Please review (take 2): [Bug 199923] subtree search fails to find items under a db containing special characters

[Noriko Hosoi]

Subject: subtree search fails to find items under a db containing 
special characters

https://bugzilla.redhat.com/show_bug.cgi?id=199923

Files:
  ldap/servers/plugins/syntaxes/validate.c
  ldap/servers/slapd/back-ldbm/ldbm_add.c
  ldap/servers/slapd/dn.c

Fix Description:
dn.c: Based upon RFC 4514, the following characters in the RDN
values need to be escaped:
   '+', ';', '<','>', and '=' for the intermediate characters
   '+', ';', '<','>', '=', '#' and ' ' for leading characters
   '+', ';', '<','>', '=', and ' ' for trailing characters

validate.c: If an escaped character followed by another escaped
character, e.g., #<,  the pointer was moved twice skipping ''
before '<' and it makes the validation fail.

ldbm_add.c: a local variable addr was not initialized.

Thanks to Nathan for his review.  I revised dn.c based upon
his review comments.

Proposed Fix:
https://bugzilla.redhat.com/attachment.cgi?id=399189&action=diff
https://bugzilla.redhat.com/attachment.cgi?id=399189&action=edit