Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 1 | /* |
| 2 | |
| 3 | ssh.h |
| 4 | |
| 5 | Author: Tatu Ylonen <ylo@cs.hut.fi> |
| 6 | |
| 7 | Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 8 | All rights reserved |
| 9 | |
| 10 | Created: Fri Mar 17 17:09:37 1995 ylo |
| 11 | |
| 12 | Generic header file for ssh. |
| 13 | |
| 14 | */ |
| 15 | |
Damien Miller | 5ce662a | 1999-11-11 17:57:39 +1100 | [diff] [blame^] | 16 | /* RCSID("$Id: ssh.h,v 1.10 1999/11/11 06:57:40 damien Exp $"); */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 17 | |
| 18 | #ifndef SSH_H |
| 19 | #define SSH_H |
| 20 | |
Damien Miller | ab18c41 | 1999-11-11 10:40:23 +1100 | [diff] [blame] | 21 | #include <netinet/in.h> /* For struct sockaddr_in */ |
| 22 | #include <pwd.h> /* For struct pw */ |
Damien Miller | 5ce662a | 1999-11-11 17:57:39 +1100 | [diff] [blame^] | 23 | #include <stdarg.h> /* For va_list */ |
Damien Miller | 7f6ea02 | 1999-10-28 13:25:17 +1000 | [diff] [blame] | 24 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 25 | #include "rsa.h" |
| 26 | #include "cipher.h" |
| 27 | |
| 28 | /* The default cipher used if IDEA is not supported by the remote host. |
| 29 | It is recommended that this be one of the mandatory ciphers (DES, 3DES), |
| 30 | though that is not required. */ |
| 31 | #define SSH_FALLBACK_CIPHER SSH_CIPHER_3DES |
| 32 | |
| 33 | /* Cipher used for encrypting authentication files. */ |
| 34 | #define SSH_AUTHFILE_CIPHER SSH_CIPHER_3DES |
| 35 | |
| 36 | /* Default port number. */ |
| 37 | #define SSH_DEFAULT_PORT 22 |
| 38 | |
| 39 | /* Maximum number of TCP/IP ports forwarded per direction. */ |
| 40 | #define SSH_MAX_FORWARDS_PER_DIRECTION 100 |
| 41 | |
| 42 | /* Maximum number of RSA authentication identity files that can be specified |
| 43 | in configuration files or on the command line. */ |
| 44 | #define SSH_MAX_IDENTITY_FILES 100 |
| 45 | |
| 46 | /* Major protocol version. Different version indicates major incompatiblity |
| 47 | that prevents communication. */ |
| 48 | #define PROTOCOL_MAJOR 1 |
| 49 | |
| 50 | /* Minor protocol version. Different version indicates minor incompatibility |
| 51 | that does not prevent interoperation. */ |
| 52 | #define PROTOCOL_MINOR 5 |
| 53 | |
| 54 | /* Name for the service. The port named by this service overrides the default |
| 55 | port if present. */ |
| 56 | #define SSH_SERVICE_NAME "ssh" |
| 57 | |
| 58 | #ifndef ETCDIR |
| 59 | #define ETCDIR "/etc" |
| 60 | #endif /* ETCDIR */ |
| 61 | |
| 62 | #define PIDDIR "/var/run" |
| 63 | |
| 64 | /* System-wide file containing host keys of known hosts. This file should be |
| 65 | world-readable. */ |
| 66 | #define SSH_SYSTEM_HOSTFILE ETCDIR "/ssh_known_hosts" |
| 67 | |
| 68 | /* HOST_KEY_FILE /etc/ssh_host_key, |
| 69 | SERVER_CONFIG_FILE /etc/sshd_config, |
| 70 | and HOST_CONFIG_FILE /etc/ssh_config |
| 71 | are all defined in Makefile.in. Of these, ssh_host_key should be readable |
| 72 | only by root, whereas ssh_config should be world-readable. */ |
| 73 | |
| 74 | #define HOST_KEY_FILE ETCDIR "/ssh_host_key" |
| 75 | #define SERVER_CONFIG_FILE ETCDIR "/sshd_config" |
| 76 | #define HOST_CONFIG_FILE ETCDIR "/ssh_config" |
| 77 | |
Damien Miller | 356a0b0 | 1999-11-08 15:30:59 +1100 | [diff] [blame] | 78 | #ifndef SSH_PROGRAM |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 79 | #define SSH_PROGRAM "/usr/bin/ssh" |
Damien Miller | 356a0b0 | 1999-11-08 15:30:59 +1100 | [diff] [blame] | 80 | #endif /* SSH_PROGRAM */ |
| 81 | |
| 82 | #ifndef LOGIN_PROGRAM |
| 83 | #define LOGIN_PROGRAM "/usr/bin/login" |
| 84 | #endif /* LOGIN_PROGRAM */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 85 | |
Damien Miller | c7b38ce | 1999-11-09 10:28:04 +1100 | [diff] [blame] | 86 | #ifndef ASKPASS_PROGRAM |
| 87 | #define ASKPASS_PROGRAM "/usr/lib/ssh/ssh-askpass" |
| 88 | #endif /* ASKPASS_PROGRAM */ |
| 89 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 90 | /* The process id of the daemon listening for connections is saved |
| 91 | here to make it easier to kill the correct daemon when necessary. */ |
Damien Miller | a37010e | 1999-10-29 09:18:29 +1000 | [diff] [blame] | 92 | #define SSH_DAEMON_PID_FILE PIDDIR "/sshd.pid" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 93 | |
| 94 | /* The directory in user\'s home directory in which the files reside. |
| 95 | The directory should be world-readable (though not all files are). */ |
| 96 | #define SSH_USER_DIR ".ssh" |
| 97 | |
| 98 | /* Per-user file containing host keys of known hosts. This file need |
| 99 | not be readable by anyone except the user him/herself, though this does |
| 100 | not contain anything particularly secret. */ |
| 101 | #define SSH_USER_HOSTFILE "~/.ssh/known_hosts" |
| 102 | |
| 103 | /* Name of the default file containing client-side authentication key. |
| 104 | This file should only be readable by the user him/herself. */ |
| 105 | #define SSH_CLIENT_IDENTITY ".ssh/identity" |
| 106 | |
| 107 | /* Configuration file in user\'s home directory. This file need not be |
| 108 | readable by anyone but the user him/herself, but does not contain |
| 109 | anything particularly secret. If the user\'s home directory resides |
| 110 | on an NFS volume where root is mapped to nobody, this may need to be |
| 111 | world-readable. */ |
| 112 | #define SSH_USER_CONFFILE ".ssh/config" |
| 113 | |
| 114 | /* File containing a list of those rsa keys that permit logging in as |
| 115 | this user. This file need not be |
| 116 | readable by anyone but the user him/herself, but does not contain |
| 117 | anything particularly secret. If the user\'s home directory resides |
| 118 | on an NFS volume where root is mapped to nobody, this may need to be |
| 119 | world-readable. (This file is read by the daemon which is running as |
| 120 | root.) */ |
| 121 | #define SSH_USER_PERMITTED_KEYS ".ssh/authorized_keys" |
| 122 | |
| 123 | /* Per-user and system-wide ssh "rc" files. These files are executed with |
| 124 | /bin/sh before starting the shell or command if they exist. They |
| 125 | will be passed "proto cookie" as arguments if X11 forwarding with |
| 126 | spoofing is in use. xauth will be run if neither of these exists. */ |
| 127 | #define SSH_USER_RC ".ssh/rc" |
| 128 | #define SSH_SYSTEM_RC ETCDIR "/sshrc" |
| 129 | |
| 130 | /* Ssh-only version of /etc/hosts.equiv. */ |
| 131 | #define SSH_HOSTS_EQUIV ETCDIR "/shosts.equiv" |
| 132 | |
| 133 | /* Additionally, the daemon may use ~/.rhosts and /etc/hosts.equiv if |
| 134 | rhosts authentication is enabled. */ |
| 135 | |
| 136 | /* Name of the environment variable containing the pathname of the |
| 137 | authentication socket. */ |
| 138 | #define SSH_AUTHSOCKET_ENV_NAME "SSH_AUTH_SOCK" |
| 139 | |
Damien Miller | 5eeedae | 1999-10-29 10:21:15 +1000 | [diff] [blame] | 140 | /* Name of the environment variable containing the pathname of the |
| 141 | authentication socket. */ |
| 142 | #define SSH_AGENTPID_ENV_NAME "SSH_AGENT_PID" |
| 143 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 144 | /* Force host key length and server key length to differ by at least this |
| 145 | many bits. This is to make double encryption with rsaref work. */ |
| 146 | #define SSH_KEY_BITS_RESERVED 128 |
| 147 | |
| 148 | /* Length of the session key in bytes. (Specified as 256 bits in the |
| 149 | protocol.) */ |
| 150 | #define SSH_SESSION_KEY_LENGTH 32 |
| 151 | |
| 152 | /* Name of Kerberos service for SSH to use. */ |
| 153 | #define KRB4_SERVICE_NAME "rcmd" |
| 154 | |
| 155 | /* Authentication methods. New types can be added, but old types should not |
| 156 | be removed for compatibility. The maximum allowed value is 31. */ |
| 157 | #define SSH_AUTH_RHOSTS 1 |
| 158 | #define SSH_AUTH_RSA 2 |
| 159 | #define SSH_AUTH_PASSWORD 3 |
| 160 | #define SSH_AUTH_RHOSTS_RSA 4 |
| 161 | /* 5 is TIS */ |
| 162 | #define SSH_AUTH_KERBEROS 6 |
| 163 | #define SSH_PASS_KERBEROS_TGT 7 |
| 164 | /* 8 to 15 are reserved */ |
| 165 | #define SSH_PASS_AFS_TOKEN 21 |
| 166 | |
| 167 | /* Protocol flags. These are bit masks. */ |
| 168 | #define SSH_PROTOFLAG_SCREEN_NUMBER 1 /* X11 forwarding includes screen */ |
| 169 | #define SSH_PROTOFLAG_HOST_IN_FWD_OPEN 2 /* forwarding opens contain host */ |
| 170 | |
| 171 | /* Definition of message types. New values can be added, but old values |
| 172 | should not be removed or without careful consideration of the consequences |
| 173 | for compatibility. The maximum value is 254; value 255 is reserved |
| 174 | for future extension. */ |
| 175 | /* Message name */ /* msg code */ /* arguments */ |
| 176 | #define SSH_MSG_NONE 0 /* no message */ |
| 177 | #define SSH_MSG_DISCONNECT 1 /* cause (string) */ |
| 178 | #define SSH_SMSG_PUBLIC_KEY 2 /* ck,msk,srvk,hostk */ |
| 179 | #define SSH_CMSG_SESSION_KEY 3 /* key (BIGNUM) */ |
| 180 | #define SSH_CMSG_USER 4 /* user (string) */ |
| 181 | #define SSH_CMSG_AUTH_RHOSTS 5 /* user (string) */ |
| 182 | #define SSH_CMSG_AUTH_RSA 6 /* modulus (BIGNUM) */ |
| 183 | #define SSH_SMSG_AUTH_RSA_CHALLENGE 7 /* int (BIGNUM) */ |
| 184 | #define SSH_CMSG_AUTH_RSA_RESPONSE 8 /* int (BIGNUM) */ |
| 185 | #define SSH_CMSG_AUTH_PASSWORD 9 /* pass (string) */ |
| 186 | #define SSH_CMSG_REQUEST_PTY 10 /* TERM, tty modes */ |
| 187 | #define SSH_CMSG_WINDOW_SIZE 11 /* row,col,xpix,ypix */ |
| 188 | #define SSH_CMSG_EXEC_SHELL 12 /* */ |
| 189 | #define SSH_CMSG_EXEC_CMD 13 /* cmd (string) */ |
| 190 | #define SSH_SMSG_SUCCESS 14 /* */ |
| 191 | #define SSH_SMSG_FAILURE 15 /* */ |
| 192 | #define SSH_CMSG_STDIN_DATA 16 /* data (string) */ |
| 193 | #define SSH_SMSG_STDOUT_DATA 17 /* data (string) */ |
| 194 | #define SSH_SMSG_STDERR_DATA 18 /* data (string) */ |
| 195 | #define SSH_CMSG_EOF 19 /* */ |
| 196 | #define SSH_SMSG_EXITSTATUS 20 /* status (int) */ |
| 197 | #define SSH_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* channel (int) */ |
| 198 | #define SSH_MSG_CHANNEL_OPEN_FAILURE 22 /* channel (int) */ |
| 199 | #define SSH_MSG_CHANNEL_DATA 23 /* ch,data (int,str) */ |
| 200 | #define SSH_MSG_CHANNEL_CLOSE 24 /* channel (int) */ |
| 201 | #define SSH_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* channel (int) */ |
| 202 | /* SSH_CMSG_X11_REQUEST_FORWARDING 26 OBSOLETE */ |
| 203 | #define SSH_SMSG_X11_OPEN 27 /* channel (int) */ |
| 204 | #define SSH_CMSG_PORT_FORWARD_REQUEST 28 /* p,host,hp (i,s,i) */ |
| 205 | #define SSH_MSG_PORT_OPEN 29 /* ch,h,p (i,s,i) */ |
| 206 | #define SSH_CMSG_AGENT_REQUEST_FORWARDING 30 /* */ |
| 207 | #define SSH_SMSG_AGENT_OPEN 31 /* port (int) */ |
| 208 | #define SSH_MSG_IGNORE 32 /* string */ |
| 209 | #define SSH_CMSG_EXIT_CONFIRMATION 33 /* */ |
| 210 | #define SSH_CMSG_X11_REQUEST_FORWARDING 34 /* proto,data (s,s) */ |
| 211 | #define SSH_CMSG_AUTH_RHOSTS_RSA 35 /* user,mod (s,mpi) */ |
| 212 | #define SSH_MSG_DEBUG 36 /* string */ |
| 213 | #define SSH_CMSG_REQUEST_COMPRESSION 37 /* level 1-9 (int) */ |
| 214 | #define SSH_CMSG_MAX_PACKET_SIZE 38 /* size 4k-1024k (int) */ |
| 215 | #define SSH_CMSG_AUTH_TIS 39 /* this is proto-1.5, but we ignore TIS */ |
| 216 | #define SSH_SMSG_AUTH_TIS_CHALLENGE 40 |
| 217 | #define SSH_CMSG_AUTH_TIS_RESPONSE 41 |
| 218 | |
| 219 | #define SSH_CMSG_AUTH_KERBEROS 42 /* (KTEXT) */ |
| 220 | #define SSH_SMSG_AUTH_KERBEROS_RESPONSE 43 /* (KTEXT) */ |
| 221 | #define SSH_CMSG_HAVE_KERBEROS_TGT 44 /* credentials (s) */ |
| 222 | #define SSH_CMSG_HAVE_AFS_TOKEN 65 /* token (s) */ |
| 223 | |
| 224 | |
Damien Miller | 5ce662a | 1999-11-11 17:57:39 +1100 | [diff] [blame^] | 225 | /*------------ Definitions for logging. -----------------------*/ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 226 | |
Damien Miller | 5ce662a | 1999-11-11 17:57:39 +1100 | [diff] [blame^] | 227 | /* Supported syslog facilities and levels. */ |
| 228 | typedef enum |
| 229 | { |
| 230 | SYSLOG_FACILITY_DAEMON, |
| 231 | SYSLOG_FACILITY_USER, |
| 232 | SYSLOG_FACILITY_AUTH, |
| 233 | SYSLOG_FACILITY_LOCAL0, |
| 234 | SYSLOG_FACILITY_LOCAL1, |
| 235 | SYSLOG_FACILITY_LOCAL2, |
| 236 | SYSLOG_FACILITY_LOCAL3, |
| 237 | SYSLOG_FACILITY_LOCAL4, |
| 238 | SYSLOG_FACILITY_LOCAL5, |
| 239 | SYSLOG_FACILITY_LOCAL6, |
| 240 | SYSLOG_FACILITY_LOCAL7 |
| 241 | } SyslogFacility; |
| 242 | |
| 243 | typedef enum |
| 244 | { |
| 245 | SYSLOG_LEVEL_QUIET, |
| 246 | SYSLOG_LEVEL_FATAL, |
| 247 | SYSLOG_LEVEL_ERROR, |
| 248 | SYSLOG_LEVEL_INFO, |
| 249 | SYSLOG_LEVEL_CHAT, |
| 250 | SYSLOG_LEVEL_DEBUG |
| 251 | } LogLevel; |
| 252 | |
| 253 | /* Initializes logging. */ |
| 254 | void log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr); |
| 255 | |
| 256 | /* Logging implementation, depending on server or client */ |
| 257 | void do_log(LogLevel level, const char *fmt, va_list args); |
| 258 | |
| 259 | /* Output a message to syslog or stderr */ |
| 260 | void fatal(const char *fmt, ...); |
| 261 | void error(const char *fmt, ...); |
| 262 | void log(const char *fmt, ...); |
| 263 | void chat(const char *fmt, ...); |
| 264 | void debug(const char *fmt, ...); |
| 265 | |
| 266 | /* same as fatal() but w/o logging */ |
| 267 | void fatal_cleanup(void); |
| 268 | |
| 269 | /* Registers a cleanup function to be called by fatal()/fatal_cleanup() before exiting. |
| 270 | It is permissible to call fatal_remove_cleanup for the function itself |
| 271 | from the function. */ |
| 272 | void fatal_add_cleanup(void (*proc)(void *context), void *context); |
| 273 | |
| 274 | /* Removes a cleanup function to be called at fatal(). */ |
| 275 | void fatal_remove_cleanup(void (*proc)(void *context), void *context); |
| 276 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 277 | |
| 278 | /*------------ definitions for login.c -------------*/ |
| 279 | |
| 280 | /* Returns the time when the user last logged in. Returns 0 if the |
| 281 | information is not available. This must be called before record_login. |
| 282 | The host from which the user logged in is stored in buf. */ |
| 283 | unsigned long get_last_login_time(uid_t uid, const char *logname, |
| 284 | char *buf, unsigned int bufsize); |
| 285 | |
| 286 | /* Records that the user has logged in. This does many things normally |
| 287 | done by login(1). */ |
| 288 | void record_login(int pid, const char *ttyname, const char *user, uid_t uid, |
| 289 | const char *host, struct sockaddr_in *addr); |
| 290 | |
| 291 | /* Records that the user has logged out. This does many thigs normally |
| 292 | done by login(1) or init. */ |
| 293 | void record_logout(int pid, const char *ttyname); |
| 294 | |
| 295 | /*------------ definitions for sshconnect.c ----------*/ |
| 296 | |
| 297 | /* Opens a TCP/IP connection to the remote server on the given host. If |
| 298 | port is 0, the default port will be used. If anonymous is zero, |
| 299 | a privileged port will be allocated to make the connection. |
| 300 | This requires super-user privileges if anonymous is false. |
| 301 | Connection_attempts specifies the maximum number of tries, one per |
| 302 | second. This returns true on success, and zero on failure. If the |
| 303 | connection is successful, this calls packet_set_connection for the |
| 304 | connection. */ |
| 305 | int ssh_connect(const char *host, struct sockaddr_in *hostaddr, |
| 306 | int port, int connection_attempts, |
| 307 | int anonymous, uid_t original_real_uid, |
| 308 | const char *proxy_command); |
| 309 | |
| 310 | /* Starts a dialog with the server, and authenticates the current user on the |
| 311 | server. This does not need any extra privileges. The basic connection |
| 312 | to the server must already have been established before this is called. |
| 313 | If login fails, this function prints an error and never returns. |
| 314 | This initializes the random state, and leaves it initialized (it will also |
| 315 | have references from the packet module). */ |
Damien Miller | 5ce662a | 1999-11-11 17:57:39 +1100 | [diff] [blame^] | 316 | |
| 317 | /* for Options */ |
| 318 | #include "readconf.h" |
| 319 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 320 | void ssh_login(int host_key_valid, RSA *host_key, const char *host, |
| 321 | struct sockaddr_in *hostaddr, Options *options, |
| 322 | uid_t original_real_uid); |
| 323 | |
| 324 | /*------------ Definitions for various authentication methods. -------*/ |
| 325 | |
| 326 | /* Tries to authenticate the user using the .rhosts file. Returns true if |
| 327 | authentication succeeds. If ignore_rhosts is non-zero, this will not |
| 328 | consider .rhosts and .shosts (/etc/hosts.equiv will still be used). |
| 329 | If strict_modes is true, checks ownership and modes of .rhosts/.shosts. */ |
| 330 | int auth_rhosts(struct passwd *pw, const char *client_user, |
| 331 | int ignore_rhosts, int strict_modes); |
| 332 | |
| 333 | /* Tries to authenticate the user using the .rhosts file and the host using |
| 334 | its host key. Returns true if authentication succeeds. */ |
| 335 | int auth_rhosts_rsa(struct passwd *pw, const char *client_user, |
| 336 | unsigned int bits, BIGNUM *client_host_key_e, |
| 337 | BIGNUM *client_host_key_n, int ignore_rhosts, |
| 338 | int strict_modes); |
| 339 | |
| 340 | /* Tries to authenticate the user using password. Returns true if |
| 341 | authentication succeeds. */ |
| 342 | int auth_password(struct passwd *pw, const char *password); |
| 343 | |
| 344 | /* Performs the RSA authentication dialog with the client. This returns |
| 345 | 0 if the client could not be authenticated, and 1 if authentication was |
| 346 | successful. This may exit if there is a serious protocol violation. */ |
| 347 | int auth_rsa(struct passwd *pw, BIGNUM *client_n, int strict_modes); |
| 348 | |
| 349 | /* Parses an RSA key (number of bits, e, n) from a string. Moves the pointer |
| 350 | over the key. Skips any whitespace at the beginning and at end. */ |
| 351 | int auth_rsa_read_key(char **cpp, unsigned int *bitsp, BIGNUM *e, BIGNUM *n); |
| 352 | |
| 353 | /* Returns the name of the machine at the other end of the socket. The |
| 354 | returned string should be freed by the caller. */ |
| 355 | char *get_remote_hostname(int socket); |
| 356 | |
| 357 | /* Return the canonical name of the host in the other side of the current |
| 358 | connection (as returned by packet_get_connection). The host name is |
| 359 | cached, so it is efficient to call this several times. */ |
| 360 | const char *get_canonical_hostname(void); |
| 361 | |
| 362 | /* Returns the remote IP address as an ascii string. The value need not be |
| 363 | freed by the caller. */ |
| 364 | const char *get_remote_ipaddr(void); |
| 365 | |
| 366 | /* Returns the port number of the peer of the socket. */ |
| 367 | int get_peer_port(int sock); |
| 368 | |
| 369 | /* Returns the port number of the remote host. */ |
| 370 | int get_remote_port(void); |
| 371 | |
| 372 | /* Tries to match the host name (which must be in all lowercase) against the |
| 373 | comma-separated sequence of subpatterns (each possibly preceded by ! to |
| 374 | indicate negation). Returns true if there is a positive match; zero |
| 375 | otherwise. */ |
| 376 | int match_hostname(const char *host, const char *pattern, unsigned int len); |
| 377 | |
| 378 | /* Checks whether the given host is already in the list of our known hosts. |
| 379 | Returns HOST_OK if the host is known and has the specified key, |
| 380 | HOST_NEW if the host is not known, and HOST_CHANGED if the host is known |
| 381 | but used to have a different host key. The host must be in all lowercase. */ |
| 382 | typedef enum { HOST_OK, HOST_NEW, HOST_CHANGED } HostStatus; |
| 383 | HostStatus check_host_in_hostfile(const char *filename, |
| 384 | const char *host, unsigned int bits, |
| 385 | BIGNUM *e, BIGNUM *n, |
| 386 | BIGNUM *ke, BIGNUM *kn); |
| 387 | |
| 388 | /* Appends an entry to the host file. Returns false if the entry |
| 389 | could not be appended. */ |
| 390 | int add_host_to_hostfile(const char *filename, const char *host, |
| 391 | unsigned int bits, BIGNUM *e, BIGNUM *n); |
| 392 | |
| 393 | /* Performs the RSA authentication challenge-response dialog with the client, |
| 394 | and returns true (non-zero) if the client gave the correct answer to |
| 395 | our challenge; returns zero if the client gives a wrong answer. */ |
| 396 | int auth_rsa_challenge_dialog(unsigned int bits, BIGNUM *e, BIGNUM *n); |
| 397 | |
| 398 | /* Reads a passphrase from /dev/tty with echo turned off. Returns the |
| 399 | passphrase (allocated with xmalloc). Exits if EOF is encountered. |
| 400 | If from_stdin is true, the passphrase will be read from stdin instead. */ |
| 401 | char *read_passphrase(const char *prompt, int from_stdin); |
| 402 | |
| 403 | /* Saves the authentication (private) key in a file, encrypting it with |
| 404 | passphrase. The identification of the file (lowest 64 bits of n) |
| 405 | will precede the key to provide identification of the key without |
| 406 | needing a passphrase. */ |
| 407 | int save_private_key(const char *filename, const char *passphrase, |
| 408 | RSA *private_key, const char *comment); |
| 409 | |
| 410 | /* Loads the public part of the key file (public key and comment). |
| 411 | Returns 0 if an error occurred; zero if the public key was successfully |
| 412 | read. The comment of the key is returned in comment_return if it is |
| 413 | non-NULL; the caller must free the value with xfree. */ |
| 414 | int load_public_key(const char *filename, RSA *pub, |
| 415 | char **comment_return); |
| 416 | |
| 417 | /* Loads the private key from the file. Returns 0 if an error is encountered |
| 418 | (file does not exist or is not readable, or passphrase is bad). |
| 419 | This initializes the private key. The comment of the key is returned |
| 420 | in comment_return if it is non-NULL; the caller must free the value |
| 421 | with xfree. */ |
| 422 | int load_private_key(const char *filename, const char *passphrase, |
| 423 | RSA *private_key, char **comment_return); |
| 424 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 425 | /*---------------- definitions for channels ------------------*/ |
| 426 | |
| 427 | /* Sets specific protocol options. */ |
| 428 | void channel_set_options(int hostname_in_open); |
| 429 | |
| 430 | /* Allocate a new channel object and set its type and socket. Remote_name |
| 431 | must have been allocated with xmalloc; this will free it when the channel |
| 432 | is freed. */ |
| 433 | int channel_allocate(int type, int sock, char *remote_name); |
| 434 | |
| 435 | /* Free the channel and close its socket. */ |
| 436 | void channel_free(int channel); |
| 437 | |
| 438 | /* Add any bits relevant to channels in select bitmasks. */ |
| 439 | void channel_prepare_select(fd_set *readset, fd_set *writeset); |
| 440 | |
| 441 | /* After select, perform any appropriate operations for channels which |
| 442 | have events pending. */ |
| 443 | void channel_after_select(fd_set *readset, fd_set *writeset); |
| 444 | |
| 445 | /* If there is data to send to the connection, send some of it now. */ |
| 446 | void channel_output_poll(void); |
| 447 | |
| 448 | /* This is called when a packet of type CHANNEL_DATA has just been received. |
| 449 | The message type has already been consumed, but channel number and data |
