Annotation of src/usr.bin/ssh/packet.h, Revision 1.22
1.1 deraadt 1: /*
1.5 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
5: * Interface for the packet protocol functions.
1.15 markus 6: *
1.17 deraadt 7: * As far as I am concerned, the code I have written for this software
8: * can be used freely for any purpose. Any derived versions of this
9: * software must be clearly marked as such, and if the derived work is
10: * incompatible with the protocol description in the RFC file, it must be
11: * called by a name other than "ssh" or "Secure Shell".
1.5 deraadt 12: */
1.1 deraadt 13:
1.22 ! stevesk 14: /* RCSID("$OpenBSD: packet.h,v 1.21 2001/02/28 21:27:47 markus Exp $"); */
1.1 deraadt 15:
16: #ifndef PACKET_H
17: #define PACKET_H
18:
1.13 markus 19: #include <openssl/bn.h>
1.1 deraadt 20:
1.6 markus 21: /*
22: * Sets the socket used for communication. Disables encryption until
23: * packet_set_encryption_key is called. It is permissible that fd_in and
24: * fd_out are the same descriptor; in that case it is assumed to be a socket.
25: */
1.5 deraadt 26: void packet_set_connection(int fd_in, int fd_out);
1.1 deraadt 27:
28: /* Puts the connection file descriptors into non-blocking mode. */
1.5 deraadt 29: void packet_set_nonblocking(void);
1.1 deraadt 30:
31: /* Returns the file descriptor used for input. */
1.5 deraadt 32: int packet_get_connection_in(void);
1.1 deraadt 33:
34: /* Returns the file descriptor used for output. */
1.5 deraadt 35: int packet_get_connection_out(void);
1.1 deraadt 36:
1.6 markus 37: /*
38: * Closes the connection (both descriptors) and clears and frees internal
39: * data structures.
40: */
1.5 deraadt 41: void packet_close(void);
1.1 deraadt 42:
1.6 markus 43: /*
44: * Causes any further packets to be encrypted using the given key. The same
45: * key is used for both sending and reception. However, both directions are
46: * encrypted independently of each other. Cipher types are defined in ssh.h.
47: */
1.15 markus 48: void
1.18 markus 49: packet_set_encryption_key(const u_char *key, u_int keylen,
1.5 deraadt 50: int cipher_type);
1.1 deraadt 51:
1.6 markus 52: /*
53: * Sets remote side protocol flags for the current connection. This can be
54: * called at any time.
55: */
1.18 markus 56: void packet_set_protocol_flags(u_int flags);
1.1 deraadt 57:
58: /* Returns the remote protocol flags set earlier by the above function. */
1.18 markus 59: u_int packet_get_protocol_flags(void);
1.1 deraadt 60:
61: /* Enables compression in both directions starting from the next packet. */
1.5 deraadt 62: void packet_start_compression(int level);
1.1 deraadt 63:
1.6 markus 64: /*
65: * Informs that the current session is interactive. Sets IP flags for
66: * optimal performance in interactive use.
67: */
1.19 markus 68: void packet_set_interactive(int interactive);
1.1 deraadt 69:
70: /* Returns true if the current connection is interactive. */
1.5 deraadt 71: int packet_is_interactive(void);
1.1 deraadt 72:
73: /* Starts constructing a packet to send. */
1.5 deraadt 74: void packet_start(int type);
1.1 deraadt 75:
76: /* Appends a character to the packet data. */
1.5 deraadt 77: void packet_put_char(int ch);
1.1 deraadt 78:
79: /* Appends an integer to the packet data. */
1.18 markus 80: void packet_put_int(u_int value);
1.1 deraadt 81:
82: /* Appends an arbitrary precision integer to packet data. */
1.5 deraadt 83: void packet_put_bignum(BIGNUM * value);
1.11 markus 84: void packet_put_bignum2(BIGNUM * value);
1.1 deraadt 85:
86: /* Appends a string to packet data. */
1.18 markus 87: void packet_put_string(const char *buf, u_int len);
1.11 markus 88: void packet_put_cstring(const char *str);
1.18 markus 89: void packet_put_raw(const char *buf, u_int len);
1.1 deraadt 90:
1.6 markus 91: /*
92: * Finalizes and sends the packet. If the encryption key has been set,
93: * encrypts the packet before sending.
94: */
1.5 deraadt 95: void packet_send(void);
1.1 deraadt 96:
97: /* Waits until a packet has been received, and returns its type. */
1.5 deraadt 98: int packet_read(int *payload_len_ptr);
1.1 deraadt 99:
1.6 markus 100: /*
101: * Waits until a packet has been received, verifies that its type matches
102: * that given, and gives a fatal error and exits if there is a mismatch.
103: */
1.5 deraadt 104: void packet_read_expect(int *payload_len_ptr, int type);
1.1 deraadt 105:
1.6 markus 106: /*
107: * Checks if a full packet is available in the data received so far via
108: * packet_process_incoming. If so, reads the packet; otherwise returns
109: * SSH_MSG_NONE. This does not wait for data from the connection.
110: * SSH_MSG_DISCONNECT is handled specially here. Also, SSH_MSG_IGNORE
111: * messages are skipped by this function and are never returned to higher
112: * levels.
