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-rw-r--r--src/plugins/ipsecmb/ah_decrypt.c493
1 files changed, 493 insertions, 0 deletions
diff --git a/src/plugins/ipsecmb/ah_decrypt.c b/src/plugins/ipsecmb/ah_decrypt.c
new file mode 100644
index 00000000000..e991671aa63
--- /dev/null
+++ b/src/plugins/ipsecmb/ah_decrypt.c
@@ -0,0 +1,493 @@
+/*
+ * ah_decrypt.c : ipsecmb AH decrypt node
+ *
+ * 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/ipsec/ipsec.h>
+#include <vnet/ipsec/esp.h>
+#include <vnet/ipsec/ah.h>
+
+#include <ipsecmb/ipsecmb.h>
+
+#define foreach_ah_decrypt_next \
+ _ (DROP, "error-drop") \
+ _ (IP4_INPUT, "ip4-input") \
+ _ (IP6_INPUT, "ip6-input") \
+ _ (IPSEC_GRE_INPUT, "ipsec-gre-input")
+
+#define _(v, s) AH_DECRYPT_NEXT_##v,
+typedef enum
+{
+ foreach_ah_decrypt_next
+#undef _
+ AH_DECRYPT_N_NEXT,
+} ah_decrypt_next_t;
+
+#define foreach_ah_decrypt_error \
+ _ (RX_PKTS, "AH pkts received") \
+ _ (DECRYPTION_FAILED, "AH decryption failed") \
+ _ (INTEG_ERROR, "Integrity check failed") \
+ _ (REPLAY, "SA replayed packet") \
+ _ (NOT_IP, "Not IP packet (dropped)")
+
+typedef enum
+{
+#define _(sym, str) AH_DECRYPT_ERROR_##sym,
+ foreach_ah_decrypt_error
+#undef _
+ AH_DECRYPT_N_ERROR,
+} ah_decrypt_error_t;
+
+static char *ah_decrypt_error_strings[] = {
+#define _(sym, string) string,
+ foreach_ah_decrypt_error
+#undef _
+};
+
+typedef struct
+{
+ ipsec_integ_alg_t integ_alg;
+} ah_decrypt_trace_t;
+
+/* packet trace format function */
+static u8 *
+format_ah_decrypt_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 *);
+ ah_decrypt_trace_t *t = va_arg (*args, ah_decrypt_trace_t *);
+
+ s = format (s, "ah: integrity %U", format_ipsec_integ_alg, t->integ_alg);
+ return s;
+}
+
+typedef struct
+{
+ u8 tos;
+ u8 ttl;
+ u32 ip_version_traffic_class_and_flow_label;
+ u8 hop_limit;
+} ip_mutable_data_t;
+
+#ifdef CLIB_MARCH_VARIANT
+always_inline void
+remove_ah (vlib_main_t * vm, vlib_node_runtime_t * node, u32 * bi0,
+ u32 * next0, ipsec_sa_t * sa0, u32 ip_hdr_size, u32 icv_size,
+ u8 icv_padding_len, ah_header_t * ah0, int is_ip6)
+{
+ vlib_buffer_t *b0 = vlib_get_buffer (vm, *bi0);
+
+ if (sa0->is_tunnel)
+ { /* tunnel mode */
+ vlib_buffer_advance (b0, ip_hdr_size + sizeof (ah_header_t) + icv_size +
+ icv_padding_len);
+ if (ah0->nexthdr == IP_PROTOCOL_IP_IN_IP)
+ *next0 = AH_DECRYPT_NEXT_IP4_INPUT;
+ else if (ah0->nexthdr == IP_PROTOCOL_IPV6)
+ *next0 = AH_DECRYPT_NEXT_IP6_INPUT;
+ else
+ {
+ clib_warning ("next header: 0x%x", ah0->nexthdr);
+ vlib_node_increment_counter (vm, node->node_index,
+ AH_DECRYPT_ERROR_DECRYPTION_FAILED, 1);
+ *next0 = AH_DECRYPT_NEXT_DROP;
+ return;
+ }
+ }
+ else
+ { /* transport mode */
+ const size_t ip_hdr_offset =
+ sizeof (ah_header_t) + icv_size + icv_padding_len;
+ if (is_ip6)
+ { /* ipv6 */
+ ip6_header_t *ih6 =
+ (ip6_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
+ ip_hdr_offset);
+ u8 nexthdr = ah0->nexthdr;
+ memmove (ih6, vlib_buffer_get_current (b0), sizeof (ip6_header_t));
+ vlib_buffer_advance (b0, ip_hdr_offset);
+
+ *next0 = AH_DECRYPT_NEXT_IP6_INPUT;
+ ih6->protocol = nexthdr;
+ ih6->payload_length =
+ clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
+ sizeof (ip6_header_t));
+ }
+ else
+ { /* ipv4 */
+ ip4_header_t *ih4 =
+ (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
+ ip_hdr_offset);
+ u8 nexthdr = ah0->nexthdr;
+ memmove (ih4, vlib_buffer_get_current (b0), sizeof (ip4_header_t));
+ vlib_buffer_advance (b0, ip_hdr_offset);
+
+ *next0 = AH_DECRYPT_NEXT_IP4_INPUT;
+ ih4->ip_version_and_header_length = 0x45;
+ ih4->fragment_id = 0;
+ ih4->flags_and_fragment_offset = 0;
+ ih4->protocol = nexthdr;
+ ih4->length =
+ clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
+ ih4->checksum = ip4_header_checksum (ih4);
+ }
+ }
+
+ /* for IPSec-GRE tunnel next node is ipsec-gre-input */
+ if (PREDICT_FALSE
+ ((vnet_buffer (b0)->ipsec.flags & IPSEC_FLAG_IPSEC_GRE_TUNNEL)))
+ {
+ *next0 = AH_DECRYPT_NEXT_IPSEC_GRE_INPUT;
+ }
+}
+
+always_inline void
+ah_finish_decrypt (vlib_main_t * vm, vlib_node_runtime_t * node,
+ JOB_AES_HMAC * job, u32 * bi0, u32 * next0, int is_ip6)
+{
+ ipsec_main_t *im = &ipsec_main;
+ *bi0 = (uintptr_t) job->user_data;
+ vlib_buffer_t *b0 = vlib_get_buffer (vm, *bi0);
+ ipsec_sa_t *sa0 =
+ pool_elt_at_index (im->sad, vnet_buffer (b0)->ipsec.sad_index);
+ ipsec_proto_main_t *em = &ipsec_proto_main;
+ u32 icv_size = em->ipsec_proto_main_integ_algs[sa0->integ_alg].trunc_size;
+ u32 ip_hdr_size = 0;
+ ip4_header_t *ih4 = vlib_buffer_get_current (b0);
+ size_t seq_size = 0;
+ if (PREDICT_TRUE (sa0->use_esn))
+ {
+ seq_size = sizeof (u32);
+ }
+ ip_mutable_data_t *md =
+ (ip_mutable_data_t *) ((u8 *) vlib_buffer_get_current (b0) +
+ b0->current_length + seq_size + icv_size);
+ if (is_ip6)
+ {
+ ip_hdr_size = sizeof (ip6_header_t);
+ ip6_header_t *ih6 = vlib_buffer_get_current (b0);
+ ih6->ip_version_traffic_class_and_flow_label =
+ md->ip_version_traffic_class_and_flow_label;
+ ih6->hop_limit = md->hop_limit;
+ }
+ else
+ {
+ ip_hdr_size = ip4_header_bytes (ih4);
+ ih4->ttl = md->ttl;
+ ih4->tos = md->tos;
+ }
+
+ u8 icv_padding_len = ah_calc_icv_padding_len (icv_size, is_ip6);
+ ah_header_t *ah0 =
+ (ah_header_t *) ((u8 *) vlib_buffer_get_current (b0) + ip_hdr_size);
+ void *digest = ah0 + 1;
+ void *sig = vlib_buffer_get_current (b0) + b0->current_length + seq_size;
+
+ if (PREDICT_FALSE (memcmp (digest, sig, icv_size)))
+ {
+ vlib_node_increment_counter (vm, node->node_index,
+ AH_DECRYPT_ERROR_INTEG_ERROR, 1);
+ *next0 = AH_DECRYPT_NEXT_DROP;
+ return;
+ }
+
+ if (PREDICT_TRUE (sa0->use_anti_replay))
+ {
+ if (PREDICT_TRUE (sa0->use_esn))
+ esp_replay_advance_esn (sa0, clib_host_to_net_u32 (ah0->seq_no));
+ else
+ esp_replay_advance (sa0, clib_host_to_net_u32 (ah0->seq_no));
+ }
+ remove_ah (vm, node, bi0, next0, sa0, ip_hdr_size, icv_size,
+ icv_padding_len, ah0, is_ip6);
+ vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
+}
+
+always_inline uword
+ah_decrypt_ipsecmb_inline (vlib_main_t * vm,
+ vlib_node_runtime_t * node,
+ vlib_frame_t * from_frame, int is_ip6)
+{
+ u32 n_left_from, *from, next_index, *to_next;
+ ipsec_main_t *im = &ipsec_main;
+ ipsecmb_main_t *imbm = &ipsecmb_main;
+ ipsec_proto_main_t *em = &ipsec_proto_main;
+ from = vlib_frame_vector_args (from_frame);
+ n_left_from = from_frame->n_vectors;
+ int icv_size = 0;
