Adding objects to LDAP via CGI

Question

I have a web form that collects information and submits it to a cgi that attempts to insert the data into LDAP. The problem is that I'm trying to use a variable with ::ldap::add and it's just not working. Here's the code:

if {[string length env(QUERY_STRING)] != 0} {
    set handle [::ldap::connect localhost]
    set dn "cn=admin,dc=mycompany,dc=com"
    set pw "myPassword"

    ::ldap::bind $handle $dn $pw

    set dn "cn=[ncgi::value givenName] [ncgi::value sn],ou=people,dc=mycompany,dc=com"

    set formValues [
            puts "cn        {{[ncgi::value givenName] [ncgi::value sn]}}"
            puts "displayName       [ncgi::value givenName] [ncgi::value sn]"
            foreach {key value} [ncgi::nvlist] {
                    if {[string length $value] != 0} {
                            puts "$key      $value"
                    }
            }
            puts "objectClass       top"
            puts "objectClass       person"
            puts "objectClass       organizationalPerson"
            puts "objectClass       inetOrgPerson"
    ]

    ::ldap::add $handle $dn {
            $formValues
    }

    ldap::unbind $handle

}

However, if I replace $formValues with the actual entries that I want to insert into LDAP, they get added just fine.

I'm new to TCL so I wouldn't be surprised if there were some glaring errors in this snippet.

Thanks in advance!

Answer 1

The big mistakes:

1. The square brackets substitute the result of the script inside it and not its output.
2. The puts commands sends strings to stdout (or a file) and doesn't save them for processing later.
3. The curly braces totally quash all substitutions inside them.

The fixes are to use list commands to build the description to use with ldap::add. For example:

set formValues {}
lappend formValues cn          "[ncgi::value givenName] [ncgi::value sn]"
### Might need this instead; it depends on how you want to do the construction
# lappend formValues cn        [list [ncgi::value givenName] [ncgi::value sn]]
lappend formValues displayName "[ncgi::value givenName] [ncgi::value sn]"
foreach {key value} [ncgi::nvlist] {
    ### Could also use {$value ne ""} here
    if {[string length $value] != 0} {
        lappend formValues $key $value
    }
}
lappend formValues objectClass top
lappend formValues objectClass person
lappend formValues objectClass organizationalPerson
lappend formValues objectClass inetOrgPerson

::ldap::add $handle $dn $formValues

Also, if those keys are coming from a form, you should add more validation to stop malicious users from adding unexpected extras like additional objectClasses. An ounce of prevention is worth a hundredweight of cure.