aboutsummaryrefslogtreecommitdiff
path: root/net/colo.c
blob: 180eaed49afe97bcf9f4618e095d9ef68294132c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
/*
 * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
 * (a.k.a. Fault Tolerance or Continuous Replication)
 *
 * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
 * Copyright (c) 2016 FUJITSU LIMITED
 * Copyright (c) 2016 Intel Corporation
 *
 * Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or
 * later.  See the COPYING file in the top-level directory.
 */

#include "qemu/osdep.h"
#include "trace.h"
#include "net/colo.h"

uint32_t connection_key_hash(const void *opaque)
{
    const ConnectionKey *key = opaque;
    uint32_t a, b, c;

    /* Jenkins hash */
    a = b = c = JHASH_INITVAL + sizeof(*key);
    a += key->src.s_addr;
    b += key->dst.s_addr;
    c += (key->src_port | key->dst_port << 16);
    __jhash_mix(a, b, c);

    a += key->ip_proto;
    __jhash_final(a, b, c);

    return c;
}

int connection_key_equal(const void *key1, const void *key2)
{
    return memcmp(key1, key2, sizeof(ConnectionKey)) == 0;
}

int parse_packet_early(Packet *pkt)
{
    int network_length;
    static const uint8_t vlan[] = {0x81, 0x00};
    uint8_t *data = pkt->data;
    uint16_t l3_proto;
    ssize_t l2hdr_len = eth_get_l2_hdr_length(data);

    if (pkt->size < ETH_HLEN) {
        trace_colo_proxy_main("pkt->size < ETH_HLEN");
        return 1;
    }

    /*
     * TODO: support vlan.
     */
    if (!memcmp(&data[12], vlan, sizeof(vlan))) {
        trace_colo_proxy_main("COLO-proxy don't support vlan");
        return 1;
    }

    pkt->network_header = data + l2hdr_len;

    const struct iovec l2vec = {
        .iov_base = (void *) data,
        .iov_len = l2hdr_len
    };
    l3_proto = eth_get_l3_proto(&l2vec, 1, l2hdr_len);

    if (l3_proto != ETH_P_IP) {
        return 1;
    }

    network_length = pkt->ip->ip_hl * 4;
    if (pkt->size < l2hdr_len + network_length) {
        trace_colo_proxy_main("pkt->size < network_header + network_length");
        return 1;
    }
    pkt->transport_header = pkt->network_header + network_length;

    return 0;
}

void fill_connection_key(Packet *pkt, ConnectionKey *key)
{
    uint32_t tmp_ports;

    memset(key, 0, sizeof(*key));
    key->ip_proto = pkt->ip->ip_p;

    switch (key->ip_proto) {
    case IPPROTO_TCP:
    case IPPROTO_UDP:
    case IPPROTO_DCCP:
    case IPPROTO_ESP:
    case IPPROTO_SCTP:
    case IPPROTO_UDPLITE:
        tmp_ports = *(uint32_t *)(pkt->transport_header);
        key->src = pkt->ip->ip_src;
        key->dst = pkt->ip->ip_dst;
        key->src_port = ntohs(tmp_ports & 0xffff);
        key->dst_port = ntohs(tmp_ports >> 16);
        break;
    case IPPROTO_AH:
        tmp_ports = *(uint32_t *)(pkt->transport_header + 4);
        key->src = pkt->ip->ip_src;
        key->dst = pkt->ip->ip_dst;
        key->src_port = ntohs(tmp_ports & 0xffff);
        key->dst_port = ntohs(tmp_ports >> 16);
        break;
    default:
        break;
    }
}

void reverse_connection_key(ConnectionKey *key)
{
    struct in_addr tmp_ip;
    uint16_t tmp_port;

    tmp_ip = key->src;
    key->src = key->dst;
    key->dst = tmp_ip;

    tmp_port = key->src_port;
    key->src_port = key->dst_port;
    key->dst_port = tmp_port;
}

Connection *connection_new(ConnectionKey *key)
{
    Connection *conn = g_slice_new(Connection);

    conn->ip_proto = key->ip_proto;
    conn->processing = false;
    conn->offset = 0;
    conn->syn_flag = 0;
    g_queue_init(&conn->primary_list);
    g_queue_init(&conn->secondary_list);

    return conn;
}

void connection_destroy(void *opaque)
{
    Connection *conn = opaque;

    g_queue_foreach(&conn->primary_list, packet_destroy, NULL);
    g_queue_clear(&conn->primary_list);
    g_queue_foreach(&conn->secondary_list, packet_destroy, NULL);
    g_queue_clear(&conn->secondary_list);
    g_slice_free(Connection, conn);
}

Packet *packet_new(const void *data, int size, int vnet_hdr_len)
{
    Packet *pkt = g_slice_new(Packet);

    pkt->data = g_memdup(data, size);
    pkt->size = size;
    pkt->creation_ms = qemu_clock_get_ms(QEMU_CLOCK_HOST);
    pkt->vnet_hdr_len = vnet_hdr_len;

    return pkt;
}

void packet_destroy(void *opaque, void *user_data)
{
    Packet *pkt = opaque;

    g_free(pkt->data);
    g_slice_free(Packet, pkt);
}

/*
 * Clear hashtable, stop this hash growing really huge
 */
void connection_hashtable_reset(GHashTable *connection_track_table)
{
    g_hash_table_remove_all(connection_track_table);
}

/* if not found, create a new connection and add to hash table */
Connection *connection_get(GHashTable *connection_track_table,
                           ConnectionKey *key,
                           GQueue *conn_list)
{
    Connection *conn = g_hash_table_lookup(connection_track_table, key);

    if (conn == NULL) {
        ConnectionKey *new_key = g_memdup(key, sizeof(*key));

        conn = connection_new(key);

        if (g_hash_table_size(connection_track_table) > HASHTABLE_MAX_SIZE) {
            trace_colo_proxy_main("colo proxy connection hashtable full,"
                                  " clear it");
            connection_hashtable_reset(connection_track_table);
            /*
             * clear the conn_list
             */
            while (!g_queue_is_empty(conn_list)) {
                connection_destroy(g_queue_pop_head(conn_list));
            }
        }

        g_hash_table_insert(connection_track_table, new_key, conn);
    }

    return conn;
}