X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/52e3daedec4da996f923934417982ace52d0b981..575a5eced126099bed926a05ff174b7a8c9f1612:/packet.c diff --git a/packet.c b/packet.c index 40c6b1d2..6afe24b9 100644 --- a/packet.c +++ b/packet.c @@ -1,3 +1,4 @@ +/* $OpenBSD: packet.c,v 1.151 2008/02/22 20:44:02 dtucker Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -38,26 +39,38 @@ #include "includes.h" +#include #include "openbsd-compat/sys-queue.h" -#include +#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" @@ -123,6 +136,8 @@ static int server_side = 0; /* Set to true if we are authenticated. */ static int after_authentication = 0; +int keep_alive_timeouts = 0; + /* Session key information for Encryption and MAC */ Newkeys *newkeys[MODE_MAX]; static struct packet_state { @@ -558,7 +573,7 @@ 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 @@ -567,7 +582,7 @@ 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), @@ -616,7 +631,7 @@ set_newkeys(int mode) 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); @@ -631,14 +646,15 @@ 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, crypt_type); /* Deleting the keys does not gain extra security */ /* memset(enc->iv, 0, enc->block_size); - memset(enc->key, 0, enc->key_len); */ + 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) { @@ -663,7 +679,7 @@ set_newkeys(int mode) /* * Delayed compression for SSH2 is enabled after authentication: - * This happans on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent, + * 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 @@ -678,6 +694,9 @@ packet_enable_delayed_compress(void) */ 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(); @@ -770,7 +789,7 @@ packet_send2_wrapped(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)); @@ -787,7 +806,7 @@ packet_send2_wrapped(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); @@ -968,7 +987,7 @@ 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 %u.", len); padded_len = (len + 8) & ~7; @@ -987,9 +1006,16 @@ 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) == 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); @@ -1016,7 +1042,7 @@ 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); @@ -1065,7 +1091,7 @@ 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); @@ -1168,10 +1194,12 @@ packet_read_poll_seqnr(u_int32_t *seqnr_p) for (;;) { if (compat20) { type = packet_read_poll2(seqnr_p); + keep_alive_timeouts = 0; if (type) DBG(debug("received packet type %d", type)); switch (type) { case SSH2_MSG_IGNORE: + debug3("Received SSH2_MSG_IGNORE"); break; case SSH2_MSG_DEBUG: packet_get_char(); @@ -1212,7 +1240,6 @@ packet_read_poll_seqnr(u_int32_t *seqnr_p) logit("Received disconnect from %s: %.400s", get_remote_ipaddr(), msg); cleanup_exit(255); - xfree(msg); break; default: if (type) @@ -1548,7 +1575,7 @@ packet_send_ignore(int nbytes) for (i = 0; i < nbytes; i++) { if (i % 4 == 0) rnd = arc4random(); - packet_put_char(rnd & 0xff); + packet_put_char((u_char)rnd & 0xff); rnd >>= 8; } }