sniffer-agent/session-dealer/mysql/session.go

364 lines
9.2 KiB
Go

package mysql
import (
"fmt"
"strings"
"sync"
"time"
log "github.com/sirupsen/logrus"
"github.com/pingcap/tidb/util/hack"
"github.com/zr-hebo/sniffer-agent/model"
)
type MysqlSession struct {
connectionID *string
visitUser *string
visitDB *string
clientHost *string
clientPort int
serverIP *string
serverPort int
stmtBeginTime int64
beginSeqID int64
packageOffset int64
expectReceiveSize int
coverRanges []*jigsaw
expectSendSize int
prepareInfo *prepareInfo
cachedPrepareStmt map[int][]byte
cachedStmtBytes []byte
computeWindowSizeCounter int
tcpPacketCache []*model.TCPPacket
queryPieceReceiver chan model.QueryPiece
lastSeq int64
closeConn chan bool
pkgCacheLock sync.Mutex
ignoreAckID int64
sendSize int64
}
type prepareInfo struct {
prepareStmtID int
}
var (
windowSizeCache = make(map[string]*packageWindowCounter, 16)
)
const (
maxIPPackageSize = 1 << 16
)
func NewMysqlSession(
sessionKey *string, clientIP *string, clientPort int, serverIP *string, serverPort int,
receiver chan model.QueryPiece) (ms *MysqlSession) {
ms = &MysqlSession{
connectionID: sessionKey,
clientHost: clientIP,
clientPort: clientPort,
serverIP: serverIP,
serverPort: serverPort,
stmtBeginTime: time.Now().UnixNano() / millSecondUnit,
cachedPrepareStmt: make(map[int][]byte, 8),
coverRanges: make([]*jigsaw, 0, 4),
queryPieceReceiver: receiver,
closeConn: make(chan bool, 1),
lastSeq: -1,
ignoreAckID: -1,
sendSize: 0,
pkgCacheLock: sync.Mutex{},
}
return
}
func (ms *MysqlSession) ReceiveTCPPacket(newPkt *model.TCPPacket) {
if newPkt == nil {
return
}
if !newPkt.ToServer && ms.ignoreAckID == newPkt.Seq {
// ignore to response to client data
ms.ignoreAckID = ms.ignoreAckID + int64(len(newPkt.Payload))
return
} else if !newPkt.ToServer {
ms.ignoreAckID = newPkt.Seq + int64(len(newPkt.Payload))
}
if newPkt.ToServer {
ms.resetBeginTime()
ms.readFromClient(newPkt.Seq, newPkt.Payload)
} else {
ms.readFromServer(newPkt.Payload)
qp := ms.GenerateQueryPiece()
if qp != nil {
ms.queryPieceReceiver <- qp
}
}
}
func (ms *MysqlSession) resetBeginTime() {
ms.stmtBeginTime = time.Now().UnixNano() / millSecondUnit
}
func (ms *MysqlSession) readFromServer(bytes []byte) {
if ms.expectSendSize < 1 {
ms.expectSendSize = extractMysqlPayloadSize(bytes[:4])
contents := bytes[4:]
if ms.prepareInfo != nil && contents[0] == 0 {
ms.prepareInfo.prepareStmtID = bytesToInt(contents[1:5])
}
}
}
func (ms *MysqlSession) mergeRanges() {
if len(ms.coverRanges) > 1 {
newRange, newPkgRanges := mergeRanges(ms.coverRanges[0], ms.coverRanges[1:])
tmpRanges := make([]*jigsaw, len(newPkgRanges)+1)
tmpRanges[0] = newRange
if len(newPkgRanges) > 0 {
copy(tmpRanges[1:], newPkgRanges)
}
ms.coverRanges = tmpRanges
}
}
func mergeRanges(currRange *jigsaw, pkgRanges []*jigsaw) (mergedRange *jigsaw, newPkgRanges []*jigsaw) {
var nextRange *jigsaw
newPkgRanges = make([]*jigsaw, 0, 4)
if len(pkgRanges) < 1 {
return currRange, newPkgRanges
} else if len(pkgRanges) == 1 {
nextRange = pkgRanges[0]
} else {
nextRange, newPkgRanges = mergeRanges(pkgRanges[0], pkgRanges[1:])
}
if currRange.e >= nextRange.b {
mergedRange = &jigsaw{b: currRange.b, e: nextRange.e}
} else {
tmpRanges := make([]*jigsaw, len(newPkgRanges)+1)
tmpRanges[0] = nextRange
if len(newPkgRanges) > 0 {
copy(tmpRanges[1:], newPkgRanges)
}
newPkgRanges = tmpRanges
mergedRange = currRange
}
return
}
func (ms *MysqlSession) oneMysqlPackageFinish() bool {
if int64(len(ms.cachedStmtBytes))%MaxMysqlPacketLen == 0 {
return true
}
return false
}
func (ms *MysqlSession) checkFinish() bool {
if len(ms.coverRanges) != 1 {
ranges := make([]string, 0, len(ms.coverRanges))
for _, cr := range ms.coverRanges {
ranges = append(ranges, fmt.Sprintf("[%d -- %d]", cr.b, cr.e))
}
log.Debugf("in session %s get invalid range: %s", *ms.connectionID, strings.Join(ranges, ", "))
return false
}
firstRange := ms.coverRanges[0]
if firstRange.e-firstRange.b != int64(len(ms.cachedStmtBytes)) {
return false
}
return true
}
func (ms *MysqlSession) readFromClient(seqID int64, bytes []byte) {
contentSize := int64(len(bytes))
if ms.expectReceiveSize == 0 || ms.oneMysqlPackageFinish() {
ms.expectReceiveSize = extractMysqlPayloadSize(bytes[:4])
ms.packageOffset = int64(len(ms.cachedStmtBytes))
contents := bytes[4:]
if contents[0] == ComStmtPrepare {
ms.prepareInfo = &prepareInfo{}
}
contentSize = int64(len(contents))
seqID += 4
ms.beginSeqID = seqID
newCache := make([]byte, ms.expectReceiveSize+len(ms.cachedStmtBytes))
if len(ms.cachedStmtBytes) > 0 {
copy(newCache[:len(ms.cachedStmtBytes)], ms.cachedStmtBytes)
}
if int64(ms.expectReceiveSize+len(ms.cachedStmtBytes)) >= ms.packageOffset+int64(len(contents)) {
copy(newCache[ms.packageOffset:ms.packageOffset+int64(len(contents))], contents)
ms.cachedStmtBytes = newCache
}
} else {
if seqID < ms.beginSeqID {
log.Debugf("in session %s get outdate package with Seq:%d", *ms.connectionID, seqID)
return
}
seqOffset := seqID - ms.beginSeqID
if ms.packageOffset+seqOffset+int64(len(bytes)) <= int64(ms.expectReceiveSize) {
copy(ms.cachedStmtBytes[ms.packageOffset+seqOffset:ms.packageOffset+seqOffset+int64(len(bytes))], bytes)
}
}
insertIdx := len(ms.coverRanges)
for idx, cr := range ms.coverRanges {
if seqID < cr.b {
insertIdx = idx
break
}
}
cr := &jigsaw{b: seqID, e: seqID + contentSize}
if len(ms.coverRanges) < 1 || insertIdx == len(ms.coverRanges) {
ms.coverRanges = append(ms.coverRanges, cr)
} else {
newCoverRanges := make([]*jigsaw, len(ms.coverRanges)+1)
copy(newCoverRanges[:insertIdx], ms.coverRanges[:insertIdx])
newCoverRanges[insertIdx] = cr
copy(newCoverRanges[insertIdx+1:], ms.coverRanges[insertIdx:])
ms.coverRanges = newCoverRanges
}
ms.mergeRanges()
}
func (ms *MysqlSession) GenerateQueryPiece() (qp model.QueryPiece) {
