1 00:00:00,350 --> 00:00:02,960 In the traditional software development model. 2 00:00:02,960 --> 00:00:09,080 Compilers, assemblers and linkers are used to create executable programs. 3 00:00:09,530 --> 00:00:19,040 To reverse engineer these programs, we utilize tools known as Disassemblers and decompilers. 4 00:00:19,490 --> 00:00:27,320 This assemblers reverse the assembly process producing assembler language as output based on machine 5 00:00:27,320 --> 00:00:28,520 language input. 6 00:00:29,180 --> 00:00:38,210 On the other hand, the compilers aim to generate high level language code such as C, Python or Java 7 00:00:38,240 --> 00:00:42,680 when provided with assembly or machine language input. 8 00:00:43,160 --> 00:00:51,770 The concept of source code recovery is appealing in competitive software market, which drives ongoing 9 00:00:51,800 --> 00:00:55,910 research in developing effective decompilers. 10 00:00:56,300 --> 00:01:00,210 However, the compilation presents several challenges. 11 00:01:00,210 --> 00:01:09,900 These are the compilation process is losing when a program is compiled into machine language, variable 12 00:01:09,900 --> 00:01:16,710 and function names are lost and the type information must be inferred from data usage. 13 00:01:16,710 --> 00:01:23,760 For example, determining whether a sequence of 32 bit represents an integer, a floating point value 14 00:01:23,760 --> 00:01:27,510 or a pointer requires careful investigation. 15 00:01:30,340 --> 00:01:34,660 Compilation is a many to many operation. 16 00:01:34,690 --> 00:01:41,620 The translation of a source code program to assembly language can occur in multiple ways, and the reverse 17 00:01:41,620 --> 00:01:48,520 translation from machine language to source code can also have various valid representations. 18 00:01:48,910 --> 00:01:53,590 Consequently, compiling a file and immediately decompiling. 19 00:01:53,590 --> 00:01:59,680 It often results in a significantly different source files compared to the original. 20 00:02:02,940 --> 00:02:07,860 The compilers are language and library dependent. 21 00:02:08,160 --> 00:02:14,580 Different programming languages and libraries have distinct conventions and features. 22 00:02:14,610 --> 00:02:22,890 Processing a binary produced by a Delphi compiler with the compiler designed for generating C code can 23 00:02:22,890 --> 00:02:27,090 lead to unexpected and nonsensical results. 24 00:02:27,180 --> 00:02:35,190 Similarly, attempting to decompile a Windows binary with a knowledge of the Windows programming API 25 00:02:35,370 --> 00:02:38,670 may not produce useful output. 26 00:02:41,960 --> 00:02:50,420 Accurate assembly is crucial for precise Decompilation errors or omissions during the disassembly phase 27 00:02:50,450 --> 00:02:55,490 can propagate and affect the quality of the compiled code. 28 00:02:55,520 --> 00:03:03,440 Disassembled code can be verified against the processor reference manuals for correctness, but not 29 00:03:03,440 --> 00:03:10,280 definitive reference manuals exist to validate the output of the compiler. 30 00:03:10,430 --> 00:03:18,320 The process of disassembly and the compilation is not only useful for reverse engineering, but it also 31 00:03:18,320 --> 00:03:21,770 has implications for network security. 32 00:03:22,070 --> 00:03:28,970 Understanding the inner workings of software, including vulnerabilities and potential exploits, is 33 00:03:28,970 --> 00:03:33,810 crucial for ensuring the security of your computer software. 34 00:03:33,830 --> 00:03:41,090 By analyzing disassembled code, security professionals can identify potential weaknesses or malicious 35 00:03:41,090 --> 00:03:43,110 behavior in software. 36 00:03:43,350 --> 00:03:50,880 This knowledge helps in developing effective countermeasures such as intrusion detection systems, firewalls 37 00:03:50,880 --> 00:03:55,620 and antivirus software to protect networks from attacks. 38 00:03:55,710 --> 00:04:02,550 Furthermore, the compilation can assist in the identification and analysis of a malware. 39 00:04:02,790 --> 00:04:10,080 Reverse engineering malicious software provides insights into its functionality, communication methods 40 00:04:10,080 --> 00:04:14,040 and potential impact on the computer systems. 41 00:04:14,070 --> 00:04:20,820 This information enables security teams to develop effective strategies for detection, containment 42 00:04:20,820 --> 00:04:24,780 and removal of malware from compromised systems. 43 00:04:25,350 --> 00:04:33,570 Overall, disassembly and Decompilation play significant roles in both understanding software and enhancing 44 00:04:33,570 --> 00:04:34,740 network security. 45 00:04:34,770 --> 00:04:41,640 They empower security professionals to analyze and protect against potential threats, contributing 46 00:04:41,670 --> 00:04:44,190 to a safer digital environment.