-
Notifications
You must be signed in to change notification settings - Fork 4.9k
/
procs.go
339 lines (285 loc) · 9.11 KB
/
procs.go
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
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
// Licensed to Elasticsearch B.V. under one or more contributor
// license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright
// ownership. Elasticsearch B.V. licenses this file to you under
// the Apache License, Version 2.0 (the "License"); you may
// not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
package procs
import (
"net"
"path/filepath"
"strings"
"time"
"github.com/elastic/beats/v7/libbeat/common"
"github.com/elastic/beats/v7/libbeat/logp"
"github.com/elastic/beats/v7/packetbeat/protos/applayer"
"github.com/elastic/go-sysinfo"
)
// This controls how often process info for a running process is reloaded
// A big value means less unnecessary refreshes at a higher risk of missing
// a PID being recycled by the OS
const processCacheExpiration = time.Second * 30
var (
anyIPv4 = net.IPv4zero.String()
anyIPv6 = net.IPv6unspecified.String()
)
type endpoint struct {
address string
port uint16
}
type portProcMapping struct {
endpoint endpoint
pid int
proc *process
}
type process struct {
pid, ppid int
name, exe, cwd string
args []string
startTime time.Time
// To control cache expiration
expiration time.Time
}
// Allow the OS-dependent implementation to be replaced by a mock for testing
type processWatcherImpl interface {
// GetLocalPortToPIDMapping returns the list of local port numbers and the PID
// that owns them.
GetLocalPortToPIDMapping(transport applayer.Transport) (ports map[endpoint]int, err error)
// GetProcess returns the process metadata.
GetProcess(pid int) *process
// GetLocalIPs returns the list of local addresses.
GetLocalIPs() ([]net.IP, error)
}
type ProcessesWatcher struct {
portProcMap map[applayer.Transport]map[endpoint]portProcMapping
localAddrs []net.IP
processCache map[int]*process
// config
enabled bool
procConfig []ProcConfig
impl processWatcherImpl
}
func (proc *ProcessesWatcher) Init(config ProcsConfig) error {
return proc.initWithImpl(config, proc)
}
func (proc *ProcessesWatcher) initWithImpl(config ProcsConfig, impl processWatcherImpl) error {
proc.impl = impl
proc.portProcMap = map[applayer.Transport]map[endpoint]portProcMapping{
applayer.TransportUDP: make(map[endpoint]portProcMapping),
applayer.TransportTCP: make(map[endpoint]portProcMapping),
}
proc.processCache = make(map[int]*process)
proc.enabled = config.Enabled
if proc.enabled {
logp.Info("Process watcher enabled")
} else {
logp.Info("Process watcher disabled")
}
// Read the local IP addresses
var err error
proc.localAddrs, err = impl.GetLocalIPs()
if err != nil {
logp.Err("Error getting local IP addresses: %s", err)
proc.localAddrs = []net.IP{}
}
proc.procConfig = config.Monitored
return nil
}
// FindProcessesTupleTCP looks up local process information for the source and
// destination addresses of TCP tuple
func (proc *ProcessesWatcher) FindProcessesTupleTCP(tuple *common.IPPortTuple) (procTuple *common.ProcessTuple) {
return proc.FindProcessesTuple(tuple, applayer.TransportTCP)
}
// FindProcessesTupleUDP looks up local process information for the source and
// destination addresses of UDP tuple
func (proc *ProcessesWatcher) FindProcessesTupleUDP(tuple *common.IPPortTuple) (procTuple *common.ProcessTuple) {
return proc.FindProcessesTuple(tuple, applayer.TransportUDP)
}
// FindProcessesTuple looks up local process information for the source and
// destination addresses of a tuple for the given transport protocol
func (proc *ProcessesWatcher) FindProcessesTuple(tuple *common.IPPortTuple, transport applayer.Transport) (procTuple *common.ProcessTuple) {
procTuple = &common.ProcessTuple{}
if !proc.enabled {
return
}
if proc.isLocalIP(tuple.SrcIP) {
if p := proc.findProc(tuple.SrcIP, tuple.SrcPort, transport); p != nil {
procTuple.Src.PID = p.pid
procTuple.Src.PPID = p.ppid
procTuple.Src.Name = p.name
procTuple.Src.Args = p.args
procTuple.Src.Exe = p.exe
procTuple.Src.StartTime = p.startTime
if logp.IsDebug("procs") {
logp.Debug("procs", "Found process '%s' (pid=%d) for %s:%d/%s", p.name, p.pid, tuple.SrcIP, tuple.SrcPort, transport)
}
}
}
if proc.isLocalIP(tuple.DstIP) {
if p := proc.findProc(tuple.DstIP, tuple.DstPort, transport); p != nil {
procTuple.Dst.PID = p.pid
procTuple.Dst.PPID = p.ppid
procTuple.Dst.Name = p.name
procTuple.Dst.Args = p.args
procTuple.Dst.Exe = p.exe
procTuple.Dst.StartTime = p.startTime
if logp.IsDebug("procs") {
logp.Debug("procs", "Found process '%s' (pid=%d) for %s:%d/%s", p.name, p.pid, tuple.DstIP, tuple.DstPort, transport)
}
}
}
return
}
func (proc *ProcessesWatcher) findProc(address net.IP, port uint16, transport applayer.Transport) *process {
defer logp.Recover("FindProc exception")
procMap, ok := proc.portProcMap[transport]
if !ok {
return nil
}
p, exists := lookupMapping(address, port, procMap)
if exists {
return p.proc
}
proc.updateMap(transport)
p, exists = lookupMapping(address, port, procMap)
if exists {
return p.proc
}
return nil
}
func lookupMapping(address net.IP, port uint16, procMap map[endpoint]portProcMapping) (p portProcMapping, found bool) {
// Precedence when one socket is bound to a specific IP:port and another one
// to INADDR_ANY and same port is not clear. Seems that the last one to bind
// takes precedence, and we don't have a way to tell.
// This function takes the naive approach of giving precedence to the more
// specific address and then to INADDR_ANY.
if p, found = procMap[endpoint{address.String(), port}]; found {
return
}
nullAddr := anyIPv4
if asIPv4 := address.To4(); asIPv4 == nil {
nullAddr = anyIPv6
}
p, found = procMap[endpoint{nullAddr, port}]
return
}
func (proc *ProcessesWatcher) updateMap(transport applayer.Transport) {
if logp.HasSelector("procsdetailed") {
start := time.Now()
defer func() {
logp.Debug("procsdetailed", "updateMap() took %v", time.Since(start))
}()
}
endpoints, err := proc.impl.GetLocalPortToPIDMapping(transport)
if err != nil {
logp.Err("unable to list local ports: %v", err)
}
proc.expireProcessCache()
for e, pid := range endpoints {
proc.updateMappingEntry(transport, e, pid)
}
}
func (proc *ProcessesWatcher) updateMappingEntry(transport applayer.Transport, e endpoint, pid int) {
prev, ok := proc.portProcMap[transport][e]
if ok && prev.pid == pid {
// This port->pid mapping already exists
return
}
p := proc.getProcessInfo(pid)
if p == nil {
return
}
// Simply overwrite old entries for now.
// We never expire entries from this map. Since there are 65k possible
// ports, the size of the dict can be max 1.5 MB, which we consider
// reasonable.
proc.portProcMap[transport][e] = portProcMapping{endpoint: e, pid: pid, proc: p}
if logp.IsDebug("procsdetailed") {
logp.Debug("procsdetailed", "updateMappingEntry(): local=%s:%d/%s pid=%d process='%s'",
e.address, e.port, transport, pid, p.name)
}
}
func (proc *ProcessesWatcher) isLocalIP(ip net.IP) bool {
if ip.IsLoopback() {
return true
}
for _, addr := range proc.localAddrs {
if ip.Equal(addr) {
return true
}
}
return false
}
func (proc *ProcessesWatcher) getProcessInfo(pid int) *process {
if p, ok := proc.processCache[pid]; ok {
return p
}
// Not in cache, resolve process info
p := proc.impl.GetProcess(pid)
if p == nil {
return nil
}
// The packetbeat.procs.monitored*.cmdline_grep allows you to overwrite
// the process name with an alias.
for _, match := range proc.procConfig {
if strings.Contains(strings.Join(p.args, " "), match.CmdlineGrep) {
p.name = match.Process
break
}
}
proc.processCache[pid] = p
return p
}
func (proc *ProcessesWatcher) expireProcessCache() {
now := time.Now()
for pid, info := range proc.processCache {
if now.After(info.expiration) {
delete(proc.processCache, pid)
}
}
}
// GetProcess returns the process metadata.
func (proc *ProcessesWatcher) GetProcess(pid int) *process {
if pid <= 0 {
return nil
}
p, err := sysinfo.Process(pid)
if err != nil {
logp.Err("Unable to get command-line for PID %d: %v", pid, err)
return nil
}
info, err := p.Info()
if err != nil {
logp.Err("Unable to get command-line for PID %d: %v", pid, err)
return nil
}
name := info.Name
if len(info.Args) > 0 {
// Workaround the 20 char limit on comm values on Linux.
name = filepath.Base(info.Args[0])
}
return &process{
pid: info.PID,
ppid: info.PPID,
name: name,
exe: info.Exe,
cwd: info.CWD,
args: info.Args,
startTime: info.StartTime,
expiration: time.Now().Add(processCacheExpiration),
}
}
// GetLocalIPs returns the list of local addresses.
func (proc *ProcessesWatcher) GetLocalIPs() ([]net.IP, error) {
return common.LocalIPAddrs()
}