diff options
author | Dave Barach <dave@barachs.net> | 2018-03-10 14:57:00 -0500 |
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committer | Dave Barach <dave@barachs.net> | 2018-03-10 15:27:58 -0500 |
commit | aaacfbc5b15b0653489ad2e80db48151a4375ece (patch) | |
tree | cbe4228c1e674116563229e52bc5e9d73229b5af /src/plugins/cdp/cdp_periodic.c | |
parent | fde0929d9362eac5c416f658e1d2031d01a02337 (diff) |
Move the vnet cdp protocol implementation to a plugin
Add a binary API and debug cli to enable/disable cdp. cdp is disabled
by default.
Change-Id: I307c7e38dfda38e36ff3325f65de7036c34d89b1
Signed-off-by: Dave Barach <dave@barachs.net>
Diffstat (limited to 'src/plugins/cdp/cdp_periodic.c')
-rw-r--r-- | src/plugins/cdp/cdp_periodic.c | 515 |
1 files changed, 515 insertions, 0 deletions
diff --git a/src/plugins/cdp/cdp_periodic.c b/src/plugins/cdp/cdp_periodic.c new file mode 100644 index 00000000000..c67af00c7a5 --- /dev/null +++ b/src/plugins/cdp/cdp_periodic.c @@ -0,0 +1,515 @@ +/* + * Copyright (c) 2011-2018 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. + */ +#include <cdp/cdp.h> +#include <vppinfra/hash.h> +#include <vnet/unix/pcap.h> +#include <vnet/srp/srp.h> +#include <vnet/ppp/ppp.h> +#include <vnet/hdlc/hdlc.h> +#include <vnet/srp/packet.h> + +/* + * Generate a set of specific CDP TLVs. + * + * $$$ eventually these need to fish better data from + * other data structures; e.g. the hostname, software version info + * etc. + */ + +static void +add_device_name_tlv (vnet_hw_interface_t * hw, u8 ** t0p) +{ + cdp_tlv_t *t = (cdp_tlv_t *) * t0p; + + t->t = htons (CDP_TLV_device_name); + t->l = htons (3 + sizeof (*t)); + clib_memcpy (&t->v, "VPP", 3); + + *t0p += ntohs (t->l); +} + +static void +add_port_id_tlv (vnet_hw_interface_t * hw, u8 ** t0p) +{ + cdp_tlv_t *t = (cdp_tlv_t *) * t0p; + + t->t = htons (CDP_TLV_port_id); + t->l = htons (vec_len (hw->name) + sizeof (*t)); + clib_memcpy (&t->v, hw->name, vec_len (hw->name)); + *t0p += ntohs (t->l); +} + +static void +add_version_tlv (vnet_hw_interface_t * hw, u8 ** t0p) +{ + cdp_tlv_t *t = (cdp_tlv_t *) * t0p; + + t->t = htons (CDP_TLV_version); + t->l = htons (12 + sizeof (*t)); + clib_memcpy (&t->v, "VPP Software", 12); + *t0p += ntohs (t->l); +} + +static void +add_platform_tlv (vnet_hw_interface_t * hw, u8 ** t0p) +{ + cdp_tlv_t *t = (cdp_tlv_t *) * t0p; + + t->t = htons (CDP_TLV_platform); + t->l = htons (2 + sizeof (*t)); + clib_memcpy (&t->v, "SW", 2); + *t0p += ntohs (t->l); +} + +static void +add_capability_tlv (vnet_hw_interface_t * hw, u8 ** t0p) +{ + cdp_tlv_t *t = (cdp_tlv_t *) * t0p; + u32 capabilities; + + t->t = htons (CDP_TLV_capabilities); + t->l = htons (4 + sizeof (*t)); + capabilities = CDP_ROUTER_DEVICE; + capabilities = htonl (capabilities); + clib_memcpy (&t->v, &capabilities, sizeof (capabilities)); + *t0p += ntohs (t->l); +} + +static void +add_tlvs (cdp_main_t * cm, vnet_hw_interface_t * hw, u8 ** t0p) +{ + add_device_name_tlv (hw, t0p); + add_port_id_tlv (hw, t0p); + add_version_tlv (hw, t0p); + add_platform_tlv (hw, t0p); + add_capability_tlv (hw, t0p); +} + +/* + * send a cdp pkt on an ethernet interface + */ +static void +send_ethernet_hello (cdp_main_t * cm, cdp_neighbor_t * n, int count) +{ + u32 *to_next; + ethernet_llc_snap_and_cdp_header_t *h0; + vnet_hw_interface_t *hw; + u32 bi0; + vlib_buffer_t *b0; + u8 *t0; + u16 checksum; + int nbytes_to_checksum; + int i; + vlib_frame_t *f; + vlib_main_t *vm = cm->vlib_main; + vnet_main_t *vnm = cm->vnet_main; + + for (i = 0; i < count; i++) + { + /* + * see cdp_periodic_init() to understand what's already painted + * into the buffer by the packet template mechanism + */ + h0 = vlib_packet_template_get_packet + (vm, &cm->packet_templates[n->packet_template_index], &bi0); + + if (!h0) + break; + + /* Add the interface's ethernet source address */ + hw = vnet_get_sup_hw_interface (vnm, n->sw_if_index); + + clib_memcpy (h0->ethernet.src_address, hw->hw_address, + vec_len (hw->hw_address)); + + t0 = (u8 *) & h0->cdp.data; + + /* add TLVs */ + add_tlvs (cm, hw, &t0); + + /* add the cdp packet checksum */ + nbytes_to_checksum = t0 - (u8 *) & h0->cdp; + checksum = cdp_checksum (&h0->cdp, nbytes_to_checksum); + h0->cdp.checksum = htons (checksum); + + /* Set the outbound packet length */ + b0 = vlib_get_buffer (vm, bi0); + b0->current_length = nbytes_to_checksum + sizeof (*h0) + - sizeof (cdp_hdr_t); + + /* And the outbound interface */ + vnet_buffer (b0)->sw_if_index[VLIB_TX] = hw->sw_if_index; + + /* Set the 802.3 ethernet length */ + h0->ethernet.len = htons (b0->current_length + - sizeof (ethernet_802_3_header_t)); + + /* And output the packet on the correct interface */ + f = vlib_get_frame_to_node (vm, hw->output_node_index); + to_next = vlib_frame_vector_args (f); + to_next[0] = bi0; + f->n_vectors = 1; + + vlib_put_frame_to_node (vm, hw->output_node_index, f); + n->last_sent = vlib_time_now (vm); + } +} + +/* + * send a cdp pkt on an hdlc interface + */ +static void +send_hdlc_hello (cdp_main_t * cm, cdp_neighbor_t * n, int count) +{ + u32 *to_next; + hdlc_and_cdp_header_t *h0; + vnet_hw_interface_t *hw; + u32 bi0; + vlib_buffer_t *b0; + u8 *t0; + u16 checksum; + int nbytes_to_checksum; + int i; + vlib_frame_t *f; + vlib_main_t *vm = cm->vlib_main; + vnet_main_t *vnm = cm->vnet_main; + + for (i = 0; i < count; i++) + { + /* + * see cdp_periodic_init() to understand what's already painted + * into the buffer by the packet template mechanism + */ + h0 = vlib_packet_template_get_packet + (vm, &cm->packet_templates[n->packet_template_index], &bi0); + + hw = vnet_get_sup_hw_interface (vnm, n->sw_if_index); + + t0 = (u8 *) & h0->cdp.data; + + /* add TLVs */ + add_tlvs (cm, hw, &t0); + + /* add the cdp packet checksum */ + nbytes_to_checksum = t0 - (u8 *) & h0->cdp; + checksum = cdp_checksum (&h0->cdp, nbytes_to_checksum); + h0->cdp.checksum = htons (checksum); + + /* Set the outbound packet length */ + b0 = vlib_get_buffer (vm, bi0); + b0->current_length = nbytes_to_checksum + sizeof (*h0) + - sizeof (cdp_hdr_t); + + /* And output the packet on the correct interface */ + f = vlib_get_frame_to_node (vm, hw->output_node_index); + to_next = vlib_frame_vector_args (f); + to_next[0] = bi0; + f->n_vectors = 1; + + vlib_put_frame_to_node (vm, hw->output_node_index, f); + n->last_sent = vlib_time_now (vm); + } +} + +/* + * send a cdp pkt on an srp interface + */ +static void +send_srp_hello (cdp_main_t * cm, cdp_neighbor_t * n, int count) +{ + u32 *to_next; + srp_and_cdp_header_t *h0; + vnet_hw_interface_t *hw; + u32 bi0; + vlib_buffer_t *b0; + u8 *t0; + u16 checksum; + int nbytes_to_checksum; + int i; + vlib_frame_t *f; + vlib_main_t *vm = cm->vlib_main; + vnet_main_t *vnm = cm->vnet_main; + + for (i = 0; i < count; i++) + { + /* + * see cdp_periodic_init() to understand what's already painted + * into the buffer by the packet template mechanism + */ + h0 = vlib_packet_template_get_packet + (vm, &cm->packet_templates[n->packet_template_index], &bi0); + + hw = vnet_get_sup_hw_interface (vnm, n->sw_if_index); + + t0 = (u8 *) & h0->cdp.data; + + /* add TLVs */ + add_tlvs (cm, hw, &t0); + + /* Add the interface's ethernet source address */ + clib_memcpy (h0->ethernet.src_address, hw->hw_address, + vec_len (hw->hw_address)); + + /* add the cdp packet checksum */ + nbytes_to_checksum = t0 - (u8 *) & h0->cdp; + checksum = cdp_checksum (&h0->cdp, nbytes_to_checksum); + h0->cdp.checksum = htons (checksum); + + /* Set the outbound packet length */ + b0 = vlib_get_buffer (vm, bi0); + b0->current_length = nbytes_to_checksum + sizeof (*h0) + - sizeof (cdp_hdr_t); + + /* And output the packet on the correct interface */ + f = vlib_get_frame_to_node (vm, hw->output_node_index); + to_next = vlib_frame_vector_args (f); + to_next[0] = bi0; + f->n_vectors = 1; + + vlib_put_frame_to_node (vm, hw->output_node_index, f); + n->last_sent = vlib_time_now (vm); + } +} + +/* + * Decide which cdp packet template to use + */ +static int +pick_packet_template (cdp_main_t * cm, cdp_neighbor_t * n) +{ + n->packet_template_index = CDP_PACKET_TEMPLATE_ETHERNET; + + return 0; +} + +/* Send a cdp neighbor announcement */ +static void +send_hello (cdp_main_t * cm, cdp_neighbor_t * n, int count) +{ + if (n->packet_template_index == (u8) ~ 0) + { + /* If we don't know how to talk to this peer, don't try again */ + if (pick_packet_template (cm, n)) + { + n->last_sent = 1e70; + return; + } + } + + switch (n->packet_template_index) + { + case CDP_PACKET_TEMPLATE_ETHERNET: + send_ethernet_hello (cm, n, count); + break; + + case CDP_PACKET_TEMPLATE_HDLC: + send_hdlc_hello (cm, n, count); + break; + + case CDP_PACKET_TEMPLATE_SRP: + send_srp_hello (cm, n, count); + break; + + default: + ASSERT (0); + } + n->last_sent = vlib_time_now (cm->vlib_main); +} + +static void +delete_neighbor (cdp_main_t * cm, cdp_neighbor_t * n, int want_broadcast) +{ + hash_unset (cm->neighbor_by_sw_if_index, n->sw_if_index); + vec_free (n->device_name); + vec_free (n->version); + vec_free (n->port_id); + vec_free (n->platform); + vec_free (n->last_rx_pkt); + pool_put (cm->neighbors, n); +} + +void +cdp_periodic (vlib_main_t * vm) +{ + cdp_main_t *cm = &cdp_main; + cdp_neighbor_t *n; + f64 now = vlib_time_now (vm); + vnet_sw_interface_t *sw; + static u32 *delete_list = 0; + int i; + static cdp_neighbor_t **n_list = 0; + + /* *INDENT-OFF* */ + pool_foreach (n, cm->neighbors, + ({ + vec_add1 (n_list, n); + })); + /* *INDENT-ON* */ + + /* Across all cdp neighbors known to the system */ + for (i = 0; i < vec_len (n_list); i++) + { + n = n_list[i]; + + /* "no cdp run" provisioned on the interface? */ + if (n->disabled == 1) + continue; + + sw = vnet_get_sw_interface (cm->vnet_main, n->sw_if_index); + + /* Interface shutdown or rx timeout? */ + if (!(sw->flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) + || (now > (n->last_heard + (f64) n->ttl_in_seconds))) + /* add to list of neighbors to delete */ + vec_add1 (delete_list, n - cm->neighbors); + else if (n->last_sent == 0.0) + /* First time, send 3 hellos */ + send_hello (cm, n, 3 /* three to begin with */ ); + else if (now > (n->last_sent + (((f64) n->ttl_in_seconds) / 6.0))) + /* Normal keepalive, send one */ + send_hello (cm, n, 1 /* one as a keepalive */ ); + } + + for (i = 0; i < vec_len (delete_list); i++) + { + n = vec_elt_at_index (cm->neighbors, delete_list[i]); + delete_neighbor (cm, n, 1); + } + if (delete_list) + _vec_len (delete_list) = 0; + if (n_list) + _vec_len (n_list) = 0; +} + +static clib_error_t * +cdp_periodic_init (vlib_main_t * vm) +{ + cdp_main_t *cm = &cdp_main; + + /* Create the ethernet cdp hello packet template */ + { + ethernet_llc_snap_and_cdp_header_t h; + + memset (&h, 0, sizeof (h)); + + /* Send to 01:00:0c:cc:cc */ + h.ethernet.dst_address[0] = 0x01; + /* h.ethernet.dst_address[1] = 0x00; (memset) */ + h.ethernet.dst_address[2] = 0x0C; + h.ethernet.dst_address[3] = 0xCC; + h.ethernet.dst_address[4] = 0xCC; + h.ethernet.dst_address[5] = 0xCC; + + /* leave src address blank (fill in at send time) */ + + /* leave length blank (fill in at send time) */ + + /* LLC */ + h.llc.dst_sap = h.llc.src_sap = 0xAA; /* SNAP */ + h.llc.control = 0x03; /* UI (no extended control bytes) */ + + /* SNAP */ + /* h.snap.oui[0] = 0x00; (memset) */ + /* h.snap.oui[1] = 0x00; (memset) */ + h.snap.oui[2] = 0x0C; /* Cisco = 0x00000C */ + h.snap.protocol = htons (0x2000); /* CDP = 0x2000 */ + + /* CDP */ + h.cdp.version = 2; + h.cdp.ttl = 180; + + vlib_packet_template_init + (vm, &cm->packet_templates[CDP_PACKET_TEMPLATE_ETHERNET], + /* data */ &h, + sizeof (h), + /* alloc chunk size */ 8, + "cdp-ethernet"); + } + +#if 0 /* retain for reference */ + + /* Create the hdlc cdp hello packet template */ + { + hdlc_and_cdp_header_t h; + + memset (&h, 0, sizeof (h)); + + h.hdlc.address = 0x0f; + /* h.hdlc.control = 0; (memset) */ + h.hdlc.protocol = htons (0x2000); /* CDP = 0x2000 */ + + /* CDP */ + h.cdp.version = 2; + h.cdp.ttl = 180; + + vlib_packet_template_init + (vm, &cm->packet_templates[CDP_PACKET_TEMPLATE_HDLC], + /* data */ &h, + sizeof (h), + /* alloc chunk size */ 8, + "cdp-hdlc"); + } + + /* Create the srp cdp hello packet template */ + { + srp_and_cdp_header_t h; + + memset (&h, 0, sizeof (h)); + + /* Send to 01:00:0c:cc:cc */ + h.ethernet.dst_address[0] = 0x01; + /* h.ethernet.dst_address[1] = 0x00; (memset) */ + h.ethernet.dst_address[2] = 0x0C; + h.ethernet.dst_address[3] = 0xCC; + h.ethernet.dst_address[4] = 0xCC; + h.ethernet.dst_address[5] = 0xCC; + + /* leave src address blank (fill in at send time) */ + + /* The srp header is filled in at xmt */ + h.srp.ttl = 1; + h.srp.priority = 7; + h.srp.mode = SRP_MODE_data; + srp_header_compute_parity (&h.srp); + + /* Inner ring and parity will be set at send time */ + + h.ethernet.type = htons (0x2000); /* CDP = 0x2000 */ + + /* CDP */ + h.cdp.version = 2; + h.cdp.ttl = 180; + + vlib_packet_template_init + (vm, &cm->packet_templates[CDP_PACKET_TEMPLATE_SRP], + /* data */ &h, + sizeof (h), + /* alloc chunk size */ 8, + "cdp-srp"); + } +#endif + + return 0; +} + +VLIB_INIT_FUNCTION (cdp_periodic_init); + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |