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-rw-r--r--extras/strongswan/vpp_sswan/kernel_vpp_net.c752
1 files changed, 752 insertions, 0 deletions
diff --git a/extras/strongswan/vpp_sswan/kernel_vpp_net.c b/extras/strongswan/vpp_sswan/kernel_vpp_net.c
new file mode 100644
index 00000000000..02f002a3183
--- /dev/null
+++ b/extras/strongswan/vpp_sswan/kernel_vpp_net.c
@@ -0,0 +1,752 @@
+/*
+ * Copyright (c) 2022 Intel and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <utils/debug.h>
+#include <vlibapi/api.h>
+#include <vlibmemory/api.h>
+#include <threading/thread.h>
+#include <threading/mutex.h>
+
+#define vl_typedefs
+#define vl_endianfun
+/* Include the (first) vlib-api API definition layer */
+#include <vlibmemory/vl_memory_api_h.h>
+/* Include the current layer (third) vpp API definition layer */
+#include <vpp/api/vpe_types.api.h>
+#include <vpp/api/vpe.api.h>
+
+#include <vnet/ip-neighbor/ip_neighbor.api_enum.h>
+#include <vnet/ip-neighbor/ip_neighbor.api_types.h>
+#include <vnet/ip/ip.api_enum.h>
+#include <vnet/ip/ip.api_types.h>
+#include <vnet/interface.api_enum.h>
+#include <vnet/interface.api_types.h>
+#undef vl_typedefs
+#undef vl_endianfun
+
+#include "kernel_vpp_net.h"
+#include "kernel_vpp_shared.h"
+
+typedef struct private_kernel_vpp_net_t private_kernel_vpp_net_t;
+
+/**
+ * Private data of kernel_vpp_net implementation.
+ */
+struct private_kernel_vpp_net_t
+{
+
+ /**
+ * Public interface.
+ */
+ kernel_vpp_net_t public;
+
+ /**
+ * Mutex to access interface list
+ */
+ mutex_t *mutex;
+
+ /**
+ * Known interfaces, as iface_t
+ */
+ linked_list_t *ifaces;
+
+ /**
+ * Inteface update thread
+ */
+ thread_t *net_update;
+
+ /**
+ * TRUE if interface events enabled
+ */
+ bool events_on;
+};
+
+/**
+ * Interface entry
+ */
+typedef struct
+{
+ /** interface index */
+ uint32_t index;
+ /** interface name */
+ char if_name[64];
+ /** list of known addresses, as host_t */
+ linked_list_t *addrs;
+ /** TRUE if up */
+ bool up;
+} iface_t;
+
+/**
+ * Address enumerator
+ */
+typedef struct
+{
+ /** implements enumerator_t */
+ enumerator_t public;
+ /** what kind of address should we enumerate? */
+ kernel_address_type_t which;
+ /** enumerator over interfaces */
+ enumerator_t *ifaces;
+ /** current enumerator over addresses, or NULL */
+ enumerator_t *addrs;
+ /** mutex to unlock on destruction */
+ mutex_t *mutex;
+} addr_enumerator_t;
+
+/**
+ * FIB path entry
+ */
+typedef struct
+{
+ chunk_t next_hop;
+ uint32_t sw_if_index;
+ uint8_t preference;
+} fib_path_t;
+
+/**
+ * Get an iface entry for a local address
+ */
+static iface_t *
+address2entry (private_kernel_vpp_net_t *this, host_t *ip)
+{
+ enumerator_t *ifaces, *addrs;
+ iface_t *entry, *found = NULL;
+ host_t *host;
+
+ ifaces = this->ifaces->create_enumerator (this->ifaces);
+ while (!found && ifaces->enumerate (ifaces, &entry))
+ {
+ addrs = entry->addrs->create_enumerator (entry->addrs);
+ while (!found && addrs->enumerate (addrs, &host))
+ {
+ if (host->ip_equals (host, ip))
+ {
+ found = entry;
+ }
+ }
+ addrs->destroy (addrs);
+ }
+ ifaces->destroy (ifaces);
+
+ return found;
+}
+
+/**
+ * Add or remove a route
+ */
+static status_t
+manage_route (private_kernel_vpp_net_t *this, bool add, chunk_t dst,
+ uint8_t prefixlen, host_t *gtw, char *name)
+{
+ char *out;
+ int out_len;
+ enumerator_t *enumerator;
+ iface_t *entry;
+ vl_api_ip_route_add_del_t *mp;
+ vl_api_ip_route_add_del_reply_t *rmp;
+ vl_api_fib_path_t *apath;
+ bool exists = FALSE;
+
+ this->mutex->lock (this->mutex);
+ enumerator = this->ifaces->create_enumerator (this->ifaces);
+ while (enumerator->enumerate (enumerator, &entry))
+ {
+ if (streq (name, entry->if_name))
+ {
+ exists = TRUE;
+ break;
+ }
+ }
+ enumerator->destroy (enumerator);
+ this->mutex->unlock (this->mutex);
+
+ if (!exists)
+ {
+ DBG1 (DBG_NET, "if_name %s not found", name);
+ return NOT_FOUND;
+ }
+
+ mp = vl_msg_api_alloc (sizeof (*mp) + sizeof (*apath));
+ memset (mp, 0, sizeof (*mp) + sizeof (*apath));
+ u16 msg_id = vl_msg_api_get_msg_index ((u8 *) "ip_route_add_del_b8ecfe0d");
+ mp->_vl_msg_id = ntohs (msg_id);
+ mp->is_add = add;
+ mp->route.prefix.len = prefixlen;
+ mp->route.n_paths = 1;
+ apath = &mp->route.paths[0];
+ apath->sw_if_index = ntohl (entry->index);
+ apath->rpf_id = ~0;
+ apath->weight = 1;
+ switch (dst.len)
+ {
+ case 4:
+ mp->route.prefix.address.af = ntohl (ADDRESS_IP4);
+ memcpy (&mp->route.prefix.address.un.ip4, dst.ptr, dst.len);
+ if (gtw)
+ {
+ chunk_t addr = gtw->get_address (gtw);
+ apath->proto = ntohl (FIB_API_PATH_NH_PROTO_IP4);
+ memcpy (&apath->nh.address.ip4, addr.ptr, dst.len);
+ }
+ break;
+ case 16:
+ mp->route.prefix.address.af = ntohl (ADDRESS_IP6);
+ memcpy (&mp->route.prefix.address.un.ip6, dst.ptr, dst.len);
+ if (gtw)
+ {
+ chunk_t addr = gtw->get_address (gtw);
+ apath->proto = ntohl (FIB_API_PATH_NH_PROTO_IP6);
+ memcpy (&apath->nh.address.ip6, addr.ptr, dst.len);
+ }
+ break;
+ default:
+ vl_msg_api_free (mp);
+ return FAILED;
+ }
+
+ if (vac->send (vac, (char *) mp, sizeof (*mp) + sizeof (*apath), &out,
+ &out_len))
+ {
+ DBG1 (DBG_KNL, "vac %sing route failed", add ? "add" : "remov");
+ vl_msg_api_free (mp);
+ return FAILED;
+ }
+ rmp = (void *) out;
+ vl_msg_api_free (mp);
+ if (rmp->retval)
+ {
+ DBG1 (DBG_KNL, "%s route failed %d", add ? "add" : "delete",
+ ntohl (rmp->retval));
+ free (out);
+ return FAILED;
+ }
+ free (out);
+ return SUCCESS;
+}
+
+/**
+ * Check if an address or net (addr with prefix net bits) is in
+ * subnet (net with net_len net bits)
+ */
+static bool
+addr_in_subnet (chunk_t addr, int prefix, chunk_t net, int net_len)
+{
+ static const u_char mask[] = {
+ 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe
+ };
+ int byte = 0;
+
+ if (net_len == 0)
+ { /* any address matches a /0 network */
+ return TRUE;
+ }
