On 06/05/25 10:41 pm, Junio C Hamano wrote: > Aditya Garg <gargaditya08@xxxxxxxx> writes: > >> I think we can add a minimal check to ensure that there are no two dots together. >> Does that sound fair? > > Is it a common misconfiguration in the first place that singling out > a name ending with double dots (which indeed is very likely that > nobody should be relying on getting accepted by sensible SMTP > servers, hence very safe tightening) is worth doing? If MacBooks as > shipped would by default claim to be "MacBook.." like your example > had (I do not know if that is the case, as I do not live in Apple > ecosystem), it may give us a reason to special case the trailing > double-dots, for example. Its not an Apple thing. I am not even using macOS at the first place when I tested this, I was on Ubuntu running on my Mac. Its a problem with Net::Domain. In systems without a domainname, and without a period in the hostname, Net::Domain will always output "hostname..". You probably should check your machine with smtp-debug? Btw, the output of `hostname -f` on these machines will be "hostname". Now gmail does not reject this, probably the reason it is unnoticed? Since Outlook support is new, such problems are being observed. > > I personally feel that "run of at most 63 alnum or dash separated by > a single dot in between" is easy enough to explain, so if I were > doing this change, I would just use the regexp used in posted patch > [*] and if nobody complains, stop right there. If we get any > complaint, then I'd detect and reject the case where the string ends > with double-dots. The regexp used in the original patch covers the double dots case as well. Its basically following the RFC guidelines, which a sensible SMTP server should follow, and so must a user. > > [Footnote] > > * ... but I don't know if your use of negative lookaround > assersions is correct. Shouldn't the "a label cannot begin or > end with dash" be applied not just to the first label but > consistently to all of the dot-separated labels? I think you are talking about this case: someone.-example.com No, its not valid.a
