X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/6fa724bc01e9dd20a7f7e1b78ddc9a3ba7b42006..HEAD:/ssh.h diff --git a/ssh.h b/ssh.h index 653dfc2b..186cfff9 100644 --- a/ssh.h +++ b/ssh.h @@ -1,34 +1,16 @@ -/* - -ssh.h - -Author: Tatu Ylonen - -Copyright (c) 1995 Tatu Ylonen , Espoo, Finland - All rights reserved - -Created: Fri Mar 17 17:09:37 1995 ylo - -Generic header file for ssh. - -*/ - -/* RCSID("$Id$"); */ +/* $OpenBSD: ssh.h,v 1.78 2006/08/03 03:34:42 deraadt Exp $ */ -#ifndef SSH_H -#define SSH_H - -#include /* For struct sockaddr_in */ -#include /* For struct pw */ -#include /* For va_list */ - -#include "rsa.h" -#include "cipher.h" - -/* The default cipher used if IDEA is not supported by the remote host. - It is recommended that this be one of the mandatory ciphers (DES, 3DES), - though that is not required. */ -#define SSH_FALLBACK_CIPHER SSH_CIPHER_3DES +/* + * Author: Tatu Ylonen + * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland + * All rights reserved + * + * As far as I am concerned, the code I have written for this software + * can be used freely for any purpose. Any derived versions of this + * software must be clearly marked as such, and if the derived work is + * incompatible with the protocol description in the RFC file, it must be + * called by a name other than "ssh" or "Secure Shell". + */ /* Cipher used for encrypting authentication files. */ #define SSH_AUTHFILE_CIPHER SSH_CIPHER_3DES @@ -39,558 +21,82 @@ Generic header file for ssh. /* Maximum number of TCP/IP ports forwarded per direction. */ #define SSH_MAX_FORWARDS_PER_DIRECTION 100 -/* Maximum number of RSA authentication identity files that can be specified - in configuration files or on the command line. */ +/* + * Maximum number of RSA authentication identity files that can be specified + * in configuration files or on the command line. + */ #define SSH_MAX_IDENTITY_FILES 100 -/* Major protocol version. Different version indicates major incompatiblity - that prevents communication. */ -#define PROTOCOL_MAJOR 1 +/* + * Maximum length of lines in authorized_keys file. + * Current value permits 16kbit RSA and RSA1 keys and 8kbit DSA keys, with + * some room for options and comments. + */ +#define SSH_MAX_PUBKEY_BYTES 8192 -/* Minor protocol version. Different version indicates minor incompatibility - that does not prevent interoperation. */ -#define PROTOCOL_MINOR 5 +/* + * Major protocol version. Different version indicates major incompatibility + * that prevents communication. + * + * Minor protocol version. Different version indicates minor incompatibility + * that does not prevent interoperation. + */ +#define PROTOCOL_MAJOR_1 1 +#define PROTOCOL_MINOR_1 5 + +/* We support both SSH1 and SSH2 */ +#define PROTOCOL_MAJOR_2 2 +#define PROTOCOL_MINOR_2 0 -/* Name for the service. The port named by this service overrides the default - port if present. */ +/* + * Name for the service. The port named by this service overrides the + * default port if present. + */ #define SSH_SERVICE_NAME "ssh" -#ifndef ETCDIR -#define ETCDIR "/etc" -#endif /* ETCDIR */ - -#define PIDDIR "/var/run" - -/* System-wide file containing host keys of known hosts. This file should be - world-readable. */ -#define SSH_SYSTEM_HOSTFILE ETCDIR "/ssh_known_hosts" - -/* HOST_KEY_FILE /etc/ssh_host_key, - SERVER_CONFIG_FILE /etc/sshd_config, -and HOST_CONFIG_FILE /etc/ssh_config -are all defined in Makefile.in. Of these, ssh_host_key should be readable -only by root, whereas ssh_config should be world-readable. */ - -#define HOST_KEY_FILE ETCDIR "/ssh_host_key" -#define SERVER_CONFIG_FILE ETCDIR "/sshd_config" -#define HOST_CONFIG_FILE ETCDIR "/ssh_config" - -#ifndef SSH_PROGRAM -#define SSH_PROGRAM "/usr/bin/ssh" -#endif /* SSH_PROGRAM */ - -#ifndef LOGIN_PROGRAM -#define LOGIN_PROGRAM "/usr/bin/login" -#endif /* LOGIN_PROGRAM */ - -#ifndef ASKPASS_PROGRAM -#define ASKPASS_PROGRAM "/usr/lib/ssh/ssh-askpass" -#endif /* ASKPASS_PROGRAM */ - -/* The process id of the daemon listening for connections is saved - here to make it easier to kill the correct daemon when necessary. */ -#define SSH_DAEMON_PID_FILE PIDDIR "/sshd.pid" - -/* The directory in user\'s home directory in which the files reside. - The directory should be world-readable (though not all files are). */ -#define SSH_USER_DIR ".ssh" - -/* Per-user file containing host keys of known hosts. This file need - not be readable by anyone except the user him/herself, though this does - not contain anything particularly secret. */ -#define SSH_USER_HOSTFILE "~/.ssh/known_hosts" - -/* Name of the default file containing client-side authentication key. - This file should only be readable by the user him/herself. */ -#define SSH_CLIENT_IDENTITY ".ssh/identity" - -/* Configuration file in user\'s home directory. This file need not be - readable by anyone but the user him/herself, but does not contain - anything particularly secret. If the user\'s home directory resides - on an NFS volume where root is mapped to nobody, this may need to be - world-readable. */ -#define SSH_USER_CONFFILE ".ssh/config" - -/* File containing a list of those rsa keys that permit logging in as - this user. This file need not be - readable by anyone but the user him/herself, but does not contain - anything particularly secret. If the user\'s home directory resides - on an NFS volume where root is mapped to nobody, this may need to be - world-readable. (This file is read by the daemon which is running as - root.) */ -#define SSH_USER_PERMITTED_KEYS ".ssh/authorized_keys" - -/* Per-user and system-wide ssh "rc" files. These files are executed with - /bin/sh before starting the shell or command if they exist. They - will be passed "proto cookie" as arguments if X11 forwarding with - spoofing is in use. xauth will be run if neither of these exists. */ -#define SSH_USER_RC ".ssh/rc" -#define SSH_SYSTEM_RC ETCDIR "/sshrc" - -/* Ssh-only version of /etc/hosts.equiv. */ -#define SSH_HOSTS_EQUIV ETCDIR "/shosts.equiv" - -/* Additionally, the daemon may use ~/.rhosts and /etc/hosts.equiv if - rhosts authentication is enabled. */ +/* + * Name of the environment variable containing the process ID of the + * authentication agent. + */ +#define SSH_AGENTPID_ENV_NAME "SSH_AGENT_PID" -/* Name of the environment variable containing the pathname of the - authentication socket. */ -#define SSH_AUTHSOCKET_ENV_NAME "SSH_AUTH_SOCK" +/* + * Name of the environment variable containing the pathname of the + * authentication socket. + */ +#define SSH_AUTHSOCKET_ENV_NAME "SSH_AUTH_SOCK" -/* Name of the environment variable containing the pathname of the - authentication socket. */ -#define SSH_AGENTPID_ENV_NAME "SSH_AGENT_PID" +/* + * Environment variable for overwriting the default location of askpass + */ +#define SSH_ASKPASS_ENV "SSH_ASKPASS" -/* Force host key length and server key length to differ by at least this - many bits. This is to make double encryption with rsaref work. */ +/* + * Force host key length and server key length to differ by at least this + * many bits. This is to make double encryption with rsaref work. + */ #define SSH_KEY_BITS_RESERVED 128 -/* Length of the session key in bytes. (Specified as 256 bits in the - protocol.) */ +/* + * Length of the session key in bytes. (Specified as 256 bits in the + * protocol.) + */ #define SSH_SESSION_KEY_LENGTH 32 -/* Name of Kerberos service for SSH to use. */ -#define KRB4_SERVICE_NAME "rcmd" - -/* Authentication methods. New types can be added, but old types should not - be removed for compatibility. The maximum allowed value is 31. */ -#define SSH_AUTH_RHOSTS 1 -#define SSH_AUTH_RSA 2 -#define SSH_AUTH_PASSWORD 3 -#define SSH_AUTH_RHOSTS_RSA 4 - /* 5 is TIS */ -#define SSH_AUTH_KERBEROS 6 -#define SSH_PASS_KERBEROS_TGT 7 - /* 8 to 15 are reserved */ -#define SSH_PASS_AFS_TOKEN 21 - -/* Protocol flags. These are bit masks. */ -#define SSH_PROTOFLAG_SCREEN_NUMBER 1 /* X11 forwarding includes screen */ -#define SSH_PROTOFLAG_HOST_IN_FWD_OPEN 2 /* forwarding opens contain host */ - -/* Definition of message types. New values can be added, but old values - should not be removed or without careful consideration of the consequences - for compatibility. The maximum value is 254; value 255 is reserved - for future extension. */ -/* Message name */ /* msg code */ /* arguments */ -#define SSH_MSG_NONE 0 /* no message */ -#define SSH_MSG_DISCONNECT 1 /* cause (string) */ -#define SSH_SMSG_PUBLIC_KEY 2 /* ck,msk,srvk,hostk */ -#define SSH_CMSG_SESSION_KEY 3 /* key (BIGNUM) */ -#define SSH_CMSG_USER 4 /* user (string) */ -#define SSH_CMSG_AUTH_RHOSTS 5 /* user (string) */ -#define SSH_CMSG_AUTH_RSA 6 /* modulus (BIGNUM) */ -#define SSH_SMSG_AUTH_RSA_CHALLENGE 7 /* int (BIGNUM) */ -#define SSH_CMSG_AUTH_RSA_RESPONSE 8 /* int (BIGNUM) */ -#define SSH_CMSG_AUTH_PASSWORD 9 /* pass (string) */ -#define SSH_CMSG_REQUEST_PTY 10 /* TERM, tty modes */ -#define SSH_CMSG_WINDOW_SIZE 11 /* row,col,xpix,ypix */ -#define SSH_CMSG_EXEC_SHELL 12 /* */ -#define SSH_CMSG_EXEC_CMD 13 /* cmd (string) */ -#define SSH_SMSG_SUCCESS 14 /* */ -#define SSH_SMSG_FAILURE 15 /* */ -#define SSH_CMSG_STDIN_DATA 16 /* data (string) */ -#define SSH_SMSG_STDOUT_DATA 17 /* data (string) */ -#define SSH_SMSG_STDERR_DATA 18 /* data (string) */ -#define SSH_CMSG_EOF 19 /* */ -#define SSH_SMSG_EXITSTATUS 20 /* status (int) */ -#define SSH_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* channel (int) */ -#define SSH_MSG_CHANNEL_OPEN_FAILURE 22 /* channel (int) */ -#define SSH_MSG_CHANNEL_DATA 23 /* ch,data (int,str) */ -#define SSH_MSG_CHANNEL_CLOSE 24 /* channel (int) */ -#define SSH_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* channel (int) */ -/* SSH_CMSG_X11_REQUEST_FORWARDING 26 OBSOLETE */ -#define SSH_SMSG_X11_OPEN 27 /* channel (int) */ -#define SSH_CMSG_PORT_FORWARD_REQUEST 28 /* p,host,hp (i,s,i) */ -#define SSH_MSG_PORT_OPEN 29 /* ch,h,p (i,s,i) */ -#define SSH_CMSG_AGENT_REQUEST_FORWARDING 30 /* */ -#define SSH_SMSG_AGENT_OPEN 31 /* port (int) */ -#define SSH_MSG_IGNORE 32 /* string */ -#define SSH_CMSG_EXIT_CONFIRMATION 33 /* */ -#define SSH_CMSG_X11_REQUEST_FORWARDING 34 /* proto,data (s,s) */ -#define SSH_CMSG_AUTH_RHOSTS_RSA 35 /* user,mod (s,mpi) */ -#define SSH_MSG_DEBUG 36 /* string */ -#define SSH_CMSG_REQUEST_COMPRESSION 37 /* level 1-9 (int) */ -#define SSH_CMSG_MAX_PACKET_SIZE 38 /* size 4k-1024k (int) */ -#define SSH_CMSG_AUTH_TIS 39 /* this is proto-1.5, but we ignore TIS */ -#define SSH_SMSG_AUTH_TIS_CHALLENGE 40 -#define SSH_CMSG_AUTH_TIS_RESPONSE 41 - -#define SSH_CMSG_AUTH_KERBEROS 42 /* (KTEXT) */ -#define SSH_SMSG_AUTH_KERBEROS_RESPONSE 43 /* (KTEXT) */ -#define SSH_CMSG_HAVE_KERBEROS_TGT 44 /* credentials (s) */ -#define SSH_CMSG_HAVE_AFS_TOKEN 65 /* token (s) */ - -/*------------ definitions for login.c -------------*/ - -/* Returns the time when the user last logged in. Returns 0 if the - information is not available. This must be called before record_login. - The host from which the user logged in is stored in buf. */ -unsigned long get_last_login_time(uid_t uid, const char *logname, - char *buf, unsigned int bufsize); - -/* Records that the user has logged in. This does many things normally - done by login(1). */ -void record_login(int pid, const char *ttyname, const char *user, uid_t uid, - const char *host, struct sockaddr_in *addr); - -/* Records that the user has logged out. This does many thigs normally - done by login(1) or init. */ -void record_logout(int pid, const char *ttyname); - -/*------------ definitions for sshconnect.c ----------*/ - -/* Opens a TCP/IP connection to the remote server on the given host. If - port is 0, the default port will be used. If anonymous is zero, - a privileged port will be allocated to make the connection. - This requires super-user privileges if anonymous is false. - Connection_attempts specifies the maximum number of tries, one per - second. This returns true on success, and zero on failure. If the - connection is successful, this calls packet_set_connection for the - connection. */ -int ssh_connect(const char *host, struct sockaddr_in *hostaddr, - int port, int connection_attempts, - int anonymous, uid_t original_real_uid, - const char *proxy_command); - -/* Starts a dialog with the server, and authenticates the current user on the - server. This does not need any extra privileges. The basic connection - to the server must already have been established before this is called. - If login fails, this function prints an error and never returns. - This initializes the random state, and leaves it initialized (it will also - have references from the packet module). */ - -void ssh_login(int host_key_valid, RSA *host_key, const char *host, - struct sockaddr_in *hostaddr, uid_t original_real_uid); - -/*------------ Definitions for various authentication methods. -------*/ - -/* Tries to authenticate the user using the .rhosts file. Returns true if - authentication succeeds. If ignore_rhosts is non-zero, this will not - consider .rhosts and .shosts (/etc/hosts.equiv will still be used). */ -int auth_rhosts(struct passwd *pw, const char *client_user); - -/* Tries to authenticate the user using the .rhosts file and the host using - its host key. Returns true if authentication succeeds. */ -int auth_rhosts_rsa(struct passwd *pw, const char *client_user, - unsigned int bits, BIGNUM *client_host_key_e, - BIGNUM *client_host_key_n); - -/* Tries to authenticate the user using password. Returns true if - authentication succeeds. */ -int auth_password(struct passwd *pw, const char *password); - -/* Performs the RSA authentication dialog with the client. This returns - 0 if the client could not be authenticated, and 1 if authentication was - successful. This may exit if there is a serious protocol violation. */ -int auth_rsa(struct passwd *pw, BIGNUM *client_n); - -/* Parses an RSA key (number of bits, e, n) from a string. Moves the pointer - over the key. Skips any whitespace at the beginning and at end. */ -int auth_rsa_read_key(char **cpp, unsigned int *bitsp, BIGNUM *e, BIGNUM *n); - -/* Returns the name of the machine at the other end of the socket. The - returned string should be freed by the caller. */ -char *get_remote_hostname(int socket); - -/* Return the canonical name of the host in the other side of the current - connection (as returned by packet_get_connection). The host name is - cached, so it is efficient to call this several times. */ -const char *get_canonical_hostname(void); - -/* Returns the remote IP address as an ascii string. The value need not be - freed by the caller. */ -const char *get_remote_ipaddr(void); - -/* Returns the port number of the peer of the socket. */ -int get_peer_port(int sock); - -/* Returns the port number of the remote host. */ -int get_remote_port(void); +/* Used to identify ``EscapeChar none'' */ +#define SSH_ESCAPECHAR_NONE -2 -/* Tries to match the host name (which must be in all lowercase) against the - comma-separated sequence of subpatterns (each possibly preceded by ! to - indicate negation). Returns true if there is a positive match; zero - otherwise. */ -int match_hostname(const char *host, const char *pattern, unsigned int len); - -/* Checks whether the given host is already in the list of our known hosts. - Returns HOST_OK if the host is known and has the specified key, - HOST_NEW if the host is not known, and HOST_CHANGED if the host is known - but used to have a different host key. The host must be in all lowercase. */ -typedef enum { HOST_OK, HOST_NEW, HOST_CHANGED } HostStatus; -HostStatus check_host_in_hostfile(const char *filename, - const char *host, unsigned int bits, - BIGNUM *e, BIGNUM *n, - BIGNUM *ke, BIGNUM *kn); - -/* Appends an entry to the host file. Returns false if the entry - could not be appended. */ -int add_host_to_hostfile(const char *filename, const char *host, - unsigned int bits, BIGNUM *e, BIGNUM *n); - -/* Performs the RSA authentication challenge-response dialog with the client, - and returns true (non-zero) if the client gave the correct answer to - our challenge; returns zero if the client gives a wrong answer. */ -int auth_rsa_challenge_dialog(unsigned int bits, BIGNUM *e, BIGNUM *n); - -/* Reads a passphrase from /dev/tty with echo turned off. Returns the - passphrase (allocated with xmalloc). Exits if EOF is encountered. - If from_stdin is true, the passphrase will be read from stdin instead. */ -char *read_passphrase(const char *prompt, int from_stdin); - -/* Saves the authentication (private) key in a file, encrypting it with - passphrase. The identification of the file (lowest 64 bits of n) - will precede the key to provide identification of the key without - needing a passphrase. */ -int save_private_key(const char *filename, const char *passphrase, - RSA *private_key, const char *comment); - -/* Loads the public part of the key file (public key and comment). - Returns 0 if an error occurred; zero if the public key was successfully - read. The comment of the key is returned in comment_return if it is - non-NULL; the caller must free the value with xfree. */ -int load_public_key(const char *filename, RSA *pub, - char **comment_return); - -/* Loads the private key from the file. Returns 0 if an error is encountered - (file does not exist or is not readable, or passphrase is bad). - This initializes the private key. The comment of the key is returned - in comment_return if it is non-NULL; the caller must free the value - with xfree. */ -int load_private_key(const char *filename, const char *passphrase, - RSA *private_key, char **comment_return); - -/*------------ Definitions for logging. -----------------------*/ - -/* Supported syslog facilities and levels. */ -typedef enum -{ - SYSLOG_FACILITY_DAEMON, - SYSLOG_FACILITY_USER, - SYSLOG_FACILITY_AUTH, - SYSLOG_FACILITY_LOCAL0, - SYSLOG_FACILITY_LOCAL1, - SYSLOG_FACILITY_LOCAL2, - SYSLOG_FACILITY_LOCAL3, - SYSLOG_FACILITY_LOCAL4, - SYSLOG_FACILITY_LOCAL5, - SYSLOG_FACILITY_LOCAL6, - SYSLOG_FACILITY_LOCAL7 -} SyslogFacility; - -typedef enum -{ - SYSLOG_LEVEL_QUIET, - SYSLOG_LEVEL_FATAL, - SYSLOG_LEVEL_ERROR, - SYSLOG_LEVEL_INFO, - SYSLOG_LEVEL_CHAT, - SYSLOG_LEVEL_DEBUG -} LogLevel; - -/* Initializes logging. */ -void log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr); - -/* Logging implementation, depending on server or client */ -void do_log(LogLevel level, const char *fmt, va_list args); - -/* Output a message to syslog or stderr */ -void fatal(const char *fmt, ...); -void error(const char *fmt, ...); -void log(const char *fmt, ...); -void chat(const char *fmt, ...); -void debug(const char *fmt, ...); - -/* same as fatal() but w/o logging */ -void fatal_cleanup(void); - -/* Registers a cleanup function to be called by fatal()/fatal_cleanup() before exiting. - It is permissible to call fatal_remove_cleanup for the function itself - from the function. */ -void fatal_add_cleanup(void (*proc)(void *context), void *context); - -/* Removes a cleanup function to be called