zebra: add interface address apis for dplane

Add new apis for dplane interface address handling, based on
the existing api. The existing api is basically split in two:
the first part processes an incoming netlink message in the
dplane pthread, creating a dplane context with info about
the event. The second part runs in the main pthread and uses
the context data to update an interface or connected object.

Signed-off-by: Mark Stapp <mjs.ietf@gmail.com>
This commit is contained in:
Mark Stapp 2021-07-13 16:59:46 -04:00
parent 9d59df634c
commit e7c2c1985c
2 changed files with 328 additions and 1 deletions

View File

@ -1443,7 +1443,6 @@ int netlink_interface_addr(struct nlmsghdr *h, ns_id_t ns_id, int startup)
NULL, ifa->ifa_prefixlen);
}
/*
* Linux kernel does not send route delete on interface down/addr del
* so we have to re-process routes it owns (i.e. kernel routes)
@ -1454,6 +1453,323 @@ int netlink_interface_addr(struct nlmsghdr *h, ns_id_t ns_id, int startup)
return 0;
}
/*
* Parse and validate an incoming interface address change message,
* generating a dplane context object.
* This runs in the dplane pthread; the context is enqueued to the
* main pthread for processing.
*/
int netlink_interface_addr_dplane(struct nlmsghdr *h, ns_id_t ns_id,
int startup /*ignored*/)
{
int len;
struct ifaddrmsg *ifa;
struct rtattr *tb[IFA_MAX + 1];
void *addr;
void *broad;
char *label = NULL;
uint32_t metric = METRIC_MAX;
uint32_t kernel_flags = 0;
struct zebra_dplane_ctx *ctx;
struct prefix p;
ifa = NLMSG_DATA(h);
/* Validate message types */
if (h->nlmsg_type != RTM_NEWADDR && h->nlmsg_type != RTM_DELADDR)
return 0;
if (ifa->ifa_family != AF_INET && ifa->ifa_family != AF_INET6) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s: Invalid address family: %u",
__func__, nl_msg_type_to_str(h->nlmsg_type),
ifa->ifa_family);
return 0;
}
len = h->nlmsg_len - NLMSG_LENGTH(sizeof(struct ifaddrmsg));
if (len < 0) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s: netlink msg bad size: %d %zu",
__func__, nl_msg_type_to_str(h->nlmsg_type),
h->nlmsg_len,
(size_t)NLMSG_LENGTH(
sizeof(struct ifaddrmsg)));
return -1;
}
netlink_parse_rtattr(tb, IFA_MAX, IFA_RTA(ifa), len);
/* Flags passed through */
if (tb[IFA_FLAGS])
kernel_flags = *(int *)RTA_DATA(tb[IFA_FLAGS]);
else
kernel_flags = ifa->ifa_flags;
if (IS_ZEBRA_DEBUG_KERNEL) { /* remove this line to see initial ifcfg */
char buf[PREFIX_STRLEN];
zlog_debug("%s: %s nsid %u ifindex %u flags 0x%x:", __func__,
nl_msg_type_to_str(h->nlmsg_type), ns_id,
ifa->ifa_index, kernel_flags);
if (tb[IFA_LOCAL])
zlog_debug(" IFA_LOCAL %s/%d",
inet_ntop(ifa->ifa_family,
RTA_DATA(tb[IFA_LOCAL]), buf,
sizeof(buf)),
ifa->ifa_prefixlen);
if (tb[IFA_ADDRESS])
zlog_debug(" IFA_ADDRESS %s/%d",
inet_ntop(ifa->ifa_family,
RTA_DATA(tb[IFA_ADDRESS]), buf,
sizeof(buf)),
ifa->ifa_prefixlen);
if (tb[IFA_BROADCAST])
zlog_debug(" IFA_BROADCAST %s/%d",
inet_ntop(ifa->ifa_family,
RTA_DATA(tb[IFA_BROADCAST]), buf,
sizeof(buf)),
ifa->ifa_prefixlen);
if (tb[IFA_LABEL])
zlog_debug(" IFA_LABEL %s",
(const char *)RTA_DATA(tb[IFA_LABEL]));
if (tb[IFA_CACHEINFO]) {
struct ifa_cacheinfo *ci = RTA_DATA(tb[IFA_CACHEINFO]);
