*/
#include "includes.h"
-RCSID("$OpenBSD: packet.c,v 1.72 2001/11/10 13:37:20 markus Exp $");
+RCSID("$OpenBSD: packet.c,v 1.90 2002/02/27 21:23:13 stevesk Exp $");
#include "xmalloc.h"
#include "buffer.h"
#include "mac.h"
#include "log.h"
#include "canohost.h"
+#include "misc.h"
#ifdef PACKET_DEBUG
#define DBG(x) x
fatal("packet_set_connection: cannot load cipher 'none'");
connection_in = fd_in;
connection_out = fd_out;
- cipher_init(&send_context, none, (u_char *) "", 0, NULL, 0);
- cipher_init(&receive_context, none, (u_char *) "", 0, NULL, 0);
+ cipher_init(&send_context, none, "", 0, NULL, 0, CIPHER_ENCRYPT);
+ cipher_init(&receive_context, none, "", 0, NULL, 0, CIPHER_DECRYPT);
newkeys[MODE_IN] = newkeys[MODE_OUT] = NULL;
if (!initialized) {
initialized = 1;
/* Returns 1 if remote host is connected via socket, 0 if not. */
int
-packet_connection_is_on_socket()
+packet_connection_is_on_socket(void)
{
struct sockaddr_storage from, to;
socklen_t fromlen, tolen;
/* returns 1 if connection is via ipv4 */
int
-packet_connection_is_ipv4()
+packet_connection_is_ipv4(void)
{
struct sockaddr_storage to;
socklen_t tolen = sizeof(to);
/* Sets the connection into non-blocking mode. */
void
-packet_set_nonblocking()
+packet_set_nonblocking(void)
{
/* Set the socket into non-blocking mode. */
if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0)
/* Returns the socket used for reading. */
int
-packet_get_connection_in()
+packet_get_connection_in(void)
{
return connection_in;
}
/* Returns the descriptor used for writing. */
int
-packet_get_connection_out()
+packet_get_connection_out(void)
{
return connection_out;
}
/* Closes the connection and clears and frees internal data structures. */
void
-packet_close()
+packet_close(void)
{
if (!initialized)
return;
buffer_free(&compression_buffer);
buffer_compress_uninit();
}
+ cipher_cleanup(&send_context);
+ cipher_cleanup(&receive_context);
}
/* Sets remote side protocol flags. */
/* Returns the remote protocol flags set earlier by the above function. */
u_int
-packet_get_protocol_flags()
+packet_get_protocol_flags(void)
{
return remote_protocol_flags;
}
fatal("packet_set_encryption_key: unknown cipher number %d", number);
if (keylen < 20)
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);
+ cipher_init(&send_context, cipher, key, keylen, NULL, 0, CIPHER_ENCRYPT);
+ cipher_init(&receive_context, cipher, key, keylen, NULL, 0, CIPHER_DECRYPT);
}
/* Start constructing a packet to send. */
buffer_put_int(&outgoing_packet, value);
}
void
-packet_put_string(const char *buf, u_int len)
+packet_put_string(const void *buf, u_int len)
{
buffer_put_string(&outgoing_packet, buf, len);
}
buffer_put_cstring(&outgoing_packet, str);
}
void
-packet_put_raw(const char *buf, u_int len)
+packet_put_raw(const void *buf, u_int len)
{
buffer_append(&outgoing_packet, buf, len);
}
static void
packet_send1(void)
{
- char buf[8], *cp;
+ u_char buf[8], *cp;
int i, padding, len;
u_int checksum;
u_int32_t rand = 0;
buffer_compress(&outgoing_packet, &compression_buffer);
buffer_clear(&outgoing_packet);
buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer),
- buffer_len(&compression_buffer));
+ buffer_len(&compression_buffer));
}
/* Compute packet length without padding (add checksum, remove padding). */
len = buffer_len(&outgoing_packet) + 4 - 8;
/* Insert padding. Initialized to zero in packet_start1() */
padding = 8 - len % 8;
- if (send_context.cipher->number != SSH_CIPHER_NONE) {
+ if (!send_context.plaintext) {
cp = buffer_ptr(&outgoing_packet);
