From 239790fd91b3f62e5eda1042a97f9216fe59856e Mon Sep 17 00:00:00 2001 From: Klement Sekera Date: Thu, 16 Feb 2017 10:53:53 +0100 Subject: BFD: echo function Change-Id: Ib1e301d62b687d4e42434239e7cd412065c28da0 Signed-off-by: Klement Sekera --- src/vnet/bfd/bfd_udp.c | 286 ++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 225 insertions(+), 61 deletions(-) (limited to 'src/vnet/bfd/bfd_udp.c') diff --git a/src/vnet/bfd/bfd_udp.c b/src/vnet/bfd/bfd_udp.c index 8519009d..146faad6 100644 --- a/src/vnet/bfd/bfd_udp.c +++ b/src/vnet/bfd/bfd_udp.c @@ -27,6 +27,9 @@ #include #include #include +#include +#include +#include #include #include #include @@ -38,6 +41,12 @@ typedef struct /* hashmap - bfd session index by bfd key - used for CLI/API lookup, where * discriminator is unknown */ mhash_t bfd_session_idx_by_bfd_key; + /* convenience variable */ + vnet_main_t *vnet_main; + /* flag indicating whether echo_source_sw_if_index holds a valid value */ + int echo_source_is_set; + /* loopback interface used to get echo source ip */ + u32 echo_source_sw_if_index; } bfd_udp_main_t; static vlib_node_registration_t bfd_udp4_input_node; @@ -47,6 +56,80 @@ static vlib_node_registration_t bfd_udp_echo6_input_node; bfd_udp_main_t bfd_udp_main; +vnet_api_error_t +bfd_udp_set_echo_source (u32 sw_if_index) +{ + vnet_sw_interface_t *sw_if = + vnet_get_sw_interface_safe (bfd_udp_main.vnet_main, + bfd_udp_main.echo_source_sw_if_index); + if (sw_if) + { + bfd_udp_main.echo_source_sw_if_index = sw_if_index; + bfd_udp_main.echo_source_is_set = 1; + return 0; + } + return VNET_API_ERROR_BFD_ENOENT; +} + +vnet_api_error_t +bfd_udp_del_echo_source (u32 sw_if_index) +{ + bfd_udp_main.echo_source_sw_if_index = ~0; + bfd_udp_main.echo_source_is_set = 0; + return 0; +} + +int +bfd_udp_is_echo_available (bfd_transport_e transport) +{ + if (!bfd_udp_main.echo_source_is_set) + { + return 0; + } + /* + * for the echo to work, we need a loopback interface with at least one + * address with netmask length at most 31 (ip4) or 127 (ip6) so that we can + * pick an unused address from that subnet + */ + vnet_sw_interface_t *sw_if = + vnet_get_sw_interface_safe (bfd_udp_main.vnet_main, + bfd_udp_main.echo_source_sw_if_index); + if (sw_if && sw_if->flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) + { + if (BFD_TRANSPORT_UDP4 == transport) + { + ip4_main_t *im = &ip4_main; + ip_interface_address_t *ia = NULL; + /* *INDENT-OFF* */ + foreach_ip_interface_address (&im->lookup_main, ia, + bfd_udp_main.echo_source_sw_if_index, + 0 /* honor unnumbered */, ({ + if (ia->address_length <= 31) + { + return 1; + } + })); + /* *INDENT-ON* */ + } + else if (BFD_TRANSPORT_UDP6 == transport) + { + ip6_main_t *im = &ip6_main; + ip_interface_address_t *ia = NULL; + /* *INDENT-OFF* */ + foreach_ip_interface_address (&im->lookup_main, ia, + bfd_udp_main.echo_source_sw_if_index, + 0 /* honor unnumbered */, ({ + if (ia->address_length <= 127) + { + return 1; + } + })); + /* *INDENT-ON* */ + } + } + return 0; +} + static u16 bfd_udp_bs_idx_to_sport (u32 bs_idx) { @@ -61,9 +144,78 @@ bfd_udp_bs_idx_to_sport (u32 bs_idx) return 49152 + bs_idx % (65535 - 49152 + 1); } -void +static void +lol () +{ +} + +int +bfd_udp_get_echo_src_ip4 (ip4_address_t * addr) +{ + if (!bfd_udp_main.echo_source_is_set) + { + BFD_ERR ("cannot find ip4 address, echo source not set"); + return 0; + } + ip_interface_address_t *ia = NULL; + ip4_main_t *im = &ip4_main; + + /* *INDENT-OFF* */ + foreach_ip_interface_address ( + &im->lookup_main, ia, bfd_udp_main.echo_source_sw_if_index, + 0 /* honor unnumbered */, ({ + ip4_address_t *x = + ip_interface_address_get_address (&im->lookup_main, ia); + if (ia->address_length <= 31) + { + addr->as_u32 = clib_host_to_net_u32 (x->as_u32); + /* + * flip the last bit to get a different address, might be network, + * we don't care ... + */ + addr->as_u32 ^= 1; + addr->as_u32 = clib_net_to_host_u32 (addr->as_u32); + return 1; + } + })); + /* *INDENT-ON* */ + BFD_ERR ("cannot find ip4 address, no usable address found"); + return 0; +} + +int +bfd_udp_get_echo_src_ip6 (ip6_address_t * addr) +{ + if (!bfd_udp_main.echo_source_is_set) + { + BFD_ERR ("cannot find ip6 address, echo source not set"); + return 0; + } + ip_interface_address_t *ia = NULL; + ip6_main_t *im = &ip6_main; + + /* *INDENT-OFF* */ + foreach_ip_interface_address ( + &im->lookup_main, ia, bfd_udp_main.echo_source_sw_if_index, + 0 /* honor unnumbered */, ({ + ip6_address_t *x = + ip_interface_address_get_address (&im->lookup_main, ia); + if (ia->address_length <= 127) + { + *addr = *x; + addr->as_u8[15] ^= 1; /* flip the last bit of the address */ + lol (); + return 1; + } + })); + /* *INDENT-ON* */ + BFD_ERR ("cannot find ip6 address, no usable address found"); + return 0; +} + +int bfd_add_udp4_transport (vlib_main_t * vm, vlib_buffer_t * b, - const bfd_session_t * bs) + const bfd_session_t * bs, int is_echo) { const bfd_udp_session_t *bus = &bs->udp; const bfd_udp_key_t *key = &bus->key; @@ -83,12 +235,24 @@ bfd_add_udp4_transport (vlib_main_t * vm, vlib_buffer_t * b, headers->ip4.ip_version_and_header_length = 0x45; headers->ip4.ttl = 255; headers->ip4.protocol = IP_PROTOCOL_UDP; - headers->ip4.src_address.as_u32 = key->local_addr.ip4.as_u32; - headers->ip4.dst_address.as_u32 = key->peer_addr.ip4.as_u32; - headers->udp.src_port = clib_host_to_net_u16 (bfd_udp_bs_idx_to_sport (bs->bs_idx)); - headers->udp.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd4); + if (is_echo) + { + int rv; + if (!(rv = bfd_udp_get_echo_src_ip4 (&headers->ip4.src_address))) + { + return rv; + } + headers->ip4.dst_address.as_u32 = key->local_addr.ip4.as_u32; + headers->udp.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd_echo4); + } + else + { + headers->ip4.src_address.as_u32 = key->local_addr.ip4.as_u32; + headers->ip4.dst_address.as_u32 = key->peer_addr.ip4.as_u32; + headers->udp.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd4); + } /* fix ip length, checksum and udp length */ const u16 ip_length = vlib_buffer_length_in_chain (vm, b); @@ -98,11 +262,12 @@ bfd_add_udp4_transport (vlib_main_t * vm, vlib_buffer_t * b, const u16 udp_length = ip_length - (sizeof (headers->ip4)); headers->udp.length = clib_host_to_net_u16 (udp_length); + return 1; } -void +int bfd_add_udp6_transport (vlib_main_t * vm, vlib_buffer_t * b, - const bfd_session_t * bs) + const bfd_session_t * bs, int is_echo) { const bfd_udp_session_t *bus = &bs->udp; const bfd_udp_key_t *key = &bus->key; @@ -123,14 +288,28 @@ bfd_add_udp6_transport (vlib_main_t * vm, vlib_buffer_t * b, clib_host_to_net_u32 (0x6 << 28); headers->ip6.hop_limit = 255; headers->ip6.protocol = IP_PROTOCOL_UDP; - clib_memcpy (&headers->ip6.src_address, &key->local_addr.ip6, - sizeof (headers->ip6.src_address)); - clib_memcpy (&headers->ip6.dst_address, &key->peer_addr.ip6, - sizeof (headers->ip6.dst_address)); - headers->udp.src_port = clib_host_to_net_u16 (bfd_udp_bs_idx_to_sport (bs->bs_idx)); - headers->udp.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd6); + if (is_echo) + { + int rv; + if (!(rv = bfd_udp_get_echo_src_ip6 (&headers->ip6.src_address))) + { + return rv; + } + clib_memcpy (&headers->ip6.dst_address, &key->local_addr.ip6, + sizeof (headers->ip6.dst_address)); + + headers->udp.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd_echo6); + } + else + { + clib_memcpy (&headers->ip6.src_address, &key->local_addr.ip6, + sizeof (headers->ip6.src_address)); + clib_memcpy (&headers->ip6.dst_address, &key->peer_addr.ip6, + sizeof (headers->ip6.dst_address)); + headers->udp.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd6); + } /* fix ip payload length and udp length */ const u16 udp_length = @@ -147,6 +326,7 @@ bfd_add_udp6_transport (vlib_main_t * vm, vlib_buffer_t * b, { headers->udp.checksum = 0xffff; } + return 1; } static bfd_session_t * @@ -182,12 +362,17 @@ bfd_udp_add_session_internal (bfd_udp_main_t * bum, u32 sw_if_index, bfd_session_t ** bs_out) { /* get a pool entry and if we end up not needing it, give it back */ - bfd_transport_t t = BFD_TRANSPORT_UDP4; + bfd_transport_e 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); + if (!bs) + { + bfd_put_session (bum->bfd_main, bs); + return VNET_API_ERROR_BFD_EAGAIN; + } bfd_udp_session_t *bus = &bs->udp; memset (bus, 0, sizeof (*bus)); bfd_udp_key_t *key = &bus->key; @@ -213,6 +398,21 @@ bfd_udp_add_session_internal (bfd_udp_main_t * bum, u32 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); + + fib_prefix_t fib_prefix; + memset (&fib_prefix, 0, sizeof (fib_prefix)); + fib_prefix.fp_len = 0; + fib_prefix.fp_proto = FIB_PROTOCOL_IP4; + fib_prefix.fp_addr = key->local_addr; + u32 fib_index = fib_table_find (FIB_PROTOCOL_IP4, 0); /* FIXME table id 0? */ + dpo_id_t dpo = DPO_INVALID; + dpo_proto_t dproto; + dproto = fib_proto_to_dpo (fib_prefix.fp_proto); + receive_dpo_add_or_lock (dproto, ~0, NULL, &dpo); + fib_table_entry_special_dpo_update (fib_index, &fib_prefix, + FIB_SOURCE_API, + FIB_ENTRY_FLAG_LOCAL, &dpo); + dpo_reset (&dpo); } else { @@ -234,7 +434,7 @@ bfd_udp_validate_api_input (u32 sw_if_index, const ip46_address_t * peer_addr) { vnet_sw_interface_t *sw_if = - vnet_get_sw_interface (vnet_get_main (), sw_if_index); + vnet_get_sw_interface_safe (bfd_udp_main.vnet_main, sw_if_index); u8 local_ip_valid = 0; ip_interface_address_t *ia = NULL; if (!sw_if) @@ -1001,7 +1201,8 @@ bfd_udp_input (vlib_main_t * vm, vlib_node_runtime_t * rt, const bfd_pkt_t *pkt = vlib_buffer_get_current (b0); if (bfd_pkt_get_poll (pkt)) { - bfd_init_final_control_frame (vm, b0, bs); + bfd_init_final_control_frame (vm, b0, bfd_udp_main.bfd_main, + bs); if (is_ipv6) { vlib_node_increment_counter (vm, bfd_udp6_input_node.index, @@ -1081,44 +1282,6 @@ VLIB_REGISTER_NODE (bfd_udp6_input_node, static) = { }; /* *INDENT-ON* */ -/** - * @brief swap the source and destination IP addresses in the packet - */ -static int -bfd_echo_address_swap (vlib_buffer_t * b, int is_ipv6) -{ - udp_header_t *dummy = NULL; - if (is_ipv6) - { - ip6_header_t *ip6 = NULL; - bfd_udp6_find_headers (b, &ip6, &dummy); - if (!ip6) - { - return 0; - } - ip6_address_t tmp = ip6->dst_address; - ip6->dst_address = ip6->src_address; - ip6->src_address = tmp; - vlib_buffer_advance (b, - (u8 *) ip6 - (u8 *) vlib_buffer_get_current (b)); - } - else - { - ip4_header_t *ip4 = NULL; - bfd_udp4_find_headers (b, &ip4, &dummy); - if (!ip4) - { - return 0; - } - ip4_address_t tmp = ip4->dst_address; - ip4->dst_address = ip4->src_address; - ip4->src_address = tmp; - vlib_buffer_advance (b, - (u8 *) ip4 - (u8 *) vlib_buffer_get_current (b)); - } - return 1; -} - /* * Process a frame of bfd echo packets * Expect 1 packet / frame @@ -1153,7 +1316,12 @@ bfd_udp_echo_input (vlib_main_t * vm, vlib_node_runtime_t * rt, clib_memcpy (t0->data, vlib_buffer_get_current (b0), len); } - if (bfd_echo_address_swap (b0, is_ipv6)) + if (bfd_consume_echo_pkt (bfd_udp_main.bfd_main, b0)) + { + b0->error = rt->errors[BFD_UDP_ERROR_NONE]; + next0 = BFD_UDP_INPUT_NEXT_NORMAL; + } + else { /* loop back the packet */ b0->error = rt->errors[BFD_UDP_ERROR_NONE]; @@ -1169,11 +1337,6 @@ bfd_udp_echo_input (vlib_main_t * vm, vlib_node_runtime_t * rt, } next0 = BFD_UDP_INPUT_NEXT_REPLY; } - else - { - b0->error = rt->errors[BFD_UDP_ERROR_BAD]; - next0 = BFD_UDP_INPUT_NEXT_NORMAL; - } vlib_set_next_frame_buffer (vm, rt, next0, bi0); @@ -1294,6 +1457,7 @@ 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; + bfd_udp_main.vnet_main = vnet_get_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); udp_register_dst_port (vm, UDP_DST_PORT_bfd_echo4, -- cgit 1.2.3-korg