VPP-598: tcp stack initial commit

Change-Id: I49e5ce0aae6e4ff634024387ceaf7dbc432a0351
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Florin Coras <fcoras@cisco.com>

1 files changed, 184 insertions, 0 deletions

diff --git a/src/vnet/tcp/tcp_packet.h b/src/vnet/tcp/tcp_packet.h
new file mode 100644
index 00000000000..866c5fd6046
--- /dev/null
+++ b/src/vnet/tcp/tcp_packet.h
@@ -0,0 +1,184 @@
+/*
+ * Copyright (c) 2016 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.
+ */
+
+#ifndef included_tcp_packet_h
+#define included_tcp_packet_h
+
+#include <vnet/vnet.h>
+
+/* TCP flags bit 0 first. */
+#define foreach_tcp_flag                                \
+  _ (FIN) /**< No more data from sender. */             \
+  _ (SYN) /**< Synchronize sequence numbers. */         \
+  _ (RST) /**< Reset the connection. */                 \
+  _ (PSH) /**< Push function. */                        \
+  _ (ACK) /**< Ack field significant. */                \
+  _ (URG) /**< Urgent pointer field significant. */     \
+  _ (ECE) /**< ECN-echo. Receiver got CE packet */      \
+  _ (CWR) /**< Sender reduced congestion window */
+
+enum
+{
+#define _(f) TCP_FLAG_BIT_##f,
+  foreach_tcp_flag
+#undef _
+    TCP_N_FLAG_BITS,
+};
+
+enum
+{
+#define _(f) TCP_FLAG_##f = 1 << TCP_FLAG_BIT_##f,
+  foreach_tcp_flag
+#undef _
+};
+
+typedef struct _tcp_header
+{
+  union
+  {
+    struct
+    {
+      u16 src_port; /**< Source port. */
+      u16 dst_port; /**< Destination port. */
+    };
+    struct
+    {
+      u16 src, dst;
+    };
+  };
+
+  u32 seq_number;	/**< Sequence number of the first data octet in this
+                         *   segment, except when SYN is present. If SYN
+                         *   is present the seq number is is the ISN and the
+                         *   first data octet is ISN+1 */
+  u32 ack_number;	/**< Acknowledgement number if ACK is set. It contains
+                         *   the value of the next sequence number the sender
+                         *   of the segment is expecting to receive. */
+  u8 data_offset_and_reserved;
+  u8 flags;		/**< Flags: see the macro above */
+  u16 window;		/**< Number of bytes sender is willing to receive. */
+
+  u16 checksum;		/**< Checksum of TCP pseudo header and data. */
+  u16 urgent_pointer;	/**< Seq number of the byte after the urgent data. */
+} __attribute__ ((packed)) tcp_header_t;
+
+/* Flag tests that return 0 or !0 */
+#define tcp_doff(_th) ((_th)->data_offset_and_reserved >> 4)
+#define tcp_fin(_th) ((_th)->flags & TCP_FLAG_FIN)
+#define tcp_syn(_th) ((_th)->flags & TCP_FLAG_SYN)
+#define tcp_rst(_th) ((_th)->flags & TCP_FLAG_RST)
+#define tcp_psh(_th) ((_th)->flags & TCP_FLAG_PSH)
+#define tcp_ack(_th) ((_th)->flags & TCP_FLAG_ACK)
+#define tcp_urg(_th) ((_th)->flags & TCP_FLAG_URG)
+#define tcp_ece(_th) ((_th)->flags & TCP_FLAG_ECE)
+#define tcp_cwr(_th) ((_th)->flags & TCP_FLAG_CWR)
+
+/* Flag tests that return 0 or 1 */
+#define tcp_is_syn(_th) !!((_th)->flags & TCP_FLAG_SYN)
+#define tcp_is_fin(_th) !!((_th)->flags & TCP_FLAG_FIN)
+
+always_inline int
+tcp_header_bytes (tcp_header_t * t)
+{
+  return tcp_doff (t) * sizeof (u32);
+}
+
+/*
+ * TCP options.
+ */
+
+typedef enum tcp_option_type
+{
+  TCP_OPTION_EOL = 0,			/**< End of options. */
+  TCP_OPTION_NOOP = 1,			/**< No operation. */
+  TCP_OPTION_MSS = 2,			/**< Limit MSS. */
+  TCP_OPTION_WINDOW_SCALE = 3,		/**< Window scale. */
+  TCP_OPTION_SACK_PERMITTED = 4,	/**< Selective Ack permitted. */
+  TCP_OPTION_SACK_BLOCK = 5,		/**< Selective Ack block. */
+  TCP_OPTION_TIMESTAMP = 8,		/**< Timestamps. */
+  TCP_OPTION_UTO = 28,			/**< User timeout. */
+  TCP_OPTION_AO = 29,			/**< Authentication Option. */
+} tcp_option_type_t;
+
+#define foreach_tcp_options_flag                                        \
+  _ (MSS)               /**< MSS advertised in SYN */                   \
+  _ (TSTAMP)            /**< Timestamp capability advertised in SYN */  \
+  _ (WSCALE)            /**< Wnd scale capability advertised in SYN */  \
+  _ (SACK_PERMITTED)    /**< SACK capability advertised in SYN */       \
+  _ (SACK)		/**< SACK present */
+
+enum
+{
+#define _(f) TCP_OPTS_FLAG_BIT_##f,
+  foreach_tcp_options_flag
+#undef _
+    TCP_OPTIONS_N_FLAG_BITS,
+};
+
+enum
+{
+#define _(f) TCP_OPTS_FLAG_##f = 1 << TCP_OPTS_FLAG_BIT_##f,
+  foreach_tcp_options_flag
+#undef _
+};
+
+typedef struct _sack_block
+{
+  u32 start;		/**< Start sequence number */
+  u32 end;		/**< End sequence number */
+} sack_block_t;
+
+typedef struct
+{
+  u8 flags;		/** Option flags, see above */
+
+  /* Received options */
+  u16 mss;		/**< Maximum segment size advertised by peer */
+  u8 wscale;		/**< Window scale advertised by peer */
+  u32 tsval;		/**< Peer's timestamp value */
+  u32 tsecr;		/**< Echoed/reflected time stamp */
+  sack_block_t *sacks;	/**< SACK blocks received */
+  u8 n_sack_blocks;	/**< Number of SACKs blocks */
+} tcp_options_t;
+
+/* Flag tests that return 0 or !0 */
+#define tcp_opts_mss(_to) ((_to)->flags & TCP_OPTS_FLAG_MSS)
+#define tcp_opts_tstamp(_to) ((_to)->flags & TCP_OPTS_FLAG_TSTAMP)
+#define tcp_opts_wscale(_to) ((_to)->flags & TCP_OPTS_FLAG_WSCALE)
+#define tcp_opts_sack(_to) ((_to)->flags & TCP_OPTS_FLAG_SACK)
+#define tcp_opts_sack_permitted(_to) ((_to)->flags & TCP_OPTS_FLAG_SACK_PERMITTED)
+
+/* TCP option lengths */
+#define TCP_OPTION_LEN_EOL              1
+#define TCP_OPTION_LEN_NOOP             1
+#define TCP_OPTION_LEN_MSS              4
+#define TCP_OPTION_LEN_WINDOW_SCALE     3
+#define TCP_OPTION_LEN_SACK_PERMITTED   2
+#define TCP_OPTION_LEN_TIMESTAMP        10
+#define TCP_OPTION_LEN_SACK_BLOCK        8
+
+#define TCP_WND_MAX                     65535U
+#define TCP_MAX_WND_SCALE               14	/* See RFC 1323 */
+#define TCP_OPTS_ALIGN                  4
+#define TCP_OPTS_MAX_SACK_BLOCKS        3
+#endif /* included_tcp_packet_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */