1 /* $NetBSD: readconf.h,v 1.36 2025/04/09 15:49:32 christos Exp $ */ 2 /* $OpenBSD: readconf.h,v 1.159 2025/02/15 01:48:30 djm Exp $ */ 3 4 /* 5 * Author: Tatu Ylonen <ylo@cs.hut.fi> 6 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 7 * All rights reserved 8 * Functions for reading the configuration file. 9 * 10 * As far as I am concerned, the code I have written for this software 11 * can be used freely for any purpose. Any derived versions of this 12 * software must be clearly marked as such, and if the derived work is 13 * incompatible with the protocol description in the RFC file, it must be 14 * called by a name other than "ssh" or "Secure Shell". 15 */ 16 17 #ifndef READCONF_H 18 #define READCONF_H 19 20 /* Data structure for representing option data. */ 21 22 #define SSH_MAX_HOSTS_FILES 32 23 #define PATH_MAX_SUN (sizeof((struct sockaddr_un *)0)->sun_path) 24 25 struct allowed_cname { 26 char *source_list; 27 char *target_list; 28 }; 29 30 typedef struct { 31 char *host_arg; /* Host arg as specified on command line. */ 32 int forward_agent; /* Forward authentication agent. */ 33 char *forward_agent_sock_path; /* Optional path of the agent. */ 34 int forward_x11; /* Forward X11 display. */ 35 int forward_x11_timeout; /* Expiration for Cookies */ 36 int forward_x11_trusted; /* Trust Forward X11 display. */ 37 int exit_on_forward_failure; /* Exit if bind(2) fails for -L/-R */ 38 char *xauth_location; /* Location for xauth program */ 39 struct ForwardOptions fwd_opts; /* forwarding options */ 40 int pubkey_authentication; /* Try ssh2 pubkey authentication. */ 41 int hostbased_authentication; /* ssh2's rhosts_rsa */ 42 #if defined(KRB4) || defined(KRB5) 43 int kerberos_authentication; /* Try Kerberos authentication. */ 44 #endif 45 #if defined(AFS) || defined(KRB5) 46 int kerberos_tgt_passing; /* Try Kerberos TGT passing. */ 47 #endif 48 #ifdef AFS 49 int afs_token_passing; /* Try AFS token passing. */ 50 #endif 51 /* Try S/Key or TIS, authentication. */ 52 int gss_authentication; /* Try GSS authentication */ 53 int gss_deleg_creds; /* Delegate GSS credentials */ 54 int password_authentication; /* Try password 55 * authentication. */ 56 int kbd_interactive_authentication; /* Try keyboard-interactive auth. */ 57 char *kbd_interactive_devices; /* Keyboard-interactive auth devices. */ 58 int batch_mode; /* Batch mode: do not ask for passwords. */ 59 int check_host_ip; /* Also keep track of keys for IP address */ 60 int strict_host_key_checking; /* Strict host key checking. */ 61 int compression; /* Compress packets in both directions. */ 62 int tcp_keep_alive; /* Set SO_KEEPALIVE. */ 63 int ip_qos_interactive; /* IP ToS/DSCP/class for interactive */ 64 int ip_qos_bulk; /* IP ToS/DSCP/class for bulk traffic */ 65 int tcp_rcv_buf; /* user switch to set tcp recv buffer */ 66 int tcp_rcv_buf_poll; /* Option to poll recv buf every window transfer */ 67 int hpn_disabled; /* Switch to disable HPN buffer management */ 68 int hpn_buffer_size; /* User definable size for HPN buffer window */ 69 70 SyslogFacility log_facility; /* Facility for system logging. */ 71 LogLevel log_level; /* Level for logging. */ 72 u_int num_log_verbose; /* Verbose log overrides */ 73 char **log_verbose; 74 int port; /* Port to connect. */ 75 int address_family; 76 int connection_attempts; /* Max attempts (seconds) before 77 * giving up */ 78 int connection_timeout; /* Max time (seconds) before 79 * aborting connection attempt */ 80 int number_of_password_prompts; /* Max number of password 81 * prompts. */ 82 char *ciphers; /* SSH2 ciphers in order of preference. */ 83 char *macs; /* SSH2 macs in order of preference. */ 84 char *hostkeyalgorithms; /* SSH2 server key types in order of preference. */ 85 char *kex_algorithms; /* SSH2 kex methods in order of preference. */ 86 char *ca_sign_algorithms; /* Allowed CA signature algorithms */ 87 char *hostname; /* Real host to connect. */ 88 char *tag; /* Configuration tag name. */ 89 char *host_key_alias; /* hostname alias for .ssh/known_hosts */ 90 char *proxy_command; /* Proxy command for connecting the host. */ 91 char *user; /* User to log in as. */ 92 int escape_char; /* Escape character; -2 = none */ 93 94 u_int num_system_hostfiles; /* Paths for /etc/ssh/ssh_known_hosts */ 95 char *system_hostfiles[SSH_MAX_HOSTS_FILES]; 96 u_int num_user_hostfiles; /* Path for $HOME/.ssh/known_hosts */ 97 char *user_hostfiles[SSH_MAX_HOSTS_FILES]; 98 char *preferred_authentications; 99 char *bind_address; /* local socket address for connection to sshd */ 100 char *bind_interface; /* local interface for bind address */ 101 int ipv6_prefer_temporary; /* Prefer temporary IPv6 address */ 102 char *pkcs11_provider; /* PKCS#11 provider */ 103 char *sk_provider; /* Security key provider */ 104 int verify_host_key_dns; /* Verify host key using DNS */ 105 106 int num_identity_files; /* Number of files for identities. */ 107 char *identity_files[SSH_MAX_IDENTITY_FILES]; 108 int identity_file_userprovided[SSH_MAX_IDENTITY_FILES]; 109 struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES]; 110 111 int num_certificate_files; /* Number of extra certificates for ssh. */ 112 char *certificate_files[SSH_MAX_CERTIFICATE_FILES]; 113 int certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES]; 114 struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES]; 115 116 int add_keys_to_agent; 117 int add_keys_to_agent_lifespan; 118 char *identity_agent; /* Optional path to ssh-agent socket */ 119 120 /* Local TCP/IP forward requests. */ 121 int num_local_forwards; 122 struct Forward *local_forwards; 123 124 /* Remote TCP/IP forward requests. */ 125 int num_remote_forwards; 126 struct Forward *remote_forwards; 127 int clear_forwardings; 128 129 /* Restrict remote dynamic forwarding */ 130 char **permitted_remote_opens; 131 u_int num_permitted_remote_opens; 132 133 /* stdio forwarding (-W) host and port */ 134 char *stdio_forward_host; 135 int stdio_forward_port; 136 137 int enable_ssh_keysign; 138 int64_t rekey_limit; 139 int rekey_interval; 140 int none_switch; /* Use none cipher */ 141 int none_enabled; /* Allow none to be used */ 142 int no_host_authentication_for_localhost; 143 int identities_only; 144 int server_alive_interval; 145 int server_alive_count_max; 146 147 u_int num_send_env; 148 char **send_env; 149 u_int num_setenv; 150 char **setenv; 151 152 char *control_path; 153 int control_master; 154 int control_persist; /* ControlPersist flag */ 155 int control_persist_timeout; /* ControlPersist timeout (seconds) */ 156 157 int hash_known_hosts; 158 159 int tun_open; /* tun(4) */ 160 int tun_local; /* force tun device (optional) */ 161 int tun_remote; /* force tun device (optional) */ 162 163 char *local_command; 164 int permit_local_command; 165 char *remote_command; 166 int visual_host_key; 167 168 int request_tty; 169 int send_version_first; 170 int session_type; 171 int stdin_null; 172 int fork_after_authentication; 173 174 int proxy_use_fdpass; 175 176 int num_canonical_domains; 177 char **canonical_domains; 178 int canonicalize_hostname; 179 int