Manifest

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Describe SecurityTeam/Specifications/ApplicationConfinement/Manifest here. = Manifest file - security (DRAFT) =

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= Overview =
http://bazaar.launchpad.net/~click-hackers/click/trunk/view/head:/doc/file-format.rst
discusses the manifest file format for click packages in general. This page
discusses the security section of the JSON manifest. Click packages will
contain the toplevel 'security' key, and the 'security' object is a dictionary
with each subkey being the name of a profile object (also a dictionary). The '''aa-easyprof''' tool is used to
parse the security section of the manifest and generate an !AppArmor profile.
'''aa-easyprof''' will be used by click via a hook to install !AppArmor policy.
For more details on '''aa-easyprof''', see `man 8 aa-easyprof`. An example
manifest representing all possible keys is: {{{
{
  "name": "Name used by click",
  "version": "Version used by click>",
  "framework": "Framework used by click",
  "security": {
    "com.example.foo": {
      "abstractions": [
        "audio",
        "gnome"
      ],
      "author": "Your Name",
      "binary": "/opt/foo/**",
      "comment": "Unstructured single-line comment",
      "copyright": "Unstructured single-line copyright statement",
      "name": "My Foo App",
      "policy_groups": [
        "networking",
        "user-application"
      ],
      "policy_vendor": "somevendor",
      "policy_version": 1.0,
      "read_path": [
        "/tmp/foo_r",
        "/tmp/bar_r/"
      ],
      "template": "user-application",
      "template_variables": {
        "APPNAME": "foo",
        "APPVERSION": "0.1",
        "VAR1": "bar",
        "VAR2": "baz"
      },
      "write_path": [
        "/tmp/foo_w",
        "/tmp/bar_w/"
      ]
    }
  }
}
}}}

== Security keys ==
aa-easyprof is a general purpose tool and all of the security keys within a profile object are optional.
 * '''profile name''': keys to the 'security' dictionary are the profile names for each profile object. Therefore in the above example, "com.example.foo" is the profile name and the contents of the "com.example.foo" dictionary represent the profile. The profile name may specify the normalized absolute path to the binary (with AARE (see `apparmor.d(8)`) or an name that contains '[a-zA-Z0-9 \.\-_]'.
 * '''binary''': path to binary for this policy when using path-based attachment. Should not be specified when the profile name is an absolute path
 * '''author''': author of the policy
 * '''comment''': comment for the policy
 * '''copyright''': copyright of the policy
 * '''name''': name of policy. If not specified, use the name of the binary. Note, this is not the !AppArmor profile name.
 * '''policy_vendor''': vendor of policy groups and templates ([a-zA-Z_0-9\-\.])
 * '''policy_version''': version of the vendor policy (float)
 * '''template''': template to use ([a-zA-Z_0-9\-\.])
 * '''template_variables''': list of template variable assignments. Supported template variables are template-specific
 * '''abstractions''': list of !AppArmor abstractions to include (typically from /etc/apparmor.d)
 * '''policy_groups''': list of !AppArmor policy groups to include ([a-zA-Z_0-9\-\.])
 * '''read_path''': list of paths to allow read access
 * '''write_path''': list of paths to allow write access

== Use in Ubuntu ==
=== Click ===
Click packages in Ubuntu are required to run under application confinement and therefore the manifest file must contain a security section. As such, some fields are required, some unused and some are technically supported but dangerous and will red flag the package for manual review.
 * Required fields
  * JSON profile object (ie, the '''profile name''' key and its corresponding dictionary)
  * '''policy_vendor''' should be set to '''ubuntu'''
  * '''policy_version''' should be set. '''1.0''' is the first supported Ubuntu policy version. For other versions, see /usr/share/apparmor/easyprof/templates/ubuntu/ and /usr/share/apparmor/easyprof/policygroups/ubuntu/
  * '''binary''' - should be set as a '''recursive glob on the toplevel installation directory'''. Eg, if the app is installed to `/opt/com.ubuntu.developer/com.ubuntu.developer.username.myapp`, then binary should be set to `/opt/com.ubuntu.developer/com.ubuntu.developer.username.myapp/**`
  * '''template''' - defaults to 'default' which is a symlink to ubuntu-sdk. See `aa-easyprof --policy-vendor=ubuntu --policy-version=1.0 --list-templates` (using the appropriate vendor version) for a list of other templates
  * '''template_variables''' - the Ubuntu templates support setting the following variables:
   * '''APPNAME''' - typically the '''reverse domain''' (eg, com.ubuntu.developer.username.appname)
   * '''APPVERSION''' - application version

  These are used to differentiate application paths. Eg, the resulting !AppArmor policy will have something like:{{{
 @{APPNAME}="com.ubuntu.developer.username.myapp"
 @{APPVERSION}="0.1"
 ...
   /opt/click.ubuntu.com/@{APPNAME}/@{APPVERSION}/ r,
   /opt/click.ubuntu.com/@{APPNAME}/@{APPVERSION}/** r,
   /opt/click.ubuntu.com/@{APPNAME}/@{APPVERSION}/**/ r,
}}}
  * '''policy_groups''' - these are used to grant permissions to the app, such as networking, online accounts, content picking, etc. Some policy groups might always be used (and therefore pre-filled), such as `qmlscene` while others will only be used by some apps (eg, `qmlscene-webview` for HTML5 apps). See `aa-easyprof --policy-vendor=ubuntu --policy-version=1.0 --list-policy-groups` for a complete list
 * Unused/ignored
  * name
  * author
  * comment
  * copyright
 * Red-flagged for manual review (use should actively be discouraged with updates made to policy groups and templates)
  * abstractions
  * read_path
  * write_path

=== Traditional packaging ===
Traditional packaging can also leverage aa-easyprof, but the process is slightly more involved. In general, the following need to happen (see `man dh_apparmor` for details):
 * the manifest file (only the security section is needed) is added to debian/. Because traditional packaging has different governance rules for including in a distribution, the manifest may contain any of the supported fields
 * aa-easyprof is given the manifest file to generate a profile
 * the profile is installed into a package
 * the postinst loads the !AppArmor policy into the kernel

The process is made easier with `dh_apparmor`. Create a manifest file following the above instructions then:
 0. put the manifest file in debian/manifest.json
 0. adjust debian/control to Build-Depends on `dh-apparmor >= 2.8.0-0ubuntu14`
 0. update debian/rules to call dh_apparmor. Eg:{{{
override_dh_install:
        dh_apparmor -p<deb binary> --profile-name=<profile name from the manifest> --manifest=manifest.json
        dh_install
}}}
 and then to clean up:{{{
override_dh_clean:
        dh_clean
        rm -rf debian/apparmor
}}}
 0. install the files. Eg, add to `debian/<deb binary>.install`:{{{
debian/apparmor/<profile name> etc/apparmor.d
}}}

The remaining consideration is making sure that the app runs confined. You'll know you have it right if when the application is running, the output of `aa-status` shows that the application is confined. If the application provides an executable (eg, ELF binary, executable python script), then specifying the 'binary' in the manifest is enough. If instead a helper such as qmlscene is being used, there are several choices:
 * use the new Ubuntu application lifecycle and start the application via an Upstart job (preferred, pending but not available as of 2013/07/02)
 * add `XCanonicalAppArmorProfile=<profile name>` to the .desktop file until Ubuntu application lifecycle is finished (not available as of 2013/07/02)
 * update the .desktop file so use `aa-exec -p <profile name> ...` in the Exec line. Unfortunately there is an issue using aa-exec in .desktop files, which may be related to glib
 * Create a shell script to use `aa-exec -p <profile name> ...` and have the .desktop file use `Exec=<path to shell script>`

