*/
#include "qemu/osdep.h"
-#include "net/colo.h"
+#include "trace.h"
+#include "colo.h"
#include "net/filter.h"
#include "net/net.h"
#include "qemu-common.h"
-#include "qapi/error.h"
-#include "qapi/qmp/qerror.h"
-#include "qapi-visit.h"
+#include "qemu/error-report.h"
#include "qom/object.h"
#include "qemu/main-loop.h"
#include "qemu/iov.h"
#include "net/checksum.h"
+#include "net/colo.h"
+#include "migration/colo.h"
+#include "util.h"
#define FILTER_COLO_REWRITER(obj) \
OBJECT_CHECK(RewriterState, (obj), TYPE_FILTER_REWRITER)
#define TYPE_FILTER_REWRITER "filter-rewriter"
+#define FAILOVER_MODE_ON true
+#define FAILOVER_MODE_OFF false
typedef struct RewriterState {
NetFilterState parent_obj;
NetQueue *incoming_queue;
/* hashtable to save connection */
GHashTable *connection_track_table;
+ bool vnet_hdr;
+ bool failover_mode;
} RewriterState;
+static void filter_rewriter_failover_mode(RewriterState *s)
+{
+ s->failover_mode = FAILOVER_MODE_ON;
+}
+
static void filter_rewriter_flush(NetFilterState *nf)
{
RewriterState *s = FILTER_COLO_REWRITER(nf);
}
}
+/* handle tcp packet from primary guest */
+static int handle_primary_tcp_pkt(RewriterState *rf,
+ Connection *conn,
+ Packet *pkt, ConnectionKey *key)
+{
+ struct tcp_hdr *tcp_pkt;
+
+ tcp_pkt = (struct tcp_hdr *)pkt->transport_header;
+ if (trace_event_get_state_backends(TRACE_COLO_FILTER_REWRITER_DEBUG)) {
+ trace_colo_filter_rewriter_pkt_info(__func__,
+ inet_ntoa(pkt->ip->ip_src), inet_ntoa(pkt->ip->ip_dst),
+ ntohl(tcp_pkt->th_seq), ntohl(tcp_pkt->th_ack),
+ tcp_pkt->th_flags);
+ trace_colo_filter_rewriter_conn_offset(conn->offset);
+ }
+
+ if (((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == (TH_ACK | TH_SYN)) &&
+ conn->tcp_state == TCPS_SYN_SENT) {
+ conn->tcp_state = TCPS_ESTABLISHED;
+ }
+
+ if (((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_SYN)) {
+ /*
+ * we use this flag update offset func
+ * run once in independent tcp connection
+ */
+ conn->tcp_state = TCPS_SYN_RECEIVED;
+ }
+
+ if (((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_ACK)) {
+ if (conn->tcp_state == TCPS_SYN_RECEIVED) {
+ /*
+ * offset = secondary_seq - primary seq
+ * ack packet sent by guest from primary node,
+ * so we use th_ack - 1 get primary_seq
+ */
+ conn->offset -= (ntohl(tcp_pkt->th_ack) - 1);
+ conn->tcp_state = TCPS_ESTABLISHED;
+ }
+ if (conn->offset) {
+ /* handle packets to the secondary from the primary */
+ tcp_pkt->th_ack = htonl(ntohl(tcp_pkt->th_ack) + conn->offset);
+
+ net_checksum_calculate((uint8_t *)pkt->data + pkt->vnet_hdr_len,
+ pkt->size - pkt->vnet_hdr_len);
+ }
+
+ /*
+ * Passive close step 3
+ */
+ if ((conn->tcp_state == TCPS_LAST_ACK) &&
+ (ntohl(tcp_pkt->th_ack) == (conn->fin_ack_seq + 1))) {
+ conn->tcp_state = TCPS_CLOSED;
+ g_hash_table_remove(rf->connection_track_table, key);
+ }
+ }
+
+ if ((tcp_pkt->th_flags & TH_FIN) == TH_FIN) {
+ /*
+ * Passive close.
+ * Step 1:
+ * The *server* side of this connect is VM, *client* tries to close
+ * the connection. We will into CLOSE_WAIT status.
+ *
+ * Step 2:
+ * In this step we will into LAST_ACK status.
+ *
+ * We got 'fin=1, ack=1' packet from server side, we need to
+ * record the seq of 'fin=1, ack=1' packet.
+ *
+ * Step 3:
+ * We got 'ack=1' packets from client side, it acks 'fin=1, ack=1'
+ * packet from server side. From this point, we can ensure that there
+ * will be no packets in the connection, except that, some errors
+ * happen between the path of 'filter object' and vNIC, if this rare
+ * case really happen, we can still create a new connection,
+ * So it is safe to remove the connection from connection_track_table.