+ if (addr.len != net.len || net_len > 8 * net.len || prefix < net_len)
+ {
+ return FALSE;
+ }
+ /* scan through all bytes in network order */
+ while (net_len > 0)
+ {
+ if (net_len < 8)
+ {
+ return (mask[net_len] & addr.ptr[byte]) ==
+ (mask[net_len] & net.ptr[byte]);
+ }
+ else
+ {
+ if (addr.ptr[byte] != net.ptr[byte])
+ {
+ return FALSE;
+ }
+ byte++;
+ net_len -= 8;
+ }
+ }
+ return TRUE;
+}
+
+/**
+ * Get a route: If "nexthop" the nexthop is returned, source addr otherwise
+ */
+static host_t *
+get_route (private_kernel_vpp_net_t *this, host_t *dest, int prefix,
+ bool nexthop, char **iface, host_t *src)
+{
+ fib_path_t path;
+ char *out, *tmp;
+ int out_len, i, num;
+ vl_api_fib_path_t *fp;
+ host_t *addr = NULL;
+ enumerator_t *enumerator;
+ iface_t *entry;
+ int family;
+
+ path.sw_if_index = ~0;
+ path.preference = ~0;
+ path.next_hop = chunk_empty;
+
+ vl_api_ip_route_dump_t *mp;
+ vl_api_ip_route_details_t *rmp;
+
+ mp = vl_msg_api_alloc (sizeof (*mp));
+ clib_memset (mp, 0, sizeof (*mp));
+ u16 msg_id = vl_msg_api_get_msg_index ((u8 *) "ip_route_dump_b9d2e09e");
+ mp->_vl_msg_id = htons (msg_id);
+ mp->table.is_ip6 = dest->get_family (dest) == AF_INET6 ? 1 : 0;
+ if (vac->send_dump (vac, (char *) mp, sizeof (*mp), &out, &out_len))
+ {
+ vl_msg_api_free (mp);
+ DBG2 (DBG_KNL, "send VL_API_IP_ROUTE_ADD_DEL failed");
+ return NULL;
+ }
+ vl_msg_api_free (mp);
+
+ if (dest->get_family (dest) == AF_INET)
+ {
+ i = 0;
+ family = AF_INET;
+ if (prefix == -1)
+ prefix = 32;
+
+ tmp = out;
+ while (tmp < (out + out_len))
+ {
+ rmp = (void *) tmp;
+ num = rmp->route.n_paths;
+
+ if (rmp->route.prefix.len &&
+ addr_in_subnet (
+ dest->get_address (dest), prefix,
+ chunk_create (rmp->route.prefix.address.un.ip4, 4),
+ rmp->route.prefix.len))
+ {
+ fp = rmp->route.paths;
+ for (i = 0; i < num; i++)
+ {
+#define IS_IP4_ANY(a) (a[0] == 0 && a[1] == 0 && a[2] == 0 & a[3] == 0)
+ if (fp->type == FIB_API_PATH_TYPE_DROP)
+ {
+ fp++;
+ continue;
+ }
+ if ((fp->preference < path.preference) ||
+ (path.sw_if_index == ~0) ||
+ IS_IP4_ANY (path.next_hop.ptr))
+ {
+ path.sw_if_index = ntohl (fp->sw_if_index);
+ path.preference = fp->preference;
+ if (path.next_hop.ptr)
+ vl_msg_api_free (path.next_hop.ptr);
+ path.next_hop = chunk_create (fp->nh.address.ip4, 4);
+ }
+ fp++;
+ }
+ }
+ tmp += sizeof (*rmp) + (sizeof (*fp) * num);
+ }
+ }
+ else
+ {
+ DBG1 (DBG_KNL, "not yet support ip6");
+ return NULL;
+ }
+
+ if (path.next_hop.len)
+ {
+ if (nexthop)
+ {
+ if (iface)
+ {
+ *iface = NULL;
+ this->mutex->lock (this->mutex);
+ enumerator = this->ifaces->create_enumerator (this->ifaces);
+ while (enumerator->enumerate (enumerator, &entry))
+ {
+ if (entry->index == path.sw_if_index)
+ {
+ *iface = strdup (entry->if_name);
+ break;
+ }
+ }
+ enumerator->destroy (enumerator);
+ this->mutex->unlock (this->mutex);
+ }
+ addr = host_create_from_chunk (family, path.next_hop, 0);
+ }
+ else
+ {
+ if (src)
+ {
+ addr = src->clone (src);
+ }
+ }
+ }
+
+ free (out);
+
+ return addr;
+}
+
+METHOD (enumerator_t, addr_enumerate, bool, addr_enumerator_t *this,
+ va_list args)
+{
+ iface_t *entry;
+ host_t **host;
+
+ VA_ARGS_VGET (args, host);
+
+ while (TRUE)
+ {
+ while (!this->addrs)
+ {
+ if (!this->ifaces->enumerate (this->ifaces, &entry))
+ {
+ return FALSE;
+ }
+ if (!entry->up && !(this->which & ADDR_TYPE_DOWN))
+ {
+ continue;
+ }
+ this->addrs = entry->addrs->create_enumerator (entry->addrs);
+ }
+ if (this->addrs->enumerate (this->addrs, host))
+ {
+ return TRUE;
+ }
+ this->addrs->destroy (this->addrs);
+ this->addrs = NULL;
+ }
+}
+
+METHOD (enumerator_t, addr_destroy, void, addr_enumerator_t *this)
+{
+ DESTROY_IF (this->addrs);
+ this->ifaces->destroy (this->ifaces);
+ this->mutex->unlock (this->mutex);
+ free (this);
+}
+
+METHOD (kernel_net_t, get_interface_name, bool, private_kernel_vpp_net_t *this,
+ host_t *ip, char **name)
+{
+ iface_t *entry;
+
+ this->mutex->lock (this->mutex);
+ entry = address2entry (this, ip);
+ if (entry && name)
+ {
+ *name = strdup (entry->if_name);
+ }
+ this->mutex->unlock (this->mutex);
+
+ return entry != NULL;
+}
+
+METHOD (kernel_net_t, create_address_enumerator, enumerator_t *,
+ private_kernel_vpp_net_t *this, kernel_address_type_t which)
+{
+ addr_enumerator_t *enumerator;
+
+ if (!(which & ADDR_TYPE_REGULAR))
+ {
+ /* we currently have no virtual, but regular IPs only */
+ return enumerator_create_empty ();
+ }
+
+ this->mutex->lock (this->mutex);
+
+ INIT(enumerator,
+ .public = {
+ .enumerate = enumerator_enumerate_default,
+ .venumerate = _addr_enumerate,
+ .destroy = _addr_destroy,
+ },
+ .which = which,
+ .ifaces = this->ifaces->create_enumerator(this->ifaces),
+ .mutex = this->mutex,
+ );
+ return &enumerator->public;
+}
+
+METHOD (kernel_net_t, get_source_addr, host_t *,
+ private_kernel_vpp_net_t *this, host_t *dest, host_t *src)
+{
+ return get_route (this, dest, -1, FALSE, NULL, src);
+}
+
+METHOD (kernel_net_t, get_nexthop, host_t *, private_kernel_vpp_net_t *this,
+ host_t *dest, int prefix, host_t *src, char **iface)
+{
+ return get_route (this, dest, prefix, TRUE, iface, src);
+}
+
+METHOD (kernel_net_t, add_ip, status_t, private_kernel_vpp_net_t *this,
+ host_t *virtual_ip, int prefix, char *iface_name)
+{
+ return NOT_SUPPORTED;
+}
+
+METHOD (kernel_net_t, del_ip, status_t, private_kernel_vpp_net_t *this,
+ host_t *virtual_ip, int prefix, bool wait)
+{
+ return NOT_SUPPORTED;
+}
+
+METHOD (kernel_net_t, add_route, status_t, private_kernel_vpp_net_t *this,
+ chunk_t dst_net, u_int8_t prefixlen, host_t *gateway, host_t *src_ip,
+ char *if_name)
+{
+ return manage_route (this, TRUE, dst_net, prefixlen, gateway, if_name);
+}
+
+METHOD (kernel_net_t, del_route, status_t, private_kernel_vpp_net_t *this,
+ chunk_t dst_net, u_int8_t prefixlen, host_t *gateway, host_t *src_ip,
+ char *if_name)
+{
+ return manage_route (this, FALSE, dst_net, prefixlen, gateway, if_name);
+}
+
+static void
+iface_destroy (iface_t *this)
+{
+ this->addrs->destroy_offset (this->addrs, offsetof (host_t, destroy));
+ free (this);
+}
+
+METHOD (kernel_net_t, destroy, void, private_kernel_vpp_net_t *this)
+{
+ this->net_update->cancel (this->net_update);
+ this->mutex->destroy (this->mutex);
+ this->ifaces->destroy_function (this->ifaces, (void *) iface_destroy);
+ free (this);
+}
+
+/**
+ * Update addresses for an iface entry
+ */
+static void
+update_addrs (private_kernel_vpp_net_t *this, iface_t *entry)
+{
+ char *out;
+ int out_len, i, num;
+ vl_api_ip_address_dump_t *mp;
+ vl_api_ip_address_details_t *rmp, *tmp;
+ linked_list_t *addrs;
+ host_t *host;
+
+ mp = vl_msg_api_alloc (sizeof (*mp));
+ clib_memset (mp, 0, sizeof (*mp));
+ u16 msg_id = vl_msg_api_get_msg_index ((u8 *) "ip_address_dump_2d033de4");
+ mp->_vl_msg_id = htons (msg_id);
+ mp->sw_if_index = htonl (entry->index);
+ mp->is_ipv6 = 0;
+ if (vac->send_dump (vac, (char *) mp, sizeof (*mp), &out, &out_len))
+ {
+ DBG2 (DBG_NET, "update_addrs : send VL_API_IP_ADDRESS_DUMP ipv4 failed");
+ vl_msg_api_free (mp);
+ return;
+ }
+ num = out_len / sizeof (*rmp);
+ addrs = linked_list_create ();
+ tmp = (vl_api_ip_address_details_t *) out;
+ for (i = 0; i < num; i++)
+ {
+ tmp += i;
+ rmp = tmp;
+ host = host_create_from_chunk (
+ AF_INET, chunk_create (rmp->prefix.address.un.ip4, 4), 0);
+ addrs->insert_last (addrs, host);
+ }
+ free (out);
+
+ mp->is_ipv6 = 1;
+ if (vac->send_dump (vac, (char *) mp, sizeof (*mp), &out, &out_len))
+ {
+ DBG2 (DBG_NET, "update_addrs : send VL_API_IP_ADDRESS_DUMP ipv6 failed");
+ vl_msg_api_free (mp);
+ return;
+ }
+ num = out_len / sizeof (*rmp);
+ tmp = (vl_api_ip_address_details_t *) out;
+ for (i = 0; i < num; i++)
+ {
+ tmp += i;
+ rmp = tmp;
+ host = host_create_from_chunk (
+ AF_INET6, chunk_create (rmp->prefix.address.un.ip6, 16), 0);
+ addrs->insert_last (addrs, host);
+ }
+ vl_msg_api_free (mp);
+ free (out);
+
+ entry->addrs->destroy (entry->addrs);
+ entry->addrs =
+ linked_list_create_from_enumerator (addrs->create_enumerator (addrs));
+ addrs->destroy (addrs);
+}
+
+/**
+ * VPP API interface event callback
+ */
+static void
+event_cb (char *data, int data_len, void *ctx)
+{
+ private_kernel_vpp_net_t *this = ctx;
+ vl_api_sw_interface_event_t *event;
+ iface_t *entry;
+ enumerator_t *enumerator;
+
+ event = (void *) data;
+ this->mutex->lock (this->mutex);
+ enumerator = this->ifaces->create_enumerator (this->ifaces);
+ while (enumerator->enumerate (enumerator, &entry))
+ {
+ if (entry->index == ntohl (event->sw_if_index))
+ {
+ if (event->deleted)
+ {
+ this->ifaces->remove_at (this->ifaces, enumerator);
+ DBG2 (DBG_NET, "interface deleted %u %s", entry->index,
+ entry->if_name);
+ iface_destroy (entry);
+ }
+ else if (entry->up != (event->flags & IF_STATUS_API_FLAG_LINK_UP))
+ {
+ entry->up =
+ (event->flags & IF_STATUS_API_FLAG_LINK_UP) ? TRUE : FALSE;
