diff options
Diffstat (limited to 'src/vnet/bfd/bfd_udp.c')
| -rw-r--r-- | src/vnet/bfd/bfd_udp.c | 639 |
1 files changed, 639 insertions, 0 deletions
diff --git a/src/vnet/bfd/bfd_udp.c b/src/vnet/bfd/bfd_udp.c new file mode 100644 index 00000000000..3c747d86a10 --- /dev/null +++ b/src/vnet/bfd/bfd_udp.c @@ -0,0 +1,639 @@ +#include <vppinfra/types.h> +#include <vlibmemory/api.h> +#include <vlib/vlib.h> +#include <vlib/buffer.h> +#include <vnet/ip/format.h> +#include <vnet/ethernet/packet.h> +#include <vnet/ip/udp_packet.h> +#include <vnet/ip/lookup.h> +#include <vnet/ip/icmp46_packet.h> +#include <vnet/ip/ip4.h> +#include <vnet/ip/ip6.h> +#include <vnet/ip/udp.h> +#include <vnet/ip/ip6_packet.h> +#include <vnet/adj/adj.h> +#include <vnet/adj/adj_nbr.h> +#include <vnet/bfd/bfd_debug.h> +#include <vnet/bfd/bfd_udp.h> +#include <vnet/bfd/bfd_main.h> +#include <vnet/bfd/bfd_api.h> + +typedef struct +{ + bfd_main_t *bfd_main; + /* hashmap - bfd session index by bfd key - used for CLI/API lookup, where + * discriminator is unknown */ + mhash_t bfd_session_idx_by_bfd_key; +} bfd_udp_main_t; + +static vlib_node_registration_t bfd_udp4_input_node; +static vlib_node_registration_t bfd_udp6_input_node; + +bfd_udp_main_t bfd_udp_main; + +void bfd_udp_transport_to_buffer (vlib_main_t *vm, vlib_buffer_t *b, + bfd_udp_session_t *bus) +{ + udp_header_t *udp; + u16 udp_length, ip_length; + bfd_udp_key_t *key = &bus->key; + + b->flags |= VNET_BUFFER_LOCALLY_ORIGINATED; + if (ip46_address_is_ip4 (&key->local_addr)) + { + ip4_header_t *ip4; + const size_t data_size = sizeof (*ip4) + sizeof (*udp); + vlib_buffer_advance (b, -data_size); + ip4 = vlib_buffer_get_current (b); + udp = (udp_header_t *)(ip4 + 1); + memset (ip4, 0, data_size); + ip4->ip_version_and_header_length = 0x45; + ip4->ttl = 255; + ip4->protocol = IP_PROTOCOL_UDP; + ip4->src_address.as_u32 = key->local_addr.ip4.as_u32; + ip4->dst_address.as_u32 = key->peer_addr.ip4.as_u32; + + udp->src_port = clib_host_to_net_u16 (50000); /* FIXME */ + udp->dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd4); + + /* fix ip length, checksum and udp length */ + ip_length = vlib_buffer_length_in_chain (vm, b); + + ip4->length = clib_host_to_net_u16 (ip_length); + ip4->checksum = ip4_header_checksum (ip4); + + udp_length = ip_length - (sizeof (*ip4)); + udp->length = clib_host_to_net_u16 (udp_length); + } + else + { + BFD_ERR ("not implemented"); + abort (); + } +} + +void bfd_add_udp_transport (vlib_main_t *vm, vlib_buffer_t *b, + bfd_udp_session_t *bus) +{ + vnet_buffer (b)->ip.adj_index[VLIB_RX] = bus->adj_index; + vnet_buffer (b)->ip.adj_index[VLIB_TX] = bus->adj_index; + bfd_udp_transport_to_buffer (vm, b, bus); +} + +static bfd_session_t *bfd_lookup_session (bfd_udp_main_t *bum, + const bfd_udp_key_t *key) +{ + uword *p = mhash_get (&bum->bfd_session_idx_by_bfd_key, key); + if (p) + { + return bfd_find_session_by_idx (bum->bfd_main, *p); + } + return 0; +} + +static vnet_api_error_t +bfd_udp_add_session_internal (bfd_udp_main_t *bum, u32 sw_if_index, + u32 desired_min_tx_us, u32 required_min_rx_us, + u8 detect_mult, const ip46_address_t *local_addr, + const ip46_address_t *peer_addr) +{ + vnet_sw_interface_t *sw_if = + vnet_get_sw_interface (vnet_get_main (), sw_if_index); + /* get a pool entry and if we end up not needing it, give it back */ + bfd_transport_t t = BFD_TRANSPORT_UDP4; + if (!ip46_address_is_ip4 (local_addr)) + { + t = BFD_TRANSPORT_UDP6; + } + bfd_session_t *bs = bfd_get_session (bum->bfd_main, t); + bfd_udp_session_t *bus = &bs->udp; + memset (bus, 0, sizeof (*bus)); + bfd_udp_key_t *key = &bus->key; + key->sw_if_index = sw_if->sw_if_index; + key->local_addr.as_u64[0] = local_addr->as_u64[0]; + key->local_addr.as_u64[1] = local_addr->as_u64[1]; + key->peer_addr.as_u64[0] = peer_addr->as_u64[0]; + key->peer_addr.as_u64[1] = peer_addr->as_u64[1]; + const bfd_session_t *tmp = bfd_lookup_session (bum, key); + if (tmp) + { + BFD_ERR ("duplicate bfd-udp session, existing bs_idx=%d", tmp->bs_idx); + bfd_put_session (bum->bfd_main, bs); + return VNET_API_ERROR_BFD_EEXIST; + } + key->sw_if_index = sw_if->sw_if_index; + mhash_set (&bum->bfd_session_idx_by_bfd_key, key, bs->bs_idx, NULL); + BFD_DBG ("session created, bs_idx=%u, sw_if_index=%d, local=%U, peer=%U", + bs->bs_idx, key->sw_if_index, format_ip46_address, &key->local_addr, + IP46_TYPE_ANY, format_ip46_address, &key->peer_addr, IP46_TYPE_ANY); + if (BFD_TRANSPORT_UDP4 == t) + { + bus->adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP4, VNET_LINK_IP4, + &key->peer_addr, key->sw_if_index); + BFD_DBG ("adj_nbr_add_or_lock(FIB_PROTOCOL_IP4, VNET_LINK_IP4, %U, %d) " + "returns %d", + format_ip46_address, &key->peer_addr, IP46_TYPE_ANY, + key->sw_if_index, bus->adj_index); + } + else + { + bus->adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP6, VNET_LINK_IP6, + &key->peer_addr, key->sw_if_index); + BFD_DBG ("adj_nbr_add_or_lock(FIB_PROTOCOL_IP6, VNET_LINK_IP6, %U, %d) " + "returns %d", + format_ip46_address, &key->peer_addr, IP46_TYPE_ANY, + key->sw_if_index, bus->adj_index); + } + bs->config_desired_min_tx_us = desired_min_tx_us; + bs->required_min_rx_us = required_min_rx_us; + bs->local_detect_mult = detect_mult; + bfd_session_start (bum->bfd_main, bs); + return 0; +} + +static vnet_api_error_t +bfd_udp_validate_api_input (u32 sw_if_index, const ip46_address_t *local_addr, + const ip46_address_t *peer_addr) +{ + vnet_sw_interface_t *sw_if = + vnet_get_sw_interface (vnet_get_main (), sw_if_index); + u8 local_ip_valid = 0; + ip_interface_address_t *ia = NULL; + if (!sw_if) + { + BFD_ERR ("got NULL sw_if"); + return VNET_API_ERROR_INVALID_SW_IF_INDEX; + } + if (ip46_address_is_ip4 (local_addr)) + { + if (!ip46_address_is_ip4 (peer_addr)) + { + BFD_ERR ("IP family mismatch"); + return VNET_API_ERROR_INVALID_ARGUMENT; + } + ip4_main_t *im = &ip4_main; + + /* *INDENT-OFF* */ + foreach_ip_interface_address ( + &im->lookup_main, ia, sw_if_index, 0 /* honor unnumbered */, ({ + ip4_address_t *x = + ip_interface_address_get_address (&im->lookup_main, ia); + if (x->as_u32 == local_addr->ip4.as_u32) + { + /* valid address for this interface */ + local_ip_valid = 1; + break; + } + })); + /* *INDENT-ON* */ + } + else + { + if (ip46_address_is_ip4 (peer_addr)) + { + BFD_ERR ("IP family mismatch"); + return VNET_API_ERROR_INVALID_ARGUMENT; + } + ip6_main_t *im = &ip6_main; + /* *INDENT-OFF* */ + foreach_ip_interface_address ( + &im->lookup_main, ia, sw_if_index, 0 /* honor unnumbered */, ({ + ip6_address_t *x = + ip_interface_address_get_address (&im->lookup_main, ia); + if (local_addr->ip6.as_u64[0] == x->as_u64[0] && + local_addr->ip6.as_u64[1] == x->as_u64[1]) + { + /* valid address for this interface */ + local_ip_valid = 1; + break; + } + })); + /* *INDENT-ON* */ + } + + if (!local_ip_valid) + { + BFD_ERR ("address not found on interface"); + return VNET_API_ERROR_ADDRESS_NOT_FOUND_FOR_INTERFACE; + } + + return 0; +} + +vnet_api_error_t bfd_udp_add_session (u32 sw_if_index, u32 desired_min_tx_us, + u32 required_min_rx_us, u8 detect_mult, + const ip46_address_t *local_addr, + const ip46_address_t *peer_addr) +{ + vnet_api_error_t rv = + bfd_udp_validate_api_input (sw_if_index, local_addr, peer_addr); + if (rv) + { + return rv; + } + if (detect_mult < 1) + { + BFD_ERR ("detect_mult < 1"); + return VNET_API_ERROR_INVALID_ARGUMENT; + } + if (desired_min_tx_us < 1) + { + BFD_ERR ("desired_min_tx_us < 1"); + return VNET_API_ERROR_INVALID_ARGUMENT; + } + return bfd_udp_add_session_internal (&bfd_udp_main, sw_if_index, + desired_min_tx_us, required_min_rx_us, + detect_mult, local_addr, peer_addr); +} + +vnet_api_error_t bfd_udp_del_session (u32 sw_if_index, + const ip46_address_t *local_addr, + const ip46_address_t *peer_addr) +{ + vnet_api_error_t rv = + bfd_udp_validate_api_input (sw_if_index, local_addr, peer_addr); + if (rv) + { + return rv; + } + bfd_udp_main_t *bum = &bfd_udp_main; + vnet_sw_interface_t *sw_if = + vnet_get_sw_interface (vnet_get_main (), sw_if_index); + bfd_udp_key_t key; + memset (&key, 0, sizeof (key)); + key.sw_if_index = sw_if->sw_if_index; + key.local_addr.as_u64[0] = local_addr->as_u64[0]; + key.local_addr.as_u64[1] = local_addr->as_u64[1]; + key.peer_addr.as_u64[0] = peer_addr->as_u64[0]; + key.peer_addr.as_u64[1] = peer_addr->as_u64[1]; + bfd_session_t *tmp = bfd_lookup_session (bum, &key); + if (tmp) + { + BFD_DBG ("free bfd-udp session, bs_idx=%d", tmp->bs_idx); + mhash_unset (&bum->bfd_session_idx_by_bfd_key, &key, NULL); + adj_unlock (tmp->udp.adj_index); + bfd_put_session (bum->bfd_main, tmp); + } + else + { + BFD_ERR ("no such session"); + return VNET_API_ERROR_BFD_NOENT; + } + return 0; +} + +typedef enum { + BFD_UDP_INPUT_NEXT_NORMAL, + BFD_UDP_INPUT_NEXT_REPLY, + BFD_UDP_INPUT_N_NEXT, +} bfd_udp_input_next_t; + +/* Packet counters */ +#define foreach_bfd_udp_error(F) \ + F (NONE, "good bfd packets (processed)") \ + F (BAD, "invalid bfd packets") \ + F (DISABLED, "bfd packets received on disabled interfaces") + +#define F(sym, string) static char BFD_UDP_ERR_##sym##_STR[] = string; +foreach_bfd_udp_error (F); +#undef F + +static char *bfd_udp_error_strings[] = { +#define F(sym, string) BFD_UDP_ERR_##sym##_STR, + foreach_bfd_udp_error (F) +#undef F +}; + +typedef enum { +#define F(sym, str) BFD_UDP_ERROR_##sym, + foreach_bfd_udp_error (F) +#undef F + BFD_UDP_N_ERROR, +} bfd_udp_error_t; + +static void bfd_udp4_find_headers (vlib_buffer_t *b, const ip4_header_t **ip4, + const udp_header_t **udp) +{ + /* sanity check first */ + const i32 start = vnet_buffer (b)->ip.start_of_ip_header; + if (start < 0 && start < sizeof (b->pre_data)) + { + BFD_ERR ("Start of ip header is before pre_data, ignoring"); + *ip4 = NULL; + *udp = NULL; + return; + } + *ip4 = (ip4_header_t *)(b->data + start); + if ((u8 *)*ip4 > (u8 *)vlib_buffer_get_current (b)) + { + BFD_ERR ("Start of ip header is beyond current data, ignoring"); + *ip4 = NULL; + *udp = NULL; + return; + } + *udp = (udp_header_t *)((*ip4) + 1); +} + +static bfd_udp_error_t bfd_udp4_verify_transport (const ip4_header_t *ip4, + const udp_header_t *udp, + const bfd_session_t *bs) +{ + const bfd_udp_session_t *bus = &bs->udp; + const bfd_udp_key_t *key = &bus->key; + if (ip4->src_address.as_u32 != key->peer_addr.ip4.as_u32) + { + BFD_ERR ("IP src addr mismatch, got %U, expected %U", format_ip4_address, + ip4->src_address.as_u32, format_ip4_address, + key->peer_addr.ip4.as_u32); + return BFD_UDP_ERROR_BAD; + } + if (ip4->dst_address.as_u32 != key->local_addr.ip4.as_u32) + { + BFD_ERR ("IP dst addr mismatch, got %U, expected %U", format_ip4_address, + ip4->dst_address.as_u32, format_ip4_address, + key->local_addr.ip4.as_u32); + return BFD_UDP_ERROR_BAD; + } + const u8 expected_ttl = 255; + if (ip4->ttl != expected_ttl) + { + BFD_ERR ("IP unexpected TTL value %d, expected %d", ip4->ttl, + expected_ttl); + return BFD_UDP_ERROR_BAD; + } + if (clib_net_to_host_u16 (udp->src_port) < 49152 || + clib_net_to_host_u16 (udp->src_port) > 65535) + { + BFD_ERR ("Invalid UDP src port %d, out of range <49152,65535>", + udp->src_port); + } + return BFD_UDP_ERROR_NONE; +} + +typedef struct +{ + u32 bs_idx; + bfd_pkt_t pkt; +} bfd_rpc_update_t; + +static void bfd_rpc_update_session_cb (const bfd_rpc_update_t *a) +{ + bfd_consume_pkt (bfd_udp_main.bfd_main, &a->pkt, a->bs_idx); +} + +static void bfd_rpc_update_session (u32 bs_idx, const bfd_pkt_t *pkt) +{ + /* packet length was already verified to be correct by the caller */ + const u32 data_size = sizeof (bfd_rpc_update_t) - + STRUCT_SIZE_OF (bfd_rpc_update_t, pkt) + + pkt->head.length; + u8 data[data_size]; + bfd_rpc_update_t *update = (bfd_rpc_update_t *)data; + update->bs_idx = bs_idx; + clib_memcpy (&update->pkt, pkt, pkt->head.length); + vl_api_rpc_call_main_thread (bfd_rpc_update_session_cb, data, data_size); +} + +static bfd_udp_error_t bfd_udp4_scan (vlib_main_t *vm, vlib_node_runtime_t *rt, + vlib_buffer_t *b, bfd_session_t **bs_out) +{ + const bfd_pkt_t *pkt = vlib_buffer_get_current (b); + if (sizeof (*pkt) > b->current_length) + { + BFD_ERR ( + "Payload size %d too small to hold bfd packet of minimum size %d", + b->current_length, sizeof (*pkt)); + return BFD_UDP_ERROR_BAD; + } + const ip4_header_t *ip4; + const udp_header_t *udp; + bfd_udp4_find_headers (b, &ip4, &udp); + if (!ip4 || !udp) + { + BFD_ERR ("Couldn't find ip4 or udp header"); + return BFD_UDP_ERROR_BAD; + } + if (!bfd_verify_pkt_common (pkt)) + { + return BFD_UDP_ERROR_BAD; + } + bfd_session_t *bs = NULL; + if (pkt->your_disc) + { + BFD_DBG ("Looking up BFD session using discriminator %u", + pkt->your_disc); + bs = bfd_find_session_by_disc (bfd_udp_main.bfd_main, pkt->your_disc); + } + else + { + bfd_udp_key_t key; + memset (&key, 0, sizeof (key)); + key.sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX]; + key.local_addr.ip4.as_u32 = ip4->dst_address.as_u32; + key.peer_addr.ip4.as_u32 = ip4->src_address.as_u32; + BFD_DBG ("Looking up BFD session using key (sw_if_index=%u, local=%U, " + "peer=%U)", + key.sw_if_index, format_ip4_address, key.local_addr.ip4.as_u8, + format_ip4_address, key.peer_addr.ip4.as_u8); + bs = bfd_lookup_session (&bfd_udp_main, &key); + } + if (!bs) + { + BFD_ERR ("BFD session lookup failed - no session matches BFD pkt"); + return BFD_UDP_ERROR_BAD; + } + BFD_DBG ("BFD session found, bs_idx=%u", bs->bs_idx); + if (!bfd_verify_pkt_session (pkt, b->current_length, bs)) + { + return BFD_UDP_ERROR_BAD; + } + bfd_udp_error_t err; + if (BFD_UDP_ERROR_NONE != (err = bfd_udp4_verify_transport (ip4, udp, bs))) + { + return err; + } + bfd_rpc_update_session (bs->bs_idx, pkt); + *bs_out = bs; + return BFD_UDP_ERROR_NONE; +} + +static bfd_udp_error_t bfd_udp6_scan (vlib_main_t *vm, vlib_buffer_t *b) +{ + /* TODO */ + return BFD_UDP_ERROR_BAD; +} + +/* + * Process a frame of bfd packets + * Expect 1 packet / frame + */ +static uword bfd_udp_input (vlib_main_t *vm, vlib_node_runtime_t *rt, + vlib_frame_t *f, int is_ipv6) +{ + u32 n_left_from, *from; + bfd_input_trace_t *t0; + + from = vlib_frame_vector_args (f); /* array of buffer indices */ + n_left_from = f->n_vectors; /* number of buffer indices */ + + while (n_left_from > 0) + { + u32 bi0; + vlib_buffer_t *b0; + u32 next0, error0; + + bi0 = from[0]; + b0 = vlib_get_buffer (vm, bi0); + + bfd_session_t *bs = NULL; + + /* If this pkt is traced, snapshot the data */ + if (b0->flags & VLIB_BUFFER_IS_TRACED) + { + int len; + t0 = vlib_add_trace (vm, rt, b0, sizeof (*t0)); + len = (b0->current_length < sizeof (t0->data)) ? b0->current_length + : sizeof (t0->data); + t0->len = len; + clib_memcpy (t0->data, vlib_buffer_get_current (b0), len); + } + + /* scan this bfd pkt. error0 is the counter index to bmp */ + if (is_ipv6) + { + error0 = bfd_udp6_scan (vm, b0); + } + else + { + error0 = bfd_udp4_scan (vm, rt, b0, &bs); + } + b0->error = rt->errors[error0]; + + next0 = BFD_UDP_INPUT_NEXT_NORMAL; + if (BFD_UDP_ERROR_NONE == error0) + { + /* if everything went fine, check for poll bit, if present, re-use + the buffer and based on (now updated) session parameters, send the + final packet back */ + const bfd_pkt_t *pkt = vlib_buffer_get_current (b0); + if (bfd_pkt_get_poll (pkt)) + { + bfd_send_final (vm, b0, bs); + if (is_ipv6) + { + vlib_node_increment_counter (vm, bfd_udp6_input_node.index, + b0->error, 1); + } + else + { + vlib_node_increment_counter (vm, bfd_udp4_input_node.index, + b0->error, 1); + } + next0 = BFD_UDP_INPUT_NEXT_REPLY; + } + } + vlib_set_next_frame_buffer (vm, rt, next0, bi0); + + from += 1; + n_left_from -= 1; + } + + return f->n_vectors; +} + +static uword bfd_udp4_input (vlib_main_t *vm, vlib_node_runtime_t *rt, + vlib_frame_t *f) +{ + return bfd_udp_input (vm, rt, f, 0); +} + +/* + * bfd input graph node declaration + */ +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (bfd_udp4_input_node, static) = { + .function = bfd_udp4_input, + .name = "bfd-udp4-input", + .vector_size = sizeof (u32), + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = BFD_UDP_N_ERROR, + .error_strings = bfd_udp_error_strings, + + .format_trace = bfd_input_format_trace, + + .n_next_nodes = BFD_UDP_INPUT_N_NEXT, + .next_nodes = + { + [BFD_UDP_INPUT_NEXT_NORMAL] = "error-drop", + [BFD_UDP_INPUT_NEXT_REPLY] = "ip4-lookup", + }, +}; +/* *INDENT-ON* */ + +static uword bfd_udp6_input (vlib_main_t *vm, vlib_node_runtime_t *rt, + vlib_frame_t *f) +{ + return bfd_udp_input (vm, rt, f, 1); +} + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (bfd_udp6_input_node, static) = { + .function = bfd_udp6_input, + .name = "bfd-udp6-input", + .vector_size = sizeof (u32), + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = BFD_UDP_N_ERROR, + .error_strings = bfd_udp_error_strings, + + .format_trace = bfd_input_format_trace, + + .n_next_nodes = BFD_UDP_INPUT_N_NEXT, + .next_nodes = + { + [BFD_UDP_INPUT_NEXT_NORMAL] = "error-drop", + [BFD_UDP_INPUT_NEXT_REPLY] = "ip6-lookup", + }, +}; +/* *INDENT-ON* */ + +static clib_error_t *bfd_sw_interface_up_down (vnet_main_t *vnm, + u32 sw_if_index, u32 flags) +{ + // vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index); + if (!(flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)) + { + /* TODO */ + } + return 0; +} + +VNET_SW_INTERFACE_ADMIN_UP_DOWN_FUNCTION (bfd_sw_interface_up_down); + +static clib_error_t *bfd_hw_interface_up_down (vnet_main_t *vnm, + u32 hw_if_index, u32 flags) +{ + if (flags & VNET_HW_INTERFACE_FLAG_LINK_UP) + { + /* TODO */ + } + return 0; +} + +VNET_HW_INTERFACE_LINK_UP_DOWN_FUNCTION (bfd_hw_interface_up_down); + +/* + * setup function + */ +static clib_error_t *bfd_udp_init (vlib_main_t *vm) +{ + mhash_init (&bfd_udp_main.bfd_session_idx_by_bfd_key, sizeof (uword), + sizeof (bfd_udp_key_t)); + bfd_udp_main.bfd_main = &bfd_main; + udp_register_dst_port (vm, UDP_DST_PORT_bfd4, bfd_udp4_input_node.index, 1); + udp_register_dst_port (vm, UDP_DST_PORT_bfd6, bfd_udp6_input_node.index, 0); + return 0; +} + +VLIB_INIT_FUNCTION (bfd_udp_init); |