| /* |
| * |
| * ssh.h |
| * |
| * Author: Tatu Ylonen <ylo@cs.hut.fi> |
| * |
| * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| * All rights reserved |
| * |
| * Created: Fri Mar 17 17:09:37 1995 ylo |
| * |
| * Generic header file for ssh. |
| * |
| */ |
| |
| /* RCSID("$Id: ssh.h,v 1.35 2000/04/29 13:57:12 damien Exp $"); */ |
| |
| #ifndef SSH_H |
| #define SSH_H |
| |
| #include <netinet/in.h> /* For struct sockaddr_in */ |
| #include <pwd.h> /* For struct pw */ |
| #include <stdarg.h> /* For va_list */ |
| #include <sys/socket.h> /* For struct sockaddr_storage */ |
| #include "fake-socket.h" /* For struct sockaddr_storage */ |
| #ifdef HAVE_SYS_SELECT_H |
| # include <sys/select.h> |
| #endif |
| #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 |
| |
| /* Cipher used for encrypting authentication files. */ |
| #define SSH_AUTHFILE_CIPHER SSH_CIPHER_3DES |
| |
| /* Default port number. */ |
| #define SSH_DEFAULT_PORT 22 |
| |
| /* 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. |
| */ |
| #define SSH_MAX_IDENTITY_FILES 100 |
| |
| /* |
| * Major protocol version. Different version indicates major incompatiblity |
| * 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. |
| */ |
| #define SSH_SERVICE_NAME "ssh" |
| |
| #if defined(USE_PAM) && !defined(SSHD_PAM_SERVICE) |
| # define SSHD_PAM_SERVICE "sshd" |
| #endif |
| |
| #ifndef ETCDIR |
| #define ETCDIR "/etc" |
| #endif /* ETCDIR */ |
| |
| #ifndef PIDDIR |
| #define PIDDIR "/var/run" |
| #endif /* PIDDIR */ |
| |
| /* |
| * System-wide file containing host keys of known hosts. This file should be |
| * world-readable. |
| */ |
| #define SSH_SYSTEM_HOSTFILE ETCDIR "/ssh_known_hosts" |
| #define SSH_SYSTEM_HOSTFILE2 ETCDIR "/ssh_known_hosts2" |
| |
| /* |
| * Of these, ssh_host_key must 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" |
| #define DSA_KEY_FILE ETCDIR "/ssh_host_dsa_key" |
| |
| #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" |
| #define SSH_USER_HOSTFILE2 "~/.ssh/known_hosts2" |
| |
| /* |
| * 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" |
| #define SSH_USER_PERMITTED_KEYS2 ".ssh/authorized_keys2" |
| |
| /* |
| * 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. Additionally, the daemon may use |
| * ~/.rhosts and /etc/hosts.equiv if rhosts authentication is enabled. |
| */ |
| #define SSH_HOSTS_EQUIV ETCDIR "/shosts.equiv" |
| |
| /* |
| * 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" |
| |
| /* |
| * Default path to ssh-askpass used by ssh-add, |
| * environment variable for overwriting the default location |
| */ |
| #ifndef SSH_ASKPASS_DEFAULT |
| # define SSH_ASKPASS_DEFAULT "/usr/X11R6/bin/ssh-askpass" |
| #endif |
| #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. |
| */ |
| #define SSH_KEY_BITS_RESERVED 128 |
| |
| /* |
| * 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 |
| #define SSH_AUTH_TIS 5 |
| #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 /* we use this for s/key */ |
| #define SSH_SMSG_AUTH_TIS_CHALLENGE 40 /* challenge (string) */ |
| #define SSH_CMSG_AUTH_TIS_RESPONSE 41 /* response (string) */ |
| #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(pid_t pid, const char *ttyname, const char *user, uid_t uid, |
| const char *host, struct sockaddr *addr); |
| |
| /* |
| * Records that the user has logged out. This does many thigs normally done |
| * by login(1) or init. |
| */ |
| void record_logout(pid_t 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_storage * hostaddr, |
| u_short 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 * 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, RSA* client_host_key); |
| |
| /* |
| * 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/local host. */ |
| int get_remote_port(void); |
| int get_local_port(void); |
| |
| |
| /* |
| * 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(RSA *pk); |
| |
| /* |
| * 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); |
| |
| |
| /*------------ 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_VERBOSE, |
| 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); |
| |
| /* name to facility/level */ |
| SyslogFacility log_facility_number(char *name); |
| LogLevel log_level_number(char *name); |
| |
| /* Output a message to syslog or stderr */ |
| void fatal(const char *fmt,...) __attribute__((format(printf, 1, 2))); |
| void error(const char *fmt,...) __attribute__((format(printf, 1, 2))); |
| void log(const char *fmt,...) __attribute__((format(printf, 1, 2))); |
| void verbose(const char *fmt,...) __attribute__((format(printf, 1, 2))); |
| void debug(const char *fmt,...) __attribute__((format(printf, 1, 2))); |
| |
| /* 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); |
| |
| /* ---- misc */ |
| |
| /* |
| * 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(pid_t pid, int fdin, int fdout, int fderr); |
| void server_loop2(void); |
| |
| /* 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; |
| }; |
| |
| /* |
| * Ensure all of data on socket comes through. f==read || f==write |
| */ |
| ssize_t atomicio(ssize_t (*f)(), int fd, void *s, size_t n); |
| |
| #ifdef KRB4 |
| #include <krb.h> |
| /* |
| * 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); |
| int auth_krb4_password(struct passwd * pw, const char *password); |
| |
| #ifdef AFS |
| #include <kafs.h> |
| |
| /* 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 <skey.h> |
| char *skey_fake_keyinfo(char *username); |
| int auth_skey_password(struct passwd * pw, const char *password); |
| #endif /* SKEY */ |
| |
| /* AF_UNSPEC or AF_INET or AF_INET6 */ |
| extern int IPv4or6; |
| |
| #ifdef USE_PAM |
| #include "auth-pam.h" |
| #endif /* USE_PAM */ |
| |
| #endif /* SSH_H */ |