zlog_debug(" IFA_CACHEINFO pref %d, valid %d",
ci->ifa_prefered, ci->ifa_valid);
}
}
/* Validate prefix length */
if (ifa->ifa_family == AF_INET
&& ifa->ifa_prefixlen > IPV4_MAX_BITLEN) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s: Invalid prefix length: %u",
__func__, nl_msg_type_to_str(h->nlmsg_type),
ifa->ifa_prefixlen);
return -1;
}
if (ifa->ifa_family == AF_INET6) {
if (ifa->ifa_prefixlen > IPV6_MAX_BITLEN) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s: Invalid prefix length: %u",
__func__,
nl_msg_type_to_str(h->nlmsg_type),
ifa->ifa_prefixlen);
return -1;
}
/* Only consider valid addresses; we'll not get a kernel
* notification till IPv6 DAD has completed, but at init
* time, FRR does query for and will receive all addresses.
*/
if (h->nlmsg_type == RTM_NEWADDR
&& (kernel_flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s: Invalid/tentative addr",
__func__,
nl_msg_type_to_str(h->nlmsg_type));
return 0;
}
}
/* logic copied from iproute2/ip/ipaddress.c:print_addrinfo() */
if (tb[IFA_LOCAL] == NULL)
tb[IFA_LOCAL] = tb[IFA_ADDRESS];
if (tb[IFA_ADDRESS] == NULL)
tb[IFA_ADDRESS] = tb[IFA_LOCAL];
/* local interface address */
addr = (tb[IFA_LOCAL] ? RTA_DATA(tb[IFA_LOCAL]) : NULL);
/* addr is primary key, SOL if we don't have one */
if (addr == NULL) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s: No local interface address",
__func__, nl_msg_type_to_str(h->nlmsg_type));
return -1;
}
/* Allocate a context object, now that validation is done. */
ctx = dplane_ctx_alloc();
if (h->nlmsg_type == RTM_NEWADDR)
dplane_ctx_set_op(ctx, DPLANE_OP_INTF_ADDR_ADD);
else
dplane_ctx_set_op(ctx, DPLANE_OP_INTF_ADDR_DEL);
dplane_ctx_set_ifindex(ctx, ifa->ifa_index);
dplane_ctx_set_ns_id(ctx, ns_id);
/* Convert addr to prefix */
memset(&p, 0, sizeof(p));
p.family = ifa->ifa_family;
p.prefixlen = ifa->ifa_prefixlen;
if (p.family == AF_INET)
p.u.prefix4 = *(struct in_addr *)addr;
else
p.u.prefix6 = *(struct in6_addr *)addr;
dplane_ctx_set_intf_addr(ctx, &p);
/* is there a peer address? */
if (tb[IFA_ADDRESS]
&& memcmp(RTA_DATA(tb[IFA_ADDRESS]), RTA_DATA(tb[IFA_LOCAL]),
RTA_PAYLOAD(tb[IFA_ADDRESS]))) {
broad = RTA_DATA(tb[IFA_ADDRESS]);
dplane_ctx_intf_set_connected(ctx);
} else if (tb[IFA_BROADCAST]) {
/* seeking a broadcast address */
broad = RTA_DATA(tb[IFA_BROADCAST]);
dplane_ctx_intf_set_broadcast(ctx);
} else
broad = NULL;
if (broad) {
/* Convert addr to prefix */
memset(&p, 0, sizeof(p));
p.family = ifa->ifa_family;
p.prefixlen = ifa->ifa_prefixlen;
if (p.family == AF_INET)
p.u.prefix4 = *(struct in_addr *)broad;
else
p.u.prefix6 = *(struct in6_addr *)broad;
dplane_ctx_set_intf_dest(ctx, &p);
}
/* Flags. */
if (kernel_flags & IFA_F_SECONDARY)
dplane_ctx_intf_set_secondary(ctx);
/* Label */
if (tb[IFA_LABEL]) {
label = (char *)RTA_DATA(tb[IFA_LABEL]);
dplane_ctx_set_intf_label(ctx, label);
}
if (tb[IFA_RT_PRIORITY])
metric = *(uint32_t *)RTA_DATA(tb[IFA_RT_PRIORITY]);
dplane_ctx_set_intf_metric(ctx, metric);
/* Enqueue ctx for main pthread to process */
dplane_provider_enqueue_to_zebra(ctx);
return 0;
}
/*
* Handle an interface addr event based on info in a dplane context object.
