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IDA 免費版

Update:被 comment 提醒,找了一下資料,看起來有段歷史了,所以說 RetDec 的影響就未必是這樣了。下面的文章內容就不修正了...:「IDA Support: Evaluation Version」。

IDA 居然也提供免費版了,雖然是比較舊的版本,而且不提供技術支援:「IDA Support: Freeware Version」。IDA 是個可以反組譯以及當 debugger 的工具:

IDA is a Windows, Linux or Mac OS X hosted multi-processor disassembler and debugger that offers so many features it is hard to describe them all. Just grab an evaluation version if you want a test drive.

我猜是 Avast 放出 MIT 授權版本的 RetDec 的關係 (參考「Avast 放出他們的 Decompiler,RetDec」這篇),導致 IDA 這邊要做一些動作推廣試用...

不過我覺得有了 open source 的工具後,會看到 open source 工具慢慢成長...

Twitter 放出來的 Vireo,一套 Open Source 授權的 Video Processing Library

Twitter 放出 Vireo,一套以 MIT License 釋出的 Video Processing Library:「Introducing Vireo: A Lightweight and Versatile Video Processing Library」。專案庫在 GitHubtwitter/vireo 可以取得。

C++ 寫的,另外也已經提供 Scala 的接口,這應該是讓 Twitter 的人可以方便使用:

Vireo is a lightweight and versatile video processing library that powers our video transcoding service, deep learning recognition systems and more. It is written in C++11 and built with functional programming principles. It also optionally comes with Scala wrappers that enable us to build scalable video processing applications within our backend services.

在 Tools 的部份也可以看到很多功能,像是:

thumbnails: extracts keyframes from the input video and saves them as JPG images

viddiff: checks if two video files are functionally identical or not (does not compare data that does not affect the playback behavior)

另外要注意的是,預設不會將 GPL 的套件納入編譯,需要指定 --enable-gpl 才會編進去:

The following libraries are disabled by default. To enable GPL licensed components, they have to be present in your system and --enable-gpl flag have to be explicitly passed to configure

看起來主要就是最常見的那包... (libavformat / libavcodec / libavutil / libswscale / libx264)

Avast 放出他們的 Decompiler,RetDec

AvastMIT License 放出他們的 Decompiler,叫做 RetDec:「Avast open-sources its machine-code decompiler」,專案在 GitHub 上的 avast-tl/retdec 這邊。

Decompiler,也就是直接把 machine code 試著轉回高階語言的程式碼:

這對於分析工作來說簡化很多,尤其是在資安產業的人... 以往比較常見是轉成 assembly 再用人工分析,現在這樣有機會讓大腦輕鬆一些。

雖然目前有些限制 (像是 32 bits only),不過 open source 出來後,可以預料會有不少人開始加功能進去:

  • Supported file formats: ELF, PE, Mach-O, COFF, AR (archive), Intel HEX, and raw machine code.
  • Supported architectures (32b only): Intel x86, ARM, MIPS, PIC32, and PowerPC.


MIT Media Lab 弄出個好玩的東西,可以不打開書直接掃描書的內容:「Can computers read through a book page by page without opening it?」,主標題是「Terahertz time-gated spectral imaging for content extraction through layered structures」。

用 100Ghz 到 3Thz 的電磁波掃描:

In our new study we explore a range of frequencies from 100 Gigahertz to 3 Terahertz (THz) which can penetrate through paper and many other materials.

先前也有類似的方法,用 X-ray 或是超音波,但效果都不好:

Can’t X-ray or ultrasound do this? It may seem that X-ray or ultrasound can also image through a book; however, such techniques lack the contrast of our THz approach for submicron pen or pencil layers compared next to blank paper. These methods have additional drawbacks like cost and ionizing radiation. So while you might be able to hardly detect pages of a closed book if you use a CT scan, you will not be able to see the text. Ultrasound does not have the resolution to detect 20 micron gaps in between the pages of a closed book -distinguishing the ink layers from the blank paper is out of the question for ultrasound. Based on the paper absorption spectrum, we believe that far infrared time resolved systems and THz time domain systems might be the only suitable candidates for investigating paper stacks page by page.


FreeBSD 10 的改變...

Zite 上看到 FreeBSD 10 的改變:「FreeBSD 10's New Technologies and Features」。

最耀眼的當然是對 GCC 的宣戰達到高潮,第一個將預設編譯器換掉的 major release。同樣的,也把 GNU 的 libstdc++ 換成 MIT license 實作的 libc++。

再來是 ISCBIND 被換掉,改用 Unbound 以及 LDNS

然後 UFS 檔案系統可以透過 growfs(8) 線上長大... XDDD

其他的改善包括了 iSCSI stack 重寫,PF 防火牆可以善用 SMP 資源,以及 ZFS 的更新。等正式出版後應該還是會等到 10.1 再上 production 吧?感覺 compiler 一換不知道會有多少雷啊 XD