For my friends and enemies. – 比特客栈的文艺复兴

Afterthought:

This is NOT a secure solution, although Mallory is not currently equipped to handle response from Charlie, it certainly can be adapted to do so (eg. filter incoming traffic, script injection).
I am almost certain Bob cannot trick Charlie into establishing a HTTPS connection with Alice, but I could be wrong, as one of the pre-condition for securing connection is for Alice to NOT give the key to a third-party, which we will in this case.
As a temp solution this should work seamlessly with West Chamber (which filters fake responses so Alice can maintain the connection), the difference between server Bob and Web Proxy/VPN/SSH tunnel/whatnot is that data from Charlie goes directly to Alice, so Bob’s bandwidth/CPU cost can be kept to minimal.
As mentioned in the diagram, each Bob should only handle a limited amount of users, otherwise it will be flagged as DoS. On the plus side, since no service other than authentication or request forging is offered by Bob, it has limited exposure, making it harder to identify.
If you think about it, this is effectively “a MITM solution to a MITM attack” :-) Just to keep the cat-n-mouse game exciting.

UPDATE: anchors added to image.

UPDATE2: what Mallory does is “ICMP DoS attack” (not to be confused with “ICMP flood”), once West Chamber can handle forged CM(control message), this MITM plan will be achievable.