at fatal(). */ -void fatal_remove_cleanup(void (*proc)(void *context), void *context); - -/*---------------- definitions for channels ------------------*/ - -/* Sets specific protocol options. */ -void channel_set_options(int hostname_in_open); - -/* Allocate a new channel object and set its type and socket. Remote_name - must have been allocated with xmalloc; this will free it when the channel - is freed. */ -int channel_allocate(int type, int sock, char *remote_name); - -/* Free the channel and close its socket. */ -void channel_free(int channel); - -/* Add any bits relevant to channels in select bitmasks. */ -void channel_prepare_select(fd_set *readset, fd_set *writeset); - -/* After select, perform any appropriate operations for channels which - have events pending. */ -void channel_after_select(fd_set *readset, fd_set *writeset); - -/* If there is data to send to the connection, send some of it now. */ -void channel_output_poll(void); - -/* This is called when a packet of type CHANNEL_DATA has just been received. - The message type has already been consumed, but channel number and data - is still there. */ -void channel_input_data(int payload_len); - -/* Returns true if no channel has too much buffered data. */ -int channel_not_very_much_buffered_data(void); - -/* This is called after receiving CHANNEL_CLOSE. */ -void channel_input_close(void); - -/* This is called after receiving CHANNEL_CLOSE_CONFIRMATION. */ -void channel_input_close_confirmation(void); - -/* This is called after receiving CHANNEL_OPEN_CONFIRMATION. */ -void channel_input_open_confirmation(void); - -/* This is called after receiving CHANNEL_OPEN_FAILURE from the other side. */ -void channel_input_open_failure(void); - -/* This closes any sockets that are listening for connections; this removes - any unix domain sockets. */ -void channel_stop_listening(void); - -/* Closes the sockets of all channels. This is used to close extra file - descriptors after a fork. */ -void channel_close_all(void); - -/* Returns the maximum file descriptor number used by the channels. */ -int channel_max_fd(void); - -/* Returns true if there is still an open channel over the connection. */ -int channel_still_open(void); - -/* Returns a string containing a list of all open channels. The list is - suitable for displaying to the user. It uses crlf instead of newlines. - The caller should free the string with xfree. */ -char *channel_open_message(void); - -/* Initiate forwarding of connections to local port "port" through the secure - channel to host:port from remote side. This never returns if there - was an error. */ -void channel_request_local_forwarding(int port, const char *host, - int remote_port); - -/* Initiate forwarding of connections to port "port" on remote host through - the secure channel to host:port from local side. This never returns - if there was an error. This registers that open requests for that - port are permitted. */ -void channel_request_remote_forwarding(int port, const char *host, - int remote_port); - -/* Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually - called by the server, because the user could connect to any port anyway, - and the server has no way to know but to trust the client anyway. */ -void channel_permit_all_opens(void); - -/* This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates - listening for the port, and sends back a success reply (or disconnect - message if there was an error). This never returns if there was an - error. */ -void channel_input_port_forward_request(int is_root); - -/* This is called after receiving PORT_OPEN message. This attempts to connect - to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION or - CHANNEL_OPEN_FAILURE. */ -void channel_input_port_open(int payload_len); - -/* Creates a port for X11 connections, and starts listening for it. - Returns the display name, or NULL if an error was encountered. */ -char *x11_create_display(int screen); - -/* Creates an internet domain socket for listening for X11 connections. - Returns a suitable value for the DISPLAY variable, or NULL if an error - occurs. */ -char *x11_create_display_inet(int screen); - -/* This is called when SSH_SMSG_X11_OPEN is received. The packet contains - the remote channel number. We should do whatever we want, and respond - with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. */ -void x11_input_open(int payload_len); - -/* Requests forwarding of X11 connections. This should be called on the - client only. */ -void x11_request_forwarding(void); - -/* Requests forwarding for X11 connections, with authentication spoofing. - This should be called in the client only. */ -void x11_request_forwarding_with_spoofing(const char *proto, const char *data); - -/* Sends a message to the server to request authentication fd forwarding. */ -void auth_request_forwarding(void); - -/* Returns the name of the forwarded authentication socket. Returns NULL - if there is no forwarded authentication socket. The returned value points - to a static buffer. */ -char *auth_get_socket_name(void); - -/* This if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. - This starts forwarding authentication requests. */ -void auth_input_request_forwarding(struct passwd *pw); - -/* This is called to process an SSH_SMSG_AGENT_OPEN message. */ -void auth_input_open_request(void); - -/* Returns true if the given string matches the pattern (which may contain - ? and * as wildcards), and zero if it does not match. */ -int match_pattern(const char *s, const char *pattern); - -/* Expands tildes in the file name. Returns data allocated by xmalloc. - Warning: this calls getpw*. */ -char *tilde_expand_filename(const char *filename, uid_t my_uid); - -/* Performs the interactive session. This handles data transmission between - the client and the program. Note that the notion of stdin, stdout, and - stderr in this function is sort of reversed: this function writes to - stdin (of the child program), and reads from stdout and stderr (of the - child program). */ -void server_loop(int pid, int fdin, int fdout, int fderr); - -/* Client side main loop for the interactive session. */ -int client_loop(int have_pty, int escape_char); - -/* Linked list of custom environment strings (see auth-rsa.c). */ -struct envstring { - struct envstring *next; - char *s; -}; - -#ifdef KRB4 -#include - -/* Performs Kerberos v4 mutual authentication with the client. This returns - 0 if the client could not be authenticated, and 1 if authentication was - successful. This may exit if there is a serious protocol violation. */ -int auth_krb4(const char *server_user, KTEXT auth, char **client); -int krb4_init(uid_t uid); -void krb4_cleanup_proc(void *ignore); - -#ifdef AFS -#include - -/* Accept passed Kerberos v4 ticket-granting ticket and AFS tokens. */ -int auth_kerberos_tgt(struct passwd *pw, const char *string); -int auth_afs_token(struct passwd *pw, const char *token_string); - -int creds_to_radix(CREDENTIALS *creds, unsigned char *buf); -int radix_to_creds(const char *buf, CREDENTIALS *creds); -#endif /* AFS */ - -#endif /* KRB4 */ - -#ifdef SKEY -#include -char *skey_fake_keyinfo(char *username); -#endif /* SKEY */ - -#endif /* SSH_H */ +/* + * unprivileged user when UsePrivilegeSeparation=yes; + * sshd will change its privileges to this user and its + * primary group. + */ +#ifndef SSH_PRIVSEP_USER +#define SSH_PRIVSEP_USER "sshd" +#endif + +/* Minimum modulus size (n) for RSA keys. */ +#define SSH_RSA_MINIMUM_MODULUS_SIZE 768 + +/* Listen backlog for sshd, ssh-agent and forwarding sockets */ +#define SSH_LISTEN_BACKLOG 128