/* * decap.c : IPSec tunnel decapsulation * * Copyright (c) 2015 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 <vnet/vnet.h> #include <vnet/api_errno.h> #include <vnet/ip/ip.h> #include <vnet/feature/feature.h> #include <vnet/ipsec/ipsec.h> #include <vnet/ipsec/esp.h> #define foreach_ipsec_input_error \ _(RX_PKTS, "IPSEC pkts received") \ _(DECRYPTION_FAILED, "IPSEC decryption failed") typedef enum { #define _(sym,str) IPSEC_INPUT_ERROR_##sym, foreach_ipsec_input_error #undef _ IPSEC_INPUT_N_ERROR, } ipsec_input_error_t; static char *ipsec_input_error_strings[] = { #define _(sym,string) string, foreach_ipsec_input_error #undef _ }; typedef struct { u32 sa_id; u32 spi; u32 seq; } ipsec_input_trace_t; /* packet trace format function */ static u8 * format_ipsec_input_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 *); ipsec_input_trace_t *t = va_arg (*args, ipsec_input_trace_t *); if (t->spi == 0 && t->seq == 0) { s = format (s, "esp: no esp packet"); return s; } if (t->sa_id != 0) { s = format (s, "esp: sa_id %u spi %u seq %u", t->sa_id, t->spi, t->seq); } else { s = format (s, "esp: no sa spi %u seq %u", t->spi, t->seq); } return s; } always_inline ipsec_policy_t * ipsec_input_protect_policy_match (ipsec_spd_t * spd, u32 sa, u32 da, u32 spi) { ipsec_main_t *im = &ipsec_main; ipsec_policy_t *p; ipsec_sa_t *s; u32 *i; vec_foreach (i, spd->ipv4_inbound_protect_policy_indices) { p = pool_elt_at_index (spd->policies, *i); s = pool_elt_at_index (im->sad, p->sa_index); if (spi != s->spi) continue; if (s->is_tunnel) { if (da != clib_net_to_host_u32 (s->tunnel_dst_addr.ip4.as_u32)) continue; if (sa != clib_net_to_host_u32 (s->tunnel_src_addr.ip4.as_u32)) continue; return p; } if (da < clib_net_to_host_u32 (p->laddr.start.ip4.as_u32)) continue; if (da > clib_net_to_host_u32 (p->laddr.stop.ip4.as_u32)) continue; if (sa < clib_net_to_host_u32 (p->raddr.start.ip4.as_u32)) continue; if (sa > clib_net_to_host_u32 (p->raddr.stop.ip4.as_u32)) continue; return p; } return 0; } always_inline uword ip6_addr_match_range (ip6_address_t * a, ip6_address_t * la, ip6_address_t * ua) { if ((memcmp (a->as_u64, la->as_u64, 2 * sizeof (u64)) >= 0) && (memcmp (a->as_u64, ua->as_u64, 2 * sizeof (u64)) <= 0)) return 1; return 0; } always_inline ipsec_policy_t * ipsec_input_ip6_protect_policy_match (ipsec_spd_t * spd, ip6_address_t * sa, ip6_address_t * da, u32 spi) { ipsec_main_t *im = &ipsec_main; ipsec_policy_t *p; ipsec_sa_t *s; u32 *i; vec_foreach (i, spd->ipv6_inbound_protect_policy_indices) { p = pool_elt_at_index (spd->policies, *i); s = pool_elt_at_index (im->sad, p->sa_index); if (spi != s->spi) continue; if (s->is_tunnel) { if (!ip6_address_is_equal (sa, &s->tunnel_src_addr.ip6)) continue; if (!ip6_address_is_equal (da, &s->tunnel_dst_addr.ip6)) continue; return p; } if (!ip6_addr_match_range (sa, &p->raddr.start.ip6, &p->raddr.stop.ip6)) continue; if (!ip6_addr_match_range (da, &p->laddr.start.ip6, &p->laddr.stop.ip6)) continue; return p; } return 0; } static vlib_node_registration_t ipsec_input_ip4_node; static uword ipsec_input_ip4_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame) { u32 n_left_from, *from, next_index, *to_next; ipsec_main_t *im = &ipsec_main; from = vlib_frame_vector_args (from_frame); n_left_from = from_frame->n_vectors; next_index = node->cached_next_index; while (n_left_from > 0) { u32 n_left_to_next; vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_from > 0 && n_left_to_next > 0) { u32 bi0, next0; vlib_buffer_t *b0; ip4_header_t *ip0; esp_header_t *esp0; ip4_ipsec_config_t *c0; ipsec_spd_t *spd0; ipsec_policy_t *p0 = 0; bi0 = to_next[0] = from[0]; from += 1; n_left_from -= 1; to_next += 1; n_left_to_next -= 1; b0 = vlib_get_buffer (vm, bi0); c0 = vnet_feature_next_with_data (vnet_buffer (b0)->sw_if_index [VLIB_RX], &next0, b0, sizeof (c0[0])); spd0 = pool_elt_at_index (im->spds, c0->spd_index); ip0 = vlib_buffer_get_current (b0); esp0 = (esp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0)); if (PREDICT_TRUE (ip0->protocol == IP_PROTOCOL_IPSEC_ESP)) { #if 0 clib_warning ("packet received from %U to %U spi %u size %u spd_id %u", format_ip4_address, ip0->src_address.as_u8, format_ip4_address, ip0->dst_address.as_u8, clib_net_to_host_u32 (esp0->spi), clib_net_to_host_u16 (ip0->length), spd0->id); #endif p0 = ipsec_input_protect_policy_match (spd0, clib_net_to_host_u32 (ip0->src_address. as_u32), clib_net_to_host_u32 (ip0->dst_address. as_u32), clib_net_to_host_u32 (esp0->spi)); if (PREDICT_TRUE (p0 != 0)) { p0->counter.packets++; p0->counter.bytes += clib_net_to_host_u16 (ip0->length); vnet_buffer (b0)->ipsec.sad_index = p0->sa_index; vnet_buffer (b0)->ipsec.flags = 0; next0 = im->esp_decrypt_next_index; vlib_buffer_advance (b0, ip4_header_bytes (ip0)); goto trace0; } } /* FIXME bypass and discard */ trace0: if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) { ipsec_input_trace_t *tr = vlib_add_trace (vm, node, b0, sizeof (*tr)); if (ip0->protocol == IP_PROTOCOL_IPSEC_ESP) { if (p0) tr->sa_id = p0->sa_id; tr->spi = clib_host_to_net_u32 (esp0->spi); tr->seq = clib_host_to_net_u32 (esp0->seq); } } vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, bi0, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } vlib_node_increment_counter (vm, ipsec_input_ip4_node.index, IPSEC_INPUT_ERROR_RX_PKTS, from_frame->n_vectors); return from_frame->n_vectors; } /* *INDENT-OFF* */ VLIB_REGISTER_NODE (ipsec_input_ip4_node,static) = { .function = ipsec_input_ip4_node_fn, .name = "ipsec-input-ip4", .vector_size = sizeof (u32), .format_trace = format_ipsec_input_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(ipsec_input_error_strings), .error_strings = ipsec_input_error_strings, .n_next_nodes = IPSEC_INPUT_N_NEXT, .next_nodes = { #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n, foreach_ipsec_input_next #undef _ }, }; /* *INDENT-ON* */ VLIB_NODE_FUNCTION_MULTIARCH (ipsec_input_ip4_node, ipsec_input_ip4_node_fn) static vlib_node_registration_t ipsec_input_ip6_node; static uword ipsec_input_ip6_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame) { u32 n_left_from, *from, next_index, *to_next; ipsec_main_t *im = &ipsec_main; from = vlib_frame_vector_args (from_frame); n_left_from = from_frame->n_vectors; next_index = node->cached_next_index; while (n_left_from > 0) { u32 n_left_to_next; vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_from > 0 && n_left_to_next > 0) { u32 bi0, next0; vlib_buffer_t *b0; ip6_header_t *ip0; esp_header_t *esp0; ip4_ipsec_config_t *c0; ipsec_spd_t *spd0; ipsec_policy_t *p0 = 0; u32 header_size = sizeof (ip0[0]); bi0 = to_next[0] = from[0]; from += 1; n_left_from -= 1; to_next += 1; n_left_to_next -= 1; b0 = vlib_get_buffer (vm, bi0); c0 = vnet_feature_next_with_data (vnet_buffer (b0)->sw_if_index [VLIB_RX], &next0, b0, sizeof (c0[0])); spd0 = pool_elt_at_index (im->spds, c0->spd_index); ip0 = vlib_buffer_get_current (b0); esp0 = (esp_header_t *) ((u8 *) ip0 + header_size); if (PREDICT_TRUE (ip0->protocol == IP_PROTOCOL_IPSEC_ESP)) { #if 0 clib_warning ("packet received from %U to %U spi %u size %u spd_id %u", format_ip6_address, &ip0->src_address, format_ip6_address, &ip0->dst_address, clib_net_to_host_u32 (esp0->spi), clib_net_to_host_u16 (ip0->payload_length) + header_size, spd0->id); #endif p0 = ipsec_input_ip6_protect_policy_match (spd0, &ip0->src_address, &ip0->dst_address, clib_net_to_host_u32 (esp0->spi)); if (PREDICT_TRUE (p0 != 0)) { p0->counter.packets++; p0->counter.bytes += clib_net_to_host_u16 (ip0->payload_length); p0->counter.bytes += header_size; vnet_buffer (b0)->ipsec.sad_index = p0->sa_index; vnet_buffer (b0)->ipsec.flags = 0; next0 = im->esp_decrypt_next_index; vlib_buffer_advance (b0, header_size); goto trace0; } } trace0: if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) { ipsec_input_trace_t *tr = vlib_add_trace (vm, node, b0, sizeof (*tr)); if (ip0->protocol == IP_PROTOCOL_IPSEC_ESP) { if (p0) tr->sa_id = p0->sa_id; tr->spi = clib_host_to_net_u32 (esp0->spi); tr->seq = clib_host_to_net_u32 (esp0->seq); } } vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, bi0, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } vlib_node_increment_counter (vm, ipsec_input_ip6_node.index, IPSEC_INPUT_ERROR_RX_PKTS, from_frame->n_vectors); return from_frame->n_vectors; } /* *INDENT-OFF* */ VLIB_REGISTER_NODE (ipsec_input_ip6_node,static) = { .function = ipsec_input_ip6_node_fn, .name = "ipsec-input-ip6", .vector_size = sizeof (u32), .format_trace = format_ipsec_input_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(ipsec_input_error_strings), .error_strings = ipsec_input_error_strings, .sibling_of = "ipsec-input-ip4", }; /* *INDENT-ON* */ VLIB_NODE_FUNCTION_MULTIARCH (ipsec_input_ip6_node, ipsec_input_ip6_node_fn) /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */