[sf-lug] 2019-08-04 meeting notes, about WRT54G* 3rd party router firmware

Mon Aug 5 14:25:09 PDT 2019

Aaron,

Very comprehensive response.

John

Sent from my iPad

> On Aug 5, 2019, at 10:16 AM, aaronco36 <aaronco36 at sdf.org> wrote:
> 
> Bobbie Sellers <bliss-sf4ever at dslextreme.com> wrote in [01]
>> Aaron came in with a couple of routers and took one or more away
>> including I think the book on programming them.
>> 
>> About 12:20 Jim Stockford showed up.
> 
> Not at all to Steal any of Charlie's Fire in his discussion of his vast IT experience "of over 35 years in Silicon valley" (see reference [02]), but I'd add that there were also a few mini-discussions regarding the WRT54G* routers (see reference [03]) that John S graciously donated to several of us meeting participants.
> IIRC, the three WRT54G* routers models were
> - the WRT54GLv1.1 (see its full WikiDevi description at reference [04])
> - the WRT54Gv2.2 (see its full WikiDevi description at reference [05])
> - the WRT54Gv3.1 (see its full WikiDevi description at reference [06])
> 
> I took the WRT54GLv1.1 without an included power adapter, Jim S took the WRT54Gv2.2 _with_ its included power adapter, and Adell (if that's the correct spelling of his name) took the WRT54Gv3.1 also with its included power adapter.  Going back to the previous mailing-list threads of about a year-and-a-third ago of [07] and [08] concerning various consumer-router firmware, all three of these WRT54G* routers had 4 MiB flash and 16 MiB RAM.  A practical import of these routers' flash and RAM limitations is that current versions of OpenWRT may not function adequately on these routers as per the OpenWrt's ominous-sounding "4/32 warning" in reference [09].
> Directly quoting that OpenWRT 4/32 warning page....
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Every operating system requires
> 
>    1. Sufficient Flash to accommodate firmware image
>    2. Sufficient RAM for stable operation
> 
> ((!)) Devices with 4MB flash and/or 32MB ram will work but they will be very limited (usually they can't install or run additional packages) because they have low RAM and flash space. Consider this when choosing a device to buy, or when deciding to flash OpenWrt on your device because it is listed as supported.
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> Also see the 4/32 warning page's sections "Usability issues;Insufficient RAM for stable operation" and "Extensibility issues;Barely enough Flash to accommodate OpenWrt firmware image".
> 
> The point from OpenWrt's 4/32 warning is that current and future versions of its firmware are discouraged for use on WRT54G* routers such as these which have 4 MiB flash and 16 MiB RAM, at least for most users anyway. Better firmware for these routers, subjectively-speaking, could possibly be DD-WRT and Tomato firmware, which according to at least references [10],[11] and [12] (besides within the routers' aforementioned WikiDevi descriptions at [04],[05],[06]) are all well-supported on these WRT54G* routers.
> 
> OTOH, Rick M wrote within his prior posting at [13]:
> 
>> Remember:  Whether vulnerabiities in old software matters depends
>> in part on what features are enabled in the local installation.
>> E.g., I routinely skim-read CVEs about kernel bugs and judge them
>> to be irrelevant to my system because they're flaws in
>> drivers/subsystems not present on my systems.
>> While I doubt any 2.4.x kernels are still safe today, I'll bet
>> many 2.6.x kernels are, particularly ones for which the local admin
>> has locked down what is enabled (and more so ones compiled locally
>> to build only what is needed, though few admins bother to do so any
>> more).
> 
> And DD-WRT's K26 Build Supported Router List for its 2.6.x kernel firmware in reference [14] specifically _excludes_ all three of these WRT54G* routers. Which possibly/probably means that _few_ of DD-WRT's 2.4.x kernels in its K24 builds are deemed to be "still safe today" :-\
> 
> So for most users, this could very well be a tradeoff between having to use older OpenWrt firmware that is just able to fit on these WRT54G* routers vs. using one of DD-WRT's potentially "unsafe" K24 builds.
> 
> Further router firmware questions remain.
> E.g.,
> - How far back does one have to go to obtain sufficient OpenWrt firmware for these routers?
> - Given the OpenWrt Release Archive list of [15], will LEDE 17.01.x firmware function appropriately on these three WRT54G* routers? How about the same for either Chaos Calmer 15.05x, Barrier Breaker 14.07, Attitude Adjustment 12.09, Backfire 10.03x, or even earlier??
> - If a DD-WRT K24 build (with its mandatory 2.4.x kernel) is preferable, then which numbered build is best, even it's not necessarily the latest and highest-numbered build?
> - And which specific DD-WRT V24_pre_sp2 K24 build listed within the chart at reference [16] is best for a particular WRT54G* device, from the below handful of options with their numerous pick-n-choose set of features??
> -- dd-wrt.v24_micro, a.k.a. "Micro"
> -- dd-wrt.v24_mini, a.k.a. "Mini"
> -- dd-wrt.v24_std, a.k.a. "STD"
> -- dd-wrt.v24_voip, a.k.a. "VOIP"
> -- dd-wrt.v24_vpn, a.k.a. "VPN"
> 
> 
> Rick M, Michael P, Bobbie S, and anyone else reading are all welcome to jump in here with your opinions, suggestions, background info, website referrals, .... etcetera.
> 
> -A
> 
> 
> ==========================================
> REFERENCES:
> ==========================================
> [01]http://linuxmafia.com/pipermail/sf-lug/2019q3/014293.html
> [02]https://www.openrefactory.com/
> [03]http://linuxmafia.com/pipermail/sf-lug/2019q3/014284.html
> [04]https://wikidevi.com/wiki/Linksys_WRT54GL_v1.1
> [05]https://wikidevi.com/wiki/Linksys_WRT54G_v2.2
> [06]https://wikidevi.com/wiki/Linksys_WRT54G_v3.1
> [07]http://linuxmafia.com/pipermail/sf-lug/2018q2/013161.html
> [08]http://linuxmafia.com/pipermail/sf-lug/2018q2/013163.html
> [09]https://openwrt.org/supported_devices/432_warning
> [10]https://wiki.dd-wrt.com/wiki/index.php/Linksys_WRT54G/GL/GS/GX
> [11]https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=51486
> [12]https://wikidevi.com/wiki/List_of_Tomato_firmware_supported_devices
> [13]http://linuxmafia.com/pipermail/sf-lug/2018q2/013153.html
> [14]https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=63757
> [15]https://downloads.openwrt.org/
> [16]https://forum.dd-wrt.com/wiki/index.php/What_is_DD-WRT%3F#File_Versions
> ==========================================
> 
> aaronco36 at sdf.org
> ---
> 
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