diff options
Diffstat (limited to 'src/vnet/ip/ip_path_mtu_node.c')
| -rw-r--r-- | src/vnet/ip/ip_path_mtu_node.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/src/vnet/ip/ip_path_mtu_node.c b/src/vnet/ip/ip_path_mtu_node.c new file mode 100644 index 00000000000..b13f9de849c --- /dev/null +++ b/src/vnet/ip/ip_path_mtu_node.c @@ -0,0 +1,206 @@ +/* + *------------------------------------------------------------------ + * ip_path_mtu.c + * + * Copyright (c) 2020 Graphiant. + * 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 <vnet/ip/ip_path_mtu.h> +#include <vnet/ip/ip_frag.h> + +typedef enum +{ + IP_PMTU_DROP, + IP_PMTU_N_NEXT, +} ip_pmtu_next_t; + +typedef struct ip_pmtu_trace_t_ +{ + u16 pmtu; + u16 packet_size; +} ip_pmtu_trace_t; + +static u8 * +format_ip_pmtu_trace (u8 *s, va_list *args) +{ + CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); + CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); + ip_pmtu_trace_t *t = va_arg (*args, ip_pmtu_trace_t *); + + s = format (s, "path mtu:%d packet size:%d", t->pmtu, t->packet_size); + + return s; +} + +static inline uword +ip_pmtu_dpo_inline (vlib_main_t *vm, vlib_node_runtime_t *node, + vlib_frame_t *frame, ip_address_family_t af) +{ + u32 n_left_from, *from, next_index, *to_next, n_left_to_next; + u32 frag_sent = 0, small_packets = 0; + + from = vlib_frame_vector_args (frame); + n_left_from = frame->n_vectors; + next_index = node->cached_next_index; + + u32 *buffer = 0; + + while (n_left_from > 0) + { + vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + + while (n_left_from > 0 && n_left_to_next > 0) + { + const ip_pmtu_dpo_t *ipm0; + u32 pi0, *frag_from, frag_left; + vlib_buffer_t *p0; + ip_frag_error_t error0; + u16 next0; + + /* + * Note: The packet is not enqueued now. It is instead put + * in a vector where other fragments will be put as well. + */ + pi0 = from[0]; + from += 1; + n_left_from -= 1; + + p0 = vlib_get_buffer (vm, pi0); + ipm0 = ip_pmtu_dpo_get (vnet_buffer (p0)->ip.adj_index[VLIB_TX]); + vnet_buffer (p0)->ip.adj_index[VLIB_TX] = ipm0->ipm_dpo.dpoi_index; + next0 = ipm0->ipm_dpo.dpoi_next_node; + + if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED)) + { + ip_pmtu_trace_t *t; + t = vlib_add_trace (vm, node, p0, sizeof (*t)); + t->pmtu = ipm0->ipm_pmtu; + t->packet_size = vlib_buffer_length_in_chain (vm, p0); + } + + if (AF_IP6 == af) + error0 = + ip6_frag_do_fragment (vm, pi0, ipm0->ipm_pmtu, 0, &buffer); + else + error0 = + ip4_frag_do_fragment (vm, pi0, ipm0->ipm_pmtu, 0, &buffer); + + if (AF_IP4 == af && error0 == IP_FRAG_ERROR_DONT_FRAGMENT_SET) + { + icmp4_error_set_vnet_buffer ( + p0, ICMP4_destination_unreachable, + ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set, + ipm0->ipm_pmtu); + next0 = IP_FRAG_NEXT_ICMP_ERROR; + } + else + { + next0 = + (error0 == IP_FRAG_ERROR_NONE ? next0 : IP_FRAG_NEXT_DROP); + } + + if (error0 == IP_FRAG_ERROR_NONE) + { + /* Free original buffer chain */ + frag_sent += vec_len (buffer); + small_packets += (vec_len (buffer) == 1); + vlib_buffer_free_one (vm, pi0); /* Free original packet */ + } + else + { + vlib_error_count (vm, node->node_index, error0, 1); + vec_add1 (buffer, pi0); /* Get rid of the original buffer */ + } + + /* Send fragments that were added in the frame */ + frag_from = buffer; + frag_left = vec_len (buffer); + + while (frag_left > 0) + { + while (frag_left > 0 && n_left_to_next > 0) + { + u32 i; + i = to_next[0] = frag_from[0]; + frag_from += 1; + frag_left -= 1; + to_next += 1; + n_left_to_next -= 1; + + vlib_get_buffer (vm, i)->error = node->errors[error0]; + vlib_validate_buffer_enqueue_x1 ( + vm, node, next_index, to_next, n_left_to_next, i, next0); + } + vlib_put_next_frame (vm, node, next_index, n_left_to_next); + vlib_get_next_frame (vm, node, next_index, to_next, + n_left_to_next); + } + vec_reset_length (buffer); + } + vlib_put_next_frame (vm, node, next_index, n_left_to_next); + } + vec_free (buffer); + + return frame->n_vectors; +} + +// clang-format off + +VLIB_NODE_FN (ip4_ip_pmtu_dpo_node) (vlib_main_t *vm, + vlib_node_runtime_t *node, + vlib_frame_t *from_frame) +{ + return (ip_pmtu_dpo_inline (vm, node, from_frame, 0)); +} + +VLIB_NODE_FN (ip6_ip_pmtu_dpo_node) (vlib_main_t *vm, + vlib_node_runtime_t *node, + vlib_frame_t *from_frame) +{ + return (ip_pmtu_dpo_inline (vm, node, from_frame, 1)); +} + +VLIB_REGISTER_NODE (ip4_ip_pmtu_dpo_node) = { + .name = "ip4-pmtu-dpo", + .vector_size = sizeof (u32), + .format_trace = format_ip_pmtu_trace, + .n_errors = 0, + .n_next_nodes = IP_PMTU_N_NEXT, + .next_nodes = + { + [IP_PMTU_DROP] = "ip4-drop", + } +}; +VLIB_REGISTER_NODE (ip6_ip_pmtu_dpo_node) = { + .name = "ip6-pmtu-dpo", + .vector_size = sizeof (u32), + .format_trace = format_ip_pmtu_trace, + .n_errors = 0, + .n_next_nodes = IP_PMTU_N_NEXT, + .next_nodes = + { + [IP_PMTU_DROP] = "ip6-drop", + } +}; + +// clang-format on + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |