xref: /openbmc/qemu/net/colo.h (revision 438c78da)
1 /*
2  * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
3  * (a.k.a. Fault Tolerance or Continuous Replication)
4  *
5  * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
6  * Copyright (c) 2016 FUJITSU LIMITED
7  * Copyright (c) 2016 Intel Corporation
8  *
9  * Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
10  *
11  * This work is licensed under the terms of the GNU GPL, version 2 or
12  * later.  See the COPYING file in the top-level directory.
13  */
14 
15 #ifndef QEMU_COLO_PROXY_H
16 #define QEMU_COLO_PROXY_H
17 
18 #include "slirp/slirp.h"
19 #include "qemu/jhash.h"
20 #include "qemu/timer.h"
21 #include "slirp/tcp.h"
22 
23 #define HASHTABLE_MAX_SIZE 16384
24 
25 #ifndef IPPROTO_DCCP
26 #define IPPROTO_DCCP 33
27 #endif
28 
29 #ifndef IPPROTO_SCTP
30 #define IPPROTO_SCTP 132
31 #endif
32 
33 #ifndef IPPROTO_UDPLITE
34 #define IPPROTO_UDPLITE 136
35 #endif
36 
37 typedef struct Packet {
38     void *data;
39     union {
40         uint8_t *network_header;
41         struct ip *ip;
42     };
43     uint8_t *transport_header;
44     int size;
45     /* Time of packet creation, in wall clock ms */
46     int64_t creation_ms;
47     /* Get vnet_hdr_len from filter */
48     uint32_t vnet_hdr_len;
49     uint32_t tcp_seq; /* sequence number */
50     uint32_t tcp_ack; /* acknowledgement number */
51     /* the sequence number of the last byte of the packet */
52     uint32_t seq_end;
53     uint8_t header_size;  /* the header length */
54     uint16_t payload_size; /* the payload length */
55     /* record the payload offset(the length that has been compared) */
56     uint16_t offset;
57     uint8_t flags; /* Flags(aka Control bits) */
58 } Packet;
59 
60 typedef struct ConnectionKey {
61     /* (src, dst) must be grouped, in the same way than in IP header */
62     struct in_addr src;
63     struct in_addr dst;
64     uint16_t src_port;
65     uint16_t dst_port;
66     uint8_t ip_proto;
67 } QEMU_PACKED ConnectionKey;
68 
69 typedef struct Connection {
70     /* connection primary send queue: element type: Packet */
71     GQueue primary_list;
72     /* connection secondary send queue: element type: Packet */
73     GQueue secondary_list;
74     /* flag to enqueue unprocessed_connections */
75     bool processing;
76     uint8_t ip_proto;
77     /* record the sequence number that has been compared */
78     uint32_t compare_seq;
79     /* the maximum of acknowledgement number in primary_list queue */
80     uint32_t pack;
81     /* the maximum of acknowledgement number in secondary_list queue */
82     uint32_t sack;
83     /* offset = secondary_seq - primary_seq */
84     tcp_seq  offset;
85 
86     int tcp_state; /* TCP FSM state */
87     tcp_seq fin_ack_seq; /* the seq of 'fin=1,ack=1' */
88 } Connection;
89 
90 uint32_t connection_key_hash(const void *opaque);
91 int connection_key_equal(const void *opaque1, const void *opaque2);
92 int parse_packet_early(Packet *pkt);
93 void extract_ip_and_port(uint32_t tmp_ports, ConnectionKey *key, Packet *pkt);
94 void fill_connection_key(Packet *pkt, ConnectionKey *key);
95 void reverse_connection_key(ConnectionKey *key);
96 Connection *connection_new(ConnectionKey *key);
97 void connection_destroy(void *opaque);
98 Connection *connection_get(GHashTable *connection_track_table,
99                            ConnectionKey *key,
100                            GQueue *conn_list);
101 bool connection_has_tracked(GHashTable *connection_track_table,
102                             ConnectionKey *key);
103 void connection_hashtable_reset(GHashTable *connection_track_table);
104 Packet *packet_new(const void *data, int size, int vnet_hdr_len);
105 void packet_destroy(void *opaque, void *user_data);
106 
107 #endif /* QEMU_COLO_PROXY_H */
108