X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fplugins%2Fsnat%2Fout2in.c;h=3c1bb8852f67db3d6fd6a76035abf058dce8ca7f;hb=b33f413af46ec8dff7f222dbd5bc3bcec1502d3d;hp=4f3322a3231a442da13ac2154ca99039108a1086;hpb=205e934ee7530dac475be14d9054183625171ccc;p=vpp.git diff --git a/src/plugins/snat/out2in.c b/src/plugins/snat/out2in.c index 4f3322a3231..3c1bb8852f6 100644 --- a/src/plugins/snat/out2in.c +++ b/src/plugins/snat/out2in.c @@ -103,6 +103,7 @@ static char * snat_out2in_error_strings[] = { typedef enum { SNAT_OUT2IN_NEXT_DROP, SNAT_OUT2IN_NEXT_LOOKUP, + SNAT_OUT2IN_NEXT_ICMP_ERROR, SNAT_OUT2IN_N_NEXT, } snat_out2in_next_t; @@ -222,6 +223,10 @@ create_session_for_static_mapping (snat_main_t *sm, return s; } +typedef struct { + u16 src_port, dst_port; +} tcp_udp_header_t; + static inline u32 icmp_out2in_slow_path (snat_main_t *sm, vlib_buffer_t * b0, ip4_header_t * ip0, @@ -230,24 +235,73 @@ static inline u32 icmp_out2in_slow_path (snat_main_t *sm, u32 rx_fib_index0, vlib_node_runtime_t * node, u32 next0, f64 now, - u32 cpu_index) + u32 cpu_index, + snat_session_t ** p_s0) { snat_session_key_t key0, sm0; - icmp_echo_header_t *echo0; + icmp_echo_header_t *echo0, *inner_echo0 = 0; + ip4_header_t *inner_ip0 = 0; + void *l4_header = 0; + icmp46_header_t *inner_icmp0; clib_bihash_kv_8_8_t kv0, value0; - snat_session_t * s0; + snat_session_t * s0 = 0; u32 new_addr0, old_addr0; u16 old_id0, new_id0; ip_csum_t sum0; + u16 checksum0; snat_runtime_t * rt = (snat_runtime_t *)node->runtime_data; + u8 is_error_message = 0; echo0 = (icmp_echo_header_t *)(icmp0+1); key0.addr = ip0->dst_address; - key0.port = echo0->identifier; - key0.protocol = SNAT_PROTOCOL_ICMP; key0.fib_index = rx_fib_index0; - + + switch(icmp0->type) + { + case ICMP4_destination_unreachable: + case ICMP4_time_exceeded: + case ICMP4_parameter_problem: + case ICMP4_source_quench: + case ICMP4_redirect: + case ICMP4_alternate_host_address: + is_error_message = 1; + } + + if (!is_error_message) + { + if (PREDICT_FALSE(icmp0->type != ICMP4_echo_reply)) + { + b0->error = node->errors[SNAT_OUT2IN_ERROR_BAD_ICMP_TYPE]; + next0 = SNAT_OUT2IN_NEXT_DROP; + goto out; + } + key0.protocol = SNAT_PROTOCOL_ICMP; + key0.port = echo0->identifier; + } + else + { + inner_ip0 = (ip4_header_t *)(echo0+1); + l4_header = ip4_next_header (inner_ip0); + key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol); + switch (key0.protocol) + { + case SNAT_PROTOCOL_ICMP: + inner_icmp0 = (icmp46_header_t*)l4_header; + inner_echo0 = (icmp_echo_header_t *)(inner_icmp0+1); + key0.port = inner_echo0->identifier; + break; + case SNAT_PROTOCOL_UDP: + case SNAT_PROTOCOL_TCP: + key0.port = ((tcp_udp_header_t*)l4_header)->src_port; + break; + default: + b0->error = node->errors[SNAT_OUT2IN_ERROR_UNSUPPORTED_PROTOCOL]; + next0 = SNAT_OUT2IN_NEXT_DROP; + goto out; + } + } + kv0.key = key0.as_u64; if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0)) @@ -271,43 +325,108 @@ static inline u32 icmp_out2in_slow_path (snat_main_t *sm, } /* Don't NAT packet aimed at the intfc address */ - if (PREDICT_FALSE(ip0->dst_address.as_u32 == - rt->cached_ip4_address)) - return next0; + if (PREDICT_FALSE(ip0->dst_address.as_u32 == rt->cached_ip4_address)) + goto out; b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; - return SNAT_OUT2IN_NEXT_DROP; + next0 = SNAT_OUT2IN_NEXT_DROP; + goto out; + } + + if (is_error_message) + { + next0 = SNAT_OUT2IN_NEXT_DROP; + goto out; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node, cpu_index); + if (!s0) - return SNAT_OUT2IN_NEXT_DROP; + { + next0 = SNAT_OUT2IN_NEXT_DROP; + goto out; + } } else s0 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions, value0.value); + sum0 = ip_incremental_checksum (0, icmp0, + ntohs(ip0->length) - ip4_header_bytes (ip0)); + checksum0 = ~ip_csum_fold (sum0); + if (checksum0 != 0 && checksum0 != 0xffff) + { + next0 = SNAT_OUT2IN_NEXT_DROP; + goto out; + } + old_addr0 = ip0->dst_address.as_u32; ip0->dst_address = s0->in2out.addr; new_addr0 = ip0->dst_address.as_u32; vnet_buffer(b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index; sum0 = ip0->checksum; - sum0 = ip_csum_update (sum0, old_addr0, new_addr0, - ip4_header_t, + sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); ip0->checksum = ip_csum_fold (sum0); - old_id0 = echo0->identifier; - new_id0 = s0->in2out.port; - echo0->identifier = new_id0; + if (!is_error_message) + { + old_id0 = echo0->identifier; + new_id0 = s0->in2out.port; + echo0->identifier = new_id0; + + sum0 = icmp0->checksum; + sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t, + identifier /* changed member */); + icmp0->checksum = ip_csum_fold (sum0); + } + else + { + if (!ip4_header_checksum_is_valid (inner_ip0)) + { + next0 = SNAT_OUT2IN_NEXT_DROP; + goto out; + } + + old_addr0 = inner_ip0->src_address.as_u32; + inner_ip0->src_address = s0->in2out.addr; + new_addr0 = inner_ip0->src_address.as_u32; + + sum0 = icmp0->checksum; + sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, + src_address /* changed member */); + icmp0->checksum = ip_csum_fold (sum0); - sum0 = icmp0->checksum; - sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t, - identifier); - icmp0->checksum = ip_csum_fold (sum0); + switch (key0.protocol) + { + case SNAT_PROTOCOL_ICMP: + old_id0 = inner_echo0->identifier; + new_id0 = s0->in2out.port; + inner_echo0->identifier = new_id0; + + sum0 = icmp0->checksum; + sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t, + identifier); + icmp0->checksum = ip_csum_fold (sum0); + break; + case SNAT_PROTOCOL_UDP: + case SNAT_PROTOCOL_TCP: + old_id0 = ((tcp_udp_header_t*)l4_header)->src_port; + new_id0 = s0->in2out.port; + ((tcp_udp_header_t*)l4_header)->src_port = new_id0; + + sum0 = icmp0->checksum; + sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t, + src_port); + icmp0->checksum = ip_csum_fold (sum0); + break; + default: + ASSERT(0); + } + } /* Accounting */ s0->last_heard = now; @@ -323,6 +442,8 @@ static inline u32 icmp_out2in_slow_path (snat_main_t *sm, s0->per_user_index); } +out: + *p_s0 = s0; return next0; } @@ -410,11 +531,21 @@ snat_out2in_node_fn (vlib_main_t * vm, if (PREDICT_FALSE (proto0 == ~0)) goto trace0; + if (PREDICT_FALSE(ip0->ttl == 1)) + { + vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded, + ICMP4_time_exceeded_ttl_exceeded_in_transit, + 0); + next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR; + goto trace0; + } + if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP)) { next0 = icmp_out2in_slow_path (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, - next0, now, cpu_index); + next0, now, cpu_index, &s0); goto trace0; } @@ -535,11 +666,21 @@ snat_out2in_node_fn (vlib_main_t * vm, if (PREDICT_FALSE (proto1 == ~0)) goto trace1; + if (PREDICT_FALSE(ip0->ttl == 1)) + { + vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0; + icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded, + ICMP4_time_exceeded_ttl_exceeded_in_transit, + 0); + next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR; + goto trace1; + } + if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP)) { next1 = icmp_out2in_slow_path (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node, - next1, now, cpu_index); + next1, now, cpu_index, &s1); goto trace1; } @@ -694,11 +835,21 @@ snat_out2in_node_fn (vlib_main_t * vm, if (PREDICT_FALSE (proto0 == ~0)) goto trace00; + if (PREDICT_FALSE(ip0->ttl == 1)) + { + vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded, + ICMP4_time_exceeded_ttl_exceeded_in_transit, + 0); + next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR; + goto trace00; + } + if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP)) { next0 = icmp_out2in_slow_path (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, - next0, now, cpu_index); + next0, now, cpu_index, &s0); goto trace00; } @@ -838,6 +989,7 @@ VLIB_REGISTER_NODE (snat_out2in_node) = { .next_nodes = { [SNAT_OUT2IN_NEXT_DROP] = "error-drop", [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup", + [SNAT_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error", }, }; VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_node, snat_out2in_node_fn); @@ -1295,6 +1447,7 @@ VLIB_REGISTER_NODE (snat_out2in_fast_node) = { .next_nodes = { [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup", [SNAT_OUT2IN_NEXT_DROP] = "error-drop", + [SNAT_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error", }, }; VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_fast_node, snat_out2in_fast_node_fn);