Terence EdenI'm guessing the 64 character limit is poor database design. But is ".." valid within the local part of an email address?
Bob Young@Edent@mastodon.social
Your question sent me on a quest through RFC 5321, and I still don't know the answer. I'm guessing that more than one dot in a row isn't valid, but I've been wrong before.
Bob Young@Edent@mastodon.social
The 64 octet limit is legit, though.
RFC 5321
"The local-part of a mailbox MUST BE treated as case sensitive. Therefore, SMTP implementations MUST take care to preserve the case of mailbox local-parts. In particular, for some hosts, the user "smith" is different from the user "Smith". However, exploiting thecase sensitivity of mailbox local-parts impedes interoperability and is discouraged."
"Local-part = Dot-string / Quoted-string; MAY be case-sensitive"
"While the above definition for Local-part is relatively permissive, for maximum interoperability, a host that expects to receive mail SHOULD avoid defining mailboxes where the Local-part requires (or uses) the Quoted-string form or where the Local-part is case-sensitive."
"4.5.3.1.1.
Local-part The maximum total length of a user name or other local-part is 64 octets."
Terence Eden@fifonetworks@infosec.exchange that's of the local part, though.
Domains can be up to 253 ASCII characters long.
Bob Young@Edent@mastodon.social
Oh wow, I didn't catch that in the picture. Is it maybe just poor wording? If they're restricting the entire address to 64 bytes, that's really odd.