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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* PIM for Quagga
* Copyright (C) 2008 Everton da Silva Marques
*/
#include <zebra.h>
#include "log.h"
#include "prefix.h"
#include "plist.h"
#include "plist_int.h"
#include "pimd.h"
#include "pim_instance.h"
#include "pim_util.h"
/*
RFC 3376: 4.1.7. QQIC (Querier's Query Interval Code)
If QQIC < 128, QQI = QQIC
If QQIC >= 128, QQI = (mant | 0x10) << (exp + 3)
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|1| exp | mant |
+-+-+-+-+-+-+-+-+
Since exp=0..7 then (exp+3)=3..10, then QQI has
one of the following bit patterns:
exp=0: QQI = 0000.0000.1MMM.M000
exp=1: QQI = 0000.0001.MMMM.0000
...
exp=6: QQI = 001M.MMM0.0000.0000
exp=7: QQI = 01MM.MM00.0000.0000
--------- ---------
0x4 0x0 0x0 0x0
*/
uint8_t igmp_msg_encode16to8(uint16_t value)
{
uint8_t code;
if (value < 128) {
code = value;
} else {
uint16_t mask = 0x4000;
uint8_t exp;
uint16_t mant;
for (exp = 7; exp > 0; --exp) {
if (mask & value)
break;
mask >>= 1;
}
mant = 0x000F & (value >> (exp + 3));
code = ((uint8_t)1 << 7) | ((uint8_t)exp << 4) | (uint8_t)mant;
}
return code;
}
/*
RFC 3376: 4.1.7. QQIC (Querier's Query Interval Code)
If QQIC < 128, QQI = QQIC
If QQIC >= 128, QQI = (mant | 0x10) << (exp + 3)
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|1| exp | mant |
+-+-+-+-+-+-+-+-+
*/
uint16_t igmp_msg_decode8to16(uint8_t code)
{
uint16_t value;
if (code < 128) {
value = code;
} else {
uint16_t mant = (code & 0x0F);
uint8_t exp = (code & 0x70) >> 4;
value = (mant | 0x10) << (exp + 3);
}
return value;
}
void pim_pkt_dump(const char *label, const uint8_t *buf, int size)
{
zlog_debug("%s: pkt dump size=%d", label, size);
zlog_hexdump(buf, size);
}
int pim_is_group_224_0_0_0_24(struct in_addr group_addr)
{
static int first = 1;
static struct prefix group_224;
struct prefix group;
if (first) {
if (!str2prefix("224.0.0.0/24", &group_224))
return 0;
first = 0;
}
group.family = AF_INET;
group.u.prefix4 = group_addr;
group.prefixlen = IPV4_MAX_BITLEN;
return prefix_match(&group_224, &group);
}
int pim_is_group_224_4(struct in_addr group_addr)
{
static int first = 1;
static struct prefix group_all;
struct prefix group;
if (first) {
if (!str2prefix("224.0.0.0/4", &group_all))
return 0;
first = 0;
}
group.family = AF_INET;
group.u.prefix4 = group_addr;
group.prefixlen = IPV4_MAX_BITLEN;
return prefix_match(&group_all, &group);
}
static bool pim_cisco_match(const struct filter *filter, const struct in_addr *source,
const struct in_addr *group)
{
const struct filter_cisco *cfilter = &filter->u.cfilter;
uint32_t source_addr;
uint32_t group_addr;
group_addr = group->s_addr & ~cfilter->mask_mask.s_addr;
if (cfilter->extended) {
source_addr = source->s_addr & ~cfilter->addr_mask.s_addr;
if (group_addr == cfilter->mask.s_addr && source_addr == cfilter->addr.s_addr)
return true;
} else if (group_addr == cfilter->addr.s_addr)
return true;
return false;
}
enum filter_type pim_access_list_apply(struct access_list *access, const struct in_addr *source,
const struct in_addr *group)
{
struct filter *filter;
struct prefix group_prefix = {};
if (access == NULL)
return FILTER_DENY;
for (filter = access->head; filter; filter = filter->next) {
if (filter->cisco) {
if (pim_cisco_match(filter, source, group))
return filter->type;
}
}
group_prefix.family = AF_INET;
group_prefix.prefixlen = IPV4_MAX_BITLEN;
group_prefix.u.prefix4.s_addr = group->s_addr;
return access_list_apply(access, &group_prefix);
}
bool pim_is_group_filtered(struct pim_interface *pim_ifp, pim_addr *grp, pim_addr *src)
{
bool is_filtered = false;
#if PIM_IPV == 4
struct prefix grp_pfx = {};
pim_addr any_src = PIMADDR_ANY;
if (!pim_ifp->boundary_oil_plist && !pim_ifp->boundary_acl)
return false;
pim_addr_to_prefix(&grp_pfx, *grp);
/* Filter if either group or (S,G) are denied */
if (pim_ifp->boundary_oil_plist) {
is_filtered = prefix_list_apply_ext(pim_ifp->boundary_oil_plist, NULL, &grp_pfx,
true) == PREFIX_DENY;
if (is_filtered && PIM_DEBUG_EVENTS) {
zlog_debug("Filtering group %pI4 per prefix-list %s", grp,
pim_ifp->boundary_oil_plist->name);
}
}
if (!is_filtered && pim_ifp->boundary_acl) {
/* If src not provided, set to "any" (*)? */
if (!src)
src = &any_src;
/* S,G filtering using extended access-list syntax */
is_filtered = pim_access_list_apply(pim_ifp->boundary_acl, src, grp) == FILTER_DENY;
if (is_filtered && PIM_DEBUG_EVENTS) {
if (pim_addr_is_any(*src)) {
zlog_debug("Filtering (S,G)=(*, %pI4) per access-list %s", grp,
pim_ifp->boundary_acl->name);
} else {
zlog_debug("Filtering (S,G)=(%pI4, %pI4) per access-list %s", src,
grp, pim_ifp->boundary_acl->name);
}
}
}
#endif
return is_filtered;
}
/* This function returns all multicast group */
void pim_get_all_mcast_group(struct prefix *prefix)
{
memset(prefix, 0, sizeof(*prefix));
#if PIM_IPV == 4
/* Precomputed version of: `str2prefix("224.0.0.0/4", prefix);` */
prefix->family = AF_INET;
prefix->prefixlen = 4;
prefix->u.prefix4.s_addr = htonl(0xe0000000);
#else
/* Precomputed version of: `str2prefix("FF00::0/8", prefix)` */
prefix->family = AF_INET6;
prefix->prefixlen = 8;
prefix->u.prefix6.s6_addr[0] = 0xff;
#endif
}
bool pim_addr_is_multicast(pim_addr addr)
{
#if PIM_IPV == 4
if (IN_MULTICAST(ntohl(addr.s_addr)))
return true;
#else
if (IN6_IS_ADDR_MULTICAST(&addr))
return true;
#endif
return false;
}
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