+ u32 thread_index = vlib_get_thread_index ();
+ MB_MGR *mgr = imbm->mb_mgr[thread_index];
+ u32 packets_in_flight = 0;
+
+ next_index = node->cached_next_index;
+
+ while (n_left_from > 0 || packets_in_flight > 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;
+ u32 next0;
+ vlib_buffer_t *b0;
+ ah_header_t *ah0;
+ ipsec_sa_t *sa0;
+ ipsecmb_sa_t *samb0;
+ u32 sa_index0 = ~0;
+ u32 seq;
+ ip4_header_t *ih4 = 0;
+ ip6_header_t *ih6 = 0;
+ u8 ip_hdr_size = 0;
+
+ bi0 = from[0];
+ from += 1;
+ n_left_from -= 1;
+
+ next0 = AH_DECRYPT_NEXT_DROP;
+
+ b0 = vlib_get_buffer (vm, bi0);
+ ih4 = vlib_buffer_get_current (b0);
+ ih6 = vlib_buffer_get_current (b0);
+
+ sa_index0 = vnet_buffer (b0)->ipsec.sad_index;
+ sa0 = pool_elt_at_index (im->sad, sa_index0);
+ samb0 = pool_elt_at_index (imbm->sad, sa_index0);
+
+ if (is_ip6)
+ {
+ ip6_ext_header_t *prev = NULL;
+ ip6_ext_header_find_t (ih6, prev, ah0, IP_PROTOCOL_IPSEC_AH);
+ ip_hdr_size = sizeof (ip6_header_t);
+ ASSERT ((u8 *) ah0 - (u8 *) ih6 == ip_hdr_size);
+ }
+ else
+ {
+ ip_hdr_size = ip4_header_bytes (ih4);
+ ah0 = (ah_header_t *) (ih4 + 1);
+ }
+
+ seq = clib_host_to_net_u32 (ah0->seq_no);
+ /* anti-replay check */
+ // TODO UT remaining
+ if (sa0->use_anti_replay)
+ {
+ int rv = 0;
+
+ if (PREDICT_TRUE (sa0->use_esn))
+ rv = esp_replay_check_esn (sa0, seq);
+ else
+ rv = esp_replay_check (sa0, seq);
+
+ if (PREDICT_FALSE (rv))
+ {
+ clib_warning ("anti-replay SPI %u seq %u", sa0->spi, seq);
+ vlib_node_increment_counter (vm, node->node_index,
+ AH_DECRYPT_ERROR_REPLAY, 1);
+ goto trace;
+ }
+ }
+
+ sa0->total_data_size += b0->current_length;
+ icv_size =
+ em->ipsec_proto_main_integ_algs[sa0->integ_alg].trunc_size;
+ if (PREDICT_TRUE (sa0->integ_alg != IPSEC_INTEG_ALG_NONE))
+ {
+ u8 *icv = (u8 *) vlib_buffer_get_current (b0) + ip_hdr_size +
+ sizeof (ah_header_t);
+ size_t seq_size = 0;
+ if (PREDICT_TRUE (sa0->use_esn))
+ {
+ *(u32 *) (vlib_buffer_get_current (b0) +
+ b0->current_length) = sa0->seq_hi;
+ seq_size = sizeof (u32);
+ }
+ clib_memcpy (vlib_buffer_get_current (b0) + b0->current_length +
+ seq_size, icv, icv_size);
+ memset (icv, 0, icv_size);
+
+ ip_mutable_data_t *md =
+ (ip_mutable_data_t *) ((u8 *) vlib_buffer_get_current (b0) +
+ b0->current_length + seq_size +
+ icv_size);
+ if (is_ip6)
+ {
+ md->ip_version_traffic_class_and_flow_label =
+ ih6->ip_version_traffic_class_and_flow_label;
+ md->hop_limit = ih6->hop_limit;
+ ih6->ip_version_traffic_class_and_flow_label = 0x60;
+ ih6->hop_limit = 0;
+ }
+ else
+ {
+ md->tos = ih4->tos;
+ md->ttl = ih4->ttl;
+ ih4->tos = 0;
+ ih4->ttl = 0;
+ ih4->checksum = 0;
+ ih4->flags_and_fragment_offset = 0;
+ }
+
+ JOB_AES_HMAC *job = IPSECMB_FUNC (get_next_job) (mgr);
+ job->src = vlib_buffer_get_current (b0);
+ job->hash_start_src_offset_in_bytes = 0;
+ job->cipher_mode = NULL_CIPHER;
+ job->hash_alg = imbm->integ_algs[sa0->integ_alg].hash_alg;
+ job->auth_tag_output_len_in_bytes =
+ imbm->integ_algs[sa0->integ_alg].hash_output_length;
+ job->auth_tag_output = icv;
+ job->msg_len_to_hash_in_bytes = b0->current_length + seq_size;
+ job->cipher_direction = DECRYPT;
+ job->chain_order = HASH_CIPHER;
+ job->u.HMAC._hashed_auth_key_xor_ipad = samb0->ipad_hash;
+ job->u.HMAC._hashed_auth_key_xor_opad = samb0->opad_hash;
+
+ job->user_data = (void *) (uintptr_t) bi0;
+ job->user_data2 = (void *) (uintptr_t) next0;
+ vnet_buffer (b0)->ipsec.sad_index = sa_index0;
+ job = IPSECMB_FUNC (submit_job) (mgr);
+ ++packets_in_flight;
+
+ if (!job)
+ {
+ continue;
+ }
+ --packets_in_flight;
+ ASSERT (STS_COMPLETED == job->status);
+ ah_finish_decrypt (vm, node, job, &bi0, &next0, is_ip6);
+ }
+ else
+ {
+ remove_ah (vm, node, &bi0, &next0, sa0, ip_hdr_size, icv_size,
+ 0, ah0, is_ip6);
+ }
+ trace:
+ to_next[0] = bi0;
+ to_next += 1;
+ n_left_to_next -= 1;
+ if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+ {
+ b0->flags |= VLIB_BUFFER_IS_TRACED;
+ ah_decrypt_trace_t *tr =
+ vlib_add_trace (vm, node, b0, sizeof (*tr));
+ tr->integ_alg = sa0->integ_alg;
+ }
+ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+ n_left_to_next, bi0, next0);
+ }
+
+ if (0 == n_left_from)
+ {
+ JOB_AES_HMAC *job = NULL;
+ while (n_left_to_next > 0 && (job = IPSECMB_FUNC (flush_job) (mgr)))
+ {
+ --packets_in_flight;
+ ASSERT (STS_COMPLETED == job->status);
+ u32 bi0, next0;
+ ah_finish_decrypt (vm, node, job, &bi0, &next0, is_ip6);
+ to_next[0] = bi0;
+ to_next += 1;
+ n_left_to_next -= 1;
+ vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
+ if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+ {
+ ipsec_sa_t *sa0 = pool_elt_at_index (im->sad,
+ vnet_buffer
+ (b0)->ipsec.sad_index);
+ b0->flags |= VLIB_BUFFER_IS_TRACED;
+ ah_decrypt_trace_t *tr =
+ vlib_add_trace (vm, node, b0, sizeof (*tr));
+ tr->integ_alg = sa0->integ_alg;
+ }
+ 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, node->node_index, AH_DECRYPT_ERROR_RX_PKTS,
+ from_frame->n_vectors);
+
+ return from_frame->n_vectors;
+}
+
+VLIB_NODE_FN (ah4_decrypt_ipsecmb_node) (vlib_main_t * vm,
+ vlib_node_runtime_t * node,
+ vlib_frame_t * from_frame)
+{
+ return ah_decrypt_ipsecmb_inline (vm, node, from_frame, 0 /*is_ip6 */ );
+}
+
+VLIB_NODE_FN (ah6_decrypt_ipsecmb_node) (vlib_main_t * vm,
+ vlib_node_runtime_t * node,
+ vlib_frame_t * from_frame)
+{
+ return ah_decrypt_ipsecmb_inline (vm, node, from_frame, 1 /*is_ip6 */ );
+}
+#endif
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (ah4_decrypt_ipsecmb_node) = {
+ .name = "ah4-decrypt-ipsecmb",
+ .vector_size = sizeof (u32),
+ .format_trace = format_ah_decrypt_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+
+ .n_errors = ARRAY_LEN (ah_decrypt_error_strings),
+ .error_strings = ah_decrypt_error_strings,
+
+ .n_next_nodes = AH_DECRYPT_N_NEXT,
+ .next_nodes =
+ {
+#define _(s, n) [AH_DECRYPT_NEXT_##s] = n,
+ foreach_ah_decrypt_next
+#undef _
+ },
+};
+/* *INDENT-ON* */
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (ah6_decrypt_ipsecmb_node) = {
+ .name = "ah6-decrypt-ipsecmb",
+ .vector_size = sizeof (u32),
+ .format_trace = format_ah_decrypt_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+
+ .n_errors = ARRAY_LEN (ah_decrypt_error_strings),
+ .error_strings = ah_decrypt_error_strings,
+
+ .n_next_nodes = AH_DECRYPT_N_NEXT,
+ .next_nodes =
+ {
+#define _(s, n) [AH_DECRYPT_NEXT_##s] = n,
+ foreach_ah_decrypt_next
+#undef _
+ },
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */