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Further restructuring

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[originally from svn r657]
This commit is contained in:
Simon Tatham 2000-09-29 15:56:33 +00:00
parent bfec52c1c9
commit a4a9ccc70b
1 changed files with 41 additions and 36 deletions
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77
ssh.c
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@ -263,6 +263,13 @@ static struct rdpkt1_state_tag {
int chunk;
} rdpkt1_state;
static struct rdpkt2_state_tag {
long len, pad, payload, packetlen, maclen;
int i;
int cipherblk;
unsigned long incoming_sequence;
} rdpkt2_state;
static int ssh_channelcmp(void *av, void *bv) {
struct ssh_channel *a = (struct ssh_channel *)av;
struct ssh_channel *b = (struct ssh_channel *)bv;
@ -425,29 +432,24 @@ next_packet:
static int ssh2_rdpkt(unsigned char **data, int *datalen)
{
static long len, pad, payload, packetlen, maclen;
static int i;
static int cipherblk;
static unsigned long incoming_sequence = 0;
struct rdpkt2_state_tag *st = &rdpkt2_state;
crBegin;
next_packet:
pktin.type = 0;
pktin.length = 0;
if (cipher)
cipherblk = cipher->blksize;
if (sccipher)
st->cipherblk = sccipher->blksize;
else
cipherblk = 8;
if (cipherblk < 8)
cipherblk = 8;
st->cipherblk = 8;
if (st->cipherblk < 8)
st->cipherblk = 8;
if (pktin.maxlen < cipherblk) {
pktin.maxlen = cipherblk;
pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) :
realloc(pktin.data, cipherblk+APIEXTRA));
if (pktin.maxlen < st->cipherblk) {
pktin.maxlen = st->cipherblk;
pktin.data = (pktin.data == NULL ? malloc(st->cipherblk+APIEXTRA) :
realloc(pktin.data, st->cipherblk+APIEXTRA));
if (!pktin.data)
fatalbox("Out of memory");
}
@ -456,10 +458,10 @@ next_packet:
* Acquire and decrypt the first block of the packet. This will
* contain the length and padding details.
*/
for (i = len = 0; i < cipherblk; i++) {
for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
while ((*datalen) == 0)
crReturn(cipherblk-i);
pktin.data[i] = *(*data)++;
crReturn(st->cipherblk-st->i);
pktin.data[st->i] = *(*data)++;
(*datalen)--;
}
#ifdef FWHACK
@ -468,32 +470,32 @@ next_packet:
}
#endif
if (sccipher)
sccipher->decrypt(pktin.data, cipherblk);
sccipher->decrypt(pktin.data, st->cipherblk);
/*
* Now get the length and padding figures.
*/
len = GET_32BIT(pktin.data);
pad = pktin.data[4];
st->len = GET_32BIT(pktin.data);
st->pad = pktin.data[4];
/*
* This enables us to deduce the payload length.
*/
payload = len - pad - 1;
st->payload = st->len - st->pad - 1;
pktin.length = payload + 5;
pktin.length = st->payload + 5;
/*
* So now we can work out the total packet length.
*/
packetlen = len + 4;
maclen = scmac ? scmac->len : 0;
st->packetlen = st->len + 4;
st->maclen = scmac ? scmac->len : 0;
/*
* Adjust memory allocation if packet is too big.
*/
if (pktin.maxlen < packetlen+maclen) {
pktin.maxlen = packetlen+maclen;
if (pktin.maxlen < st->packetlen+st->maclen) {
pktin.maxlen = st->packetlen+st->maclen;
pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
realloc(pktin.data, pktin.maxlen+APIEXTRA));
if (!pktin.data)
@ -503,31 +505,32 @@ next_packet:
/*
* Read and decrypt the remainder of the packet.
*/
for (i = cipherblk; i < packetlen + maclen; i++) {
for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) {
while ((*datalen) == 0)
crReturn(packetlen + maclen - i);
pktin.data[i] = *(*data)++;
crReturn(st->packetlen + st->maclen - st->i);
pktin.data[st->i] = *(*data)++;
(*datalen)--;
}
/* Decrypt everything _except_ the MAC. */
if (sccipher)
sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk);
sccipher->decrypt(pktin.data + st->cipherblk,
st->packetlen - st->cipherblk);
#if 0
debug(("Got packet len=%d pad=%d\r\n", len, pad));
for (i = 0; i < packetlen; i++)
debug((" %02x", (unsigned char)pktin.data[i]));
debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
for (st->i = 0; st->i < st->packetlen; st->i++)
debug((" %02x", (unsigned char)pktin.data[st->i]));
debug(("\r\n"));
#endif
/*
* Check the MAC.
*/
if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) {
if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) {
bombout(("Incorrect MAC received on packet"));
crReturn(0);
}
incoming_sequence++; /* whether or not we MACed */
st->incoming_sequence++; /* whether or not we MACed */
pktin.savedpos = 6;
pktin.type = pktin.data[5];
@ -1028,6 +1031,8 @@ static int do_ssh_init(void) {
break;
}
rdpkt2_state.incoming_sequence = 0;
*vsp = 0;
sprintf(vlog, "Server version: %s", vstring);
vlog[strcspn(vlog, "\r\n")] = '\0';