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/*
* BIRD -- OSPF
*
* (c) 1999-2000 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
void
htonlsah(struct ospf_lsa_header *h, struct ospf_lsa_header *n)
{
n->age=htons(h->age);
n->options=h->options;
n->type=h->type;
n->id=htonl(h->id);
n->rt=htonl(h->rt);
n->sn=htonl(h->sn);
n->checksum=htons(h->checksum);
n->length=htons(h->length);
};
void
ntohlsah(struct ospf_lsa_header *n, struct ospf_lsa_header *h)
{
h->age=ntohs(n->age);
h->options=n->options;
h->type=n->type;
h->id=ntohl(n->id);
h->rt=ntohl(n->rt);
h->sn=ntohl(n->sn);
h->checksum=ntohs(n->checksum);
h->length=ntohs(n->length);
};
void
htonlsab(void *h, void *n, u8 type, u16 len)
{
unsigned int i;
switch(type)
{
case LSA_T_RT:
{
struct ospf_lsa_rt *hrt, *nrt;
struct ospf_lsa_rt_link *hrtl,*nrtl;
u16 links;
nrt=n;
hrt=h;
links=hrt->links;
nrt->VEB=hrt->VEB;
nrt->padding=0;
nrt->links=htons(hrt->links);
nrtl=(struct ospf_lsa_rt_link *)(nrt+1);
hrtl=(struct ospf_lsa_rt_link *)(hrt+1);
for(i=0;i<links;i++)
{
(nrtl+i)->id=htonl((hrtl+i)->id);
(nrtl+i)->data=htonl((hrtl+i)->data);
(nrtl+i)->type=(hrtl+i)->type;
(nrtl+i)->notos=(hrtl+i)->notos;
(nrtl+i)->metric=htons((hrtl+i)->metric);
}
break;
}
case LSA_T_NET:
{
u32 *hid,*nid;
nid=n;
hid=h;
for(i=0;i<(len/sizeof(u32));i++)
{
*(nid+i)=htonl(*(hid+i));
}
break;
}
case LSA_T_SUM_NET:
case LSA_T_SUM_RT:
{
struct ospf_lsa_summ *hs, *ns;
struct ospf_lsa_summ_net *hn, *nn;
hs=h;
ns=n;
ns->netmask=htonl(hs->netmask);
hn=(struct ospf_lsa_summ_net *)(hs+1);
nn=(struct ospf_lsa_summ_net *)(ns+1);
for(i=0;i<((len-sizeof(struct ospf_lsa_summ))/
sizeof(struct ospf_lsa_summ_net));i++)
{
(nn+i)->tos=(hn+i)->tos;
(nn+i)->metric=htons((hn+i)->metric);
(nn+i)->padding=0;
}
break;
}
case LSA_T_EXT:
{
struct ospf_lsa_ext *he, *ne;
struct ospf_lsa_ext_tos *ht, *nt;
he=h;
ne=n;
ne->netmask=htonl(he->netmask);
ht=(struct ospf_lsa_ext_tos *)(he+1);
nt=(struct ospf_lsa_ext_tos *)(ne+1);
for(i=0;i<((len-sizeof(struct ospf_lsa_ext))/
sizeof(struct ospf_lsa_ext_tos));i++)
{
(nt+i)->etos=(ht+i)->etos;
(nt+i)->padding=0;
(nt+i)->metric=htons((ht+i)->metric);
(nt+i)->fwaddr=htonl((ht+i)->fwaddr);
(nt+i)->tag=htonl((ht+i)->tag);
}
break;
}
default: die("(hton): Unknown LSA\n");
}
};
void
ntohlsab(void *n, void *h, u8 type, u16 len)
{
unsigned int i;
switch(type)
{
case LSA_T_RT:
{
struct ospf_lsa_rt *hrt, *nrt;
struct ospf_lsa_rt_link *hrtl,*nrtl;
u16 links;
nrt=n;
hrt=h;
hrt->VEB=nrt->VEB;
hrt->padding=0;
links=hrt->links=ntohs(nrt->links);
nrtl=(struct ospf_lsa_rt_link *)(nrt+1);
hrtl=(struct ospf_lsa_rt_link *)(hrt+1);
for(i=0;i<links;i++)
{
(hrtl+i)->id=ntohl((nrtl+i)->id);
(hrtl+i)->data=ntohl((nrtl+i)->data);
(hrtl+i)->type=(nrtl+i)->type;
(hrtl+i)->notos=(nrtl+i)->notos;
(hrtl+i)->metric=ntohs((nrtl+i)->metric);
}
break;
}
case LSA_T_NET:
{
u32 *hid,*nid;
hid=h;
nid=n;
for(i=0;i<(len/sizeof(u32));i++)
{
*(hid+i)=ntohl(*(nid+i));
}
break;
}
case LSA_T_SUM_NET:
case LSA_T_SUM_RT:
{
struct ospf_lsa_summ *hs, *ns;
struct ospf_lsa_summ_net *hn, *nn;
hs=h;
ns=n;
hs->netmask=ntohl(ns->netmask);
hn=(struct ospf_lsa_summ_net *)(hs+1);
nn=(struct ospf_lsa_summ_net *)(ns+1);
for(i=0;i<((len-sizeof(struct ospf_lsa_summ))/
sizeof(struct ospf_lsa_summ_net));i++)
{
(hn+i)->tos=(nn+i)->tos;
(hn+i)->metric=ntohs((nn+i)->metric);
(hn+i)->padding=0;
}
break;
}
case LSA_T_EXT:
{
struct ospf_lsa_ext *he, *ne;
struct ospf_lsa_ext_tos *ht, *nt;
he=h;
ne=n;
he->netmask=ntohl(ne->netmask);
ht=(struct ospf_lsa_ext_tos *)(he+1);
nt=(struct ospf_lsa_ext_tos *)(ne+1);
for(i=0;i<((len-sizeof(struct ospf_lsa_ext))/
sizeof(struct ospf_lsa_ext_tos));i++)
{
(ht+i)->etos=(nt+i)->etos;
(ht+i)->padding=0;
(ht+i)->metric=ntohs((nt+i)->metric);
(ht+i)->fwaddr=ntohl((nt+i)->fwaddr);
(ht+i)->tag=ntohl((nt+i)->tag);
}
break;
}
default: die("(ntoh): Unknown LSA\n");
}
};
#define MODX 4102 /* larges signed value without overflow */
/* Fletcher Checksum -- Refer to RFC1008. */
#define MODX 4102
#define LSA_CHECKSUM_OFFSET 15
/* FIXME This is VERY uneficient, I have huge endianity problems */
void
lsasum_calculate(struct ospf_lsa_header *h,void *body,struct proto_ospf *po)
{
u8 *sp, *ep, *p, *q, *b;
int c0 = 0, c1 = 0;
int x, y;
u16 length;
h->checksum = 0;
b=body;
length = h->length-2;
sp = (char *) &h->options;
htonlsah(h,h);
htonlsab(b,b,h->type,length+2);
for (ep = sp + length; sp < ep; sp = q)
{
q = sp + MODX;
if (q > ep)
q = ep;
for (p = sp; p < q; p++)
{
if(p<(u8 *)(h+1))
{
c0 += *p;
/*DBG("XXXXXX: %u\t%u\n", p-sp, *p);*/
}
else
{
c0 += *(b+(p-sp)-sizeof(struct ospf_lsa_header)+2);
/*DBG("YYYYYY: %u\t%u\n", p-sp,*(b+(p-sp)-sizeof(struct ospf_lsa_header)+2));*/
}
c1 += c0;
}
c0 %= 255;
c1 %= 255;
}
x = ((length - LSA_CHECKSUM_OFFSET) * c0 - c1) % 255;
if (x <= 0)
x += 255;
y = 510 - c0 - x;
if (y > 255)
y -= 255;
h->checksum = x + (y << 8);
ntohlsah(h,h);
ntohlsab(b,b,h->type,length+2);
}
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