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dbardbardbardbar
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Handle sflow packet with gaps between samples
1 parent 9ae42e9 commit c1c609a

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2 files changed

+127
-0
lines changed

2 files changed

+127
-0
lines changed

‎sflow/decoder.go

+24
Original file line numberDiff line numberDiff line change
@@ -81,6 +81,7 @@ var (
8181
errNoneEnterpriseStandard = errors.New("the enterprise is not standard sflow data")
8282
errDataLengthUnknown = errors.New("the sflow data length is unknown")
8383
errSFVersionNotSupport = errors.New("the sflow version doesn't support")
84+
errSampleLengthInvalid = errors.New("the sflow sample length is invalid")
8485
)
8586

8687
// NewSFDecoder constructs new sflow decoder
@@ -112,6 +113,8 @@ func (d *SFDecoder) SFDecode() (*SFDatagram, error) {
112113
continue
113114
}
114115

116+
var offsetBefore, _ = d.reader.Seek(0, 1)
117+
115118
switch sfTypeFormat {
116119
case DataFlowSample:
117120
d, err := decodeFlowSample(d.reader)
@@ -129,11 +132,32 @@ func (d *SFDecoder) SFDecode() (*SFDatagram, error) {
129132
d.reader.Seek(int64(sfDataLength), 1)
130133
}
131134

135+
err = d.sfMoveToEndOfSample(sfDataLength, offsetBefore)
136+
if err != nil {
137+
return datagram, err
138+
}
139+
132140
}
133141

134142
return datagram, nil
135143
}
136144

145+
func (d *SFDecoder) sfMoveToEndOfSample(sfDataLength uint32, offsetBefore int64) error {
146+
var offsetAfter, _ = d.reader.Seek(0, 1)
147+
var bytesRead = offsetAfter - offsetBefore
148+
var byteUntilEndOfSample = int64(sfDataLength) - bytesRead
149+
if byteUntilEndOfSample < 0 {
150+
return errSampleLengthInvalid
151+
}
152+
if byteUntilEndOfSample > 0 {
153+
var _, err = d.reader.Seek(byteUntilEndOfSample, 1)
154+
if err != nil {
155+
return err
156+
}
157+
}
158+
return nil
159+
}
160+
137161
func (d *SFDecoder) sfHeaderDecode() (*SFDatagram, error) {
138162
var (
139163
datagram = &SFDatagram{}

‎sflow/decoder_test.go

+103
Original file line numberDiff line numberDiff line change
@@ -102,6 +102,92 @@ var TestsFlowRawPacket = []byte{0x00, 0x00, 0x00, 0x05, 0x00, 0x00,
102102
0x00, 0x00, 0x00, 0x00, 0x03, 0xea, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x01, 0xce, 0x48,
103103
0xd3, 0x16, 0x00, 0x00, 0x00, 0x18, 0x00, 0x00, 0x00, 0x15}
104104

