Fix downlink GTP packets not being forwarded when ue_addr_ipv4 is set
#138
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louisroyer
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Please merge free5gc/gtp5g#138 first.
louisroyer
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Please merge free5gc/gtp5g#138 first.
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For free5GC's UPF's compatibility, apply free5gc/gtp5g#138
louisroyer
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Please merge free5gc/gtp5g#138 first.
louisroyer
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Please merge free5gc/gtp5g#138 first.
louisroyer
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Please merge free5gc/gtp5g#138 first.
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Please merge free5gc/gtp5g#138 first.
According to TS 129.244 Table 7.5.2.2-2: PDI IE within PFCP Session Establishment Request: > UE IP address: If present, this IE shall identify the UE IP address > as the source **or destination IP address** to match for the incoming packet. When `gtp.role == GTP5G_ROLE_UPF`, only the source address was checked. This resulted in dropping downlink GTP packets when UE IP address IE was set. This bug makes freeGC's go-upf incompatible with some third party SMFs. To reproduce the bug: 1. setup a free5GC network with an UPF-I and an UPF-A. 2. start pinging the Data Network from the UE 3. use `gtp5g-tunnel` to edit the downlink pdr by adding the UE IP address on the downlink PDR. 4. Without this PR, ICMP responses are no longer received from the UE because the UPF-i is dropping related GTP packets. When merged, this will allow https://github.com/free5gc/smf/blob/d049a7aa51db56cb2fad33713e422deac77ee2eb/internal/context/datapath.go#L636-L640 to be uncommented on free5GC's SMF. This also probably resolves the related FR5GC-1029 issue (but I don't have access to issue details, so I'm not sure).
tim-ywliu
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Please merge free5gc/gtp5g#138 first.
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According to TS 129.244 Table 7.5.2.2-2: PDI IE within PFCP Session Establishment Request:
When
gtp.role == GTP5G_ROLE_UPF, only the source address was checked. This resulted in dropping downlink GTP packets when UE IP address IE was set.This bug makes freeGC's go-upf incompatible with some third party SMFs.
To reproduce the bug:
gtp5g-tunnelto edit the downlink pdr by adding the UE IP address on the downlink PDR.When merged, this will allow
https://github.com/free5gc/smf/blob/d049a7aa51db56cb2fad33713e422deac77ee2eb/internal/context/datapath.go#L636-L640 to be uncommented on free5GC's SMF. This also probably resolves the related FR5GC-1029 issue (but I don't have access to issue details, so I'm not sure).