pgsql: Add a hook for modifying the ldapbind password

Add a hook for modifying the ldapbind password

The hook can be installed by a shared_preload library.

A similar mechanism could be used for radius paswords, for example, and
the type name auth_password_hook_typ has been shosen with that in mind.

John Naylor and Andrew Dunstan

Discussion: /messages/by-id/469b06ed-69de-ba59-c13a-91d2372e52a9@dunslane.net

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/419a8dd8142afef790dafd91ba39afac2ca48aaf

Modified Files
--------------
src/backend/libpq/auth.c | 12 ++-
src/include/libpq/auth.h | 6 ++
src/test/modules/Makefile | 11 +++
src/test/modules/ldap_password_func/Makefile | 25 +++++
.../ldap_password_func/ldap_password_func.c | 65 +++++++++++++
src/test/modules/ldap_password_func/meson.build | 33 +++++++
.../ldap_password_func/t/001_mutated_bindpasswd.pl | 103 +++++++++++++++++++++
src/test/modules/meson.build | 1 +
8 files changed, 255 insertions(+), 1 deletion(-)