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(Add second owner: fweimer)
(Add information about scope and testing instructions)
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== Scope ==
 
== Scope ==
 
* Proposal owners:
 
* Proposal owners:
* Other developers:  
+
** Apply needed packaging changes to glibc
* Release engineering: [https://pagure.io/releng/issues #Releng issue number] (a check of an impact with Release Engineering is needed)
+
** Import and build libxcrypt for Fedora 28
** [[Fedora_Program_Management/ReleaseBlocking/Fedora{{FedoraVersionNumber|next}}|List of deliverables]]:  
+
 
* Policies and guidelines:
+
* Other developers:
 +
** Test their applications using one of the following interfaces for unexpected changes in functionality:
 +
*** crypt()
 +
*** crypt_r()
 +
*** encrypt()
 +
*** encrypt_r()
 +
*** fcrypt()
 +
*** setkey()
 +
*** setkey_r()
 +
 
 +
* Release engineering: [https://pagure.io/releng/issue/7160 #7160]
 +
<!-- ** [[Fedora_Program_Management/ReleaseBlocking/Fedora{{FedoraVersionNumber|next}}|List of deliverables]]: -->
 +
* Policies and guidelines: N/A (not needed for this Change)
 
* Trademark approval: N/A (not needed for this Change)
 
* Trademark approval: N/A (not needed for this Change)
  
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== How To Test ==
 
== How To Test ==
  
 
+
* Logout of your current user session and check if you can login again.
 +
* Change your user password and check if you can login with the new one.
 +
* Check if all packages built against libcrypt are working as expected.  You can get a list of those packages with the following command:  `sudo dnf repoquery --whatrequires 'libcrypt.so*' | sed -e 's!-[0-9]\+.*$!!g' | sort -u`
  
  

Revision as of 13:36, 13 November 2017

Replace glibc's libcrypt with libxcrypt

Summary

There are plans to remove libcrypt from glibc, so we should have a replacement.


Owner


Current status

  • Targeted release: Fedora 28
  • Last updated: 2017-11-13
  • Tracker bug: <will be assigned by the Wrangler>


Detailed Description

Since there has been some discussion in the last time about removing libcrypt from glibc in some time and splitting it out into a separate project which can evolve quicker, Zack Weinberg and I put some work into libxcrypt to make it a basically suitable replacement.

libxcrypt is fully binary compatible with software linked against glibc's libcrypt and does not require any rebuilds. However, the converse is not true: programs linked against libxcrypt will not work with glibc's libcrypt. Also, programs that use certain legacy APIs supplied by glibc's libcrypt (encrypt, encrypt_r, setkey, setkey_r, and fcrypt) cannot be compiled against libxcrypt.

It comes with a set of extended interfaces pioneered by Openwall Linux, crypt_rn, crypt_ra, crypt_gensalt, crypt_gensalt_rn, and crypt_gensalt_ra.

The crypt and gensalt functions are supporting all (except for Crypt16, which was used on Ultrix and Tru64, only) widely used password hashing algorithms, which before were specific to just some operating system's implementations of libcrypt.


Benefit to Fedora

Scope

  • Proposal owners:
    • Apply needed packaging changes to glibc
    • Import and build libxcrypt for Fedora 28
  • Other developers:
    • Test their applications using one of the following interfaces for unexpected changes in functionality:
      • crypt()
      • crypt_r()
      • encrypt()
      • encrypt_r()
      • fcrypt()
      • setkey()
      • setkey_r()
  • Release engineering: #7160
  • Policies and guidelines: N/A (not needed for this Change)
  • Trademark approval: N/A (not needed for this Change)


Upgrade/compatibility impact

How To Test

  • Logout of your current user session and check if you can login again.
  • Change your user password and check if you can login with the new one.
  • Check if all packages built against libcrypt are working as expected. You can get a list of those packages with the following command: sudo dnf repoquery --whatrequires 'libcrypt.so*' | sed -e 's!-[0-9]\+.*$!!g' | sort -u


User Experience

Dependencies

Contingency Plan

  • Contingency mechanism: Revert changes and restore glibc's libcrypt
  • Contingency deadline: Completion deadline (testable)
  • Blocks release? Yes
  • Blocks product? none


Documentation

Release Notes