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Diffstat (limited to 'crypto/openssh/packet.h')
| -rw-r--r-- | crypto/openssh/packet.h | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/crypto/openssh/packet.h b/crypto/openssh/packet.h new file mode 100644 index 0000000..ea0a839 --- /dev/null +++ b/crypto/openssh/packet.h @@ -0,0 +1,218 @@ +/* + * Author: Tatu Ylonen <ylo@cs.hut.fi> + * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland + * All rights reserved + * Interface for the packet protocol functions. + * + * 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". + */ + +/* RCSID("$OpenBSD: packet.h,v 1.17 2000/09/07 20:27:52 deraadt Exp $"); */ +/* $FreeBSD$ */ + +#ifndef PACKET_H +#define PACKET_H + +#include <openssl/bn.h> + +/* + * Sets the socket used for communication. Disables encryption until + * packet_set_encryption_key is called. It is permissible that fd_in and + * fd_out are the same descriptor; in that case it is assumed to be a socket. + */ +void packet_set_connection(int fd_in, int fd_out); + +/* Puts the connection file descriptors into non-blocking mode. */ +void packet_set_nonblocking(void); + +/* Returns the file descriptor used for input. */ +int packet_get_connection_in(void); + +/* Returns the file descriptor used for output. */ +int packet_get_connection_out(void); + +/* + * Closes the connection (both descriptors) and clears and frees internal + * data structures. + */ +void packet_close(void); + +/* + * Causes any further packets to be encrypted using the given key. The same + * key is used for both sending and reception. However, both directions are + * encrypted independently of each other. Cipher types are defined in ssh.h. + */ +void +packet_set_encryption_key(const unsigned char *key, unsigned int keylen, + int cipher_type); + +/* + * Sets remote side protocol flags for the current connection. This can be + * called at any time. + */ +void packet_set_protocol_flags(unsigned int flags); + +/* Returns the remote protocol flags set earlier by the above function. */ +unsigned int packet_get_protocol_flags(void); + +/* Enables compression in both directions starting from the next packet. */ +void packet_start_compression(int level); + +/* + * Informs that the current session is interactive. Sets IP flags for + * optimal performance in interactive use. + */ +void packet_set_interactive(int interactive, int keepalives); + +/* Returns true if the current connection is interactive. */ +int packet_is_interactive(void); + +/* Starts constructing a packet to send. */ +void packet_start(int type); + +/* Appends a character to the packet data. */ +void packet_put_char(int ch); + +/* Appends an integer to the packet data. */ +void packet_put_int(unsigned int value); + +/* Appends an arbitrary precision integer to packet data. */ +void packet_put_bignum(BIGNUM * value); +void packet_put_bignum2(BIGNUM * value); + +/* Appends a string to packet data. */ +void packet_put_string(const char *buf, unsigned int len); +void packet_put_cstring(const char *str); +void packet_put_raw(const char *buf, unsigned int len); + +/* + * Finalizes and sends the packet. If the encryption key has been set, + * encrypts the packet before sending. + */ +void packet_send(void); + +/* Waits until a packet has been received, and returns its type. */ +int packet_read(int *payload_len_ptr); + +/* + * Waits until a packet has been received, verifies that its type matches + * that given, and gives a fatal error and exits if there is a mismatch. + */ +void packet_read_expect(int *payload_len_ptr, int type); + +/* + * Checks if a full packet is available in the data received so far via + * packet_process_incoming. If so, reads the packet; otherwise returns + * SSH_MSG_NONE. This does not wait for data from the connection. + * SSH_MSG_DISCONNECT is handled specially here. Also, SSH_MSG_IGNORE + * messages are skipped by this function and are never returned to higher + * levels. + */ +int packet_read_poll(int *packet_len_ptr); + +/* + * Buffers the given amount of input characters. This is intended to be used + * together with packet_read_poll. + */ +void packet_process_incoming(const char *buf, unsigned int len); + +/* Returns a character (0-255) from the packet data. */ +unsigned int packet_get_char(void); + +/* Returns an integer from the packet data. */ +unsigned int packet_get_int(void); + +/* + * Returns an arbitrary precision integer from the packet data. The integer + * must have been initialized before this call. + */ +void packet_get_bignum(BIGNUM * value, int *length_ptr); +void packet_get_bignum2(BIGNUM * value, int *length_ptr); +char *packet_get_raw(int *length_ptr); + +/* + * Returns a string from the packet data. The string is allocated using + * xmalloc; it is the responsibility of the calling program to free it when + * no longer needed. The length_ptr argument may be NULL, or point to an + * integer into which the length of the string is stored. + */ +char *packet_get_string(unsigned int *length_ptr); + +/* + * Logs the error in syslog using LOG_INFO, constructs and sends a disconnect + * packet, closes the connection, and exits. This function never returns. + * The error message should not contain a newline. The total length of the + * message must not exceed 1024 bytes. + */ +void packet_disconnect(const char *fmt,...) __attribute__((format(printf, 1, 2))); + +/* + * Sends a diagnostic message to the other side. This message can be sent at + * any time (but not while constructing another message). The message is + * printed immediately, but only if the client is being executed in verbose + * mode. These messages are primarily intended to ease debugging + * authentication problems. The total length of the message must not exceed + * 1024 bytes. This will automatically call packet_write_wait. If the + * remote side protocol flags do not indicate that it supports SSH_MSG_DEBUG, + * this will do nothing. + */ +void packet_send_debug(const char *fmt,...) __attribute__((format(printf, 1, 2))); + +/* Checks if there is any buffered output, and tries to write some of the output. */ +void packet_write_poll(void); + +/* Waits until all pending output data has been written. */ +void packet_write_wait(void); + +/* Returns true if there is buffered data to write to the connection. */ +int packet_have_data_to_write(void); + +/* Returns true if there is not too much data to write to the connection. */ +int packet_not_very_much_data_to_write(void); + +/* maximum packet size, requested by client with SSH_CMSG_MAX_PACKET_SIZE */ +extern int max_packet_size; +int packet_set_maxsize(int s); +#define packet_get_maxsize() max_packet_size + +/* Stores tty modes from the fd into current packet. */ +void tty_make_modes(int fd); + +/* Parses tty modes for the fd from the current packet. */ +void tty_parse_modes(int fd, int *n_bytes_ptr); + +#define packet_integrity_check(payload_len, expected_len, type) \ +do { \ + int _p = (payload_len), _e = (expected_len); \ + if (_p != _e) { \ + log("Packet integrity error (%d != %d) at %s:%d", \ + _p, _e, __FILE__, __LINE__); \ + packet_disconnect("Packet integrity error. (%d)", (type)); \ + } \ +} while (0) + +#define packet_done() \ +do { \ + int _len = packet_remaining(); \ + if (_len > 0) { \ + log("Packet integrity error (%d bytes remaining) at %s:%d", \ + _len ,__FILE__, __LINE__); \ + packet_disconnect("Packet integrity error."); \ + } \ +} while (0) + +/* remote host is connected via a socket/ipv4 */ +int packet_connection_is_on_socket(void); +int packet_connection_is_ipv4(void); + +/* enable SSH2 packet format */ +void packet_set_ssh2_format(void); + +/* returns remaining payload bytes */ +int packet_remaining(void); + +#endif /* PACKET_H */ |
