Tunneling proxies via ssh - Raspberry Pi Forums

i want connect rpi internet through ssh proxy server, i'm struggling little.

here scenario. have 3 machines, let's call them a, vm & rpi.
remote linux machine on internet can freely access internet.
vm virtual ubuntu machine on pc cannot access internet except connecting machine via ssh.
rpi cannot access internet or machine a, directly connected pc vm running on.
vm can access rpi via ssh, rpi cannot access vm due firewall.

want allow rpi access internet via a.

far have been able establish proxy server via ssh using:
vm# ssh -d 1080 a_user@a_ip
can set http_proxy on vm socks5:a_ip:1080 , vm can access internet via proxy server on a.

have connected rpi vm using reverse tunnel.
vm# ssh -fn -r 7000:localhost:22 rpi_user@rpi_ip
rpi# ssh vm_user@localhost -p 7000

how can join these 2 connections @ vm allow rpi use proxy server on a?

have create proxy server on vm too?
or tunnel port 1080 rpi vm?
have read need enable gateway_proxies in ssh allow external clients use same proxy tunnel, i'm not sure if or should set.

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