for (i = 0; i < padding; i++) {
if (i % 4 == 0)
buffer_consume(&outgoing_packet, 8 - padding);
/* Add check bytes. */
- checksum = ssh_crc32((u_char *) buffer_ptr(&outgoing_packet),
+ checksum = ssh_crc32(buffer_ptr(&outgoing_packet),
buffer_len(&outgoing_packet));
PUT_32BIT(buf, checksum);
buffer_append(&outgoing_packet, buf, 4);
/* Append to output. */
PUT_32BIT(buf, len);
buffer_append(&output, buf, 4);
- buffer_append_space(&output, &cp, buffer_len(&outgoing_packet));
- cipher_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet),
- buffer_len(&outgoing_packet));
+ cp = buffer_append_space(&output, buffer_len(&outgoing_packet));
+ cipher_crypt(&send_context, cp, buffer_ptr(&outgoing_packet),
+ buffer_len(&outgoing_packet));
#ifdef PACKET_DEBUG
fprintf(stderr, "encrypted: ");
Mac *mac;
Comp *comp;
CipherContext *cc;
+ int encrypt;
debug("newkeys: mode %d", mode);
- cc = (mode == MODE_OUT) ? &send_context : &receive_context;
+ if (mode == MODE_OUT) {
+ cc = &send_context;
+ encrypt = CIPHER_ENCRYPT;
+ } else {
+ cc = &receive_context;
+ encrypt = CIPHER_DECRYPT;
+ }
if (newkeys[mode] != NULL) {
debug("newkeys: rekeying");
- /* todo: free old keys, reset compression/cipher-ctxt; */
- memset(cc, 0, sizeof(*cc));
+ cipher_cleanup(cc);
enc = &newkeys[mode]->enc;
mac = &newkeys[mode]->mac;
comp = &newkeys[mode]->comp;
if (mac->md != NULL)
mac->enabled = 1;
DBG(debug("cipher_init_context: %d", mode));
- cipher_init(cc, enc->cipher, enc->key, enc->cipher->key_len,
- enc->iv, enc->cipher->block_size);
- memset(enc->iv, 0, enc->cipher->block_size);
- memset(enc->key, 0, enc->cipher->key_len);
+ cipher_init(cc, enc->cipher, enc->key, enc->key_len,
+ enc->iv, enc->block_size, encrypt);
+ memset(enc->iv, 0, enc->block_size);
+ memset(enc->key, 0, enc->key_len);
if (comp->type != 0 && comp->enabled == 0) {
packet_init_compression();
if (mode == MODE_OUT)
packet_send2(void)
{
static u_int32_t seqnr = 0;
- u_char type, *ucp, *macbuf = NULL;
+ u_char type, *cp, *macbuf = NULL;
u_char padlen, pad;
- char *cp;
u_int packet_length = 0;
u_int i, len;
u_int32_t rand = 0;
mac = &newkeys[MODE_OUT]->mac;
comp = &newkeys[MODE_OUT]->comp;
}
- block_size = enc ? enc->cipher->block_size : 8;
+ block_size = enc ? enc->block_size : 8;
- ucp = (u_char *) buffer_ptr(&outgoing_packet);
- type = ucp[5];
+ cp = buffer_ptr(&outgoing_packet);
+ type = cp[5];
#ifdef PACKET_DEBUG
fprintf(stderr, "plain: ");
padlen += pad;
extra_pad = 0;
}
- buffer_append_space(&outgoing_packet, &cp, padlen);
- if (enc && enc->cipher->number != SSH_CIPHER_NONE) {
+ cp = buffer_append_space(&outgoing_packet, padlen);
+ if (enc && !send_context.plaintext) {
/* random padding */
for (i = 0; i < padlen; i++) {
if (i % 4 == 0)
}
/* packet_length includes payload, padding and padding length field */
packet_length = buffer_len(&outgoing_packet) - 4;
- ucp = (u_char *)buffer_ptr(&outgoing_packet);
- PUT_32BIT(ucp, packet_length);
- ucp[4] = padlen;
+ cp = buffer_ptr(&outgoing_packet);
+ PUT_32BIT(cp, packet_length);
+ cp[4] = padlen;
DBG(debug("send: len %d (includes padlen %d)", packet_length+4, padlen));
/* compute MAC over seqnr and packet(length fields, payload, padding) */
if (mac && mac->enabled) {
macbuf = mac_compute(mac, seqnr,
- (u_char *) buffer_ptr(&outgoing_packet),
+ buffer_ptr(&outgoing_packet),
buffer_len(&outgoing_packet));
DBG(debug("done calc MAC out #%d", seqnr));
}
/* encrypt packet and append to output buffer. */
- buffer_append_space(&output, &cp, buffer_len(&outgoing_packet));
