UDPTransport isn't sending traffic to remote_addr when local_addr is set

[vodik]

• uvloop version: 0.5.2
• python version: Python 3.5.2
• platform: Archlinux

Using the asyncio example udp echo server with uvloop. Works perfectly without uvloop, but once uvloop is used, the remote addr isn't set on the transport. Fails to send packets to the remote machine.

Note: It works if you run the server/client on the same machine. To replicate this, try going between two machines.

Inspecting the socket of the created transport, I see <socket.socket fd=10, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('0.0.0.0', 55216)>.

With asyncio, raddr is set (<socket.socket fd=6, family=AddressFamily.AF_INET, type=2050, proto=17, laddr=('10.200.0.9', 33074), raddr=('10.10.8.30', 9999)>).

I'd like to use this with aiosip, but I'm also seeing this problem there.

[vodik]

No, I had the server misconfigured. My bad. No bug.

[vodik]

No, false alarm again. I forgot to configure the client correct. One change must be made from the example. The client needs to set both a custom local_addr and remote_addr. Once you add it in, it routes traffic to the local_addr instead of the remote_addr.

[vodik]

Here's what I see in strace:

With local_addr set to 10.200.0.6:8000, the packet is sent from the local_addr and then recieve back again.

sendmsg(9, {msg_name={sa_family=AF_INET, sin_port=htons(8000), sin_addr=inet_addr("10.200.0.6")}, msg_namelen=16, msg_iov=[{iov_base="This is the message. It will be "..., iov_len=39}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 39
recvmsg(9, {msg_name={sa_family=AF_INET, sin_port=htons(8000), sin_addr=inet_addr("10.200.0.6")}, msg_namelen=128->16, msg_iov=[{iov_base="This is the message. It will be "..., iov_len=256000}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 39

Without the local_addr, for contrast, it sends and receives a packet from the remote_addr.

sendmsg(9, {msg_name={sa_family=AF_INET, sin_port=htons(9999), sin_addr=inet_addr("10.10.8.30")}, msg_namelen=16, msg_iov=[{iov_base="This is the message. It will be "..., iov_len=39}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 39
recvmsg(9, {msg_name={sa_family=AF_INET, sin_port=htons(9999), sin_addr=inet_addr("10.10.8.30")}, msg_namelen=128->16, msg_iov=[{iov_base="This is the message. It will be "..., iov_len=256000}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 39

Which explains why aiosip doesn't work. Both addresses are specified.

[vodik]

Think I found the bug. PR hopefully coming shortly.