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
20uint32_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
38int connection_key_equal(const void *key1, const void *key2)
39{
40 return memcmp(key1, key2, sizeof(ConnectionKey)) == 0;
41}
42
43int 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
86void 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
94void 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
120void 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
134Connection *connection_new(ConnectionKey *key)
135{
136 Connection *conn = g_slice_new(Connection);
137
138 conn->ip_proto = key->ip_proto;
139 conn->processing = false;
140 conn->offset = 0;
141 conn->tcp_state = TCPS_CLOSED;
142 conn->pack = 0;
143 conn->sack = 0;
144 g_queue_init(&conn->primary_list);
145 g_queue_init(&conn->secondary_list);
146
147 return conn;
148}
149
150void connection_destroy(void *opaque)
151{
152 Connection *conn = opaque;
153
154 g_queue_foreach(&conn->primary_list, packet_destroy, NULL);
155 g_queue_clear(&conn->primary_list);
156 g_queue_foreach(&conn->secondary_list, packet_destroy, NULL);
157 g_queue_clear(&conn->secondary_list);
158 g_slice_free(Connection, conn);
159}
160
161Packet *packet_new(const void *data, int size, int vnet_hdr_len)
162{
163 Packet *pkt = g_slice_new(Packet);
164
165 pkt->data = g_memdup(data, size);
166 pkt->size = size;
167 pkt->creation_ms = qemu_clock_get_ms(QEMU_CLOCK_HOST);
168 pkt->vnet_hdr_len = vnet_hdr_len;
169 pkt->tcp_seq = 0;
170 pkt->tcp_ack = 0;
171 pkt->seq_end = 0;
172 pkt->header_size = 0;
173 pkt->payload_size = 0;
174 pkt->offset = 0;
175 pkt->flags = 0;
176
177 return pkt;
178}
179
180void packet_destroy(void *opaque, void *user_data)
181{
182 Packet *pkt = opaque;
183
184 g_free(pkt->data);
185 g_slice_free(Packet, pkt);
186}
187
188/*
189 * Clear hashtable, stop this hash growing really huge
190 */
191void connection_hashtable_reset(GHashTable *connection_track_table)
192{
193 g_hash_table_remove_all(connection_track_table);
194}
195
196/* if not found, create a new connection and add to hash table */
197Connection *connection_get(GHashTable *connection_track_table,
198 ConnectionKey *key,
199 GQueue *conn_list)
200{
201 Connection *conn = g_hash_table_lookup(connection_track_table, key);
202
203 if (conn == NULL) {
204 ConnectionKey *new_key = g_memdup(key, sizeof(*key));
205
206 conn = connection_new(key);
207
208 if (g_hash_table_size(connection_track_table) > HASHTABLE_MAX_SIZE) {
209 trace_colo_proxy_main("colo proxy connection hashtable full,"
210 " clear it");
211 connection_hashtable_reset(connection_track_table);
212 /*
213 * clear the conn_list
214 */
215 while (!g_queue_is_empty(conn_list)) {
216 connection_destroy(g_queue_pop_head(conn_list));
217 }
218 }
219
220 g_hash_table_insert(connection_track_table, new_key, conn);
221 }
222
223 return conn;
224}
225
226bool connection_has_tracked(GHashTable *connection_track_table,
227 ConnectionKey *key)
228{
229 Connection *conn = g_hash_table_lookup(connection_track_table, key);
230
231 return conn ? true : false;
232}
233