/*
- *
- * packet.c
- *
* Author: Tatu Ylonen <ylo@cs.hut.fi>
- *
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- *
- * Created: Sat Mar 18 02:40:40 1995 ylo
- *
* This file contains code implementing the packet protocol and communication
* with the other side. This same code is used both on client and server side.
*
+ * 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".
+ *
+ *
* SSH2 packet format added by Markus Friedl.
+ * Copyright (c) 2000 Markus Friedl. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
*
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "includes.h"
-RCSID("$Id$");
+RCSID("$OpenBSD: packet.c,v 1.46 2001/01/21 19:05:53 markus Exp $");
#include "xmalloc.h"
#include "buffer.h"
#include "packet.h"
#include "bufaux.h"
-#include "ssh.h"
#include "crc32.h"
-#include "cipher.h"
#include "getput.h"
#include "compress.h"
#include "channels.h"
#include "compat.h"
+#include "ssh1.h"
#include "ssh2.h"
-#include <ssl/bn.h>
-#include <ssl/dh.h>
-#include <ssl/hmac.h>
+#include <openssl/bn.h>
+#include <openssl/dh.h>
+#include <openssl/hmac.h>
#include "buffer.h"
+#include "cipher.h"
#include "kex.h"
#include "hmac.h"
+#include "log.h"
+#include "canohost.h"
#ifdef PACKET_DEBUG
#define DBG(x) x
static int cipher_type = SSH_CIPHER_NONE;
/* Protocol flags for the remote side. */
-static unsigned int remote_protocol_flags = 0;
+static u_int remote_protocol_flags = 0;
/* Encryption context for receiving data. This is only used for decryption. */
static CipherContext receive_context;
void
packet_set_ssh2_format(void)
{
- debug("use_ssh2_packet_format");
+ DBG(debug("use_ssh2_packet_format"));
use_ssh2_packet_format = 1;
}
void
packet_set_connection(int fd_in, int fd_out)
{
+ Cipher *none = cipher_by_name("none");
+ if (none == NULL)
+ fatal("packet_set_connection: cannot load cipher 'none'");
connection_in = fd_in;
connection_out = fd_out;
cipher_type = SSH_CIPHER_NONE;
- cipher_set_key(&send_context, SSH_CIPHER_NONE, (unsigned char *) "", 0, 1);
- cipher_set_key(&receive_context, SSH_CIPHER_NONE, (unsigned char *) "", 0, 0);
+ cipher_init(&send_context, none, (u_char *) "", 0, NULL, 0);
+ cipher_init(&receive_context, none, (u_char *) "", 0, NULL, 0);
if (!initialized) {
initialized = 1;
buffer_init(&input);
/* Sets remote side protocol flags. */
void
-packet_set_protocol_flags(unsigned int protocol_flags)
+packet_set_protocol_flags(u_int protocol_flags)
{
remote_protocol_flags = protocol_flags;
channel_set_options((protocol_flags & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) != 0);
/* Returns the remote protocol flags set earlier by the above function. */
-unsigned int
+u_int
packet_get_protocol_flags()
{
return remote_protocol_flags;
void
packet_encrypt(CipherContext * cc, void *dest, void *src,
- unsigned int bytes)
+ u_int bytes)
{
cipher_encrypt(cc, dest, src, bytes);
}
*/
void
-packet_decrypt(CipherContext * cc, void *dest, void *src,
- unsigned int bytes)
+packet_decrypt(CipherContext *context, void *dest, void *src, u_int bytes)
{
- int i;
-
- if ((bytes % 8) != 0)
- fatal("packet_decrypt: bad ciphertext length %d", bytes);
-
/*
* Cryptographic attack detector for ssh - Modifications for packet.c
* (C)1998 CORE-SDI, Buenos Aires Argentina Ariel Futoransky(futo@core-sdi.com)
*/
