#354 DCO
About the Developer Certificate of Origin and how to support it with git
Notes
The Developer Certificate of Origin (DCO) is a mechanism for contributors to certify that they wrote or otherwise have the right to submit the code they are contributing to the project.
It appears increasingly common for open-source projects to require DCO compliance, perhaps largely to address concerns over supply-chain attacks.
A typical signed-off commit message would look like this:
This is my commit message
Signed-off-by: Random J Developer <random@developer.example.org>
The DCO was created in 2004 by the Linux Foundation for the Linux kernel project, following licensing and copyright concerns. Instead of requiring every contributor to sign a legal document, the DCO allowed developers to simply include a “Signed-off-by” statement in each commit message.
The full text of the DCO:
Developer Certificate of Origin
Version 1.1
Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
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.
How to comply using git
Git has a -s command line option to append this automatically to your commit message:
git commit -s -m 'This is my commit message'
To ensure sign-off is applied to every commit in a repo, can add a hook template as follows:
$ cat > .git/hooks/prepare-commit-msg << EOT
#!/bin/sh
SOB=\$(git var GIT_AUTHOR_IDENT | sed -n 's/^\(.*>\).*$/Signed-off-by: \1/p')
grep -qs "^\$SOB" "\$1" || echo "\\n\$SOB" >> "\$1"
EOT
$ chmod u+x .git/hooks/prepare-commit-msg
$ cat .git/hooks/prepare-commit-msg
#!/bin/sh
SOB=$(git var GIT_AUTHOR_IDENT | sed -n 's/^\(.*>\).*$/Signed-off-by: \1/p')
grep -qs "^$SOB" "$1" || echo "\n$SOB" >> "$1"