ssh.h revision 57429
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 16/* RCSID("$Id: ssh.h,v 1.33 2000/02/01 22:32:53 d Exp $"); */ 17 18#ifndef SSH_H 19#define SSH_H 20 21#include "rsa.h" 22#include "cipher.h" 23 24/* 25 * The default cipher used if IDEA is not supported by the remote host. It is 26 * recommended that this be one of the mandatory ciphers (DES, 3DES), though 27 * that is not required. 28 */ 29#define SSH_FALLBACK_CIPHER SSH_CIPHER_3DES 30 31/* Cipher used for encrypting authentication files. */ 32#define SSH_AUTHFILE_CIPHER SSH_CIPHER_3DES 33 34/* Default port number. */ 35#define SSH_DEFAULT_PORT 22 36 37/* Maximum number of TCP/IP ports forwarded per direction. */ 38#define SSH_MAX_FORWARDS_PER_DIRECTION 100 39 40/* 41 * Maximum number of RSA authentication identity files that can be specified 42 * in configuration files or on the command line. 43 */ 44#define SSH_MAX_IDENTITY_FILES 100 45 46/* 47 * Major protocol version. Different version indicates major incompatiblity 48 * that prevents communication. 49 */ 50#define PROTOCOL_MAJOR 1 51 52/* 53 * Minor protocol version. Different version indicates minor incompatibility 54 * that does not prevent interoperation. 55 */ 56#define PROTOCOL_MINOR 5 57 58/* 59 * Name for the service. The port named by this service overrides the 60 * default port if present. 61 */ 62#define SSH_SERVICE_NAME "ssh" 63 64#define ETCDIR "/etc" 65#define PIDDIR "/var/run" 66 67/* 68 * System-wide file containing host keys of known hosts. This file should be 69 * world-readable. 70 */ 71#define SSH_SYSTEM_HOSTFILE ETCDIR "/ssh_known_hosts" 72 73/* 74 * Of these, ssh_host_key must be readable only by root, whereas ssh_config 75 * should be world-readable. 76 */ 77#define HOST_KEY_FILE ETCDIR "/ssh_host_key" 78#define SERVER_CONFIG_FILE ETCDIR "/sshd_config" 79#define HOST_CONFIG_FILE ETCDIR "/ssh_config" 80 81#define SSH_PROGRAM "/usr/bin/ssh" 82 83/* 84 * The process id of the daemon listening for connections is saved here to 85 * make it easier to kill the correct daemon when necessary. 86 */ 87#define SSH_DAEMON_PID_FILE PIDDIR "/sshd.pid" 88 89/* 90 * The directory in user\'s home directory in which the files reside. The 91 * directory should be world-readable (though not all files are). 92 */ 93#define SSH_USER_DIR ".ssh" 94 95/* 96 * Per-user file containing host keys of known hosts. This file need not be 97 * readable by anyone except the user him/herself, though this does not 98 * contain anything particularly secret. 99 */ 100#define SSH_USER_HOSTFILE "~/.ssh/known_hosts" 101 102/* 103 * Name of the default file containing client-side authentication key. This 104 * file should only be readable by the user him/herself. 105 */ 106#define SSH_CLIENT_IDENTITY ".ssh/identity" 107 108/* 109 * Configuration file in user\'s home directory. This file need not be 110 * readable by anyone but the user him/herself, but does not contain anything 111 * particularly secret. If the user\'s home directory resides on an NFS 112 * volume where root is mapped to nobody, this may need to be world-readable. 113 */ 114#define SSH_USER_CONFFILE ".ssh/config" 115 116/* 117 * File containing a list of those rsa keys that permit logging in as this 118 * user. This file need not be readable by anyone but the user him/herself, 119 * but does not contain anything particularly secret. If the user\'s home 120 * directory resides on an NFS volume where root is mapped to nobody, this 121 * may need to be world-readable. (This file is read by the daemon which is 122 * running as root.) 123 */ 124#define SSH_USER_PERMITTED_KEYS ".ssh/authorized_keys" 125 126/* 127 * Per-user and system-wide ssh "rc" files. These files are executed with 128 * /bin/sh before starting the shell or command if they exist. They will be 129 * passed "proto cookie" as arguments if X11 forwarding with spoofing is in 130 * use. xauth will be run if neither of these exists. 131 */ 132#define SSH_USER_RC ".ssh/rc" 133#define SSH_SYSTEM_RC ETCDIR "/sshrc" 134 135/* 136 * Ssh-only version of /etc/hosts.equiv. Additionally, the daemon may use 137 * ~/.rhosts and /etc/hosts.equiv if rhosts authentication is enabled. 138 */ 139#define SSH_HOSTS_EQUIV ETCDIR "/shosts.equiv" 140 141/* 142 * Name of the environment variable containing the pathname of the 143 * authentication socket. 144 */ 145#define SSH_AUTHSOCKET_ENV_NAME "SSH_AUTH_SOCK" 146 147/* 148 * Name of the environment variable containing the pathname of the 149 * authentication socket. 150 */ 151#define SSH_AGENTPID_ENV_NAME "SSH_AGENT_PID" 152 153/* 154 * Default path to ssh-askpass used by ssh-add, 155 * environment variable for overwriting the default location 156 */ 157#define SSH_ASKPASS_DEFAULT "/usr/X11R6/bin/ssh-askpass" 158#define SSH_ASKPASS_ENV "SSH_ASKPASS" 159 160/* 161 * Force host key length and server key length to differ by at least this 162 * many bits. This is to make double encryption with rsaref work. 163 */ 164#define SSH_KEY_BITS_RESERVED 128 165 166/* 167 * Length of the session key in bytes. (Specified as 256 bits in the 168 * protocol.) 169 */ 170#define SSH_SESSION_KEY_LENGTH 32 171 172/* Name of Kerberos service for SSH to use. */ 173#define KRB4_SERVICE_NAME "rcmd" 174 175/* 176 * Authentication methods. New types can be added, but old types should not 177 * be removed for compatibility. The maximum allowed value is 31. 178 */ 179#define SSH_AUTH_RHOSTS 1 180#define SSH_AUTH_RSA 2 181#define SSH_AUTH_PASSWORD 3 182#define SSH_AUTH_RHOSTS_RSA 4 183#define SSH_AUTH_TIS 5 184#define SSH_AUTH_KERBEROS 6 185#define SSH_PASS_KERBEROS_TGT 7 186 /* 8 to 15 are reserved */ 187#define SSH_PASS_AFS_TOKEN 21 188 189/* Protocol flags. These are bit masks. */ 190#define SSH_PROTOFLAG_SCREEN_NUMBER 1 /* X11 forwarding includes screen */ 191#define SSH_PROTOFLAG_HOST_IN_FWD_OPEN 2 /* forwarding opens contain host */ 192 193/* 194 * Definition of message types. New values can be added, but old values 195 * should not be removed or without careful consideration of the consequences 196 * for compatibility. The maximum value is 254; value 255 is reserved for 197 * future extension. 198 */ 199/* Message name */ /* msg code */ /* arguments */ 200#define SSH_MSG_NONE 0 /* no message */ 201#define SSH_MSG_DISCONNECT 1 /* cause (string) */ 202#define SSH_SMSG_PUBLIC_KEY 2 /* ck,msk,srvk,hostk */ 203#define SSH_CMSG_SESSION_KEY 3 /* key (BIGNUM) */ 204#define SSH_CMSG_USER 4 /* user (string) */ 205#define SSH_CMSG_AUTH_RHOSTS 5 /* user (string) */ 206#define SSH_CMSG_AUTH_RSA 6 /* modulus (BIGNUM) */ 207#define SSH_SMSG_AUTH_RSA_CHALLENGE 7 /* int (BIGNUM) */ 208#define SSH_CMSG_AUTH_RSA_RESPONSE 8 /* int (BIGNUM) */ 209#define SSH_CMSG_AUTH_PASSWORD 9 /* pass (string) */ 210#define SSH_CMSG_REQUEST_PTY 10 /* TERM, tty modes */ 211#define SSH_CMSG_WINDOW_SIZE 11 /* row,col,xpix,ypix */ 212#define SSH_CMSG_EXEC_SHELL 12 /* */ 213#define SSH_CMSG_EXEC_CMD 13 /* cmd (string) */ 214#define SSH_SMSG_SUCCESS 14 /* */ 215#define SSH_SMSG_FAILURE 15 /* */ 216#define SSH_CMSG_STDIN_DATA 16 /* data (string) */ 217#define SSH_SMSG_STDOUT_DATA 17 /* data (string) */ 218#define SSH_SMSG_STDERR_DATA 18 /* data (string) */ 219#define SSH_CMSG_EOF 19 /* */ 220#define SSH_SMSG_EXITSTATUS 20 /* status (int) */ 221#define SSH_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* channel (int) */ 222#define SSH_MSG_CHANNEL_OPEN_FAILURE 22 /* channel (int) */ 223#define SSH_MSG_CHANNEL_DATA 23 /* ch,data (int,str) */ 224#define SSH_MSG_CHANNEL_CLOSE 24 /* channel (int) */ 225#define SSH_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* channel (int) */ 226/* SSH_CMSG_X11_REQUEST_FORWARDING 26 OBSOLETE */ 227#define SSH_SMSG_X11_OPEN 27 /* channel (int) */ 228#define SSH_CMSG_PORT_FORWARD_REQUEST 28 /* p,host,hp (i,s,i) */ 229#define SSH_MSG_PORT_OPEN 29 /* ch,h,p (i,s,i) */ 230#define SSH_CMSG_AGENT_REQUEST_FORWARDING 30 /* */ 231#define SSH_SMSG_AGENT_OPEN 31 /* port (int) */ 232#define SSH_MSG_IGNORE 32 /* string */ 233#define SSH_CMSG_EXIT_CONFIRMATION 33 /* */ 234#define SSH_CMSG_X11_REQUEST_FORWARDING 34 /* proto,data (s,s) */ 235#define SSH_CMSG_AUTH_RHOSTS_RSA 35 /* user,mod (s,mpi) */ 236#define SSH_MSG_DEBUG 36 /* string */ 237#define SSH_CMSG_REQUEST_COMPRESSION 37 /* level 1-9 (int) */ 238#define SSH_CMSG_MAX_PACKET_SIZE 38 /* size 4k-1024k (int) */ 239#define SSH_CMSG_AUTH_TIS 39 /* we use this for s/key */ 240#define SSH_SMSG_AUTH_TIS_CHALLENGE 40 /* challenge (string) */ 241#define SSH_CMSG_AUTH_TIS_RESPONSE 41 /* response (string) */ 242#define SSH_CMSG_AUTH_KERBEROS 42 /* (KTEXT) */ 243#define SSH_SMSG_AUTH_KERBEROS_RESPONSE 43 /* (KTEXT) */ 244#define SSH_CMSG_HAVE_KERBEROS_TGT 44 /* credentials (s) */ 245#define SSH_CMSG_HAVE_AFS_TOKEN 65 /* token (s) */ 246 247/*------------ definitions for login.c -------------*/ 248 249/* 250 * Returns the time when the user last logged in. Returns 0 if the 251 * information is not available. This must be called before record_login. 252 * The host from which the user logged in is stored in buf. 253 */ 254unsigned long 255get_last_login_time(uid_t uid, const char *logname, 256 char *buf, unsigned int bufsize); 257 258/* 259 * Records that the user has logged in. This does many things normally done 260 * by login(1). 261 */ 262void 263record_login(int pid, const char *ttyname, const char *user, uid_t uid, 264 const char *host, struct sockaddr *addr); 265 266/* 267 * Records that the user has logged out. This does many thigs normally done 268 * by login(1) or init. 269 */ 270void record_logout(int pid, const char *ttyname); 271 272/*------------ definitions for sshconnect.c ----------*/ 273 274/* 275 * Opens a TCP/IP connection to the remote server on the given host. If port 276 * is 0, the default port will be used. If anonymous is zero, a privileged 277 * port will be allocated to make the connection. This requires super-user 278 * privileges if anonymous is false. Connection_attempts specifies the 279 * maximum number of tries, one per second. This returns true on success, 280 * and zero on failure. If the connection is successful, this calls 281 * packet_set_connection for the connection. 282 */ 283int 284ssh_connect(const char *host, struct sockaddr_storage * hostaddr, 285 u_short port, int connection_attempts, 286 int anonymous, uid_t original_real_uid, 287 const char *proxy_command); 288 289/* 290 * Starts a dialog with the server, and authenticates the current user on the 291 * server. This does not need any extra privileges. The basic connection to 292 * the server must already have been established before this is called. If 293 * login fails, this function prints an error and never returns. This 294 * initializes the random state, and leaves it initialized (it will also have 295 * references from the packet module). 296 */ 297 298void 299ssh_login(int host_key_valid, RSA * host_key, const char *host, 300 struct sockaddr * hostaddr, uid_t original_real_uid); 301 302/*------------ Definitions for various authentication methods. -------*/ 303 304/* 305 * Tries to authenticate the user using the .rhosts file. Returns true if 306 * authentication succeeds. If ignore_rhosts is non-zero, this will not 307 * consider .rhosts and .shosts (/etc/hosts.equiv will still be used). 308 */ 309int auth_rhosts(struct passwd * pw, const char *client_user); 310 311/* 312 * Tries to authenticate the user using the .rhosts file and the host using 313 * its host key. Returns true if authentication succeeds. 314 */ 315int 316auth_rhosts_rsa(struct passwd * pw, const char *client_user, 317 BIGNUM * client_host_key_e, BIGNUM * client_host_key_n); 318 319/* 320 * Tries to authenticate the user using password. Returns true if 321 * authentication succeeds. 322 */ 323int auth_password(struct passwd * pw, const char *password); 324 325/* 326 * Performs the RSA authentication dialog with the client. This returns 0 if 327 * the client could not be authenticated, and 1 if authentication was 328 * successful. This may exit if there is a serious protocol violation. 329 */ 330int auth_rsa(struct passwd * pw, BIGNUM * client_n); 331 332/* 333 * Parses an RSA key (number of bits, e, n) from a string. Moves the pointer 334 * over the key. Skips any whitespace at the beginning and at end. 335 */ 336int auth_rsa_read_key(char **cpp, unsigned int *bitsp, BIGNUM * e, BIGNUM * n); 337 338/* 339 * Returns the name of the machine at the other end of the socket. The 340 * returned string should be freed by the caller. 341 */ 342char *get_remote_hostname(int socket); 343 344/* 345 * Return the canonical name of the host in the other side of the current 346 * connection (as returned by packet_get_connection). The host name is 347 * cached, so it is efficient to call this several times. 348 */ 349const char *get_canonical_hostname(void); 350 351/* 352 * Returns the remote IP address as an ascii string. The value need not be 353 * freed by the caller. 354 */ 355const char *get_remote_ipaddr(void); 356 357/* Returns the port number of the peer of the socket. */ 358int get_peer_port(int sock); 359 360/* Returns the port number of the remote/local host. */ 361int get_remote_port(void); 362int get_local_port(void); 363 364 365/* 366 * Tries to match the host name (which must be in all lowercase) against the 367 * comma-separated sequence of subpatterns (each possibly preceded by ! to 368 * indicate negation). Returns true if there is a positive match; zero 369 * otherwise. 370 */ 371int match_hostname(const char *host, const char *pattern, unsigned int len); 372 373/* 374 * Checks whether the given host is already in the list of our known hosts. 375 * Returns HOST_OK if the host is known and has the specified key, HOST_NEW 376 * if the host is not known, and HOST_CHANGED if the host is known but used 377 * to have a different host key. The host must be in all lowercase. 378 */ 379typedef enum { 380 HOST_OK, HOST_NEW, HOST_CHANGED 381} HostStatus; 382HostStatus 383check_host_in_hostfile(const char *filename, const char *host, 384 BIGNUM * e, BIGNUM * n, BIGNUM * ke, BIGNUM * kn); 385 386/* 387 * Appends an entry to the host file. Returns false if the entry could not 388 * be appended. 389 */ 390int 391add_host_to_hostfile(const char *filename, const char *host, 392 BIGNUM * e, BIGNUM * n); 393 394/* 395 * Performs the RSA authentication challenge-response dialog with the client, 396 * and returns true (non-zero) if the client gave the correct answer to our 397 * challenge; returns zero if the client gives a wrong answer. 398 */ 399int auth_rsa_challenge_dialog(BIGNUM * e, BIGNUM * n); 400 401/* 402 * Reads a passphrase from /dev/tty with echo turned off. Returns the 403 * passphrase (allocated with xmalloc). Exits if EOF is encountered. If 404 * from_stdin is true, the passphrase will be read from stdin instead. 405 */ 406char *read_passphrase(const char *prompt, int from_stdin); 407 408/* 409 * Saves the authentication (private) key in a file, encrypting it with 410 * passphrase. The identification of the file (lowest 64 bits of n) will 411 * precede the key to provide identification of the key without needing a 412 * passphrase. 413 */ 414int 415save_private_key(const char *filename, const char *passphrase, 416 RSA * private_key, const char *comment); 417 418/* 419 * Loads the public part of the key file (public key and comment). Returns 0 420 * if an error occurred; zero if the public key was successfully read. The 421 * comment of the key is returned in comment_return if it is non-NULL; the 422 * caller must free the value with xfree. 423 */ 424int 425load_public_key(const char *filename, RSA * pub, 426 char **comment_return); 427 428/* 429 * Loads the private key from the file. Returns 0 if an error is encountered 430 * (file does not exist or is not readable, or passphrase is bad). This 431 * initializes the private key. The comment of the key is returned in 432 * comment_return if it is non-NULL; the caller must free the value with 433 * xfree. 434 */ 435int 436load_private_key(const char *filename, const char *passphrase, 437 RSA * private_key, char **comment_return); 438 439/*------------ Definitions for logging. -----------------------*/ 440 441/* Supported syslog facilities and levels. */ 442typedef enum { 443 SYSLOG_FACILITY_DAEMON, 444 SYSLOG_FACILITY_USER, 445 SYSLOG_FACILITY_AUTH, 446 SYSLOG_FACILITY_LOCAL0, 447 SYSLOG_FACILITY_LOCAL1, 448 SYSLOG_FACILITY_LOCAL2, 449 SYSLOG_FACILITY_LOCAL3, 450 SYSLOG_FACILITY_LOCAL4, 451 SYSLOG_FACILITY_LOCAL5, 452 SYSLOG_FACILITY_LOCAL6, 453 SYSLOG_FACILITY_LOCAL7 454} SyslogFacility; 455 456typedef enum { 457 SYSLOG_LEVEL_QUIET, 458 SYSLOG_LEVEL_FATAL, 459 SYSLOG_LEVEL_ERROR, 460 SYSLOG_LEVEL_INFO, 461 SYSLOG_LEVEL_VERBOSE, 462 SYSLOG_LEVEL_DEBUG 463} LogLevel; 464/* Initializes logging. */ 465void log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr); 466 467/* Logging implementation, depending on server or client */ 468void do_log(LogLevel level, const char *fmt, va_list args); 469 470/* name to facility/level */ 471SyslogFacility log_facility_number(char *name); 472LogLevel log_level_number(char *name); 473 474/* Output a message to syslog or stderr */ 475void fatal(const char *fmt,...) __attribute__((format(printf, 1, 2))); 476void error(const char *fmt,...) __attribute__((format(printf, 1, 2))); 477void log(const char *fmt,...) __attribute__((format(printf, 1, 2))); 478void verbose(const char *fmt,...) __attribute__((format(printf, 1, 2))); 479void debug(const char *fmt,...) __attribute__((format(printf, 1, 2))); 480 481/* same as fatal() but w/o logging */ 482void fatal_cleanup(void); 483 484/* 485 * Registers a cleanup function to be called by fatal()/fatal_cleanup() 486 * before exiting. It is permissible to call fatal_remove_cleanup for the 487 * function itself from the function. 488 */ 489void fatal_add_cleanup(void (*proc) (void *context), void *context); 490 491/* Removes a cleanup function to be called at fatal(). */ 492void fatal_remove_cleanup(void (*proc) (void *context), void *context); 493 494/*---------------- definitions for channels ------------------*/ 495 496/* Sets specific protocol options. */ 497void channel_set_options(int hostname_in_open); 498 499/* 500 * Allocate a new channel object and set its type and socket. Remote_name 501 * must have been allocated with xmalloc; this will free it when the channel 502 * is freed. 503 */ 504int channel_allocate(int type, int sock, char *remote_name); 505 506/* Free the channel and close its socket. */ 507void channel_free(int channel); 508 509/* Add any bits relevant to channels in select bitmasks. */ 510void channel_prepare_select(fd_set * readset, fd_set * writeset); 511 512/* 513 * After select, perform any appropriate operations for channels which have 514 * events pending. 515 */ 516void channel_after_select(fd_set * readset, fd_set * writeset); 517 518/* If there is data to send to the connection, send some of it now. */ 519void channel_output_poll(void); 520 521/* 522 * This is called when a packet of type CHANNEL_DATA has just been received. 523 * The message type has already been consumed, but channel number and data is 524 * still there. 525 */ 526void channel_input_data(int payload_len); 527 528/* Returns true if no channel has too much buffered data. */ 529int channel_not_very_much_buffered_data(void); 530 531/* This is called after receiving CHANNEL_CLOSE. */ 532void channel_input_close(void); 533 534/* This is called after receiving CHANNEL_CLOSE_CONFIRMATION. */ 535void channel_input_close_confirmation(void); 536 537/* This is called after receiving CHANNEL_OPEN_CONFIRMATION. */ 538void channel_input_open_confirmation(void); 539 540/* This is called after receiving CHANNEL_OPEN_FAILURE from the other side. */ 541void channel_input_open_failure(void); 542 543/* This closes any sockets that are listening for connections; this removes 544 any unix domain sockets. */ 545void channel_stop_listening(void); 546 547/* 548 * Closes the sockets of all channels. This is used to close extra file 549 * descriptors after a fork. 550 */ 551void channel_close_all(void); 552 553/* Returns the maximum file descriptor number used by the channels. */ 554int channel_max_fd(void); 555 556/* Returns true if there is still an open channel over the connection. */ 557int channel_still_open(void); 558 559/* 560 * Returns a string containing a list of all open channels. The list is 561 * suitable for displaying to the user. It uses crlf instead of newlines. 562 * The caller should free the string with xfree. 563 */ 564char *channel_open_message(void); 565 566/* 567 * Initiate forwarding of connections to local port "port" through the secure 568 * channel to host:port from remote side. This never returns if there was an 569 * error. 570 */ 571void 572channel_request_local_forwarding(u_short port, const char *host, 573 u_short remote_port, int gateway_ports); 574 575/* 576 * Initiate forwarding of connections to port "port" on remote host through 577 * the secure channel to host:port from local side. This never returns if 578 * there was an error. This registers that open requests for that port are 579 * permitted. 580 */ 581void 582channel_request_remote_forwarding(u_short port, const char *host, 583 u_short remote_port); 584 585/* 586 * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually 587 * called by the server, because the user could connect to any port anyway, 588 * and the server has no way to know but to trust the client anyway. 589 */ 590void channel_permit_all_opens(void); 591 592/* 593 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates 594 * listening for the port, and sends back a success reply (or disconnect 595 * message if there was an error). This never returns if there was an error. 596 */ 597void channel_input_port_forward_request(int is_root); 598 599/* 600 * This is called after receiving PORT_OPEN message. This attempts to 601 * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION 602 * or CHANNEL_OPEN_FAILURE. 603 */ 604void channel_input_port_open(int payload_len); 605 606/* 607 * Creates a port for X11 connections, and starts listening for it. Returns 608 * the display name, or NULL if an error was encountered. 609 */ 610char *x11_create_display(int screen); 611 612/* 613 * Creates an internet domain socket for listening for X11 connections. 614 * Returns a suitable value for the DISPLAY variable, or NULL if an error 615 * occurs. 616 */ 617char *x11_create_display_inet(int screen, int x11_display_offset); 618 619/* 620 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains 621 * the remote channel number. We should do whatever we want, and respond 622 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. 623 */ 624void x11_input_open(int payload_len); 625 626/* 627 * Requests forwarding of X11 connections. This should be called on the 628 * client only. 629 */ 630void x11_request_forwarding(void); 631 632/* 633 * Requests forwarding for X11 connections, with authentication spoofing. 634 * This should be called in the client only. 635 */ 636void x11_request_forwarding_with_spoofing(const char *proto, const char *data); 637 638/* Sends a message to the server to request authentication fd forwarding. */ 639void auth_request_forwarding(void); 640 641/* 642 * Returns the name of the forwarded authentication socket. Returns NULL if 643 * there is no forwarded authentication socket. The returned value points to 644 * a static buffer. 645 */ 646char *auth_get_socket_name(void); 647 648/* 649 * This if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. 650 * This starts forwarding authentication requests. 651 */ 652void auth_input_request_forwarding(struct passwd * pw); 653 654/* This is called to process an SSH_SMSG_AGENT_OPEN message. */ 655void auth_input_open_request(void); 656 657/* 658 * Returns true if the given string matches the pattern (which may contain ? 659 * and * as wildcards), and zero if it does not match. 660 */ 661int match_pattern(const char *s, const char *pattern); 662 663/* 664 * Expands tildes in the file name. Returns data allocated by xmalloc. 665 * Warning: this calls getpw*. 666 */ 667char *tilde_expand_filename(const char *filename, uid_t my_uid); 668 669/* 670 * Performs the interactive session. This handles data transmission between 671 * the client and the program. Note that the notion of stdin, stdout, and 672 * stderr in this function is sort of reversed: this function writes to stdin 673 * (of the child program), and reads from stdout and stderr (of the child 674 * program). 675 */ 676void server_loop(int pid, int fdin, int fdout, int fderr); 677 678/* Client side main loop for the interactive session. */ 679int client_loop(int have_pty, int escape_char); 680 681/* Linked list of custom environment strings (see auth-rsa.c). */ 682struct envstring { 683 struct envstring *next; 684 char *s; 685}; 686 687/* 688 * Ensure all of data on socket comes through. f==read || f==write 689 */ 690ssize_t atomicio(ssize_t (*f)(), int fd, void *s, size_t n); 691 692#ifdef KRB4 693#include <krb.h> 694/* 695 * Performs Kerberos v4 mutual authentication with the client. This returns 0 696 * if the client could not be authenticated, and 1 if authentication was 697 * successful. This may exit if there is a serious protocol violation. 698 */ 699int auth_krb4(const char *server_user, KTEXT auth, char **client); 700int krb4_init(uid_t uid); 701void krb4_cleanup_proc(void *ignore); 702int auth_krb4_password(struct passwd * pw, const char *password); 703 704#ifdef AFS 705#include <kafs.h> 706 707/* Accept passed Kerberos v4 ticket-granting ticket and AFS tokens. */ 708int auth_kerberos_tgt(struct passwd * pw, const char *string); 709int auth_afs_token(struct passwd * pw, const char *token_string); 710 711int creds_to_radix(CREDENTIALS * creds, unsigned char *buf); 712int radix_to_creds(const char *buf, CREDENTIALS * creds); 713#endif /* AFS */ 714 715#endif /* KRB4 */ 716 717#ifdef SKEY 718#include <skey.h> 719char *skey_fake_keyinfo(char *username); 720int auth_skey_password(struct passwd * pw, const char *password); 721#endif /* SKEY */ 722 723/* AF_UNSPEC or AF_INET or AF_INET6 */ 724extern int IPv4or6; 725 726#endif /* SSH_H */ 727