canonicalize_max_dots; 180 int canonicalize_fallback_local; 181 int num_permitted_cnames; 182 struct allowed_cname *permitted_cnames; 183 184 char *revoked_host_keys; 185 186 int fingerprint_hash; 187 188 int update_hostkeys; /* one of SSH_UPDATE_HOSTKEYS_* */ 189 190 char *hostbased_accepted_algos; 191 char *pubkey_accepted_algos; 192 193 char *jump_user; 194 char *jump_host; 195 int jump_port; 196 char *jump_extra; 197 198 char *known_hosts_command; 199 200 int required_rsa_size; /* minimum size of RSA keys */ 201 int enable_escape_commandline; /* ~C commandline */ 202 int obscure_keystroke_timing_interval; 203 204 char **channel_timeouts; /* inactivity timeout by channel type */ 205 u_int num_channel_timeouts; 206 207 char *version_addendum; 208 209 char *ignored_unknown; /* Pattern list of unknown tokens to ignore */ 210 } Options; 211 212 #define SSH_PUBKEY_AUTH_NO 0x00 213 #define SSH_PUBKEY_AUTH_UNBOUND 0x01 214 #define SSH_PUBKEY_AUTH_HBOUND 0x02 215 #define SSH_PUBKEY_AUTH_ALL 0x03 216 217 #define SSH_CANONICALISE_NO 0 218 #define SSH_CANONICALISE_YES 1 219 #define SSH_CANONICALISE_ALWAYS 2 220 221 #define SSHCTL_MASTER_NO 0 222 #define SSHCTL_MASTER_YES 1 223 #define SSHCTL_MASTER_AUTO 2 224 #define SSHCTL_MASTER_ASK 3 225 #define SSHCTL_MASTER_AUTO_ASK 4 226 227 #define REQUEST_TTY_AUTO 0 228 #define REQUEST_TTY_NO 1 229 #define REQUEST_TTY_YES 2 230 #define REQUEST_TTY_FORCE 3 231 232 #define SESSION_TYPE_NONE 0 233 #define SESSION_TYPE_SUBSYSTEM 1 234 #define SESSION_TYPE_DEFAULT 2 235 236 #define SSHCONF_CHECKPERM 1 /* check permissions on config file */ 237 #define SSHCONF_USERCONF 2 /* user provided config file not system */ 238 #define SSHCONF_FINAL 4 /* Final pass over config, after canon. */ 239 #define SSHCONF_NEVERMATCH 8 /* Match/Host never matches; internal only */ 240 241 #define SSH_UPDATE_HOSTKEYS_NO 0 242 #define SSH_UPDATE_HOSTKEYS_YES 1 243 #define SSH_UPDATE_HOSTKEYS_ASK 2 244 245 #define SSH_STRICT_HOSTKEY_OFF 0 246 #define SSH_STRICT_HOSTKEY_NEW 1 247 #define SSH_STRICT_HOSTKEY_YES 2 248 #define SSH_STRICT_HOSTKEY_ASK 3 249 250 /* ObscureKeystrokes parameters */ 251 #define SSH_KEYSTROKE_DEFAULT_INTERVAL_MS 20 252 #define SSH_KEYSTROKE_CHAFF_MIN_MS 1024 253 #define SSH_KEYSTROKE_CHAFF_RNG_MS 2048 254 255 const char *kex_default_pk_alg(void); 256 char *ssh_connection_hash(const char *thishost, const char *host, 257 const char *portstr, const char *user, const char *jump_host); 258 void initialize_options(Options *); 259 int fill_default_options(Options *); 260 void fill_default_options_for_canonicalization(Options *); 261 void free_options(Options *o); 262 int process_config_line(Options *, struct passwd *, const char *, 263 const char *, const char *, char *, const char *, int, int *, int); 264 int read_config_file(const char *, struct passwd *, const char *, 265 const char *, const char *, Options *, int, int *); 266 int parse_forward(struct Forward *, const char *, int, int); 267 int parse_jump(const char *, Options *, int); 268 int parse_ssh_uri(const char *, char **, char **, int *); 269 int default_ssh_port(void); 270 int option_clear_or_none(const char *); 271 int config_has_permitted_cnames(Options *); 272 void dump_client_config(Options *o, const char *host); 273 274 void add_local_forward(Options *, const struct Forward *); 275 void add_remote_forward(Options *, const struct Forward *); 276 void add_identity_file(Options *, const char *, const char *, int); 277 void add_certificate_file(Options *, const char *, int); 278 279 #endif /* READCONF_H */ 280