Rafael Pfister

LDAP / Active Directory

Find users, test bind, Root DSE and LDAPS.

Find a user

Finds a user by sAMAccountName and shows core attributes (name, mail, DN, groups).

Active Directory

Username (sAMAccountName)
jdoe Change in the builder →

PowerShell (Windows)

DirectorySearcher (.NET) Built-in 

$s = New-Object DirectoryServices.DirectorySearcher
$s.SearchRoot = "LDAP://dc01.example.com/DC=example,DC=com"
$s.Filter = "(sAMAccountName=jdoe)"
"displayName", "mail", "distinguishedName", "memberOf" | ForEach-Object { [void]$s.PropertiesToLoad.Add($_) }
$r = $s.FindOne()
if ($r) { $r.Properties } else { "not found" }

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -b "DC=example,DC=com" "(sAMAccountName=jdoe)" displayName mail distinguishedName memberOf

Unix shell (bash)

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -b "DC=example,DC=com" "(sAMAccountName=jdoe)" displayName mail distinguishedName memberOf

curl Add-on tool 

curl -s "ldap://dc01.example.com/DC=example,DC=com?displayName,mail?sub?(sAMAccountName=jdoe)"

Without bind details the search runs as the signed-in Windows user (integrated auth). Linux has no built-in LDAP client: use ldapsearch (openldap-clients / ldap-utils) or curl with LDAP support; for ldapsearch add -D <bind DN> -W if needed.

Test bind / logon

Checks whether an account can bind (authenticate) to the directory.

PowerShell (Windows)

DirectoryEntry (.NET) Built-in 

$de = New-Object DirectoryServices.DirectoryEntry("LDAP://dc01.example.com", "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com", "P@ssw0rd")
try { $null = $de.NativeObject; "bind ok: $($de.distinguishedName)" }
catch { "bind failed: $($_.Exception.Message)" }

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -D "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com" -W -b "" -s base "(objectClass=*)" 1.1

Unix shell (bash)

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -D "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com" -W -b "" -s base "(objectClass=*)" 1.1

curl Add-on tool 

curl -s -u "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com:P@ssw0rd" "ldap://dc01.example.com/"

Replace P@ssw0rd with the real password. -W in ldapsearch prompts for the password interactively.

Custom filter

Runs an LDAP search with a free-form filter and lists the matching DNs.

PowerShell (Windows)

DirectorySearcher (.NET) Built-in 

$root = New-Object DirectoryServices.DirectoryEntry("LDAP://dc01.example.com/DC=example,DC=com", "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com", "P@ssw0rd")
$s = New-Object DirectoryServices.DirectorySearcher($root, "(&(objectClass=user)(sAMAccountName=jdoe))")
$s.PageSize = 200
$s.FindAll() | ForEach-Object { $_.Properties["distinguishedname"] }

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -D "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com" -W -b "DC=example,DC=com" "(&(objectClass=user)(sAMAccountName=jdoe))" dn

Unix shell (bash)

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -D "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com" -W -b "DC=example,DC=com" "(&(objectClass=user)(sAMAccountName=jdoe))" dn

curl Add-on tool 

curl -s -u "CN=svc-ldap,OU=Service Accounts,DC=example,DC=com:P@ssw0rd" "ldap://dc01.example.com/DC=example,DC=com?dn?sub?(&(objectClass=user)(sAMAccountName=jdoe))"

Replace P@ssw0rd with the real password. For an anonymous search, drop the bind part.

Root DSE

Reads the Root DSE: naming contexts, hostname and supported LDAP version, without authenticating.

PowerShell (Windows)

[ADSI] RootDSE Built-in 

$r = [ADSI]"LDAP://dc01.example.com/RootDSE"
$r.defaultNamingContext; $r.dnsHostName; $r.supportedLDAPVersion; $r.rootDomainNamingContext

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -s base -b "" "(objectClass=*)" +

Unix shell (bash)

ldapsearch Add-on tool 

ldapsearch -x -H ldap://dc01.example.com -s base -b "" "(objectClass=*)" +

curl Add-on tool 

curl -s "ldap://dc01.example.com/?+?base?(objectClass=*)"

LDAPS (636)

Checks the encrypted LDAP connection and shows its certificate.

LDAPS (636)

PowerShell (Windows)

SslStream (.NET) Built-in 

$h = "dc01.example.com"; $p = 636
$c = New-Object Net.Sockets.TcpClient($h, $p)
$ssl = New-Object Net.Security.SslStream($c.GetStream(), $false, ({ $true }))
$ssl.AuthenticateAsClient($h)
([Security.Cryptography.X509Certificates.X509Certificate2]$ssl.RemoteCertificate) | Format-List Subject, Issuer, NotAfter
$ssl.Dispose(); $c.Close()

ldapsearch Add-on tool 

ldapsearch -x -H ldaps://dc01.example.com:636 -s base -b "" "(objectClass=*)" 1.1

Unix shell (bash)

openssl Built-in 

openssl s_client -connect dc01.example.com:636 </dev/null 2>/dev/null | openssl x509 -noout -subject -dates

ldapsearch Add-on tool 

LDAPTLS_REQCERT=allow ldapsearch -x -H ldaps://dc01.example.com:636 -s base -b "" "(objectClass=*)" 1.1

Globaler Katalog (3269)

PowerShell (Windows)

SslStream (.NET) Built-in 

$h = "dc01.example.com"; $p = 3269
$c = New-Object Net.Sockets.TcpClient($h, $p)
$ssl = New-Object Net.Security.SslStream($c.GetStream(), $false, ({ $true }))
$ssl.AuthenticateAsClient($h)
([Security.Cryptography.X509Certificates.X509Certificate2]$ssl.RemoteCertificate) | Format-List Subject, Issuer, NotAfter
$ssl.Dispose(); $c.Close()

ldapsearch Add-on tool 

ldapsearch -x -H ldaps://dc01.example.com:3269 -s base -b "" "(objectClass=*)" 1.1

Unix shell (bash)

openssl Built-in 

openssl s_client -connect dc01.example.com:3269 </dev/null 2>/dev/null | openssl x509 -noout -subject -dates

ldapsearch Add-on tool 

LDAPTLS_REQCERT=allow ldapsearch -x -H ldaps://dc01.example.com:3269 -s base -b "" "(objectClass=*)" 1.1

LDAPTLS_REQCERT=allow accepts an untrusted certificate too, so the test connection succeeds.

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