defer func() {
ms.cachedStmtBytes = nil
ms.expectReceiveSize = 0
ms.expectSendSize = 0
ms.prepareInfo = nil
ms.coverRanges = make([]*jigsaw, 0, 4)
ms.lastSeq = -1
ms.ignoreAckID = -1
ms.sendSize = 0
}()
if len(ms.cachedStmtBytes) < 1 {
return
}
if !ms.checkFinish() {
log.Debugf("receive a not complete cover")
return
}
var mqp *model.PooledMysqlQueryPiece
var querySQLInBytes []byte
if ms.cachedStmtBytes[0] > 32 {
userName, dbName, err := parseAuthInfo(ms.cachedStmtBytes)
if err != nil {
log.Errorf("parse auth info failed <-- %s", err.Error())
return
}
ms.visitUser = &userName
ms.visitDB = &dbName
} else {
switch ms.cachedStmtBytes[0] {
case ComInitDB:
newDBName := string(ms.cachedStmtBytes[1:])
useSQL := fmt.Sprintf("use %s", newDBName)
querySQLInBytes = hack.Slice(useSQL)
mqp = ms.composeQueryPiece()
mqp.QuerySQL = &useSQL
// update session database
ms.visitDB = &newDBName
case ComDropDB:
dbName := string(ms.cachedStmtBytes[1:])
dropSQL := fmt.Sprintf("drop database %s", dbName)
mqp = ms.composeQueryPiece()
mqp.QuerySQL = &dropSQL
case ComCreateDB, ComQuery:
mqp = ms.composeQueryPiece()
querySQLInBytes = ms.cachedStmtBytes[1:]
querySQL := hack.String(querySQLInBytes)
mqp.QuerySQL = &querySQL
case ComStmtPrepare:
mqp = ms.composeQueryPiece()
querySQLInBytes = ms.cachedStmtBytes[1:]
querySQL := hack.String(querySQLInBytes)
mqp.QuerySQL = &querySQL
ms.cachedPrepareStmt[ms.prepareInfo.prepareStmtID] = querySQLInBytes
log.Debugf("prepare statement %s, get id:%d", querySQL, ms.prepareInfo.prepareStmtID)
case ComStmtExecute:
prepareStmtID := bytesToInt(ms.cachedStmtBytes[1:5])
mqp = ms.composeQueryPiece()
querySQLInBytes = ms.cachedPrepareStmt[prepareStmtID]
querySQL := hack.String(querySQLInBytes)
mqp.QuerySQL = &querySQL
log.Debugf("execute prepare statement:%d", prepareStmtID)
case ComStmtClose:
prepareStmtID := bytesToInt(ms.cachedStmtBytes[1:5])
delete(ms.cachedPrepareStmt, prepareStmtID)
log.Debugf("remove prepare statement:%d", prepareStmtID)
default:
return
}
}
if strictMode && mqp != nil && mqp.VisitUser == nil {
user, db, err := querySessionInfo(ms.serverPort, mqp.SessionID)
if err != nil {
log.Errorf("query user and db from mysql failed <-- %s", err.Error())
} else {
mqp.VisitUser = user
mqp.VisitDB = db
}
}
return filterQueryPieceBySQL(mqp, querySQLInBytes)
}
func filterQueryPieceBySQL(mqp *model.PooledMysqlQueryPiece, querySQL []byte) (model.QueryPiece) {
if mqp == nil || querySQL == nil {
return nil
} else if (uselessSQLPattern.Match(querySQL)) {
return nil
}
if ddlPatern.Match(querySQL) {
mqp.SetNeedSyncSend(true)
}
return mqp
}
func (ms *MysqlSession) composeQueryPiece() (mqp *model.PooledMysqlQueryPiece) {
return model.NewPooledMysqlQueryPiece(
ms.connectionID, ms.clientHost, ms.visitUser, ms.visitDB, ms.clientHost, ms.serverIP,
ms.clientPort, ms.serverPort, ms.stmtBeginTime)
}