-
- if (cc->type == SSH_CIPHER_NONE || compat20) {
- i = DEATTACK_OK;
- } else {
- i = detect_attack(src, bytes, NULL);
- }
- if (i == DEATTACK_DETECTED)
+ if (!compat20 &&
+ context->cipher->number != SSH_CIPHER_NONE &&
+ detect_attack(src, bytes, NULL) == DEATTACK_DETECTED)
packet_disconnect("crc32 compensation attack: network attack detected");
- cipher_decrypt(cc, dest, src, bytes);
+ cipher_decrypt(context, dest, src, bytes);
}
/*
*/
void
-packet_set_encryption_key(const unsigned char *key, unsigned int keylen,
- int cipher)
+packet_set_encryption_key(const u_char *key, u_int keylen,
+ int number)
{
+ Cipher *cipher = cipher_by_number(number);
+ if (cipher == NULL)
+ fatal("packet_set_encryption_key: unknown cipher number %d", number);
if (keylen < 20)
- fatal("keylen too small: %d", keylen);
-
- /* All other ciphers use the same key in both directions for now. */
- cipher_set_key(&receive_context, cipher, key, keylen, 0);
- cipher_set_key(&send_context, cipher, key, keylen, 1);
+ fatal("packet_set_encryption_key: keylen too small: %d", keylen);
+ cipher_init(&receive_context, cipher, key, keylen, NULL, 0);
+ cipher_init(&send_context, cipher, key, keylen, NULL, 0);
}
/* Starts constructing a packet to send. */
/* Appends an integer to the packet data. */
void
-packet_put_int(unsigned int value)
+packet_put_int(u_int value)
{
buffer_put_int(&outgoing_packet, value);
}
/* Appends a string to packet data. */
void
-packet_put_string(const char *buf, unsigned int len)
+packet_put_string(const char *buf, u_int len)
{
buffer_put_string(&outgoing_packet, buf, len);
}
}
void
-packet_put_raw(const char *buf, unsigned int len)
+packet_put_raw(const char *buf, u_int len)
{
buffer_append(&outgoing_packet, buf, len);
}
{
char buf[8], *cp;
int i, padding, len;
- unsigned int checksum;
+ u_int checksum;
u_int32_t rand = 0;
/*
/* Compute packet length without padding (add checksum, remove padding). */
len = buffer_len(&outgoing_packet) + 4 - 8;
- /* Insert padding. */
+ /* Insert padding. Initialized to zero in packet_start1() */
padding = 8 - len % 8;
if (cipher_type != SSH_CIPHER_NONE) {
cp = buffer_ptr(&outgoing_packet);
buffer_consume(&outgoing_packet, 8 - padding);
/* Add check bytes. */
- checksum = crc32((unsigned char *) buffer_ptr(&outgoing_packet),
- buffer_len(&outgoing_packet));
+ checksum = ssh_crc32((u_char *) buffer_ptr(&outgoing_packet),
+ buffer_len(&outgoing_packet));
PUT_32BIT(buf, checksum);
buffer_append(&outgoing_packet, buf, 4);
void
packet_send2()
{
- unsigned char *macbuf = NULL;
+ u_char *macbuf = NULL;
char *cp;
- unsigned int packet_length = 0;
- unsigned int i, padlen, len;
+ u_int packet_length = 0;
+ u_int i, padlen, len;
u_int32_t rand = 0;
- static unsigned int seqnr = 0;
+ static u_int seqnr = 0;
int type;
Enc *enc = NULL;
Mac *mac = NULL;
mac = &kex->mac[MODE_OUT];
comp = &kex->comp[MODE_OUT];
}
- block_size = enc ? enc->block_size : 8;
+ block_size = enc ? enc->cipher->block_size : 8;
cp = buffer_ptr(&outgoing_packet);
type = cp[5] & 0xff;
if (padlen < 4)
padlen += block_size;
buffer_append_space(&outgoing_packet, &cp, padlen);
- if (enc && enc->type != SSH_CIPHER_NONE) {
+ if (enc && enc->cipher->number != SSH_CIPHER_NONE) {
+ /* random padding */
for (i = 0; i < padlen; i++) {
if (i % 4 == 0)
