[dpdk-dev] [PATCH 5/5] doc: extend installation section on SNOW3G/KASUMI PMDs

[Pablo de Lara <pablo.de.lara.guarch@intel.com>]

SNOW3G and KASUMI SW libraries encrypt buffers
assuming that they are padded to a specific block size.
This behaviour can be changed to avoid buffer overflow,
by modifying the Makefile of these libraries.
Therefore, the Installation section in the SNOW3G and
KASUMI documentation has been extended, to document
this case.

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
---
 doc/guides/cryptodevs/kasumi.rst | 12 ++++++++++++
 doc/guides/cryptodevs/snow3g.rst | 11 +++++++++++
 2 files changed, 23 insertions(+)

diff --git a/doc/guides/cryptodevs/kasumi.rst b/doc/guides/cryptodevs/kasumi.rst
index bff9321..738ecee 100644
--- a/doc/guides/cryptodevs/kasumi.rst
+++ b/doc/guides/cryptodevs/kasumi.rst
@@ -70,6 +70,18 @@ on their system before building DPDK::
 
    make
 
+**Note**: When encrypting with KASUMI F8, by default the library
+encrypts full blocks of 8 bytes, regardless the number of bytes to
+be encrypted provided (which leads to a possible buffer overflow).
+To avoid this situation, it is necessary not to pass
+3GPP_SAFE_BUFFERS as a compilation flag.
+Also, this is required when using chained operations
+(cipher-then-auth/auth-then-cipher).
+For this, in the Makefile of the library, make sure that this flag
+is commented out::
+
+  #EXTRA_CFLAGS  += -D_3GPP_SAFE_BUFFERS
+
 **Note**: To build the PMD as a shared library, the libsso_kasumi
 library must be built as follows::
 
diff --git a/doc/guides/cryptodevs/snow3g.rst b/doc/guides/cryptodevs/snow3g.rst
index 12b6c4a..41c48d6 100644
--- a/doc/guides/cryptodevs/snow3g.rst
+++ b/doc/guides/cryptodevs/snow3g.rst
@@ -69,6 +69,17 @@ on their system before building DPDK::
 
    make snow3G
 
+**Note**: When encrypting with SNOW3G UEA2, by default the library
+encrypts blocks of 4 bytes, regardless the number of bytes to
+be encrypted provided (which leads to a possible buffer overflow).
+To avoid this situation, it is necessary not to pass
+3GPP_SAFE_BUFFERS as a compilation flag.
+For this, in the Makefile of the library, make sure that this flag
+is commented out.::
+
+  #EXTRA_CFLAGS  += -D_3GPP_SAFE_BUFFERS
+
+
 Initialization
 --------------
 
-- 
2.9.4