ppp: mppe: sanity error path rework

We are going to need sanity error path a little further, rework to be
able to use the sanity error path anywhere in decompressor.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sylvain Rochet 2015-04-26 20:40:52 +02:00 committed by David S. Miller
parent 73b5a6f2a7
commit 325301892a
1 changed files with 13 additions and 16 deletions

View File

@ -478,7 +478,6 @@ mppe_decompress(void *arg, unsigned char *ibuf, int isize, unsigned char *obuf,
struct blkcipher_desc desc = { .tfm = state->arc4 };
unsigned ccount;
int flushed = MPPE_BITS(ibuf) & MPPE_BIT_FLUSHED;
int sanity = 0;
struct scatterlist sg_in[1], sg_out[1];
if (isize <= PPP_HDRLEN + MPPE_OVHD) {
@ -514,31 +513,19 @@ mppe_decompress(void *arg, unsigned char *ibuf, int isize, unsigned char *obuf,
"mppe_decompress[%d]: ENCRYPTED bit not set!\n",
state->unit);
state->sanity_errors += 100;
sanity = 1;
goto sanity_error;
}
if (!state->stateful && !flushed) {
printk(KERN_DEBUG "mppe_decompress[%d]: FLUSHED bit not set in "
"stateless mode!\n", state->unit);
state->sanity_errors += 100;
sanity = 1;
goto sanity_error;
}
if (state->stateful && ((ccount & 0xff) == 0xff) && !flushed) {
printk(KERN_DEBUG "mppe_decompress[%d]: FLUSHED bit not set on "
"flag packet!\n", state->unit);
state->sanity_errors += 100;
sanity = 1;
}
if (sanity) {
if (state->sanity_errors < SANITY_MAX)
return DECOMP_ERROR;
else
/*
* Take LCP down if the peer is sending too many bogons.
* We don't want to do this for a single or just a few
* instances since it could just be due to packet corruption.
*/
return DECOMP_FATALERROR;
goto sanity_error;
}
/*
@ -649,6 +636,16 @@ mppe_decompress(void *arg, unsigned char *ibuf, int isize, unsigned char *obuf,
state->sanity_errors >>= 1;
return osize;
sanity_error:
if (state->sanity_errors < SANITY_MAX)
return DECOMP_ERROR;
else
/* Take LCP down if the peer is sending too many bogons.
* We don't want to do this for a single or just a few
* instances since it could just be due to packet corruption.
*/
return DECOMP_FATALERROR;
}
/*