*/
#include "includes.h"
-RCSID("$OpenBSD: packet.c,v 1.114 2004/06/14 01:44:39 djm Exp $");
-
+RCSID("$OpenBSD: packet.c,v 1.121 2006/02/08 14:38:18 stevesk Exp $");
+
#include "openbsd-compat/sys-queue.h"
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
#include "xmalloc.h"
#include "buffer.h"
/* Set to true if the connection is interactive. */
static int interactive_mode = 0;
+/* Set to true if we are the server side. */
+static int server_side = 0;
+
+/* Set to true if we are authenticated. */
+static int after_authentication = 0;
+
/* Session key information for Encryption and MAC */
Newkeys *newkeys[MODE_MAX];
static struct packet_state {
u_char buf[8], *cp;
int i, padding, len;
u_int checksum;
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
/*
* If using packet compression, compress the payload of the outgoing
cp = buffer_ptr(&outgoing_packet);
for (i = 0; i < padding; i++) {
if (i % 4 == 0)
- rand = arc4random();
- cp[7 - i] = rand & 0xff;
- rand >>= 8;
+ rnd = arc4random();
+ cp[7 - i] = rnd & 0xff;
+ rnd >>= 8;
}
}
buffer_consume(&outgoing_packet, 8 - padding);
buffer_clear(&outgoing_packet);
/*
- * Note that the packet is now only buffered in output. It won\'t be
+ * Note that the packet is now only buffered in output. It won't be
* actually sent until packet_write_wait or packet_write_poll is
* called.
*/
Comp *comp;
CipherContext *cc;
u_int64_t *max_blocks;
- int encrypt;
+ int crypt_type;
debug2("set_newkeys: mode %d", mode);
if (mode == MODE_OUT) {
cc = &send_context;
- encrypt = CIPHER_ENCRYPT;
+ crypt_type = CIPHER_ENCRYPT;
p_send.packets = p_send.blocks = 0;
max_blocks = &max_blocks_out;
} else {
cc = &receive_context;
- encrypt = CIPHER_DECRYPT;
+ crypt_type = CIPHER_DECRYPT;
p_read.packets = p_read.blocks = 0;
max_blocks = &max_blocks_in;
}
mac->enabled = 1;
DBG(debug("cipher_init_context: %d", mode));
cipher_init(cc, enc->cipher, enc->key, enc->key_len,
- enc->iv, enc->block_size, encrypt);
+ enc->iv, enc->block_size, crypt_type);
/* Deleting the keys does not gain extra security */
/* memset(enc->iv, 0, enc->block_size);
memset(enc->key, 0, enc->key_len); */
- if (comp->type != 0 && comp->enabled == 0) {
+ if ((comp->type == COMP_ZLIB ||
+ (comp->type == COMP_DELAYED && after_authentication)) &&
+ comp->enabled == 0) {
packet_init_compression();
if (mode == MODE_OUT)
buffer_compress_init_send(6);
*max_blocks = MIN(*max_blocks, rekey_limit / enc->block_size);
}
+/*
+ * Delayed compression for SSH2 is enabled after authentication:
+ * This happans on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
+ * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
+ */
+static void
+packet_enable_delayed_compress(void)
+{
+ Comp *comp = NULL;
+ int mode;
+
+ /*
+ * Remember that we are past the authentication step, so rekeying
+ * with COMP_DELAYED will turn on compression immediately.
+ */
+ after_authentication = 1;
+ for (mode = 0; mode < MODE_MAX; mode++) {
+ comp = &newkeys[mode]->comp;
+ if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
+ packet_init_compression();
+ if (mode == MODE_OUT)
+ buffer_compress_init_send(6);
+ else
+ buffer_compress_init_recv();
+ comp->enabled = 1;
+ }
+ }
+}
+
/*
* Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
*/
u_char padlen, pad;
u_int packet_length = 0;
u_int i, len;
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
Enc *enc = NULL;
Mac *mac = NULL;
Comp *comp = NULL;
/* random padding */
for (i = 0; i < padlen; i++) {
if (i % 4 == 0)
- rand = arc4random();
- cp[i] = rand & 0xff;
- rand >>= 8;
+ rnd = arc4random();
+ cp[i] = rnd & 0xff;
+ rnd >>= 8;
}
} else {
/* clear padding */
if (type == SSH2_MSG_NEWKEYS)
set_newkeys(MODE_OUT);
+ else if (type == SSH2_MSG_USERAUTH_SUCCESS && server_side)
+ packet_enable_delayed_compress();
}
static void
buffer_len(&compression_buffer));
}
type = buffer_get_char(&incoming_packet);
+ if (type < SSH_MSG_MIN || type > SSH_MSG_MAX)
+ packet_disconnect("Invalid ssh1 packet type: %d", type);
return type;
}
static u_int packet_length = 0;
u_int padlen, need;
u_char *macbuf, *cp, type;
- int maclen, block_size;
+ u_int maclen, block_size;
Enc *enc = NULL;
Mac *mac = NULL;
Comp *comp = NULL;
* return length of payload (without type field)
*/
type = buffer_get_char(&incoming_packet);
+ if (type < SSH2_MSG_MIN || type >= SSH2_MSG_LOCAL_MIN)
+ packet_disconnect("Invalid ssh2 packet type: %d", type);
if (type == SSH2_MSG_NEWKEYS)
set_newkeys(MODE_IN);
+ else if (type == SSH2_MSG_USERAUTH_SUCCESS && !server_side)
+ packet_enable_delayed_compress();
#ifdef PACKET_DEBUG
fprintf(stderr, "read/plain[%d]:\r\n", type);
buffer_dump(&incoming_packet);
}
void *
-packet_get_raw(int *length_ptr)
+packet_get_raw(u_int *length_ptr)
{
- int bytes = buffer_len(&incoming_packet);
+ u_int bytes = buffer_len(&incoming_packet);
if (length_ptr != NULL)
*length_ptr = bytes;
void
packet_send_ignore(int nbytes)
{
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
int i;
packet_start(compat20 ? SSH2_MSG_IGNORE : SSH_MSG_IGNORE);
packet_put_int(nbytes);
for (i = 0; i < nbytes; i++) {
if (i % 4 == 0)
- rand = arc4random();
- packet_put_char(rand & 0xff);
- rand >>= 8;
+ rnd = arc4random();
+ packet_put_char(rnd & 0xff);
+ rnd >>= 8;
}
}
{
rekey_limit = bytes;
}
+
+void
+packet_set_server(void)
+{
+ server_side = 1;
+}
+
+void
+packet_set_authenticated(void)
+{
+ after_authentication = 1;
+}
andersk / openssh.git / blobdiff