+ DBG2 (DBG_NET, "interface state changed %u %s %s", entry->index,
+ entry->if_name, entry->up ? "UP" : "DOWN");
+ }
+ break;
+ }
+ }
+ enumerator->destroy (enumerator);
+ this->mutex->unlock (this->mutex);
+ free (data);
+}
+
+/**
+ * Inteface update thread (update interface list and interface address)
+ */
+static void *
+net_update_thread_fn (private_kernel_vpp_net_t *this)
+{
+ status_t rv;
+ while (1)
+ {
+ char *out;
+ int out_len;
+ vl_api_sw_interface_dump_t *mp;
+ vl_api_sw_interface_details_t *rmp;
+ enumerator_t *enumerator;
+ iface_t *entry;
+
+ mp = vl_msg_api_alloc (sizeof (*mp));
+ memset (mp, 0, sizeof (*mp));
+ u16 msg_id =
+ vl_msg_api_get_msg_index ((u8 *) "sw_interface_dump_aa610c27");
+ mp->_vl_msg_id = htons (msg_id);
+ mp->name_filter_valid = 0;
+ rv = vac->send_dump (vac, (u8 *) mp, sizeof (*mp), &out, &out_len);
+ if (!rv)
+ {
+ int i, num;
+ this->mutex->lock (this->mutex);
+ enumerator = this->ifaces->create_enumerator (this->ifaces);
+ num = out_len / sizeof (*rmp);
+ rmp = (vl_api_sw_interface_details_t *) out;
+ for (i = 0; i < num; i++)
+ {
+ bool exists = FALSE;
+ if (i)
+ rmp += 1;
+ while (enumerator->enumerate (enumerator, &entry))
+ {
+ if (entry->index == ntohl (rmp->sw_if_index))
+ {
+ exists = TRUE;
+ break;
+ }
+ }
+ if (!exists)
+ {
+ INIT (entry, .index = ntohl (rmp->sw_if_index),
+ .up = (rmp->flags & IF_STATUS_API_FLAG_LINK_UP) ?
+ TRUE :
+ FALSE,
+ .addrs = linked_list_create (), );
+ memcpy (entry->if_name, rmp->interface_name, 63);
+ this->ifaces->insert_last (this->ifaces, entry);
+ }
+ update_addrs (this, entry);
+ }
+ enumerator->destroy (enumerator);
+ this->mutex->unlock (this->mutex);
+ free (out);
+ }
+ vl_msg_api_free (mp);
+
+ if (!this->events_on)
+ {
+ vl_api_want_interface_events_t *emp;
+ api_main_t *am = vlibapi_get_main ();
+
+ emp = vl_msg_api_alloc (sizeof (*emp));
+ clib_memset (emp, 0, sizeof (*emp));
+ u16 msg_id =
+ vl_msg_api_get_msg_index ((u8 *) "want_interface_events_476f5a08");
+ emp->_vl_msg_id = ntohs (msg_id);
+ emp->enable_disable = 1;
+ emp->pid = ntohl (am->our_pid);
+ rv = vac->register_event (vac, (char *) emp, sizeof (*emp), event_cb,
+ VL_API_SW_INTERFACE_EVENT, this);
+ if (!rv)
+ this->events_on = TRUE;
+ }
+
+ sleep (2);
+ }
+ return NULL;
+}
+
+kernel_vpp_net_t *
+kernel_vpp_net_create ()
+{
+ private_kernel_vpp_net_t *this;
+
+ INIT(this,
+ .public = {
+ .interface = {
+ .get_interface = _get_interface_name,
+ .create_address_enumerator = _create_address_enumerator,
+ .get_source_addr = _get_source_addr,
+ .get_nexthop = _get_nexthop,
+ .add_ip = _add_ip,
+ .del_ip = _del_ip,
+ .add_route = _add_route,
+ .del_route = _del_route,
+ .destroy = _destroy,
+ },
+ },
+ .mutex = mutex_create(MUTEX_TYPE_DEFAULT),
+ .ifaces = linked_list_create(),
+ .events_on = FALSE,
+ );
+
+ this->net_update =
+ thread_create ((thread_main_t) net_update_thread_fn, this);
+
+ return &this->public;
+}