- (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@

10 files changed, 205 insertions, 42 deletions

diff --git a/ChangeLog b/ChangeLog
index afc34a291..140a176f2 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 af207c070..a40019d08 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 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
                 /* 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 bcd007e60..4cd10a108 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 @@ mm_get_keystate(struct monitor *pmonitor)
         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 @@ mm_get_keystate(struct monitor *pmonitor)
         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 c9714138a..f674ef78d 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 @@ mm_send_keystate(struct monitor *pmonitor)
         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 @@ mm_send_keystate(struct monitor *pmonitor)
         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 254e452d0..9887d25af 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 @@ static int interactive_mode = 0;
 
 /* 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 @@ static u_int ssh1_keylen;
 /* 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 @@ packet_set_connection(int fd_in, int fd_out)
                 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 @@ packet_get_ssh1_cipher()
         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 @@ set_newkeys(int mode)
         Mac *mac;
         Comp *comp;
         CipherContext *cc;
+        u_int64_t *max_blocks;
         int encrypt;
 
         debug2("set_newkeys: mode %d", mode);
@@ -569,9 +590,13 @@ set_newkeys(int mode)
         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 @@ set_newkeys(int mode)
                         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 @@ packet_send2(void)
 
         /* 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 @@ packet_send2(void)
         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 @@ packet_read_poll2(u_int32_t *seqnr_p)
          * 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 @@ packet_send_ignore(int nbytes)
                 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 46830c3df..82ed7c747 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 @@ int	 packet_get_keyiv_len(int);
 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 @@ do { \
         } \
 } 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 1df5ce2d9..a10427086 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 @@ typedef enum {
         oDynamicForward, oPreferredAuthentications, oHostbasedAuthentication,
         oHostKeyAlgorithms, oBindAddress, oSmartcardDevice,
         oClearAllForwardings, oNoHostAuthenticationForLocalhost,
-        oEnableSSHKeysign,
+        oEnableSSHKeysign, oRekeyLimit,
         oDeprecated
 } OpCodes;
 
@@ -188,6 +188,7 @@ static struct {
         { "clearallforwardings", oClearAllForwardings },
         { "enablesshkeysign", oEnableSSHKeysign },
         { "nohostauthenticationforlocalhost", oNoHostAuthenticationForLocalhost },
+        { "rekeylimit", oRekeyLimit },
         { NULL, oBadOption }
 };
 
@@ -423,6 +424,31 @@ parse_flag:
                 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 @@ initialize_options(Options * options)
         options->smartcard_device = NULL;
         options->enable_ssh_keysign = - 1;
         options->no_host_authentication_for_localhost = - 1;
+        options->rekey_limit = - 1;
 }
 
 /*
@@ -911,6 +938,8 @@ fill_default_options(Options * options)
                 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 78e04fedf..d35472117 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 @@ typedef struct {
         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 f4df9cccb..187afc716 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 @@ server_loop2(Authctxt *authctxt)
                     &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 642b34b9e..41768bf05 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 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
                 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;