rand = arc4random();
cp[i] = rand & 0xff;
rand <<= 8;
}
+ } else {
+ /* clear padding */
+ memset(cp, 0, padlen);
}
/* packet_length includes payload, padding and padding length field */
packet_length = buffer_len(&outgoing_packet) - 4;
/* compute MAC over seqnr and packet(length fields, payload, padding) */
if (mac && mac->enabled) {
macbuf = hmac( mac->md, seqnr,
- (unsigned char *) buffer_ptr(&outgoing_packet),
+ (u_char *) buffer_ptr(&outgoing_packet),
buffer_len(&outgoing_packet),
mac->key, mac->key_len
);
- DBG(debug("done calc HMAC out #%d", seqnr));
+ DBG(debug("done calc MAC out #%d", seqnr));
}
/* encrypt packet and append to output buffer. */
buffer_append_space(&output, &cp, buffer_len(&outgoing_packet));
fprintf(stderr, "encrypted: ");
buffer_dump(&output);
#endif
- /* increment sequence number for outgoing packets */
- if (++seqnr == 0)
- log("outgoing seqnr wraps around");
+ /* increment sequence number for outgoing packets */
+ if (++seqnr == 0)
+ log("outgoing seqnr wraps around");
buffer_clear(&outgoing_packet);
if (type == SSH2_MSG_NEWKEYS) {
fatal("packet_send2: no KEX");
if (mac->md != NULL)
mac->enabled = 1;
- debug("cipher_set_key_iv send_context");
- cipher_set_key_iv(&send_context, enc->type,
- enc->key, enc->key_len,
- enc->iv, enc->iv_len);
+ DBG(debug("cipher_init send_context"));
+ cipher_init(&send_context, enc->cipher,
+ enc->key, enc->cipher->key_len,
+ enc->iv, enc->cipher->block_size);
clear_enc_keys(enc, kex->we_need);
if (comp->type != 0 && comp->enabled == 0) {
comp->enabled = 1;
DBG(debug("packet_send done"));
}
-void
-packet_send_and_wait()
-{
- packet_send();
- packet_write_wait();
-}
-
/*
* Waits until a packet has been received, and returns its type. Note that
* no other data is processed until this returns, so this function should not
for (;;) {
/* Try to read a packet from the buffer. */
type = packet_read_poll(payload_len_ptr);
- if (type == SSH_SMSG_SUCCESS
+ if (!use_ssh2_packet_format && (
+ type == SSH_SMSG_SUCCESS
|| type == SSH_SMSG_FAILURE
|| type == SSH_CMSG_EOF
- || type == SSH_CMSG_EXIT_CONFIRMATION)
+ || type == SSH_CMSG_EXIT_CONFIRMATION))
packet_integrity_check(*payload_len_ptr, 0, type);
/* If we got a packet, return it. */
if (type != SSH_MSG_NONE)
int
packet_read_poll1(int *payload_len_ptr)
{
- unsigned int len, padded_len;
- unsigned char *ucp;
+ u_int len, padded_len;
+ u_char *ucp;
char buf[8], *cp;
- unsigned int checksum, stored_checksum;
+ u_int checksum, stored_checksum;
/* Check if input size is less than minimum packet size. */
if (buffer_len(&input) < 4 + 8)
return SSH_MSG_NONE;
/* Get length of incoming packet. */
- ucp = (unsigned char *) buffer_ptr(&input);
+ ucp = (u_char *) buffer_ptr(&input);
len = GET_32BIT(ucp);
if (len < 1 + 2 + 2 || len > 256 * 1024)
packet_disconnect("Bad packet length %d.", len);
#endif
/* Compute packet checksum. */
- checksum = crc32((unsigned char *) buffer_ptr(&incoming_packet),
+ checksum = ssh_crc32((u_char *) buffer_ptr(&incoming_packet),
buffer_len(&incoming_packet) - 4);
/* Skip padding. */
packet_disconnect("packet_read_poll: len %d != buffer_len %d.",
len, buffer_len(&incoming_packet));
- ucp = (unsigned char *) buffer_ptr(&incoming_packet) + len - 4;
+ ucp = (u_char *) buffer_ptr(&incoming_packet) + len - 4;
stored_checksum = GET_32BIT(ucp);
if (checksum != stored_checksum)
packet_disconnect("Corrupted check bytes on input.");
*payload_len_ptr = buffer_len(&incoming_packet);
/* Return type. */
- return (unsigned char) buf[0];
+ return (u_char) buf[0];
}
int
packet_read_poll2(int *payload_len_ptr)
{
- unsigned int padlen, need;
- unsigned char buf[8], *macbuf;
- unsigned char *ucp;
+ u_int padlen, need;
+ u_char buf[8], *macbuf;
+ u_char *ucp;
char *cp;
- static unsigned int packet_length = 0;
- static unsigned int seqnr = 0;
+ static u_int packet_length = 0;
+ static u_int seqnr = 0;
int type;
int maclen, block_size;
Enc *enc = NULL;
comp = &kex->comp[MODE_IN];
}
maclen = mac && mac->enabled ? mac->mac_len : 0;
- block_size = enc ? enc->block_size : 8;
+ block_size = enc ? enc->cipher->block_size : 8;
if (packet_length == 0) {
/*
buffer_append_space(&incoming_packet, &cp, block_size);
packet_decrypt(&receive_context, cp, buffer_ptr(&input),
block_size);
- ucp = (unsigned char *) buffer_ptr(&incoming_packet);
+ ucp = (u_char *) buffer_ptr(&incoming_packet);
packet_length = GET_32BIT(ucp);
if (packet_length < 1 + 4 || packet_length > 256 * 1024) {
buffer_dump(&incoming_packet);
* compute MAC over seqnr and packet,
* increment sequence number for incoming packet
*/
- if (mac && mac->enabled) {
+ if (mac && mac->enabled) {
macbuf = hmac( mac->md, seqnr,
- (unsigned char *) buffer_ptr(&incoming_packet),
+ (u_char *) buffer_ptr(&incoming_packet),
buffer_len(&incoming_packet),
mac->key, mac->key_len
);
if (memcmp(macbuf, buffer_ptr(&input), mac->mac_len) != 0)
- packet_disconnect("Corrupted HMAC on input.");
- DBG(debug("HMAC #%d ok", seqnr));
+ packet_disconnect("Corrupted MAC on input.");
+ DBG(debug("MAC #%d ok", seqnr));
buffer_consume(&input, mac->mac_len);
}
- if (++seqnr == 0)
- log("incoming seqnr wraps around");
+ if (++seqnr == 0)
+ log("incoming seqnr wraps around");
/* get padlen */
cp = buffer_ptr(&incoming_packet) + 4;
packet_length = 0;
/* extract packet type */
- type = (unsigned char)buf[0];
+ type = (u_char)buf[0];
if (type == SSH2_MSG_NEWKEYS) {
if (kex==NULL || mac==NULL || enc==NULL || comp==NULL)
fatal("packet_read_poll2: no KEX");
if (mac->md != NULL)
mac->enabled = 1;
- debug("cipher_set_key_iv receive_context");
- cipher_set_key_iv(&receive_context, enc->type,
- enc->key, enc->key_len,
- enc->iv, enc->iv_len);
+ DBG(debug("cipher_init receive_context"));
+ cipher_init(&receive_context, enc->cipher,
+ enc->key, enc->cipher->key_len,
+ enc->iv, enc->cipher->block_size);
clear_enc_keys(enc, kex->we_need);
if (comp->type != 0 && comp->enabled == 0) {
comp->enabled = 1;
fprintf(stderr, "read/plain[%d]:\r\n",type);
buffer_dump(&incoming_packet);
#endif
- return (unsigned char)type;
+ return (u_char)type;
}
int
case SSH2_MSG_DISCONNECT:
reason = packet_get_int();
msg = packet_get_string(NULL);
- log("Received disconnect: %d: %.900s", reason, msg);
+ log("Received disconnect from %s: %d: %.400s", get_remote_ipaddr(),
+ reason, msg);
xfree(msg);
fatal_cleanup();
break;
break;
case SSH_MSG_DISCONNECT:
msg = packet_get_string(NULL);
- log("Received disconnect: %.900s", msg);
+ log("Received disconnect from %s: %.400s", get_remote_ipaddr(),
+ msg);
fatal_cleanup();
xfree(msg);
break;
*/
void
-packet_process_incoming(const char *buf, unsigned int len)
+packet_process_incoming(const char *buf, u_int len)
{
buffer_append(&input, buf, len);
}
/* Returns a character from the packet. */
-unsigned int
+u_int
packet_get_char()
{
char ch;
buffer_get(&incoming_packet, &ch, 1);
- return (unsigned char) ch;
+ return (u_char) ch;
}
/* Returns an integer from the packet data. */
-unsigned int
+u_int
packet_get_int()
{
return buffer_get_int(&incoming_packet);
return buffer_ptr(&incoming_packet);
}
+int
+packet_remaining(void)
+{
+ return buffer_len(&incoming_packet);
+}
+
/*
* 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
*/
char *
-packet_get_string(unsigned int *length_ptr)
+packet_get_string(u_int *length_ptr)
{
return buffer_get_string(&incoming_packet, length_ptr);
}
char buf[1024];
va_list args;
+ if (compat20 && (datafellows & SSH_BUG_DEBUG))
+ return;
+
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
- packet_start(SSH_MSG_DEBUG);
- packet_put_string(buf, strlen(buf));
+ if (compat20) {
+ packet_start(SSH2_MSG_DEBUG);
+ packet_put_char(0); /* bool: always display */
+ packet_put_cstring(buf);
+ packet_put_cstring("");
+ } else {
+ packet_start(SSH_MSG_DEBUG);
+ packet_put_cstring(buf);
+ }
packet_send();
packet_write_wait();
}
/* Informs that the current session is interactive. Sets IP flags for that. */
void
-packet_set_interactive(int interactive, int keepalives)
+packet_set_interactive(int interactive)
{
+ static int called = 0;
+ int lowdelay = IPTOS_LOWDELAY;
+ int throughput = IPTOS_THROUGHPUT;
int on = 1;
+ if (called)
+ return;
+ called = 1;
+
/* Record that we are in interactive mode. */
interactive_mode = interactive;
/* Only set socket options if using a socket. */
if (!packet_connection_is_on_socket())
return;
- if (keepalives) {
- /* Set keepalives if requested. */
- if (setsockopt(connection_in, SOL_SOCKET, SO_KEEPALIVE, (void *) &on,
- sizeof(on)) < 0)
- error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
- }
/*
- * IPTOS_LOWDELAY, TCP_NODELAY and IPTOS_THROUGHPUT are IPv4 only
+ * IPTOS_LOWDELAY and IPTOS_THROUGHPUT are IPv4 only
*/
- if (!packet_connection_is_ipv4())
- return;
if (interactive) {
/*
* Set IP options for an interactive connection. Use
* IPTOS_LOWDELAY and TCP_NODELAY.
*/
- int lowdelay = IPTOS_LOWDELAY;
- if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *) &lowdelay,
- sizeof(lowdelay)) < 0)
- error("setsockopt IPTOS_LOWDELAY: %.100s", strerror(errno));
+#if defined(IP_TOS) && !defined(IP_TOS_IS_BROKEN)
+ if (packet_connection_is_ipv4()) {
+ if (setsockopt(connection_in, IPPROTO_IP, IP_TOS,
+ (void *) &lowdelay, sizeof(lowdelay)) < 0)
+ error("setsockopt IPTOS_LOWDELAY: %.100s",
+ strerror(errno));
+ }
+#endif
if (setsockopt(connection_in, IPPROTO_TCP, TCP_NODELAY, (void *) &on,
sizeof(on)) < 0)
error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
- } else {
+ } else if (packet_connection_is_ipv4()) {
/*
* Set IP options for a non-interactive connection. Use
* IPTOS_THROUGHPUT.
*/
- int throughput = IPTOS_THROUGHPUT;
+#if defined(IP_TOS) && !defined(IP_TOS_IS_BROKEN)
if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *) &throughput,
sizeof(throughput)) < 0)
error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno));
+#endif
}
}
andersk / openssh.git / blobdiff