crypto/openssh/servconf.h

   1 /* $OpenBSD: servconf.h,v 1.114 2014/07/15 15:54:14 millert 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 #define DEFAULT_AUTH_FAIL_MAX   6       /* Default for MaxAuthTries */
  52 #define DEFAULT_SESSIONS_MAX    10      /* Default for MaxSessions */
  53
  54 /* Magic name for internal sftp-server */
  55 #define INTERNAL_SFTP_NAME      "internal-sftp"
  56
  57 typedef struct {
  58         u_int   num_ports;
  59         u_int   ports_from_cmdline;
  60         int     ports[MAX_PORTS];       /* Port number to listen on. */
  61         char   *listen_addr;            /* Address on which the server listens. */
  62         struct addrinfo *listen_addrs;  /* Addresses on which the server listens. */
  63         int     address_family;         /* Address family used by the server. */
  64         char   *host_key_files[MAX_HOSTKEYS];   /* Files containing host keys. */
  65         int     num_host_key_files;     /* Number of files for host keys. */
  66         char   *host_cert_files[MAX_HOSTCERTS]; /* Files containing host certs. */
  67         int     num_host_cert_files;     /* Number of files for host certs. */
  68         char   *host_key_agent;          /* ssh-agent socket for host keys. */
  69         char   *pid_file;       /* Where to put our pid */
  70         int     server_key_bits;/* Size of the server key. */
  71         int     login_grace_time;       /* Disconnect if no auth in this time
  72                                          * (sec). */
  73         int     key_regeneration_time;  /* Server key lifetime (seconds). */
  74         int     permit_root_login;      /* PERMIT_*, see above */
  75         int     ignore_rhosts;  /* Ignore .rhosts and .shosts. */
  76         int     ignore_user_known_hosts;        /* Ignore ~/.ssh/known_hosts
  77                                                  * for RhostsRsaAuth */
  78         int     print_motd;     /* If true, print /etc/motd. */
  79         int     print_lastlog;  /* If true, print lastlog */
  80         int     x11_forwarding; /* If true, permit inet (spoofing) X11 fwd. */
  81         int     x11_display_offset;     /* What DISPLAY number to start
  82                                          * searching at */
  83         int     x11_use_localhost;      /* If true, use localhost for fake X11 server. */
  84         char   *xauth_location; /* Location of xauth program */
  85         int     permit_tty;     /* If false, deny pty allocation */
  86         int     permit_user_rc; /* If false, deny ~/.ssh/rc execution */
  87         int     strict_modes;   /* If true, require string home dir modes. */
  88         int     tcp_keep_alive; /* If true, set SO_KEEPALIVE. */
  89         int     ip_qos_interactive;     /* IP ToS/DSCP/class for interactive */
  90         int     ip_qos_bulk;            /* IP ToS/DSCP/class for bulk traffic */
  91         char   *ciphers;        /* Supported SSH2 ciphers. */
  92         char   *macs;           /* Supported SSH2 macs. */
  93         char   *kex_algorithms; /* SSH2 kex methods in order of preference. */
  94         int     protocol;       /* Supported protocol versions. */
  95         struct ForwardOptions fwd_opts; /* forwarding options */
  96         SyslogFacility log_facility;    /* Facility for system logging. */
  97         LogLevel log_level;     /* Level for system logging. */
  98         int     rhosts_rsa_authentication;      /* If true, permit rhosts RSA
  99                                                  * authentication. */
 100         int     hostbased_authentication;       /* If true, permit ssh2 hostbased auth */
 101         int     hostbased_uses_name_from_packet_only; /* experimental */
 102         int     rsa_authentication;     /* If true, permit RSA authentication. */
 103         int     pubkey_authentication;  /* If true, permit ssh2 pubkey authentication. */
 104         int     kerberos_authentication;        /* If true, permit Kerberos
 105                                                  * authentication. */
 106         int     kerberos_or_local_passwd;       /* If true, permit kerberos
 107                                                  * and any other password
 108                                                  * authentication mechanism,
 109                                                  * such as SecurID or
 110                                                  * /etc/passwd */
 111         int     kerberos_ticket_cleanup;        /* If true, destroy ticket
 112                                                  * file on logout. */
 113         int     kerberos_get_afs_token;         /* If true, try to get AFS token if
 114                                                  * authenticated with Kerberos. */
 115         int     gss_authentication;     /* If true, permit GSSAPI authentication */
 116         int     gss_cleanup_creds;      /* If true, destroy cred cache on logout */
 117         int     password_authentication;        /* If true, permit password
 118                                                  * authentication. */
 119         int     kbd_interactive_authentication; /* If true, permit */
 120         int     challenge_response_authentication;
 121         int     permit_empty_passwd;    /* If false, do not permit empty
 122                                          * passwords. */
 123         int     permit_user_env;        /* If true, read ~/.ssh/environment */
