svn commit: r1467563 - /directory/site/trunk/content/apacheds/advanced-ug/4.3-password-policy.mdtext

[el...@apache.org]

Author: elecharny
Date: Sat Apr 13 06:54:21 2013
New Revision: 1467563

URL: http://svn.apache.org/r1467563
Log:
More doco on PP

Modified:
    directory/site/trunk/content/apacheds/advanced-ug/4.3-password-policy.mdtext

Modified: directory/site/trunk/content/apacheds/advanced-ug/4.3-password-policy.mdtext
URL: http://svn.apache.org/viewvc/directory/site/trunk/content/apacheds/advanced-ug/4.3-password-policy.mdtext?rev=1467563&r1=1467562&r2=1467563&view=diff
==============================================================================
--- directory/site/trunk/content/apacheds/advanced-ug/4.3-password-policy.mdtext (original)
+++ directory/site/trunk/content/apacheds/advanced-ug/4.3-password-policy.mdtext Sat Apr 13 06:54:21 2013
@@ -24,9 +24,18 @@ Notice: Licensed to the Apache Software 
 
 # 4.3. Password Policy
 
-The **Password Policy** is a **RFC** draft that has been designed for the very first version in 1999, and the latest version is from 2009. Although it's still a draft, and it's currently noted as inactive, it has been implemented by many existing **LDAP** servers.
+The **Password Policy** is a **[RFC](http://tools.ietf.org/html/draft-behera-ldap-password-policy-10)** draft that has been designed for the very first version in 1999, and the latest version is from 2009. Although it's still a draft, and it's currently noted as inactive, it has been implemented by many existing **LDAP** servers.
+
+**ApacheDS** implements the draft.
+
+<DIV class="warn" markdown="1">
+Enforcing a strict passowrd policy is extremely punitive to users. It may leads users to workaround the policy by storing their password in a postit, an workaround that will defeat any password policy...
+
+Always try to think about better alternatives than force users to always define password with 10 or more characters, including numbers, upper and lower case, special chars, and to change it every month...
+
+A long sentence (4 or 5 words), like "The horse has won the race three time" is most certainly a better passowrd than any other combinaison, and is easy to remember...
+</DIV>
 
-**ApacheDS** implements the draft fully.
 
 ## What is a password policy ?
 
@@ -52,40 +61,68 @@ There is an entry contianing all the def
 
 This entry contains the following values :
 
+| Attrinbte | Default value | Comment |
+|---|---|---|
+| ads-pwdAllowUserChange | TRUE | tells if the user can change its password |
+| ads-pwdCheckQuality | 1 | The kind of quality we wnt for the password (0, 1, or 2) |
+| ads-pwdExpireWarning | 600 |  |
+| ads-pwdFailureCountInterval | 30 | The duration of failure logs we keep in the entry |
+| ads-pwdGraceAuthnLimit | 5 |  |
+| ads-pwdGraceExpire | 0 |  |
+| ads-pwdInHistory | 5 | The number of passwords we keep in the password history |
+| ads-pwdLockout | TRUE | Tells if the password should be locked or not on failures |
+| ads-pwdLockoutDuration | 0 | The delay we wait before allowing a new attept when the password hs been locked |
+| ads-pwdMaxAge | 0 |  |
+| ads-pwdMaxDelay | 0 | The maximum we wait before sending the BindResponse |
+| ads-pwdMaxFailure | 5 | The maximum number of failure we accept before locking the password |
+| ads-pwdMaxIdle | 0 |  |
+| ads-pwdMaxLength | 0 |  |
+| ads-pwdMinAge | 0 | The delay between two password changes |
+| ads-pwdMinDelay | 0 | The minimum we wait before sending the BindResponse |
+| ads-pwdMinLength | 5 |  |
+| ads-pwdMustChange | FALSE |  |
+| ads-pwdSafeModify | FALSE |  |
+
+Here is the entry :
+
 	:::Text
 	dn: ads-pwdId=default,ou=passwordPolicies,ads-interceptorId=authenticationIn
 	 terceptor,ou=interceptors,ads-directoryServiceId=default,ou=config
 	objectclass: top
 	objectclass: ads-base
 	objectclass: ads-passwordPolicy
-	ads-pwdattribute: userPassword
-	ads-pwdid: default
+	ads-pwdAttribute: userPassword
+	ads-pwdId: default
 	ads-enabled: TRUE
-	ads-pwdallowuserchange: TRUE
-	ads-pwdcheckquality: 1
-	ads-pwdexpirewarning: 600
-	ads-pwdfailurecountinterval: 30
-	ads-pwdgraceauthnlimit: 5
-	ads-pwdgraceexpire: 0
-	ads-pwdinhistory: 5
-	ads-pwdlockout: TRUE
-	ads-pwdlockoutduration: 0
-	ads-pwdmaxage: 0
-	ads-pwdmaxdelay: 0
-	ads-pwdmaxfailure: 5
-	ads-pwdmaxidle: 0
-	ads-pwdmaxlength: 0
-	ads-pwdminage: 0
-	ads-pwdmindelay: 0
-	ads-pwdminlength: 5
-	ads-pwdmustchange: FALSE
-	ads-pwdsafemodify: FALSE
+	ads-pwdAllowUserChange: TRUE
+	ads-pwdCheckQuality: 1
+	ads-pwdExpireWarning: 600
+	ads-pwdFailureCountInterval: 30
+	ads-pwdGraceAuthnLimit: 5
+	ads-pwdGraceExpire: 0
+	ads-pwdInHistory: 5
+	ads-pwdLockout: TRUE
+	ads-pwdLockoutDuration: 0
+	ads-pwdMaxAge: 0
+	ads-pwdMaxDelay: 0
+	ads-pwdMaxFailure: 5
+	ads-pwdMaxIdle: 0
+	ads-pwdMaxLength: 0
+	ads-pwdMinAge: 0
+	ads-pwdMinDelay: 0
+	ads-pwdMinLength: 5
+	ads-pwdMustChange: FALSE
+	ads-pwdSafeModify: FALSE
 
 
-#### Disabling the PasswordPolicy
+#### Enabling/Disabling the PasswordPolicy
 
 The _PasswordPolicy_ is enabled by default. It's possible to disable it by setting the _ads-enabled_ value to FALSE, with a server restart.
 
+## Usage
+
+We will explain in the following paragraphs how to configure the _PasswordPolicy_ and the impact each configuration has on the authentication.
+
 ### Password guessing limit
 
 The idea is to protect the password against multiple guess attempts. The following rules are applied :
@@ -99,10 +136,10 @@ When the account is locked, it can remai
 #### Attempts counter
 
 <DIV class="info" markdown="1">
-Attributes : ads-pwdLockout, ads-pwdmaxfailure
+Impacted Attributes : ads-pwdLockout, ads-pwdMaxFailure, ads-pwdLockoutDuration
 </DIV>
 
-Each failed attempt will be logged in the entry, in the _pwdFailureTime_ Attribute (it will contain the date of the attempt). When the Attribute contains more values than the maximum number of failed attempts, the entry will be locked (the _pwdAccountLockedTime_ Attribute will contain the date the entry has been locked).
+Each failed attempt will be logged in the entry, in the _ads-pwdFailureTime_ Attribute (it will contain the date of the attempt). When the Attribute contains more values than the maximum number of failed attempts, the entry will be locked (the _ads-pwdAccountLockedTime_ Attribute will contain the date the entry has been locked).
 
 <DIV class="warn" markdown="1">
 In order to activate this control the ads-pwdLockout parameter must be set to TRUE.
@@ -110,7 +147,7 @@ In order to activate this control the ad
 
 The following table expose the various possible cases, with three failed attempts : 
 
-| _ads-pwdmaxfailure_ | _pwdLockout_ | _pwdFailureTime_ | _pwdAccountLockedTime_ | Locked | Comment |
+| _ads-pwdmaxfailure_ | _ads-pwdLockout_ | _ads-pwdFailureTime_ | _ads-pwdAccountLockedTime_ | Locked | Comment |
 |---|---|---|---|---|---|
 | 3 | true | date1 | - | No | Failure 1 |
 |  |  | date1, date2 | - | No | Failure 2 |
@@ -119,5 +156,59 @@ The following table expose the various p
 |  |  | date1, date2 | - | No | Failure 2 |
 |  |  | date1, date2, date3 | - | No | Failure 3 |
 
-As we can see, the account is locked only when we reach the number of failure, and the _pwdLockout_ flag is TRUE.
+As we can see, the account is locked only when we reach the number of failure, and the _ads-pwdLockout_ flag is TRUE. If the _ads-pwdLockoutDuration_ flag is set, then the password will remain locked for the delay stored in this attribute.
+
+#### Delayed login
+
+<DIV class="info" markdown="1">
+Impacted Attributes : ads-pwdLockout, ads-pwdMaxFailure, ads-pwdLockoutDuration
+</DIV>
+
+When we have reached a number of failed attempt, the account will be locked. We can set another attribute to tell the server that the locked out account can be unlocked afer a delay : the _ads-pwdLockoutDuration_ Attribute stores this delay.
+
+When the account is locked, no further attempt will succed, even if the correct password is sent. After the delay, the user will be unlocked.
+
+#### Purging failures
+
+<DIV class="info" markdown="1">
+Impacted Attributes : ads-pwdFailureCountInterval
+</DIV>
+
+As we store all the failures withing the entry, at some point we may want to purge those failures. This is done either because we have successfully loged, or because the _ads-pwdFailureCountInterval_ value has expired. In this last case, all the failure older than the current time minus the set interval will be removed.
+
+
+### Password checks
+
+Those rules are used to enforce some constraints on the password, so that weak passwords can't be used.
+
+#### Password History
+
+<DIV class="info" markdown="1">
+Impacted Attributes : ads-pwdInHistory
+</DIV>
+
+The server can keep a backlog of passwords, so that a user can't keep a assword for ever. When requested to do so the user will have to change his/her password, and the old password will be stored in the user's entry password history.
+
+We can specify the number of passwords we keep in the password history by configuring the _ads-pwdInHistory_ attribute.
+
+#### Minimum delay between modifications
+
+<DIV class="info" markdown="1">
+Impacted Attributes : ads-pwdMinAge
+</DIV>
+
+When the password history is activated, some users may change their passwords many times to get their old password out of the history, and add it as their password again.  Setting a delay between two password changes may protect the password against such action.
+
+The _ads-pwdMinAge_ attribute is used for this purpose, and it keeps a value in seconds.
+
+#### Password length constraint
+
+<DIV class="info" markdown="1">
+Impacted Attributes : ads-pwdMinLength and ads-pwdMaxLength
+</DIV>
+
+You can control the minimum and maximum length for a password by setting the _ads-pwdMinLength_ and _ads-pwdMaxLength_ attributes.
 
+<DIV class="warning" markdown="1">
+Setting a password max length is most certainly a waste of time. It's very likely that this parameter has been added to the specification for the sake of symetry...
+</DIV>
\ No newline at end of file