| 450 | is still there. */ |
| 451 | void channel_input_data(int payload_len); |
| 452 | |
| 453 | /* Returns true if no channel has too much buffered data. */ |
| 454 | int channel_not_very_much_buffered_data(void); |
| 455 | |
| 456 | /* This is called after receiving CHANNEL_CLOSE. */ |
| 457 | void channel_input_close(void); |
| 458 | |
| 459 | /* This is called after receiving CHANNEL_CLOSE_CONFIRMATION. */ |
| 460 | void channel_input_close_confirmation(void); |
| 461 | |
| 462 | /* This is called after receiving CHANNEL_OPEN_CONFIRMATION. */ |
| 463 | void channel_input_open_confirmation(void); |
| 464 | |
| 465 | /* This is called after receiving CHANNEL_OPEN_FAILURE from the other side. */ |
| 466 | void channel_input_open_failure(void); |
| 467 | |
| 468 | /* This closes any sockets that are listening for connections; this removes |
| 469 | any unix domain sockets. */ |
| 470 | void channel_stop_listening(void); |
| 471 | |
| 472 | /* Closes the sockets of all channels. This is used to close extra file |
| 473 | descriptors after a fork. */ |
| 474 | void channel_close_all(void); |
| 475 | |
| 476 | /* Returns the maximum file descriptor number used by the channels. */ |
| 477 | int channel_max_fd(void); |
| 478 | |
| 479 | /* Returns true if there is still an open channel over the connection. */ |
| 480 | int channel_still_open(void); |
| 481 | |
| 482 | /* Returns a string containing a list of all open channels. The list is |
| 483 | suitable for displaying to the user. It uses crlf instead of newlines. |
| 484 | The caller should free the string with xfree. */ |
| 485 | char *channel_open_message(void); |
| 486 | |
| 487 | /* Initiate forwarding of connections to local port "port" through the secure |
| 488 | channel to host:port from remote side. This never returns if there |
| 489 | was an error. */ |
| 490 | void channel_request_local_forwarding(int port, const char *host, |
| 491 | int remote_port); |
| 492 | |
| 493 | /* Initiate forwarding of connections to port "port" on remote host through |
| 494 | the secure channel to host:port from local side. This never returns |
| 495 | if there was an error. This registers that open requests for that |
| 496 | port are permitted. */ |
| 497 | void channel_request_remote_forwarding(int port, const char *host, |
| 498 | int remote_port); |
| 499 | |
| 500 | /* Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually |
| 501 | called by the server, because the user could connect to any port anyway, |
| 502 | and the server has no way to know but to trust the client anyway. */ |
| 503 | void channel_permit_all_opens(void); |
| 504 | |
| 505 | /* This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates |
| 506 | listening for the port, and sends back a success reply (or disconnect |
| 507 | message if there was an error). This never returns if there was an |
| 508 | error. */ |
| 509 | void channel_input_port_forward_request(int is_root); |
| 510 | |
| 511 | /* This is called after receiving PORT_OPEN message. This attempts to connect |
| 512 | to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION or |
| 513 | CHANNEL_OPEN_FAILURE. */ |
| 514 | void channel_input_port_open(int payload_len); |
| 515 | |
| 516 | /* Creates a port for X11 connections, and starts listening for it. |
| 517 | Returns the display name, or NULL if an error was encountered. */ |
| 518 | char *x11_create_display(int screen); |
| 519 | |
| 520 | /* Creates an internet domain socket for listening for X11 connections. |
| 521 | Returns a suitable value for the DISPLAY variable, or NULL if an error |
| 522 | occurs. */ |
| 523 | char *x11_create_display_inet(int screen); |
| 524 | |
| 525 | /* This is called when SSH_SMSG_X11_OPEN is received. The packet contains |
| 526 | the remote channel number. We should do whatever we want, and respond |
