Adding CPEs for a few dependencies.

CPEs are the way that MITRE tracks different projects and versions, and
that's the input required by Vomit, Google's automated vulnerability
notification system. At present Vomit is unable to identify the versions
for these components and is therefore reporting the wrong CVEs in crbugs.

Adding this CPEPrefix line will enable Vomit to notify for any
vulnerabilities affecting these versions.

This is the first such change to README.chromium files. If successful,
CPEPrefix lines will be added to many others too.

Bug: 895969
Change-Id: Ibec5adf9069cdc20e40fb13658e7b056e938f5ce
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2053847
Reviewed-by: Charlie Reis <creis@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Adrian Taylor <adetaylor@chromium.org>
Auto-Submit: Adrian Taylor <adetaylor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#746237}

docs/adding_to_third_party.md

@@ -123,6 +123,24 @@ into the product and does any of the following:
 * Collects new data
 * Influences or sets security-related policy (including the user experience)
 
+One of the fields is CPEPrefix. This is used by Chromium and Google systems to
+spot known upstream security vulnerabilities, and ensure we merge the fixes
+into our third-party copy. These systems are not foolproof, so as the OWNER,
+it's up to you to keep an eye out rather than solely relying on these
+automated systems. But, adding CPEs decreases the chances of us missing
+vulnerabilities, so they should always be added if possible.
+
+The CPE is a common format shared across the industry; you can look up the CPE
+for your package [here](https://nvd.nist.gov/products/cpe/search). Please use
+CPE format 2.2. When searching for a CPE, you may find that there is not yet
+a CPE for the specific upstream version you're using. This is normal, as CPEs
+are typically allocated only when a vulnerability is found. You should follow
+the version number convention such that, when that does occur in future, we'll
+be notified. If no CPE is available, please specify "unknown".
+
+You may sometimes find that your package lacks a CPE, in which case this line
+can be omitted. If it does have a CPE, though, you should specify it.
+
 ### Add a LICENSE file and run related checks
 
 You need a LICENSE file. Example:

third_party/README.chromium.template

@@ -8,6 +8,7 @@ License: The license under which the package is distributed. Standard forms are
 License File: (OPTIONAL) File that contains a copy of the package's license. Use the special value NOT_SHIPPED to indicate that the package is not included in the shipped product, so its license does not need to be included in about:credits and no license file is required.
 Security Critical: Either yes or no depending on whether this package is shipped in releases. For example openssl is critical where cygwin is not.
 License Android Compatible: (OPTIONAL) Whether the package uses a license compatible with Android. Required only if the package is compatible and the 'License' field uses a non-standard value.
+CPEPrefix: (OPTIONAL) A 'common platform enumeration' version 2.2, as per https://nvd.nist.gov/products/cpe/search, which represents the upstream package. This will be used to report known vulnerabilities in the upstream software package, such that we can be sure to merge fixes for those vulnerabilities. Please ensure you're using the closest applicable upstream version, according to the standard format for the CPE for that package. For example, cpe:/a:xmlsoft:libxslt:1.0.10. If no CPE is available for the package, please specify "unknown".
 
 Description:
 A short description of what the package is and is used for.

third_party/expat/README.chromium

@@ -2,6 +2,7 @@ Name: Expat XML Parser
 Short Name: expat
 URL: https://github.com/libexpat/libexpat
 Version: R_2_2_9-45-g63abbcd
+CPEPrefix: cpe:/a:libexpat:expat:2.2.9
 Date: 20191122
 Revision: 63abbcdb3b743049bb3ee9e962a3280a3dad4191
 Security Critical: yes

third_party/harfbuzz-ng/README.chromium

@@ -2,6 +2,7 @@ Name: harfbuzz-ng
 Short Name: harfbuzz-ng
 URL: http://harfbuzz.org
 Version: 2.6.4-458
+CPEPrefix: cpe:/a:harfbuzz_project:harfbuzz:2.6.4
 Date: 20200206
 Revision: 63b8190db884d9ae88a80336067eab539a44b882
 Security Critical: yes

third_party/libpng/README.chromium

@@ -1,6 +1,7 @@
 Name: libpng
 URL: http://libpng.org/
 Version: 1.6.37
+CPEPrefix: cpe:/a:libpng:libpng:1.6.37
 Security Critical: yes
 License: libpng license
 License Android Compatible: yes

third_party/libvpx/README.chromium

@@ -1,6 +1,7 @@
 Name: libvpx
 URL: http://www.webmproject.org
 Version: v1.8.2
+CPEPrefix: cpe:/a:john_koleszar:libvpx:1.8.2
 License: BSD
 License File: source/libvpx/LICENSE
 Security Critical: yes

third_party/libxslt/README.chromium

@@ -1,6 +1,7 @@
 Name: libxslt
 URL: http://xmlsoft.org/XSLT
 Version: 3653123f992db24cec417d12600f4c67388025e3
+CPEPrefix: cpe:/a:xmlsoft:libxslt:1.1.34
 Security Critical: yes
 License: MIT
 License File: src/Copyright