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
|
package netlink
import (
"fmt"
"net"
"github.com/vishvananda/netlink/nl"
"golang.org/x/sys/unix"
)
const FibRuleInvert = 0x2
// RuleAdd adds a rule to the system.
// Equivalent to: ip rule add
func RuleAdd(rule *Rule) error {
return pkgHandle.RuleAdd(rule)
}
// RuleAdd adds a rule to the system.
// Equivalent to: ip rule add
func (h *Handle) RuleAdd(rule *Rule) error {
req := h.newNetlinkRequest(unix.RTM_NEWRULE, unix.NLM_F_CREATE|unix.NLM_F_EXCL|unix.NLM_F_ACK)
return ruleHandle(rule, req)
}
// RuleDel deletes a rule from the system.
// Equivalent to: ip rule del
func RuleDel(rule *Rule) error {
return pkgHandle.RuleDel(rule)
}
// RuleDel deletes a rule from the system.
// Equivalent to: ip rule del
func (h *Handle) RuleDel(rule *Rule) error {
req := h.newNetlinkRequest(unix.RTM_DELRULE, unix.NLM_F_ACK)
return ruleHandle(rule, req)
}
func ruleHandle(rule *Rule, req *nl.NetlinkRequest) error {
msg := nl.NewRtMsg()
msg.Family = unix.AF_INET
msg.Protocol = unix.RTPROT_BOOT
msg.Scope = unix.RT_SCOPE_UNIVERSE
msg.Table = unix.RT_TABLE_UNSPEC
msg.Type = unix.RTN_UNSPEC
if req.NlMsghdr.Flags&unix.NLM_F_CREATE > 0 {
msg.Type = unix.RTN_UNICAST
}
if rule.Invert {
msg.Flags |= FibRuleInvert
}
if rule.Family != 0 {
msg.Family = uint8(rule.Family)
}
if rule.Table >= 0 && rule.Table < 256 {
msg.Table = uint8(rule.Table)
}
var dstFamily uint8
var rtAttrs []*nl.RtAttr
if rule.Dst != nil && rule.Dst.IP != nil {
dstLen, _ := rule.Dst.Mask.Size()
msg.Dst_len = uint8(dstLen)
msg.Family = uint8(nl.GetIPFamily(rule.Dst.IP))
dstFamily = msg.Family
var dstData []byte
if msg.Family == unix.AF_INET {
dstData = rule.Dst.IP.To4()
} else {
dstData = rule.Dst.IP.To16()
}
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.RTA_DST, dstData))
}
if rule.Src != nil && rule.Src.IP != nil {
msg.Family = uint8(nl.GetIPFamily(rule.Src.IP))
if dstFamily != 0 && dstFamily != msg.Family {
return fmt.Errorf("source and destination ip are not the same IP family")
}
srcLen, _ := rule.Src.Mask.Size()
msg.Src_len = uint8(srcLen)
var srcData []byte
if msg.Family == unix.AF_INET {
srcData = rule.Src.IP.To4()
} else {
srcData = rule.Src.IP.To16()
}
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.RTA_SRC, srcData))
}
req.AddData(msg)
for i := range rtAttrs {
req.AddData(rtAttrs[i])
}
native := nl.NativeEndian()
if rule.Priority >= 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.Priority))
req.AddData(nl.NewRtAttr(nl.FRA_PRIORITY, b))
}
if rule.Mark >= 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.Mark))
req.AddData(nl.NewRtAttr(nl.FRA_FWMARK, b))
}
if rule.Mask >= 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.Mask))
req.AddData(nl.NewRtAttr(nl.FRA_FWMASK, b))
}
if rule.Flow >= 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.Flow))
req.AddData(nl.NewRtAttr(nl.FRA_FLOW, b))
}
if rule.TunID > 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.TunID))
req.AddData(nl.NewRtAttr(nl.FRA_TUN_ID, b))
}
if rule.Table >= 256 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.Table))
req.AddData(nl.NewRtAttr(nl.FRA_TABLE, b))
}
if msg.Table > 0 {
if rule.SuppressPrefixlen >= 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.SuppressPrefixlen))
req.AddData(nl.NewRtAttr(nl.FRA_SUPPRESS_PREFIXLEN, b))
}
if rule.SuppressIfgroup >= 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.SuppressIfgroup))
req.AddData(nl.NewRtAttr(nl.FRA_SUPPRESS_IFGROUP, b))
}
}
if rule.IifName != "" {
req.AddData(nl.NewRtAttr(nl.FRA_IIFNAME, []byte(rule.IifName)))
}
if rule.OifName != "" {
req.AddData(nl.NewRtAttr(nl.FRA_OIFNAME, []byte(rule.OifName)))
}
if rule.Goto >= 0 {
msg.Type = nl.FR_ACT_GOTO
b := make([]byte, 4)
native.PutUint32(b, uint32(rule.Goto))
req.AddData(nl.NewRtAttr(nl.FRA_GOTO, b))
}
_, err := req.Execute(unix.NETLINK_ROUTE, 0)
return err
}
// RuleList lists rules in the system.
// Equivalent to: ip rule list
func RuleList(family int) ([]Rule, error) {
return pkgHandle.RuleList(family)
}
// RuleList lists rules in the system.
// Equivalent to: ip rule list
func (h *Handle) RuleList(family int) ([]Rule, error) {
req := h.newNetlinkRequest(unix.RTM_GETRULE, unix.NLM_F_DUMP|unix.NLM_F_REQUEST)
msg := nl.NewIfInfomsg(family)
req.AddData(msg)
msgs, err := req.Execute(unix.NETLINK_ROUTE, unix.RTM_NEWRULE)
if err != nil {
return nil, err
}
native := nl.NativeEndian()
var res = make([]Rule, 0)
for i := range msgs {
msg := nl.DeserializeRtMsg(msgs[i])
attrs, err := nl.ParseRouteAttr(msgs[i][msg.Len():])
if err != nil {
return nil, err
}
rule := NewRule()
rule.Invert = msg.Flags&FibRuleInvert > 0
for j := range attrs {
switch attrs[j].Attr.Type {
case unix.RTA_TABLE:
rule.Table = int(native.Uint32(attrs[j].Value[0:4]))
case nl.FRA_SRC:
rule.Src = &net.IPNet{
IP: attrs[j].Value,
Mask: net.CIDRMask(int(msg.Src_len), 8*len(attrs[j].Value)),
}
case nl.FRA_DST:
rule.Dst = &net.IPNet{
IP: attrs[j].Value,
Mask: net.CIDRMask(int(msg.Dst_len), 8*len(attrs[j].Value)),
}
case nl.FRA_FWMARK:
rule.Mark = int(native.Uint32(attrs[j].Value[0:4]))
case nl.FRA_FWMASK:
rule.Mask = int(native.Uint32(attrs[j].Value[0:4]))
case nl.FRA_TUN_ID:
rule.TunID = uint(native.Uint64(attrs[j].Value[0:4]))
case nl.FRA_IIFNAME:
rule.IifName = string(attrs[j].Value[:len(attrs[j].Value)-1])
case nl.FRA_OIFNAME:
rule.OifName = string(attrs[j].Value[:len(attrs[j].Value)-1])
case nl.FRA_SUPPRESS_PREFIXLEN:
i := native.Uint32(attrs[j].Value[0:4])
if i != 0xffffffff {
rule.SuppressPrefixlen = int(i)
}
case nl.FRA_SUPPRESS_IFGROUP:
i := native.Uint32(attrs[j].Value[0:4])
if i != 0xffffffff {
rule.SuppressIfgroup = int(i)
}
case nl.FRA_FLOW:
rule.Flow = int(native.Uint32(attrs[j].Value[0:4]))
case nl.FRA_GOTO:
rule.Goto = int(native.Uint32(attrs[j].Value[0:4]))
case nl.FRA_PRIORITY:
rule.Priority = int(native.Uint32(attrs[j].Value[0:4]))
}
}
res = append(res, *rule)
}
return res, nil
}
|
