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-See http://hyperstruct.net/projects/spock.
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+# spock
+A command-line tool to sign update manifests of Mozilla extensions
+
+## What is this?
+spock signs a Mozilla extension manifest (update.rdf) file and optionally sets a value for <version/>, <updateLink/>, and <updateHash/>.
+
+It was hacked together as a non-interactive replacement to McCoy.
+
+## Prerequisites
+- libxml
+- libxslt
+- ruby, with bindings to libxml and libxslt
+
+You should have created a key with McCoy. The key must not be protected with a password. If there is more than one key, the first one will be used.
+
+spock, normalize_update_rdf.rb, nss_sign_data and rdf2nt.xsl must be in the same directory.
+Additionally, on Debian Sid, I used these packages, plus their *-dev counterparts:
+
+- libnss3-1d
+- libnspr4-0d
+
+These are needed on Fedora instead (thanks, Godmar!). Include files will be placed in /usr/include/nss3 and /usr/include/nspr4, requiring a Makefile change:
+
+-nss-devel
+-nss
+-nspr-devel
+-nspr
+
+See Godmar's comment below for more instructions about Fedora.
+
+## Usage
+
+```
+Usage: spock [options] FILE
+    -i, --extension-id ID            ID of the extension resource, including version if any
+                                     Examples:
+                                     urn:mozilla:extension:foo@bar.org:0.1
+                                     urn:mozilla:extension:{eecba28f-b68b-4b3a-b501-6ce12e6b8696}
+    -v, --version VERSION            Set  value in resulting update.rdf
+    -u, --update-link URL            Set  value in resulting update.rdf
+    -f, --file PACKAGE_FILENAME      Determine  value using PACKAGE_FILENAME
+    -d, --nss-directory DIR          Directory containing key key3.db
+                                     Example: ~/.mozilla/mccoy/rt7xxbxw.default/
+
+    -h, --help                       This help text
+```
+
+## Simple example:
+
+$ ./spock update.rdf -i urn:mozilla:extension:{eecba28f-b68b-4b3a-b501-6ce12e6b8696} -d ~/.mozilla/mccoy/rt7xxbxw.default/ > update.rdf.signed
+
+## Advanced example:
+
+$ ./spock update.rdf -i urn:mozilla:extension:{eecba28f-b68b-4b3a-b501-6ce12e6b8696} -d ~/.mozilla/mccoy/rt7xxbxw.default/ -v 0.1.0 -u http://my.site.com/extensions/ext.xpi -f ext.xpi > update.rdf.signed
+
+## Limitations
+update.rdf must be valid XML. Note that Mozilla reading the file correctly does not ensure that it will be valid for libxml. Common issues include about= and resource= attributes being unqualified (so if you have an xmlns:RDF= at the top, make sure you write RDF:about= and RDF:resource=). You might want to use include sample.update.rdf as a guide for your own.
+
+Only the first key in McCoy database is used, and it must not be protected by a password.
+
+Only one extension per update.rdf is supported.
+
+The input update.rdf must not contain an <signature/> element already.
+
+update.rdf must already contain <updateLink/> and <updateHash/> tags, even if empty. Spock won't add them.
+
+## Credits
+For rtf2nt.xsl, see file.
+
+normalize_update_rdf.rb is a direct translation (minus mistakes, mine) of Dave Townsend’s rdfserializer.js from McCoy. Much of nss_sign_data.c has been adapted from there too.
+
+Content of the nss/ directory comes from libnss3.
+
+A big thank-you to dafi (Davide Ficano) for helping with testing.
+
+## Important notice
+This software is NOT endorsed by Mozilla.
+
+This software is also NOT supported by the author. Use at your own risk.