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Improve the performance of DHCP relay.

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On machines with many interfaces, enumerating them
via netlink on each packet reciept is slow,
and unneccesary. All we need is the local address->interface
mapping, which can be cached in the relay structures.
This commit is contained in:
Simon Kelley
2022-02-01 00:18:44 +00:00
parent dbceeb4178
commit 7fbf1cce7b
5 changed files with 217 additions and 207 deletions
Download Patch File Download Diff File Expand all files Collapse all files

169
src/rfc3315.c
View File

@@ -2100,110 +2100,113 @@ static unsigned int opt6_uint(unsigned char *opt, int offset, int size)
return ret;
}
void relay_upstream6(struct dhcp_relay *relay, ssize_t sz,
struct in6_addr *peer_address, u32 scope_id, time_t now)
int relay_upstream6(int iface_index, ssize_t sz,
struct in6_addr *peer_address, u32 scope_id, time_t now)
{
/* ->local is same value for all relays on ->current chain */
union all_addr from;
unsigned char *header;
unsigned char *inbuff = daemon->dhcp_packet.iov_base;
int msg_type = *inbuff;
int hopcount;
int hopcount, o;
struct in6_addr multicast;
unsigned int maclen, mactype;
unsigned char mac[DHCP_CHADDR_MAX];
struct dhcp_relay *relay;
for (relay = daemon->relay6; relay; relay = relay->next)
if (relay->iface_index != 0 && relay->iface_index == iface_index)
break;
/* No relay config. */
if (!relay)
return 0;
inet_pton(AF_INET6, ALL_SERVERS, &multicast);
get_client_mac(peer_address, scope_id, mac, &maclen, &mactype, now);
/* source address == relay address */
from.addr6 = relay->local.addr6;
/* Get hop count from nested relayed message */
if (msg_type == DHCP6RELAYFORW)
hopcount = *((unsigned char *)inbuff+1) + 1;
else
hopcount = 0;
/* RFC 3315 HOP_COUNT_LIMIT */
if (hopcount > 32)
return;
reset_counter();
if ((header = put_opt6(NULL, 34)))
/* RFC 3315 HOP_COUNT_LIMIT */
if (hopcount > 32 || !(header = put_opt6(NULL, 34)))
return 1;
header[0] = DHCP6RELAYFORW;
header[1] = hopcount;
memcpy(&header[18], peer_address, IN6ADDRSZ);
/* RFC-6939 */
if (maclen != 0)
{
int o;
header[0] = DHCP6RELAYFORW;
header[1] = hopcount;
memcpy(&header[2], &relay->local.addr6, IN6ADDRSZ);
memcpy(&header[18], peer_address, IN6ADDRSZ);
/* RFC-6939 */
if (maclen != 0)
{
o = new_opt6(OPTION6_CLIENT_MAC);
put_opt6_short(mactype);
put_opt6(mac, maclen);
end_opt6(o);
}
o = new_opt6(OPTION6_RELAY_MSG);
put_opt6(inbuff, sz);
o = new_opt6(OPTION6_CLIENT_MAC);
put_opt6_short(mactype);
put_opt6(mac, maclen);
end_opt6(o);
for (; relay; relay = relay->current)
{
union mysockaddr to;
to.sa.sa_family = AF_INET6;
to.in6.sin6_addr = relay->server.addr6;
to.in6.sin6_port = htons(DHCPV6_SERVER_PORT);
to.in6.sin6_flowinfo = 0;
to.in6.sin6_scope_id = 0;
if (IN6_ARE_ADDR_EQUAL(&relay->server.addr6, &multicast))
{
int multicast_iface;
if (!relay->interface || strchr(relay->interface, '*') ||
(multicast_iface = if_nametoindex(relay->interface)) == 0 ||
setsockopt(daemon->dhcp6fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &multicast_iface, sizeof(multicast_iface)) == -1)
{
my_syslog(MS_DHCP | LOG_ERR, _("Cannot multicast DHCP relay via interface %s"), relay->interface);
return;
}
}
#ifdef HAVE_DUMPFILE
{
union mysockaddr fromsock;
fromsock.in6.sin6_port = htons(DHCPV6_SERVER_PORT);
fromsock.in6.sin6_addr = from.addr6;
fromsock.sa.sa_family = AF_INET6;
fromsock.in6.sin6_flowinfo = 0;
fromsock.in6.sin6_scope_id = 0;
dump_packet(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1), &fromsock, &to, 0);
}
#endif
send_from(daemon->dhcp6fd, 0, daemon->outpacket.iov_base, save_counter(-1), &to, &from, 0);
if (option_bool(OPT_LOG_OPTS))
{
inet_ntop(AF_INET6, &relay->local, daemon->addrbuff, ADDRSTRLEN);
if (IN6_ARE_ADDR_EQUAL(&relay->server.addr6, &multicast))
snprintf(daemon->namebuff, MAXDNAME, _("multicast via %s"), relay->interface);
else
inet_ntop(AF_INET6, &relay->server, daemon->namebuff, ADDRSTRLEN);
my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay at %s -> %s"), daemon->addrbuff, daemon->namebuff);
}
/* Save this for replies */
relay->iface_index = scope_id;
}
}
o = new_opt6(OPTION6_RELAY_MSG);
put_opt6(inbuff, sz);
end_opt6(o);
for (; relay; relay = relay->next)
if (relay->iface_index != 0 && relay->iface_index == iface_index)
{
union mysockaddr to;
union all_addr from;
/* source address == relay address */
from.addr6 = relay->local.addr6;
memcpy(&header[2], &relay->local.addr6, IN6ADDRSZ);
to.sa.sa_family = AF_INET6;
to.in6.sin6_addr = relay->server.addr6;
to.in6.sin6_port = htons(DHCPV6_SERVER_PORT);
to.in6.sin6_flowinfo = 0;
to.in6.sin6_scope_id = 0;
if (IN6_ARE_ADDR_EQUAL(&relay->server.addr6, &multicast))
{
int multicast_iface;
if (!relay->interface || strchr(relay->interface, '*') ||
(multicast_iface = if_nametoindex(relay->interface)) == 0 ||
setsockopt(daemon->dhcp6fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &multicast_iface, sizeof(multicast_iface)) == -1)
{
my_syslog(MS_DHCP | LOG_ERR, _("Cannot multicast DHCP relay via interface %s"), relay->interface);
continue;
}
}
#ifdef HAVE_DUMPFILE
{
union mysockaddr fromsock;
fromsock.in6.sin6_port = htons(DHCPV6_SERVER_PORT);
fromsock.in6.sin6_addr = from.addr6;
fromsock.sa.sa_family = AF_INET6;
fromsock.in6.sin6_flowinfo = 0;
fromsock.in6.sin6_scope_id = 0;
dump_packet(DUMP_DHCPV6, (void *)daemon->outpacket.iov_base, save_counter(-1), &fromsock, &to, 0);
}
#endif
send_from(daemon->dhcp6fd, 0, daemon->outpacket.iov_base, save_counter(-1), &to, &from, 0);
if (option_bool(OPT_LOG_OPTS))
{
inet_ntop(AF_INET6, &relay->local, daemon->addrbuff, ADDRSTRLEN);
if (IN6_ARE_ADDR_EQUAL(&relay->server.addr6, &multicast))
snprintf(daemon->namebuff, MAXDNAME, _("multicast via %s"), relay->interface);
else
inet_ntop(AF_INET6, &relay->server, daemon->namebuff, ADDRSTRLEN);
my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay at %s -> %s"), daemon->addrbuff, daemon->namebuff);
}
}
return 1;
}
int relay_reply6(struct sockaddr_in6 *peer, ssize_t sz, char *arrival_interface)