X-Git-Url: http://andersk.mit.edu/gitweb/gssapi-openssh.git/blobdiff_plain/96c41595f1ca0665084d7f54ae6d13e0ad270d03..436bf0dada8139f94ab4537fcefd421b52a86564:/openssh/packet.c diff --git a/openssh/packet.c b/openssh/packet.c index c298013..36656ba 100644 --- a/openssh/packet.c +++ b/openssh/packet.c @@ -1,3 +1,4 @@ +/* $OpenBSD: packet.c,v 1.148 2007/06/07 19:37:34 pvalchev Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -37,29 +38,45 @@ */ #include "includes.h" -RCSID("$OpenBSD: packet.c,v 1.93 2002/03/24 16:01:13 markus Exp $"); + +#include +#include "openbsd-compat/sys-queue.h" +#include +#include +#ifdef HAVE_SYS_TIME_H +# include +#endif + +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include #include "xmalloc.h" #include "buffer.h" #include "packet.h" -#include "bufaux.h" #include "crc32.h" -#include "getput.h" - #include "compress.h" #include "deattack.h" #include "channels.h" - #include "compat.h" #include "ssh1.h" #include "ssh2.h" - #include "cipher.h" +#include "key.h" #include "kex.h" #include "mac.h" #include "log.h" #include "canohost.h" #include "misc.h" +#include "ssh.h" #ifdef PACKET_DEBUG #define DBG(x) x @@ -105,7 +122,7 @@ static int compression_buffer_ready = 0; static int packet_compression = 0; /* default maximum packet size */ -int max_packet_size = 32768; +u_int max_packet_size = 32768; /* Flag indicating whether this module has been initialized. */ static int initialized = 0; @@ -113,14 +130,37 @@ static int initialized = 0; /* 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 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]; +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. @@ -129,12 +169,15 @@ void packet_set_connection(int fd_in, int fd_out) { Cipher *none = cipher_by_name("none"); + if (none == NULL) fatal("packet_set_connection: cannot load cipher 'none'"); connection_in = fd_in; connection_out = fd_out; - cipher_init(&send_context, none, "", 0, NULL, 0, CIPHER_ENCRYPT); - cipher_init(&receive_context, none, "", 0, NULL, 0, CIPHER_DECRYPT); + cipher_init(&send_context, none, (const u_char *)"", + 0, NULL, 0, CIPHER_ENCRYPT); + cipher_init(&receive_context, none, (const u_char *)"", + 0, NULL, 0, CIPHER_DECRYPT); newkeys[MODE_IN] = newkeys[MODE_OUT] = NULL; if (!initialized) { initialized = 1; @@ -142,9 +185,8 @@ 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); } /* Returns 1 if remote host is connected via socket, 0 if not. */ @@ -230,6 +272,7 @@ packet_get_keyiv_len(int mode) return (cipher_get_keyiv_len(cc)); } + void packet_set_iv(int mode, u_char *dat) { @@ -242,28 +285,33 @@ packet_set_iv(int mode, u_char *dat) cipher_set_keyiv(cc, dat); } + int -packet_get_ssh1_cipher() +packet_get_ssh1_cipher(void) { 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("%s: bad mode %d", __FUNCTION__, 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 */ @@ -280,7 +328,7 @@ packet_connection_is_ipv4(void) if (to.ss_family == AF_INET) return 1; #ifdef IPV4_IN_IPV6 - if (to.ss_family == AF_INET6 && + if (to.ss_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr)) return 1; #endif @@ -293,13 +341,10 @@ void packet_set_nonblocking(void) { /* Set the socket into non-blocking mode. */ - if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0) - error("fcntl O_NONBLOCK: %.100s", strerror(errno)); + set_nonblock(connection_in); - if (connection_out != connection_in) { - if (fcntl(connection_out, F_SETFL, O_NONBLOCK) < 0) - error("fcntl O_NONBLOCK: %.100s", strerror(errno)); - } + if (connection_out != connection_in) + set_nonblock(connection_out); } /* Returns the socket used for reading. */ @@ -391,19 +436,34 @@ packet_start_compression(int level) * key is used for both sending and reception. However, both directions are * encrypted independently of each other. */ + void packet_set_encryption_key(const u_char *key, u_int keylen, int number) { Cipher *cipher = cipher_by_number(number); + if (cipher == NULL) fatal("packet_set_encryption_key: unknown cipher number %d", number); if (keylen < 20) fatal("packet_set_encryption_key: keylen too small: %d", keylen); + if (keylen > SSH_SESSION_KEY_LENGTH) + fatal("packet_set_encryption_key: keylen too big: %d", keylen); + memcpy(ssh1_key, key, keylen); + ssh1_keylen = keylen; cipher_init(&send_context, cipher, key, keylen, NULL, 0, CIPHER_ENCRYPT); cipher_init(&receive_context, cipher, key, keylen, NULL, 0, CIPHER_DECRYPT); } +u_int +packet_get_encryption_key(u_char *key) +{ + if (key == NULL) + return (ssh1_keylen); + memcpy(key, ssh1_key, ssh1_keylen); + return (ssh1_keylen); +} + /* Start constructing a packet to send. */ void packet_start(u_char type) @@ -424,33 +484,40 @@ void packet_put_char(int value) { char ch = value; + buffer_append(&outgoing_packet, &ch, 1); } + void packet_put_int(u_int value) { buffer_put_int(&outgoing_packet, value); } + void packet_put_string(const void *buf, u_int len) { buffer_put_string(&outgoing_packet, buf, len); } + void packet_put_cstring(const char *str) { buffer_put_cstring(&outgoing_packet, str); } + void packet_put_raw(const void *buf, u_int len) { buffer_append(&outgoing_packet, buf, len); } + void packet_put_bignum(BIGNUM * value) { buffer_put_bignum(&outgoing_packet, value); } + void packet_put_bignum2(BIGNUM * value) { @@ -468,7 +535,7 @@ packet_send1(void) 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 @@ -494,9 +561,9 @@ packet_send1(void) 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); @@ -504,7 +571,7 @@ packet_send1(void) /* Add check bytes. */ checksum = ssh_crc32(buffer_ptr(&outgoing_packet), buffer_len(&outgoing_packet)); - PUT_32BIT(buf, checksum); + put_u32(buf, checksum); buffer_append(&outgoing_packet, buf, 4); #ifdef PACKET_DEBUG @@ -513,7 +580,7 @@ packet_send1(void) #endif /* Append to output. */ - PUT_32BIT(buf, len); + put_u32(buf, len); buffer_append(&output, buf, 4); cp = buffer_append_space(&output, buffer_len(&outgoing_packet)); cipher_crypt(&send_context, cp, buffer_ptr(&outgoing_packet), @@ -527,7 +594,7 @@ packet_send1(void) 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. */ @@ -540,24 +607,29 @@ set_newkeys(int mode) Mac *mac; Comp *comp; CipherContext *cc; - int encrypt; + u_int64_t *max_blocks; + int crypt_type; - debug("newkeys: mode %d", mode); + 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; } if (newkeys[mode] != NULL) { - debug("newkeys: rekeying"); + debug("set_newkeys: rekeying"); cipher_cleanup(cc); enc = &newkeys[mode]->enc; mac = &newkeys[mode]->mac; comp = &newkeys[mode]->comp; - memset(mac->key, 0, mac->key_len); + mac_clear(mac); xfree(enc->name); xfree(enc->iv); xfree(enc->key); @@ -572,15 +644,18 @@ set_newkeys(int mode) enc = &newkeys[mode]->enc; mac = &newkeys[mode]->mac; comp = &newkeys[mode]->comp; - if (mac->md != NULL) + if (mac_init(mac) == 0) 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) { + memset(enc->key, 0, enc->key_len); + memset(mac->key, 0, mac->key_len); */ + 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); @@ -588,19 +663,61 @@ set_newkeys(int mode) buffer_compress_init_recv(); comp->enabled = 1; } + /* + * The 2^(blocksize*2) limit is too expensive for 3DES, + * blowfish, etc, so enforce a 1GB limit for small blocksizes. + */ + if (enc->block_size >= 16) + *max_blocks = (u_int64_t)1 << (enc->block_size*2); + else + *max_blocks = ((u_int64_t)1 << 30) / enc->block_size; + if (rekey_limit) + *max_blocks = MIN(*max_blocks, rekey_limit / enc->block_size); +} + +/* + * Delayed compression for SSH2 is enabled after authentication: + * This happens 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++) { + /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */ + if (newkeys[mode] == NULL) + continue; + 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) */ static void -packet_send2(void) +packet_send2_wrapped(void) { u_char type, *cp, *macbuf = NULL; 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; @@ -659,9 +776,9 @@ packet_send2(void) /* 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 */ @@ -670,16 +787,16 @@ packet_send2(void) /* packet_length includes payload, padding and padding length field */ packet_length = buffer_len(&outgoing_packet) - 4; cp = buffer_ptr(&outgoing_packet); - PUT_32BIT(cp, packet_length); + put_u32(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, 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)); @@ -687,18 +804,70 @@ packet_send2(void) buffer_len(&outgoing_packet)); /* append unencrypted MAC */ if (mac && mac->enabled) - buffer_append(&output, (char *)macbuf, mac->mac_len); + buffer_append(&output, macbuf, mac->mac_len); #ifdef PACKET_DEBUG fprintf(stderr, "encrypted: "); buffer_dump(&output); #endif /* increment sequence number for outgoing packets */ - if (++send_seqnr == 0) - log("outgoing seqnr wraps around"); + if (++p_send.seqnr == 0) + logit("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); + else if (type == SSH2_MSG_USERAUTH_SUCCESS && server_side) + packet_enable_delayed_compress(); +} + +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 @@ -725,7 +894,7 @@ packet_read_seqnr(u_int32_t *seqnr_p) char buf[8192]; DBG(debug("packet_read()")); - setp = (fd_set *)xmalloc(howmany(connection_in+1, NFDBITS) * + setp = (fd_set *)xcalloc(howmany(connection_in+1, NFDBITS), sizeof(fd_mask)); /* Since we are blocking, ensure that all written packets have been sent. */ @@ -762,8 +931,8 @@ packet_read_seqnr(u_int32_t *seqnr_p) /* Read data from the socket. */ len = read(connection_in, buf, sizeof(buf)); if (len == 0) { - log("Connection closed by %.200s", get_remote_ipaddr()); - fatal_cleanup(); + logit("Connection closed by %.200s", get_remote_ipaddr()); + cleanup_exit(255); } if (len < 0) fatal("Read from socket failed: %.100s", strerror(errno)); @@ -816,9 +985,9 @@ packet_read_poll1(void) return SSH_MSG_NONE; /* Get length of incoming packet. */ cp = buffer_ptr(&input); - len = GET_32BIT(cp); + len = get_u32(cp); if (len < 1 + 2 + 2 || len > 256 * 1024) - packet_disconnect("Bad packet length %d.", len); + packet_disconnect("Bad packet length %u.", len); padded_len = (len + 8) & ~7; /* Check if the packet has been entirely received. */ @@ -835,9 +1004,16 @@ packet_read_poll1(void) * (C)1998 CORE-SDI, Buenos Aires Argentina * Ariel Futoransky(futo@core-sdi.com) */ - if (!receive_context.plaintext && - detect_attack(buffer_ptr(&input), padded_len, NULL) == DEATTACK_DETECTED) - packet_disconnect("crc32 compensation attack: network attack detected"); + if (!receive_context.plaintext) { + switch (detect_attack(buffer_ptr(&input), padded_len)) { + case DEATTACK_DETECTED: + packet_disconnect("crc32 compensation attack: " + "network attack detected"); + case DEATTACK_DOS_DETECTED: + packet_disconnect("deattack denial of " + "service detected"); + } + } /* Decrypt data to incoming_packet. */ buffer_clear(&incoming_packet); @@ -864,7 +1040,7 @@ packet_read_poll1(void) len, buffer_len(&incoming_packet)); cp = (u_char *)buffer_ptr(&incoming_packet) + len - 4; - stored_checksum = GET_32BIT(cp); + stored_checksum = get_u32(cp); if (checksum != stored_checksum) packet_disconnect("Corrupted check bytes on input."); buffer_consume_end(&incoming_packet, 4); @@ -877,6 +1053,8 @@ packet_read_poll1(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; } @@ -886,7 +1064,7 @@ packet_read_poll2(u_int32_t *seqnr_p) 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; @@ -911,12 +1089,14 @@ packet_read_poll2(u_int32_t *seqnr_p) cipher_crypt(&receive_context, cp, buffer_ptr(&input), block_size); cp = buffer_ptr(&incoming_packet); - packet_length = GET_32BIT(cp); + packet_length = get_u32(cp); if (packet_length < 1 + 4 || packet_length > 256 * 1024) { +#ifdef PACKET_DEBUG buffer_dump(&incoming_packet); - packet_disconnect("Bad packet length %d.", packet_length); +#endif + packet_disconnect("Bad packet length %u.", packet_length); } - DBG(debug("input: packet len %d", packet_length+4)); + DBG(debug("input: packet len %u", packet_length+4)); buffer_consume(&input, block_size); } /* we have a partial packet of block_size bytes */ @@ -944,18 +1124,22 @@ 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) - log("incoming seqnr wraps around"); + *seqnr_p = p_read.seqnr; + if (++p_read.seqnr == 0) + logit("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); @@ -975,15 +1159,20 @@ packet_read_poll2(u_int32_t *seqnr_p) buffer_clear(&incoming_packet); buffer_append(&incoming_packet, buffer_ptr(&compression_buffer), buffer_len(&compression_buffer)); - DBG(debug("input: len after de-compress %d", buffer_len(&incoming_packet))); + DBG(debug("input: len after de-compress %d", + buffer_len(&incoming_packet))); } /* * get packet type, implies consume. * 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); @@ -996,7 +1185,7 @@ packet_read_poll2(u_int32_t *seqnr_p) int packet_read_poll_seqnr(u_int32_t *seqnr_p) { - int reason, seqnr; + u_int reason, seqnr; u_char type; char *msg; @@ -1019,18 +1208,18 @@ packet_read_poll_seqnr(u_int32_t *seqnr_p) case SSH2_MSG_DISCONNECT: reason = packet_get_int(); msg = packet_get_string(NULL); - log("Received disconnect from %s: %d: %.400s", get_remote_ipaddr(), - reason, msg); + logit("Received disconnect from %s: %u: %.400s", + get_remote_ipaddr(), reason, msg); xfree(msg); - fatal_cleanup(); + cleanup_exit(255); break; case SSH2_MSG_UNIMPLEMENTED: seqnr = packet_get_int(); - debug("Received SSH2_MSG_UNIMPLEMENTED for %d", seqnr); + debug("Received SSH2_MSG_UNIMPLEMENTED for %u", + seqnr); break; default: return type; - break; } } else { type = packet_read_poll1(); @@ -1044,16 +1233,14 @@ packet_read_poll_seqnr(u_int32_t *seqnr_p) break; case SSH_MSG_DISCONNECT: msg = packet_get_string(NULL); - log("Received disconnect from %s: %.400s", get_remote_ipaddr(), - msg); - fatal_cleanup(); - xfree(msg); + logit("Received disconnect from %s: %.400s", + get_remote_ipaddr(), msg); + cleanup_exit(255); break; default: if (type) DBG(debug("received packet type %d", type)); return type; - break; } } } @@ -1082,6 +1269,7 @@ u_int packet_get_char(void) { char ch; + buffer_get(&incoming_packet, &ch, 1); return (u_char) ch; } @@ -1112,9 +1300,10 @@ packet_get_bignum2(BIGNUM * value) } 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; return buffer_ptr(&incoming_packet); @@ -1139,13 +1328,6 @@ 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 @@ -1194,6 +1376,7 @@ packet_disconnect(const char *fmt,...) char buf[1024]; va_list args; static int disconnecting = 0; + if (disconnecting) /* Guard against recursive invocations. */ fatal("packet_disconnect called recursively."); disconnecting = 1; @@ -1206,6 +1389,9 @@ packet_disconnect(const char *fmt,...) vsnprintf(buf, sizeof(buf), fmt, args); va_end(args); + /* Display the error locally */ + logit("Disconnecting: %.100s", buf); + /* Send the disconnect message to the other side, and wait for it to get sent. */ if (compat20) { packet_start(SSH2_MSG_DISCONNECT); @@ -1224,10 +1410,7 @@ packet_disconnect(const char *fmt,...) /* Close the connection. */ packet_close(); - - /* Display the error locally and exit. */ - log("Disconnecting: %.100s", buf); - fatal_cleanup(); + cleanup_exit(255); } /* Checks if there is any buffered output, and tries to write some of the output. */ @@ -1236,6 +1419,7 @@ void packet_write_poll(void) { int len = buffer_len(&output); + if (len > 0) { len = write(connection_out, buffer_ptr(&output), len); if (len <= 0) { @@ -1258,7 +1442,7 @@ packet_write_wait(void) { fd_set *setp; - setp = (fd_set *)xmalloc(howmany(connection_out + 1, NFDBITS) * + setp = (fd_set *)xcalloc(howmany(connection_out + 1, NFDBITS), sizeof(fd_mask)); packet_write_poll(); while (packet_have_data_to_write()) { @@ -1292,16 +1476,29 @@ packet_not_very_much_data_to_write(void) return buffer_len(&output) < 128 * 1024; } + +static void +packet_set_tos(int interactive) +{ +#if defined(IP_TOS) && !defined(IP_TOS_IS_BROKEN) + int tos = interactive ? IPTOS_LOWDELAY : IPTOS_THROUGHPUT; + + if (!packet_connection_is_on_socket() || + !packet_connection_is_ipv4()) + return; + if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, &tos, + sizeof(tos)) < 0) + error("setsockopt IP_TOS %d: %.100s:", + tos, strerror(errno)); +#endif +} + /* Informs that the current session is interactive. Sets IP flags for that. */ void packet_set_interactive(int interactive) { static int called = 0; -#if defined(IP_TOS) && !defined(IP_TOS_IS_BROKEN) - int lowdelay = IPTOS_LOWDELAY; - int throughput = IPTOS_THROUGHPUT; -#endif if (called) return; @@ -1313,34 +1510,8 @@ packet_set_interactive(int interactive) /* Only set socket options if using a socket. */ if (!packet_connection_is_on_socket()) return; - /* - * IPTOS_LOWDELAY and IPTOS_THROUGHPUT are IPv4 only - */ - if (interactive) { - /* - * Set IP options for an interactive connection. Use - * IPTOS_LOWDELAY and TCP_NODELAY. - */ -#if defined(IP_TOS) && !defined(IP_TOS_IS_BROKEN) - if (packet_connection_is_ipv4()) { - if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, - &lowdelay, sizeof(lowdelay)) < 0) - error("setsockopt IPTOS_LOWDELAY: %.100s", - strerror(errno)); - } -#endif - 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, &throughput, - sizeof(throughput)) < 0) - error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno)); -#endif - } + set_nodelay(connection_in); + packet_set_tos(interactive); } /* Returns true if the current connection is interactive. */ @@ -1352,16 +1523,17 @@ packet_is_interactive(void) } int -packet_set_maxsize(int s) +packet_set_maxsize(u_int s) { static int called = 0; + if (called) { - log("packet_set_maxsize: called twice: old %d new %d", + logit("packet_set_maxsize: called twice: old %d new %d", max_packet_size, s); return -1; } if (s < 4 * 1024 || s > 1024 * 1024) { - log("packet_set_maxsize: bad size %d", s); + logit("packet_set_maxsize: bad size %d", s); return -1; } called = 1; @@ -1391,15 +1563,58 @@ packet_add_padding(u_char pad) 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((u_char)rnd & 0xff); + rnd >>= 8; + } +} +int rekey_requested = 0; + +void +packet_request_rekeying(void) +{ + rekey_requested = 1; +} + +#define MAX_PACKETS (1U<<31) +int +packet_need_rekeying(void) +{ + if (datafellows & SSH_BUG_NOREKEY) + return 0; + if (rekey_requested == 1) + { + rekey_requested = 0; + return 1; } + 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; +} + +void +packet_set_server(void) +{ + server_side = 1; +} + +void +packet_set_authenticated(void) +{ + after_authentication = 1; }