lib: Add restrict_access_flags enum to use with restrict_access[_by_env]() Swap parameter locations in the functions to make sure plugins are updated to use the new api.

lib: Flip drop_setuid_root in restrict_access_settings

lib: Add restrict_access_get/set_dumpable

lib: Clarify restrict_access_allow_coredumps

lib: Add drop_setuid_root for restrict_access drop_setuid_root, when set to true, will detect and try to drop getuid()==0. This is done by recovering current effective UID to set->uid if set->uid == -1, and then doing seteuid(0). It will also drop out any other extra privileges, such as extra groups not requested for.

Marked functions parameters that are allowed to be NULL. Some APIs were also changed. The non-obvious APIs where NULL parameter was changed to "" are master_service_init() and auth_master_user_list_init(). These checks can currently be enabled only on a patched clang: http://llvm.org/bugs/show_bug.cgi?id=6786

restrict_access(): Show uid/gid source in setuid()/setgid() failure messages if given.

Added restrict_access_get_env() --HG-- branch : HEAD

Added restrict_get_groups_list() for easily getting list of process's groups. --HG-- branch : HEAD

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

restrict-access: More fixes to root checking. --HG-- branch : HEAD

Cleaned up restrict_access*() API. --HG-- branch : HEAD

Improved logging for core dumping. With Linux use PR_SET_DUMPABLE for imap/pop3. --HG-- branch : HEAD

Improved logging for core dumping. With Linux use PR_SET_DUMPABLE for imap/pop3. --HG-- branch : HEAD

Replaced mail_extra_groups setting with mail_privileged_group and mail_access_groups settings. mail_privileged_group allows temporary access to the group when creating mbox INBOX dotlocks. --HG-- branch : HEAD

Replaced mail_extra_groups setting with mail_privileged_group and mail_access_groups settings. mail_privileged_group allows temporary access to the group when creating mbox INBOX dotlocks. --HG-- branch : HEAD

Reverted "environment array" changes. It broke overriding imap/pop3 settings from userdb and the performance improvements weren't all that great anyway. --HG-- branch : HEAD

Build environment using envarr and pass it to execve(). This is faster than using putenv() directly. restrict_access_*_env() API changed to take environment array parameter. --HG-- branch : HEAD

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

Added "bool" type and changed all ints that were used as booleans to bool. --HG-- branch : HEAD

Added mail_extra_groups setting. --HG-- branch : HEAD

Allow first_valid_gid to be 0. Drop any supplementary groups not in valid gid range. --HG-- branch : HEAD

Removed restrict_access_clean_env() and env_remove(). They're not needed. --HG-- branch : HEAD

Added env_remove() and restrict_access_clear_env(). --HG-- branch : HEAD

Drop root privileges earlier. Close syslog more later in imap-master when forking new processes, so that any errors get logged. Make sure that all errors show up in log files - use specific exit status codes if we can't write to log file. Make sure imap and login processes always drop root privileges even if master process didn't ask for it for some reason. putenv() wasn't verified to succeed - luckily we never allowed large user given data there. --HG-- branch : HEAD

Initial revision --HG-- branch : HEAD