* This runs in the main pthread, using the info in the context object to
* modify an interface.
*/
int netlink_interface_addr_ctx(struct zebra_dplane_ctx *ctx)
{
int ret = -1;
struct interface *ifp;
uint8_t flags = 0;
const char *label = NULL;
ns_id_t ns_id;
struct zebra_ns *zns;
uint32_t metric = METRIC_MAX;
ifindex_t ifindex;
const struct prefix *addr, *dest = NULL;
enum dplane_op_e op;
op = dplane_ctx_get_op(ctx);
ns_id = dplane_ctx_get_ns_id(ctx);
zns = zebra_ns_lookup(ns_id);
if (zns == NULL) {
/* No ns - deleted maybe? */
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: can't find zns id %u", __func__, ns_id);
goto done;
}
ifindex = dplane_ctx_get_ifindex(ctx);
ifp = if_lookup_by_index_per_ns(zns, ifindex);
if (ifp == NULL) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: can't find ifp at nsid %u index %d",
__func__, ns_id, ifindex);
goto done;
}
addr = dplane_ctx_get_intf_addr(ctx);
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s: ifindex %u, addr %pFX", __func__,
dplane_op2str(op), ifindex, addr);
/* Is there a peer or broadcast address? */
dest = dplane_ctx_get_intf_dest(ctx);
if (dest->prefixlen == 0)
dest = NULL;
if (dplane_ctx_intf_is_connected(ctx))
SET_FLAG(flags, ZEBRA_IFA_PEER);
/* Flags. */
if (dplane_ctx_intf_is_secondary(ctx))
SET_FLAG(flags, ZEBRA_IFA_SECONDARY);
/* Label? */
if (dplane_ctx_intf_has_label(ctx))
label = dplane_ctx_get_intf_label(ctx);
if (label && strcmp(ifp->name, label) == 0)
label = NULL;
metric = dplane_ctx_get_intf_metric(ctx);
/* Register interface address to the interface. */
if (addr->family == AF_INET) {
if (op == DPLANE_OP_INTF_ADDR_ADD)
connected_add_ipv4(
ifp, flags, &addr->u.prefix4, addr->prefixlen,
dest ? &dest->u.prefix4 : NULL, label, metric);
else if (CHECK_FLAG(flags, ZEBRA_IFA_PEER)) {
/* Delete with a peer address */
connected_delete_ipv4(ifp, flags, &addr->u.prefix4,
addr->prefixlen,
&dest->u.prefix4);
} else
connected_delete_ipv4(ifp, flags, &addr->u.prefix4,
addr->prefixlen, NULL);
}
if (addr->family == AF_INET6) {
if (op == DPLANE_OP_INTF_ADDR_ADD) {
connected_add_ipv6(ifp, flags, &addr->u.prefix6,
dest ? &dest->u.prefix6 : NULL,
addr->prefixlen, label, metric);
} else
connected_delete_ipv6(ifp, &addr->u.prefix6, NULL,
addr->prefixlen);
}
/*
* Linux kernel does not send route delete on interface down/addr del
* so we have to re-process routes it owns (i.e. kernel routes)
*/
if (op != DPLANE_OP_INTF_ADDR_ADD)
rib_update(RIB_UPDATE_KERNEL);
ret = 0;
done:
/* We're responsible for the ctx object */
dplane_ctx_fini(&ctx);
return ret;
}
int netlink_link_change(struct nlmsghdr *h, ns_id_t ns_id, int startup)
{
int len;

View File

@ -29,6 +29,17 @@ extern "C" {
extern int netlink_interface_addr(struct nlmsghdr *h, ns_id_t ns_id,
int startup);
/*
* Parse an incoming interface address change message, generate a dplane
* context object for processing.
*/
int netlink_interface_addr_dplane(struct nlmsghdr *h, ns_id_t ns_id,
int startup);
/* Handle an interface addr change event. */
int netlink_interface_addr_ctx(struct zebra_dplane_ctx *ctx);
extern int netlink_link_change(struct nlmsghdr *h, ns_id_t ns_id, int startup);
extern int interface_lookup_netlink(struct zebra_ns *zns);