auth: client protocol: Record minor version for authentication client connection.

global: unsigned int:1 -> bool:1 perl -i -pe 's/unsigned int ([^,:;]+):1;/bool $1:1;/' **/*.[ch]

Added support to perform token-based service process authentication. Creates hidden SASL method DOVECOT-TOKEN. This method is not available on the normal auth login socket and thus never presented to clients. Creates new auth socket type 'tokenlogin'. This otherwise normal login socket only offers authentication using the DOVECOT-TOKEN mechanism. Creates new token-login directory in base_dir to separate token logins from normal logins. This directory is otherwise completely identical to the normal login dir, i.e. it contains sockets for the service backends, used to chroot login processes to, etc. Makes default login socket configurable. Performs some minor changes to src/login-common to build very sparse protocols, e.g. avoid the need to implement methods that are not needed.

Added o_stream_nsend*() and related functions to make delayed error handling safer. Once o_stream_nsend*() is called, o_stream_nfinish() must be called before stream is destroyed to finish checking if there were any errors. If something failed and the stream is just wanted to be closed, o_stream_ignore_last_errors() can be called. For streams where errors don't really make any difference (network sockets) you can call o_stream_set_no_error_handling() immediately after creating the stream.

auth: Use linked list instead of array for storing list of auth connections. With arrays the removal was slower than necessary.

auth: Separate auth and login connections. Non-login requests are freed immediately after auth finished. The login connections are used by Dovecot internally, while the auth connections are for SMTP AUTH etc. --HG-- branch : HEAD

Redesigned how login process passes connections to mail processes and changed related APIs. Master process is no longer in the middle. --HG-- branch : HEAD

auth: Identify clients using a 128bit random cookie on top of the existing PID. When master is finishing the login, it must give this cookie to REQUEST command and it must match what auth process knows. This change makes it safe to do client/master login without a dedicated master process. --HG-- branch : HEAD

Initial commit for v2.0 master rewrite. Several features are still missing. --HG-- branch : HEAD

Changed .h ifdef/defines to use <NAME>_H format. --HG-- branch : HEAD

deinit, unref, destroy, close, free, etc. functions now take a pointer to their data pointer, and set it to NULL. This makes double-frees less likely to cause security holes. --HG-- branch : HEAD

Allow multiple master connections for a single listener. --HG-- branch : HEAD

Moving code around. --HG-- branch : HEAD

Removed SERVICE command. It's quite useless extra state to keep around. --HG-- branch : HEAD

Reorganized the code to have less global/static variables. --HG-- branch : HEAD

s/protocol/service/ in authentication --HG-- branch : HEAD

If auth client sends broken input and we disconnect it, wait for a while before disconnecting to avoid flooding. --HG-- branch : HEAD

Added VERSION command and checking to authentication protocol. --HG-- branch : HEAD

Changed dovecot-auth protocol to ASCII based. Should be easier now to write replacement server if needed by someone. Also cleaned up/made more consistent auth code. The new code could still use some cleaning though.. --HG-- branch : HEAD

Added APOP authentication for POP3. Patch by Andrey Panin. This required some changes in auth APIs. --HG-- branch : HEAD

Moved client side code for auth process handling to lib-auth. Some other login process cleanups. --HG-- branch : HEAD