dropbear: packet.c annotate

annotate packet.c @ 45:9ee8996a375f

Pubkey auth is mostly there for the client. Something strange with remote hostkey verification though.

author	Matt Johnston <matt@ucc.asn.au>
date	Tue, 03 Aug 2004 17:26:56 +0000
parents	f789045062e6
children	b0316ce64e4b

rev	line source
27 08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	1 /*
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	2 * Dropbear - a SSH2 server
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	3 *
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	4 * Copyright (c) 2002,2003 Matt Johnston
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	5 * All rights reserved.
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	6 *
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	7 * Permission is hereby granted, free of charge, to any person obtaining a copy
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	8 * of this software and associated documentation files (the "Software"), to deal
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	9 * in the Software without restriction, including without limitation the rights
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	11 * copies of the Software, and to permit persons to whom the Software is
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	12 * furnished to do so, subject to the following conditions:
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	13 *
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	14 * The above copyright notice and this permission notice shall be included in
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	15 * all copies or substantial portions of the Software.
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	16 *
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	23 * SOFTWARE. */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	24
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	25 #include "includes.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	26 #include "packet.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	27 #include "session.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	28 #include "dbutil.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	29 #include "ssh.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	30 #include "algo.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	31 #include "buffer.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	32 #include "kex.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	33 #include "random.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	34 #include "service.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	35 #include "auth.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	36 #include "channel.h"
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	37
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	38 static void read_packet_init();
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	39 static void writemac(buffer * outputbuffer, buffer * clearwritebuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	40 static int checkmac(buffer* hashbuf, buffer* readbuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	41
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	42 #define ZLIB_COMPRESS_INCR 20 /* this is 12 bytes + 0.1% of 8000 bytes */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	43 #define ZLIB_DECOMPRESS_INCR 100
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	44 #ifndef DISABLE_ZLIB
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	45 static buffer* buf_decompress(buffer* buf, unsigned int len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	46 static void buf_compress(buffer * dest, buffer * src, unsigned int len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	47 #endif
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	48
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	49 /* non-blocking function writing out a current encrypted packet */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	50 void write_packet() {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	51
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	52 int len, written;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	53 buffer * writebuf;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	54
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	55 TRACE(("enter write_packet"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	56 assert(!isempty(&ses.writequeue));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	57
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	58 /* Get the next buffer in the queue of encrypted packets to write*/
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	59 writebuf = (buffer*)examine(&ses.writequeue);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	60
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	61 len = writebuf->len - writebuf->pos;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	62 assert(len > 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	63 /* Try to write as much as possible */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	64 written = write(ses.sock, buf_getptr(writebuf, len), len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	65
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	66 if (written < 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	67 if (errno == EINTR) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	68 TRACE(("leave writepacket: EINTR"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	69 return;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	70 } else {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	71 dropbear_exit("error writing");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	72 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	73 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	74
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	75 if (written == 0) {
33 f789045062e6 Progressing client support Matt Johnston <matt@ucc.asn.au> parents: 27 diff changeset	76 ses.remoteclosed();
27 08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	77 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	78
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	79 if (written == len) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	80 /* We've finished with the packet, free it */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	81 dequeue(&ses.writequeue);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	82 buf_free(writebuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	83 } else {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	84 /* More packet left to write, leave it in the queue for later */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	85 buf_incrpos(writebuf, written);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	86 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	87
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	88 TRACE(("leave write_packet"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	89 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	90
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	91 /* Non-blocking function reading available portion of a packet into the
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	92 * ses's buffer, decrypting the length if encrypted, decrypting the
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	93 * full portion if possible */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	94 void read_packet() {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	95
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	96 int len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	97 unsigned int maxlen;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	98 unsigned char blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	99
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	100 TRACE(("enter read_packet"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	101 blocksize = ses.keys->recv_algo_crypt->blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	102
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	103 if (ses.readbuf == NULL \|\| ses.readbuf->len < blocksize) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	104 /* In the first blocksize of a packet */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	105
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	106 /* Read the first blocksize of the packet, so we can decrypt it and
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	107 * find the length of the whole packet */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	108 read_packet_init();
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	109
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	110 /* If we don't have the length of decryptreadbuf, we didn't read
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	111 * a whole blocksize and should exit */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	112 if (ses.decryptreadbuf->len == 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	113 TRACE(("leave read_packet: packetinit done"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	114 return;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	115 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	116 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	117
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	118 /* Attempt to read the remainder of the packet, note that there
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	119 * mightn't be any available (EAGAIN) */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	120 assert(ses.readbuf != NULL);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	121 maxlen = ses.readbuf->len - ses.readbuf->pos;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	122 len = read(ses.sock, buf_getptr(ses.readbuf, maxlen), maxlen);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	123
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	124 if (len == 0) {
33 f789045062e6 Progressing client support Matt Johnston <matt@ucc.asn.au> parents: 27 diff changeset	125 ses.remoteclosed();
27 08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	126 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	127
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	128 if (len < 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	129 if (errno == EINTR \|\| errno == EAGAIN) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	130 TRACE(("leave read_packet: EINTR or EAGAIN"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	131 return;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	132 } else {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	133 dropbear_exit("error reading: %s", strerror(errno));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	134 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	135 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	136
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	137 buf_incrpos(ses.readbuf, len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	138
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	139 if ((unsigned int)len == maxlen) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	140 /* The whole packet has been read */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	141 decrypt_packet();
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	142 /* The main select() loop process_packet() to
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	143 * handle the packet contents... */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	144 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	145 TRACE(("leave read_packet"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	146 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	147
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	148 /* Function used to read the initial portion of a packet, and determine the
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	149 * length. Only called during the first BLOCKSIZE of a packet. */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	150 static void read_packet_init() {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	151
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	152 unsigned int maxlen;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	153 int len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	154 unsigned char blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	155 unsigned char macsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	156
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	157
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	158 blocksize = ses.keys->recv_algo_crypt->blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	159 macsize = ses.keys->recv_algo_mac->hashsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	160
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	161 if (ses.readbuf == NULL) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	162 /* start of a new packet */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	163 ses.readbuf = buf_new(INIT_READBUF);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	164 assert(ses.decryptreadbuf == NULL);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	165 ses.decryptreadbuf = buf_new(blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	166 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	167
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	168 maxlen = blocksize - ses.readbuf->pos;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	169
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	170 /* read the rest of the packet if possible */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	171 len = read(ses.sock, buf_getwriteptr(ses.readbuf, maxlen),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	172 maxlen);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	173 if (len == 0) {
33 f789045062e6 Progressing client support Matt Johnston <matt@ucc.asn.au> parents: 27 diff changeset	174 ses.remoteclosed();
27 08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	175 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	176 if (len < 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	177 if (errno == EINTR) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	178 TRACE(("leave read_packet_init: EINTR"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	179 return;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	180 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	181 dropbear_exit("error reading: %s", strerror(errno));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	182 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	183
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	184 buf_incrwritepos(ses.readbuf, len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	185
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	186 if ((unsigned int)len != maxlen) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	187 /* don't have enough bytes to determine length, get next time */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	188 return;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	189 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	190
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	191 /* now we have the first block, need to get packet length, so we decrypt
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	192 * the first block (only need first 4 bytes) */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	193 buf_setpos(ses.readbuf, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	194 if (ses.keys->recv_algo_crypt->cipherdesc == NULL) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	195 /* copy it */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	196 memcpy(buf_getwriteptr(ses.decryptreadbuf, blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	197 buf_getptr(ses.readbuf, blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	198 blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	199 } else {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	200 /* decrypt it */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	201 if (cbc_decrypt(buf_getptr(ses.readbuf, blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	202 buf_getwriteptr(ses.decryptreadbuf,blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	203 &ses.keys->recv_symmetric_struct) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	204 dropbear_exit("error decrypting");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	205 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	206 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	207 buf_setlen(ses.decryptreadbuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	208 len = buf_getint(ses.decryptreadbuf) + 4 + macsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	209
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	210 buf_setpos(ses.readbuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	211
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	212 /* check packet length */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	213 if ((len > MAX_PACKET_LEN) \|\|
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	214 (len < MIN_PACKET_LEN + macsize) \|\|
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	215 ((len - macsize) % blocksize != 0)) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	216 dropbear_exit("bad packet size");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	217 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	218
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	219 buf_resize(ses.readbuf, len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	220 buf_setlen(ses.readbuf, len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	221
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	222 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	223
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	224 /* handle the received packet */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	225 void decrypt_packet() {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	226
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	227 unsigned char blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	228 unsigned char macsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	229 unsigned int padlen;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	230 unsigned int len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	231
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	232 TRACE(("enter decrypt_packet"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	233 blocksize = ses.keys->recv_algo_crypt->blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	234 macsize = ses.keys->recv_algo_mac->hashsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	235
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	236 ses.kexstate.datarecv += ses.readbuf->len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	237
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	238 /* we've already decrypted the first blocksize in read_packet_init */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	239 buf_setpos(ses.readbuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	240
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	241 buf_resize(ses.decryptreadbuf, ses.readbuf->len - macsize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	242 buf_setlen(ses.decryptreadbuf, ses.decryptreadbuf->size);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	243 buf_setpos(ses.decryptreadbuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	244
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	245 /* decrypt if encryption is set, memcpy otherwise */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	246 if (ses.keys->recv_algo_crypt->cipherdesc == NULL) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	247 /* copy it */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	248 len = ses.readbuf->len - macsize - blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	249 memcpy(buf_getwriteptr(ses.decryptreadbuf, len),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	250 buf_getptr(ses.readbuf, len), len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	251 } else {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	252 /* decrypt */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	253 while (ses.readbuf->pos < ses.readbuf->len - macsize) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	254 if (cbc_decrypt(buf_getptr(ses.readbuf, blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	255 buf_getwriteptr(ses.decryptreadbuf, blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	256 &ses.keys->recv_symmetric_struct) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	257 dropbear_exit("error decrypting");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	258 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	259 buf_incrpos(ses.readbuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	260 buf_incrwritepos(ses.decryptreadbuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	261 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	262 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	263
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	264 /* check the hmac */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	265 buf_setpos(ses.readbuf, ses.readbuf->len - macsize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	266 if (checkmac(ses.readbuf, ses.decryptreadbuf) != DROPBEAR_SUCCESS) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	267 dropbear_exit("Integrity error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	268 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	269
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	270 /* readbuf no longer required */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	271 buf_free(ses.readbuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	272 ses.readbuf = NULL;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	273
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	274 /* get padding length */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	275 buf_setpos(ses.decryptreadbuf, PACKET_PADDING_OFF);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	276 padlen = buf_getbyte(ses.decryptreadbuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	277
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	278 /* payload length */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	279 /* - 4 - 1 is for LEN and PADLEN values */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	280 len = ses.decryptreadbuf->len - padlen - 4 - 1;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	281 if ((len > MAX_PAYLOAD_LEN) \|\| (len < 1)) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	282 dropbear_exit("bad packet size");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	283 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	284
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	285 buf_setpos(ses.decryptreadbuf, PACKET_PAYLOAD_OFF);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	286
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	287 #ifndef DISABLE_ZLIB
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	288 if (ses.keys->recv_algo_comp == DROPBEAR_COMP_ZLIB) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	289 /* decompress */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	290 ses.payload = buf_decompress(ses.decryptreadbuf, len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	291
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	292 } else
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	293 #endif
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	294 {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	295 /* copy payload */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	296 ses.payload = buf_new(len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	297 memcpy(ses.payload->data, buf_getptr(ses.decryptreadbuf, len), len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	298 buf_incrlen(ses.payload, len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	299 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	300
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	301 buf_free(ses.decryptreadbuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	302 ses.decryptreadbuf = NULL;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	303 buf_setpos(ses.payload, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	304
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	305 ses.recvseq++;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	306
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	307 TRACE(("leave decrypt_packet"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	308 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	309
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	310 /* Checks the mac in hashbuf, for the data in readbuf.
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	311 * Returns DROPBEAR_SUCCESS or DROPBEAR_FAILURE */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	312 static int checkmac(buffer* macbuf, buffer* sourcebuf) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	313
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	314 unsigned char macsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	315 hmac_state hmac;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	316 unsigned char tempbuf[MAX_MAC_LEN];
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	317 unsigned long hashsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	318 int len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	319
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	320 macsize = ses.keys->recv_algo_mac->hashsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	321
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	322 if (macsize == 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	323 return DROPBEAR_SUCCESS;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	324 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	325
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	326 /* calculate the mac */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	327 if (hmac_init(&hmac,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	328 find_hash(ses.keys->recv_algo_mac->hashdesc->name),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	329 ses.keys->recvmackey,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	330 ses.keys->recv_algo_mac->keysize)
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	331 != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	332 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	333 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	334
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	335 /* sequence number */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	336 STORE32H(ses.recvseq, tempbuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	337 if (hmac_process(&hmac, tempbuf, 4) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	338 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	339 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	340
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	341 buf_setpos(sourcebuf, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	342 len = sourcebuf->len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	343 if (hmac_process(&hmac, buf_getptr(sourcebuf, len), len) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	344 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	345 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	346
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	347 hashsize = sizeof(tempbuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	348 if (hmac_done(&hmac, tempbuf, &hashsize) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	349 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	350 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	351
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	352 /* compare the hash */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	353 if (memcmp(tempbuf, buf_getptr(macbuf, macsize), macsize) != 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	354 return DROPBEAR_FAILURE;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	355 } else {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	356 return DROPBEAR_SUCCESS;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	357 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	358 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	359
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	360 #ifndef DISABLE_ZLIB
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	361 /* returns a pointer to a newly created buffer */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	362 static buffer* buf_decompress(buffer* buf, unsigned int len) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	363
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	364 int result;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	365 buffer * ret;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	366 z_streamp zstream;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	367
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	368 zstream = ses.keys->recv_zstream;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	369 ret = buf_new(len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	370
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	371 zstream->avail_in = len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	372 zstream->next_in = buf_getptr(buf, len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	373
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	374 /* decompress the payload, incrementally resizing the output buffer */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	375 while (1) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	376
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	377 zstream->avail_out = ret->size - ret->pos;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	378 zstream->next_out = buf_getwriteptr(ret, zstream->avail_out);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	379
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	380 result = inflate(zstream, Z_SYNC_FLUSH);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	381
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	382 buf_setlen(ret, ret->size - zstream->avail_out);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	383 buf_setpos(ret, ret->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	384
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	385 if (result != Z_BUF_ERROR && result != Z_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	386 dropbear_exit("zlib error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	387 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	388
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	389 if (zstream->avail_in == 0 &&
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	390 (zstream->avail_out != 0 \|\| result == Z_BUF_ERROR)) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	391 /* we can only exit if avail_out hasn't all been used,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	392 * and there's no remaining input */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	393 return ret;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	394 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	395
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	396 if (zstream->avail_out == 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	397 buf_resize(ret, ret->size + ZLIB_DECOMPRESS_INCR);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	398 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	399 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	400 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	401 #endif
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	402
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	403
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	404
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	405
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	406 /* encrypt the writepayload, putting into writebuf, ready for write_packet()
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	407 * to put on the wire */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	408 void encrypt_packet() {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	409
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	410 unsigned char padlen;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	411 unsigned char blocksize, macsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	412 buffer * writebuf; /* the packet which will go on the wire */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	413 buffer * clearwritebuf; /* unencrypted, possibly compressed */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	414
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	415 TRACE(("enter encrypt_packet()"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	416 TRACE(("encrypt_packet type is %d", ses.writepayload->data[0]));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	417 blocksize = ses.keys->trans_algo_crypt->blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	418 macsize = ses.keys->trans_algo_mac->hashsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	419
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	420 /* Encrypted packet len is payload+5, then worst case is if we are 3 away
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	421 * from a blocksize multiple. In which case we need to pad to the
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	422 * multiple, then add another blocksize (or MIN_PACKET_LEN) */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	423 clearwritebuf = buf_new((ses.writepayload->len+4+1) + MIN_PACKET_LEN + 3
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	424 #ifndef DISABLE_ZLIB
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	425 + ZLIB_COMPRESS_INCR /* bit of a kludge, but we can't know len*/
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	426 #endif
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	427 );
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	428 buf_setlen(clearwritebuf, PACKET_PAYLOAD_OFF);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	429 buf_setpos(clearwritebuf, PACKET_PAYLOAD_OFF);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	430
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	431 buf_setpos(ses.writepayload, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	432
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	433 #ifndef DISABLE_ZLIB
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	434 /* compression */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	435 if (ses.keys->trans_algo_comp == DROPBEAR_COMP_ZLIB) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	436 buf_compress(clearwritebuf, ses.writepayload, ses.writepayload->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	437 } else
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	438 #endif
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	439 {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	440 memcpy(buf_getwriteptr(clearwritebuf, ses.writepayload->len),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	441 buf_getptr(ses.writepayload, ses.writepayload->len),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	442 ses.writepayload->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	443 buf_incrwritepos(clearwritebuf, ses.writepayload->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	444 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	445
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	446 /* finished with payload */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	447 buf_burn(ses.writepayload); /* XXX This is probably a good idea, and isn't
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	448 _that_ likely to hurt performance too badly.
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	449 Buffers can have cleartext passwords etc, or
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	450 other sensitive data */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	451 buf_setpos(ses.writepayload, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	452 buf_setlen(ses.writepayload, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	453
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	454 /* length of padding - packet length must be a multiple of blocksize,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	455 * with a minimum of 4 bytes of padding */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	456 padlen = blocksize - (clearwritebuf->len) % blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	457 if (padlen < 4) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	458 padlen += blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	459 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	460 /* check for min packet length */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	461 if (clearwritebuf->len + padlen < MIN_PACKET_LEN) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	462 padlen += blocksize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	463 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	464
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	465 buf_setpos(clearwritebuf, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	466 /* packet length excluding the packetlength uint32 */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	467 buf_putint(clearwritebuf, clearwritebuf->len + padlen - 4);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	468
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	469 /* padding len */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	470 buf_putbyte(clearwritebuf, padlen);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	471 /* actual padding */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	472 buf_setpos(clearwritebuf, clearwritebuf->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	473 buf_incrlen(clearwritebuf, padlen);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	474 genrandom(buf_getptr(clearwritebuf, padlen), padlen);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	475
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	476 /* do the actual encryption */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	477 buf_setpos(clearwritebuf, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	478 /* create a new writebuffer, this is freed when it has been put on the
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	479 * wire by writepacket() */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	480 writebuf = buf_new(clearwritebuf->len + macsize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	481
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	482 if (ses.keys->trans_algo_crypt->cipherdesc == NULL) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	483 /* copy it */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	484 memcpy(buf_getwriteptr(writebuf, clearwritebuf->len),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	485 buf_getptr(clearwritebuf, clearwritebuf->len),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	486 clearwritebuf->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	487 buf_incrwritepos(writebuf, clearwritebuf->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	488 } else {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	489 /* encrypt it */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	490 while (clearwritebuf->pos < clearwritebuf->len) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	491 if (cbc_encrypt(buf_getptr(clearwritebuf, blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	492 buf_getwriteptr(writebuf, blocksize),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	493 &ses.keys->trans_symmetric_struct) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	494 dropbear_exit("error encrypting");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	495 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	496 buf_incrpos(clearwritebuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	497 buf_incrwritepos(writebuf, blocksize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	498 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	499 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	500
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	501 /* now add a hmac and we're done */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	502 writemac(writebuf, clearwritebuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	503
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	504 /* clearwritebuf is finished with */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	505 buf_free(clearwritebuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	506
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	507 /* enqueue the packet for sending */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	508 buf_setpos(writebuf, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	509 enqueue(&ses.writequeue, (void*)writebuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	510
