jcoffey-dev
fb785b8635
A school, or any organization that doesn't want people's mailboxes shared, can now turn that off (multi-account spec, MA-C). Two switches at two levels, as the legacy-protocols switch has: - mailSharing: people may share their own mail folders; - addAccounts: people may add other accounts to the webmail (read by the webmail's account switcher, MA-B). inbuxa:SharingPolicy/get and /set hold them: the server's policy has the singleton id, each tenant's has the tenant's id. Both default to on, so nothing changes until someone turns one off. A tenant's administrator changes their own tenant's (the domain's permissions, as for its protocols switch); only a server administrator with sysSharingUpdate changes the server's; a tenant can never be looser than the server (forbidden). Every change goes through the audit log, and rebuilds every access token, here and on every node. With mail sharing off for an account's tenant (or the server): - Mailbox/set and IMAP SETACL refuse to start or widen a share (forbidden / NO [NOPERM]); narrowing or ending one is always allowed; - shares already made give nothing while it is off: an access token leaves out mailbox grants from such an owner. They stay stored, so turning sharing back on restores them (John, 2026-10-05); - a lock's and a shared mailbox's grants are an administrator's and always count, and group membership was never a share. The session's own account says mailSharing and addAccounts, the stricter of the two levels, so front ends can hide what is off. Tests: a new sharing_policy suite with a school tenant, its own administrator and two people outside it: on by default; the school's administrator turns it off but can't touch the server's; an old share stops working and a new one is refused while someone outside the school is unaffected; a shared mailbox in the school keeps working; the server off can't be loosened by the tenant; on again restores the old share; ending a share works while off; and every change is audited. A unit test covers the stricter-only rule. sharing_policy_tests, jmap_tests, imap_tests, account_lock_tests and audit_log_tests pass (RocksDB).