Tag Archives: signal

Russian Censorship of Telegram

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/06/russian_censors.html

Internet censors have a new strategy in their bid to block applications and websites: pressuring the large cloud providers that host them. These providers have concerns that are much broader than the targets of censorship efforts, so they have the choice of either standing up to the censors or capitulating in order to maximize their business. Today’s Internet largely reflects the dominance of a handful of companies behind the cloud services, search engines and mobile platforms that underpin the technology landscape. This new centralization radically tips the balance between those who want to censor parts of the Internet and those trying to evade censorship. When the profitable answer is for a software giant to acquiesce to censors’ demands, how long can Internet freedom last?

The recent battle between the Russian government and the Telegram messaging app illustrates one way this might play out. Russia has been trying to block Telegram since April, when a Moscow court banned it after the company refused to give Russian authorities access to user messages. Telegram, which is widely used in Russia, works on both iPhone and Android, and there are Windows and Mac desktop versions available. The app offers optional end-to-end encryption, meaning that all messages are encrypted on the sender’s phone and decrypted on the receiver’s phone; no part of the network can eavesdrop on the messages.

Since then, Telegram has been playing cat-and-mouse with the Russian telecom regulator Roskomnadzor by varying the IP address the app uses to communicate. Because Telegram isn’t a fixed website, it doesn’t need a fixed IP address. Telegram bought tens of thousands of IP addresses and has been quickly rotating through them, staying a step ahead of censors. Cleverly, this tactic is invisible to users. The app never sees the change, or the entire list of IP addresses, and the censor has no clear way to block them all.

A week after the court ban, Roskomnadzor countered with an unprecedented move of its own: blocking 19 million IP addresses, many on Amazon Web Services and Google Cloud. The collateral damage was widespread: The action inadvertently broke many other web services that use those platforms, and Roskomnadzor scaled back after it became clear that its action had affected services critical for Russian business. Even so, the censor is still blocking millions of IP addresses.

More recently, Russia has been pressuring Apple not to offer the Telegram app in its iPhone App Store. As of this writing, Apple has not complied, and the company has allowed Telegram to download a critical software update to iPhone users (after what the app’s founder called a delay last month). Roskomnadzor could further pressure Apple, though, including by threatening to turn off its entire iPhone app business in Russia.

Telegram might seem a weird app for Russia to focus on. Those of us who work in security don’t recommend the program, primarily because of the nature of its cryptographic protocols. In general, proprietary cryptography has numerous fatal security flaws. We generally recommend Signal for secure SMS messaging, or, if having that program on your computer is somehow incriminating, WhatsApp. (More than 1.5 billion people worldwide use WhatsApp.) What Telegram has going for it is that it works really well on lousy networks. That’s why it is so popular in places like Iran and Afghanistan. (Iran is also trying to ban the app.)

What the Russian government doesn’t like about Telegram is its anonymous broadcast feature­ — channel capability and chats — ­which makes it an effective platform for political debate and citizen journalism. The Russians might not like that Telegram is encrypted, but odds are good that they can simply break the encryption. Telegram’s role in facilitating uncontrolled journalism is the real issue.

Iran attempts to block Telegram have been more successful than Russia’s, less because Iran’s censorship technology is more sophisticated but because Telegram is not willing to go as far to defend Iranian users. The reasons are not rooted in business decisions. Simply put, Telegram is a Russian product and the designers are more motivated to poke Russia in the eye. Pavel Durov, Telegram’s founder, has pledged millions of dollars to help fight Russian censorship.

For the moment, Russia has lost. But this battle is far from over. Russia could easily come back with more targeted pressure on Google, Amazon and Apple. A year earlier, Zello used the same trick Telegram is using to evade Russian censors. Then, Roskomnadzor threatened to block all of Amazon Web Services and Google Cloud; and in that instance, both companies forced Zello to stop its IP-hopping censorship-evasion tactic.

Russia could also further develop its censorship infrastructure. If its capabilities were as finely honed as China’s, it would be able to more effectively block Telegram from operating. Right now, Russia can block only specific IP addresses, which is too coarse a tool for this issue. Telegram’s voice capabilities in Russia are significantly degraded, however, probably because high-capacity IP addresses are easier to block.

Whatever its current frustrations, Russia might well win in the long term. By demonstrating its willingness to suffer the temporary collateral damage of blocking major cloud providers, it prompted cloud providers to block another and more effective anti-censorship tactic, or at least accelerated the process. In April, Google and Amazon banned­ — and technically blocked­ — the practice of “domain fronting,” a trick anti-censorship tools use to get around Internet censors by pretending to be other kinds of traffic. Developers would use popular websites as a proxy, routing traffic to their own servers through another website­ — in this case Google.com­ — to fool censors into believing the traffic was intended for Google.com. The anonymous web-browsing tool Tor has used domain fronting since 2014. Signal, since 2016. Eliminating the capability is a boon to censors worldwide.

Tech giants have gotten embroiled in censorship battles for years. Sometimes they fight and sometimes they fold, but until now there have always been options. What this particular fight highlights is that Internet freedom is increasingly in the hands of the world’s largest Internet companies. And while freedom may have its advocates — ­the American Civil Liberties Union has tweeted its support for those companies, and some 12,000 people in Moscow protested against the Telegram ban­ — actions such as disallowing domain fronting illustrate that getting the big tech companies to sacrifice their near-term commercial interests will be an uphill battle. Apple has already removed anti-censorship apps from its Chinese app store.

In 1993, John Gilmore famously said that “The Internet interprets censorship as damage and routes around it.” That was technically true when he said it but only because the routing structure of the Internet was so distributed. As centralization increases, the Internet loses that robustness, and censorship by governments and companies becomes easier.

This essay previously appeared on Lawfare.com.

FCC Asks Amazon & eBay to Help Eliminate Pirate Media Box Sales

Post Syndicated from Andy original https://torrentfreak.com/fcc-asks-amazon-ebay-to-help-eliminate-pirate-media-box-sales-180530/

Over the past several years, anyone looking for a piracy-configured set-top box could do worse than search for one on Amazon or eBay.

Historically, people deploying search terms including “Kodi” or “fully-loaded” were greeted by page after page of Android-type boxes, each ready for illicit plug-and-play entertainment consumption following delivery.

Although the problem persists on both platforms, people are now much less likely to find infringing devices than they were 12 to 24 months ago. Under pressure from entertainment industry groups, both Amazon and eBay have tightened the screws on sellers of such devices. Now, however, both companies have received requests to stem sales from a completetey different direction.

In a letter to eBay CEO Devin Wenig and Amazon CEO Jeff Bezos first spotted by Ars, FCC Commissioner Michael O’Rielly calls on the platforms to take action against piracy-configured boxes that fail to comply with FCC equipment authorization requirements or falsely display FCC logos, contrary to United States law.

“Disturbingly, some rogue set-top box manufacturers and distributors are exploiting the FCC’s trusted logo by fraudulently placing it on devices that have not been approved via the Commission’s equipment authorization process,” O’Rielly’s letter reads.

“Specifically, nine set-top box distributors were referred to the FCC in October for enabling the unlawful streaming of copyrighted material, seven of which displayed the FCC logo, although there was no record of such compliance.”

While O’Rielly admits that the copyright infringement aspects fall outside the jurisdiction of the FCC, he says it’s troubling that many of these devices are used to stream infringing content, “exacerbating the theft of billions of dollars in American innovation and creativity.”

As noted above, both Amazon and eBay have taken steps to reduce sales of pirate boxes on their respective platforms on copyright infringement grounds, something which is duly noted by O’Rielly. However, he points out that devices continue to be sold to members of the public who may believe that the devices are legal since they’re available for sale from legitimate companies.

“For these reasons, I am seeking your further cooperation in assisting the FCC in taking steps to eliminate the non-FCC compliant devices or devices that fraudulently bear the FCC logo,” the Commissioner writes (pdf).

“Moreover, if your company is made aware by the Commission, with supporting evidence, that a particular device is using a fraudulent FCC label or has not been appropriately certified and labeled with a valid FCC logo, I respectfully request that you commit to swiftly removing these products from your sites.”

In the event that Amazon and eBay take action under this request, O’Rielly asks both platforms to hand over information they hold on offending manufacturers, distributors, and suppliers.

Amazon was quick to respond to the FCC. In a letter published by Ars, Amazon’s Public Policy Vice President Brian Huseman assured O’Rielly that the company is not only dedicated to tackling rogue devices on copyright-infringement grounds but also when there is fraudulent use of the FCC’s logos.

Noting that Amazon is a key member of the Alliance for Creativity and Entertainment (ACE) – a group that has been taking legal action against sellers of infringing streaming devices (ISDs) and those who make infringing addons for Kodi-type systems – Huseman says that dealing with the problem is a top priority.

“Our goal is to prevent the sale of ISDs anywhere, as we seek to protect our customers from the risks posed by these devices, in addition to our interest in protecting Amazon Studios content,” Huseman writes.

“In 2017, Amazon became the first online marketplace to prohibit the sale of streaming media players that promote or facilitate piracy. To prevent the sale of these devices, we proactively scan product listings for signs of potentially infringing products, and we also invest heavily in sophisticated, automated real-time tools to review a variety of data sources and signals to identify inauthentic goods.

“These automated tools are supplemented by human reviewers that conduct manual investigations. When we suspect infringement, we take immediate action to remove suspected listings, and we also take enforcement action against sellers’ entire accounts when appropriate.”

Huseman also reveals that since implementing a proactive policy against such devices, “tens of thousands” of listings have been blocked from Amazon. In addition, the platform has been making criminal referrals to law enforcement as well as taking civil action (1,2,3) as part of ACE.

“As noted in your letter, we would also appreciate the opportunity to collaborate further with the FCC to remove non-compliant devices that improperly use the FCC logo or falsely claim FCC certification. If any FCC non-compliant devices are identified, we seek to work with you to ensure they are not offered for sale,” Huseman concludes.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and more. We also have VPN reviews, discounts, offers and coupons.

Enchanting images with Inky Lines, a Pi‑powered polargraph

Post Syndicated from Helen Lynn original https://www.raspberrypi.org/blog/enchanting-images-inky-lines-pi-powered-polargraph/

A hanging plotter, also known as a polar plotter or polargraph, is a machine for drawing images on a vertical surface. It does so by using motors to control the length of two cords that form a V shape, supporting a pen where they meet. We’ve featured one on this blog before: Norbert “HomoFaciens” Heinz’s video is a wonderfully clear introduction to how a polargraph works and what you have to consider when you’re putting one together.

Today, we look at Inky Lines, by John Proudlock. With it, John is creating a series of captivating and beautiful pieces, and with his most recent work, each rendering of an image is unique.

The Inky Lines plotter draws a flock of seagulls in blue ink on white paper. The print head is suspended near the bottom left corner of the image, as the pen inks the wing of a gull

An evolving project

The project isn’t new – John has been working on it for at least a couple of years – but it is constantly evolving. When we first spotted it, John had just implemented code to allow the plotter to produce mesmeric, spiralling patterns.

A blue spiral pattern featuring overlapping "bubbles"
A dense pink spiral pattern, featuring concentric circles and reminiscent of a mandala
A blue spirograph-type pattern formed of large overlapping squares, each offset from its neighbour by a few degrees, producing a four-spiral-armed "galaxy" shape where lines overlap. The plotter's print head is visible in a corner of the image

But we’re skipping ahead. Let’s go back to the beginning.

From pixels to motor movements

John starts by providing an image, usually no more than 100 pixels wide, to a Raspberry Pi. Custom software that he wrote evaluates the darkness of each pixel and selects a pattern of a suitable density to represent it.

The two cords supporting the plotter’s pen are wound around the shafts of two stepper motors, such that the movement of the motors controls the length of the cords: the program next calculates how much each motor must move in order to produce the pattern. The Raspberry Pi passes corresponding instructions to two motor circuits, which transform the signals to a higher voltage and pass them to the stepper motors. These turn by very precise amounts, winding or unwinding the cords and, very slowly, dragging the pen across the paper.

A Raspberry Pi in a case, with a wide flex connected to a GPIO header
The Inky Lines plotter's print head, featuring cardboard and tape, draws an apparently random squiggle
A large area of apparently random pattern drawn by the plotter

John explains,

Suspended in-between the two motors is a print head, made out of a new 3-d modelling material I’ve been prototyping called cardboard. An old coat hanger and some velcro were also used.

(He’s our kind of maker.)

Unique images

The earlier drawings that John made used a repeatable method to render image files as lines on paper. That is, if the machine drew the same image a number of times, each copy would be identical. More recently, though, he has been using a method that yields random movements of the pen:

The pen point is guided around the image, but moves to each new point entirely at random. Up close this looks like a chaotic squiggle, but from a distance of a couple of meters, the human eye (and brain) make order from the chaos and view an infinite number of shades and a smoother, less mechanical image.

An apparently chaotic squiggle

This method means that no matter how many times the polargraph repeats the same image, each copy will be unique.

A gallery of work

Inky Lines’ website and its Instagram feed offer a collection of wonderful pieces John has drawn with his polargraph, and he discusses the different techniques and types of image that he is exploring.

A 3 x 3 grid of varied and colourful images from inkylinespolargraph's Instagram feed

They range from holiday photographs, processed to extract particular features and rendered in silhouette, to portraits, made with a single continuous line that can be several hundred metres long, to generative images spirograph images like those pictured above, created by an algorithm rather than rendered from a source image.

The post Enchanting images with Inky Lines, a Pi‑powered polargraph appeared first on Raspberry Pi.

Japan’s Directorate for Signals Intelligence

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/05/japans_director.html

The Intercept has a long article on Japan’s equivalent of the NSA: the Directorate for Signals Intelligence. Interesting, but nothing really surprising.

The directorate has a history that dates back to the 1950s; its role is to eavesdrop on communications. But its operations remain so highly classified that the Japanese government has disclosed little about its work ­ even the location of its headquarters. Most Japanese officials, except for a select few of the prime minister’s inner circle, are kept in the dark about the directorate’s activities, which are regulated by a limited legal framework and not subject to any independent oversight.

Now, a new investigation by the Japanese broadcaster NHK — produced in collaboration with The Intercept — reveals for the first time details about the inner workings of Japan’s opaque spy community. Based on classified documents and interviews with current and former officials familiar with the agency’s intelligence work, the investigation shines light on a previously undisclosed internet surveillance program and a spy hub in the south of Japan that is used to monitor phone calls and emails passing across communications satellites.

The article includes some new documents from the Snowden archive.

Police Forces Around Europe Hit Pirate IPTV Operation

Post Syndicated from Andy original https://torrentfreak.com/police-forces-around-europe-hit-pirate-iptv-operation-180519/

Once upon a time, torrent and web streaming sites were regularly in the headlines while being targeted by the authorities. With the rise of set-top box streaming, actions against pirate IPTV operations are more regularly making the news.

In an operation coordinated by the public prosecutor’s office in Rome, 150 officers of the Provincial Command of the Guardia di Finanza (GdF) this week targeted what appears to be a fairly large unauthorized IPTV provider.

Under the banner Operation Spinoff, in Italy, more than 50 searches were carried out in 20 provinces of 11 regions. Five people were arrested. Elsewhere in Europe – in Switzerland, Germany and Spain – the Polizei Basel-Landschaft, the Kriminal Polizei and the Policia Nacional coordinated to execute warrants.

A small selection of the service on offer

“Through technical and ‘in-the-field’ investigations and the meticulous reconstruction of financial flows, carried out mainly through prepaid credit cards or payment web platforms, investigators have reconstructed the activity of a pyramid-like criminal structure dedicated to the illegal decryption and diffusion of pay-per-view television content through the Internet,” the GdF said in a statement.

Italian authorities report that the core of the IPTV operation were its sources of original content and channels. These were located in a range of diverse locations such as companies, commercial premises, garages and even private homes. Inside each location was equipment to receive, decrypt and capture signals from broadcasters including Sky TV.

Italian police examine hardware

These signals were collected together to form a package of channels which were then transmitted via the Internet and sold to the public in the form of an IPTV subscription. Packages were reportedly priced between 15 and 20 euros per month.

It’s estimated that between the 49 individuals said to be involved in the operation, around one million euros was generated. All are suspected of copyright infringement and money laundering offenses. Of the five Italian citizens reported to be at the core of the operations, four were taken into custody and one placed under house arrest.

Reports identify the suspects as: ‘AS’, born 1979 and residing in Lorrach, Germany. ‘RM’, born 1987 and living in Sarno, Italy. ‘LD’, born 1996 and also living in Sarno, Italy. ‘GP’, born 1990, living in Pordenone, Italy. And ‘SM’, born 1981 and living in Zagarolo, Italy.

More hardware

Players at all levels of the business are under investigation, from the sources who decrypted the signals to the sellers and re-sellers of the content to end users. Also under the microscope are people said to have laundered the operation’s money through credit cards and payment platforms.

The GdF describes the pirate IPTV operation in serious terms, noting that it aimed to set up a “parallel distribution company able to provide services that are entirely analogous to lawful companies, from checks on the feasibility of installing the service to maintaining adequate standards and technical assistance to customers.”

Source: TF, for the latest info on copyright, file-sharing, torrent sites and more. We also have VPN reviews, discounts, offers and coupons.

UK soldiers design Raspberry Pi bomb disposal robot

Post Syndicated from Helen Lynn original https://www.raspberrypi.org/blog/uk-soldiers-design-raspberry-pi-bomb-disposal-robot/

Three soldiers in the British Army have used a Raspberry Pi to build an autonomous robot, as part of their Foreman of Signals course.

Meet The Soldiers Revolutionising Bomb Disposal

Three soldiers from Blandford Camp have successfully designed and built an autonomous robot as part of their Foreman of Signals Course at the Dorset Garrison.

Autonomous robots

Forces Radio BFBS carried a story last week about Staff Sergeant Jolley, Sergeant Rana, and Sergeant Paddon, also known as the “Project ROVER” team. As part of their Foreman of Signals training, their task was to design an autonomous robot that can move between two specified points, take a temperature reading, and transmit the information to a remote computer. The team comments that, while semi-autonomous robots have been used as far back as 9/11 for tasks like finding people trapped under rubble, nothing like their robot and on a similar scale currently exists within the British Army.

The ROVER buggy

Their build is named ROVER, which stands for Remote Obstacle aVoiding Environment Robot. It’s a buggy that moves on caterpillar tracks, and it’s tethered; we wonder whether that might be because it doesn’t currently have an on-board power supply. A demo shows the robot moving forward, then changing its path when it encounters an obstacle. The team is using RealVNC‘s remote access software to allow ROVER to send data back to another computer.

Applications for ROVER

Dave Ball, Senior Lecturer in charge of the Foreman of Signals course, comments that the project is “a fantastic opportunity for [the team] to, even only halfway through the course, showcase some of the stuff they’ve learnt and produce something that’s really quite exciting.” The Project ROVER team explains that the possibilities for autonomous robots like this one are extensive: they include mine clearance, bomb disposal, and search-and-rescue campaigns. They point out that existing semi-autonomous hardware is not as easy to program as their build. In contrast, they say, “with the invention of the Raspberry Pi, this has allowed three very inexperienced individuals to program a robot very capable of doing these things.”

We make Raspberry Pi computers because we want building things with technology to be as accessible as possible. So it’s great to see a project like this, made by people who aren’t techy and don’t have a lot of computing experience, but who want to solve a problem and see that the Pi is an affordable and powerful tool that can help.

The post UK soldiers design Raspberry Pi bomb disposal robot appeared first on Raspberry Pi.

Details on a New PGP Vulnerability

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/05/details_on_a_ne.html

A new PGP vulnerability was announced today. Basically, the vulnerability makes use of the fact that modern e-mail programs allow for embedded HTML objects. Essentially, if an attacker can intercept and modify a message in transit, he can insert code that sends the plaintext in a URL to a remote website. Very clever.

The EFAIL attacks exploit vulnerabilities in the OpenPGP and S/MIME standards to reveal the plaintext of encrypted emails. In a nutshell, EFAIL abuses active content of HTML emails, for example externally loaded images or styles, to exfiltrate plaintext through requested URLs. To create these exfiltration channels, the attacker first needs access to the encrypted emails, for example, by eavesdropping on network traffic, compromising email accounts, email servers, backup systems or client computers. The emails could even have been collected years ago.

The attacker changes an encrypted email in a particular way and sends this changed encrypted email to the victim. The victim’s email client decrypts the email and loads any external content, thus exfiltrating the plaintext to the attacker.

A few initial comments:

1. Being able to intercept and modify e-mails in transit is the sort of thing the NSA can do, but is hard for the average hacker. That being said, there are circumstances where someone can modify e-mails. I don’t mean to minimize the seriousness of this attack, but that is a consideration.

2. The vulnerability isn’t with PGP or S/MIME itself, but in the way they interact with modern e-mail programs. You can see this in the two suggested short-term mitigations: “No decryption in the e-mail client,” and “disable HTML rendering.”

3. I’ve been getting some weird press calls from reporters wanting to know if this demonstrates that e-mail encryption is impossible. No, this just demonstrates that programmers are human and vulnerabilities are inevitable. PGP almost certainly has fewer bugs than your average piece of software, but it’s not bug free.

3. Why is anyone using encrypted e-mail anymore, anyway? Reliably and easily encrypting e-mail is an insurmountably hard problem for reasons having nothing to do with today’s announcement. If you need to communicate securely, use Signal. If having Signal on your phone will arouse suspicion, use WhatsApp.

I’ll post other commentaries and analyses as I find them.

EDITED TO ADD (5/14): News articles.

Slashdot thread.

Serious vulnerabilities with OpenPGP and S/MIME

Post Syndicated from corbet original https://lwn.net/Articles/754370/rss

The efail.de site describes a set of
vulnerabilities in the implementation of PGP and MIME that can cause the
disclosure of encrypted communications, including old messages. “In a
nutshell, EFAIL abuses active content of HTML emails, for example
externally loaded images or styles, to exfiltrate plaintext through
requested URLs.

The EFF recommends
uninstalling email-encryption tools that automatically
decrypt email entirely. “Until the flaws
described in the paper are more widely understood and fixed, users should
arrange for the use of alternative end-to-end secure channels, such as
Signal, and temporarily stop sending and especially reading PGP-encrypted

2018-05-03 python, multiprocessing, thread-ове и забивания

Post Syndicated from Vasil Kolev original https://vasil.ludost.net/blog/?p=3384

Всеки ден се убеждавам, че нищо не работи.

Открих забавен проблем с python и multiprocessing, който в момента още не мога да реша чий проблем е (в крайна сметка ще се окаже мой). Отне ми прилично количество време да го хвана и си струва да го разкажа.

Малко предистория: ползваме influxdb, в което тъпчем бая секундни данни, които после предъвкваме до минутни. InfluxDB има continuous queries, които вършат тази работа – на някакъв интервал от време хващат новите данни и ги сгъват. Тези заявки имаха няколко проблема:
– не се оправят с попълване на стари данни;
– изпълняват се рядко и минутните данни изостават;
– изпълняват се в общи линии в един thread, което кара минутните данни да изостават още повече (в нашия случай преди да ги сменим с около 12 часа).

Хванаха ме дяволите и си написах просто демонче на python, което да събира информация за различните бази какви данни могат да се сгънат, и паралелно да попълва данните. Работи в общи линии по следния начин:
– взима списък с базите данни
– пуска през multiprocessing-а да се събере за всяка база какви заявки трябва да се пуснат, на база на какви measurement-и има и докога са минутните и секундните данни в тях;
– пуска през multiprocessing-а събраните от предния pass заявки
– и така до края на света (или докато зависне).

След като навакса за няколко часа, успяваше да държи минутните данни в рамките на няколко минути от последните секундни данни, което си беше сериозно подобрение на ситуацията. Единственият проблем беше, че от време на време спираше да process-ва и увисваше.

Днес намерих време да го прегледам внимателно какво му се случва. Процесът изглежда като един parent и 5 fork()-нати child-а, като:
Parent-а спи във futex 0x22555a0;
Child 18455 във futex 0x7fdbfa366000;
Child 18546 read
Child 18457 във futex 0x7fdbfa366000
Child 18461 във futex 0x7fdbfa366000
Child 18462 във futex 0x7fdbfa366000
Child 18465 във futex 0x7fdbf908c2c0

Това не беше особено полезно, и се оказа, че стандартния python debugger (pdb) не може да се закача за съществуващи процеси, но за сметка на това gdb с подходящи debug символи може, и може да дава доста полезна информация. По този начин открих, че parent-а чака един child да приключи работата си:

#11 PyEval_EvalFrameEx (
[email protected]=Frame 0x235fb80, for file /usr/lib64/python2.7/multiprocessing/pool.py, line 543, in wait (self== 1525137960000000000 AND time < 1525138107000000000 GROUP BY time(1m), * fill(linear)\' in a read only context, please use a POST request instead', u'level': u'warning'}], u'statement_id': 0}]}, None], _callback=None, _chunksize=1, _number_left=1, _ready=False, _success=True, _cond=<_Condition(_Verbose__verbose=False, _Condition__lock=, acquire=, _Condition__waiters=[], release=) at remote 0x7fdbe0015310>, _job=45499, _cache={45499: < ...>}) a...(truncated), [email protected]=0) at /usr/src/debug/Python-2.7.5/Python/ceval.c:3040

Като в pool.py около ред 543 има следното:

class ApplyResult(object):


def wait(self, timeout=None):
if not self._ready:

Първоначално си мислех, че 18546 очаква да прочете нещо от грешното място, но излезе, че това е child-а, който е спечелил състезанието за изпълняване на следващата задача и чака да му я дадат (което изглежда се раздава през futex 0x7fdbfa366000). Един от child-овете обаче чака в друг lock:

(gdb) bt
#0 __lll_lock_wait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135
#1 0x00007fdbf9b68dcb in _L_lock_812 () from /lib64/libpthread.so.0
#2 0x00007fdbf9b68c98 in __GI___pthread_mutex_lock ([email protected]=0x7fdbf908c2c0 ) at ../nptl/pthread_mutex_lock.c:79
#3 0x00007fdbf8e846ea in _nss_files_gethostbyname4_r ([email protected]=0x233fa44 "localhost", [email protected]=0x7fdbecfcb8e0, [email protected]=0x7fdbecfcb340 "hZ \372\333\177",
[email protected]=1064, [email protected]=0x7fdbecfcb8b0, [email protected]=0x7fdbecfcb910, [email protected]=0x0) at nss_files/files-hosts.c:381
#4 0x00007fdbf9170ed8 in gaih_inet (name=, [email protected]=0x233fa44 "localhost", service=, [email protected]=0x7fdbecfcbb90, [email protected]=0x7fdbecfcb9f0,
[email protected]=0x7fdbecfcb9e0) at ../sysdeps/posix/getaddrinfo.c:877
#5 0x00007fdbf91745cd in __GI_getaddrinfo ([email protected]=0x233fa44 "localhost", [email protected]=0x7fdbecfcbbc0 "8086", [email protected]=0x7fdbecfcbb90, [email protected]=0x7fdbecfcbb78)
at ../sysdeps/posix/getaddrinfo.c:2431
#6 0x00007fdbeed8760d in socket_getaddrinfo (self=
, args=) at /usr/src/debug/Python-2.7.5/Modules/socketmodule.c:4193
#7 0x00007fdbf9e5fbb0 in call_function (oparg=
, pp_stack=0x7fdbecfcbd10) at /usr/src/debug/Python-2.7.5/Python/ceval.c:4408
#8 PyEval_EvalFrameEx (
[email protected]=Frame 0x7fdbe8013350, for file /usr/lib/python2.7/site-packages/urllib3/util/connection.py, line 64, in create_connection (address=('localhost', 8086), timeout=3000, source_address=None, socket_options=[(6, 1, 1)], host='localhost', port=8086, err=None), [email protected]=0) at /usr/src/debug/Python-2.7.5/Python/ceval.c:3040

(gdb) frame 3
#3 0x00007fdbf8e846ea in _nss_files_gethostbyname4_r ([email protected]=0x233fa44 "localhost", [email protected]=0x7fdbecfcb8e0, [email protected]=0x7fdbecfcb340 "hZ \372\333\177",
[email protected]=1064, [email protected]=0x7fdbecfcb8b0, [email protected]=0x7fdbecfcb910, [email protected]=0x0) at nss_files/files-hosts.c:381
381 __libc_lock_lock (lock);
(gdb) list
376 enum nss_status
377 _nss_files_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat,
378 char *buffer, size_t buflen, int *errnop,
379 int *herrnop, int32_t *ttlp)
380 {
381 __libc_lock_lock (lock);
383 /* Reset file pointer to beginning or open file. */
384 enum nss_status status = internal_setent (keep_stream);

Или в превод – опитваме се да вземем стандартния lock, който libc-то използва за да си пази reentrant функциите, и някой го държи. Кой ли?

(gdb) p lock
$3 = {__data = {__lock = 2, __count = 0, __owner = 16609, __nusers = 1, __kind = 0, __spins = 0, __elision = 0, __list = {__prev = 0x0, __next = 0x0}},
__size = "\002\000\000\000\000\000\000\000\[email protected]\000\000\001", '\000' , __align = 2}
(gdb) p &lock
$4 = (__libc_lock_t *) 0x7fdbf908c2c0

Тук се вижда как owner-а на lock-а всъщност е parent-а. Той обаче не смята, че го държи:

(gdb) p lock
$2 = 0
(gdb) p &lock
$3 = (__libc_lock_t *) 0x7fdbf9450df0
(gdb) x/20x 0x7fdbf9450df0
: 0x00000000 0x00000000 0x00000000 0x00000000
0x7fdbf9450e00 <__abort_msg>: 0x00000000 0x00000000 0x00000000 0x00000000
0x7fdbf9450e10 : 0x00000000 0x00000000 0x00000000 0x00000000
0x7fdbf9450e20 : 0x00000000 0x00000000 0x00000000 0x00000000
0x7fdbf9450e30 : 0x001762c9 0x00000000 0x00000000 0x00000000

… което е и съвсем очаквано, при условие, че са два процеса и тая памет не е обща.

Та, явно това, което се е случило е, че докато parent-а е правел fork(), тоя lock го е държал някой, и child-а реално не може да пипне каквото и да е, свързано с него (което значи никакви reentrant функции в glibc-то, каквито па всички ползват (и би трябвало да ползват)). Въпросът е, че по принцип това не би трябвало да е възможно, щото около fork() няма нищо, което да взима тоя lock, и би трябвало glibc да си освобождава lock-а като излиза от функциите си.

Първоначалното ми идиотско предположение беше, че в signal handler-а на SIGCHLD multiprocessing модула създава новите child-ове, и така докато нещо друго държи lock-а идва сигнал, прави се нов процес и той го “наследява” заключен. Това беше твърде глупаво, за да е истина, и се оказа, че не е…

Около въпросите с lock-а бях стигнал с търсене до две неща – issue 127 в gperftools и Debian bug 657835. Първото каза, че проблемът ми може да е от друг lock, който някой друг държи преди fork-а (което ме накара да се загледам по-внимателно какви lock-ове се държат), а второто, че като цяло ако fork-ваш thread-нато приложение, може после единствено да правиш execve(), защото всичко друго не е ясно колко ще работи.

И накрая се оказа, че ако се ползва multiprocessing модула, той пуска в главния процес няколко thread-а, които да се занимават със следенето и пускането на child-ове за обработка. Та ето какво реално се случва:

– някой child си изработва нужния брой операции и излиза
– parent-а получава SIGCHLD и си отбелязва, че трябва да види какво става
– главния thread на parent-а тръгва да събира списъка бази, и вика в някакъв момент _nss_files_gethostbyname4_r, който взима lock-а;
– по това време другия thread казва “а, нямам достатъчно child-ове, fork()”
– profit.

Текущото ми глупаво решение е да не правя нищо в главния thread, което може да взима тоя lock и да се надявам, че няма още някой такъв. Бъдещото ми решение е или да го пиша на python3 с някой друг модул по темата, или на go (което ще трябва да науча).

Scanning snacks to your Wunderlist shopping list with Wunderscan

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/scanning-snacks-to-your-wunderlist-shopping-list/

Brian Carrigan found the remains of a $500 supermarket barcode scanner at a Scrap Exchange for $6.25, and decided to put it to use as a shopping list builder for his pantry.

Raspberry Pi Barcode Scanner Wunderscan Brian Carrigan

Upcycling from scraps

Brian wasn’t planning to build the Wunderscan. But when he stumbled upon the remains of a $500 Cubit barcode scanner at his local reuse center, his inner maker took hold of the situation.

It had been ripped from its connectors and had unlabeled wires hanging from it; a bit of hardware gore if such a thing exists. It was labeled on sale for $6.25, and a quick search revealed that it originally retailed at over $500… I figured I would try to reverse engineer it, and if all else fails, scrap it for the laser and motor.

Brian decided that the scanner, once refurbished with a Raspberry Pi Zero W and new wiring, would make a great addition to his home pantry as a shopping list builder using Wunderlist. “I thought a great use of this would be to keep near our pantry so that when we are out of a spice or snack, we could just scan the item and it would get posted to our shopping list.”

Reverse engineering

The datasheet for the Cubit scanner was available online, and Brian was able to discover the missing pieces required to bring the unit back to working order.

Raspberry Pi Barcode Scanner Wunderscan Brian Carrigan

However, no wiring diagram was provided with the datasheet, so he was forced to figure out the power connections and signal output for himself using a bit of luck and an oscilloscope.

Now that the part was powered and working, all that was left was finding the RS232 transmit line. I used my oscilloscope to do this part and found it by scanning items and looking for the signal. It was not long before this wire was found and I was able to receive UPC codes.

Scanning codes and building (Wunder)lists

When the scanner reads a barcode, it sends the ASCII representation of a UPC code to the attached Raspberry Pi Zero W. Brian used the free UPC Database to convert each code to the name of the corresponding grocery item. Next, he needed to add it to the Wunderlist shopping list that his wife uses for grocery shopping.

Raspberry Pi Barcode Scanner Wunderscan Brian Carrigan

Wunderlist provides an API token so users can incorporate list-making into their projects. With a little extra coding, Brian was able to convert the scanning of a pantry item’s barcode into a new addition to the family shopping list.

Curious as to how it all came together? You can find information on the project, including code and hardware configurations, on Brian’s blog. If you’ve built something similar, we’d love to see it in the comments below.

The post Scanning snacks to your Wunderlist shopping list with Wunderscan appeared first on Raspberry Pi.

No, Ray Ozzie hasn’t solved crypto backdoors

Post Syndicated from Robert Graham original https://blog.erratasec.com/2018/04/no-ray-ozzie-hasnt-solved-crypto.html

According to this Wired article, Ray Ozzie may have a solution to the crypto backdoor problem. No, he hasn’t. He’s only solving the part we already know how to solve. He’s deliberately ignoring the stuff we don’t know how to solve. We know how to make backdoors, we just don’t know how to secure them.

The vault doesn’t scale

Yes, Apple has a vault where they’ve successfully protected important keys. No, it doesn’t mean this vault scales. The more people and the more often you have to touch the vault, the less secure it becomes. We are talking thousands of requests per day from 100,000 different law enforcement agencies around the world. We are unlikely to protect this against incompetence and mistakes. We are definitely unable to secure this against deliberate attack.

A good analogy to Ozzie’s solution is LetsEncrypt for getting SSL certificates for your website, which is fairly scalable, using a private key locked in a vault for signing hundreds of thousands of certificates. That this scales seems to validate Ozzie’s proposal.

But at the same time, LetsEncrypt is easily subverted. LetsEncrypt uses DNS to verify your identity. But spoofing DNS is easy, as was recently shown in the recent BGP attack against a cryptocurrency. Attackers can create fraudulent SSL certificates with enough effort. We’ve got other protections against this, such as discovering and revoking the SSL bad certificate, so while damaging, it’s not catastrophic.

But with Ozzie’s scheme, equivalent attacks would be catastrophic, as it would lead to unlocking the phone and stealing all of somebody’s secrets.

In particular, consider what would happen if LetsEncrypt’s certificate was stolen (as Matthew Green points out). The consequence is that this would be detected and mass revocations would occur. If Ozzie’s master key were stolen, nothing would happen. Nobody would know, and evildoers would be able to freely decrypt phones. Ozzie claims his scheme can work because SSL works — but then his scheme includes none of the many protections necessary to make SSL work.

What I’m trying to show here is that in a lab, it all looks nice and pretty, but when attacked at scale, things break down — quickly. We have so much experience with failure at scale that we can judge Ozzie’s scheme as woefully incomplete. It’s not even up to the standard of SSL, and we have a long list of SSL problems.

Cryptography is about people more than math

We have a mathematically pure encryption algorithm called the “One Time Pad”. It can’t ever be broken, provably so with mathematics.

It’s also perfectly useless, as it’s not something humans can use. That’s why we use AES, which is vastly less secure (anything you encrypt today can probably be decrypted in 100 years). AES can be used by humans whereas One Time Pads cannot be. (I learned the fallacy of One Time Pad’s on my grandfather’s knee — he was a WW II codebreaker who broke German messages trying to futz with One Time Pads).

The same is true with Ozzie’s scheme. It focuses on the mathematical model but ignores the human element. We already know how to solve the mathematical problem in a hundred different ways. The part we don’t know how to secure is the human element.

How do we know the law enforcement person is who they say they are? How do we know the “trusted Apple employee” can’t be bribed? How can the law enforcement agent communicate securely with the Apple employee?

You think these things are theoretical, but they aren’t. Consider financial transactions. It used to be common that you could just email your bank/broker to wire funds into an account for such things as buying a house. Hackers have subverted that, intercepting messages, changing account numbers, and stealing millions. Most banks/brokers require additional verification before doing such transfers.

Let me repeat: Ozzie has only solved the part we already know how to solve. He hasn’t addressed these issues that confound us.

We still can’t secure security, much less secure backdoors

We already know how to decrypt iPhones: just wait a year or two for somebody to discover a vulnerability. FBI claims it’s “going dark”, but that’s only for timely decryption of phones. If they are willing to wait a year or two a vulnerability will eventually be found that allows decryption.

That’s what’s happened with the “GrayKey” device that’s been all over the news lately. Apple is fixing it so that it won’t work on new phones, but it works on old phones.

Ozzie’s solution is based on the assumption that iPhones are already secure against things like GrayKey. Like his assumption “if Apple already has a vault for private keys, then we have such vaults for backdoor keys”, Ozzie is saying “if Apple already had secure hardware/software to secure the phone, then we can use the same stuff to secure the backdoors”. But we don’t really have secure vaults and we don’t really have secure hardware/software to secure the phone.

Again, to stress this point, Ozzie is solving the part we already know how to solve, but ignoring the stuff we don’t know how to solve. His solution is insecure for the same reason phones are already insecure.

Locked phones aren’t the problem

Phones are general purpose computers. That means anybody can install an encryption app on the phone regardless of whatever other security the phone might provide. The police are powerless to stop this. Even if they make such encryption crime, then criminals will still use encryption.

That leads to a strange situation that the only data the FBI will be able to decrypt is that of people who believe they are innocent. Those who know they are guilty will install encryption apps like Signal that have no backdoors.

In the past this was rare, as people found learning new apps a barrier. These days, apps like Signal are so easy even drug dealers can figure out how to use them.

We know how to get Apple to give us a backdoor, just pass a law forcing them to. It may look like Ozzie’s scheme, it may be something more secure designed by Apple’s engineers. Sure, it will weaken security on the phone for everyone, but those who truly care will just install Signal. But again we are back to the problem that Ozzie’s solving the problem we know how to solve while ignoring the much larger problem, that of preventing people from installing their own encryption.

The FBI isn’t necessarily the problem

Ozzie phrases his solution in terms of U.S. law enforcement. Well, what about Europe? What about Russia? What about China? What about North Korea?

Technology is borderless. A solution in the United States that allows “legitimate” law enforcement requests will inevitably be used by repressive states for what we believe would be “illegitimate” law enforcement requests.

Ozzie sees himself as the hero helping law enforcement protect 300 million American citizens. He doesn’t see himself what he really is, the villain helping oppress 1.4 billion Chinese, 144 million Russians, and another couple billion living in oppressive governments around the world.


Ozzie pretends the problem is political, that he’s created a solution that appeases both sides. He hasn’t. He’s solved the problem we already know how to solve. He’s ignored all the problems we struggle with, the problems we claim make secure backdoors essentially impossible. I’ve listed some in this post, but there are many more. Any famous person can create a solution that convinces fawning editors at Wired Magazine, but if Ozzie wants to move forward he’s going to have to work harder to appease doubting cryptographers.

Russia is Banning Telegram

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2018/04/russia_is_banni.html

Russia has banned the secure messaging app Telegram. It’s making an absolute mess of the ban — blocking 16 million IP addresses, many belonging to the Amazon and Google clouds — and it’s not even clear that it’s working. But, more importantly, I’m not convinced Telegram is secure in the first place.

Such a weird story. If you want secure messaging, use Signal. If you’re concerned that having Signal on your phone will itself arouse suspicion, use WhatsApp.

Implementing safe AWS Lambda deployments with AWS CodeDeploy

Post Syndicated from Chris Munns original https://aws.amazon.com/blogs/compute/implementing-safe-aws-lambda-deployments-with-aws-codedeploy/

This post courtesy of George Mao, AWS Senior Serverless Specialist – Solutions Architect

AWS Lambda and AWS CodeDeploy recently made it possible to automatically shift incoming traffic between two function versions based on a preconfigured rollout strategy. This new feature allows you to gradually shift traffic to the new function. If there are any issues with the new code, you can quickly rollback and control the impact to your application.

Previously, you had to manually move 100% of traffic from the old version to the new version. Now, you can have CodeDeploy automatically execute pre- or post-deployment tests and automate a gradual rollout strategy. Traffic shifting is built right into the AWS Serverless Application Model (SAM), making it easy to define and deploy your traffic shifting capabilities. SAM is an extension of AWS CloudFormation that provides a simplified way of defining serverless applications.

In this post, I show you how to use SAM, CloudFormation, and CodeDeploy to accomplish an automated rollout strategy for safe Lambda deployments.


For this walkthrough, you write a Lambda application that returns a count of the S3 buckets that you own. You deploy it and use it in production. Later on, you receive requirements that tell you that you need to change your Lambda application to count only buckets that begin with the letter “a”.

Before you make the change, you need to be sure that your new Lambda application works as expected. If it does have issues, you want to minimize the number of impacted users and roll back easily. To accomplish this, you create a deployment process that publishes the new Lambda function, but does not send any traffic to it. You use CodeDeploy to execute a PreTraffic test to ensure that your new function works as expected. After the test succeeds, CodeDeploy automatically shifts traffic gradually to the new version of the Lambda function.

Your Lambda function is exposed as a REST service via an Amazon API Gateway deployment. This makes it easy to test and integrate.


To execute the SAM and CloudFormation deployment, you must have the following IAM permissions:

  • cloudformation:*
  • lambda:*
  • codedeploy:*
  • iam:create*

You may use the AWS SAM Local CLI or the AWS CLI to package and deploy your Lambda application. If you choose to use SAM Local, be sure to install it onto your system. For more information, see AWS SAM Local Installation.

All of the code used in this post can be found in this GitHub repository: https://github.com/aws-samples/aws-safe-lambda-deployments.


For this post, use SAM to define your resources because it comes with built-in CodeDeploy support for safe Lambda deployments.  The deployment is handled and automated by CloudFormation.

SAM allows you to define your Serverless applications in a simple and concise fashion, because it automatically creates all necessary resources behind the scenes. For example, if you do not define an execution role for a Lambda function, SAM automatically creates one. SAM also creates the CodeDeploy application necessary to drive the traffic shifting, as well as the IAM service role that CodeDeploy uses to execute all actions.

Create a SAM template

To get started, write your SAM template and call it template.yaml.

AWSTemplateFormatVersion : '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: An example SAM template for Lambda Safe Deployments.


    Type: AWS::Serverless::Function
      Handler: returnS3Buckets.handler
      Runtime: nodejs6.10
      AutoPublishAlias: live
        - Version: "2012-10-17"
          - Effect: "Allow"
              - "s3:ListAllMyBuckets"
            Resource: '*'
          Type: Linear10PercentEvery1Minute
            PreTraffic: !Ref preTrafficHook
          Type: Api
            Path: /test
            Method: get

    Type: AWS::Serverless::Function
      Handler: preTrafficHook.handler
        - Version: "2012-10-17"
          - Effect: "Allow"
              - "codedeploy:PutLifecycleEventHookExecutionStatus"
              !Sub 'arn:aws:codedeploy:${AWS::Region}:${AWS::AccountId}:deploymentgroup:${ServerlessDeploymentApplication}/*'
        - Version: "2012-10-17"
          - Effect: "Allow"
              - "lambda:InvokeFunction"
            Resource: !Ref returnS3Buckets.Version
      Runtime: nodejs6.10
      FunctionName: 'CodeDeployHook_preTrafficHook'
        Enabled: false
      Timeout: 5
          NewVersion: !Ref returnS3Buckets.Version

This template creates two functions:

  • returnS3Buckets
  • preTrafficHook

The returnS3Buckets function is where your application logic lives. It’s a simple piece of code that uses the AWS SDK for JavaScript in Node.JS to call the Amazon S3 listBuckets API action and return the number of buckets.

'use strict';

var AWS = require('aws-sdk');
var s3 = new AWS.S3();

exports.handler = (event, context, callback) => {
	console.log("I am here! " + context.functionName  +  ":"  +  context.functionVersion);

	s3.listBuckets(function (err, data){
			console.log(err, err.stack);
			callback(null, {
				statusCode: 500,
				body: "Failed!"
			var allBuckets = data.Buckets;

			console.log("Total buckets: " + allBuckets.length);
			callback(null, {
				statusCode: 200,
				body: allBuckets.length

Review the key parts of the SAM template that defines returnS3Buckets:

  • The AutoPublishAlias attribute instructs SAM to automatically publish a new version of the Lambda function for each new deployment and link it to the live alias.
  • The Policies attribute specifies additional policy statements that SAM adds onto the automatically generated IAM role for this function. The first statement provides the function with permission to call listBuckets.
  • The DeploymentPreference attribute configures the type of rollout pattern to use. In this case, you are shifting traffic in a linear fashion, moving 10% of traffic every minute to the new version. For more information about supported patterns, see Serverless Application Model: Traffic Shifting Configurations.
  • The Hooks attribute specifies that you want to execute the preTrafficHook Lambda function before CodeDeploy automatically begins shifting traffic. This function should perform validation testing on the newly deployed Lambda version. This function invokes the new Lambda function and checks the results. If you’re satisfied with the tests, instruct CodeDeploy to proceed with the rollout via an API call to: codedeploy.putLifecycleEventHookExecutionStatus.
  • The Events attribute defines an API-based event source that can trigger this function. It accepts requests on the /test path using an HTTP GET method.
'use strict';

const AWS = require('aws-sdk');
const codedeploy = new AWS.CodeDeploy({apiVersion: '2014-10-06'});
var lambda = new AWS.Lambda();

exports.handler = (event, context, callback) => {

	console.log("Entering PreTraffic Hook!");
	// Read the DeploymentId & LifecycleEventHookExecutionId from the event payload
    var deploymentId = event.DeploymentId;
	var lifecycleEventHookExecutionId = event.LifecycleEventHookExecutionId;

	var functionToTest = process.env.NewVersion;
	console.log("Testing new function version: " + functionToTest);

	// Perform validation of the newly deployed Lambda version
	var lambdaParams = {
		FunctionName: functionToTest,
		InvocationType: "RequestResponse"

	var lambdaResult = "Failed";
	lambda.invoke(lambdaParams, function(err, data) {
		if (err){	// an error occurred
			console.log(err, err.stack);
			lambdaResult = "Failed";
		else{	// successful response
			var result = JSON.parse(data.Payload);
			console.log("Result: " +  JSON.stringify(result));

			// Check the response for valid results
			// The response will be a JSON payload with statusCode and body properties. ie:
			// {
			//		"statusCode": 200,
			//		"body": 51
			// }
			if(result.body == 9){	
				lambdaResult = "Succeeded";
				console.log ("Validation testing succeeded!");
				lambdaResult = "Failed";
				console.log ("Validation testing failed!");

			// Complete the PreTraffic Hook by sending CodeDeploy the validation status
			var params = {
				deploymentId: deploymentId,
				lifecycleEventHookExecutionId: lifecycleEventHookExecutionId,
				status: lambdaResult // status can be 'Succeeded' or 'Failed'
			// Pass AWS CodeDeploy the prepared validation test results.
			codedeploy.putLifecycleEventHookExecutionStatus(params, function(err, data) {
				if (err) {
					// Validation failed.
					console.log('CodeDeploy Status update failed');
					console.log(err, err.stack);
					callback("CodeDeploy Status update failed");
				} else {
					// Validation succeeded.
					console.log('Codedeploy status updated successfully');
					callback(null, 'Codedeploy status updated successfully');

The hook is hardcoded to check that the number of S3 buckets returned is 9.

Review the key parts of the SAM template that defines preTrafficHook:

  • The Policies attribute specifies additional policy statements that SAM adds onto the automatically generated IAM role for this function. The first statement provides permissions to call the CodeDeploy PutLifecycleEventHookExecutionStatus API action. The second statement provides permissions to invoke the specific version of the returnS3Buckets function to test
  • This function has traffic shifting features disabled by setting the DeploymentPreference option to false.
  • The FunctionName attribute explicitly tells CloudFormation what to name the function. Otherwise, CloudFormation creates the function with the default naming convention: [stackName]-[FunctionName]-[uniqueID].  Name the function with the “CodeDeployHook_” prefix because the CodeDeployServiceRole role only allows InvokeFunction on functions named with that prefix.
  • Set the Timeout attribute to allow enough time to complete your validation tests.
  • Use an environment variable to inject the ARN of the newest deployed version of the returnS3Buckets function. The ARN allows the function to know the specific version to invoke and perform validation testing on.

Deploy the function

Your SAM template is all set and the code is written—you’re ready to deploy the function for the first time. Here’s how to do it via the SAM CLI. Replace “sam” with “cloudformation” to use CloudFormation instead.

First, package the function. This command returns a CloudFormation importable file, packaged.yaml.

sam package –template-file template.yaml –s3-bucket mybucket –output-template-file packaged.yaml

Now deploy everything:

sam deploy –template-file packaged.yaml –stack-name mySafeDeployStack –capabilities CAPABILITY_IAM

At this point, both Lambda functions have been deployed within the CloudFormation stack mySafeDeployStack. The returnS3Buckets has been deployed as Version 1:

SAM automatically created a few things, including the CodeDeploy application, with the deployment pattern that you specified (Linear10PercentEvery1Minute). There is currently one deployment group, with no action, because no deployments have occurred. SAM also created the IAM service role that this CodeDeploy application uses:

There is a single managed policy attached to this role, which allows CodeDeploy to invoke any Lambda function that begins with “CodeDeployHook_”.

An API has been set up called safeDeployStack. It targets your Lambda function with the /test resource using the GET method. When you test the endpoint, API Gateway executes the returnS3Buckets function and it returns the number of S3 buckets that you own. In this case, it’s 51.

Publish a new Lambda function version

Now implement the requirements change, which is to make returnS3Buckets count only buckets that begin with the letter “a”. The code now looks like the following (see returnS3BucketsNew.js in GitHub):

'use strict';

var AWS = require('aws-sdk');
var s3 = new AWS.S3();

exports.handler = (event, context, callback) => {
	console.log("I am here! " + context.functionName  +  ":"  +  context.functionVersion);

	s3.listBuckets(function (err, data){
			console.log(err, err.stack);
			callback(null, {
				statusCode: 500,
				body: "Failed!"
			var allBuckets = data.Buckets;

			console.log("Total buckets: " + allBuckets.length);
			//callback(null, allBuckets.length);

			//  New Code begins here
			var counter=0;
			for(var i  in allBuckets){
				if(allBuckets[i].Name[0] === "a")
			console.log("Total buckets starting with a: " + counter);

			callback(null, {
				statusCode: 200,
				body: counter

Repackage and redeploy with the same two commands as earlier:

sam package –template-file template.yaml –s3-bucket mybucket –output-template-file packaged.yaml
sam deploy –template-file packaged.yaml –stack-name mySafeDeployStack –capabilities CAPABILITY_IAM

CloudFormation understands that this is a stack update instead of an entirely new stack. You can see that reflected in the CloudFormation console:

During the update, CloudFormation deploys the new Lambda function as version 2 and adds it to the “live” alias. There is no traffic routing there yet. CodeDeploy now takes over to begin the safe deployment process.

The first thing CodeDeploy does is invoke the preTrafficHook function. Verify that this happened by reviewing the Lambda logs and metrics:

The function should progress successfully, invoke Version 2 of returnS3Buckets, and finally invoke the CodeDeploy API with a success code. After this occurs, CodeDeploy begins the predefined rollout strategy. Open the CodeDeploy console to review the deployment progress (Linear10PercentEvery1Minute):

Verify the traffic shift

During the deployment, verify that the traffic shift has started to occur by running the test periodically. As the deployment shifts towards the new version, a larger percentage of the responses return 9 instead of 51. These numbers match the S3 buckets.

A minute later, you see 10% more traffic shifting to the new version. The whole process takes 10 minutes to complete. After completion, open the Lambda console and verify that the “live” alias now points to version 2:

After 10 minutes, the deployment is complete and CodeDeploy signals success to CloudFormation and completes the stack update.

Check the results

If you invoke the function alias manually, you see the results of the new implementation.

aws lambda invoke –function [lambda arn to live alias] out.txt

You can also execute the prod stage of your API and verify the results by issuing an HTTP GET to the invoke URL:


This post has shown you how you can safely automate your Lambda deployments using the Lambda traffic shifting feature. You used the Serverless Application Model (SAM) to define your Lambda functions and configured CodeDeploy to manage your deployment patterns. Finally, you used CloudFormation to automate the deployment and updates to your function and PreTraffic hook.

Now that you know all about this new feature, you’re ready to begin automating Lambda deployments with confidence that things will work as designed. I look forward to hearing about what you’ve built with the AWS Serverless Platform.

Colour sensing with a Raspberry Pi

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/colour-sensing-raspberry-pi/

In their latest video and tutorial, Electronic Hub shows you how to detect colour using a Raspberry Pi and a TCS3200 colour sensor.

Raspberry Pi Color Sensor (TCS3200) Interface | Color Detector

A simple Raspberry Pi based project using TCS3200 Color Sensor. The project demonstrates how to interface a Color Sensor (like TCS3200) with Raspberry Pi and implement a simple Color Detector using Raspberry Pi.

What is a TCS3200 colour sensor?

Colour sensors sense reflected light from nearby objects. The bright light of the TCS3200’s on-board white LEDs hits an object’s surface and is reflected back. The sensor has an 8×8 array of photodiodes, which are covered by either a red, blue, green, or clear filter. The type of filter determines what colour a diode can detect. Then the overall colour of an object is determined by how much light of each colour it reflects. (For example, a red object reflects mostly red light.)

Colour sensing with the TCS3200 Color Sensor and a Raspberry Pi

As Electronics Hub explains:

TCS3200 is one of the easily available colour sensors that students and hobbyists can work on. It is basically a light-to-frequency converter, i.e. based on colour and intensity of the light falling on it, the frequency of its output signal varies.

I’ll save you a physics lesson here, but you can find a detailed explanation of colour sensing and the TCS3200 on the Electronics Hub blog.

Raspberry Pi colour sensor

The TCS3200 colour sensor is connected to several of the onboard General Purpose Input Output (GPIO) pins on the Raspberry Pi.

Colour sensing with the TCS3200 Color Sensor and a Raspberry Pi

These connections allow the Raspberry Pi 3 to run one of two Python scripts that Electronics Hub has written for the project. The first displays the RAW RGB values read by the sensor. The second detects the primary colours red, green, and blue, and it can be expanded for more colours with the help of the first script.

Colour sensing with the TCS3200 Color Sensor and a Raspberry Pi

Electronic Hub’s complete build uses a breadboard for simply prototyping

Use it in your projects

This colour sensing setup is a simple means of adding a new dimension to your builds. Why not build a candy-sorting robot that organises your favourite sweets by colour? Or add colour sensing to your line-following buggy to allow for multiple path options!

If your Raspberry Pi project uses colour sensing, we’d love to see it, so be sure to share it in the comments!

The post Colour sensing with a Raspberry Pi appeared first on Raspberry Pi.

Using AWS Lambda and Amazon Comprehend for sentiment analysis

Post Syndicated from Chris Munns original https://aws.amazon.com/blogs/compute/using-aws-lambda-and-amazon-comprehend-for-sentiment-analysis/

This post courtesy of Giedrius Praspaliauskas, AWS Solutions Architect

Even with best IVR systems, customers get frustrated. What if you knew that 10 callers in your Amazon Connect contact flow were likely to say “Agent!” in frustration in the next 30 seconds? Would you like to get to them before that happens? What if your bot was smart enough to admit, “I’m sorry this isn’t helping. Let me find someone for you.”?

In this post, I show you how to use AWS Lambda and Amazon Comprehend for sentiment analysis to make your Amazon Lex bots in Amazon Connect more sympathetic.

Setting up a Lambda function for sentiment analysis

There are multiple natural language and text processing frameworks or services available to use with Lambda, including but not limited to Amazon Comprehend, TextBlob, Pattern, and NLTK. Pick one based on the nature of your system:  the type of interaction, languages supported, and so on. For this post, I picked Amazon Comprehend, which uses natural language processing (NLP) to extract insights and relationships in text.

The walkthrough in this post is just an example. In a full-scale implementation, you would likely implement a more nuanced approach. For example, you could keep the overall sentiment score through the conversation and act only when it reaches a certain threshold. It is worth noting that this Lambda function is not called for missed utterances, so there may be a gap between what is being analyzed and what was actually said.

The Lambda function is straightforward. It analyses the input transcript field of the Amazon Lex event. Based on the overall sentiment value, it generates a response message with next step instructions. When the sentiment is neutral, positive, or mixed, the response leaves it to Amazon Lex to decide what the next steps should be. It adds to the response overall sentiment value as an additional session attribute, along with slots’ values received as an input.

When the overall sentiment is negative, the function returns the dialog action, pointing to an escalation intent (specified in the environment variable ESCALATION_INTENT_NAME) or returns the fulfillment closure action with a failure state when the intent is not specified. In addition to actions or intents, the function returns a message, or prompt, to be provided to the customer before taking the next step. Based on the returned action, Amazon Connect can select the appropriate next step in a contact flow.

For this walkthrough, you create a Lambda function using the AWS Management Console:

  1. Open the Lambda console.
  2. Choose Create Function.
  3. Choose Author from scratch (no blueprint).
  4. For Runtime, choose Python 3.6.
  5. For Role, choose Create a custom role. The custom execution role allows the function to detect sentiments, create a log group, stream log events, and store the log events.
  6. Enter the following values:
    • For Role Description, enter Lambda execution role permissions.
    • For IAM Role, choose Create an IAM role.
    • For Role Name, enter LexSentimentAnalysisLambdaRole.
    • For Policy, use the following policy:
    "Version": "2012-10-17",
    "Statement": [
            "Effect": "Allow",
            "Action": [
            "Resource": "arn:aws:logs:*:*:*"
            "Action": [
            "Effect": "Allow",
            "Resource": "*"
    1. Choose Create function.
    2. Copy/paste the following code to the editor window
import os, boto3

ESCALATION_INTENT_MESSAGE="Seems that you are having troubles with our service. Would you like to be transferred to the associate?"
FULFILMENT_CLOSURE_MESSAGE="Seems that you are having troubles with our service. Let me transfer you to the associate."

escalation_intent_name = os.getenv('ESACALATION_INTENT_NAME', None)

client = boto3.client('comprehend')

def lambda_handler(event, context):
    if sentiment=='NEGATIVE':
        if escalation_intent_name:
            result = {
                "sessionAttributes": {
                    "sentiment": sentiment
                    "dialogAction": {
                        "type": "ConfirmIntent", 
                        "message": {
                            "contentType": "PlainText", 
                            "content": ESCALATION_INTENT_MESSAGE
                    "intentName": escalation_intent_name
            result = {
                "sessionAttributes": {
                    "sentiment": sentiment
                "dialogAction": {
                    "type": "Close",
                    "fulfillmentState": "Failed",
                    "message": {
                            "contentType": "PlainText",
                            "content": FULFILMENT_CLOSURE_MESSAGE

        result ={
            "sessionAttributes": {
                "sentiment": sentiment
            "dialogAction": {
                "type": "Delegate",
                "slots" : event["currentIntent"]["slots"]
    return result
  1. Below the code editor specify the environment variable ESCALATION_INTENT_NAME with a value of Escalate.

  1. Click on Save in the top right of the console.

Now you can test your function.

  1. Click Test at the top of the console.
  2. Configure a new test event using the following test event JSON:
  "messageVersion": "1.0",
  "invocationSource": "DialogCodeHook",
  "userId": "1234567890",
  "sessionAttributes": {},
  "bot": {
    "name": "BookSomething",
    "alias": "None",
    "version": "$LATEST"
  "outputDialogMode": "Text",
  "currentIntent": {
    "name": "BookSomething",
    "slots": {
      "slot1": "None",
      "slot2": "None"
    "confirmationStatus": "None"
  "inputTranscript": "I want something"
  1. Click Create
  2. Click Test on the console

This message should return a response from Lambda with a sentiment session attribute of NEUTRAL.

However, if you change the input to “This is garbage!”, Lambda changes the dialog action to the escalation intent specified in the environment variable ESCALATION_INTENT_NAME.

Setting up Amazon Lex

Now that you have your Lambda function running, it is time to create the Amazon Lex bot. Use the BookTrip sample bot and call it BookSomething. The IAM role is automatically created on your behalf. Indicate that this bot is not subject to the COPPA, and choose Create. A few minutes later, the bot is ready.

Make the following changes to the default configuration of the bot:

  1. Add an intent with no associated slots. Name it Escalate.
  2. Specify the Lambda function for initialization and validation in the existing two intents (“BookCar” and “BookHotel”), at the same time giving Amazon Lex permission to invoke it.
  3. Leave the other configuration settings as they are and save the intents.

You are ready to build and publish this bot. Set a new alias, BookSomethingWithSentimentAnalysis. When the build finishes, test it.

As you see, sentiment analysis works!

Setting up Amazon Connect

Next, provision an Amazon Connect instance.

After the instance is created, you need to integrate the Amazon Lex bot created in the previous step. For more information, see the Amazon Lex section in the Configuring Your Amazon Connect Instance topic.  You may also want to look at the excellent post by Randall Hunt, New – Amazon Connect and Amazon Lex Integration.

Create a new contact flow, “Sentiment analysis walkthrough”:

  1. Log in into the Amazon Connect instance.
  2. Choose Create contact flow, Create transfer to agent flow.
  3. Add a Get customer input block, open the icon in the top left corner, and specify your Amazon Lex bot and its intents.
  4. Select the Text to speech audio prompt type and enter text for Amazon Connect to play at the beginning of the dialog.
  5. Choose Amazon Lex, enter your Amazon Lex bot name and the alias.
  6. Specify the intents to be used as dialog branches that a customer can choose: BookHotel, BookTrip, or Escalate.
  7. Add two Play prompt blocks and connect them to the customer input block.
    • If booking hotel or car intent is returned from the bot flow, play the corresponding prompt (“OK, will book it for you”) and initiate booking (in this walkthrough, just hang up after the prompt).
    • However, if escalation intent is returned (caused by the sentiment analysis results in the bot), play the prompt (“OK, transferring to an agent”) and initiate the transfer.
  8. Save and publish the contact flow.

As a result, you have a contact flow with a single customer input step and a text-to-speech prompt that uses the Amazon Lex bot. You expect one of the three intents returned:

Edit the phone number to associate the contact flow that you just created. It is now ready for testing. Call the phone number and check how your contact flow works.


Don’t forget to delete all the resources created during this walkthrough to avoid incurring any more costs:

  • Amazon Connect instance
  • Amazon Lex bot
  • Lambda function
  • IAM role LexSentimentAnalysisLambdaRole


In this walkthrough, you implemented sentiment analysis with a Lambda function. The function can be integrated into Amazon Lex and, as a result, into Amazon Connect. This approach gives you the flexibility to analyze user input and then act. You may find the following potential use cases of this approach to be of interest:

  • Extend the Lambda function to identify “hot” topics in the user input even if the sentiment is not negative and take action proactively. For example, switch to an escalation intent if a user mentioned “where is my order,” which may signal potential frustration.
  • Use Amazon Connect Streams to provide agent sentiment analysis results along with call transfer. Enable service tailored towards particular customer needs and sentiments.
  • Route calls to agents based on both skill set and sentiment.
  • Prioritize calls based on sentiment using multiple Amazon Connect queues instead of transferring directly to an agent.
  • Monitor quality and flag for review contact flows that result in high overall negative sentiment.
  • Implement sentiment and AI/ML based call analysis, such as a real-time recommendation engine. For more details, see Machine Learning on AWS.

If you have questions or suggestions, please comment below.

Safety first: a Raspberry Pi safety helmet

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/safety-helmet/

Jennifer Fox is back, this time with a Raspberry Pi Zero–controlled impact force monitor that will notify you if your collision is a worth a trip to the doctor.

Make an Impact Force Monitor!

Check out my latest Hacker in Residence project for SparkFun Electronics: the Helmet Guardian! It’s a Pi Zero powered impact force monitor that turns on an LED if your head/body experiences a potentially dangerous impact. Install in your sports helmets, bicycle, or car to keep track of impact and inform you when it’s time to visit the doctor.


We’ve all knocked our heads at least once in our lives, maybe due to tripping over a loose paving slab, or to falling off a bike, or to walking into the corner of the overhead cupboard door for the third time this week — will I ever learn?! More often than not, even when we’re seeing stars, we brush off the accident and continue with our day, oblivious to the long-term damage we may be doing.

Force of impact

After some thorough research, Jennifer Fox, founder of FoxBot Industries, concluded that forces of 4 to 6 G sustained for more than a few seconds are dangerous to the human body. With this in mind, she decided to use a Raspberry Pi Zero W and an accelerometer to create helmet with an impact force monitor that notifies its wearer if this level of G-force has been met.

Jennifer Fox Raspberry Pi Impact Force Monitor

Obviously, if you do have a serious fall, you should always seek medical advice. This project is an example of how affordable technology can be used to create medical and citizen science builds, and not a replacement for professional medical services.

Setting up the impact monitor

Jennifer’s monitor requires only a few pieces of tech: a Zero W, an accelerometer and breakout board, a rechargeable USB battery, and an LED, plus the standard wires and resistors for these components.

After installing Raspbian, Jennifer enabled SSH and I2C on the Zero W to make it run headlessly, and then accessed it from a laptop. This allows her to control the Pi without physically connecting to it, and it makes for a wireless finished project.

Jen wired the Pi to the accelerometer breakout board and LED as shown in the schematic below.

Jennifer Fox Raspberry Pi Impact Force Monitor

The LED acts as a signal of significant impacts, turning on when the G-force threshold is reached, and not turning off again until the program is reset.

Jennifer Fox Raspberry Pi Impact Force Monitor

Make your own and more

Jennifer’s full code for the impact monitor is on GitHub, and she’s put together a complete tutorial on SparkFun’s website.

For more tutorials from Jennifer Fox, such as her ‘Bark Back’ IoT Pet Monitor, be sure to follow her on YouTube. And for similar projects, check out Matt’s smart bike light and Amelia Day’s physical therapy soccer ball.

The post Safety first: a Raspberry Pi safety helmet appeared first on Raspberry Pi.

Newly released guide provides Australian public sector the ability to evaluate AWS at PROTECTED level

Post Syndicated from Oliver Bell original https://aws.amazon.com/blogs/security/newly-released-guide-provides-australian-public-sector-the-ability-to-evaluate-aws-at-protected-level/

Australian public sector customers now have a clear roadmap to use our secure services for sensitive workloads at the PROTECTED level. For the first time, we’ve released our Information Security Registered Assessors Program (IRAP) PROTECTED documentation via AWS Artifact. This information provides the ability to plan, architect, and self-assess systems built in AWS under the Digital Transformation Agency’s Secure Cloud Guidelines.

In short, this documentation gives public sector customers everything needed to evaluate AWS at the PROTECTED level. And we’re making this resource available to download on-demand through AWS Artifact. When you download the guide, you’ll find a mapping of how AWS meets each requirement to securely and compliantly process PROTECTED data.

With the AWS IRAP PROTECTED documentation, the process of adopting our secure services has never been easier. The information enables individual agencies to complete their own assessments and adopt AWS, but we also continue to work with the Australian Signals Directorate to include our services at the PROTECTED level on the Certified Cloud Services List.

Meanwhile, we’re also excited to announce that there are now 46 services in scope, which mean more options to build secure and innovative solutions, while also saving money and gaining the productivity of the cloud.

If you have questions about this announcement or would like to inquire about how to use AWS for your regulated workloads, contact your account team.