+ *
+ */
+ if (conn->tcp_state == TCPS_ESTABLISHED) {
+ conn->tcp_state = TCPS_CLOSE_WAIT;
+ }
+
+ /*
+ * Active close step 2.
+ */
+ if (conn->tcp_state == TCPS_FIN_WAIT_1) {
+ /*
+ * For simplify implementation, we needn't wait 2MSL time
+ * in filter rewriter. Because guest kernel will track the
+ * TCP status and wait 2MSL time, if client resend the FIN
+ * packet, guest will apply the last ACK too.
+ * So, we skip the TCPS_TIME_WAIT state here and go straight
+ * to TCPS_CLOSED state.
+ */
+ conn->tcp_state = TCPS_CLOSED;
+ g_hash_table_remove(rf->connection_track_table, key);
+ }
+ }
+
+ return 0;
+}
+
+/* handle tcp packet from secondary guest */
+static int handle_secondary_tcp_pkt(RewriterState *rf,
+ Connection *conn,
+ Packet *pkt, ConnectionKey *key)
+{
+ struct tcp_hdr *tcp_pkt;
+
+ tcp_pkt = (struct tcp_hdr *)pkt->transport_header;
+
+ if (trace_event_get_state_backends(TRACE_COLO_FILTER_REWRITER_DEBUG)) {
+ trace_colo_filter_rewriter_pkt_info(__func__,
+ inet_ntoa(pkt->ip->ip_src), inet_ntoa(pkt->ip->ip_dst),
+ ntohl(tcp_pkt->th_seq), ntohl(tcp_pkt->th_ack),
+ tcp_pkt->th_flags);
+ trace_colo_filter_rewriter_conn_offset(conn->offset);
+ }
+
+ if (conn->tcp_state == TCPS_SYN_RECEIVED &&
+ ((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == (TH_ACK | TH_SYN))) {
+ /*
+ * save offset = secondary_seq and then
+ * in handle_primary_tcp_pkt make offset
+ * = secondary_seq - primary_seq
+ */
+ conn->offset = ntohl(tcp_pkt->th_seq);
+ }
+
+ /* VM active connect */
+ if (conn->tcp_state == TCPS_CLOSED &&
+ ((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_SYN)) {
+ conn->tcp_state = TCPS_SYN_SENT;
+ }
+
+ if ((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_ACK) {
+ /* Only need to adjust seq while offset is Non-zero */
+ if (conn->offset) {
+ /* handle packets to the primary from the secondary*/
+ tcp_pkt->th_seq = htonl(ntohl(tcp_pkt->th_seq) - conn->offset);
+
+ net_checksum_calculate((uint8_t *)pkt->data + pkt->vnet_hdr_len,
+ pkt->size - pkt->vnet_hdr_len);
+ }
+ }
+
+ /*
+ * Passive close step 2:
+ */
+ if (conn->tcp_state == TCPS_CLOSE_WAIT &&
+ (tcp_pkt->th_flags & (TH_ACK | TH_FIN)) == (TH_ACK | TH_FIN)) {
+ conn->fin_ack_seq = ntohl(tcp_pkt->th_seq);
+ conn->tcp_state = TCPS_LAST_ACK;
+ }
+
+ /*
+ * Active close
+ *
+ * Step 1:
+ * The *server* side of this connect is VM, *server* tries to close
+ * the connection.
+ *
+ * Step 2:
+ * We will into CLOSE_WAIT status.
+ * We simplify the TCPS_FIN_WAIT_2, TCPS_TIME_WAIT and
+ * CLOSING status.
+ */
+ if (conn->tcp_state == TCPS_ESTABLISHED &&
+ (tcp_pkt->th_flags & (TH_ACK | TH_FIN)) == TH_FIN) {
+ conn->tcp_state = TCPS_FIN_WAIT_1;
+ }
+
+ return 0;
+}
+
static ssize_t colo_rewriter_receive_iov(NetFilterState *nf,
NetClientState *sender,
unsigned flags,
ConnectionKey key;
Packet *pkt;
ssize_t size = iov_size(iov, iovcnt);
+ ssize_t vnet_hdr_len = 0;
char *buf = g_malloc0(size);
iov_to_buf(iov, iovcnt, 0, buf, size);
- pkt = packet_new(buf, size);
+
+ if (s->vnet_hdr) {
+ vnet_hdr_len = nf->netdev->vnet_hdr_len;
+ }
+
+ pkt = packet_new(buf, size, vnet_hdr_len);
+ g_free(buf);
/*
* if we get tcp packet
*/
reverse_connection_key(&key);
}
+
+ /* After failover we needn't change new TCP packet */
+ if (s->failover_mode &&
+ !connection_has_tracked(s->connection_track_table, &key)) {
+ goto out;
+ }
+
conn = connection_get(s->connection_track_table,
&key,
NULL);
if (sender == nf->netdev) {
/* NET_FILTER_DIRECTION_TX */
- /* handle_primary_tcp_pkt */
+ if (!handle_primary_tcp_pkt(s, conn, pkt, &key)) {
+ qemu_net_queue_send(s->incoming_queue, sender, 0,
+ (const uint8_t *)pkt->data, pkt->size, NULL);
+ packet_destroy(pkt, NULL);
+ pkt = NULL;
+ /*
+ * We block the packet here,after rewrite pkt
+ * and will send it
+ */
+ return 1;
+ }
} else {
/* NET_FILTER_DIRECTION_RX */
- /* handle_secondary_tcp_pkt */
+ if (!handle_secondary_tcp_pkt(s, conn, pkt, &key)) {
+ qemu_net_queue_send(s->incoming_queue, sender, 0,
+ (const uint8_t *)pkt->data, pkt->size, NULL);
+ packet_destroy(pkt, NULL);
+ pkt = NULL;
+ /*
+ * We block the packet here,after rewrite pkt
+ * and will send it
+ */
+ return 1;
+ }
}
}
+out:
packet_destroy(pkt, NULL);
pkt = NULL;
return 0;
}
+static void reset_seq_offset(gpointer key, gpointer value, gpointer user_data)
+{
+ Connection *conn = (Connection *)value;
+
+ conn->offset = 0;
+}
+
+static gboolean offset_is_nonzero(gpointer key,
+ gpointer value,
+ gpointer user_data)
+{
+ Connection *conn = (Connection *)value;
+
+ return conn->offset ? true : false;
+}
+
+static void colo_rewriter_handle_event(NetFilterState *nf, int event,
+ Error **errp)
+{
+ RewriterState *rs = FILTER_COLO_REWRITER(nf);
+
+ switch (event) {
+ case COLO_EVENT_CHECKPOINT:
+ g_hash_table_foreach(rs->connection_track_table,
+ reset_seq_offset, NULL);
+ break;
+ case COLO_EVENT_FAILOVER:
+ if (!g_hash_table_find(rs->connection_track_table,
+ offset_is_nonzero, NULL)) {
+ filter_rewriter_failover_mode(rs);
+ }
+ break;
+ default:
+ break;
+ }
+}
+
static void colo_rewriter_cleanup(NetFilterState *nf)
{
RewriterState *s = FILTER_COLO_REWRITER(nf);
s->incoming_queue = qemu_new_net_queue(qemu_netfilter_pass_to_next, nf);
}
+static bool filter_rewriter_get_vnet_hdr(Object *obj, Error **errp)
+{
+ RewriterState *s = FILTER_COLO_REWRITER(obj);
+
+ return s->vnet_hdr;
+}
+
+static void filter_rewriter_set_vnet_hdr(Object *obj,
+ bool value,
+ Error **errp)
+{
+ RewriterState *s = FILTER_COLO_REWRITER(obj);
+
+ s->vnet_hdr = value;
+}
+
+static void filter_rewriter_init(Object *obj)
+{
+ RewriterState *s = FILTER_COLO_REWRITER(obj);
+
+ s->vnet_hdr = false;
+ s->failover_mode = FAILOVER_MODE_OFF;
+ object_property_add_bool(obj, "vnet_hdr_support",
+ filter_rewriter_get_vnet_hdr,
+ filter_rewriter_set_vnet_hdr, NULL);
+}
+
static void colo_rewriter_class_init(ObjectClass *oc, void *data)
{
NetFilterClass *nfc = NETFILTER_CLASS(oc);
nfc->setup = colo_rewriter_setup;
nfc->cleanup = colo_rewriter_cleanup;
nfc->receive_iov = colo_rewriter_receive_iov;
+ nfc->handle_event = colo_rewriter_handle_event;
}
static const TypeInfo colo_rewriter_info = {
.name = TYPE_FILTER_REWRITER,
.parent = TYPE_NETFILTER,
.class_init = colo_rewriter_class_init,
+ .instance_init = filter_rewriter_init,
.instance_size = sizeof(RewriterState),
};
projects / mirror_qemu.git / blobdiff