105+
var TestsFlowRawPacketWithPaddingAfterSample = []byte{
106+
0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00, 0x01, 0x0a, 0x00, 0x02, 0xf6, 0x00, 0x00, 0x00, 0x01,
107+
0x36, 0x2d, 0xc7, 0x73, 0x37, 0xc5, 0x77, 0xb4, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00, 0x01,
108+
0x00, 0x00, 0x00, 0xd0, 0x38, 0x78, 0x45, 0x37, 0x00, 0x00, 0x00, 0x82, 0x00, 0x00, 0x04, 0x00,
109+
0xb0, 0x47, 0x04, 0x70, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x82, 0x80, 0x00, 0x00, 0x00,
110+
0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x90, 0x00, 0x00, 0x00, 0x01,
111+
0x00, 0x00, 0x05, 0x56, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x80, 0x01, 0x00, 0x5e, 0x00,
112+
0x67, 0x20, 0x90, 0xe2, 0xba, 0x39, 0x8e, 0x27, 0x08, 0x00, 0x45, 0x00, 0x05, 0x40, 0x00, 0x00,
113+
0x40, 0x00, 0x1e, 0x11, 0x23, 0xd5, 0xc0, 0xa8, 0x2c, 0x0f, 0xe0, 0x00, 0x67, 0x20, 0xd3, 0xdb,
114+
0x07, 0xd1, 0x05, 0x2c, 0x84, 0x51, 0x47, 0x01, 0x9a, 0x17, 0xc1, 0xbd, 0x62, 0xd6, 0xaf, 0xb2,
115+
0x5c, 0x85, 0xf5, 0x03, 0x6b, 0x5b, 0x74, 0x66, 0x80, 0xe2, 0xa9, 0xb3, 0x21, 0x29, 0x64, 0x7c,
116+
0xe7, 0xb4, 0xe3, 0x6c, 0x82, 0xc1, 0xb3, 0xf7, 0x19, 0x32, 0xd1, 0xb2, 0x52, 0xb0, 0xc3, 0x92,
117+
0x90, 0x07, 0x21, 0xc6, 0x3d, 0x2c, 0x74, 0xe2, 0x26, 0x3a, 0x0e, 0x58, 0xc0, 0xaa, 0x16, 0xb4,
118+
0xf1, 0xc4, 0x3b, 0xbb, 0x4f, 0xfb, 0x9e, 0x09, 0x45, 0x64, 0x85, 0xdd, 0x1e, 0xfe, 0x42, 0x6a,
119+
0x57, 0x5e, 0xeb, 0x8b, 0x79, 0x92, 0xb6, 0x94, 0xbc, 0x05, 0x54, 0x83, 0x00, 0x00, 0x03, 0xe9,
120+
0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x01, 0xbc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xbc,
121+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x1c, 0x90, 0x4d, 0xe8, 0x35,
122+
0x00, 0x00, 0x00, 0x81, 0x00, 0x00, 0x04, 0x00, 0x76, 0xb3, 0xaa, 0xe0, 0x00, 0x00, 0x00, 0x00,
123+
0x00, 0x00, 0x00, 0x81, 0x00, 0x00, 0x00, 0x83, 0x00, 0x00, 0x00, 0x04, 0x00, 0x00, 0x00, 0x01,
124+
0x00, 0x00, 0x00, 0x90, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x05, 0xc0, 0x00, 0x00, 0x00, 0x08,
125+
0x00, 0x00, 0x00, 0x80, 0x60, 0x9c, 0x9f, 0x43, 0xf0, 0x62, 0xe0, 0xac, 0xf1, 0x1c, 0xcf, 0xed,
126+
0x08, 0x00, 0x45, 0x28, 0x05, 0xaa, 0x28, 0x4f, 0x40, 0x00, 0x58, 0x06, 0xd2, 0xed, 0x1f, 0x0d,
127+
0x42, 0x0e, 0x48, 0x09, 0x78, 0xc5, 0x01, 0xbb, 0xdd, 0x4a, 0xda, 0x0e, 0xe5, 0xe6, 0xea, 0x42,
128+
0x35, 0x2e, 0x80, 0x10, 0x00, 0xbd, 0xef, 0x4e, 0x00, 0x00, 0x01, 0x01, 0x08, 0x0a, 0xe7, 0x30,
129+
0x3a, 0xf9, 0x20, 0x01, 0xb3, 0x30, 0xa6, 0xc6, 0xe7, 0x9a, 0x61, 0x09, 0x3d, 0x2e, 0xb2, 0x8f,
130+
0x99, 0x0a, 0xeb, 0x4c, 0x61, 0x9a, 0xd0, 0xb9, 0x24, 0x8c, 0x29, 0x46, 0x4f, 0xcd, 0xc3, 0x9e,
131+
0x09, 0x6a, 0x33, 0x85, 0xba, 0xcb, 0x26, 0xdf, 0x14, 0x89, 0x97, 0x15, 0xc6, 0x82, 0xa7, 0x92,
132+
0x2c, 0x99, 0xdb, 0xfb, 0x17, 0xb3, 0x25, 0xa7, 0xdc, 0xf5, 0x8e, 0xfd, 0x39, 0x30, 0x3f, 0x7e,
133+
0x55, 0x36, 0x03, 0x4e, 0x00, 0x00, 0x03, 0xe9, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x69,
134+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0xd2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xea,
135+
0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
136+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xeb, 0x00, 0x00, 0x00, 0x28, 0x00, 0x00, 0x00, 0x01,
137+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7d, 0xa0, 0x00, 0x00, 0x00, 0xae, 0x00, 0x00, 0x00, 0xae,
138+
0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
139+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0xd0,
140+
0x1a, 0xf2, 0x91, 0x87, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x04, 0x00, 0x1a, 0x8c, 0xd9, 0xd0,
141+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02,
142+
0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x90, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x05, 0x56,
143+
0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x80, 0x01, 0x00, 0x5e, 0x01, 0x73, 0x24, 0x00, 0x21,
144+
0x9b, 0x97, 0xd7, 0xd3, 0x08, 0x00, 0x45, 0x00, 0x05, 0x40, 0xe6, 0xf2, 0x40, 0x00, 0x40, 0x11,
145+
0xee, 0x3f, 0x0a, 0x00, 0x02, 0x55, 0xe1, 0x01, 0x73, 0x24, 0xd8, 0x04, 0x07, 0xd1, 0x05, 0x2c,
146+
0xe7, 0xf8, 0x47, 0x00, 0x6e, 0x16, 0x4d, 0xa6, 0x49, 0x3e, 0x43, 0xff, 0xde, 0x92, 0x27, 0x88,
147+
0x98, 0x79, 0xe9, 0xfb, 0x9f, 0x6e, 0xc3, 0x84, 0x12, 0xd0, 0x4e, 0x18, 0x4b, 0x4e, 0xf2, 0xc5,
148+
0x0b, 0xfb, 0x85, 0xf4, 0x99, 0x15, 0x66, 0xe7, 0x36, 0x23, 0x6a, 0x7c, 0xe2, 0x3a, 0x13, 0x20,
149+
0x00, 0x2b, 0xc1, 0xde, 0x3b, 0xe0, 0xa4, 0x45, 0xdd, 0x4d, 0xc1, 0x87, 0x4f, 0x60, 0xae, 0x2f,
150+
0x87, 0x97, 0x35, 0x2c, 0x64, 0xa0, 0xe2, 0xd7, 0xb0, 0x1b, 0x30, 0xce, 0xaa, 0x37, 0xd4, 0x46,
151+
0xaa, 0x69, 0x27, 0x27, 0xb9, 0x3f, 0xb3, 0x82, 0x00, 0x00, 0x03, 0xe9, 0x00, 0x00, 0x00, 0x10,
152+
0x00, 0x00, 0x03, 0x90, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x90, 0x00, 0x00, 0x00, 0x00,
153+
0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x1c, 0x38, 0x78, 0x45, 0x38, 0x00, 0x00, 0x00, 0x82,
154+
0x00, 0x00, 0x04, 0x00, 0xb0, 0x47, 0x08, 0x70, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x82,
155+
0x00, 0x00, 0x00, 0x83, 0x00, 0x00, 0x00, 0x04, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x90,
156+
0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x05, 0xf2, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x80,
157+
0x60, 0x9c, 0x9f, 0x43, 0xf0, 0x62, 0x34, 0xdb, 0xfd, 0x04, 0x06, 0xc9, 0x08, 0x00, 0x45, 0x00,
158+
0x05, 0xdc, 0x00, 0x02, 0x40, 0x00, 0x3f, 0x06, 0xe1, 0x74, 0x6c, 0xaf, 0x27, 0xa2, 0x48, 0x09,
159+
0x78, 0x4b, 0x00, 0x50, 0xbf, 0x79, 0xb5, 0x97, 0x10, 0xc0, 0x25, 0x60, 0x3d, 0xfc, 0x80, 0x10,
160+
0x08, 0x02, 0x38, 0x51, 0x00, 0x00, 0x01, 0x01, 0x08, 0x0a, 0x48, 0xd0, 0xe9, 0x69, 0x00, 0x24,
161+
0x98, 0xe6, 0x6b, 0x08, 0x7f, 0xc6, 0x95, 0x2a, 0x22, 0x6a, 0xb6, 0x63, 0x81, 0x4c, 0x86, 0x5b,
162+
0xa3, 0xb8, 0xc0, 0x06, 0x4d, 0x17, 0x10, 0x7b, 0x92, 0x84, 0x58, 0x1b, 0x1f, 0xba, 0x67, 0x1f,
163+
0xe6, 0x5c, 0xce, 0xa7, 0x6f, 0xb0, 0x06, 0xc8, 0x33, 0xbb, 0x65, 0x6f, 0x2f, 0x4a, 0x24, 0x36,
164+
0xa2, 0xfe, 0xf8, 0xa8, 0x85, 0xc5, 0xf3, 0xfa, 0x78, 0xff, 0xe7, 0x04, 0x83, 0xf7, 0xe1, 0xf5,
165+
0x00, 0x00, 0x03, 0xe9, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x68, 0x00, 0x00, 0x00, 0x00,
166+
0x00, 0x00, 0x07, 0xd2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xea, 0x00, 0x00, 0x00, 0x10,
167+
0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
168+
0x00, 0x00, 0x03, 0xeb, 0x00, 0x00, 0x00, 0x28, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00,
169+
0x00, 0x00, 0x7d, 0xa0, 0x00, 0x00, 0x00, 0xae, 0x00, 0x00, 0x00, 0xae, 0x00, 0x00, 0x00, 0x01,
170+
0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
171+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x1c, 0x90, 0x4d, 0xe8, 0x36,
172+
0x00, 0x00, 0x00, 0x81, 0x00, 0x00, 0x04, 0x00, 0x76, 0xb3, 0xae, 0xe0, 0x00, 0x00, 0x00, 0x00,
173+
0x00, 0x00, 0x00, 0x81, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00, 0x04, 0x00, 0x00, 0x00, 0x01,
174+
0x00, 0x00, 0x00, 0x90, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x05, 0xf2, 0x00, 0x00, 0x00, 0x08,
175+
0x00, 0x00, 0x00, 0x80, 0x60, 0x9c, 0x9f, 0x43, 0xf0, 0x62, 0xe0, 0xac, 0xf1, 0x1c, 0xcf, 0xed,
176+
0x08, 0x00, 0x45, 0x48, 0x05, 0xdc, 0x97, 0xe0, 0x40, 0x00, 0x3c, 0x06, 0x53, 0x2d, 0x36, 0xc0,
177+
0x5b, 0x4d, 0x48, 0x09, 0x73, 0xb0, 0x01, 0xbb, 0xcb, 0xa1, 0xa4, 0x5b, 0x9c, 0x18, 0x23, 0x60,
178+
0x11, 0x4f, 0x80, 0x10, 0x00, 0x41, 0x2b, 0x11, 0x00, 0x00, 0x01, 0x01, 0x08, 0x0a, 0x3c, 0xdd,
179+
0x89, 0x41, 0x12, 0x81, 0xa7, 0xb8, 0xbe, 0xd7, 0x0d, 0x7b, 0xc6, 0x75, 0xe1, 0xf2, 0x03, 0x93,
180+
0xe3, 0x08, 0x17, 0xed, 0x4c, 0xda, 0x22, 0xef, 0xc1, 0xc3, 0x3d, 0x4e, 0x82, 0x11, 0xa0, 0xb5,
181+
0x93, 0x0d, 0x61, 0x06, 0xef, 0xd0, 0x83, 0x0c, 0xaa, 0x70, 0x79, 0x0a, 0x8f, 0x52, 0x5b, 0x7c,
182+
0x90, 0x0d, 0x19, 0x8b, 0x5f, 0xb5, 0x99, 0x73, 0x77, 0x60, 0x2c, 0x80, 0x28, 0x86, 0x64, 0xab,
183+
0xd6, 0xcd, 0xf5, 0xe6, 0x00, 0x00, 0x03, 0xe9, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x69,
184+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xea,
185+
0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x01, 0x0a, 0x00, 0x03, 0xfe, 0x00, 0x00, 0x00, 0x00,
186+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xeb, 0x00, 0x00, 0x00, 0x28, 0x00, 0x00, 0x00, 0x01,
187+
0x0a, 0x00, 0x03, 0xfe, 0x00, 0x00, 0x7d, 0xa0, 0x00, 0x00, 0x00, 0xae, 0x00, 0x00, 0x00, 0xae,
188+
0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
189+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}
190+
105191
func TestSFHeaderDecode(t *testing.T) {
106192
filter := []uint32{DataCounterSample}
107193
reader := bytes.NewReader(TestsFlowRawPacket)
@@ -180,6 +266,23 @@ func TestSFDecode(t *testing.T) {
180266
}
181267
}
182268

269+
func TestSFDecodeWithPaddingAfterSample(t *testing.T) {
270+
filter := []uint32{DataCounterSample}
271+
reader := bytes.NewReader(TestsFlowRawPacketWithPaddingAfterSample)
272+
d := NewSFDecoder(reader, filter)
273+
datagram, err := d.SFDecode()
274+
if err != nil {
275+
t.Error("unexpected error", err)
276+
}
277+
if len(datagram.Samples) != 5 {
278+
t.Error("expected samples## 5, got", len(datagram.Samples))
279+
}
280+
sample := datagram.Samples[4].(*FlowSample)
281+
if sample.RecordsNo != 4 {
282+
t.Error("expected RecordsNo 4, got ", sample.RecordsNo)
283+
}
284+
}
285+
183286
func TestDecodeSampleHeader(t *testing.T) {
184287
filter := []uint32{DataCounterSample}
185288
reader := bytes.NewReader(TestsFlowRawPacket)

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