Commit Graph

53 Commits

Author SHA1 Message Date
Robert Lubos
5cefcf80e9 net: sockets: Move offloading out of experimental
Socket offloading has been in the tree for a while and improved a lot
over time (from a simple define-based API override to a complex
vtable-based solution, supporting mutliple offloaded interfaces). As the
feature is heavily used by certain vendors (Nordic and its nRF Connect
SDK), I propose to move it out of experimental phase.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2022-05-06 11:30:22 +02:00
Robert Lubos
7ad2e604bb net: sockets: tls: Add options to control session caching on a socket
Introduce TLS socket options, which allow to configure session caching
on a socket.

The cache can be enabled on a socket with TLS_SESSION_CACHE option.
Once cache is enabled on a socket, the session will be stored for re-use
after a sucessfull handshake. If a socket is attempting to connect to a
host for which session is stored, the session will be resumed and mbed
TLS will attempt to use a simplified handshake procedure.
The server-side management of sessions is fully controlled by mbed TLS
after session caching is enabled on a socket.

The other TLS_SESSION_CACHE_PURGE option allows to clear all of the
cache entries, releasing the memory allocated for sessions.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2022-04-28 11:31:07 +02:00
Robert Lubos
e2fe8e7307 net: socket: Add option to create native TLS sock with offloaded TCP
In some cases (for examples when offloaded socket implementation does
not implement TLS functionality) it could be desired to create a native
TLS socket with an underlying offloaded socket.

This cannot be achieved with SO_BINDTODEVICE option only, as TLS socket
type is not really associated with a particular interface - it either
has to be offloaded, or a fully native socket is created (native TLS on
a native interface).

In order to address the problem, introduce TLS_NATIVE socket option.
This option instructs the socket dispatcher layer to create a native TLS
socket. As with the socket dispatcher the underlying socket
implementation is not decided during TLS socket creation, therefore it's
possible to use SO_BINDTODEVICE to choose either native or offloaded
interface for the underlying socket.

Additionally remove NET_SOCKETS_OFFLOAD_TLS Kconfig option, as it's no
longer needed with an runtime option to select whether to offload TLS or
not.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2022-04-20 11:27:05 +02:00
Robert Lubos
641b2a0d93 net: sockets: Add socket dispatcher
Add an intermediate socket implementation called socket dispatcher. This
layer can be used along with the socket offloading, to postpone the
actual socket creation until a first operation on a socket is executed.

This approach leaves an opening to bind a socket to a particular
offloaded network interface, and thus offloaded socket implementation,
using SO_BINDTODEVICE socket option. Thanks to this, it is now possible
to use multiple offloaded sockets implementations along with native
sockets, and easily select which socket should use with network
interface (even if it's an offloaded interface).

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2022-04-20 11:27:05 +02:00
Marcin Niestroj
cf75f01a71 net: sockets: introduce NET_SOCKETS_OFFLOAD_PRIORITY option
This option will be used as default socket priority by offloaded socket
drivers.

Describe how to prioritize native TLS over offloaded TLS (and vice
versa) using sockets priorities.

Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
2022-04-08 15:50:11 -07:00
Nazar Kazakov
f483b1bc4c everywhere: fix typos
Fix a lot of typos

Signed-off-by: Nazar Kazakov <nazar.kazakov.work@gmail.com>
2022-03-18 13:24:08 -04:00
Gerard Marull-Paretas
95fb0ded6b kconfig: remove Enable from boolean prompts
According to Kconfig guidelines, boolean prompts must not start with
"Enable...". The following command has been used to automate the changes
in this patch:

sed -i "s/bool \"[Ee]nables\? \(\w\)/bool \"\U\1/g" **/Kconfig*

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
2022-03-09 15:35:54 +01:00
Torsten Rasmussen
36f5600387 kconfig: net: experimental settings now uses select EXPERIMENTAL
With the introduction of `EXPERIMENTAL` and `WARN_EXPERIMENTAL` in
Zephyr all subsys/net and drivers/ethernet/Kconfig.e1000 settings
having `[EXPERIMENTAL]` in their prompt has has been updated to include
`select EXPERIMENTAL` so that developers can enable warnings when
experimental features are enabled.

The following settings has EXPERIMENTAL removed as they are considered
mature:
- NET_OFFLOAD
- NET_PROMISCUOUS_MODE

Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
2021-10-25 10:46:48 +02:00
Robert Lubos
0dbdcc770d net: sockets: Add socket processing priority
When creating a socket, all of the registered socket implementation are
processed in a sequence, allowing to find appropriate socket
implementation for specified family/type/protocol. So far however,
the order of processing was not clearly defined, leaving ambiguity if
multiple implmentations supported the same set of parameters.

Fix this, by registering socket priority along with implementation. This
makes the processing order of particular socket implementations
explicit, giving more flexibility to the user, for example when it's
neeed to prioritze one implementation over another if they support the
same set of parameters.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2021-09-28 20:11:26 -04:00
Paul Sokolovsky
471afe5ddc net: sockets: Make NET_SOCKETS_POSIX_NAMES be on by default
Zephyr socket subsystem has come a long way since initial experimental
alternative to internal Zephyr networking API. Its configuration also
mirrors the usual conservative approach, where a user needs to
explicitly enable options to get "more" features. And as an
experimental API, socket subsystem was initially developed as
namespaced API, where all functions/structures are prefixed with
"zsock_", and to get standard names, CONFIG_NET_SOCKETS_POSIX_NAMES
needs to be set (or alternatively, CONFIG_POSIX_API needs to be, which
enabled full POSIX subsys overall).

However, a few years later, sockets are the standard networking API,
and in majority of cases its used under the standard POSIX names.
Necessity to explicitly set an option to achieve this effects, and
confusion which results from it - are just unneeded chores for users.

So, switch CONFIG_NET_SOCKETS_POSIX_NAMES to be on by default (unless
CONFIG_POSIX_API is already defined). It still can be explicitly
disabled if needed (but usecases for that would be peculiar and rare).

Addresses #34165

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
2021-04-13 13:00:53 -04:00
Jani Hirsimäki
bd40cb48d9 net: socket: packet: using pckt sckt for passing the PPP dialup data
With these changes, dial up Zephyr application/driver can use
socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW) for creating
a socket for sending/receiving data to/from ppp net link, i.e.
packet is going to/from PPP L2.

Signed-off-by: Jani Hirsimäki <jani.hirsimaki@nordicsemi.no>
2021-04-01 09:43:56 +03:00
Marcin Niestroj
fbc487cce3 net: tls: use Maximum Fragment Length (MFL) extension by default
Call mbedtls_ssl_conf_max_frag_len() on created TLS context
configuration, so that Maximum Fragment Length (MFL) will be sent to
peer using RFC 6066 max_fragment_length extension. MFL value is
automatically chosen based on MBEDTLS_SSL_OUT_CONTENT_LEN and
MBEDTLS_SSL_IN_CONTENT_LEN mbed TLS macros.

This extension is mostly useful for TLS client side to tell TLS server
what is the maximum supported receive record length.

Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
2020-11-05 14:47:24 +02:00
Emil Hammarstrom
ec00feef35 net: lib: sockets: added ALPN extension option to TLS
Adds the socket option TLS_ALPN_LIST for SOL_TLS sockets

Passes the configured alpn list to the mbedtls config
on mbedtls init

Signed-off-by: Emil Hammarstrom <emil.hammarstrom@assaabloy.com>
2020-10-22 11:35:43 +03:00
Robert Lubos
b79f538adc net: sockets: tls: Add Kconfig option to disable offloaded TLS
This new option allows to include `sockets_tls.c` into the build when
socket offloading is enabled.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2020-09-03 11:00:01 +03:00
Jukka Rissanen
2ba4d5c2f0 net: socket: packet: Add support to SOCK_DGRAM packet sockets
Allow user to create SOCK_DGRAM type AF_PACKET socket. This
allows user to send raw IP packets without specifying
L2 (like Ethernet) headers.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2020-08-27 10:56:06 +03:00
Adam Porter
f09b8681f6 net: sockets: remove POSIX_NAMES dependency on SOCKETS_OFFLOAD
This is no longer required since drivers implementing the sockets
offload interface were migrated to use pure zsock_ instead of
raw POSIX types and functions.

Signed-off-by: Adam Porter <porter.adam@gmail.com>
2020-06-17 08:55:17 +03:00
Christopher Friedt
09f957c47a net: socket: syscall for socketpair(2)
Working:

* non-blocking reads / writes
* blocking reads / writes
* send(2) / recv(2) / sendto(2) / recvfrom(2) / sendmsg(2)
* select(2)
* poll(2)

Fixes #24366

Signed-off-by: Christopher Friedt <chrisfriedt@gmail.com>
2020-05-10 17:46:43 +02:00
Vincent Wan
115949a97f sockets: tls: set TLS_CREDENTIALS when using non-native stack
When is NET_SOCKETS_SOCKOPT_TLS set, it should set TLS_CREDENTIALS
even when NET_NATIVE=n, so that platforms that use socket offloading
can continue to set TLS credentials.

We are now setting this via 'imply' instead of 'select', so that
prj.conf can opt out if necessary.

Fixes #22390

Signed-off-by: Vincent Wan <vincent.wan@linaro.org>
2020-02-05 18:47:54 -05:00
Robert Lubos
41cfe0b31a sockets: tls: Fix Kconfig mbedTLS dependencies
Sort out mbedTLS dependencies in sockets Kconfig. mbedTLS will now
be enabled when TLS sockets and native network stack are enabled.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2020-01-31 09:52:21 +02:00
Ulf Magnusson
bd6e04411e kconfig: Clean up header comments and make them consistent
Use this short header style in all Kconfig files:

    # <description>

    # <copyright>
    # <license>

    ...

Also change all <description>s from

    # Kconfig[.extension] - Foo-related options

to just

    # Foo-related options

It's clear enough that it's about Kconfig.

The <description> cleanup was done with this command, along with some
manual cleanup (big letter at the start, etc.)

    git ls-files '*Kconfig*' | \
        xargs sed -i -E '1 s/#\s*Kconfig[\w.-]*\s*-\s*/# /'

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
2019-11-04 17:31:27 -05:00
Ulf Magnusson
975de21858 kconfig: Global whitespace/consistency cleanup
Clean up space errors and use a consistent style throughout the Kconfig
files. This makes reading the Kconfig files more distraction-free, helps
with grepping, and encourages the same style getting copied around
everywhere (meaning another pass hopefully won't be needed).

Go for the most common style:

 - Indent properties with a single tab, including for choices.

   Properties on choices work exactly the same syntactically as
   properties on symbols, so not sure how the no-indentation thing
   happened.

 - Indent help texts with a tab followed by two spaces

 - Put a space between 'config' and the symbol name, not a tab. This
   also helps when grepping for definitions.

 - Do '# A comment' instead of '#A comment'

I tweaked Kconfiglib a bit to find most of the stuff.

Some help texts were reflowed to 79 columns with 'gq' in Vim as well,
though not all, because I was afraid I'd accidentally mess up
formatting.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
2019-11-01 15:53:23 +01:00
David B. Kinder
241044f178 doc: fix misspellings in Kconfig files
Fix misspellings in Kconfig files missed during regular reviews.

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
2019-10-30 10:24:30 +01:00
Alexander Wachter
c8c5f3bbf3 net: canbus: Rename canbus to canbus_raw
Rename the socket_can implementation from CANBUS to CANBUS_RAW.
This is a preperation for 6LoCAN which is a CANBUS L2 for IPv6.

Signed-off-by: Alexander Wachter <alexander.wachter@student.tugraz.at>
2019-08-08 13:25:01 +03:00
Jukka Rissanen
c0d6831bc0 net: sockets: mgmt: Add AF_NET_MGMT address family support
Allow application to listen network management events using
BSD socket API. Application needs to create the socket using
AF_NET_MGMT address family. At this point we only support
receiving network management events that the network subsystem
is sending.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2019-07-01 13:50:08 -07:00
Ravi kumar Veeramally
84b191edd2 net: sockets: Add timeout to socket connect call
Current socket connect call implementation always takes
K_FOREVER timeout value, which blocks TCP connections
in case failure. TCP connections waits until it receives
SYN ACK. If there is no SYC ACK means, connect call is
blocked forever.

Added a Kconfig option to define timeout value. Default
value is 3000 milliseconds. User can modify it.

Signed-off-by: Ravi kumar Veeramally <ravikumar.veeramally@linux.intel.com>
2019-07-01 10:34:15 +03:00
Jukka Rissanen
6621491014 net: sockets: can: Add dispatcher
We need to dispatch the received CAN frame if there are multiple
sockets interested in the same CAN-IDs.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2019-06-18 17:58:00 +03:00
Paul Sokolovsky
0fb8a917e6 net: sockets: Make NET_SOCKETS_POSIX_NAMES depend on !POSIX_API
These options are mutually exclusive, or more specifically,
CONFIG_POSIX_API has wider scope and supersedes
CONFIG_NET_SOCKETS_POSIX_NAMES. Implementation-wise, the two
options should not be defined at the same time, as that may
lead to declaration conflicts.

Fixes: #16141

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
2019-06-05 07:51:01 -04:00
Jukka Rissanen
1897896e97 net: sockets: Make sure that getaddrinfo() cannot hang forever
If for some reason the DNS resolver callback is not called properly
then make sure that semaphore will not block forever.

Fixes #15197

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2019-04-11 18:01:08 -04:00
Jukka Rissanen
c1d5cc26c1 net: sockets: Remove extra "default n" setting from config
No need to say "default n" as that is the implicit default.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2019-02-08 16:01:49 +02:00
Jukka Rissanen
f610db9453 net: l2: Add CANBUS L2 layer
This is basically a dummy layer that just passes data through.
It is needed so that we can create CANBUS type network interface
to the system.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2019-02-07 18:08:27 +02:00
Jukka Rissanen
49cea0a199 net: socket: can: Add socket CAN support
This allows user to create a CAN socket and to read/write data
from it. From the user point of view, the BSD socket CAN support
works same way as in Linux.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2019-02-07 18:08:27 +02:00
Ravi kumar Veeramally
a9a2b3ea91 net: sockets: Add socket api to support AF_PACKET
This commit adds packet socket support to socket api.
This version supports basic packet socket features.
Protocol family is AF_PACKET, type of socket is
SOCK_RAW and proto type is ETH_P_ALL. The user will
receive every packet (with L2 header) on the wire.
For TX, the subsystem expects that the user has set
all the protocol headers (L2 and L3) properly.

Networking subsystem doesn't verify or alter the headers while
sending or receiving the packets. This version supports packet
socket over Etherent only. Also combination of other family
and protocols doesn't work (i.e. Application can not open
packet-socket and non packet-socket together).

Signed-off-by: Ravi kumar Veeramally <ravikumar.veeramally@linux.intel.com>
2019-02-07 14:43:30 +02:00
Robert Lubos
e8620e2cca ext: mbedtls: Unify mbedTLS Kconfig prefixes
Currently there is a mixed approach in prefixes from mbedTLS
configuration (MBEDTLS_ and TLS_). The latter was used in generic config
file and could bring up confusion that it can only be used with TLS
subsystem. Hence unify the approach to MBEDTLS_ prefix to avoid such
confusion.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-12-17 11:27:02 +01:00
Jukka Rissanen
009e4dafa7 net: Make Kconfig template variables prettier
Adding spaces around "=" when definining Kconfig template so
that is more consistent with overall style of these template
variables.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2018-10-05 09:01:37 -04:00
Jukka Rissanen
dc29ed0bd9 net: lib: Convert socket library to use log level
Use network log level in BSD socket library.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2018-10-04 14:13:57 +03:00
Gil Pitney
c21b0fb357 net: sockets: Add a socket offload module
This patch enables BSD socket offload to a dedicated
TCP/IP offload engine.

This provides a simpler, more direct mechanism than going
through NET_OFFLOAD (zsock -> net_context -> socket conversions)
for those devices which provide complete TCP/IP offload at the
BSD socket level, and whose use cases do not require
IP routing between multiple network interfaces.

To use, configure CONFIG_NET_SOCKETS_OFFLOAD=y, and register
socket_offload_ops with this module.

Fixes #3706

Signed-off-by: Gil Pitney <gil.pitney@linaro.org>
2018-09-11 18:42:34 +03:00
Robert Lubos
8697cc946f net: tls: Add timeout for mbetTLS read
Specify timeout value for mbedtls_ssl_read function for DTLS servers.
Adding this can prevent TLS context lockup in case blocking recv is used
and peer has shut down DTLS connection without closing it gracefully.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-08-13 15:24:34 +03:00
Robert Lubos
85db974ec3 net: tls: Add DTLS protocol types
Define DTLS protocol types and and Kconfig option to enable DTLS
support.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-08-13 15:24:34 +03:00
Ulf Magnusson
d1684a83a4 Kconfig: Clean up some symbol definitions
- Remove redundant 'n' defaults. 'n' is the default value for bool
  symbols.

  This makes the auto-generated documentation clearer as well: You get
  "implicitly defaults to n" instead of
  "- n if <propagated dependencies>".

- Shorten

      <type>
      prompt "foo"

  to

      <type> "foo"

  This works for all types, not just bool.

- Various formatting nits.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
2018-08-01 12:47:17 -04:00
Robert Lubos
11c24c855d net: tls: Add socket option to select ciphersuites
Add TLS secure socket option that enables to narrow list of ciphersuites
available for TLS connection.

This option accepts an array of integers with IANA assigned ciphersuite
identifiers and returns such.

By default, every statically configured ciphersuite is available for a
socket and getsockopt returns an array of these.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-07-26 12:13:15 -04:00
Robert Lubos
48e055577b net: tls: Add socket option to select TLS credentials
Add TLS secure socket option to select TLS credentials to use.

This option accepts and returns an array of sec_tag_t that indicate
which TLS credentials should be used with specific socket.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-07-26 12:13:15 -04:00
Robert Lubos
d09cbcaf6f net: tls: Add credential management subsystem
Add TLS credential management subsystem that enables to register TLS
credentials in the system. Once specific credentials are registered in
the system, they will be available for TLS secure sockets to use.

To use a TLS credential with a socket, the following steps have to be
taken:
1. TLS credential has to be registered in a system-wide pool, using the
API provided in "net/tls_credentials.h" header file.
2. TLS credential (and other TLS parameters) should be set on a socket
using setsockopt().

Note, that there is no need to repeat step 1 for different sockets using
the same credentials. Once TLS credential is registered in the system,
it can be used with mulitple sockets, as long as it's not deleted.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-07-26 12:13:15 -04:00
Robert Lubos
a7c698d936 net: tls: Add TLS context allocation/deallocation
Add tls_context structure that stored data required by TLS socket
implementation. This structure is allocated from global pool during
socket creation and freed during socket closure.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-07-13 15:03:45 -04:00
Robert Lubos
00a69bf9bb net: socket: Add switch to enable TLS socket option support
Add switch to a socket layer that will enable switching socket API to
TLS secure sockets. At this point there is no secure sockets
implementation, so secure socket calls redirect to regular socket calls.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
2018-07-13 15:03:45 -04:00
Ulf Magnusson
1073882998 subsys: kconfig: Remove 'default n' properties and clean up a bit
Bool symbols implicitly default to 'n'.

A 'default n' can make sense e.g. in a Kconfig.defconfig file, if you
want to override a 'default y' on the base definition of the symbol. It
isn't used like that on any of these symbols though.

Remove some 'default ""' properties on string symbols too.

Also make definitions more consistent by converting some

  config FOO
  	<type>
  	prompt "foo"

definitions to a shorter form:

  config FOO
  	<type> "foo"

This shorthand works for int/hex/string symbols too, not just for bool
symbols.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
2018-07-12 23:13:22 -04:00
Anas Nashif
429c2a4d9d kconfig: fix help syntax and add spaces
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-13 17:43:28 -06:00
Paul Sokolovsky
c7da45f9e2 net: Enable logging in more modules if CONFIG_NET_LOG_GLOBAL defined
This is useful to enable error/warning logging across the net
codebase (less useful for debug level logging, but that's true
for CONFIG_NET_LOG_GLOBAL already).

Implementation-wise, instead of keeping adding to long list of
"select"'s in CONFIG_NET_LOG_GLOBAL and thus introduce component
inter-dependencies, add "default y if NET_LOG_GLOBAL" to
individual components' logging options.

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
2017-09-18 08:19:27 -04:00
Paul Sokolovsky
d9af77bfd6 net: sockets: Consistently use "BSD Sockets compatible API" moniker
This is how it's called in the main docs, so use this same phrase in
Kconfig and samples too.

Also, added some articles to docs.

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
2017-08-17 12:02:55 -05:00
David B. Kinder
81f7c82625 doc: fix misspellings and missing EOF newlines
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
2017-08-16 17:38:41 -05:00
David B. Kinder
62a0cd246d doc: fix uses of back quotes in documentation
ReST defines interpreted text roles where text enclosed by single quotes
can be "intrepreted", for example :ref:`some name` becomes a link to
a label anywhere in the doc set named "some name", :c:func:`funcname()`
becomes a link to the API documentation for "funcname", and
:option:`CONFIG_NAME` becomes a link to, in our case, the documentation
for the generated Kconfig option.

This patch fixes uses of `some name` (without a role) by either adding
an explicit role, or changing to ``some name``, which indicates inline
code block formatting (most likely what was intended).

This is a precursor to changing the default behavior of interpreted
text to treat `some name` as :any:`some name` (as configured in
doc/conf.py), which would attempt to create a link to any available
definition of "some name".

We may not change this default role behavior, but it becomes an option
after the fixes in this patch.  In any case, this patch fixes incorrect
uses of single-quoted text (possibly introduced because GitHub's
markdown language uses single-quoted text for inline code formatting).

Jira: ZEP-2414

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
2017-08-03 11:08:23 -04:00