=== Bugs ===
When filing bugs dealing with the manifest file or resulting permissions, please use one of the below and use the 'application-confinement' tag:
 * [[https://bugs.launchpad.net/ubuntu/+source/apparmor-easyprof-ubuntu/+filebug|bugs against !AppArmor policy for SDK applications]]
 * [[https://bugs.launchpad.net/ubuntu/+source/apparmor/+filebug|general bugs against aa-easyprof]]
 * [[https://bugs.launchpad.net/ubuntu-qtcreator-plugins/+filebug|policy bugs that should be resolved in the SDK]]

Manifest file - security (DRAFT)

Overview

http://bazaar.launchpad.net/~click-hackers/click/trunk/view/head:/doc/file-format.rst discusses the manifest file format for click packages in general. This page discusses the security section of the JSON manifest. Click packages will contain the toplevel 'security' key, and the 'security' object is a dictionary with each subkey being the name of a profile object (also a dictionary). The aa-easyprof tool is used to parse the security section of the manifest and generate an AppArmor profile. aa-easyprof will be used by click via a hook to install AppArmor policy. For more details on aa-easyprof, see man 8 aa-easyprof. An example manifest representing all possible keys is:

{
  "name": "Name used by click",
  "version": "Version used by click>",
  "framework": "Framework used by click",
  "security": {
    "com.example.foo": {
      "abstractions": [
        "audio",
        "gnome"
      ],
      "author": "Your Name",
      "binary": "/opt/foo/**",
      "comment": "Unstructured single-line comment",
      "copyright": "Unstructured single-line copyright statement",
      "name": "My Foo App",
      "policy_groups": [
        "networking",
        "user-application"
      ],
      "policy_vendor": "somevendor",
      "policy_version": 1.0,
      "read_path": [
        "/tmp/foo_r",
        "/tmp/bar_r/"
      ],
      "template": "user-application",
      "template_variables": {
        "APPNAME": "foo",
        "APPVERSION": "0.1",
        "VAR1": "bar",
        "VAR2": "baz"
      },
      "write_path": [
        "/tmp/foo_w",
        "/tmp/bar_w/"
      ]
    }
  }
}

Security keys

aa-easyprof is a general purpose tool and all of the security keys within a profile object are optional.

  • profile name: keys to the 'security' dictionary are the profile names for each profile object. Therefore in the above example, "com.example.foo" is the profile name and the contents of the "com.example.foo" dictionary represent the profile. The profile name may specify the normalized absolute path to the binary (with AARE (see apparmor.d(8)) or an name that contains '[a-zA-Z0-9 \.\-_]'.

  • binary: path to binary for this policy when using path-based attachment. Should not be specified when the profile name is an absolute path

  • author: author of the policy

  • comment: comment for the policy

  • copyright: copyright of the policy

  • name: name of policy. If not specified, use the name of the binary. Note, this is not the AppArmor profile name.

  • policy_vendor: vendor of policy groups and templates ([a-zA-Z_0-9\-\.])

  • policy_version: version of the vendor policy (float)

  • template: template to use ([a-zA-Z_0-9\-\.])

  • template_variables: list of template variable assignments. Supported template variables are template-specific

  • abstractions: list of AppArmor abstractions to include (typically from /etc/apparmor.d)

  • policy_groups: list of AppArmor policy groups to include ([a-zA-Z_0-9\-\.])

  • read_path: list of paths to allow read access

  • write_path: list of paths to allow write access

Use in Ubuntu

Click

Click packages in Ubuntu are required to run under application confinement and therefore the manifest file must contain a security section. As such, some fields are required, some unused and some are technically supported but dangerous and will red flag the package for manual review.

  • Required fields
    • JSON profile object (ie, the profile name key and its corresponding dictionary)

    • policy_vendor should be set to ubuntu

    • policy_version should be set. 1.0 is the first supported Ubuntu policy version. For other versions, see /usr/share/apparmor/easyprof/templates/ubuntu/ and /usr/share/apparmor/easyprof/policygroups/ubuntu/

    • binary - should be set as a recursive glob on the toplevel installation directory. Eg, if the app is installed to /opt/com.ubuntu.developer/com.ubuntu.developer.username.myapp, then binary should be set to /opt/com.ubuntu.developer/com.ubuntu.developer.username.myapp/**

    • template - defaults to 'default' which is a symlink to ubuntu-sdk. See aa-easyprof --policy-vendor=ubuntu --policy-version=1.0 --list-templates (using the appropriate vendor version) for a list of other templates

    • template_variables - the Ubuntu templates support setting the following variables:

      • APPNAME - typically the reverse domain (eg, com.ubuntu.developer.username.appname)

      • APPVERSION - application version

      These are used to differentiate application paths. Eg, the resulting AppArmor policy will have something like:

       @{APPNAME}="com.ubuntu.developer.username.myapp"
       @{APPVERSION}="0.1"
       ...
         /opt/click.ubuntu.com/@{APPNAME}/@{APPVERSION}/    r,
         /opt/click.ubuntu.com/@{APPNAME}/@{APPVERSION}/**  r,
         /opt/click.ubuntu.com/@{APPNAME}/@{APPVERSION}/**/ r,
    • policy_groups - these are used to grant permissions to the app, such as networking, online accounts, content picking, etc. Some policy groups might always be used (and therefore pre-filled), such as qmlscene while others will only be used by some apps (eg, qmlscene-webview for HTML5 apps). See aa-easyprof --policy-vendor=ubuntu --policy-version=1.0 --list-policy-groups for a complete list

  • Unused/ignored
    • name
    • author
    • comment
    • copyright
  • Red-flagged for manual review (use should actively be discouraged with updates made to policy groups and templates)
    • abstractions
    • read_path
    • write_path

Traditional packaging

Traditional packaging can also leverage aa-easyprof, but the process is slightly more involved. In general, the following need to happen (see man dh_apparmor for details):

  • the manifest file (only the security section is needed) is added to debian/. Because traditional packaging has different governance rules for including in a distribution, the manifest may contain any of the supported fields
  • aa-easyprof is given the manifest file to generate a profile
  • the profile is installed into a package
  • the postinst loads the AppArmor policy into the kernel

The process is made easier with dh_apparmor. Create a manifest file following the above instructions then:

  1. put the manifest file in debian/manifest.json
  2. adjust debian/control to Build-Depends on dh-apparmor >= 2.8.0-0ubuntu14

  3. update debian/rules to call dh_apparmor. Eg:

    override_dh_install:
            dh_apparmor -p<deb binary> --profile-name=<profile name from the manifest> --manifest=manifest.json
            dh_install

    and then to clean up:

    override_dh_clean:
            dh_clean
            rm -rf debian/apparmor
  4. install the files. Eg, add to debian/<deb binary>.install:

    debian/apparmor/<profile name> etc/apparmor.d

The remaining consideration is making sure that the app runs confined. You'll know you have it right if when the application is running, the output of aa-status shows that the application is confined. If the application provides an executable (eg, ELF binary, executable python script), then specifying the 'binary' in the manifest is enough. If instead a helper such as qmlscene is being used, there are several choices:

  • use the new Ubuntu application lifecycle and start the application via an Upstart job (preferred, pending but not available as of 2013/07/02)
  • add XCanonicalAppArmorProfile=<profile name> to the .desktop file until Ubuntu application lifecycle is finished (not available as of 2013/07/02)

  • update the .desktop file so use aa-exec -p <profile name> ... in the Exec line. Unfortunately there is an issue using aa-exec in .desktop files, which may be related to glib

  • Create a shell script to use aa-exec -p <profile name> ... and have the .desktop file use Exec=<path to shell script>

Bugs

When filing bugs dealing with the manifest file or resulting permissions, please use one of the below and use the 'application-confinement' tag:

SecurityTeam/Specifications/ApplicationConfinement/Manifest (last edited 2014-03-17 13:57:55 by jdstrand)