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
|
// SPDX-License-Identifier: GPL-3.0-or-later
package fail2ban
import (
"bufio"
"bytes"
"errors"
"fmt"
"strconv"
"strings"
"time"
)
func (f *Fail2Ban) collect() (map[string]int64, error) {
now := time.Now()
if now.Sub(f.lastDiscoverTime) > f.discoverEvery || f.forceDiscover {
jails, err := f.discoverJails()
if err != nil {
return nil, err
}
f.jails = jails
f.lastDiscoverTime = now
f.forceDiscover = false
}
mx := make(map[string]int64)
if err := f.collectJails(mx); err != nil {
return nil, err
}
return mx, nil
}
func (f *Fail2Ban) discoverJails() ([]string, error) {
bs, err := f.exec.status()
if err != nil {
return nil, err
}
jails, err := parseFail2banStatus(bs)
if err != nil {
return nil, err
}
if len(jails) == 0 {
return nil, errors.New("no jails found")
}
f.Debugf("discovered %d jails: %v", len(jails), jails)
return jails, nil
}
func (f *Fail2Ban) collectJails(mx map[string]int64) error {
seen := make(map[string]bool)
for _, jail := range f.jails {
f.Debugf("querying status for jail '%s'", jail)
bs, err := f.exec.jailStatus(jail)
if err != nil {
if errors.Is(err, errJailNotExist) {
f.forceDiscover = true
continue
}
return err
}
failed, banned, err := parseFail2banJailStatus(bs)
if err != nil {
return err
}
if !f.seenJails[jail] {
f.seenJails[jail] = true
f.addJailCharts(jail)
}
seen[jail] = true
px := fmt.Sprintf("jail_%s_", jail)
mx[px+"currently_failed"] = failed
mx[px+"currently_banned"] = banned
}
for jail := range f.seenJails {
if !seen[jail] {
delete(f.seenJails, jail)
f.removeJailCharts(jail)
}
}
return nil
}
func parseFail2banJailStatus(jailStatus []byte) (failed, banned int64, err error) {
const (
failedSub = "Currently failed:"
bannedSub = "Currently banned:"
)
var failedFound, bannedFound bool
sc := bufio.NewScanner(bytes.NewReader(jailStatus))
for sc.Scan() && !(failedFound && bannedFound) {
text := strings.TrimSpace(sc.Text())
if text == "" {
continue
}
if !failedFound {
if i := strings.Index(text, failedSub); i != -1 {
failedFound = true
s := strings.TrimSpace(text[i+len(failedSub):])
if failed, err = strconv.ParseInt(s, 10, 64); err != nil {
return 0, 0, fmt.Errorf("failed to parse currently failed value (%s): %v", s, err)
}
}
}
if !bannedFound {
if i := strings.Index(text, bannedSub); i != -1 {
bannedFound = true
s := strings.TrimSpace(text[i+len(bannedSub):])
if banned, err = strconv.ParseInt(s, 10, 64); err != nil {
return 0, 0, fmt.Errorf("failed to parse currently banned value (%s): %v", s, err)
}
}
}
}
if !failedFound || !bannedFound {
return 0, 0, errors.New("failed to find failed and banned values")
}
return failed, banned, nil
}
func parseFail2banStatus(status []byte) ([]string, error) {
const sub = "Jail list:"
var jails []string
sc := bufio.NewScanner(bytes.NewReader(status))
for sc.Scan() {
text := strings.TrimSpace(sc.Text())
if i := strings.Index(text, sub); i != -1 {
s := strings.ReplaceAll(text[i+len(sub):], ",", "")
jails = strings.Fields(s)
break
}
}
if len(jails) == 0 {
return nil, errors.New("failed to find jails")
}
return jails, nil
}
|
