Merge remote-tracking branch 'remotes/jsnow-gitlab/tags/python-pull-request' into...
[qemu.git] / net / colo.c
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 #include "qemu/osdep.h"
16 #include "trace.h"
17 #include "colo.h"
18 #include "util.h"
19
20 uint32_t connection_key_hash(const void *opaque)
21 {
22 const ConnectionKey *key = opaque;
23 uint32_t a, b, c;
24
25 /* Jenkins hash */
26 a = b = c = JHASH_INITVAL + sizeof(*key);
27 a += key->src.s_addr;
28 b += key->dst.s_addr;
29 c += (key->src_port | key->dst_port << 16);
30 __jhash_mix(a, b, c);
31
32 a += key->ip_proto;
33 __jhash_final(a, b, c);
34
35 return c;
36 }
37
38 int connection_key_equal(const void *key1, const void *key2)
39 {
40 return memcmp(key1, key2, sizeof(ConnectionKey)) == 0;
41 }
42
43 int parse_packet_early(Packet *pkt)
44 {
45 int network_length;
46 static const uint8_t vlan[] = {0x81, 0x00};
47 uint8_t *data = pkt->data + pkt->vnet_hdr_len;
48 uint16_t l3_proto;
49 ssize_t l2hdr_len = eth_get_l2_hdr_length(data);
50
51 if (pkt->size < ETH_HLEN + pkt->vnet_hdr_len) {
52 trace_colo_proxy_main("pkt->size < ETH_HLEN");
53 return 1;
54 }
55
56 /*
57 * TODO: support vlan.
58 */
59 if (!memcmp(&data[12], vlan, sizeof(vlan))) {
60 trace_colo_proxy_main("COLO-proxy don't support vlan");
61 return 1;
62 }
63
64 pkt->network_header = data + l2hdr_len;
65
66 const struct iovec l2vec = {
67 .iov_base = (void *) data,
68 .iov_len = l2hdr_len
69 };
70 l3_proto = eth_get_l3_proto(&l2vec, 1, l2hdr_len);
71
72 if (l3_proto != ETH_P_IP) {
73 return 1;
74 }
75
76 network_length = pkt->ip->ip_hl * 4;
77 if (pkt->size < l2hdr_len + network_length + pkt->vnet_hdr_len) {
78 trace_colo_proxy_main("pkt->size < network_header + network_length");
79 return 1;
80 }
81 pkt->transport_header = pkt->network_header + network_length;
82
83 return 0;
84 }
85
86 void extract_ip_and_port(uint32_t tmp_ports, ConnectionKey *key, Packet *pkt)
87 {
88 key->src = pkt->ip->ip_src;
89 key->dst = pkt->ip->ip_dst;
90 key->src_port = ntohs(tmp_ports >> 16);
91 key->dst_port = ntohs(tmp_ports & 0xffff);
92 }
93
94 void fill_connection_key(Packet *pkt, ConnectionKey *key)
95 {
96 uint32_t tmp_ports;
97
98 memset(key, 0, sizeof(*key));
99 key->ip_proto = pkt->ip->ip_p;
100
101 switch (key->ip_proto) {
102 case IPPROTO_TCP:
103 case IPPROTO_UDP:
104 case IPPROTO_DCCP:
105 case IPPROTO_ESP:
106 case IPPROTO_SCTP:
107 case IPPROTO_UDPLITE:
108 tmp_ports = *(uint32_t *)(pkt->transport_header);
109 extract_ip_and_port(tmp_ports, key, pkt);
110 break;
111 case IPPROTO_AH:
112 tmp_ports = *(uint32_t *)(pkt->transport_header + 4);
113 extract_ip_and_port(tmp_ports, key, pkt);
114 break;
115 default:
116 break;
117 }
118 }
119
120 void reverse_connection_key(ConnectionKey *key)
121 {
122 struct in_addr tmp_ip;
123 uint16_t tmp_port;
124
125 tmp_ip = key->src;
126 key->src = key->dst;
127 key->dst = tmp_ip;
128
129 tmp_port = key->src_port;
130 key->src_port = key->dst_port;
131 key->dst_port = tmp_port;
132 }
133
134 Connection *connection_new(ConnectionKey *key)
135 {
136 Connection *conn = g_slice_new0(Connection);
137
138 conn->ip_proto = key->ip_proto;
139 conn->processing = false;
140 conn->tcp_state = TCPS_CLOSED;
141 g_queue_init(&conn->primary_list);
142 g_queue_init(&conn->secondary_list);
143
144 return conn;
145 }
146
147 void connection_destroy(void *opaque)
148 {
149 Connection *conn = opaque;
150
151 g_queue_foreach(&conn->primary_list, packet_destroy, NULL);
152 g_queue_clear(&conn->primary_list);
153 g_queue_foreach(&conn->secondary_list, packet_destroy, NULL);
154 g_queue_clear(&conn->secondary_list);
155 g_slice_free(Connection, conn);
156 }
157
158 Packet *packet_new(const void *data, int size, int vnet_hdr_len)
159 {
160 Packet *pkt = g_slice_new0(Packet);
161
162 pkt->data = g_memdup(data, size);
163 pkt->size = size;
164 pkt->creation_ms = qemu_clock_get_ms(QEMU_CLOCK_HOST);
165 pkt->vnet_hdr_len = vnet_hdr_len;
166
167 return pkt;
168 }
169
170 /*
171 * packet_new_nocopy will not copy data, so the caller can't release
172 * the data. And it will be released in packet_destroy.
173 */
174 Packet *packet_new_nocopy(void *data, int size, int vnet_hdr_len)
175 {
176 Packet *pkt = g_slice_new0(Packet);
177
178 pkt->data = data;
179 pkt->size = size;
180 pkt->creation_ms = qemu_clock_get_ms(QEMU_CLOCK_HOST);
181 pkt->vnet_hdr_len = vnet_hdr_len;
182
183 return pkt;
184 }
185
186 void packet_destroy(void *opaque, void *user_data)
187 {
188 Packet *pkt = opaque;
189
190 g_free(pkt->data);
191 g_slice_free(Packet, pkt);
192 }
193
194 void packet_destroy_partial(void *opaque, void *user_data)
195 {
196 Packet *pkt = opaque;
197
198 g_slice_free(Packet, pkt);
199 }
200
201 /*
202 * Clear hashtable, stop this hash growing really huge
203 */
204 void connection_hashtable_reset(GHashTable *connection_track_table)
205 {
206 g_hash_table_remove_all(connection_track_table);
207 }
208
209 /* if not found, create a new connection and add to hash table */
210 Connection *connection_get(GHashTable *connection_track_table,
211 ConnectionKey *key,
212 GQueue *conn_list)
213 {
214 Connection *conn = g_hash_table_lookup(connection_track_table, key);
215
216 if (conn == NULL) {
217 ConnectionKey *new_key = g_memdup(key, sizeof(*key));
218
219 conn = connection_new(key);
220
221 if (g_hash_table_size(connection_track_table) > HASHTABLE_MAX_SIZE) {
222 trace_colo_proxy_main("colo proxy connection hashtable full,"
223 " clear it");
224 connection_hashtable_reset(connection_track_table);
225 /*
226 * clear the conn_list
227 */
228 while (!g_queue_is_empty(conn_list)) {
229 connection_destroy(g_queue_pop_head(conn_list));
230 }
231 }
232
233 g_hash_table_insert(connection_track_table, new_key, conn);
234 }
235
236 return conn;
237 }
238
239 bool connection_has_tracked(GHashTable *connection_track_table,
240 ConnectionKey *key)
241 {
242 Connection *conn = g_hash_table_lookup(connection_track_table, key);
243
244 return conn ? true : false;
245 }