Troubleshooting Linux SASL Issues

SASL as a framework comes in handy in an array of applications. But more importantly, the Simple Authentication and Security Layer is an authentication, encryption, and data security method in email protocols. These functionalities make it an incredibly vital resource for the server and mail system administrators.But like every other authentication protocols or frameworks, using the Linux SASL could also result in an array of errors. This article will look into some of the common SASL errors as well as their respective solutions.

But before that, let us highlight the general error codes that your SASL system may return after a call to the library. Of course, we will also state what their general meanings are:

Common SASL Result Codes

SASL_OK – Successful operation.
SASL_CONTINUE- Another step is needed to complete the authentication or procedure.
SASL_FAIL- Generic operation failure.
SASL_MOMEN- Failure due to memory shortage.
SASL_NOMECH- The mechanism in use is not supported. Alternatively, there is no mechanism in the system that matches your requirements.
SASL_BADPROT- Invalid/ bad protocol.
SASL_NOTDONE– The information requested is not applicable or the information in question cannot be requested.
SASL_NOTINIT- The library is not initialized.
SASL_TRYAGAIN- An error indicating a transient failure.
SASL_BADMAC- A failed integrity check.

Common Client SASL Client-Only Result Codes

SASL_WRONGMECH- The mechanism in use does not support the requested feature.
SASL_INTERACT- There is a need for interaction with the user.
SASL_BADSERV- The server failed at the mutual authentication step.

Common SASL Server-Only Codes

SASL_BADAUTH- An authorization failure.
SASL_TOOWEAK- The mechanisms in use are too weak for the user.
SASL_NOAUTHZ- An authorization failure.
SASL_TRANS- A single use of a plaintext password can easily permit the requested mechanism for the user.
SASL_EXPIRED- Expiry of a paraphrase; you should reset.
SASL_TOOWEAK- The mechanism in use is too weak for the user.
SASL_ENCRYPT- You need an encryption for the mechanism in use.
SASL_DISABLED- The SASL account in use is disabled.
SASL_NOUSER- User has not been found.
SASL_NOVERIFY- User exists in the system. However, there is no verifier for the user.
SASL_BADVERS- The version in question mismatches the plugin.

SASL Result Codes that Come with Password Setting

SASL_NOCHANGE- The requested change is not necessary.
SASL_WEAKPASS- The password provided is too weak.
SASL_PWLOCK- The paraphrase mode is locked.
SASL_NOUSERPASS- The password supplied by the user is not correct/ verifiable.

Common SASL Errors You Should Know

The following are some common problems that you may face when interacting with SASL:

Incorrect Username/Password on SASL Used with SASL

If you are using the SASL framework and authenticating with Kerberos, the following issues can occur:

The solution to the previous issues is to ensure that you enter the username and password correctly. The username is very case-sensitive whenever you are using the Kerberos version 5 and SASL for authentication.

SASL_FAIL When Using SMTP

Usually, this signifies a generic failure. It occurs when your SMTP authorization is faulty and not working normally. Of course, this can even happen when you key in a valid email login credentials.

The exact log files will read as follows:

Solving this entails sorting out the poor configuration plugin. Besides, you can avoid sending emails using the secure ports such as 465 or 467, among others.

SASL Issues When Using SASL and Postfix SMTP

When using SASL on Postfix SMTP, the following error often occurs. It happens because of a wrong configuration of the /etc/postfix/master.cf file on TLS. You can solve this problem by slightly tweaking the smtpd_enforce_tls variable. You can set its value in /etc/postfix/master.cf file to become mtpd_enforce_tls = yes.

The entries should resemble what’s in the following figure after the edits:

Besides the edits, ensure that your configuration file doesn’t have any incorrect data.

An Authentication Error When Using SASL on DIGEST-MD5

An error can occur because the connector does not have an Extra Provider Parameter.

You can add the java.naming.security.authentication:DIGEST-MD5 to the appropriate Extra Provider Parameter section after selecting the SASL authentication method.

Conclusion

That is all about the SASL troubleshooting. Notably, SASL troubleshooting errors often occur due to wrong configuration or poor callback steps. This article aimed at discussing the common errors. True to its objective, we handled some of the common errors that you will most likely face. Should you face any errors that are not handled in this list, please share those with us in the comment section below.

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