diff options
Diffstat (limited to 'crypto/openssh/packet.c')
| -rw-r--r-- | crypto/openssh/packet.c | 459 |
1 files changed, 184 insertions, 275 deletions
diff --git a/crypto/openssh/packet.c b/crypto/openssh/packet.c index 00109ea..b3e6d84 100644 --- a/crypto/openssh/packet.c +++ b/crypto/openssh/packet.c @@ -13,7 +13,7 @@ * * * SSH2 packet format added by Markus Friedl. - * Copyright (c) 2000 Markus Friedl. All rights reserved. + * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -37,7 +37,7 @@ */ #include "includes.h" -RCSID("$OpenBSD: packet.c,v 1.61 2001/04/05 10:42:51 markus Exp $"); +RCSID("$OpenBSD: packet.c,v 1.90 2002/02/27 21:23:13 stevesk Exp $"); #include "xmalloc.h" #include "buffer.h" @@ -59,6 +59,7 @@ RCSID("$OpenBSD: packet.c,v 1.61 2001/04/05 10:42:51 markus Exp $"); #include "mac.h" #include "log.h" #include "canohost.h" +#include "misc.h" #ifdef PACKET_DEBUG #define DBG(x) x @@ -75,12 +76,6 @@ RCSID("$OpenBSD: packet.c,v 1.61 2001/04/05 10:42:51 markus Exp $"); static int connection_in = -1; static int connection_out = -1; -/* - * Cipher type. This value is only used to determine whether to pad the - * packets with zeroes or random data. - */ -static int cipher_type = SSH_CIPHER_NONE; - /* Protocol flags for the remote side. */ static u_int remote_protocol_flags = 0; @@ -118,19 +113,11 @@ static int initialized = 0; /* Set to true if the connection is interactive. */ static int interactive_mode = 0; -/* True if SSH2 packet format is used */ -int use_ssh2_packet_format = 0; - /* Session key information for Encryption and MAC */ Newkeys *newkeys[MODE_MAX]; -void -packet_set_ssh2_format(void) -{ - DBG(debug("use_ssh2_packet_format")); - use_ssh2_packet_format = 1; - newkeys[MODE_IN] = newkeys[MODE_OUT] = NULL; -} +/* roundup current message to extra_pad bytes */ +static u_char extra_pad = 0; /* * Sets the descriptors used for communication. Disables encryption until @@ -144,9 +131,9 @@ packet_set_connection(int fd_in, int fd_out) fatal("packet_set_connection: cannot load cipher 'none'"); connection_in = fd_in; connection_out = fd_out; - cipher_type = SSH_CIPHER_NONE; - cipher_init(&send_context, none, (u_char *) "", 0, NULL, 0); - cipher_init(&receive_context, none, (u_char *) "", 0, NULL, 0); + cipher_init(&send_context, none, "", 0, NULL, 0, CIPHER_ENCRYPT); + cipher_init(&receive_context, none, "", 0, NULL, 0, CIPHER_DECRYPT); + newkeys[MODE_IN] = newkeys[MODE_OUT] = NULL; if (!initialized) { initialized = 1; buffer_init(&input); @@ -161,7 +148,7 @@ packet_set_connection(int fd_in, int fd_out) /* Returns 1 if remote host is connected via socket, 0 if not. */ int -packet_connection_is_on_socket() +packet_connection_is_on_socket(void) { struct sockaddr_storage from, to; socklen_t fromlen, tolen; @@ -187,7 +174,7 @@ packet_connection_is_on_socket() /* returns 1 if connection is via ipv4 */ int -packet_connection_is_ipv4() +packet_connection_is_ipv4(void) { struct sockaddr_storage to; socklen_t tolen = sizeof(to); @@ -203,7 +190,7 @@ packet_connection_is_ipv4() /* Sets the connection into non-blocking mode. */ void -packet_set_nonblocking() +packet_set_nonblocking(void) { /* Set the socket into non-blocking mode. */ if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0) @@ -218,7 +205,7 @@ packet_set_nonblocking() /* Returns the socket used for reading. */ int -packet_get_connection_in() +packet_get_connection_in(void) { return connection_in; } @@ -226,7 +213,7 @@ packet_get_connection_in() /* Returns the descriptor used for writing. */ int -packet_get_connection_out() +packet_get_connection_out(void) { return connection_out; } @@ -234,7 +221,7 @@ packet_get_connection_out() /* Closes the connection and clears and frees internal data structures. */ void -packet_close() +packet_close(void) { if (!initialized) return; @@ -254,6 +241,8 @@ packet_close() buffer_free(&compression_buffer); buffer_compress_uninit(); } + cipher_cleanup(&send_context); + cipher_cleanup(&receive_context); } /* Sets remote side protocol flags. */ @@ -262,13 +251,12 @@ void packet_set_protocol_flags(u_int protocol_flags) { remote_protocol_flags = protocol_flags; - channel_set_options((protocol_flags & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) != 0); } /* Returns the remote protocol flags set earlier by the above function. */ u_int -packet_get_protocol_flags() +packet_get_protocol_flags(void) { return remote_protocol_flags; } @@ -278,8 +266,8 @@ packet_get_protocol_flags() * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip. */ -void -packet_init_compression() +static void +packet_init_compression(void) { if (compression_buffer_ready == 1) return; @@ -290,7 +278,7 @@ packet_init_compression() void packet_start_compression(int level) { - if (packet_compression && !use_ssh2_packet_format) + if (packet_compression && !compat20) fatal("Compression already enabled."); packet_compression = 1; packet_init_compression(); @@ -299,43 +287,10 @@ packet_start_compression(int level) } /* - * Encrypts the given number of bytes, copying from src to dest. bytes is - * known to be a multiple of 8. - */ - -void -packet_encrypt(CipherContext * cc, void *dest, void *src, - u_int bytes) -{ - cipher_encrypt(cc, dest, src, bytes); -} - -/* - * Decrypts the given number of bytes, copying from src to dest. bytes is - * known to be a multiple of 8. - */ - -void -packet_decrypt(CipherContext *context, void *dest, void *src, u_int bytes) -{ - /* - * Cryptographic attack detector for ssh - Modifications for packet.c - * (C)1998 CORE-SDI, Buenos Aires Argentina Ariel Futoransky(futo@core-sdi.com) - */ - if (!compat20 && - context->cipher->number != SSH_CIPHER_NONE && - detect_attack(src, bytes, NULL) == DEATTACK_DETECTED) - packet_disconnect("crc32 compensation attack: network attack detected"); - - cipher_decrypt(context, dest, src, bytes); -} - -/* * Causes any further packets to be encrypted using the given key. The same * 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) @@ -345,85 +300,52 @@ packet_set_encryption_key(const u_char *key, u_int keylen, fatal("packet_set_encryption_key: unknown cipher number %d", number); if (keylen < 20) fatal("packet_set_encryption_key: keylen too small: %d", keylen); - cipher_init(&receive_context, cipher, key, keylen, NULL, 0); - cipher_init(&send_context, cipher, key, keylen, NULL, 0); -} - -/* Starts constructing a packet to send. */ - -void -packet_start1(int type) -{ - char buf[9]; - - buffer_clear(&outgoing_packet); - memset(buf, 0, 8); - buf[8] = type; - buffer_append(&outgoing_packet, buf, 9); + cipher_init(&send_context, cipher, key, keylen, NULL, 0, CIPHER_ENCRYPT); + cipher_init(&receive_context, cipher, key, keylen, NULL, 0, CIPHER_DECRYPT); } +/* Start constructing a packet to send. */ void -packet_start2(int type) +packet_start(u_char type) { - char buf[4+1+1]; - - buffer_clear(&outgoing_packet); - memset(buf, 0, sizeof buf); - /* buf[0..3] = payload_len; */ - /* buf[4] = pad_len; */ - buf[5] = type & 0xff; - buffer_append(&outgoing_packet, buf, sizeof buf); -} + u_char buf[9]; + int len; -void -packet_start(int type) -{ DBG(debug("packet_start[%d]", type)); - if (use_ssh2_packet_format) - packet_start2(type); - else - packet_start1(type); + len = compat20 ? 6 : 9; + memset(buf, 0, len - 1); + buf[len - 1] = type; + buffer_clear(&outgoing_packet); + buffer_append(&outgoing_packet, buf, len); } -/* Appends a character to the packet data. */ - +/* Append payload. */ void packet_put_char(int value) { char ch = value; buffer_append(&outgoing_packet, &ch, 1); } - -/* Appends an integer to the packet data. */ - void packet_put_int(u_int value) { buffer_put_int(&outgoing_packet, value); } - -/* Appends a string to packet data. */ - void -packet_put_string(const char *buf, u_int len) +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_string(&outgoing_packet, str, strlen(str)); + buffer_put_cstring(&outgoing_packet, str); } - void -packet_put_raw(const char *buf, u_int len) +packet_put_raw(const void *buf, u_int len) { buffer_append(&outgoing_packet, buf, len); } - - -/* Appends an arbitrary precision integer to packet data. */ - void packet_put_bignum(BIGNUM * value) { @@ -440,10 +362,10 @@ packet_put_bignum2(BIGNUM * value) * encrypts the packet before sending. */ -void +static void packet_send1(void) { - char buf[8], *cp; + u_char buf[8], *cp; int i, padding, len; u_int checksum; u_int32_t rand = 0; @@ -461,14 +383,14 @@ packet_send1(void) buffer_compress(&outgoing_packet, &compression_buffer); buffer_clear(&outgoing_packet); buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer), - buffer_len(&compression_buffer)); + buffer_len(&compression_buffer)); } /* Compute packet length without padding (add checksum, remove padding). */ len = buffer_len(&outgoing_packet) + 4 - 8; /* Insert padding. Initialized to zero in packet_start1() */ padding = 8 - len % 8; - if (cipher_type != SSH_CIPHER_NONE) { + if (!send_context.plaintext) { cp = buffer_ptr(&outgoing_packet); for (i = 0; i < padding; i++) { if (i % 4 == 0) @@ -480,7 +402,7 @@ packet_send1(void) buffer_consume(&outgoing_packet, 8 - padding); /* Add check bytes. */ - checksum = ssh_crc32((u_char *) buffer_ptr(&outgoing_packet), + checksum = ssh_crc32(buffer_ptr(&outgoing_packet), buffer_len(&outgoing_packet)); PUT_32BIT(buf, checksum); buffer_append(&outgoing_packet, buf, 4); @@ -493,9 +415,9 @@ packet_send1(void) /* Append to output. */ PUT_32BIT(buf, len); buffer_append(&output, buf, 4); - buffer_append_space(&output, &cp, buffer_len(&outgoing_packet)); - packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet), - buffer_len(&outgoing_packet)); + cp = buffer_append_space(&output, buffer_len(&outgoing_packet)); + cipher_crypt(&send_context, cp, buffer_ptr(&outgoing_packet), + buffer_len(&outgoing_packet)); #ifdef PACKET_DEBUG fprintf(stderr, "encrypted: "); @@ -511,21 +433,27 @@ packet_send1(void) */ } -void +static void set_newkeys(int mode) { Enc *enc; Mac *mac; Comp *comp; CipherContext *cc; + int encrypt; debug("newkeys: mode %d", mode); - cc = (mode == MODE_OUT) ? &send_context : &receive_context; + if (mode == MODE_OUT) { + cc = &send_context; + encrypt = CIPHER_ENCRYPT; + } else { + cc = &receive_context; + encrypt = CIPHER_DECRYPT; + } if (newkeys[mode] != NULL) { debug("newkeys: rekeying"); - /* todo: free old keys, reset compression/cipher-ctxt; */ - memset(cc, 0, sizeof(*cc)); + cipher_cleanup(cc); enc = &newkeys[mode]->enc; mac = &newkeys[mode]->mac; comp = &newkeys[mode]->comp; @@ -547,10 +475,10 @@ set_newkeys(int mode) if (mac->md != NULL) mac->enabled = 1; DBG(debug("cipher_init_context: %d", mode)); - cipher_init(cc, enc->cipher, enc->key, enc->cipher->key_len, - enc->iv, enc->cipher->block_size); - memset(enc->iv, 0, enc->cipher->block_size); - memset(enc->key, 0, enc->cipher->key_len); + cipher_init(cc, enc->cipher, enc->key, enc->key_len, + enc->iv, enc->block_size, encrypt); + memset(enc->iv, 0, enc->block_size); + memset(enc->key, 0, enc->key_len); if (comp->type != 0 && comp->enabled == 0) { packet_init_compression(); if (mode == MODE_OUT) @@ -564,16 +492,15 @@ set_newkeys(int mode) /* * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue) */ -void +static void packet_send2(void) { static u_int32_t seqnr = 0; - u_char *macbuf = NULL; - char *cp; + u_char type, *cp, *macbuf = NULL; + u_char padlen, pad; u_int packet_length = 0; - u_int i, padlen, len; + u_int i, len; u_int32_t rand = 0; - int type; Enc *enc = NULL; Mac *mac = NULL; Comp *comp = NULL; @@ -584,10 +511,10 @@ packet_send2(void) mac = &newkeys[MODE_OUT]->mac; comp = &newkeys[MODE_OUT]->comp; } - block_size = enc ? enc->cipher->block_size : 8; + block_size = enc ? enc->block_size : 8; cp = buffer_ptr(&outgoing_packet); - type = cp[5] & 0xff; + type = cp[5]; #ifdef PACKET_DEBUG fprintf(stderr, "plain: "); @@ -618,8 +545,17 @@ packet_send2(void) padlen = block_size - (len % block_size); if (padlen < 4) padlen += block_size; - buffer_append_space(&outgoing_packet, &cp, padlen); - if (enc && enc->cipher->number != SSH_CIPHER_NONE) { + if (extra_pad) { + /* will wrap if extra_pad+padlen > 255 */ + extra_pad = roundup(extra_pad, block_size); + pad = extra_pad - ((len + padlen) % extra_pad); + debug("packet_send2: adding %d (len %d padlen %d extra_pad %d)", + pad, len, padlen, extra_pad); + padlen += pad; + extra_pad = 0; + } + cp = buffer_append_space(&outgoing_packet, padlen); + if (enc && !send_context.plaintext) { /* random padding */ for (i = 0; i < padlen; i++) { if (i % 4 == 0) @@ -635,19 +571,19 @@ packet_send2(void) packet_length = buffer_len(&outgoing_packet) - 4; cp = buffer_ptr(&outgoing_packet); PUT_32BIT(cp, packet_length); - cp[4] = padlen & 0xff; + 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, seqnr, - (u_char *) buffer_ptr(&outgoing_packet), + buffer_ptr(&outgoing_packet), buffer_len(&outgoing_packet)); DBG(debug("done calc MAC out #%d", seqnr)); } /* encrypt packet and append to output buffer. */ - buffer_append_space(&output, &cp, buffer_len(&outgoing_packet)); - packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet), + cp = buffer_append_space(&output, buffer_len(&outgoing_packet)); + cipher_crypt(&send_context, cp, buffer_ptr(&outgoing_packet), buffer_len(&outgoing_packet)); /* append unencrypted MAC */ if (mac && mac->enabled) @@ -666,9 +602,9 @@ packet_send2(void) } void -packet_send() +packet_send(void) { - if (use_ssh2_packet_format) + if (compat20) packet_send2(); else packet_send1(); @@ -682,7 +618,7 @@ packet_send() */ int -packet_read(int *payload_len_ptr) +packet_read_seqnr(u_int32_t *seqnr_p) { int type, len; fd_set *setp; @@ -698,13 +634,13 @@ packet_read(int *payload_len_ptr) /* Stay in the loop until we have received a complete packet. */ for (;;) { /* Try to read a packet from the buffer. */ - type = packet_read_poll(payload_len_ptr); - if (!use_ssh2_packet_format && ( + type = packet_read_poll_seqnr(seqnr_p); + if (!compat20 && ( type == SSH_SMSG_SUCCESS || type == SSH_SMSG_FAILURE || type == SSH_CMSG_EOF || type == SSH_CMSG_EXIT_CONFIRMATION)) - packet_integrity_check(*payload_len_ptr, 0, type); + packet_check_eom(); /* If we got a packet, return it. */ if (type != SSH_MSG_NONE) { xfree(setp); @@ -737,17 +673,23 @@ packet_read(int *payload_len_ptr) /* NOTREACHED */ } +int +packet_read(void) +{ + return packet_read_seqnr(NULL); +} + /* * Waits until a packet has been received, verifies that its type matches * that given, and gives a fatal error and exits if there is a mismatch. */ void -packet_read_expect(int *payload_len_ptr, int expected_type) +packet_read_expect(int expected_type) { int type; - type = packet_read(payload_len_ptr); + type = packet_read(); if (type != expected_type) packet_disconnect("Protocol error: expected packet type %d, got %d", expected_type, type); @@ -760,28 +702,21 @@ packet_read_expect(int *payload_len_ptr, int expected_type) * SSH_MSG_DISCONNECT is handled specially here. Also, * SSH_MSG_IGNORE messages are skipped by this function and are never returned * to higher levels. - * - * The returned payload_len does include space consumed by: - * Packet length - * Padding - * Packet type - * Check bytes */ -int -packet_read_poll1(int *payload_len_ptr) +static int +packet_read_poll1(void) { u_int len, padded_len; - u_char *ucp; - char buf[8], *cp; + u_char *cp, type; u_int checksum, stored_checksum; /* Check if input size is less than minimum packet size. */ if (buffer_len(&input) < 4 + 8) return SSH_MSG_NONE; /* Get length of incoming packet. */ - ucp = (u_char *) buffer_ptr(&input); - len = GET_32BIT(ucp); + cp = buffer_ptr(&input); + len = GET_32BIT(cp); if (len < 1 + 2 + 2 || len > 256 * 1024) packet_disconnect("Bad packet length %d.", len); padded_len = (len + 8) & ~7; @@ -795,10 +730,20 @@ packet_read_poll1(int *payload_len_ptr) /* Consume packet length. */ buffer_consume(&input, 4); - /* Copy data to incoming_packet. */ + /* + * Cryptographic attack detector for ssh + * (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"); + + /* Decrypt data to incoming_packet. */ buffer_clear(&incoming_packet); - buffer_append_space(&incoming_packet, &cp, padded_len); - packet_decrypt(&receive_context, cp, buffer_ptr(&input), padded_len); + cp = buffer_append_space(&incoming_packet, padded_len); + cipher_crypt(&receive_context, cp, buffer_ptr(&input), padded_len); + buffer_consume(&input, padded_len); #ifdef PACKET_DEBUG @@ -807,25 +752,23 @@ packet_read_poll1(int *payload_len_ptr) #endif /* Compute packet checksum. */ - checksum = ssh_crc32((u_char *) buffer_ptr(&incoming_packet), + checksum = ssh_crc32(buffer_ptr(&incoming_packet), buffer_len(&incoming_packet) - 4); /* Skip padding. */ buffer_consume(&incoming_packet, 8 - len % 8); /* Test check bytes. */ - if (len != buffer_len(&incoming_packet)) - packet_disconnect("packet_read_poll: len %d != buffer_len %d.", + packet_disconnect("packet_read_poll1: len %d != buffer_len %d.", len, buffer_len(&incoming_packet)); - ucp = (u_char *) buffer_ptr(&incoming_packet) + len - 4; - stored_checksum = GET_32BIT(ucp); + cp = (u_char *)buffer_ptr(&incoming_packet) + len - 4; + stored_checksum = GET_32BIT(cp); if (checksum != stored_checksum) packet_disconnect("Corrupted check bytes on input."); buffer_consume_end(&incoming_packet, 4); - /* If using packet compression, decompress the packet. */ if (packet_compression) { buffer_clear(&compression_buffer); buffer_uncompress(&incoming_packet, &compression_buffer); @@ -833,26 +776,17 @@ packet_read_poll1(int *payload_len_ptr) buffer_append(&incoming_packet, buffer_ptr(&compression_buffer), buffer_len(&compression_buffer)); } - /* Get packet type. */ - buffer_get(&incoming_packet, &buf[0], 1); - - /* Return length of payload (without type field). */ - *payload_len_ptr = buffer_len(&incoming_packet); - - /* Return type. */ - return (u_char) buf[0]; + type = buffer_get_char(&incoming_packet); + return type; } -int -packet_read_poll2(int *payload_len_ptr) +static int +packet_read_poll2(u_int32_t *seqnr_p) { static u_int32_t seqnr = 0; static u_int packet_length = 0; u_int padlen, need; - u_char buf[8], *macbuf; - u_char *ucp; - char *cp; - int type; + u_char *macbuf, *cp, type; int maclen, block_size; Enc *enc = NULL; Mac *mac = NULL; @@ -864,7 +798,7 @@ packet_read_poll2(int *payload_len_ptr) comp = &newkeys[MODE_IN]->comp; } maclen = mac && mac->enabled ? mac->mac_len : 0; - block_size = enc ? enc->cipher->block_size : 8; + block_size = enc ? enc->block_size : 8; if (packet_length == 0) { /* @@ -874,11 +808,11 @@ packet_read_poll2(int *payload_len_ptr) if (buffer_len(&input) < block_size) return SSH_MSG_NONE; buffer_clear(&incoming_packet); - buffer_append_space(&incoming_packet, &cp, block_size); - packet_decrypt(&receive_context, cp, buffer_ptr(&input), + cp = buffer_append_space(&incoming_packet, block_size); + cipher_crypt(&receive_context, cp, buffer_ptr(&input), block_size); - ucp = (u_char *) buffer_ptr(&incoming_packet); - packet_length = GET_32BIT(ucp); + cp = buffer_ptr(&incoming_packet); + packet_length = GET_32BIT(cp); if (packet_length < 1 + 4 || packet_length > 256 * 1024) { buffer_dump(&incoming_packet); packet_disconnect("Bad packet length %d.", packet_length); @@ -903,8 +837,8 @@ packet_read_poll2(int *payload_len_ptr) fprintf(stderr, "read_poll enc/full: "); buffer_dump(&input); #endif - buffer_append_space(&incoming_packet, &cp, need); - packet_decrypt(&receive_context, cp, buffer_ptr(&input), need); + cp = buffer_append_space(&incoming_packet, need); + cipher_crypt(&receive_context, cp, buffer_ptr(&input), need); buffer_consume(&input, need); /* * compute MAC over seqnr and packet, @@ -912,19 +846,21 @@ packet_read_poll2(int *payload_len_ptr) */ if (mac && mac->enabled) { macbuf = mac_compute(mac, seqnr, - (u_char *) buffer_ptr(&incoming_packet), + 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", seqnr)); buffer_consume(&input, mac->mac_len); } + if (seqnr_p != NULL) + *seqnr_p = seqnr; if (++seqnr == 0) log("incoming seqnr wraps around"); /* get padlen */ - cp = buffer_ptr(&incoming_packet) + 4; - padlen = *cp & 0xff; + cp = buffer_ptr(&incoming_packet); + padlen = cp[4]; DBG(debug("input: padlen %d", padlen)); if (padlen < 4) packet_disconnect("Corrupted padlen %d on input.", padlen); @@ -946,39 +882,31 @@ packet_read_poll2(int *payload_len_ptr) * get packet type, implies consume. * return length of payload (without type field) */ - buffer_get(&incoming_packet, (char *)&buf[0], 1); - *payload_len_ptr = buffer_len(&incoming_packet); - - /* reset for next packet */ - packet_length = 0; - - /* extract packet type */ - type = (u_char)buf[0]; - + type = buffer_get_char(&incoming_packet); if (type == SSH2_MSG_NEWKEYS) set_newkeys(MODE_IN); - #ifdef PACKET_DEBUG fprintf(stderr, "read/plain[%d]:\r\n", type); buffer_dump(&incoming_packet); #endif - return (u_char)type; + /* reset for next packet */ + packet_length = 0; + return type; } int -packet_read_poll(int *payload_len_ptr) +packet_read_poll_seqnr(u_int32_t *seqnr_p) { + int reason, seqnr; + u_char type; char *msg; - for (;;) { - int type = use_ssh2_packet_format ? - packet_read_poll2(payload_len_ptr): - packet_read_poll1(payload_len_ptr); - if(compat20) { - int reason; - if (type != 0) + for (;;) { + if (compat20) { + type = packet_read_poll2(seqnr_p); + if (type) DBG(debug("received packet type %d", type)); - switch(type) { + switch (type) { case SSH2_MSG_IGNORE: break; case SSH2_MSG_DEBUG: @@ -997,12 +925,17 @@ packet_read_poll(int *payload_len_ptr) xfree(msg); fatal_cleanup(); break; + case SSH2_MSG_UNIMPLEMENTED: + seqnr = packet_get_int(); + debug("Received SSH2_MSG_UNIMPLEMENTED for %d", seqnr); + break; default: return type; break; } } else { - switch(type) { + type = packet_read_poll1(); + switch (type) { case SSH_MSG_IGNORE: break; case SSH_MSG_DEBUG: @@ -1018,7 +951,7 @@ packet_read_poll(int *payload_len_ptr) xfree(msg); break; default: - if (type != 0) + if (type) DBG(debug("received packet type %d", type)); return type; break; @@ -1027,6 +960,12 @@ packet_read_poll(int *payload_len_ptr) } } +int +packet_read_poll(void) +{ + return packet_read_poll_seqnr(NULL); +} + /* * Buffers the given amount of input characters. This is intended to be used * together with packet_read_poll. @@ -1041,7 +980,7 @@ packet_process_incoming(const char *buf, u_int len) /* Returns a character from the packet. */ u_int -packet_get_char() +packet_get_char(void) { char ch; buffer_get(&incoming_packet, &ch, 1); @@ -1051,7 +990,7 @@ packet_get_char() /* Returns an integer from the packet data. */ u_int -packet_get_int() +packet_get_int(void) { return buffer_get_int(&incoming_packet); } @@ -1062,18 +1001,18 @@ packet_get_int() */ void -packet_get_bignum(BIGNUM * value, int *length_ptr) +packet_get_bignum(BIGNUM * value) { - *length_ptr = buffer_get_bignum(&incoming_packet, value); + buffer_get_bignum(&incoming_packet, value); } void -packet_get_bignum2(BIGNUM * value, int *length_ptr) +packet_get_bignum2(BIGNUM * value) { - *length_ptr = buffer_get_bignum2(&incoming_packet, value); + buffer_get_bignum2(&incoming_packet, value); } -char * +void * packet_get_raw(int *length_ptr) { int bytes = buffer_len(&incoming_packet); @@ -1095,7 +1034,7 @@ packet_remaining(void) * integer into which the length of the string is stored. */ -char * +void * packet_get_string(u_int *length_ptr) { return buffer_get_string(&incoming_packet, length_ptr); @@ -1169,13 +1108,13 @@ packet_disconnect(const char *fmt,...) packet_put_cstring(""); } else { packet_start(SSH_MSG_DISCONNECT); - packet_put_string(buf, strlen(buf)); + packet_put_cstring(buf); } packet_send(); packet_write_wait(); /* Stop listening for connections. */ - channel_stop_listening(); + channel_close_all(); /* Close the connection. */ packet_close(); @@ -1188,7 +1127,7 @@ packet_disconnect(const char *fmt,...) /* Checks if there is any buffered output, and tries to write some of the output. */ void -packet_write_poll() +packet_write_poll(void) { int len = buffer_len(&output); if (len > 0) { @@ -1209,7 +1148,7 @@ packet_write_poll() */ void -packet_write_wait() +packet_write_wait(void) { fd_set *setp; @@ -1231,7 +1170,7 @@ packet_write_wait() /* Returns true if there is buffered data to write to the connection. */ int -packet_have_data_to_write() +packet_have_data_to_write(void) { return buffer_len(&output) != 0; } @@ -1239,7 +1178,7 @@ packet_have_data_to_write() /* Returns true if there is not too much data to write to the connection. */ int -packet_not_very_much_data_to_write() +packet_not_very_much_data_to_write(void) { if (interactive_mode) return buffer_len(&output) < 16384; @@ -1255,7 +1194,6 @@ packet_set_interactive(int interactive) static int called = 0; int lowdelay = IPTOS_LOWDELAY; int throughput = IPTOS_THROUGHPUT; - int on = 1; if (called) return; @@ -1277,19 +1215,17 @@ packet_set_interactive(int interactive) */ if (packet_connection_is_ipv4()) { if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, - (void *) &lowdelay, sizeof(lowdelay)) < 0) + &lowdelay, sizeof(lowdelay)) < 0) error("setsockopt IPTOS_LOWDELAY: %.100s", strerror(errno)); } - if (setsockopt(connection_in, IPPROTO_TCP, TCP_NODELAY, (void *) &on, - sizeof(on)) < 0) - error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); + set_nodelay(connection_in); } else if (packet_connection_is_ipv4()) { /* * Set IP options for a non-interactive connection. Use * IPTOS_THROUGHPUT. */ - if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *) &throughput, + if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, &throughput, sizeof(throughput)) < 0) error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno)); } @@ -1298,7 +1234,7 @@ packet_set_interactive(int interactive) /* Returns true if the current connection is interactive. */ int -packet_is_interactive() +packet_is_interactive(void) { return interactive_mode; } @@ -1316,11 +1252,19 @@ packet_set_maxsize(int s) log("packet_set_maxsize: bad size %d", s); return -1; } - log("packet_set_maxsize: setting to %d", s); + called = 1; + debug("packet_set_maxsize: setting to %d", s); max_packet_size = s; return s; } +/* roundup current message to pad bytes */ +void +packet_add_padding(u_char pad) +{ + extra_pad = pad; +} + /* * 9.2. Ignored Data Message * @@ -1332,41 +1276,6 @@ packet_set_maxsize(int s) * required to send them. This message can be used as an additional * protection measure against advanced traffic analysis techniques. */ -/* size of current + ignore message should be n*sumlen bytes (w/o mac) */ -void -packet_inject_ignore(int sumlen) -{ - int blocksize, padlen, have, need, nb, mini, nbytes; - Enc *enc = NULL; - - if (use_ssh2_packet_format == 0) - return; - - have = buffer_len(&outgoing_packet); - debug2("packet_inject_ignore: current %d", have); - if (newkeys[MODE_OUT] != NULL) - enc = &newkeys[MODE_OUT]->enc; - blocksize = enc ? enc->cipher->block_size : 8; - padlen = blocksize - (have % blocksize); - if (padlen < 4) - padlen += blocksize; - have += padlen; - have /= blocksize; /* # of blocks for current message */ - - nb = roundup(sumlen, blocksize) / blocksize; /* blocks for both */ - mini = roundup(5+1+4+4, blocksize) / blocksize; /* minsize ignore msg */ - need = nb - (have % nb); /* blocks for ignore */ - if (need <= mini) - need += nb; - nbytes = (need - mini) * blocksize; /* size of ignore payload */ - debug2("packet_inject_ignore: block %d have %d nb %d mini %d need %d", - blocksize, have, nb, mini, need); - - /* enqueue current message and append a ignore message */ - packet_send(); - packet_send_ignore(nbytes); -} - void packet_send_ignore(int nbytes) { @@ -1375,7 +1284,7 @@ packet_send_ignore(int nbytes) packet_start(compat20 ? SSH2_MSG_IGNORE : SSH_MSG_IGNORE); packet_put_int(nbytes); - for(i = 0; i < nbytes; i++) { + for (i = 0; i < nbytes; i++) { if (i % 4 == 0) rand = arc4random(); packet_put_char(rand & 0xff); |
