mirror of
https://gitlab.nic.cz/labs/bird.git
synced 2024-11-17 08:38:42 +00:00
Multipath support for linux kernel protocol.
This commit is contained in:
Ondrej Zajicek
parent
57c574d82a
commit
32b4972834
@ -238,37 +238,143 @@ nl_parse_attrs(struct rtattr *a, struct rtattr **k, int ksize)
|
||||
return 1;
|
||||
}
|
||||
|
||||
static void
|
||||
nl_add_attr_u32(struct nlmsghdr *h, unsigned maxsize, int code, u32 data)
|
||||
void
|
||||
nl_add_attr(struct nlmsghdr *h, unsigned bufsize, unsigned code,
|
||||
void *data, unsigned dlen)
|
||||
{
|
||||
unsigned len = RTA_LENGTH(4);
|
||||
unsigned len = RTA_LENGTH(dlen);
|
||||
unsigned pos = NLMSG_ALIGN(h->nlmsg_len);
|
||||
struct rtattr *a;
|
||||
|
||||
if (NLMSG_ALIGN(h->nlmsg_len) + len > maxsize)
|
||||
bug("nl_add_attr32: packet buffer overflow");
|
||||
a = (struct rtattr *)((char *)h + NLMSG_ALIGN(h->nlmsg_len));
|
||||
if (pos + len > bufsize)
|
||||
bug("nl_add_attr: packet buffer overflow");
|
||||
a = (struct rtattr *)((char *)h + pos);
|
||||
a->rta_type = code;
|
||||
a->rta_len = len;
|
||||
memcpy(RTA_DATA(a), &data, 4);
|
||||
h->nlmsg_len = NLMSG_ALIGN(h->nlmsg_len) + len;
|
||||
h->nlmsg_len = pos + len;
|
||||
memcpy(RTA_DATA(a), data, dlen);
|
||||
}
|
||||
|
||||
static void
|
||||
nl_add_attr_ipa(struct nlmsghdr *h, unsigned maxsize, int code, ip_addr ipa)
|
||||
static inline void
|
||||
nl_add_attr_u32(struct nlmsghdr *h, unsigned bufsize, int code, u32 data)
|
||||
{
|
||||
unsigned len = RTA_LENGTH(sizeof(ipa));
|
||||
struct rtattr *a;
|
||||
nl_add_attr(h, bufsize, code, &data, 4);
|
||||
}
|
||||
|
||||
if (NLMSG_ALIGN(h->nlmsg_len) + len > maxsize)
|
||||
bug("nl_add_attr_ipa: packet buffer overflow");
|
||||
a = (struct rtattr *)((char *)h + NLMSG_ALIGN(h->nlmsg_len));
|
||||
a->rta_type = code;
|
||||
a->rta_len = len;
|
||||
static inline void
|
||||
nl_add_attr_ipa(struct nlmsghdr *h, unsigned bufsize, int code, ip_addr ipa)
|
||||
{
|
||||
ipa_hton(ipa);
|
||||
memcpy(RTA_DATA(a), &ipa, sizeof(ipa));
|
||||
h->nlmsg_len = NLMSG_ALIGN(h->nlmsg_len) + len;
|
||||
nl_add_attr(h, bufsize, code, &ipa, sizeof(ipa));
|
||||
}
|
||||
|
||||
#define RTNH_SIZE (sizeof(struct rtnexthop) + sizeof(struct rtattr) + sizeof(ip_addr))
|
||||
|
||||
static inline void
|
||||
add_mpnexthop(char *buf, ip_addr ipa, unsigned iface, unsigned char weight)
|
||||
{
|
||||
struct rtnexthop *nh = (void *) buf;
|
||||
struct rtattr *rt = (void *) (buf + sizeof(*nh));
|
||||
nh->rtnh_len = RTNH_SIZE;
|
||||
nh->rtnh_flags = 0;
|
||||
nh->rtnh_hops = weight;
|
||||
nh->rtnh_ifindex = iface;
|
||||
rt->rta_len = sizeof(*rt) + sizeof(ipa);
|
||||
rt->rta_type = RTA_GATEWAY;
|
||||
ipa_hton(ipa);
|
||||
memcpy(buf + sizeof(*nh) + sizeof(*rt), &ipa, sizeof(ipa));
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
nl_add_multipath(struct nlmsghdr *h, unsigned bufsize, struct mpnh *nh)
|
||||
{
|
||||
unsigned len = sizeof(struct rtattr);
|
||||
unsigned pos = NLMSG_ALIGN(h->nlmsg_len);
|
||||
char *buf = (char *)h + pos;
|
||||
struct rtattr *rt = (void *) buf;
|
||||
buf += len;
|
||||
|
||||
for (; nh; nh = nh->next)
|
||||
{
|
||||
len += RTNH_SIZE;
|
||||
if (pos + len > bufsize)
|
||||
bug("nl_add_multipath: packet buffer overflow");
|
||||
|
||||
add_mpnexthop(buf, nh->gw, nh->iface->index, nh->weight);
|
||||
buf += RTNH_SIZE;
|
||||
}
|
||||
|
||||
rt->rta_type = RTA_MULTIPATH;
|
||||
rt->rta_len = len;
|
||||
h->nlmsg_len = pos + len;
|
||||
}
|
||||
|
||||
|
||||
static struct mpnh *
|
||||
nl_parse_multipath(struct krt_proto *p, struct rtattr *ra)
|
||||
{
|
||||
/* Temporary buffer for multicast nexthops */
|
||||
static struct mpnh *nh_buffer;
|
||||
static int nh_buf_size; /* in number of structures */
|
||||
static int nh_buf_used;
|
||||
|
||||
struct rtattr *a[RTA_CACHEINFO+1];
|
||||
struct rtnexthop *nh = RTA_DATA(ra);
|
||||
struct mpnh *rv, *first, **last;
|
||||
int len = RTA_PAYLOAD(ra);
|
||||
|
||||
first = NULL;
|
||||
last = &first;
|
||||
nh_buf_used = 0;
|
||||
|
||||
while (len)
|
||||
{
|
||||
/* Use RTNH_OK(nh,len) ?? */
|
||||
if ((len < sizeof(*nh)) || (len < nh->rtnh_len))
|
||||
return NULL;
|
||||
|
||||
if (nh_buf_used == nh_buf_size)
|
||||
{
|
||||
nh_buf_size = nh_buf_size ? (nh_buf_size * 2) : 4;
|
||||
nh_buffer = xrealloc(nh_buffer, nh_buf_size * sizeof(struct mpnh));
|
||||
}
|
||||
*last = rv = nh_buffer + nh_buf_used++;
|
||||
rv->next = NULL;
|
||||
last = &(rv->next);
|
||||
|
||||
rv->weight = nh->rtnh_hops;
|
||||
rv->iface = if_find_by_index(nh->rtnh_ifindex);
|
||||
if (!rv->iface)
|
||||
return NULL;
|
||||
|
||||
/* Nonexistent RTNH_PAYLOAD ?? */
|
||||
nl_attr_len = nh->rtnh_len - RTNH_LENGTH(0);
|
||||
nl_parse_attrs(RTNH_DATA(nh), a, sizeof(a));
|
||||
if (a[RTA_GATEWAY])
|
||||
{
|
||||
if (RTA_PAYLOAD(a[RTA_GATEWAY]) != sizeof(ip_addr))
|
||||
return NULL;
|
||||
|
||||
memcpy(&rv->gw, RTA_DATA(a[RTA_GATEWAY]), sizeof(ip_addr));
|
||||
ipa_ntoh(rv->gw);
|
||||
|
||||
neighbor *ng = neigh_find2(&p->p, &rv->gw, rv->iface,
|
||||
(nh->rtnh_flags & RTNH_F_ONLINK) ? NEF_ONLINK : 0);
|
||||
if (!ng || (ng->scope == SCOPE_HOST))
|
||||
return NULL;
|
||||
}
|
||||
else
|
||||
return NULL;
|
||||
|
||||
len -= NLMSG_ALIGN(nh->rtnh_len);
|
||||
nh = RTNH_NEXT(nh);
|
||||
}
|
||||
|
||||
return first;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Scanning of interfaces
|
||||
*/
|
||||
@ -490,6 +596,7 @@ krt_capable(rte *e)
|
||||
case RTD_BLACKHOLE:
|
||||
case RTD_UNREACHABLE:
|
||||
case RTD_PROHIBIT:
|
||||
case RTD_MULTIPATH:
|
||||
break;
|
||||
default:
|
||||
return 0;
|
||||
@ -497,6 +604,15 @@ krt_capable(rte *e)
|
||||
return 1;
|
||||
}
|
||||
|
||||
static inline int
|
||||
nh_bufsize(struct mpnh *nh)
|
||||
{
|
||||
int rv = 0;
|
||||
for (; nh != NULL; nh = nh->next)
|
||||
rv += RTNH_SIZE;
|
||||
return rv;
|
||||
}
|
||||
|
||||
static void
|
||||
nl_send_route(struct krt_proto *p, rte *e, int new)
|
||||
{
|
||||
@ -505,7 +621,7 @@ nl_send_route(struct krt_proto *p, rte *e, int new)
|
||||
struct {
|
||||
struct nlmsghdr h;
|
||||
struct rtmsg r;
|
||||
char buf[128];
|
||||
char buf[64 + nh_bufsize(a->nexthops)];
|
||||
} r;
|
||||
|
||||
DBG("nl_send_route(%I/%d,new=%d)\n", net->n.prefix, net->n.pxlen, new);
|
||||
@ -549,6 +665,10 @@ nl_send_route(struct krt_proto *p, rte *e, int new)
|
||||
case RTD_PROHIBIT:
|
||||
r.r.rtm_type = RTN_PROHIBIT;
|
||||
break;
|
||||
case RTD_MULTIPATH:
|
||||
r.r.rtm_type = RTN_UNICAST;
|
||||
nl_add_multipath(&r.h, sizeof(r), a->nexthops);
|
||||
break;
|
||||
default:
|
||||
bug("krt_capable inconsistent with nl_send_route");
|
||||
}
|
||||
@ -566,6 +686,7 @@ krt_set_notify(struct krt_proto *p, net *n UNUSED, rte *new, rte *old)
|
||||
nl_send_route(p, new, 1);
|
||||
}
|
||||
|
||||
|
||||
#define SKIP(ARG...) do { DBG("KRT: Ignoring route - " ARG); return; } while(0)
|
||||
|
||||
static void
|
||||
@ -671,6 +792,21 @@ nl_parse_route(struct nlmsghdr *h, int scan)
|
||||
switch (i->rtm_type)
|
||||
{
|
||||
case RTN_UNICAST:
|
||||
|
||||
if (a[RTA_MULTIPATH])
|
||||
{
|
||||
ra.dest = RTD_MULTIPATH;
|
||||
ra.nexthops = nl_parse_multipath(p, a[RTA_MULTIPATH]);
|
||||
if (!ra.nexthops)
|
||||
{
|
||||
log(L_ERR "KRT: Received strange multipath route %I/%d",
|
||||
net->n.prefix, net->n.pxlen);
|
||||
return;
|
||||
}
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
ra.iface = if_find_by_index(oif);
|
||||
if (!ra.iface)
|
||||
{
|
||||
|
||||
Loading…
Reference in New Issue
Block a user