- (djm) OpenBSD CVS Sync
- markus@cvs.openbsd.org 2003/04/02 09:48:07
[clientloop.c monitor.c monitor_wrap.c packet.c packet.h readconf.c]
[readconf.h serverloop.c sshconnect2.c]
reapply rekeying chage, tested by henning@, ok djm@
diff --git a/ChangeLog b/ChangeLog
index afc34a2..140a176 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,11 @@
- (djm) Bug #539: Specify creation mode with O_CREAT for lastlog. Report
from matth@eecs.berkeley.edu
- (djm) Make the spec work with Redhat 9.0 (which renames sharutils)
+ - (djm) OpenBSD CVS Sync
+ - markus@cvs.openbsd.org 2003/04/02 09:48:07
+ [clientloop.c monitor.c monitor_wrap.c packet.c packet.h readconf.c]
+ [readconf.h serverloop.c sshconnect2.c]
+ reapply rekeying chage, tested by henning@, ok djm@
20030402
- (bal) if IP_TOS is not found or broken don't try to compile in
@@ -1304,4 +1309,4 @@
save auth method before monitor_reset_key_state(); bugzilla bug #284;
ok provos@
-$Id: ChangeLog,v 1.2651 2003/04/09 09:41:25 djm Exp $
+$Id: ChangeLog,v 1.2652 2003/04/09 10:50:06 djm Exp $
diff --git a/clientloop.c b/clientloop.c
index af207c0..a40019d 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -59,7 +59,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: clientloop.c,v 1.107 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: clientloop.c,v 1.108 2003/04/02 09:48:07 markus Exp $");
#include "ssh.h"
#include "ssh1.h"
@@ -968,9 +968,8 @@
/* Do channel operations unless rekeying in progress. */
if (!rekeying) {
channel_after_select(readset, writeset);
-
- if (need_rekeying) {
- debug("user requests rekeying");
+ if (need_rekeying || packet_need_rekeying()) {
+ debug("need rekeying");
xxx_kex->done = 0;
kex_send_kexinit(xxx_kex);
need_rekeying = 0;
diff --git a/monitor.c b/monitor.c
index bcd007e..4cd10a1 100644
--- a/monitor.c
+++ b/monitor.c
@@ -25,7 +25,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: monitor.c,v 1.36 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: monitor.c,v 1.37 2003/04/02 09:48:07 markus Exp $");
#include <openssl/dh.h>
@@ -1497,6 +1497,8 @@
Buffer m;
u_char *blob, *p;
u_int bloblen, plen;
+ u_int32_t seqnr, packets;
+ u_int64_t blocks;
debug3("%s: Waiting for new keys", __func__);
@@ -1526,8 +1528,14 @@
xfree(blob);
/* Now get sequence numbers for the packets */
- packet_set_seqnr(MODE_OUT, buffer_get_int(&m));
- packet_set_seqnr(MODE_IN, buffer_get_int(&m));
+ seqnr = buffer_get_int(&m);
+ blocks = buffer_get_int64(&m);
+ packets = buffer_get_int(&m);
+ packet_set_state(MODE_OUT, seqnr, blocks, packets);
+ seqnr = buffer_get_int(&m);
+ blocks = buffer_get_int64(&m);
+ packets = buffer_get_int(&m);
+ packet_set_state(MODE_IN, seqnr, blocks, packets);
skip:
/* Get the key context */
diff --git a/monitor_wrap.c b/monitor_wrap.c
index c971413..f674ef7 100644
--- a/monitor_wrap.c
+++ b/monitor_wrap.c
@@ -25,7 +25,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: monitor_wrap.c,v 1.24 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: monitor_wrap.c,v 1.25 2003/04/02 09:48:07 markus Exp $");
#include <openssl/bn.h>
#include <openssl/dh.h>
@@ -520,6 +520,8 @@
Buffer m;
u_char *blob, *p;
u_int bloblen, plen;
+ u_int32_t seqnr, packets;
+ u_int64_t blocks;
buffer_init(&m);
@@ -568,8 +570,14 @@
buffer_put_string(&m, blob, bloblen);
xfree(blob);
- buffer_put_int(&m, packet_get_seqnr(MODE_OUT));
- buffer_put_int(&m, packet_get_seqnr(MODE_IN));
+ packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
+ buffer_put_int(&m, seqnr);
+ buffer_put_int64(&m, blocks);
+ buffer_put_int(&m, packets);
+ packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
+ buffer_put_int(&m, seqnr);
+ buffer_put_int64(&m, blocks);
+ buffer_put_int(&m, packets);
debug3("%s: New keys have been sent", __func__);
skip:
diff --git a/packet.c b/packet.c
index 254e452..9887d25 100644
--- a/packet.c
+++ b/packet.c
@@ -37,7 +37,9 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: packet.c,v 1.104 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: packet.c,v 1.105 2003/04/02 09:48:07 markus Exp $");
+
+#include <sys/queue.h>
#include "xmalloc.h"
#include "buffer.h"
@@ -116,8 +118,14 @@
/* Session key information for Encryption and MAC */
Newkeys *newkeys[MODE_MAX];
-static u_int32_t read_seqnr = 0;
-static u_int32_t send_seqnr = 0;
+static struct packet_state {
+ u_int32_t seqnr;
+ u_int32_t packets;
+ u_int64_t blocks;
+} p_read, p_send;
+
+static u_int64_t max_blocks_in, max_blocks_out;
+static u_int32_t rekey_limit;
/* Session key for protocol v1 */
static u_char ssh1_key[SSH_SESSION_KEY_LENGTH];
@@ -126,6 +134,13 @@
/* roundup current message to extra_pad bytes */
static u_char extra_pad = 0;
+struct packet {
+ TAILQ_ENTRY(packet) next;
+ u_char type;
+ Buffer payload;
+};
+TAILQ_HEAD(, packet) outgoing;
+
/*
* Sets the descriptors used for communication. Disables encryption until
* packet_set_encryption_key is called.
@@ -148,6 +163,7 @@
buffer_init(&output);
buffer_init(&outgoing_packet);
buffer_init(&incoming_packet);
+ TAILQ_INIT(&outgoing);
}
/* Kludge: arrange the close function to be called from fatal(). */
fatal_add_cleanup((void (*) (void *)) packet_close, NULL);
@@ -254,22 +270,26 @@
return (cipher_get_number(receive_context.cipher));
}
-
-u_int32_t
-packet_get_seqnr(int mode)
+void
+packet_get_state(int mode, u_int32_t *seqnr, u_int64_t *blocks, u_int32_t *packets)
{
- return (mode == MODE_IN ? read_seqnr : send_seqnr);
+ struct packet_state *state;
+
+ state = (mode == MODE_IN) ? &p_read : &p_send;
+ *seqnr = state->seqnr;
+ *blocks = state->blocks;
+ *packets = state->packets;
}
void
-packet_set_seqnr(int mode, u_int32_t seqnr)
+packet_set_state(int mode, u_int32_t seqnr, u_int64_t blocks, u_int32_t packets)
{
- if (mode == MODE_IN)
- read_seqnr = seqnr;
- else if (mode == MODE_OUT)
- send_seqnr = seqnr;
- else
- fatal("packet_set_seqnr: bad mode %d", mode);
+ struct packet_state *state;
+
+ state = (mode == MODE_IN) ? &p_read : &p_send;
+ state->seqnr = seqnr;
+ state->blocks = blocks;
+ state->packets = packets;
}
/* returns 1 if connection is via ipv4 */
@@ -562,6 +582,7 @@
Mac *mac;
Comp *comp;
CipherContext *cc;
+ u_int64_t *max_blocks;
int encrypt;
debug2("set_newkeys: mode %d", mode);
@@ -569,9 +590,13 @@
if (mode == MODE_OUT) {
cc = &send_context;
encrypt = CIPHER_ENCRYPT;
+ p_send.packets = p_send.blocks = 0;
+ max_blocks = &max_blocks_out;
} else {
cc = &receive_context;
encrypt = CIPHER_DECRYPT;
+ p_read.packets = p_read.blocks = 0;
+ max_blocks = &max_blocks_in;
}
if (newkeys[mode] != NULL) {
debug("set_newkeys: rekeying");
@@ -610,13 +635,16 @@
buffer_compress_init_recv();
comp->enabled = 1;
}
+ *max_blocks = ((u_int64_t)1 << (enc->block_size*2));
+ if (rekey_limit)
+ *max_blocks = MIN(*max_blocks, rekey_limit / enc->block_size);
}
/*
* Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
*/
static void
-packet_send2(void)
+packet_send2_wrapped(void)
{
u_char type, *cp, *macbuf = NULL;
u_char padlen, pad;
@@ -698,10 +726,10 @@
/* compute MAC over seqnr and packet(length fields, payload, padding) */
if (mac && mac->enabled) {
- macbuf = mac_compute(mac, send_seqnr,
+ macbuf = mac_compute(mac, p_send.seqnr,
buffer_ptr(&outgoing_packet),
buffer_len(&outgoing_packet));
- DBG(debug("done calc MAC out #%d", send_seqnr));
+ DBG(debug("done calc MAC out #%d", p_send.seqnr));
}
/* encrypt packet and append to output buffer. */
cp = buffer_append_space(&output, buffer_len(&outgoing_packet));
@@ -715,14 +743,64 @@
buffer_dump(&output);
#endif
/* increment sequence number for outgoing packets */
- if (++send_seqnr == 0)
+ if (++p_send.seqnr == 0)
log("outgoing seqnr wraps around");
+ if (++p_send.packets == 0)
+ if (!(datafellows & SSH_BUG_NOREKEY))
+ fatal("XXX too many packets with same key");
+ p_send.blocks += (packet_length + 4) / block_size;
buffer_clear(&outgoing_packet);
if (type == SSH2_MSG_NEWKEYS)
set_newkeys(MODE_OUT);
}
+static void
+packet_send2(void)
+{
+ static int rekeying = 0;
+ struct packet *p;
+ u_char type, *cp;
+
+ cp = buffer_ptr(&outgoing_packet);
+ type = cp[5];
+
+ /* during rekeying we can only send key exchange messages */
+ if (rekeying) {
+ if (!((type >= SSH2_MSG_TRANSPORT_MIN) &&
+ (type <= SSH2_MSG_TRANSPORT_MAX))) {
+ debug("enqueue packet: %u", type);
+ p = xmalloc(sizeof(*p));
+ p->type = type;
+ memcpy(&p->payload, &outgoing_packet, sizeof(Buffer));
+ buffer_init(&outgoing_packet);
+ TAILQ_INSERT_TAIL(&outgoing, p, next);
+ return;
+ }
+ }
+
+ /* rekeying starts with sending KEXINIT */
+ if (type == SSH2_MSG_KEXINIT)
+ rekeying = 1;
+
+ packet_send2_wrapped();
+
+ /* after a NEWKEYS message we can send the complete queue */
+ if (type == SSH2_MSG_NEWKEYS) {
+ rekeying = 0;
+ while ((p = TAILQ_FIRST(&outgoing))) {
+ type = p->type;
+ debug("dequeue packet: %u", type);
+ buffer_free(&outgoing_packet);
+ memcpy(&outgoing_packet, &p->payload,
+ sizeof(Buffer));
+ TAILQ_REMOVE(&outgoing, p, next);
+ xfree(p);
+ packet_send2_wrapped();
+ }
+ }
+}
+
void
packet_send(void)
{
@@ -966,18 +1044,22 @@
* increment sequence number for incoming packet
*/
if (mac && mac->enabled) {
- macbuf = mac_compute(mac, read_seqnr,
+ macbuf = mac_compute(mac, p_read.seqnr,
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", read_seqnr));
+ DBG(debug("MAC #%d ok", p_read.seqnr));
buffer_consume(&input, mac->mac_len);
}
if (seqnr_p != NULL)
- *seqnr_p = read_seqnr;
- if (++read_seqnr == 0)
+ *seqnr_p = p_read.seqnr;
+ if (++p_read.seqnr == 0)
log("incoming seqnr wraps around");
+ if (++p_read.packets == 0)
+ if (!(datafellows & SSH_BUG_NOREKEY))
+ fatal("XXX too many packets with same key");
+ p_read.blocks += (packet_length + 4) / block_size;
/* get padlen */
cp = buffer_ptr(&incoming_packet);
@@ -1416,3 +1498,22 @@
rand >>= 8;
}
}
+
+#define MAX_PACKETS (1<<31)
+int
+packet_need_rekeying(void)
+{
+ if (datafellows & SSH_BUG_NOREKEY)
+ return 0;
+ return
+ (p_send.packets > MAX_PACKETS) ||
+ (p_read.packets > MAX_PACKETS) ||
+ (max_blocks_out && (p_send.blocks > max_blocks_out)) ||
+ (max_blocks_in && (p_read.blocks > max_blocks_in));
+}
+
+void
+packet_set_rekey_limit(u_int32_t bytes)
+{
+ rekey_limit = bytes;
+}
diff --git a/packet.h b/packet.h
index 46830c3..82ed7c7 100644
--- a/packet.h
+++ b/packet.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: packet.h,v 1.37 2003/04/01 10:22:21 markus Exp $ */
+/* $OpenBSD: packet.h,v 1.38 2003/04/02 09:48:07 markus Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -62,8 +62,8 @@
void packet_get_keyiv(int, u_char *, u_int);
int packet_get_keycontext(int, u_char *);
void packet_set_keycontext(int, u_char *);
-u_int32_t packet_get_seqnr(int);
-void packet_set_seqnr(int, u_int32_t);
+void packet_get_state(int, u_int32_t *, u_int64_t *, u_int32_t *);
+void packet_set_state(int, u_int32_t, u_int64_t, u_int32_t);
int packet_get_ssh1_cipher(void);
void packet_set_iv(int, u_char *);
@@ -96,4 +96,7 @@
} \
} while (0)
+int packet_need_rekeying(void);
+void packet_set_rekey_limit(u_int32_t);
+
#endif /* PACKET_H */
diff --git a/readconf.c b/readconf.c
index 1df5ce2..a104270 100644
--- a/readconf.c
+++ b/readconf.c
@@ -12,7 +12,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: readconf.c,v 1.104 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: readconf.c,v 1.105 2003/04/02 09:48:07 markus Exp $");
#include "ssh.h"
#include "xmalloc.h"
@@ -114,7 +114,7 @@
oDynamicForward, oPreferredAuthentications, oHostbasedAuthentication,
oHostKeyAlgorithms, oBindAddress, oSmartcardDevice,
oClearAllForwardings, oNoHostAuthenticationForLocalhost,
- oEnableSSHKeysign,
+ oEnableSSHKeysign, oRekeyLimit,
oDeprecated
} OpCodes;
@@ -188,6 +188,7 @@
{ "clearallforwardings", oClearAllForwardings },
{ "enablesshkeysign", oEnableSSHKeysign },
{ "nohostauthenticationforlocalhost", oNoHostAuthenticationForLocalhost },
+ { "rekeylimit", oRekeyLimit },
{ NULL, oBadOption }
};
@@ -423,6 +424,31 @@
intptr = &options->compression_level;
goto parse_int;
+ case oRekeyLimit:
+ intptr = &options->rekey_limit;
+ arg = strdelim(&s);
+ if (!arg || *arg == '\0')
+ fatal("%.200s line %d: Missing argument.", filename, linenum);
+ if (arg[0] < '0' || arg[0] > '9')
+ fatal("%.200s line %d: Bad number.", filename, linenum);
+ value = strtol(arg, &endofnumber, 10);
+ if (arg == endofnumber)
+ fatal("%.200s line %d: Bad number.", filename, linenum);
+ switch (toupper(*endofnumber)) {
+ case 'K':
+ value *= 1<<10;
+ break;
+ case 'M':
+ value *= 1<<20;
+ break;
+ case 'G':
+ value *= 1<<30;
+ break;
+ }
+ if (*activep && *intptr == -1)
+ *intptr = value;
+ break;
+
case oIdentityFile:
arg = strdelim(&s);
if (!arg || *arg == '\0')
@@ -795,6 +821,7 @@
options->smartcard_device = NULL;
options->enable_ssh_keysign = - 1;
options->no_host_authentication_for_localhost = - 1;
+ options->rekey_limit = - 1;
}
/*
@@ -911,6 +938,8 @@
options->no_host_authentication_for_localhost = 0;
if (options->enable_ssh_keysign == -1)
options->enable_ssh_keysign = 0;
+ if (options->rekey_limit == -1)
+ options->rekey_limit = 0;
/* options->proxy_command should not be set by default */
/* options->user will be set in the main program if appropriate */
/* options->hostname will be set in the main program if appropriate */
diff --git a/readconf.h b/readconf.h
index 78e04fe..d354721 100644
--- a/readconf.h
+++ b/readconf.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: readconf.h,v 1.46 2003/04/01 10:22:21 markus Exp $ */
+/* $OpenBSD: readconf.h,v 1.47 2003/04/02 09:48:07 markus Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -101,6 +101,7 @@
int clear_forwardings;
int enable_ssh_keysign;
+ int rekey_limit;
int no_host_authentication_for_localhost;
} Options;
diff --git a/serverloop.c b/serverloop.c
index f4df9cc..187afc7 100644
--- a/serverloop.c
+++ b/serverloop.c
@@ -35,7 +35,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: serverloop.c,v 1.106 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: serverloop.c,v 1.107 2003/04/02 09:48:07 markus Exp $");
#include "xmalloc.h"
#include "packet.h"
@@ -771,8 +771,14 @@
&nalloc, 0);
collect_children();
- if (!rekeying)
+ if (!rekeying) {
channel_after_select(readset, writeset);
+ if (packet_need_rekeying()) {
+ debug("need rekeying");
+ xxx_kex->done = 0;
+ kex_send_kexinit(xxx_kex);
+ }
+ }
process_input(readset);
if (connection_closed)
break;
diff --git a/sshconnect2.c b/sshconnect2.c
index 642b34b..41768bf 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -23,7 +23,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.114 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: sshconnect2.c,v 1.115 2003/04/02 09:48:07 markus Exp $");
#include "ssh.h"
#include "ssh2.h"
@@ -108,6 +108,9 @@
myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
options.hostkeyalgorithms;
+ if (options.rekey_limit)
+ packet_set_rekey_limit(options.rekey_limit);
+
/* start key exchange */
kex = kex_setup(myproposal);
kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;