 124         int     use_login;      /* If true, login(1) is used */
 125         int     compression;    /* If true, compression is allowed */
 126         int     allow_tcp_forwarding; /* One of FORWARD_* */
 127         int     allow_streamlocal_forwarding; /* One of FORWARD_* */
 128         int     allow_agent_forwarding;
 129         u_int num_allow_users;
 130         char   *allow_users[MAX_ALLOW_USERS];
 131         u_int num_deny_users;
 132         char   *deny_users[MAX_DENY_USERS];
 133         u_int num_allow_groups;
 134         char   *allow_groups[MAX_ALLOW_GROUPS];
 135         u_int num_deny_groups;
 136         char   *deny_groups[MAX_DENY_GROUPS];
 137
 138         u_int num_subsystems;
 139         char   *subsystem_name[MAX_SUBSYSTEMS];
 140         char   *subsystem_command[MAX_SUBSYSTEMS];
 141         char   *subsystem_args[MAX_SUBSYSTEMS];
 142
 143         u_int num_accept_env;
 144         char   *accept_env[MAX_ACCEPT_ENV];
 145
 146         int     max_startups_begin;
 147         int     max_startups_rate;
 148         int     max_startups;
 149         int     max_authtries;
 150         int     max_sessions;
 151         char   *banner;                 /* SSH-2 banner message */
 152         int     use_dns;
 153         int     client_alive_interval;  /*
 154                                          * poke the client this often to
 155                                          * see if it's still there
 156                                          */
 157         int     client_alive_count_max; /*
 158                                          * If the client is unresponsive
 159                                          * for this many intervals above,
 160                                          * disconnect the session
 161                                          */
 162
 163         u_int num_authkeys_files;       /* Files containing public keys */
 164         char   *authorized_keys_files[MAX_AUTHKEYS_FILES];
 165
 166         char   *adm_forced_command;
 167
 168         int     use_pam;                /* Enable auth via PAM */
 169
 170         int     permit_tun;
 171
 172         int     num_permitted_opens;
 173
 174         char   *chroot_directory;
 175         char   *revoked_keys_file;
 176         char   *trusted_user_ca_keys;
 177         char   *authorized_principals_file;
 178         char   *authorized_keys_command;
 179         char   *authorized_keys_command_user;
 180
 181         int64_t rekey_limit;
 182         int     rekey_interval;
 183
 184         char   *version_addendum;       /* Appended to SSH banner */
 185
 186         u_int   num_auth_methods;
 187         char   *auth_methods[MAX_AUTH_METHODS];
 188 }       ServerOptions;
 189
 190 /* Information about the incoming connection as used by Match */
 191 struct connection_info {
 192         const char *user;
 193         const char *host;       /* possibly resolved hostname */
 194         const char *address;    /* remote address */
 195         const char *laddress;   /* local address */
 196         int lport;              /* local port */
 197 };
 198
 199
 200 /*
 201  * These are string config options that must be copied between the
 202  * Match sub-config and the main config, and must be sent from the
 203  * privsep slave to the privsep master. We use a macro to ensure all
 204  * the options are copied and the copies are done in the correct order.
 205  *
 206  * NB. an option must appear in servconf.c:copy_set_server_options() or
 207  * COPY_MATCH_STRING_OPTS here but never both.
 208  */
 209 #define COPY_MATCH_STRING_OPTS() do { \
 210                 M_CP_STROPT(banner); \
 211                 M_CP_STROPT(trusted_user_ca_keys); \
 212                 M_CP_STROPT(revoked_keys_file); \
 213                 M_CP_STROPT(authorized_principals_file); \
 214                 M_CP_STROPT(authorized_keys_command); \
 215                 M_CP_STROPT(authorized_keys_command_user); \
 216                 M_CP_STRARRAYOPT(authorized_keys_files, num_authkeys_files); \
 217                 M_CP_STRARRAYOPT(allow_users, num_allow_users); \
 218                 M_CP_STRARRAYOPT(deny_users, num_deny_users); \
 219                 M_CP_STRARRAYOPT(allow_groups, num_allow_groups); \
 220                 M_CP_STRARRAYOPT(deny_groups, num_deny_groups); \
 221                 M_CP_STRARRAYOPT(accept_env, num_accept_env); \
 222                 M_CP_STRARRAYOPT(auth_methods, num_auth_methods); \
 223         } while (0)
 224
 225 struct connection_info *get_connection_info(int, int);
 226 void     initialize_server_options(ServerOptions *);
 227 void     fill_default_server_options(ServerOptions *);
 228 int      process_server_config_line(ServerOptions *, char *, const char *, int,
 229              int *, struct connection_info *);
 230 void     load_server_config(const char *, Buffer *);
 231 void     parse_server_config(ServerOptions *, const char *, Buffer *,
 232              struct connection_info *);
 233 void     parse_server_match_config(ServerOptions *, struct connection_info *);
 234 int      parse_server_match_testspec(struct connection_info *, char *);
 235 int      server_match_spec_complete(struct connection_info *);
 236 void     copy_set_server_options(ServerOptions *, ServerOptions *, int);
 237 void     dump_config(ServerOptions *);
 238 char    *derelativise_path(const char *);
 239
 240 #endif                          /* SERVCONF_H */