Developer Certificate Of Origin

From eLinux.org
Revision as of 10:12, 29 January 2020 by Tim Bird (talk | contribs) (Resources: Use correct wiki syntax)
Jump to: navigation, search

In May 2004, the kernel development community decided to standardize on a requirement to adhere to a Developer Certificate of Origin for contributions to the Linux kernel.

The text of the DCO is located in the file Documentation/process/submitting-patches.rst in the Linux kernel source tree.

The full text of the DCO version 1.1 (the current version as of 2011) is:

        Developer's Certificate of Origin 1.1

        By making a contribution to this project, I certify that:

        (a) The contribution was created in whole or in part by me and I
            have the right to submit it under the open source license
            indicated in the file; or

        (b) The contribution is based upon previous work that, to the best
            of my knowledge, is covered under an appropriate open source
            license and I have the right under that license to submit that
            work with modifications, whether created in whole or in part
            by me, under the same open source license (unless I am
            permitted to submit under a different license), as indicated
            in the file; or

        (c) The contribution was provided directly to me by some other
            person who certified (a), (b) or (c) and I have not modified
            it.

        (d) I understand and agree that this project and the contribution
            are public and that a record of the contribution (including all
            personal information I submit with it, including my sign-off) is
            maintained indefinitely and may be redistributed consistent with
            this project or the open source license(s) involved.

There is a kernel thread discussing the original proposal from Linus here (lkml.org), and here (google groups). And here (aimsgroup).

Here is another article describing rationale for the 1.1 version: Clarifying the Developer's Certificate of Origin KernelTrap, June 14, 2005

Example

Here is an example Signed-off-by line, that indicates the submitter accepts the DCO:

Signed-off-by: John Doe <john.doe@hisdomain.com>

Resources

  • Using '-s' with 'git commit' will automatically add a Signed-off-by line to your commit message.
  • The kernel tool checkpatch.pl scans kernel patches for errors, and will indicate if the Signed-off-by line is missing.

Here is what a checkpatch.pl error for missing SoB looks like:

$ scripts/checkpatch.pl init/0001-main-add-debug-printk.patch 
ERROR: Missing Signed-off-by: line(s)

total: 1 errors, 0 warnings, 7 lines checked 

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.
init/0001-main-add-debug-printk.patch has style problems, please review.

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.

Older versions

The original DCO, version 1.0, read:

    Developer's Certificate of Origin 1.0

    By making a contribution to this project, I certify that:

    (a) The contribution was created in whole or in part by me and I have the right
    to submit it under the open source license indicated in the file; or

    (b) The contribution is based upon previous work that, to the best of my knowledge,
    is covered under an appropriate open source license and I have the right under that
    license to submit that work with modifications, whether created in whole or in part
    by me, under the same open source license (unless I am permitted to submit under a
    different license), as indicated in the file; or

    (c) The contribution was provided directly to me by some other person who
    certified (a), (b) or (c) and I have not modified it.