- cipher_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet),
+ cp = buffer_append_space(&output, buffer_len(&outgoing_packet));
+ cipher_crypt(&send_context, cp, buffer_ptr(&outgoing_packet),
buffer_len(&outgoing_packet));
/* append unencrypted MAC */
if (mac && mac->enabled)
}
void
-packet_send()
+packet_send(void)
{
if (compat20)
packet_send2();
*/
int
-packet_read(int *payload_len_ptr)
+packet_read_seqnr(u_int32_t *seqnr_p)
{
int type, len;
fd_set *setp;
/* Stay in the loop until we have received a complete packet. */
for (;;) {
/* Try to read a packet from the buffer. */
- type = packet_read_poll(payload_len_ptr);
+ type = packet_read_poll_seqnr(seqnr_p);
if (!compat20 && (
type == SSH_SMSG_SUCCESS
|| type == SSH_SMSG_FAILURE
|| type == SSH_CMSG_EOF
|| type == SSH_CMSG_EXIT_CONFIRMATION))
- packet_integrity_check(*payload_len_ptr, 0, type);
+ packet_check_eom();
/* If we got a packet, return it. */
if (type != SSH_MSG_NONE) {
xfree(setp);
/* NOTREACHED */
}
+int
+packet_read(void)
+{
+ return packet_read_seqnr(NULL);
+}
+
/*
* 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 expected_type)
+packet_read_expect(int expected_type)
{
int type;
- type = packet_read(payload_len_ptr);
+ type = packet_read();
if (type != expected_type)
packet_disconnect("Protocol error: expected packet type %d, got %d",
expected_type, type);
* SSH_MSG_DISCONNECT is handled specially here. Also,
* SSH_MSG_IGNORE messages are skipped by this function and are never returned
* to higher levels.
- *
- * The returned payload_len does include space consumed by:
- * Packet length
- * Padding
- * Packet type
- * Check bytes
*/
static int
-packet_read_poll1(int *payload_len_ptr)
+packet_read_poll1(void)
{
u_int len, padded_len;
- u_char *ucp, type;
- char *cp;
+ u_char *cp, type;
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 = (u_char *) buffer_ptr(&input);
- len = GET_32BIT(ucp);
+ cp = buffer_ptr(&input);
+ len = GET_32BIT(cp);
if (len < 1 + 2 + 2 || len > 256 * 1024)
packet_disconnect("Bad packet length %d.", len);
padded_len = (len + 8) & ~7;
* (C)1998 CORE-SDI, Buenos Aires Argentina
* Ariel Futoransky(futo@core-sdi.com)
*/
- if (receive_context.cipher->number != SSH_CIPHER_NONE &&
+ if (!receive_context.plaintext &&
detect_attack(buffer_ptr(&input), padded_len, NULL) == DEATTACK_DETECTED)
packet_disconnect("crc32 compensation attack: network attack detected");
/* Decrypt data to incoming_packet. */
buffer_clear(&incoming_packet);
- buffer_append_space(&incoming_packet, &cp, padded_len);
- cipher_decrypt(&receive_context, cp, buffer_ptr(&input), padded_len);
+ cp = buffer_append_space(&incoming_packet, padded_len);
+ cipher_crypt(&receive_context, cp, buffer_ptr(&input), padded_len);
buffer_consume(&input, padded_len);
#endif
/* Compute packet checksum. */
- checksum = ssh_crc32((u_char *) buffer_ptr(&incoming_packet),
+ checksum = ssh_crc32(buffer_ptr(&incoming_packet),
buffer_len(&incoming_packet) - 4);
/* Skip padding. */
/* Test check bytes. */
if (len != buffer_len(&incoming_packet))
- packet_disconnect("packet_read_poll: len %d != buffer_len %d.",
+ packet_disconnect("packet_read_poll1: len %d != buffer_len %d.",
len, buffer_len(&incoming_packet));
- ucp = (u_char *) buffer_ptr(&incoming_packet) + len - 4;
- stored_checksum = GET_32BIT(ucp);
+ cp = (u_char *)buffer_ptr(&incoming_packet) + len - 4;
+ stored_checksum = GET_32BIT(cp);
if (checksum != stored_checksum)
packet_disconnect("Corrupted check bytes on input.");
buffer_consume_end(&incoming_packet, 4);
buffer_len(&compression_buffer));
}
type = buffer_get_char(&incoming_packet);
- *payload_len_ptr = buffer_len(&incoming_packet);
return type;
}
static int
-packet_read_poll2(int *payload_len_ptr)
+packet_read_poll2(u_int32_t *seqnr_p)
{
static u_int32_t seqnr = 0;
static u_int packet_length = 0;
u_int padlen, need;
- u_char *macbuf, *ucp, type;
- char *cp;
+ u_char *macbuf, *cp, type;
int maclen, block_size;
Enc *enc = NULL;
Mac *mac = NULL;
comp = &newkeys[MODE_IN]->comp;
}
maclen = mac && mac->enabled ? mac->mac_len : 0;
- block_size = enc ? enc->cipher->block_size : 8;
+ block_size = enc ? enc->block_size : 8;
if (packet_length == 0) {
/*
if (buffer_len(&input) < block_size)
return SSH_MSG_NONE;
buffer_clear(&incoming_packet);
- buffer_append_space(&incoming_packet, &cp, block_size);
- cipher_decrypt(&receive_context, cp, buffer_ptr(&input),
+ cp = buffer_append_space(&incoming_packet, block_size);
+ cipher_crypt(&receive_context, cp, buffer_ptr(&input),
block_size);
- ucp = (u_char *) buffer_ptr(&incoming_packet);
- packet_length = GET_32BIT(ucp);
+ cp = buffer_ptr(&incoming_packet);
+ packet_length = GET_32BIT(cp);
if (packet_length < 1 + 4 || packet_length > 256 * 1024) {
buffer_dump(&incoming_packet);
packet_disconnect("Bad packet length %d.", packet_length);
fprintf(stderr, "read_poll enc/full: ");
buffer_dump(&input);
#endif
- buffer_append_space(&incoming_packet, &cp, need);
- cipher_decrypt(&receive_context, cp, buffer_ptr(&input), need);
+ cp = buffer_append_space(&incoming_packet, need);
+ cipher_crypt(&receive_context, cp, buffer_ptr(&input), need);
buffer_consume(&input, need);
/*
* compute MAC over seqnr and packet,
*/
if (mac && mac->enabled) {
macbuf = mac_compute(mac, seqnr,
- (u_char *) buffer_ptr(&incoming_packet),
+ buffer_ptr(&incoming_packet),
buffer_len(&incoming_packet));
if (memcmp(macbuf, buffer_ptr(&input), mac->mac_len) != 0)
packet_disconnect("Corrupted MAC on input.");
DBG(debug("MAC #%d ok", seqnr));
buffer_consume(&input, mac->mac_len);
}
+ if (seqnr_p != NULL)
+ *seqnr_p = seqnr;
if (++seqnr == 0)
log("incoming seqnr wraps around");
/* get padlen */
- cp = buffer_ptr(&incoming_packet) + 4;
- padlen = (u_char) *cp;
+ cp = buffer_ptr(&incoming_packet);
+ padlen = cp[4];
DBG(debug("input: padlen %d", padlen));
if (padlen < 4)
packet_disconnect("Corrupted padlen %d on input.", padlen);
type = buffer_get_char(&incoming_packet);
if (type == SSH2_MSG_NEWKEYS)
set_newkeys(MODE_IN);
- *payload_len_ptr = buffer_len(&incoming_packet);
#ifdef PACKET_DEBUG
fprintf(stderr, "read/plain[%d]:\r\n", type);
buffer_dump(&incoming_packet);
}
int
-packet_read_poll(int *payload_len_ptr)
+packet_read_poll_seqnr(u_int32_t *seqnr_p)
{
- int reason;
+ int reason, seqnr;
u_char type;
char *msg;
for (;;) {
if (compat20) {
- type = packet_read_poll2(payload_len_ptr);
+ type = packet_read_poll2(seqnr_p);
if (type)
DBG(debug("received packet type %d", type));
- switch(type) {
+ switch (type) {
case SSH2_MSG_IGNORE:
break;
case SSH2_MSG_DEBUG:
xfree(msg);
fatal_cleanup();
break;
+ case SSH2_MSG_UNIMPLEMENTED:
+ seqnr = packet_get_int();
+ debug("Received SSH2_MSG_UNIMPLEMENTED for %d", seqnr);
+ break;
default:
return type;
break;
}
} else {
- type = packet_read_poll1(payload_len_ptr);
- switch(type) {
+ type = packet_read_poll1();
+ switch (type) {
case SSH_MSG_IGNORE:
break;
case SSH_MSG_DEBUG:
}
}
+int
+packet_read_poll(void)
+{
+ return packet_read_poll_seqnr(NULL);
+}
+
/*
* Buffers the given amount of input characters. This is intended to be used
* together with packet_read_poll.
/* Returns a character from the packet. */
u_int
-packet_get_char()
+packet_get_char(void)
{
char ch;
buffer_get(&incoming_packet, &ch, 1);
/* Returns an integer from the packet data. */
u_int
-packet_get_int()
+packet_get_int(void)
{
return buffer_get_int(&incoming_packet);
}
*/
void
-packet_get_bignum(BIGNUM * value, int *length_ptr)
+packet_get_bignum(BIGNUM * value)
{
- *length_ptr = buffer_get_bignum(&incoming_packet, value);
+ buffer_get_bignum(&incoming_packet, value);
}
void
-packet_get_bignum2(BIGNUM * value, int *length_ptr)
+packet_get_bignum2(BIGNUM * value)
{
- *length_ptr = buffer_get_bignum2(&incoming_packet, value);
+ buffer_get_bignum2(&incoming_packet, value);
}
-char *
+void *
packet_get_raw(int *length_ptr)
{
int bytes = buffer_len(&incoming_packet);
* integer into which the length of the string is stored.
*/
-char *
+void *
packet_get_string(u_int *length_ptr)
{
return buffer_get_string(&incoming_packet, length_ptr);
}
+/* Clears incoming data buffer */
+
+void packet_get_all(void)
+{
+ buffer_clear(&incoming_packet);
+}
+
/*
* Sends a diagnostic message from the server to the client. This message
* can be sent at any time (but not while constructing another message). The
/* Checks if there is any buffered output, and tries to write some of the output. */
void
-packet_write_poll()
+packet_write_poll(void)
{
int len = buffer_len(&output);
if (len > 0) {
*/
void
-packet_write_wait()
+packet_write_wait(void)
{
fd_set *setp;
/* Returns true if there is buffered data to write to the connection. */
int
-packet_have_data_to_write()
+packet_have_data_to_write(void)
{
return buffer_len(&output) != 0;
}
/* Returns true if there is not too much data to write to the connection. */
int
-packet_not_very_much_data_to_write()
+packet_not_very_much_data_to_write(void)
{
if (interactive_mode)
return buffer_len(&output) < 16384;
int lowdelay = IPTOS_LOWDELAY;
int throughput = IPTOS_THROUGHPUT;
#endif
- int on = 1;
if (called)
return;
#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)
+ &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));
+ set_nodelay(connection_in);
} else if (packet_connection_is_ipv4()) {
/*
* Set IP options for a non-interactive connection. Use
* IPTOS_THROUGHPUT.
*/
#if defined(IP_TOS) && !defined(IP_TOS_IS_BROKEN)
- if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *) &throughput,
+ if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, &throughput,
sizeof(throughput)) < 0)
error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno));
#endif
/* Returns true if the current connection is interactive. */
int
-packet_is_interactive()
+packet_is_interactive(void)
{
return interactive_mode;
}
packet_start(compat20 ? SSH2_MSG_IGNORE : SSH_MSG_IGNORE);
packet_put_int(nbytes);
- for(i = 0; i < nbytes; i++) {
+ for (i = 0; i < nbytes; i++) {
if (i % 4 == 0)
rand = arc4random();
packet_put_char(rand & 0xff);