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	511 /* Update counts */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	512 ses.kexstate.datatrans += writebuf->len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	513 ses.transseq++;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	514
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	515 TRACE(("leave encrypt_packet()"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	516 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	517
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	518
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	519 /* Create the packet mac, and append H(seqno\|clearbuf) to the output */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	520 static void writemac(buffer * outputbuffer, buffer * clearwritebuf) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	521
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	522 int macsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	523 unsigned char seqbuf[4];
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	524 unsigned long hashsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	525 hmac_state hmac;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	526
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	527 TRACE(("enter writemac"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	528
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	529 macsize = ses.keys->trans_algo_mac->hashsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	530
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	531 if (macsize > 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	532 /* calculate the mac */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	533 if (hmac_init(&hmac,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	534 find_hash(ses.keys->trans_algo_mac->hashdesc->name),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	535 ses.keys->transmackey,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	536 ses.keys->trans_algo_mac->keysize) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	537 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	538 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	539
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	540 /* sequence number */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	541 STORE32H(ses.transseq, seqbuf);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	542 if (hmac_process(&hmac, seqbuf, 4) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	543 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	544 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	545
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	546 /* the actual contents */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	547 buf_setpos(clearwritebuf, 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	548 if (hmac_process(&hmac,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	549 buf_getptr(clearwritebuf,
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	550 clearwritebuf->len),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	551 clearwritebuf->len) != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	552 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	553 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	554
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	555 hashsize = macsize;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	556 if (hmac_done(&hmac, buf_getwriteptr(outputbuffer, macsize), &hashsize)
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	557 != CRYPT_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	558 dropbear_exit("HMAC error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	559 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	560 buf_incrwritepos(outputbuffer, macsize);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	561 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	562 TRACE(("leave writemac"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	563 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	564
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	565 #ifndef DISABLE_ZLIB
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	566 /* compresses len bytes from src, outputting to dest (starting from the
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	567 * respective current positions. */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	568 static void buf_compress(buffer * dest, buffer * src, unsigned int len) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	569
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	570 unsigned int endpos = src->pos + len;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	571 int result;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	572
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	573 TRACE(("enter buf_compress"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	574
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	575 while (1) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	576
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	577 ses.keys->trans_zstream->avail_in = endpos - src->pos;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	578 ses.keys->trans_zstream->next_in =
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	579 buf_getptr(src, ses.keys->trans_zstream->avail_in);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	580
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	581 ses.keys->trans_zstream->avail_out = dest->size - dest->pos;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	582 ses.keys->trans_zstream->next_out =
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	583 buf_getwriteptr(dest, ses.keys->trans_zstream->avail_out);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	584
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	585 result = deflate(ses.keys->trans_zstream, Z_SYNC_FLUSH);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	586
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	587 buf_setpos(src, endpos - ses.keys->trans_zstream->avail_in);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	588 buf_setlen(dest, dest->size - ses.keys->trans_zstream->avail_out);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	589 buf_setpos(dest, dest->len);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	590
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	591 if (result != Z_OK) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	592 dropbear_exit("zlib error");
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	593 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	594
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	595 if (ses.keys->trans_zstream->avail_in == 0) {
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	596 break;
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	597 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	598
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	599 assert(ses.keys->trans_zstream->avail_out == 0);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	600
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	601 /* the buffer has been filled, we must extend. This only happens in
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	602 * unusual circumstances where the data grows in size after deflate(),
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	603 * but it is possible */
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	604 buf_resize(dest, dest->size + ZLIB_COMPRESS_INCR);
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	605
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	606 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	607 TRACE(("leave buf_compress"));
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	608 }
08da099e8337 - Rename common-packet.c to packet.c Matt Johnston <matt@ucc.asn.au> parents: diff changeset	609 #endif

Mercurial > dropbear

annotate packet.c @ 45:9ee8996a375f