diff options
Diffstat (limited to 'src/plugins/nat/nat64_out2in.c')
| -rw-r--r-- | src/plugins/nat/nat64_out2in.c | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/src/plugins/nat/nat64_out2in.c b/src/plugins/nat/nat64_out2in.c new file mode 100644 index 00000000..61e88a7f --- /dev/null +++ b/src/plugins/nat/nat64_out2in.c @@ -0,0 +1,494 @@ +/* + * Copyright (c) 2017 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. + */ +/** + * @file + * @brief NAT64 IPv4 to IPv6 translation (otside to inside network) + */ + +#include <nat/nat64.h> +#include <vnet/ip/ip4_to_ip6.h> +#include <vnet/fib/ip4_fib.h> + +typedef struct +{ + u32 sw_if_index; + u32 next_index; +} nat64_out2in_trace_t; + +static u8 * +format_nat64_out2in_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 *); + nat64_out2in_trace_t *t = va_arg (*args, nat64_out2in_trace_t *); + + s = + format (s, "NAT64-out2in: sw_if_index %d, next index %d", t->sw_if_index, + t->next_index); + + return s; +} + +vlib_node_registration_t nat64_out2in_node; + +#define foreach_nat64_out2in_error \ +_(UNSUPPORTED_PROTOCOL, "Unsupported protocol") \ +_(OUT2IN_PACKETS, "Good out2in packets processed") \ +_(NO_TRANSLATION, "No translation") \ +_(UNKNOWN, "unknown") + +typedef enum +{ +#define _(sym,str) NAT64_OUT2IN_ERROR_##sym, + foreach_nat64_out2in_error +#undef _ + NAT64_OUT2IN_N_ERROR, +} nat64_out2in_error_t; + +static char *nat64_out2in_error_strings[] = { +#define _(sym,string) string, + foreach_nat64_out2in_error +#undef _ +}; + +typedef enum +{ + NAT64_OUT2IN_NEXT_LOOKUP, + NAT64_OUT2IN_NEXT_DROP, + NAT64_OUT2IN_N_NEXT, +} nat64_out2in_next_t; + +typedef struct nat64_out2in_set_ctx_t_ +{ + vlib_buffer_t *b; + vlib_main_t *vm; +} nat64_out2in_set_ctx_t; + +static int +nat64_out2in_tcp_udp_set_cb (ip4_header_t * ip4, ip6_header_t * ip6, + void *arg) +{ + nat64_main_t *nm = &nat64_main; + nat64_out2in_set_ctx_t *ctx = arg; + nat64_db_bib_entry_t *bibe; + nat64_db_st_entry_t *ste; + ip46_address_t saddr, daddr; + ip6_address_t ip6_saddr; + udp_header_t *udp = ip4_next_header (ip4); + tcp_header_t *tcp = ip4_next_header (ip4); + u8 proto = ip4->protocol; + u16 dport = udp->dst_port; + u16 sport = udp->src_port; + u32 sw_if_index, fib_index; + u16 *checksum; + ip_csum_t csum; + + sw_if_index = vnet_buffer (ctx->b)->sw_if_index[VLIB_RX]; + fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index); + + memset (&saddr, 0, sizeof (saddr)); + saddr.ip4.as_u32 = ip4->src_address.as_u32; + memset (&daddr, 0, sizeof (daddr)); + daddr.ip4.as_u32 = ip4->dst_address.as_u32; + + ste = + nat64_db_st_entry_find (&nm->db, &daddr, &saddr, dport, sport, proto, + fib_index, 0); + if (ste) + { + bibe = nat64_db_bib_entry_by_index (&nm->db, proto, ste->bibe_index); + if (!bibe) + return -1; + } + else + { + bibe = + nat64_db_bib_entry_find (&nm->db, &daddr, dport, proto, fib_index, 0); + + if (!bibe) + return -1; + + nat64_compose_ip6 (&ip6_saddr, &ip4->src_address, bibe->fib_index); + ste = + nat64_db_st_entry_create (&nm->db, bibe, &ip6_saddr, &saddr.ip4, + sport); + } + + nat64_session_reset_timeout (ste, ctx->vm); + + ip6->src_address.as_u64[0] = ste->in_r_addr.as_u64[0]; + ip6->src_address.as_u64[1] = ste->in_r_addr.as_u64[1]; + + ip6->dst_address.as_u64[0] = bibe->in_addr.as_u64[0]; + ip6->dst_address.as_u64[1] = bibe->in_addr.as_u64[1]; + udp->dst_port = bibe->in_port; + + if (proto == IP_PROTOCOL_UDP) + checksum = &udp->checksum; + else + checksum = &tcp->checksum; + csum = ip_csum_sub_even (*checksum, dport); + csum = ip_csum_add_even (csum, udp->dst_port); + *checksum = ip_csum_fold (csum); + + vnet_buffer (ctx->b)->sw_if_index[VLIB_TX] = bibe->fib_index; + + return 0; +} + +static int +nat64_out2in_icmp_set_cb (ip4_header_t * ip4, ip6_header_t * ip6, void *arg) +{ + nat64_main_t *nm = &nat64_main; + nat64_out2in_set_ctx_t *ctx = arg; + nat64_db_bib_entry_t *bibe; + nat64_db_st_entry_t *ste; + ip46_address_t saddr, daddr; + ip6_address_t ip6_saddr; + u32 sw_if_index, fib_index; + icmp46_header_t *icmp = ip4_next_header (ip4); + + sw_if_index = vnet_buffer (ctx->b)->sw_if_index[VLIB_RX]; + fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index); + + memset (&saddr, 0, sizeof (saddr)); + saddr.ip4.as_u32 = ip4->src_address.as_u32; + memset (&daddr, 0, sizeof (daddr)); + daddr.ip4.as_u32 = ip4->dst_address.as_u32; + + if (icmp->type == ICMP6_echo_request || icmp->type == ICMP6_echo_reply) + { + u16 out_id = ((u16 *) (icmp))[2]; + ste = + nat64_db_st_entry_find (&nm->db, &daddr, &saddr, out_id, 0, + IP_PROTOCOL_ICMP, fib_index, 0); + + if (ste) + { + bibe = + nat64_db_bib_entry_by_index (&nm->db, IP_PROTOCOL_ICMP, + ste->bibe_index); + if (!bibe) + return -1; + } + else + { + bibe = + nat64_db_bib_entry_find (&nm->db, &daddr, out_id, + IP_PROTOCOL_ICMP, fib_index, 0); + if (!bibe) + return -1; + + nat64_compose_ip6 (&ip6_saddr, &ip4->src_address, bibe->fib_index); + ste = + nat64_db_st_entry_create (&nm->db, bibe, &ip6_saddr, &saddr.ip4, + 0); + } + + nat64_session_reset_timeout (ste, ctx->vm); + + ip6->src_address.as_u64[0] = ste->in_r_addr.as_u64[0]; + ip6->src_address.as_u64[1] = ste->in_r_addr.as_u64[1]; + + ip6->dst_address.as_u64[0] = bibe->in_addr.as_u64[0]; + ip6->dst_address.as_u64[1] = bibe->in_addr.as_u64[1]; + ((u16 *) (icmp))[2] = bibe->in_port; + + vnet_buffer (ctx->b)->sw_if_index[VLIB_TX] = bibe->fib_index; + } + else + { + ip6_header_t *inner_ip6 = (ip6_header_t *) u8_ptr_add (icmp, 8); + + nat64_compose_ip6 (&ip6->src_address, &ip4->src_address, + vnet_buffer (ctx->b)->sw_if_index[VLIB_TX]); + ip6->dst_address.as_u64[0] = inner_ip6->src_address.as_u64[0]; + ip6->dst_address.as_u64[1] = inner_ip6->src_address.as_u64[1]; + } + + return 0; +} + +static int +nat64_out2in_inner_icmp_set_cb (ip4_header_t * ip4, ip6_header_t * ip6, + void *arg) +{ + nat64_main_t *nm = &nat64_main; + nat64_out2in_set_ctx_t *ctx = arg; + nat64_db_bib_entry_t *bibe; + nat64_db_st_entry_t *ste; + ip46_address_t saddr, daddr; + u32 sw_if_index, fib_index; + u8 proto = ip4->protocol; + + sw_if_index = vnet_buffer (ctx->b)->sw_if_index[VLIB_RX]; + fib_index = + fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP6, sw_if_index); + + memset (&saddr, 0, sizeof (saddr)); + saddr.ip4.as_u32 = ip4->src_address.as_u32; + memset (&daddr, 0, sizeof (daddr)); + daddr.ip4.as_u32 = ip4->dst_address.as_u32; + + if (proto == IP_PROTOCOL_ICMP6) + { + icmp46_header_t *icmp = ip4_next_header (ip4); + u16 out_id = ((u16 *) (icmp))[2]; + proto = IP_PROTOCOL_ICMP; + + if (! + (icmp->type == ICMP6_echo_request + || icmp->type == ICMP6_echo_reply)) + return -1; + + ste = + nat64_db_st_entry_find (&nm->db, &saddr, &daddr, out_id, 0, proto, + fib_index, 0); + if (!ste) + return -1; + + bibe = nat64_db_bib_entry_by_index (&nm->db, proto, ste->bibe_index); + if (!bibe) + return -1; + + ip6->dst_address.as_u64[0] = ste->in_r_addr.as_u64[0]; + ip6->dst_address.as_u64[1] = ste->in_r_addr.as_u64[1]; + ip6->src_address.as_u64[0] = bibe->in_addr.as_u64[0]; + ip6->src_address.as_u64[1] = bibe->in_addr.as_u64[1]; + ((u16 *) (icmp))[2] = bibe->in_port; + + vnet_buffer (ctx->b)->sw_if_index[VLIB_TX] = bibe->fib_index; + } + else + { + udp_header_t *udp = ip4_next_header (ip4); + tcp_header_t *tcp = ip4_next_header (ip4); + u16 dport = udp->dst_port; + u16 sport = udp->src_port; + u16 *checksum; + ip_csum_t csum; + + ste = + nat64_db_st_entry_find (&nm->db, &saddr, &daddr, sport, dport, proto, + fib_index, 0); + if (!ste) + return -1; + + bibe = nat64_db_bib_entry_by_index (&nm->db, proto, ste->bibe_index); + if (!bibe) + return -1; + + nat64_compose_ip6 (&ip6->dst_address, &daddr.ip4, bibe->fib_index); + ip6->src_address.as_u64[0] = bibe->in_addr.as_u64[0]; + ip6->src_address.as_u64[1] = bibe->in_addr.as_u64[1]; + udp->src_port = bibe->in_port; + + if (proto == IP_PROTOCOL_UDP) + checksum = &udp->checksum; + else + checksum = &tcp->checksum; + if (*checksum) + { + csum = ip_csum_sub_even (*checksum, sport); + csum = ip_csum_add_even (csum, udp->src_port); + *checksum = ip_csum_fold (csum); + } + + vnet_buffer (ctx->b)->sw_if_index[VLIB_TX] = bibe->fib_index; + } + + return 0; +} + +static int +nat64_out2in_unk_proto_set_cb (ip4_header_t * ip4, ip6_header_t * ip6, + void *arg) +{ + nat64_main_t *nm = &nat64_main; + nat64_out2in_set_ctx_t *ctx = arg; + nat64_db_bib_entry_t *bibe; + nat64_db_st_entry_t *ste; + ip46_address_t saddr, daddr; + ip6_address_t ip6_saddr; + u32 sw_if_index, fib_index; + u8 proto = ip4->protocol; + + sw_if_index = vnet_buffer (ctx->b)->sw_if_index[VLIB_RX]; + fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index); + + memset (&saddr, 0, sizeof (saddr)); + saddr.ip4.as_u32 = ip4->src_address.as_u32; + memset (&daddr, 0, sizeof (daddr)); + daddr.ip4.as_u32 = ip4->dst_address.as_u32; + + ste = + nat64_db_st_entry_find (&nm->db, &daddr, &saddr, 0, 0, proto, fib_index, + 0); + if (ste) + { + bibe = nat64_db_bib_entry_by_index (&nm->db, proto, ste->bibe_index); + if (!bibe) + return -1; + } + else + { + bibe = + nat64_db_bib_entry_find (&nm->db, &daddr, 0, proto, fib_index, 0); + + if (!bibe) + return -1; + + nat64_compose_ip6 (&ip6_saddr, &ip4->src_address, bibe->fib_index); + ste = + nat64_db_st_entry_create (&nm->db, bibe, &ip6_saddr, &saddr.ip4, 0); + } + + nat64_session_reset_timeout (ste, ctx->vm); + + ip6->src_address.as_u64[0] = ste->in_r_addr.as_u64[0]; + ip6->src_address.as_u64[1] = ste->in_r_addr.as_u64[1]; + + ip6->dst_address.as_u64[0] = bibe->in_addr.as_u64[0]; + ip6->dst_address.as_u64[1] = bibe->in_addr.as_u64[1]; + + vnet_buffer (ctx->b)->sw_if_index[VLIB_TX] = bibe->fib_index; + + return 0; +} + +static uword +nat64_out2in_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + u32 n_left_from, *from, *to_next; + nat64_out2in_next_t next_index; + u32 pkts_processed = 0; + + from = vlib_frame_vector_args (frame); + n_left_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; + vlib_buffer_t *b0; + u32 next0; + ip4_header_t *ip40; + u32 proto0; + nat64_out2in_set_ctx_t ctx0; + + /* speculatively enqueue b0 to the current next frame */ + bi0 = from[0]; + to_next[0] = bi0; + from += 1; + to_next += 1; + n_left_from -= 1; + n_left_to_next -= 1; + + b0 = vlib_get_buffer (vm, bi0); + ip40 = vlib_buffer_get_current (b0); + + ctx0.b = b0; + ctx0.vm = vm; + + next0 = NAT64_OUT2IN_NEXT_LOOKUP; + + proto0 = ip_proto_to_snat_proto (ip40->protocol); + + if (proto0 == SNAT_PROTOCOL_ICMP) + { + if (icmp_to_icmp6 + (b0, nat64_out2in_icmp_set_cb, &ctx0, + nat64_out2in_inner_icmp_set_cb, &ctx0)) + { + next0 = NAT64_OUT2IN_NEXT_DROP; + b0->error = node->errors[NAT64_OUT2IN_ERROR_NO_TRANSLATION]; + goto trace0; + } + } + else if (proto0 == SNAT_PROTOCOL_TCP || proto0 == SNAT_PROTOCOL_UDP) + { + if (ip4_to_ip6_tcp_udp (b0, nat64_out2in_tcp_udp_set_cb, &ctx0)) + { + next0 = NAT64_OUT2IN_NEXT_DROP; + b0->error = node->errors[NAT64_OUT2IN_ERROR_NO_TRANSLATION]; + goto trace0; + } + } + else + { + if (ip4_to_ip6 (b0, nat64_out2in_unk_proto_set_cb, &ctx0)) + { + next0 = NAT64_OUT2IN_NEXT_DROP; + b0->error = node->errors[NAT64_OUT2IN_ERROR_NO_TRANSLATION]; + goto trace0; + } + } + + trace0: + if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) + && (b0->flags & VLIB_BUFFER_IS_TRACED))) + { + nat64_out2in_trace_t *t = + vlib_add_trace (vm, node, b0, sizeof (*t)); + t->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX]; + t->next_index = next0; + } + + pkts_processed += next0 != NAT64_OUT2IN_NEXT_DROP; + + /* verify speculative enqueue, maybe switch current next frame */ + 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, nat64_out2in_node.index, + NAT64_OUT2IN_ERROR_OUT2IN_PACKETS, + pkts_processed); + return frame->n_vectors; +} + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (nat64_out2in_node) = { + .function = nat64_out2in_node_fn, + .name = "nat64-out2in", + .vector_size = sizeof (u32), + .format_trace = format_nat64_out2in_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + .n_errors = ARRAY_LEN (nat64_out2in_error_strings), + .error_strings = nat64_out2in_error_strings,.n_next_nodes = 2, + /* edit / add dispositions here */ + .next_nodes = { + [NAT64_OUT2IN_NEXT_DROP] = "error-drop", + [NAT64_OUT2IN_NEXT_LOOKUP] = "ip6-lookup", + }, +}; +/* *INDENT-ON* */ + +VLIB_NODE_FUNCTION_MULTIARCH (nat64_out2in_node, nat64_out2in_node_fn); + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |