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ofono
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Code Issues Releases Activity

Check FCS while unstuffing the byte stream

This commit is contained in:
Marcel Holtmann 2010-04-01 20:18:49 -07:00
parent dabac98cb4
commit cdc1e3c31b
1 changed files with 11 additions and 10 deletions
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21
gatchat/ppp.c
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@ -217,9 +217,8 @@ static void ppp_recv(GAtPPP *ppp, struct frame_buffer *frame)
static struct frame_buffer *ppp_decode(GAtPPP *ppp, guint8 *frame)
{
guint8 *data;
guint pos = 0;
int i = 0;
int len;
guint pos;
int i;
guint16 fcs;
struct frame_buffer *fb;
@ -229,7 +228,10 @@ static struct frame_buffer *ppp_decode(GAtPPP *ppp, guint8 *frame)
data = fb->bytes;
/* skip the first flag char */
pos++;
pos = 1;
fcs = PPPINITFCS16;
i = 0;
/* TBD - how to deal with recv_accm */
while (frame[pos] != PPP_FLAG_SEQ) {
@ -240,21 +242,20 @@ static struct frame_buffer *ppp_decode(GAtPPP *ppp, guint8 *frame)
data[i] = frame[pos] ^ 0x20;
} else
data[i] = frame[pos];
fcs = ppp_fcs(fcs, data[i]);
i++; pos++;
}
len = i;
fb->len = len;
fb->len = i;
/* see if we have a good FCS */
fcs = PPPINITFCS16;
for (i = 0; i < len; i++)
fcs = ppp_fcs(fcs, data[i]);
if (fcs != PPPGOODFCS16) {
g_free(fb);
return NULL;
}
return fb;
}