113: */
1.5 deraadt 114: int packet_read_poll(int *packet_len_ptr);
1.1 deraadt 115:
1.6 markus 116: /*
117: * Buffers the given amount of input characters. This is intended to be used
118: * together with packet_read_poll.
119: */
1.18 markus 120: void packet_process_incoming(const char *buf, u_int len);
1.1 deraadt 121:
122: /* Returns a character (0-255) from the packet data. */
1.18 markus 123: u_int packet_get_char(void);
1.1 deraadt 124:
125: /* Returns an integer from the packet data. */
1.18 markus 126: u_int packet_get_int(void);
1.1 deraadt 127:
1.6 markus 128: /*
129: * Returns an arbitrary precision integer from the packet data. The integer
130: * must have been initialized before this call.
131: */
1.5 deraadt 132: void packet_get_bignum(BIGNUM * value, int *length_ptr);
1.12 markus 133: void packet_get_bignum2(BIGNUM * value, int *length_ptr);
1.11 markus 134: char *packet_get_raw(int *length_ptr);
1.1 deraadt 135:
1.6 markus 136: /*
137: * Returns a string from the packet data. The string is allocated using
138: * xmalloc; it is the responsibility of the calling program to free it when
139: * no longer needed. The length_ptr argument may be NULL, or point to an
140: * integer into which the length of the string is stored.
141: */
1.18 markus 142: char *packet_get_string(u_int *length_ptr);
1.1 deraadt 143:
1.6 markus 144: /*
145: * Logs the error in syslog using LOG_INFO, constructs and sends a disconnect
146: * packet, closes the connection, and exits. This function never returns.
147: * The error message should not contain a newline. The total length of the
148: * message must not exceed 1024 bytes.
149: */
1.10 markus 150: void packet_disconnect(const char *fmt,...) __attribute__((format(printf, 1, 2)));
1.1 deraadt 151:
1.6 markus 152: /*
153: * Sends a diagnostic message to the other side. This message can be sent at
154: * any time (but not while constructing another message). The message is
155: * printed immediately, but only if the client is being executed in verbose
156: * mode. These messages are primarily intended to ease debugging
157: * authentication problems. The total length of the message must not exceed
158: * 1024 bytes. This will automatically call packet_write_wait. If the
159: * remote side protocol flags do not indicate that it supports SSH_MSG_DEBUG,
160: * this will do nothing.
161: */
1.10 markus 162: void packet_send_debug(const char *fmt,...) __attribute__((format(printf, 1, 2)));
1.1 deraadt 163:
1.6 markus 164: /* Checks if there is any buffered output, and tries to write some of the output. */
1.5 deraadt 165: void packet_write_poll(void);
1.1 deraadt 166:
167: /* Waits until all pending output data has been written. */
1.5 deraadt 168: void packet_write_wait(void);
1.1 deraadt 169:
170: /* Returns true if there is buffered data to write to the connection. */
1.5 deraadt 171: int packet_have_data_to_write(void);
1.1 deraadt 172:
173: /* Returns true if there is not too much data to write to the connection. */
1.5 deraadt 174: int packet_not_very_much_data_to_write(void);
1.4 markus 175:
176: /* maximum packet size, requested by client with SSH_CMSG_MAX_PACKET_SIZE */
177: extern int max_packet_size;
1.5 deraadt 178: int packet_set_maxsize(int s);
1.4 markus 179: #define packet_get_maxsize() max_packet_size
1.1 deraadt 180:
1.22 ! stevesk 181: /* Stores tty modes from the fd or tiop into current packet. */
! 182: void tty_make_modes(int fd, struct termios *tiop);
1.1 deraadt 183:
184: /* Parses tty modes for the fd from the current packet. */
1.5 deraadt 185: void tty_parse_modes(int fd, int *n_bytes_ptr);
1.1 deraadt 186:
187: #define packet_integrity_check(payload_len, expected_len, type) \
188: do { \
189: int _p = (payload_len), _e = (expected_len); \
190: if (_p != _e) { \
191: log("Packet integrity error (%d != %d) at %s:%d", \
192: _p, _e, __FILE__, __LINE__); \
193: packet_disconnect("Packet integrity error. (%d)", (type)); \
194: } \
195: } while (0)
1.8 markus 196:
1.14 markus 197: #define packet_done() \
198: do { \
199: int _len = packet_remaining(); \
200: if (_len > 0) { \
201: log("Packet integrity error (%d bytes remaining) at %s:%d", \
202: _len ,__FILE__, __LINE__); \
203: packet_disconnect("Packet integrity error."); \
204: } \
205: } while (0)
206:
1.9 markus 207: /* remote host is connected via a socket/ipv4 */
1.8 markus 208: int packet_connection_is_on_socket(void);
1.9 markus 209: int packet_connection_is_ipv4(void);
1.12 markus 210:
211: /* enable SSH2 packet format */
212: void packet_set_ssh2_format(void);
1.14 markus 213:
214: /* returns remaining payload bytes */
215: int packet_remaining(void);
1.20 markus 216:
217: /* append an ignore message */
1.21 markus 218: void packet_send_ignore(int nbytes);
219:
220: /* add an ignore message and make sure size (current+ignore) = n*sumlen */
1.20 markus 221: void packet_inject_ignore(int sumlen);
1.1 deraadt 222:
1.5 deraadt 223: #endif /* PACKET_H */