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-rw-r--r--src/plugins/lldp/lldp_input.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/src/plugins/lldp/lldp_input.c b/src/plugins/lldp/lldp_input.c
new file mode 100644
index 00000000000..327ef10f9de
--- /dev/null
+++ b/src/plugins/lldp/lldp_input.c
@@ -0,0 +1,302 @@
+/*
+ * Copyright (c) 2011-2016 Cisco 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.
+ */
+/**
+ * @file
+ * @brief LLDP packet parsing implementation
+ */
+#include <lldp/lldp_node.h>
+#include <lldp/lldp_protocol.h>
+#include <vlibmemory/api.h>
+
+typedef struct
+{
+ u32 hw_if_index;
+ u8 chassis_id_len;
+ u8 chassis_id_subtype;
+ u8 portid_len;
+ u8 portid_subtype;
+ u16 ttl;
+ u8 data[0]; /* this contains both chassis id (chassis_id_len bytes) and port
+ id (portid_len bytes) */
+} lldp_intf_update_t;
+
+static void
+lldp_rpc_update_peer_cb (const lldp_intf_update_t * a)
+{
+ ASSERT (vlib_get_thread_index () == 0);
+
+ lldp_intf_t *n = lldp_get_intf (&lldp_main, a->hw_if_index);
+ if (!n)
+ {
+ /* LLDP turned off for this interface, ignore the update */
+ return;
+ }
+ const u8 *chassis_id = a->data;
+ const u8 *portid = a->data + a->chassis_id_len;
+
+ if (n->chassis_id)
+ {
+ _vec_len (n->chassis_id) = 0;
+ }
+ vec_add (n->chassis_id, chassis_id, a->chassis_id_len);
+ n->chassis_id_subtype = a->chassis_id_subtype;
+ if (n->port_id)
+ {
+ _vec_len (n->port_id) = 0;
+ }
+ vec_add (n->port_id, portid, a->portid_len);
+ n->port_id_subtype = a->portid_subtype;
+ n->ttl = a->ttl;
+ n->last_heard = vlib_time_now (lldp_main.vlib_main);
+}
+
+static void
+lldp_rpc_update_peer (u32 hw_if_index, const u8 * chid, u8 chid_len,
+ u8 chid_subtype, const u8 * portid,
+ u8 portid_len, u8 portid_subtype, u16 ttl)
+{
+ const size_t data_size =
+ sizeof (lldp_intf_update_t) + chid_len + portid_len;
+ u8 data[data_size];
+ lldp_intf_update_t *u = (lldp_intf_update_t *) data;
+ u->hw_if_index = hw_if_index;
+ u->chassis_id_len = chid_len;
+ u->chassis_id_subtype = chid_subtype;
+ u->ttl = ttl;
+ u->portid_len = portid_len;
+ u->portid_subtype = portid_subtype;
+ clib_memcpy (u->data, chid, chid_len);
+ clib_memcpy (u->data + chid_len, portid, portid_len);
+ vl_api_rpc_call_main_thread (lldp_rpc_update_peer_cb, data, data_size);
+}
+
+lldp_tlv_code_t
+lldp_tlv_get_code (const lldp_tlv_t * tlv)
+{
+ return tlv->head.byte1 >> 1;
+}
+
+void
+lldp_tlv_set_code (lldp_tlv_t * tlv, lldp_tlv_code_t code)
+{
+ tlv->head.byte1 = (tlv->head.byte1 & 1) + (code << 1);
+}
+
+u16
+lldp_tlv_get_length (const lldp_tlv_t * tlv)
+{
+ return (((u16) (tlv->head.byte1 & 1)) << 8) + tlv->head.byte2;
+}
+
+void
+lldp_tlv_set_length (lldp_tlv_t * tlv, u16 length)
+{
+ tlv->head.byte2 = length & ((1 << 8) - 1);
+ if (length > (1 << 8) - 1)
+ {
+ tlv->head.byte1 |= 1;
+ }
+ else
+ {
+ tlv->head.byte1 &= (1 << 8) - 2;
+ }
+}
+
+lldp_main_t lldp_main;
+
+static int
+lldp_packet_scan (u32 hw_if_index, const lldp_tlv_t * pkt)
+{
+ const lldp_tlv_t *tlv = pkt;
+
+#define TLV_VIOLATES_PKT_BOUNDARY(pkt, tlv) \
+ (((((u8 *)tlv) + sizeof (lldp_tlv_t)) > ((u8 *)pkt + vec_len (pkt))) || \
+ ((((u8 *)tlv) + lldp_tlv_get_length (tlv)) > ((u8 *)pkt + vec_len (pkt))))
+
+ /* first tlv is always chassis id, followed by port id and ttl tlvs */
+ if (TLV_VIOLATES_PKT_BOUNDARY (pkt, tlv) ||
+ LLDP_TLV_NAME (chassis_id) != lldp_tlv_get_code (tlv))
+ {
+ return LLDP_ERROR_BAD_TLV;
+ }
+
+ u16 l = lldp_tlv_get_length (tlv);
+ if (l < STRUCT_SIZE_OF (lldp_chassis_id_tlv_t, subtype) +
+ LLDP_MIN_CHASS_ID_LEN ||
+ l > STRUCT_SIZE_OF (lldp_chassis_id_tlv_t, subtype) +
+ LLDP_MAX_CHASS_ID_LEN)
+ {
+ return LLDP_ERROR_BAD_TLV;
+ }
+
+ u8 chid_subtype = ((lldp_chassis_id_tlv_t *) tlv)->subtype;
+ u8 *chid = ((lldp_chassis_id_tlv_t *) tlv)->id;
+ u8 chid_len = l - STRUCT_SIZE_OF (lldp_chassis_id_tlv_t, subtype);
+
+ tlv = (lldp_tlv_t *) ((u8 *) tlv + STRUCT_SIZE_OF (lldp_tlv_t, head) + l);
+
+ if (TLV_VIOLATES_PKT_BOUNDARY (pkt, tlv) ||
+ LLDP_TLV_NAME (port_id) != lldp_tlv_get_code (tlv))
+ {
+ return LLDP_ERROR_BAD_TLV;
+ }
+ l = lldp_tlv_get_length (tlv);
+ if (l < STRUCT_SIZE_OF (lldp_port_id_tlv_t, subtype) +
+ LLDP_MIN_PORT_ID_LEN ||
+ l > STRUCT_SIZE_OF (lldp_chassis_id_tlv_t, subtype) +
+ LLDP_MAX_PORT_ID_LEN)
+ {
+ return LLDP_ERROR_BAD_TLV;
+ }
+
+ u8 portid_subtype = ((lldp_port_id_tlv_t *) tlv)->subtype;
+ u8 *portid = ((lldp_port_id_tlv_t *) tlv)->id;
+ u8 portid_len = l - STRUCT_SIZE_OF (lldp_port_id_tlv_t, subtype);
+
+ tlv = (lldp_tlv_t *) ((u8 *) tlv + STRUCT_SIZE_OF (lldp_tlv_t, head) + l);
+
+ if (TLV_VIOLATES_PKT_BOUNDARY (pkt, tlv) ||
+ LLDP_TLV_NAME (ttl) != lldp_tlv_get_code (tlv))
+ {
+ return LLDP_ERROR_BAD_TLV;
+ }
+ l = lldp_tlv_get_length (tlv);
+ if (l != STRUCT_SIZE_OF (lldp_ttl_tlv_t, ttl))
+ {
+ return LLDP_ERROR_BAD_TLV;
+ }
+ u16 ttl = ntohs (((lldp_ttl_tlv_t *) tlv)->ttl);
+ tlv = (lldp_tlv_t *) ((u8 *) tlv + STRUCT_SIZE_OF (lldp_tlv_t, head) + l);
+ while (!TLV_VIOLATES_PKT_BOUNDARY (pkt, tlv) &&
+ LLDP_TLV_NAME (pdu_end) != lldp_tlv_get_code (tlv))
+ {
+ switch (lldp_tlv_get_code (tlv))
+ {
+#define F(num, type, str) \
+ case LLDP_TLV_NAME (type): \
+ /* ignore optional TLV */ \
+ break;
+ foreach_lldp_optional_tlv_type (F);
+#undef F
+ default:
+ return LLDP_ERROR_BAD_TLV;
+ }
+ tlv = (lldp_tlv_t *) ((u8 *) tlv + STRUCT_SIZE_OF (lldp_tlv_t, head) +
+ lldp_tlv_get_length (tlv));
+ }
+ /* last tlv is pdu_end */
+ if (TLV_VIOLATES_PKT_BOUNDARY (pkt, tlv) ||
+ LLDP_TLV_NAME (pdu_end) != lldp_tlv_get_code (tlv) ||
+ 0 != lldp_tlv_get_length (tlv))
+ {
+ return LLDP_ERROR_BAD_TLV;
+ }
+ lldp_rpc_update_peer (hw_if_index, chid, chid_len, chid_subtype, portid,
+ portid_len, portid_subtype, ttl);
+ return LLDP_ERROR_NONE;
+}
+
+lldp_intf_t *
+lldp_get_intf (lldp_main_t * lm, u32 hw_if_index)
+{
+ uword *p = hash_get (lm->intf_by_hw_if_index, hw_if_index);
+
+ if (p)
+ {
+ return pool_elt_at_index (lm->intfs, p[0]);
+ }
+ return NULL;
+}
+
+lldp_intf_t *
+lldp_create_intf (lldp_main_t * lm, u32 hw_if_index)
+{
+
+ uword *p;
+ lldp_intf_t *n;
+ p = hash_get (lm->intf_by_hw_if_index, hw_if_index);
+
+ if (p == 0)
+ {
+ pool_get (lm->intfs, n);
+ clib_memset (n, 0, sizeof (*n));
+ n->hw_if_index = hw_if_index;
+ hash_set (lm->intf_by_hw_if_index, n->hw_if_index, n - lm->intfs);
+ }
+ else
+ {
+ n = pool_elt_at_index (lm->intfs, p[0]);
+ }
+ return n;
+}
+
+/*
+ * lldp input routine
+ */
+lldp_error_t
+lldp_input (vlib_main_t * vm, vlib_buffer_t * b0, u32 bi0)
+{
+ lldp_main_t *lm = &lldp_main;
+ lldp_error_t e;
+
+ /* find our interface */
+ vnet_sw_interface_t *sw_interface = vnet_get_sw_interface (lm->vnet_main,
+ vnet_buffer
+ (b0)->sw_if_index
+ [VLIB_RX]);
+ lldp_intf_t *n = lldp_get_intf (lm, sw_interface->hw_if_index);
+
+ if (!n)
+ {
+ /* lldp disabled on this interface, we're done */
+ return LLDP_ERROR_DISABLED;
+ }
+
+ /* Actually scan the packet */
+ e = lldp_packet_scan (sw_interface->hw_if_index,
+ vlib_buffer_get_current (b0));
+
+ return e;
+}
+
+/*
+ * setup function
+ */
+static clib_error_t *
+lldp_init (vlib_main_t * vm)
+{
+ clib_error_t *error;
+ lldp_main_t *lm = &lldp_main;
+
+ if ((error = vlib_call_init_function (vm, lldp_template_init)))
+ return error;
+
+ lm->vlib_main = vm;
+ lm->vnet_main = vnet_get_main ();
+ lm->msg_tx_hold = 4; /* default value per IEEE 802.1AB-2009 */
+ lm->msg_tx_interval = 30; /* default value per IEEE 802.1AB-2009 */
+
+ return 0;
+}
+
+VLIB_INIT_FUNCTION (lldp_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */