From ffd7b36ba59c788a8f61907d042a41531656233a Mon Sep 17 00:00:00 2001 From: djm Date: Wed, 9 Apr 2003 10:50:06 +0000 Subject: [PATCH] - (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@ --- ChangeLog | 5 ++ clientloop.c | 7 +-- monitor.c | 14 ++++- monitor_wrap.c | 14 ++++- packet.c | 145 +++++++++++++++++++++++++++++++++++++++++-------- packet.h | 9 ++- readconf.c | 33 ++++++++++- readconf.h | 3 +- serverloop.c | 10 +++- sshconnect2.c | 5 +- 10 files changed, 204 insertions(+), 41 deletions(-) diff --git a/ChangeLog b/ChangeLog index 2665f03d..c395ef14 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 diff --git a/clientloop.c b/clientloop.c index af207c07..a40019d0 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 $"); #include "ssh.h" #include "ssh1.h" @@ -968,9 +968,8 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id) /* Do channel operations unless rekeying in progress. */ if (!rekeying) { channel_after_select(readset, writeset); - - if (need_rekeying) { - debug("user requests rekeying"); + if (need_rekeying || packet_need_rekeying()) { + debug("need rekeying"); xxx_kex->done = 0; kex_send_kexinit(xxx_kex); need_rekeying = 0; diff --git a/monitor.c b/monitor.c index bcd007e6..4cd10a10 100644 --- a/monitor.c +++ b/monitor.c @@ -25,7 +25,7 @@ */ #include "includes.h" -RCSID("$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 $"); #include @@ -1497,6 +1497,8 @@ mm_get_keystate(struct monitor *pmonitor) Buffer m; u_char *blob, *p; u_int bloblen, plen; + u_int32_t seqnr, packets; + u_int64_t blocks; debug3("%s: Waiting for new keys", __func__); @@ -1526,8 +1528,14 @@ mm_get_keystate(struct monitor *pmonitor) xfree(blob); /* Now get sequence numbers for the packets */ - packet_set_seqnr(MODE_OUT, buffer_get_int(&m)); - packet_set_seqnr(MODE_IN, buffer_get_int(&m)); + seqnr = buffer_get_int(&m); + blocks = buffer_get_int64(&m); + packets = buffer_get_int(&m); + packet_set_state(MODE_OUT, seqnr, blocks, packets); + seqnr = buffer_get_int(&m); + blocks = buffer_get_int64(&m); + packets = buffer_get_int(&m); + packet_set_state(MODE_IN, seqnr, blocks, packets); skip: /* Get the key context */ diff --git a/monitor_wrap.c b/monitor_wrap.c index c9714138..f674ef78 100644 --- a/monitor_wrap.c +++ b/monitor_wrap.c @@ -25,7 +25,7 @@ */ #include "includes.h" -RCSID("$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 $"); #include #include @@ -520,6 +520,8 @@ mm_send_keystate(struct monitor *pmonitor) Buffer m; u_char *blob, *p; u_int bloblen, plen; + u_int32_t seqnr, packets; + u_int64_t blocks; buffer_init(&m); @@ -568,8 +570,14 @@ mm_send_keystate(struct monitor *pmonitor) buffer_put_string(&m, blob, bloblen); xfree(blob); - buffer_put_int(&m, packet_get_seqnr(MODE_OUT)); - buffer_put_int(&m, packet_get_seqnr(MODE_IN)); + packet_get_state(MODE_OUT, &seqnr, &blocks, &packets); + buffer_put_int(&m, seqnr); + buffer_put_int64(&m, blocks); + buffer_put_int(&m, packets); + packet_get_state(MODE_OUT, &seqnr, &blocks, &packets); + buffer_put_int(&m, seqnr); + buffer_put_int64(&m, blocks); + buffer_put_int(&m, packets); debug3("%s: New keys have been sent", __func__); skip: diff --git a/packet.c b/packet.c index 254e452d..9887d25a 100644 --- a/packet.c +++ b/packet.c @@ -37,7 +37,9 @@ */ #include "includes.h" -RCSID("$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 #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 46830c3d..82ed7c74 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 @@ -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 1df5ce2d..a1042708 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 78e04fed..d3547211 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 @@ -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 f4df9ccc..187afc71 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 $"); #include "xmalloc.h" #include "packet.h" @@ -771,8 +771,14 @@ server_loop2(Authctxt *authctxt) &nalloc, 0); collect_children(); - if (!rekeying) + if (!rekeying) { channel_after_select(readset, writeset); + if (packet_need_rekeying()) { + debug("need rekeying"); + xxx_kex->done = 0; + kex_send_kexinit(xxx_kex); + } + } process_input(readset); if (connection_closed) break; diff --git a/sshconnect2.c b/sshconnect2.c index 642b34b9..41768bf0 100644 --- a/sshconnect2.c +++ b/sshconnect2.c @@ -23,7 +23,7 @@ */ #include "includes.h" -RCSID("$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; -- 2.45.1