/**
* trie_match
* @t: trie
* @px: prefix address
* @plen: prefix length
*
* Tries to find a matching prefix pattern in the trie such that
* prefix @px/@plen matches that prefix pattern. Returns 1 if there
* is such prefix pattern in the trie.
*/
int
trie_match_prefix(struct f_trie *t, ip_addr px, int plen)
{
ip_addr pmask = ipa_mkmask(plen);
ip_addr paddr = ipa_and(px, pmask);
if (plen == 0)
return t->zero;
int plentest = plen - 1;
struct f_trie_node *n = &t->root;
while(n)
{
ip_addr cmask = ipa_and(n->mask, pmask);
/* We are out of path */
if (ipa_compare(ipa_and(paddr, cmask), ipa_and(n->addr, cmask)))
return 0;
/* Check accept mask */
if (ipa_getbit(n->accept, plentest))
return 1;
/* We finished trie walk and still no match */
if (plen <= n->plen)
return 0;
/* Choose children */
n = n->c[(ipa_getbit(paddr, n->plen)) ? 1 : 0];
}
return 0;
}
static void
scan_ifs(struct ifreq *r, int cnt)
{
struct iface i, *pi;
struct ifa a;
char *err, *colon;
unsigned fl;
ip_addr netmask;
int l, scope;
sockaddr *sa;
if_start_update();
for (cnt /= sizeof(struct ifreq); cnt; cnt--, r++)
{
int sec = 0;
bzero(&i, sizeof(i));
bzero(&a, sizeof(a));
if (colon = strchr(r->ifr_name, ':'))
{
/* It's an alias -- let's interpret it as a secondary interface address */
sec = 1;
*colon = 0;
}
strncpy(i.name, r->ifr_name, sizeof(i.name) - 1);
if(ioctl(if_scan_sock, SIOCGIFADDR,r)<0) continue;
get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.ip, NULL, 1);
if (ipa_nonzero(a.ip))
{
l = ipa_classify(a.ip);
if (l < 0 || !(l & IADDR_HOST))
{
log(L_ERR "%s: Invalid interface address", i.name);
a.ip = IPA_NONE;
}
else
{
a.scope = l & IADDR_SCOPE_MASK;
if (a.scope == SCOPE_HOST)
i.flags |= IF_LOOPBACK | IF_IGNORE;
}
}
if (ioctl(if_scan_sock, SIOCGIFFLAGS, r) < 0)
{
err = "SIOCGIFFLAGS";
faulty:
log(L_ERR "%s(%s): %m", err, i.name);
bad:
i.flags = (i.flags & ~IF_LINK_UP) | IF_ADMIN_DOWN;
continue;
}
fl = r->ifr_flags;
if (fl & IFF_UP)
i.flags |= IF_LINK_UP;
if (ioctl(if_scan_sock, SIOCGIFNETMASK, r) < 0)
{ err = "SIOCGIFNETMASK"; goto faulty; }
get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &netmask, NULL, 0);
l = ipa_mklen(netmask);
if (l < 0 || l == 31)
{
log(L_ERR "%s: Invalid netmask (%x)", i.name, netmask);
goto bad;
}
a.pxlen = l;
if (fl & IFF_POINTOPOINT)
{
a.flags |= IA_UNNUMBERED;
if (ioctl(if_scan_sock, SIOCGIFDSTADDR, r) < 0)
{ err = "SIOCGIFDSTADDR"; goto faulty; }
get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.opposite, NULL, 1);
a.prefix = a.opposite;
a.pxlen = BITS_PER_IP_ADDRESS;
}
else
a.prefix = ipa_and(a.ip, ipa_mkmask(a.pxlen));
if (fl & IFF_LOOPBACK)
i.flags |= IF_LOOPBACK | IF_IGNORE;
if (1
#ifndef CONFIG_ALL_MULTICAST
&& (fl & IFF_MULTICAST)
#endif
#ifndef CONFIG_UNNUM_MULTICAST
&& !(a.flags & IA_UNNUMBERED)
#endif
)
i.flags |= IF_MULTICAST;
scope = ipa_classify(a.ip);
if (scope < 0)
{
log(L_ERR "%s: Invalid address", i.name);
goto bad;
}
a.scope = scope & IADDR_SCOPE_MASK;
if (a.pxlen < 32)
{
a.brd = ipa_or(a.prefix, ipa_not(ipa_mkmask(a.pxlen)));
if (ipa_equal(a.ip, a.prefix) || ipa_equal(a.ip, a.brd))
{
log(L_ERR "%s: Using network or broadcast address for interface", i.name);
goto bad;
}
if (fl & IFF_BROADCAST)
i.flags |= IF_BROADCAST;
if (a.pxlen < 30)
i.flags |= IF_MULTIACCESS;
else
a.opposite = ipa_opposite(a.ip, a.pxlen);
}
else
a.brd = a.opposite;
a.scope = SCOPE_UNIVERSE;
if (ioctl(if_scan_sock, SIOCGIFMTU, r) < 0)
{ err = "SIOCGIFMTU"; goto faulty; }
i.mtu = r->ifr_mtu;
#ifdef SIOCGIFINDEX
if (ioctl(if_scan_sock, SIOCGIFINDEX, r) >= 0)
i.index = r->ifr_ifindex;
else if (errno != EINVAL)
DBG("SIOCGIFINDEX failed: %m\n");
else /* defined, but not supported by the kernel */
#endif
/*
* The kernel doesn't give us real ifindices, but we still need them
* at least for OSPF unnumbered links. So let's make them up ourselves.
*/
if (pi = if_find_by_name(i.name))
i.index = pi->index;
else
{
static int if_index_counter = 1;
i.index = if_index_counter++;
}
pi = NULL;
if (sec)
{
a.flags |= IA_SECONDARY;
pi = if_find_by_index(i.index);
}
if (!pi)
pi = if_update(&i);
a.iface = pi;
ifa_update(&a);
}
if_end_update();
}
void
trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h)
{
if (l == 0)
t->zero = 1;
else
l--;
if (h < plen)
plen = h;
ip_addr amask = ipa_xor(ipa_mkmask(l), ipa_mkmask(h));
ip_addr pmask = ipa_mkmask(plen);
ip_addr paddr = ipa_and(px, pmask);
struct f_trie_node *o = NULL;
struct f_trie_node *n = &t->root;
while(n)
{
ip_addr cmask = ipa_and(n->mask, pmask);
if (ipa_compare(ipa_and(paddr, cmask), ipa_and(n->addr, cmask)))
{
/* We are out of path - we have to add branching node 'b'
between node 'o' and node 'n', and attach new node 'a'
as the other child of 'b'. */
int blen = ipa_pxlen(paddr, n->addr);
ip_addr bmask = ipa_mkmask(blen);
ip_addr baddr = ipa_and(px, bmask);
/* Merge accept masks from children to get accept mask for node 'b' */
ip_addr baccm = ipa_and(ipa_or(amask, n->accept), bmask);
struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask);
struct f_trie_node *b = new_node(t, blen, baddr, bmask, baccm);
attach_node(o, b);
attach_node(b, n);
attach_node(b, a);
return;
}
if (plen < n->plen)
{
/* We add new node 'a' between node 'o' and node 'n' */
amask = ipa_or(amask, ipa_and(n->accept, pmask));
struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask);
attach_node(o, a);
attach_node(a, n);
return;
}
if (plen == n->plen)
{
/* We already found added node in trie. Just update accept mask */
n->accept = ipa_or(n->accept, amask);
return;
}
/* Update accept mask part M2 and go deeper */
n->accept = ipa_or(n->accept, ipa_and(amask, n->mask));
/* n->plen < plen and plen <= 32 (128) */
o = n;
n = n->c[ipa_getbit(paddr, n->plen) ? 1 : 0];
}
/* We add new tail node 'a' after node 'o' */
struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask);
attach_node(o, a);
}
