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-rw-r--r--src/vnet/tcp/tcp_packet.h184
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diff --git a/src/vnet/tcp/tcp_packet.h b/src/vnet/tcp/tcp_packet.h
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+/*
+ * 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 (first outside) */
+} sack_block_t;
+
+typedef struct
+{
+ u8 flags; /** Option flags, see above */
+
+ u16 mss; /**< Maximum segment size advertised */
+ u8 wscale; /**< Window scale advertised */
+ u32 tsval; /**< Timestamp value */
+ u32 tsecr; /**< Echoed/reflected time stamp */
+ sack_block_t *sacks; /**< SACK blocks */
+ 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_HDR_LEN_MAX 60
+#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:
+ */