Jeff King <peff@xxxxxxxx> writes: >> > We seem to match url schemes case-sensitively: >> > >> > $ git clone SSH://example.com/repo.git >> > Cloning into 'repo'... >> > fatal: Unable to find remote helper for 'SSH' >> > >> > whereas rfc3986 is clear that the scheme portion is case-insensitive. >> > We probably ought to match at least our internal ones with strcasecmp. >> >> That may break if somebody at DevToolGroup@$BIGCOMPANY got cute and >> named their custom remote helper SSH:// that builds on top of the >> normal ssh:// protocol with something extra and gave it to their >> developers (and they named the http counterpart that has the same >> extra HTTP://, of course). > > True, though I am on the fence whether that is a property worth > maintaining. AFAIK it was not planned and is just a "this is how it > happened to work" case that is (IMHO) doing the wrong thing. FWIW, I fully agree with the assessment; sorry for not saying that together with the devil's advocate comment to save a round-tip. > It may also interact in a funny way with our allowed-protocol code, if > "SSH" gets a pass as "ssh" under the default config, but actually runs > the otherwise-disallowed git-remote-SSH (though one would _hope_ if you > have such a git-remote-SSH that it behaves just like an ssh remote). True. I did not offhand recall how protocol whitelist matches the protocol name with config, but transport.c::get_protocol_config() seems to say that the <name> part of "protocol.<name>.allow" is case sensitive, and we match known-safe (and known-unsafe "ext::") protocols with strcmp() not strcasecmp(). We need to figure out the implications of allowing SSH:// not to error out but pretending as if it were ssh:// on those who have protocol.ssh.allow defined. >> > We could probably also give an advise() message in the above output, >> > suggesting that the problem is likely one of: >> > >> > 1. They misspelled the scheme. >> > >> > 2. They need to install the appropriate helper. >> > >> > This may be a good topic for somebody looking for low-hanging fruit to >> > get involved in development (I'd maybe call it a #leftoverbits, but >> > since I didn't start on it, I'm not sure if it counts as "left over" ;)). >> [..] >> It may probably be a good idea to do an advice, but I'd think >> "Untable to find remote helper for 'SSH'" may be clear enough. If >> anything, perhaps saying "remote helper for 'SSH' protocol" would >> make it even clear? I dunno. > > I think it doesn't help much if the user does not know what a remote > helper is, or why Git is looking for one. True. $ git clone SSH://example.com/repo.git fatal: unable to handle URL that begins with SSH:// would be clear enough, perhaps? At least this line of change is a small first step that would improve the situation without potential to break anybody who has been abusing the case sensitivity loophole.
