From 289855c9d1fee5744c8cbaf318d59f42e744fc5f Mon Sep 17 00:00:00 2001 From: Goffi Date: Sun, 30 Oct 2022 01:06:58 +0200 Subject: [PATCH] doc (encryption, cli): pubsub signing documentation: - add a `Pubsub Signature` section to `encryption` documentation - document `-X, --sign` flag where it's used - document `pubsub/signature` subcommands fix 381 --- doc/conf.py | 7 ++++++ doc/encryption.rst | 33 +++++++++++++++++++++++++ doc/libervia-cli/blog.rst | 4 +++ doc/libervia-cli/pubsub.rst | 9 +++++++ doc/libervia-cli/pubsub_signature.rst | 35 +++++++++++++++++++++++++++ 5 files changed, 88 insertions(+) create mode 100644 doc/libervia-cli/pubsub_signature.rst diff --git a/doc/conf.py b/doc/conf.py index 07aa3c22..5c6bc111 100644 --- a/doc/conf.py +++ b/doc/conf.py @@ -47,6 +47,13 @@ rst_prolog = """ To publish an end-to-end encrypted item, you can use the ``-e, --encrypt`` flag, and share secrets with :ref:`libervia-cli_pubsub_secret`. Please read :ref:`pubsub-encryption` for more details. + +.. |sign_arg| replace:: + To cryptographically sign an item, you can use the ``-X, --sign`` flag (a mnemonic way + to remember the short option is to think of a cross made as a signature on a document). + Signature can then be checked with :ref:`libervia-cli_pubsub_signature`. Please read + :ref:`pubsub-encryption` for more details. + """ # If your documentation needs a minimal Sphinx version, state it here. diff --git a/doc/encryption.rst b/doc/encryption.rst index d17757ff..9dc54908 100644 --- a/doc/encryption.rst +++ b/doc/encryption.rst @@ -92,3 +92,36 @@ To handle encrypted pubsub node shared secrets from command line, you may use .. _OpenPGP: https://en.wikipedia.org/wiki/Pretty_Good_Privacy#OpenPGP +Pubsub Signature +================ + +By default, identity of the publisher of a pubsub item is difficult to authenticate: it +may be specified by the pubsub service (using the `"publisher" attribute`_), but this +attribute is not set by all pubsub services, and it can be spoofed by the service or the +XMPP server. + +To strongly authenticate the publisher of a pubsub item, it is possible to cryptographically sign an item. This can work with any pubsub item, encrypted or not, and it can be done after the item has been published. The process use `Pubsub Signing protoXEP`_ + +.. note:: + + Pubsub Signing specification is not currently an official XEP (XMPP Extension + Protocol), it is about to be examinated by "XMPP council". This documentation will be + updated with the evolution of the situation. + +.. attention:: + + Signature only certifies that the signers strongly link themselves with this version of + the item, not that the signers are the original authors of the item. In other words, it + prevents somebody to say that somebody else has published something (the signature + would be missing or invalid), but the published data may come from anywhere. Also keep + in mind that a security breach (stolen encryption keys, major bug somewhere) is always + possible. + + +To handle pubsub signatures from command line, you may use +:ref:`libervia-cli_pubsub_signature`. + +.. _"publisher" attribute: https://xmpp.org/extensions/xep-0060.html#publisher-publish-success-publisher + +.. _Pubsub Signing protoXEP: https://github.com/xsf/xeps/pull/1228 + diff --git a/doc/libervia-cli/blog.rst b/doc/libervia-cli/blog.rst index 971cb4b8..538f4ac4 100644 --- a/doc/libervia-cli/blog.rst +++ b/doc/libervia-cli/blog.rst @@ -18,6 +18,8 @@ publish a blog item. |e2e_arg| +|sign_arg| + examples -------- @@ -107,6 +109,8 @@ configuration `_ below to see how to do. |e2e_arg| +|sign_arg| + examples -------- diff --git a/doc/libervia-cli/pubsub.rst b/doc/libervia-cli/pubsub.rst index a8b034ef..55bab2f6 100644 --- a/doc/libervia-cli/pubsub.rst +++ b/doc/libervia-cli/pubsub.rst @@ -26,6 +26,8 @@ you need to specify the full option name. |e2e_arg| +|sign_arg| + .. _XEP-0060 ยง7.1.5: https://xmpp.org/extensions/xep-0060.html#publisher-publish-options example @@ -83,6 +85,8 @@ If you don't change anything or publish an empty blog post, the edition will be |e2e_arg| +|sign_arg| + example ------- @@ -458,6 +462,11 @@ attachments Subcommands to add or remove data attached to pubsub items. Please check :ref:`libervia-cli_pubsub_attachments`. +signature +========= + +Subcommands to handle items signature. Please check :ref:`libervia-cli_pubsub_signature`. + secret ====== diff --git a/doc/libervia-cli/pubsub_signature.rst b/doc/libervia-cli/pubsub_signature.rst new file mode 100644 index 00000000..82d657b8 --- /dev/null +++ b/doc/libervia-cli/pubsub_signature.rst @@ -0,0 +1,35 @@ +.. _libervia-cli_pubsub_signature: + +================================================= +pubsub/signature: Sign and Check Items Signatures +================================================= + +``signature`` group commands to handle pubsub item cryptographic signatures: + +You can check :ref:`pubsub-encryption` to have overview on how it works. + +sign +===== + +Sign a pubsub item using OpenPGP keys of the profile. + +example +------- + +Louise want to sign an item on her blog:: + + $ li pubsub signature sign -s louise@example.net -n urn:xmpp:microblog:0 -i about_feminism + +check +===== + +Check validity of a signature found in attachments. For now, the attachments data JSON as +found in attachments must be used, it is planned to make this command simpler in the close +future. + +example +------- + +Pierre wants to check that a blog post is really from Louise:: + + $ li pubsub signature check -s louise@example.net -n urn:xmpp:microblog:0 -i about_feminism '{"timestamp": 1667079677.0, "signers": ["louise@example.net"], "signature": "iQGzBAABCAAdFiEEeTqK7iUsJz97sLSEgjG1Of9Gvi0FAmNdnf0ACgkQgjG1Of9Gvi293Qv+IWe6gkaAPzGI6fis9yg9biSdFE9qf9oi+jyTiZuTR1QjjZYE7x+vsj3KewKBUMOyqxKMk1WVKmimDb3yCqfF852lEox3OQuBMP46G9UHDNII6D+oqe4VVWZhqe3s3twWYc08nrvAUH4tMI96xml4wuEk6Fv8PwBcNEEzX8zNwLYeY6tsR72XErBDn5oY06OGhZeLBn6FkUI1QZ3jT0djjH87CuH+9gOS6vEIpO+UnCqvB3aqxwhHIIOh5X9bUyEyxINb3kA6WpYumlc92vE8ROndPZGEni9OfouTjJL7+tUmcNz4RJdbEzBpETtzJ4B3r/kbJWKi5YDpZZOI1k/W/eKXFIg6Aycc0iG/THSEwvYMFGrmyQYosdC+mbjSE4DvYE1aSHOLW3ut5kNuDqLH17/kyOh+VoR4FAkRtGoa34sQN2jaRG8m/Gl+98Ha67k8OisnrHOx7FKGGcrpEp+BCUgvNP0IRFCz26xSaZ6aXK2SQkcvlbVXf6o0BkE5Hwcn"}'