| 527 | with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. */ |
| 528 | void x11_input_open(int payload_len); |
| 529 | |
| 530 | /* Requests forwarding of X11 connections. This should be called on the |
| 531 | client only. */ |
| 532 | void x11_request_forwarding(void); |
| 533 | |
| 534 | /* Requests forwarding for X11 connections, with authentication spoofing. |
| 535 | This should be called in the client only. */ |
| 536 | void x11_request_forwarding_with_spoofing(const char *proto, const char *data); |
| 537 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 538 | /* Sends a message to the server to request authentication fd forwarding. */ |
| 539 | void auth_request_forwarding(void); |
| 540 | |
| 541 | /* Returns the name of the forwarded authentication socket. Returns NULL |
| 542 | if there is no forwarded authentication socket. The returned value points |
| 543 | to a static buffer. */ |
| 544 | char *auth_get_socket_name(void); |
| 545 | |
| 546 | /* This if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
| 547 | This starts forwarding authentication requests. */ |
| 548 | void auth_input_request_forwarding(struct passwd *pw); |
| 549 | |
| 550 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ |
| 551 | void auth_input_open_request(void); |
| 552 | |
| 553 | /* Returns true if the given string matches the pattern (which may contain |
| 554 | ? and * as wildcards), and zero if it does not match. */ |
| 555 | int match_pattern(const char *s, const char *pattern); |
| 556 | |
| 557 | /* Expands tildes in the file name. Returns data allocated by xmalloc. |
| 558 | Warning: this calls getpw*. */ |
| 559 | char *tilde_expand_filename(const char *filename, uid_t my_uid); |
| 560 | |
| 561 | /* Performs the interactive session. This handles data transmission between |
| 562 | the client and the program. Note that the notion of stdin, stdout, and |
| 563 | stderr in this function is sort of reversed: this function writes to |
| 564 | stdin (of the child program), and reads from stdout and stderr (of the |
| 565 | child program). */ |
| 566 | void server_loop(int pid, int fdin, int fdout, int fderr); |
| 567 | |
| 568 | /* Client side main loop for the interactive session. */ |
| 569 | int client_loop(int have_pty, int escape_char); |
| 570 | |
| 571 | /* Linked list of custom environment strings (see auth-rsa.c). */ |
| 572 | struct envstring { |
| 573 | struct envstring *next; |
| 574 | char *s; |
| 575 | }; |
| 576 | |
| 577 | #ifdef KRB4 |
| 578 | #include <krb.h> |
| 579 | |
| 580 | /* Performs Kerberos v4 mutual authentication with the client. This returns |
| 581 | 0 if the client could not be authenticated, and 1 if authentication was |
| 582 | successful. This may exit if there is a serious protocol violation. */ |
| 583 | int auth_krb4(const char *server_user, KTEXT auth, char **client); |
Damien Miller | 5ce662a | 1999-11-11 17:57:39 +1100 | [diff] [blame^] | 584 | int krb4_init(uid_t uid); |
| 585 | void krb4_cleanup_proc(void *ignore); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 586 | |
| 587 | #ifdef AFS |
| 588 | #include <kafs.h> |
| 589 | |
| 590 | /* Accept passed Kerberos v4 ticket-granting ticket and AFS tokens. */ |
| 591 | int auth_kerberos_tgt(struct passwd *pw, const char *string); |
Damien Miller | fd7c911 | 1999-11-08 16:15:55 +1100 | [diff] [blame] | 592 | int auth_afs_token(struct passwd *pw, const char *token_string); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 593 | |
| 594 | int creds_to_radix(CREDENTIALS *creds, unsigned char *buf); |
| 595 | int radix_to_creds(const char *buf, CREDENTIALS *creds); |
| 596 | #endif /* AFS */ |
| 597 | |
| 598 | #endif /* KRB4 */ |
| 599 | |
| 600 | #ifdef SKEY |
| 601 | #include <skey.h> |
| 602 | char *skey_fake_keyinfo(char *username); |
| 603 | #endif /* SKEY */ |
| 604 | |
| 605 | #endif /* SSH_H */ |