEST_TTY_FORCE 3 213 214 #define SESSION_TYPE_NONE 0 215 #define SESSION_TYPE_SUBSYSTEM 1 216 #define SESSION_TYPE_DEFAULT 2 217 218 #define SSHCONF_CHECKPERM 1 /* check permissions on config file */ 219 #define SSHCONF_USERCONF 2 /* user provided config file not system */ 220 #define SSHCONF_FINAL 4 /* Final pass over config, after canon. */ 221 #define SSHCONF_NEVERMATCH 8 /* Match/Host never matches; internal only */ 222 223 #define SSH_UPDATE_HOSTKEYS_NO 0 224 #define SSH_UPDATE_HOSTKEYS_YES 1 225 #define SSH_UPDATE_HOSTKEYS_ASK 2 226 227 #define SSH_STRICT_HOSTKEY_OFF 0 228 #define SSH_STRICT_HOSTKEY_NEW 1 229 #define SSH_STRICT_HOSTKEY_YES 2 230 #define SSH_STRICT_HOSTKEY_ASK 3 231 232 /* ObscureKeystrokes parameters */ 233 #define SSH_KEYSTROKE_DEFAULT_INTERVAL_MS 20 234 #define SSH_KEYSTROKE_CHAFF_MIN_MS 1024 235 #define SSH_KEYSTROKE_CHAFF_RNG_MS 2048 236 237 const char *kex_default_pk_alg(void); 238 char *ssh_connection_hash(const char *thishost, const char *host, 239 const char *portstr, const char *user, const char *jump_host); 240 void initialize_options(Options *); 241 int fill_default_options(Options *); 242 void fill_default_options_for_canonicalization(Options *); 243 void free_options(Options *o); 244 int process_config_line(Options *, struct passwd *, const char *, 245 const char *, const char *, char *, const char *, int, int *, int); 246 int read_config_file(const char *, struct passwd *, const char *, 247 const char *, const char *, Options *, int, int *); 248 int parse_forward(struct Forward *, const char *, int, int); 249 int parse_jump(const char *, Options *, int); 250 int parse_ssh_uri(const char *, char **, char **, int *); 251 int default_ssh_port(void); 252 int option_clear_or_none(const char *); 253 int config_has_permitted_cnames(Options *); 254 void dump_client_config(Options *o, const char *host); 255 256 void add_local_forward(Options *, const struct Forward *); 257 void add_remote_forward(Options *, const struct Forward *); 258 void add_identity_file(Options *, const char *, const char *, int); 259 void add_certificate_file(Options *, const char *, int); 260 261 #endif /* READCONF_H */ 262