[HN Gopher] GNU Radio 3.9
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       GNU Radio 3.9
        
       Author : lukastyrychtr
       Score  : 87 points
       Date   : 2021-01-18 16:29 UTC (6 hours ago)
        
 (HTM) web link (www.gnuradio.org)
 (TXT) w3m dump (www.gnuradio.org)
        
       | rsync wrote:
       | What is the current "easy" tooling/workup for GNU Radio ?
       | 
       | It used to be that you could download a GNU Radio livecd and that
       | worked well - however it is no longer maintained. The latest
       | release is from 2017 and I see it written that it is neither
       | supported nor recommended.
       | 
       | Is loading the distro of my choice and then managing and
       | installing GNU Radio, plus associated utilities/applications, and
       | their dependencies my only choice in 2021 ?
        
         | moftz wrote:
         | PyBOMBS is probably the best way if you want to be able to
         | handle out-of-tree modules. If you just want to play around
         | with the built-in functions, using a prebuilt binary from a
         | package repo is the easiest.
         | 
         | https://github.com/gnuradio/pybombs#pybombs
        
       | earthscienceman wrote:
       | A related note/question: why do projects like this choose github
       | over gitlab? It's become a weird world to me, where a GNU project
       | could ethically choose github.
       | 
       | To be clear, I use github often as well, but it seems odd to me
       | that a GNU sponsored project would.
        
         | Triv888 wrote:
         | They should at least push it to both (maybe blocking
         | issues/comments/etc on one of them).
        
         | [deleted]
        
         | hollimolli wrote:
         | gitlab is just another company; you probably mean a self-hosted
         | gitlab server?
        
       | [deleted]
        
       | superkuh wrote:
       | I have a physical box for each minor version of GNU Radio;
       | working installs of 3.6 to 3.8. I doubt I'll be moving anything
       | major to 3.9 any time soon.
       | 
       | Unrelated, I wish the gnuradio website would have HTTP and HTTPS.
       | HTTPS only is pretty restrictive and not relevant in the context.
        
         | jimktrains2 wrote:
         | > HTTPS only is pretty restrictive and not relevant in the
         | context.
         | 
         | This seems even more off-topic than complaining about the
         | readability of a site's style. How is HTTPS restrictive and how
         | does context outside of "being a website" make HTTPS excessive?
        
           | superkuh wrote:
           | When older systems try to access an HTTPS only site they get
           | blocked because there's no cypher overlap or no copies of the
           | cert authority's new root cert (ie, LetsEncrypt's new one).
           | Everyone realized just how much of a problem this was at the
           | start of the pandemic when millions couldn't access HTTPS
           | only government information sources and sites rolled back
           | their security theater.
           | 
           | It's trading accessibility to cargo-cult security.
        
             | cogman10 wrote:
             | I've never heard of HTTPS being described as security
             | theater.
             | 
             | What are the issues with TLS 1.3 that make it insecure or
             | ineffectual?
        
               | superkuh wrote:
               | It's security theater in the contex of HTTPS _only_ on
               | websites that aren 't performing financial transactions.
               | The idea that someone _might_ figure out a way to do a
               | TLS downgrade attack and force someone over to the HTTP
               | site is not justification for HTTPS only in those cases.
               | 
               | I love TLS. I think it's the least worst system we have.
               | But HTTPS _only_ outside of it 's proper context does a
               | lot of harm and it's pointless. HTTP and HTTPS are two
               | great tastes that go great together.
        
               | MrRadar wrote:
               | HTTPS-only is valuable for three reasons. Firstly it
               | prevents MITM attacks that inject Javascript (or other)
               | payloads into web pages which can be used e.g. for DDoS
               | attacks. We saw this with the Great Firewall being used
               | to attack Github for hosting material that was censored
               | in China by hijacking an analytics script that was being
               | served over HTTP[1].
               | 
               | Secondly, it makes passive surveillance and data
               | gathering much harder. You can still track which sites a
               | user connects to, but you can't see which pages they
               | access or the contents of those pages. You can still
               | actively intercept those connections via MitM but that
               | requires users to manually install an MitM certificate on
               | their system so they should be aware when it's occurring.
               | 
               | Thirdly, it makes it harder to intentionally block or
               | break HTTPS altogether at the network level to force
               | users to fall back to unencrypted HTTP. (TLS downgrade
               | attacks are different from and much more difficult than,
               | for example, just blocking all traffic on port 443.) If
               | there's no unencrypted fallback, then users will complain
               | loudly when they can't access sites.
               | 
               | If your main concern is old computers the solution is to
               | use a proxy that strips the encryption.
               | 
               | [1] https://www.bankinfosecurity.com/github-hit-by-its-
               | largest-d...
        
               | apple_innocent wrote:
               | "If your main concern is old computers the solution is to
               | use a proxy that strips the encryption."
               | 
               | Why not also use the proxy to add encryption when it is
               | missing. Then "HTTPS-only" is not necessary. The decision
               | of which scheme to use, http:// or https://, rests with
               | the user, not the server.
        
               | MrRadar wrote:
               | Encrypting data _after_ it has transited untrustworthy
               | networks (which could have surveilled or modified it
               | before it gets to you) is about as useful as closing the
               | barn door after the horse has already escaped. The
               | encryption (and authentication) needs to happen at the
               | origin to get any security benefit.
        
               | eesmith wrote:
               | http://n-gate.com/software/2017/ gives some pointers.
               | I'll summarize them in my own words as:
               | 
               | 1) a CA can issue an illegitimate certificate (gives four
               | links where that's happened), and "cross your fingers and
               | hope transparency and oversight works" for CAA records
               | 
               | 2) difficulties of determining a competent certificate
               | authority.
               | 
               | 3) size still gives clues about content (see also
               | https://news.ycombinator.com/item?id=14070130 ), so you
               | still have some information leakage, which means you have
               | to worry about your threat model to figure out if
               | something like padding frames is worthwhile
               | 
               | 4) speaking of threat model, do you really think your
               | phone, or the phones of your users, don't include certs
               | that lets the telco/government/etc. do #1?
               | 
               | FWIW, found that link from comments after jwz's recent
               | posting about problems updating from letsencrypt using
               | certbot on CentOS. - https://web.archive.org/web/20210118
               | 183806/https://www.jwz.o... .
               | 
               | FWIW, my web site has been around for 20 years, serving
               | static files mostly containing a blurb about my services,
               | my blog, and various writings and source code I've
               | developed and released.
               | 
               | I still can't figure out why I should care to switch to
               | https. I can't figure out any relevant threat model to
               | justify the work or worry about possible failure cases.
               | 
               | Eg, "Let's Encrypt warns about a third of Android devices
               | will from next year stumble over sites that use its
               | certs" - https://www.theregister.com/2020/11/06/android_e
               | ncryption_ce... . (Updated earlier this month: Let's
               | Encrypt "developed a new certificate chain that will
               | prevent incompatibility with these devices to allow more
               | time for them to age out of the market.")
               | 
               | FWIW, my phone is 10 years old.
        
               | MrRadar wrote:
               | The reason to do it is because while HTTPS is not perfect
               | (especially when it comes to certificates), the attacks
               | against unencrypted and unauthenticated plaintext HTTP
               | (as I outlined in my other post) are incredibly trivial
               | in comparison. The main point of HTTPS-only is to make
               | the attacks significantly harder and more costly to
               | execute and easier to detect when they do happen. We
               | cannot let the perfect be the enemy of the good. Are
               | _you_ comfortable with ISPs injecting ads into your blog?
               | [1][2]
               | 
               | > FWIW, my phone is 10 years old.
               | 
               | I'm curious, which phone is this and what do you use it
               | for?
               | 
               | The oldest phones I keep in somewhat regular use are a
               | Moto X (8 years old) and a Moto E (6 years old) which I
               | maintain service on using free service providers (which
               | require I use their service at least once each month or
               | my service will be discontinued). When I turn those
               | phones on each month to place a call with them, they take
               | at least an hour to download and install app updates
               | before I can even start using them. On the Moto E I've
               | had to uninstall most apps because the internal storage
               | has been nearly exhausted just by installing the latest
               | updates for the bundled apps. On both phones even just
               | bringing up the keyboard after I select a text field
               | takes multiple seconds and any kind of multitasking is
               | out of the question. I could not imagine trying to use
               | either of those phones on a daily basis.
               | 
               | [1] https://arstechnica.com/tech-policy/2013/04/how-a-
               | banner-ad-...
               | 
               | [2] https://www.reddit.com/r/india/comments/8ry1k4/does_y
               | our_isp...
        
               | naf77 wrote:
               | The threat model is malicious injection, not
               | (some)information leakage.
               | 
               | > my web site has been around for 20 years, serving
               | static files mostly containing a blurb about my service,
               | my blog,
               | 
               | Your http website will be used for malicious injection,
               | it doesn't matter how deep it is in the long tail. Are
               | you ok with that? Can you take minimal measures to
               | protect me, the user, from getting a malicious injection?
               | 
               | Regarding rogue CAs, most modern OS (Android, Windows)
               | report back malicious chains to their mothership, quickly
               | detecting and eliminating rogue CAs. It's not the wild
               | west anymore.
        
               | apple_innocent wrote:
               | Why 1.3? Most sites today are using TLSv1.2 at best, not
               | 1.3.
               | 
               | One argument it is/was "security theater"[1] is that
               | there were/are numerous programs that "added support for
               | SSL/TLS" under pressure to conform but did not bother to
               | add authenticaton measures such as hostname checking and
               | validation, which was not even a function of the OpenSSL
               | library until 2015.
               | 
               | 1. Adopting SSL/TLS for accessibility reasons instead of
               | security reasons.
        
             | naf77 wrote:
             | HTTPS-everywhere, along with constant monitoring and
             | reporting of certificate chains by the browser, are
             | designed to protect against QUANTUM attacks [1], which, ~10
             | years ago, was being scaled to support million of
             | simultaneous attacked devices.
             | 
             | It is not cargo-cult security.
             | 
             | [1] https://en.wikipedia.org/wiki/Tailored_Access_Operation
             | s#QUA...
        
               | superkuh wrote:
               | HTTPS Everywhere (client side option) is great. HTTPS
               | only (server side option) is not.
        
               | naf77 wrote:
               | HTTPS only is a "Fail Closed" system, ie it blocks access
               | in case of failure. This is safe for the general
               | population.
               | 
               | HTTPS/HTTP mixed support is a "Fail Open" system, ie it
               | allows (unencrypted) access in case of failure. This is
               | unsafe for the general population, see QUANTUM (above).
        
               | superkuh wrote:
               | You can argue for wearing a bulletproof vest at home if
               | you're an iraqi nuclear scientist. But for most people it
               | doesn't make sense and does more harm than good.
               | 
               | In the same way, HTTPs _only_ , *requiring* a system that
               | "fails open", is bad for the general population.
               | HTTP+HTTPS, yes, definitely. HTTPS only, no, only for
               | sites and contexts where the rigid security is justified.
        
       | [deleted]
        
       | 1024core wrote:
       | I have a general question about these SDRs: what is the latency
       | between when the radio wave "hits" the dongle, and when it is
       | detected by the software framework?
        
         | naf77 wrote:
         | Buffers, buffers everywhere... It depends on the sampling rate
         | and technology (USB, ethernet, direct PCI), but in general
         | 1msec is achievable, 10microsec is not achievable.
         | 
         | That's why BladeRF-wiphy (
         | https://news.ycombinator.com/item?id=25814237 ) implements the
         | lower level phy on FPGA - there's no way to reply an IEEE
         | 802.11 ACK frame within 10 microseconds of the end of the
         | received frame, as required by the standard.
        
         | dlkinney wrote:
         | Depends on your buffer size, bandwidth, and what you're
         | demodulating/decoding, but it's pretty fast. With a narrow
         | bandwidth on a fast port and simple modulation/encoding, maybe
         | a few milliseconds?
        
           | naf77 wrote:
           | Counter-intuitively, it is often difficult to reach low
           | latency with "narrow bandwidth" (you mean low sampling rate),
           | because many SDR interfaces are designed to fill full packets
           | with data, not send tiny packets (ex: Ethernet packets). This
           | problem goes away above 1-10Msps.
        
         | Evidlo wrote:
         | A few ms as others have said, but it's also a non-deterministic
         | delay.
         | 
         | This is a problem for applications like time-of-flight
         | measurement, so one way to account for this is to send a known
         | signal on TX and look for it on RX
        
       | the_only_law wrote:
       | Somewhat unrelated but does anyone have any good resources for
       | learning GNU radio and SDR for someone who's mostly and idiot. I
       | took a single calc course in HS (which I hardly remember) and
       | have some very limited digital communications knowledge from
       | watching a few videos. I know what I want to eventually build and
       | have a nice SDR, but I don't know how to use GNU radio. Most of
       | the blocks I see outside some rather specific modulation ones
       | seem to be primitive operations.
        
         | she11c0de wrote:
         | You may find Michael Ossmann's SDR course [1] helpful - it
         | builds the knowledge from the groud up and uses GRC for
         | implementation.
         | 
         | [1] https://greatscottgadgets.com/sdr/
        
       | cogman10 wrote:
       | OK, so anyone more familiar with this project, how possible would
       | it be to make my own home network streaming service for OTA
       | radio?
       | 
       | Like, I think it'd be fun to have something like an http server
       | or whatever in my home that I could hit something like
       | "streamer/99.9fm" and get an opus audio stream for that station.
        
         | jimktrains2 wrote:
         | You don't strictly need GNU Radio for something like that. A
         | cheap RTL-SDR dongle and the `rtl_fm` command could work.
        
         | na85 wrote:
         | I played around with this a bit last year when I first got my
         | HackRF. It's got quite the learning curve if you, like me, are
         | not already knowledgeable about RF and SDR.
         | 
         | First step for your desired use case would be, I think, to
         | acquire an SDR module that can receive broadcast FM and then it
         | would simply be a matter of having your server command the SDR
         | to tune to 99.9 MHz and then stream the result to the network.
        
         | [deleted]
        
       | iracigt wrote:
       | They moved away from SWIG and to PyBind11. As they mention, this
       | is going to be an annoying transition for my custom out-of-tree
       | modules. Overall though, I'm excited for the changes.
       | 
       | Lots of new GUI blocks in this release. I'm especially glad to
       | see the new eye diagram.
       | 
       | Also the ability to load non-WAV audio files will be nice.
       | OGG/Vorbis and FLAC are now supported. Plus a slew of minor
       | conveniences such as a freq shift block and scaling options in
       | the IShort to Complex block (useful for loading recorded samples
       | from hardware).
       | 
       | If only it would compile easily on my Mac.
       | (https://github.com/ktemkin/gnuradio-for-mac-without-macports has
       | a prebuilt 3.8 version)
        
       | MaxBarraclough wrote:
       | I have nothing substantive to contribute here but it's always
       | nice to see a GNU project with a decent website. Presentable,
       | clean, modern. Good stuff. My only quibble is that it's very
       | slightly low on contrast.
        
         | jackspratt33 wrote:
         | Make a bookmarklet with this:
         | 
         | javascript:var%20x%20=%20document.querySelectorAll("div,p,li,a,
         | hr,em,font,strong,h1,h2,h3,td");var%20i;for%20(i%20=%200;%20i%2
         | 0<%20x.length;%20i++)%20{%20%20%20%20x[i].style.backgroundColor
         | %20=%20"white";x[i].style.color%20=%20"black";}undefined;//aler
         | t("Done");;
         | 
         | It changes the background to white and the text color to black.
         | I use that on worse websites than the GNU Radio one.
        
           | MaxBarraclough wrote:
           | Interesting trick. When I find that a website's design would
           | be improved by removing it, I tend to go with Reader Mode.
        
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