[FE training-materials-updates] slides/buildroot-new-packages: new slide about the hash file

[Thomas Petazzoni]

Repository : git://git.free-electrons.com/training-materials.git
On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=fb1f2e2d9fc7c1e5652b405c83de4e6b708830aa

>---------------------------------------------------------------

commit fb1f2e2d9fc7c1e5652b405c83de4e6b708830aa
Author: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Date:   Wed Jun 8 12:02:34 2016 +0200

    slides/buildroot-new-packages: new slide about the hash file
    
    Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>


>---------------------------------------------------------------

fb1f2e2d9fc7c1e5652b405c83de4e6b708830aa
 .../buildroot-new-packages.tex                     | 39 ++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/slides/buildroot-new-packages/buildroot-new-packages.tex b/slides/buildroot-new-packages/buildroot-new-packages.tex
index 4ecb5e2..465fc3d 100644
--- a/slides/buildroot-new-packages/buildroot-new-packages.tex
+++ b/slides/buildroot-new-packages/buildroot-new-packages.tex
@@ -591,6 +591,45 @@ PERL_EXTRA_DOWNLOADS = $(PERL_CROSS_SITE)/$(PERL_CROSS_SOURCE)
   \end{itemize}
 \end{frame}
 
+\begin{frame}[fragile]{Hash file}
+
+  \begin{itemize}
+
+  \item In order to validate the integrity of downloaded files, and
+    make sure the user uses the version which was tested by the
+    Buildroot developers, {\em cryptographic hashes} are used
+
+  \item Each package may contain a file named \code{<package>.hash},
+    which gives the hashes of the files downloaded by the package.
+
+  \item When present, the hashes for {\bf all} files downloaded by the
+    package must be documented.
+
+  \item The syntax of the file is:
+\begin{block}{}
+{\tiny
+\begin{verbatim}
+<hashtype> <hash> <file>
+\end{verbatim}
+}
+\end{block}
+
+  \item Example:
+
+\begin{block}{}
+{\tiny
+\begin{verbatim}
+# Locally computed
+sha256 2ee80bd0634a61a...3530396cccc09 unionfs-1.0.tar.gz
+sha256 c8526f80448f344...03bcd713d9de2 0001-include-asm-ioctl.h-for-_IOC_SIZE.patch
+\end{verbatim}
+}
+\end{block}
+
+  \end{itemize}
+
+\end{frame}
+
 \begin{frame}[fragile]{Describing dependencies}
   \begin{itemize}
   \item Dependencies expressed in \code{Config.in} do not enforce