Problem

You want to store employee Social Security numbers as encrypted data as required by government regulations or industry standards. Only select certain users should be able to view the entire social security number; all other users should only be able to view the last four digits. In addition, you want to ensure that users enter the numbers in the standard social security number format, including the dashes after the third and fifth digits.

Solution

1. Define the encrypted custom field.
   1. Click Setup | Customize | Users | Fields.
   2. In the User Custom Fields related list, click New.
   3. Select Text (Encrypted), and click Next.
   4. In the Field Label field, enter Social Security Number.
   5. In the Length field, enter 11. This allows the field to accept all nine digits of the Social Security number plus the dashes after the third and fifth digits.
   6. In the Description field, enter Encrypted Social Security Number field.
   7. In the Help Text field, enter information to help your users understand what value to type. For example, Enter your Social Security number. Remember to include dashes after the third and fifth digits.
   8. In the Mask Type field, select Social Security Number. This option hides the first five digits (it hides the first 7 characters) and displays the last four. Only users with profiles that have the “View Encrypted Data” permission selected are able to view all nine digits of the Social Security number.
   9. In the Mask Character field, select the character, either an asterisk (*) or an X, to use for hidden characters.
   10. Click Next.
   11. In Enterprise, Unlimited, and Developer Editions, set the field-level security to determine whether the field should be visible or read only for specific profiles. These settings determine whether or not the field itself is visible, but do not affect whether or not the user sees the masked or full Social Security number. You will specify the type of masking when you create the custom profile.
   12. Click Next.
   13. Leave the Add Field and User Layout checkboxes selected.
   14. Click Save.
2. Create the validation rule.
   1. Click Setup | Customize | Users | Validation Rules.
   2. Click New.
   3. In the Rule Name field, enter Social Security Number Format Check.
   4. In the Description field, enter Validates that the Social Security Number is in the correct format.
   5. Enter the following error condition formula:

      NOT(
      OR(
      LEN (Social_Security_Number__c) = 0,
      REGEX( Social_Security_Number__c , "[0-9]{3}-[0-9]{2}-[0-9]{4}")
      )
      )
   6. Click Check Syntax to make sure the syntax is correct.
   7. In the Error Message field, enter a message that appears if the user enters a Social Security number in an invalid format. For example, the message might read: The Social Security number you entered is not in the correct format. The correct format is 999-99-9999.
   8. In the Error Location field, specify whether you want the error message you entered above to appear at the top of the page or next to the field. If you choose Field, select the Social Security Number field in the adjacent drop-down list.
   9. Click Save.
3. Create the custom profile.
   1. Click Setup | Manage Users | Profiles.
   2. Click New.
   3. Select an existing profile to copy.
   4. Name the new custom profile.
   5. Click Save.
   6. Click Edit.
   7. In the General User Permissions section, select the View Encrypted Data checkbox. This allows users with this profile to see the complete value of encrypted fields instead of the masking characters.
   8. Click Save.
4. Assign the new custom profile to the users allowed to view the encrypted data.

Discussion

Government regulations and industry standards require many companies to use encryption to protect their most sensitive employee and customer data. Encrypted custom fields can help companies comply with these regulations. Salesforce.com encrypts these fields with 128-bit keys and uses the AES (Advanced Encryption Standard) algorithm which has been adopted as an encryption standard by the U.S. government. Encrypted custom fields should only be used when regulations require encryption because they involve additional processing and have search-related limitations.

To further protect the confidentiality of encrypted custom field values, Salesforce.com requires you to specify a mask type for each encrypted field you create. Character masking lets you hide the characters in encrypted field values, allowing users to see the full value of an encrypted custom field only if their profile has the “View Encrypted Data” permission. If your company uses parts of confidential data, such as the last four digits of a person's Social Security or credit card number, to verify the identity of customers, configure your encrypted custom fields to use a mask type that reveals only the those digits, such as the Last Four Characters Clear mask type.

In addition to ensuring your data's confidentiality, you also want to ensure its accuracy. Validation rules improve the quality of your data by verifying that the data a user enters in a record meets the standards you specify before the user can save the record. A validation rule contains a formula expression that evaluates the data in one or more fields and returns a value of “True” or “False.” If the validation rule returns “True,” Salesforce.com lets the user save the record; otherwise, Salesforce.com displays an error message.

The validation rule in this recipe uses the REGEX() function, which compares the custom field to a regular expression. A regular expression is a string used to describe a format of a string according to certain syntax rules. Salesforce.com regular expression syntax is based on Java Platform SE 6 syntax ; however, backslash characters (\) must be changed to double backslashes (\\) because backslash is an escape character in Salesforce.com.