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Post Mortem: A single whitespace character

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Re: Post Mortem: A single whitespace character

#141

Post by asveikau »

linuxlizard wrote: post #140
asveikau wrote: post #97

strcpy( ( char * ) commsOrderBuffer, "GET /v1/printer/"); strcat( ( char * ) commsOrderBuffer, ( char * ) settings.getIMEI()); strcat( ( char * ) commsOrderBuffer, "/orders.txt HTTP/1.1\r\n"); strcat( ( char * ) commsOrderBuffer, "HOST: "); strcat( ( char * ) commsOrderBuffer, SERVER_NAME); strcat( ( char * ) commsOrderBuffer, "\r\n"); strcat( ( char * ) commsOrderBuffer, "Authorization: Basic "); What the.... O(n) s…

The Arduino embedded C library (which I'm assuming they're using) isn't as rich as a Glibc or uclibc. Sometimes I have to fall back on very old school methods to build complex strings.

This is a very weak excuse to use strcat(). Writing something that actually tracks the length instead of recomputing it every time takes 5 minutes.

Re: Post Mortem: A single whitespace character

#142

Post by linuxlizard »

goleksiak wrote: post #69
pilif wrote: post #50

Likely "Cowboy" is a transparent proxy added by your mobile service provider. I had a similar thing happening a year ago when the mobile provider used by most of our barcode scanners decided to add a transparent proxy into the loop (without telling anybody). The solution for this problem: Use SSL. I mean: There are already many good reasons to use SSL, but whenever you need to send any kind of mission critical data o…

We would really like to use HTTPS but it's not supported by the Arduino chipset as I understand it. Though I'm not the hardware guy here at eatabit...

Why not ROT13? Or a simple substitution cypher?

Not trying to be silly. But if the only goal is to prevent man-in-the-middle attacks such as someone mangling the data, why not "corrupt" the data such that the phone company in the middle can't read it?

You control both ends. You can make your own "security".

You're not explicitly worried about security. You're not worried about Evil Person reading your messages. You just want your carrier to stop f'ing with your data.

If the data is slightly corrupted so the carrier's crappy software can't recognize it as http headers then the carrier's software (hopefully) won't fck with it.

Re: Post Mortem: A single whitespace character

#143

Post by SamReidHughes »

robomartin wrote: post #126
DanBC wrote: post #124

Earlier quoted context omitted.

I didn't downvote. People downvote corrections because they're usually noise. When someone makes a typo - and homophones are usually slips equivalent to typos - it's noise to point it out.

It's only noise if it has no value. A post such as mine would not have to appear too frequently for HN readers who might be having difficulties with such words to understand the problem and correct their writing. Not going after perfect English, few of us could approach that. But I see a few common patterns on HN all the time and nobody takes a second to say "hey buddy, just in case this wasn't clear to you, here's a…

> and nobody takes a second to say "hey buddy, just in case this wasn't clear to you, here's a helpful tip".

"hey" should be capitalized, it's at the beginning of a complete sentence. Also, a comma should be before the quotation.

> No down vote, perhaps an up-vote

down-vote and up-vote should at least be hyphenated consistently.

> One of the things that continues to disturb me the most about HN is how thin skinned the community seems to be. It is impossible to consistently offer a contrasting point of view here without down-vote attacks that make your point of view virtually disappear. Mind you, this particular post isn't that. It just reminds me that HN is really weird.

Likewise, down-vote should be hyphenated consistently with the previous use.

> I get down voted a lot despite the fact that I am a successful entrepreneur since age 15 who has built several companies and continues to do so. My perspective, however, seems seldom welcome here (based on how often I am down-voted) because I don't tow the line of the 20-somethings that are the bulk of this audience. Instead of learning they choose to pound what they don't like out of existence. Weird.

I don't get what kind of prank you're trying to pull here. Is it "down voted" or "down-voted"???

Just being helpful!!

Re: Post Mortem: A single whitespace character

#144

Post by monokrome »

pilif wrote: post #85
rubiquity wrote: post #73

Earlier quoted context omitted.

Cowboy is the name of an Erlang web server and Heroku uses Erlang for their routing. I imagine the reason Cowboy is showing up is due to Heroku's routing layer.

I would agree, but the fact that it suddenly stopped working points to carrier interference rather than Heroku (because as a developer focussed company, they would have informed OPs company of the change)

Heroku isn't in a frozen state. I'm sure that they change the code daily. The fact that it suddently stopped working doesn't really point to any specific endpoint unless you know which ones have changed. Then it might mean something.

Re: Post Mortem: A single whitespace character

#145

Post by jimrhoskins »

spydum wrote: post #6

The Server: cowboy tag is from an Erlang web server: https://github.com/ninenines/cowboy/blob/master/src/cowboy_p... I'm guessing around here would be interesting to add a test case to handle. As far as whose server this is? I'd guess Heroku or AWS, though it's plenty possible T-Mobile could have devised some proxy to inspect traffic, but seems unlikely they would do so with Cowboy?

Didn't heroku turn off legacy routing last week? I was getting emails warning me to update to their new routing rules by Monday. Seems like it could be related.

Re: Post Mortem: A single whitespace character

#146

Post by Animats »

Another broken network device which takes it upon itself to mess with TCP connections passing through.

I ran into this a few years ago with Coyote Point load balancers. It turns out that if you send HTTP headers to a Coyote Point load balancer, and the last header field is "User-agent", and that field ends with "m" but does not otherwise contain "m", the connection does not go through the load balancer.

Complaining to Coyote Point produced typical clueless responses such as "Upgrade your software". (The problem wasn't at my end, but at sites with Coyote Point devices. Fortunately, I knew someone who had a Coyote Point unit, and we were able to force the situation there.) I had our system ("Sitetruth.com site rating system", note the "m") put an unnecessary "Accept" header field at the end of the header to work around the problem.

Coyote Point's filtering software is regular-expression based, and I suspect that somewhere, there is a rule with a "\m" instead of "\n".

A current issue: there are some sites where, if you make three HTTP requests for the same URL from the same IP address in a short period, further requests are ignored for about 15 seconds. You can make this happen with three "wget" requests. Try "wget http://bitcointalk.org" three times in quick succession. Amusingly, this limiter only applies for HTTP sessions, not HTTPS.

Re: Post Mortem: A single whitespace character

#147

Post by swordswinger12 »

goleksiak wrote: post #69
pilif wrote: post #50

Likely "Cowboy" is a transparent proxy added by your mobile service provider. I had a similar thing happening a year ago when the mobile provider used by most of our barcode scanners decided to add a transparent proxy into the loop (without telling anybody). The solution for this problem: Use SSL. I mean: There are already many good reasons to use SSL, but whenever you need to send any kind of mission critical data o…

We would really like to use HTTPS but it's not supported by the Arduino chipset as I understand it. Though I'm not the hardware guy here at eatabit...

You guys build all the hardware - why not just use one of the pre-shared key TLS ciphersuites? No expensive public-key crypto required, just AES and SHA.

Re: Post Mortem: A single whitespace character

#148

Post by imanaccount247 »

kstrauser wrote: post #79

If this were my team, I would be unsettled by the fact that we never caught it in testing. Did no one write tests to exercise this part of the app - the one where we're handcrafting HTTP requests? Objectively, you need to write more tests. At the minimum, this bug should have a regression test so that it can never accidentally happen again (say when a dev merges an old branch in for whatever reason).

>Objectively, you need to write more tests

That is precisely the opposite of objective. Personal thoughts, feelings and opinions are subjective by definition. 2+2=4 is objective. "You need to put more cheese on that pizza" is subjective.

Re: Post Mortem: A single whitespace character

#149

Post by ajanuary »

gpvos wrote: post #64
ajanuary wrote: post #55

Earlier quoted context omitted.

I think you're reading it incorrectly. You can have an empty segment in the path. The BNF for a segment is: segment = *pchar Which according to RFC2234 section 3.6 means zero or more repetitions.

But then the server may still decide that an empty segment is so meaningless that it will refuse it. In fact, it would not be a smart move to just treat double slashes the same as single ones, because of relative URLs: a ".." segment only removes one slash, so the hierarchy levels would get messed up. thttpd is doing the smart thing here. As one of my teachers at university would say: the empty segment is also a segm…

Yes, it's a valid URI but //robots.txt is different resource to /robots.txt. It seems thttpd is probay doing the right thing.

Re: Post Mortem: A single whitespace character

#150

Post by robomartin »

SamReidHughes wrote: post #143
robomartin wrote: post #126

Earlier quoted context omitted.

It's only noise if it has no value. A post such as mine would not have to appear too frequently for HN readers who might be having difficulties with such words to understand the problem and correct their writing. Not going after perfect English, few of us could approach that. But I see a few common patterns on HN all the time and nobody takes a second to say "hey buddy, just in case this wasn't clear to you, here's a…

> and nobody takes a second to say "hey buddy, just in case this wasn't clear to you, here's a helpful tip". "hey" should be capitalized, it's at the beginning of a complete sentence. Also, a comma should be before the quotation. > No down vote, perhaps an up-vote down-vote and up-vote should at least be hyphenated consistently. > One of the things that continues to disturb me the most about HN is how thin skinned th…

Let me guess. You are 15 years old and just ditched school to screw around on HN. Right?

The difference, in case you did not understand that. Is that my earlier comment was purely constructive in nature.

Your comment was a juvenile "I'll show him. I'll rip his writing apart and put him to shame".

One is an adult constructive post. The other is what I would not allow from my eight year old kid.

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