Add initial code

The inital code is from this patch:
https://gerrit.fd.io/r/#/c/vpp/+/16580/
It is contributed by Intel and Travelping.
Jerome Tollet, Ed Warnicke, Dave Barach, Damjan Marion from Cisco
and other guys have gave lots of useful comments on it.

The initial code is used for identifying layer-7 applications for HTTPS/TLS traffic

- Below is the brief design info.

- Provides a default APPID database for scan.

- Dynamically create new SW mapping has been supported now.

- Support TCP connection state tracking.

- Support TCP segments reassembly on the fly, which handles out-of-order tcp segments and overlapping segments.
  It means that we do not need to reassembly segments first, then dedect applicaion,
  and then fragment segments again, which helps to improve performance.

- Support Hyperscan Stream mode, which can scan rules straddling into different tcp segments.
  It means that if there is a rule "abcde", then "abc" can be in packet 1,
  and "de" can be in packet 2.

- Configure static dpi flows with 5-tuple and VRF-aware, and supports both ipv4 and ipv6 flows.
  These flows will first try to HW offload to NIC based on DPDK rte_flow mechanism
  and vpp/vnet/flow infrastructure.
  If failed, then will create static SW flow mappings.
  Each flow configuration will create two HW or SW flow mappings, i.e. for forward and reverse traffic.
  And both flow mappings will be mapped to the same dpi flow.
  SW entry aging out mechanism will be added later.
        "dpi flow [add | del]  "
        "[src-ip <ip-addr>] [dst-ip <ip-addr>] "
        "[src-port <port>] [dst-port <port>] "
        "[protocol <protocol>] [vrf-id <nn>]",
        "dpi set flow-offload hw <interface-name> rx <flow-id> [del]",
        "dpi set ip4 flow-bypass <interface> [del]",

- When HW flow offload matched, packets will be redirected to DPI plugin with dpi flow_id in packet descriptor.
   If not, packets will be bypassed to DPI plugin from ip-input, and then lookup SW flow mapping table.

- Then will detect layer 7 applications.
   This first patch only detect sub protocls within SSL/TLS.
   1). Identify SSL/TLS certificate message and subsequent segments.
   2). Scan SSL/TLS certificate message through hyperscan, and get application id if matched.
   3). If maximum packets for this flow are checked and not found matched application, the detection will end up.

Ticket:
Type: feature

Signed-off-by: Hongjun Ni <hongjun.ni@intel.com>
Signed-off-by: Andreas Schultz <andreas.schultz@travelping.com>
Signed-off-by: Mathias Gumz <mathias.gumz@travelping.com>
Change-Id: I839cc70ddc80ea594d22a04e2cabf92a7b9c74e7

1 files changed, 330 insertions, 0 deletions

diff --git a/src/dpi.h b/src/dpi.h
new file mode 100644
index 0000000..e3d0add
--- /dev/null
+++ b/src/dpi.h
@@ -0,0 +1,330 @@
+/*
+ *------------------------------------------------------------------
+ * Copyright (c) 2018 Intel, Travelping 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.
+ *------------------------------------------------------------------
+ */
+
+#ifndef included_vnet_dpi_h
+#define included_vnet_dpi_h
+
+#include <vppinfra/lock.h>
+#include <vppinfra/error.h>
+#include <vppinfra/hash.h>
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/ip/ip4_packet.h>
+#include <vnet/ip/ip6_packet.h>
+#include <vnet/udp/udp.h>
+#include <vnet/dpo/dpo.h>
+#include <vppinfra/bihash_8_8.h>
+#include <vppinfra/bihash_24_8.h>
+#include <vppinfra/bihash_48_8.h>
+
+#include <hs/hs.h>
+#include <hs/hs_common.h>
+#include <hs/hs_compile.h>
+#include <hs/hs_runtime.h>
+#include "dpi_app_match.h"
+
+typedef u8 *regex_t;
+
+typedef struct
+{
+  u8 *name;
+  regex_t *expressions;
+  u32 *flags;
+  u32 *ids;
+  hs_database_t *database;
+  hs_scratch_t *scratch;
+  u32 ref_cnt;
+} dpi_entry_t;
+
+typedef struct
+{
+  int res;
+  u32 id;
+} dpi_cb_args_t;
+
+typedef struct
+{
+  union
+  {
+    struct
+    {
+      ip46_address_t src_ip;
+      ip46_address_t dst_ip;
+      u16 src_port;
+      u16 dst_port;
+      u8 protocol;
+      u32 fib_index;
+    };
+    u64 key[6];
+  };
+} dpi_flow_key_t;
+
+typedef clib_bihash_kv_24_8_t dpi4_flow_key_t;
+typedef clib_bihash_kv_48_8_t dpi6_flow_key_t;
+
+typedef struct
+{
+  /* SSL */
+  u8 ssl_stage;
+  u8 ssl_got_server_cert;
+} dpi_flow_tcp_t;
+
+typedef struct
+{
+  /* TBD */
+} dpi_flow_udp_t;
+
+typedef struct segment_
+{
+  u32 send_sn;
+  u8 *data;
+  u32 len;
+  u32 bi;			/* vlib buffer index */
+  struct segment_ *next;
+} segment;
+
+typedef struct tcp_stream_
+{
+  u32 send_sn;			/* expected segment sn */
+  u32 ack_sn;			/* acked segment sn */
+  segment *seg_queue;		/* store out-of-order segments */
+} tcp_stream_t;
+
+typedef struct dpi_flow_info
+{
+  /* Required for pool_get_aligned  */
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+
+  u16 detected_protocol[2];
+  u16 protocol_stack_info;
+  u16 pkt_num;
+  u16 pkt_direct_counter[2];
+
+  hs_stream_t *stream;
+  u8 detect_begin;
+  u8 detect_done;
+  u32 app_id;			/* L7 APP ID */
+
+  u16 guessed_protocol_id;
+  u16 guessed_host_protocol_id;
+
+  u8 max_more_pkts_to_check;
+
+  int (*more_pkts_func) (u8 * payload, u32 payload_len,
+			 struct dpi_flow_info * flow);
+
+  u16 dst_port;
+  u8 l4_protocol;
+  union
+  {
+    dpi_flow_tcp_t tcp;
+    dpi_flow_udp_t udp;
+  } l4;
+
+  u8 ssl_cert_detected:4;
+  u8 ssl_cert_num_checks:4;
+
+  union
+  {
+    struct
+    {
+      char server_cert[64];
+    } ssl;
+    /* TBD: Add more protocols */
+  } protos;
+} dpi_flow_info_t;
+
+typedef enum
+{
+  TCP_STATE_SYN = 1,
+  TCP_STATE_SYN_ACK = 2,
+  TCP_STATE_ACK = 3,
+  TCP_STATE_ESTABLISH = 4,
+  TCP_STATE_FIN1 = 5,
+  TCP_STATE_CLOSE = 6,
+} tcp_state_t;
+
+/* tcp packet direction */
+#define DIR_C2S 0
+#define DIR_S2C 1
+
+/* tcp reassembly side */
+#define REASS_C2S 0
+#define REASS_S2C 1
+#define REASS_BOTH 2
+
+/* Macros to handle sequence numbers */
+#define SN_LT(a,b)  ((int)((a) - (b)) <  0)
+#define SN_GT(a,b)  ((int)((a) - (b)) >  0)
+#define SN_EQ(a,b)  ((int)((a) - (b)) == 0)
+
+typedef struct
+{
+  /* Required for pool_get_aligned  */
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+
+  u32 flow_index;		/* infra flow index */
+  u32 next_index;
+
+  u8 check_more_pkts:1;
+  u8 pkt_dir:1;
+  u8 forward_is_c2s:1;
+  u8 consumed:1;
+  u8 reass_en:1;
+  u8 reass_dir:2;
+
+  dpi_flow_key_t key;
+  dpi_flow_info_t *info;
+
+  /* TCP stream reassembly */
+  tcp_state_t tcp_state;
+  tcp_stream_t c2s;
+  tcp_stream_t s2c;
+  segment *first_seg;
+
+} dpi_flow_entry_t;
+
+typedef struct
+{
+  u32 flow_id;
+  u8 reass_en;
+  u8 reass_dir;
+} tcp_reass_args_t;
+
+typedef struct
+{
+  u8 is_add;
+  u8 is_ipv6;
+  ip46_address_t src_ip;
+  ip46_address_t dst_ip;
+  u16 src_port;
+  u16 dst_port;
+  u8 protocol;
+  u32 fib_index;
+} dpi_add_del_flow_args_t;
+
+typedef struct
+{
+  u32 app_id;
+  u32 db_id;
+} dpi_adr_t;
+
+typedef struct
+{
+  /* lookup tunnel by key */
+  clib_bihash_24_8_t dpi4_flow_by_key;
+  clib_bihash_48_8_t dpi6_flow_by_key;
+
+  /* vector of dpi flow instances */
+  dpi_flow_entry_t *dpi_flows;
+  u32 flow_id_start;
+  dpi_flow_info_t *dpi_infos;
+  segment *seg_pool;
+
+  /* Default hyperscan database */
+  dpi_entry_t default_db;
+
+  /* graph node state */
+  uword *bm_ip4_bypass_enabled_by_sw_if;
+  uword *bm_ip6_bypass_enabled_by_sw_if;
+
+  /* API message ID base */
+  u16 msg_id_base;
+
+  /* convenience */
+  vlib_main_t *vlib_main;
+  vnet_main_t *vnet_main;
+} dpi_main_t;
+
+extern dpi_main_t dpi_main;
+
+#define foreach_copy_field              \
+_(src_ip)                               \
+_(dst_ip)                               \
+_(src_port)                             \
+_(dst_port)                             \
+_(protocol)                             \
+_(fib_index)
+
+
+#define dpi_enqueue_tcp_segments(seg,vm,node,next_index,to_next,n_left_to_next,bi0,next0) \
+while(seg)        \
+  {               \
+    bi0 = seg->bi;  \
+    to_next[0] = bi0; \
+    to_next++;        \
+    n_left_to_next--; \
+    next0 = flow0->next_index;         \
+    vlib_validate_buffer_enqueue_x1 (vm, node, next_index,  \
+                     to_next, n_left_to_next,   \
+                     bi0, next0);   \
+    prev_seg = seg;  \
+    seg=seg->next;   \
+    pool_put(dm->seg_pool, prev_seg);  \
+  }
+
+
+#define get_u16_t(X,O)  (*(u16 *)(((u8 *)X) + O))
+#define DPI_MAX_SSL_REQUEST_SIZE 10000
+
+int dpi_flow_add_del (dpi_add_del_flow_args_t * a, u32 * flow_idp);
+int dpi_reverse_flow_add_del (dpi_add_del_flow_args_t * a, u32 flow_id);
+int dpi_add_del_rx_flow (u32 hw_if_index, u32 flow_id, int is_add,
+			 u32 is_ipv6);
+int dpi_tcp_reass (tcp_reass_args_t * a);
+void dpi_flow_bypass_mode (u32 sw_if_index, u8 is_ip6, u8 is_enable);
+int dpi_search_host_protocol (dpi_flow_info_t * flow,
+			      char *str_to_match,
+			      u32 str_to_match_len,
+			      u16 master_protocol_id, u32 * host_protocol_id);
+void dpi_search_tcp_ssl (u8 * payload, u32 payload_len,
+			 dpi_flow_info_t * flow);
+
+void dpi_detect_application (u8 * payload, u32 payload_len,
+			     dpi_flow_info_t * flow);
+
+typedef enum
+{
+  DPI_PROTOCOL_UNKNOWN = 0,
+  DPI_PROTOCOL_SSL = 1,
+  DPI_PROTOCOL_SSL_NO_CERT = 2,
+  DPI_N_PROTOCOL
+} dpi_protocol_id_t;
+
+#define foreach_dpi_input_next        \
+_(DROP, "error-drop")                 \
+_(IP4_LOOKUP, "ip4-lookup")
+
+typedef enum
+{
+#define _(s,n) DPI_INPUT_NEXT_##s,
+  foreach_dpi_input_next
+#undef _
+    DPI_INPUT_N_NEXT,
+} dpi_input_next_t;
+
+#endif /* included_vnet_dpi_h */
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */