Hybrid Cryptography System For Secure File Transfer Python — Complete Documentation & Simulation

Overview & System Context

Hybrid Cryptography System For Secure File Transfer Python: Comprehensive Web-Sourced Technical Investigation Exhaustive Research Dossier · Pure Web-Scraped Content: ~7905 Words · Real Software Screenshots: 3 1. Executive Overview & Technical Background Hyphanet (until mid-2023: Freenet) is a peer-to-peer platform for censorship-resistant, anonymous communication. It uses a decentralized distributed data store to keep and deliver information, and has a suite of free software for publishing and communicating on the Web without fear of censorship. Both Freenet and some of its associated tools were originally designed by Ian Clarke, who defined Freenet's goal as providing freedom of speech on the Internet with strong anonymity protection.

The distributed data store of Hyphanet is used by third-party programs and plugins to provide microblogging and media sharing, anonymous and decentralised version tracking, blogging, a generic web of trust for decentralized spam resistance, and Shoeshop for using Freenet over sneakernet. Hyphanet has been under continuous development since 2000. Freenet 0.7, released on 8 May 2008, is a major re-write incorporating a number of fundamental changes. The most fundamental change is support for darknet operation. Version 0.7 offered two modes of operation: a mode in which it connects only to friends, and an opennet-mode in which it connects to any other Freenet user. Both modes can be run simultaneously. When a user switches to pure darknet operation, Freenet becomes very difficult to detect from the outside. The transport layer created for the darknet mode allows communication over restricted routes as commonly found in mesh networks, as long as these connections follow a small-world structure. Other modifications include switching from TCP to UDP, which allows UDP hole punching along with faster transmission of messages between peers in the network. Freenet 0.7.5, released on 12 June 2009, offers a variety of improvements over 0.7.

These include reduced memory usage, faster insert and retrieval of content, significant improvements to the FProxy web interface used for browsing freesites, and a large number of smaller bugfixes, performance enhancements, and usability improvements. Version 0.7.5 also shipped with a new version of the Windows installer. As of build 1226, released on 30 July 2009, features that were written include significant security improvements against both attackers acting on the network and physical seizure of the computer running the node. As of build 1468, released on 11 July 2015, the Freenet core stopped using the db4o database and laid the foundation for an efficient interface to the Web of Trust plugin which provides spam resistance. Freenet has always been free software, but until 2011 it required users to install Java. This problem was solved by making Freenet compatible with OpenJDK, a free and open source implementation of the Java Platform. On 11 February 2015, Freenet received the SUMA-Award for "protection against total surveillance".

The Hyphanet file sharing network stores documents and allows them to be retrieved later by an associated key, as is now possible with protocols such as HTTP. The network is designed to be highly survivable. The system has no central servers and is not subject to the control of any one individual or organization, including the designers of Freenet. The codebase size is over 192,000 lines of code. Information stored on Hyphanet is distributed around the network and stored on several different nodes. Encryption of data and relaying of requests makes it difficult to determine who inserted content into Hyphanet, who requested that content, or where the content was stored. This protects the anonymity of participants, and also makes it very difficult to censor specific content. Content is stored encrypted, making it difficult for even the operator of a node to determine what is stored on that node. This provides plausible deniability; which, in combination with request relaying, means that safe harbor laws that protect service providers may also protect Hyphanet node operators. When asked about the topic, Freenet developers defer to the EFF discussion which says that not being able to filter anything is a safe choice.

A user wishing to share a file or update a freesite "inserts" the file "to the network" After "insertion" is finished, the publishing node is free to shut down, because the file is stored in the network. It will remain available for other users whether or not the original publishing node is online. No single node is responsible for the content; instead, it is replicated to many different nodes. Two advantages of this design are high reliability and anonymity. Information remains available even if the publisher node goes offline, and is anonymously spread over many hosting nodes as encrypted blocks, not entire files. The key disadvantage of the storage method is that no one node is responsible for any chunk of data. If a piece of data is not retrieved for some time and a node keeps getting new data, it will drop the old data sometime when its allocated disk space is fully used. In this way Hyphanet tends to 'forget' data which is not retrieved regularly (see also Effect). While users can insert data into the network, there is no way to delete data. Due to Freenet's anonymous nature the original publishing node or owner of any piece of data is unknown. The only way data can be removed is if users don't request it.

Figure 1: SECURE FILE STORAGE ON CLOUD USING HYBRID CRYPTOGRAPHY - PYTHON - YouTube The Hyphanet protocol uses a key-based routing protocol, similar to distributed hash tables. The routing algorithm changed significantly in version 0.7. Prior to version 0.7, Freenet used a heuristic routing algorithm where each node had no fixed location, and routing was based on which node had served a key closest to the key being fetched (in version 0.3) or which is estimated to serve it faster (in version 0.5). In either case, new connections were sometimes added to downstream nodes (i.e.

the node that answered the request) when requests succeeded, and old nodes were discarded in least recently used order (or something close to it). Oskar Sandberg's research (during the development of version 0.7) shows that this "path folding" is critical, and that a very simple routing algorithm will suffice provided there is path folding. The disadvantage of this is that it is very easy for an attacker to find Hyphanet nodes, and connect to them, because every node is continually attempting to find new connections. In version 0.7, Hyphanet starts supporting both "opennet" (similar to the old algorithms, but simpler), and "darknet" (all node connections are set up manually, so only your friends know your node's IP address). Darknet is less convenient, but much more secure against a distant attacker. This change required major changes in the routing algorithm.

Every node has a location, which is a number between 0 and 1. When a key is requested, first the node checks the local data store. If it's not found, the key's hash is turned into another number in the same range, and the request is routed to the node whose location is closest to the key. This goes on until some number of hops is exceeded, there are no more nodes to search, or the data is found. If the data is found, it is cached on each node along the path. So there is no one source node for a key, and attempting to find where it is currently stored will result in it being cached more widely. Essentially the same process is used to insert a document into the network: the data is routed according to the key until it runs out of hops, and if no existing document is found with the same key, it is stored on each node. If older data is found, the older data is propagated and returned to the originator, and the insert "collides". But this works only if the locations are clustered in the right way. Hyphanet assumes that the darknet (a subset of the global social network) is a small-world network, and nodes constantly attempt to swap locations (using the Metropolis–Hastings algorithm) in order to minimize their distance to their neighbors. If the network actually is a small-world network, Freenet should find data reasonably quickly; ideally on the order of O ( [ log I ( n ) ] 2 ) {\displaystyle O{\big (}[\log(n)]^{2}{\big )}} hops in big O notation. However, it does not guarantee that data will be found at all.

Eventually, either the document is found or the hop limit is exceeded. The terminal node sends a reply that makes its way back to the originator along the route specified by the intermediate nodes' records of pending requests. The intermediate nodes may choose to cache the document along the way. Besides saving bandwidth, this also makes documents harder to censor as there is no one "source node".

Initially, the locations in darknet are distributed randomly. This means that routing of requests is essentially random. In opennet connections are established by a join request which provides an optimized network structure if the existing network is already optimized. So the data in a newly started Hyphanet will be distributed somewhat randomly. As location swapping (on darknet) and path folding (on opennet) progress, nodes which are close to one another will increasingly have close locations, and nodes which are far away will have distant locations. Data with similar keys will be stored on the same node. The result is that the network will self-organize into a distributed, clustered structure where nodes tend to hold data items that are close together in key space. There will probably be multiple such clusters throughout the network, any given document being replicated numerous times, depending on how much it is used. This is a kind of "spontaneous symmetry breaking", in which an initially symmetric state (all nodes being the same, with random initial keys for each other) leads to a highly asymmetric situation, with nodes coming to specialize in data that has closely related keys. There are forces which tend to cause clustering (shared closeness data spreads throughout the network), and forces that tend to break up clusters (local caching of commonly used data). These forces will be different depending on how often data is used, so that seldom-used data will tend to be on just a few nodes which specialize in providing that data, and frequently used items will be spread widely throughout the network. This automatic mirroring counteracts the times when web traffic becomes overloaded, and due to a mature network's intelligent routing, a network of size n should require only log(n) time to retrieve a document on average.

Unlike many other P2P applications Freenet does not provide comprehensive functionality itself. Freenet is modular and features an API called Freenet Client Protocol (FCP) for other programs to use to implement services such as message boards, file sharing, or online chat. FMS was designed to address problems with Frost such as denial of service attacks and spam. Users publish trust lists, and each user downloads messages only from identities they trust and identities trusted by identities they trust. FMS is developed anonymously and can be downloaded from the FMS freesite within Freenet. It does not have an official site on the normal Internet. It features random post delay, support for many identities, and a distinction between trusting a user's posts and trusting their trust list. It is written in C++ and is a separate application from Freenet which uses the Freenet Client Protocol (FCP) to interface with Freenet. Frost Figure 2: GitHub - JimChr-R4GN4R/FilesCrypterSavior: This is a GUI program based ...

Frost includes support for convenient file sharing, but its design is inherently vulnerable to spam and denial of service attacks. Frost can be downloaded from the Frost home page on SourceForge, or from the Frost freesite within Freenet. It is not endorsed by the Freenet developers. Frost is written in Java and is a separate application from Freenet. Sone Sone provides a simpler interface inspired by Facebook with public anonymous discussions and image galleries. It provides an API for control from other programs is also used to implement a comment system for static websites in the regular internet.

jSite is a tool to upload websites. It handles keys and manages uploading files. Infocalypse Infocalypse is an extension for the distributed revision control system Mercurial. It uses an optimized structure to minimize the number of requests to retrieve new data, and allows supporting a repository by securely reuploading most parts of the data without requiring the owner's private keys.

Figure 3: GitHub - Paras0681/Secure-File-sharing-using-Hybrid-Cryptography-and ... 2. System Architecture & Core Working Principles FCPLib (Freenet Client Protocol Library) aims to be a cross-platform natively compiled set of C++-based functions for storing and retrieving information to and from Freenet. FCPLib supports Windows NT/2K/XP, Debian, BSD, Solaris, and macOS.

lib-pyFreenet Using Freenet 0.7.5, several attacks have been identified via the analysis of Freenet code, routing and request processing that seriously damage the anonymity of Freenet and similar systems. While the attack doesn't work in special cases, it works in most ordinary cases. This type of attack is serious because it can be used to discover other attacks. As nodes become better connected, the number of victim nodes that can be attacked with the RTI attack increases.

Peer-to-peer web hosting Rendezvous protocol Anonymous P2P Crypto-anarchism Cypherpunk Distributed file system Freedom of information Friend-to-friend Unified Extensible Firmware Interface or UEFI is a specification for the firmware architecture of a computing platform. When a computer is powered on, the UEFI implementation typically runs first, before the operating system or any other program is loaded. Examples include AMI Aptio, Phoenix SecureCore, TianoCore EDK II, and InsydeH2O. UEFI replaces the BIOS that was present in the boot ROM of all personal computers that are IBM PC compatible, although it can provide backwards compatibility with the BIOS using CSM booting. Unlike the BIOS, which was originally developed by IBM as a proprietary architecture, the UEFI specification is managed by an industry consortium. Most production firmware implementations for both remain proprietary. Intel developed the original Extensible Firmware Interface (EFI) specification. The last Intel version of EFI was 1.10 released in 2005. Subsequent versions have been developed as UEFI by the UEFI Forum. UEFI is independent of platform and programming language, but C is used for the reference implementation TianoCore EDKII.

x86 (IA-32, x86-64) Itanium (IA-64) ARM (AArch32, AArch64) RISC-V (32-bit, 64-bit, 128-bit) LoongArch (32-bit, 64-bit) Unofficial UEFI support is under development for POWERPC64 by implementing TianoCore EDK II on top of OPAL, the OpenPOWER abstraction layer, running in little-endian mode. For MIPS, there also exists an unofficial project, based on the original EDK. However, both projects have since been abandoned as of November 2016 and September 2015 respectively.

UEFI only allows executing UEFI applications that match the firmware's bit-width, even if the processor supports smaller or larger bit-widths. For example, a 64-bit UEFI firmware may only execute 64-bit UEFI applications, even if the processor has a 32-bit processor mode. Some low-end computers have been shipped with 32-bit UEFI firmware running on 64-bit CPUs. Once a UEFI application ends the boot services, and gets granted full control over the system, it becomes possible to change the processor execution mode. However, calling runtime services requires shortly changing back to the original processor mode, as runtime services may only be called from the same processor mode as the firmware implementation. The Linux kernel added support for booting 64-bit kernels on 32-bit UEFI firmware implementations with x86-64 CPUs since version 3.15, requiring the UEFI boot loader to support the EFI handover protocol. The EFI handover protocol allows UEFI boot loaders to defer the UEFI initialization to the kernel's EFI boot stub, so that only the kernel does the UEFI initialization.

In addition to the standard PC disk partition scheme that uses a master boot record (MBR), UEFI also works with the GUID Partition Table (GPT) partitioning scheme, which is free from many of the limitations of MBR. In particular, the MBR limits on the number and size of disk partitions (up to four primary partitions per disk, and up to 2 TB (2 × 240 bytes) per disk) are relaxed. More specifically, GPT allows for a maximum disk and partition size of 8 ZiB (8 × 270 bytes) with 512 byte sectors.

The UEFI specification only supports FAT12/16/32 partitions that are on GPT or MBR disks as well as El Torito-formatted optical discs. Although GPT is a part of the UEFI standard, it may also be usable by BIOS PCs to boot an operating system off of. Support for GPT in Linux is enabled by turning on the option CONFIG_EFI_PARTITION (EFI GUID Partition Support) during kernel configuration. This option allows Linux to recognize and use GPT disks after the system firmware passes control over the system to Linux. For reverse compatibility, Linux can use GPT disks in BIOS-based systems for both data storage and booting, as both GRUB 2 and Linux are GPT-aware. Such a setup is usually referred to as BIOS-GPT. As GPT incorporates the protective MBR, a BIOS-based computer can boot from a GPT disk using a GPT-aware boot loader stored in the protective MBR's bootstrap code area. In the case of GRUB, such a configuration requires a BIOS boot partition for GRUB to embed its second-stage code due to absence of the post-MBR gap in GPT partitioned disks (which is taken over by the GPT's Primary Header and Primary Partition Table). Commonly 1 MB in size, this partition's Globally Unique Identifier (GUID) in GPT scheme is 21686148-6449-6E6F-744E-656564454649 and is used by GRUB only in BIOS-GPT setups. From GRUB's perspective, no such partition type exists in case of MBR partitioning. This partition is not required if the system is UEFI-based because no embedding of the second-stage code is needed in that case. UEFI systems can access GPT disks and boot directly from them, which allows Linux to use UEFI boot methods. Booting Linux from GPT disks on UEFI systems involves creation of an EFI system partition (ESP), which contains UEFI applications such as bootloaders, operating system kernels, and utility software. Such a setup is usually referred to as UEFI-GPT, while ESP is recommended to be at least 512 MB in size and formatted with a FAT32 filesystem for maximum compatibility. For backward compatibility, some UEFI implementations also support booting from MBR-partitioned disks through the Compatibility Support Module (CSM) that provides legacy BIOS compatibility. In that case, booting Linux on UEFI systems is the same as on legacy BIOS-based systems.

Graphics Output Protocol (GOP) services The Graphics Output Protocol (GOP) provides runtime services; see also Graphics features section below. The operating system is permitted to directly write to the framebuffer and BLT provided by GOP during runtime mode. UEFI memory map services This boot service allows the bootloader to obtain information on how the memory is laid out. SMM services The SMM ("ring -2") is an x86 mode that provides secure code execution isolated from all lower rings. Modern UEFI generalizes the concept to Management Mode (MM) to also encompass alternative technologoies such as TrustZone. One common use of the MM/SMM services is as a secure store of variables. ACPI services SMBIOS services Devicetree services (for RISC processors) These runtime services allow the operating system to obtain information about the installed hardware and how to make use of them. Variable services UEFI variables store non-volatile data. The variable storage is conceptually divided into namespaces identified by GUIDs. Each namespace can contain any number of variable entries, which are key/value pairs (Unicode string key, variable-length byte-array value). Each entry also carries an attributes bitfield, which can restrict its access to only boot or run-time (among other, more advanced, uses). Some UEFI variables are shared between platform firmware and operating systems. For example, the OS may set the BootOrder and Boot#### variables under the EFI_GLOBAL_VARIABLE namespace to influence the UEFI boot manager's future choices. Other variables may be private to one side. For example, UEFI variables can be used by an OS to keep crash messages in NVRAM after a crash for the operating system to retrieve after a reboot. Time services UEFI provides time services. Time services include support for time zone and daylight saving fields, which allow the hardware real-time clock to be set to local time or UTC. On machines using a PC-AT real-time clock, Microsoft Windows does not use the EFI time zone and DST fields, and expects the hardware clock to provide local time like traditional BIOS-based Windows did. As a result the HW clock cannot be set to UTC unless using recent versions and an entry in the Windows registry is set to indicate the use of UTC.

UEFI executes independent programs known as UEFI applications, which are stored as files on the EFI system partition. These can be launched by the firmware boot manager or other UEFI applications. They may be developed independently of the original equipment manufacturer (OEM). A type of UEFI application is an OS boot loader such as GRUB, rEFInd, systemd-boot, and Windows Boot Manager, which loads some OS files into memory and executes them. The UEFI Shell is an example of a UEFI application that launches other UEFI applications. Some OS loaders do the same, providing a user interface to allow the selection of another UEFI application to run.

An EFI system partition, often abbreviated to ESP, is a data storage device partition that is used in computers adhering to the UEFI specification. Accessed by the UEFI firmware when a computer is powered up, it stores UEFI applications and the files these applications need to run, including operating system boot loaders. Supported partition table schemes include MBR and GPT, as well as El Torito volumes on optical discs. For use on ESPs, UEFI defines a specific version of the FAT file system, which is maintained as part of the UEFI specification and independently from the original FAT specification, encompassing the FAT32, FAT16 and FAT12 file systems. The ESP retains the BIOS-style boot sector from FAT, though this is not used by UEFI.

Booting UEFI systems from GPT-partitioned disks is commonly called UEFI-GPT booting. The alternative is to boot from an EFI System Partition on MBR-partitioned disks, commonly called UEFI-MBR. UEFI-MBR capability is required by the UEFI specification, but some UEFI firmware implementations immediately switch to BIOS-based CSM booting depending on the type of the boot disk's partition table, effectively preventing it from occurring. It is also common for a boot manager to have a textual user interface to allow the user to select the desired OS (or setup utility) from a list of available boot options. On PC platforms, firmware supporting UEFI boot is often referred to as a "UEFI BIOS", though some newer x86 platforms exclude CSM support entirely.

The UEFI specification defines a Secure Boot that can secure the boot process by preventing the loading of UEFI drivers or OS boot loaders that are not signed with an acceptable digital signature. When Secure Boot is enabled, it is initially placed in "setup" mode, which allows a public key known as the "platform key" (PK) to be written to the firmware. Once the key is written, Secure Boot enters "User" mode, where only UEFI drivers and OS boot loaders signed with the platform key can be loaded by the firmware. Additional "key exchange keys" (KEK) can be added to a database stored in memory to allow other certificates to be used, but they must still have a connection to the private portion of the platform key. Secure Boot can also be placed in "Custom" mode, where additional public keys can be added to the system that do not match the private key. Secure Boot is supported by Windows 8 and 8.1, Windows Server 2012 and 2012 R2, Windows 10, Windows Server 2016, 2019, and 2022, and Windows 11, VMware vSphere 6.5 and several Linux distributions including Fedora (since version 18), openSUSE (since version 12.3), RHEL (since version 7), CentOS (since version 7), Debian (since version 10), Ubuntu (since version 12.04.2), Linux Mint (since version 21.3), and AlmaLinux OS (since version 8.4). As of January 2025, FreeBSD support is in its planning stage.

3. Software Implementation, Frameworks & Protocols The UEFI standards include a specification for a shell environment. The shell is a UEFI application that can be used to execute other UEFI applications, including UEFI boot loaders. It also includes built-in commands for obtaining various other information about the system or the firmware, including getting the memory map (memmap), modifying boot manager variables (bcfg), running partitioning programs (diskpart), loading UEFI drivers, and editing text files (edit). It implements a scripting language with support for if-statements, for-loops, and environment variables. The UEFI shell is not a mandatory component of the firmware. It tends to be pre-loaded into server motherboards, which allows it to be launched by appropriate key press combinations. Some other motherboards provide a direct option in firmware setup for launching, e.g. compiled x86-64 version of the shell needs to be made available as /SHELLX64.EFI. For other systems, the solution is either creating an appropriate USB flash drive (as BOOTxxxx.efi, making use of boot loader auto-detection) or adding manually (bcfg) a boot option associated with the compiled version of shell. Source code for a UEFI shell can be downloaded from the Intel's TianoCore UDK/EDK2 project. A pre-built ShellBinPkg is also available. Shell v2 works best in UEFI 2.3+ systems and is recommended over Shell v1 in those systems. Shell v1 should work in all UEFI systems.

The shell v2 includes a much broader set of features in its default build. For example, there is a new devtree for showing a tree of devices. Class 0: Legacy BIOS Class 1: UEFI with a CSM interface and no external UEFI interface. The only UEFI interfaces are internal to the firmware. Class 2: UEFI with CSM and external UEFI interfaces, e.g. UEFI Boot. Class 3: UEFI without a CSM interface and with an external UEFI interface. Class 3+: UEFI class 3 that has Secure Boot enabled. Starting from the 10th Gen Intel Core, Intel no longer provides Legacy Video BIOS for the iGPU (Intel Graphics Technology). Legacy boot with those CPUs requires a Legacy Video BIOS, which can still be provided by a video card.

Successful dispatching of PEIMs (pre-EFI initialization modules). Initializing permanent memory (RAM). Handing over to the next stage, DXE. Facilitating the communication of PEIMs called PPI. Intel's implementation of EFI is the Intel Platform Innovation Framework, codenamed Tiano. Tiano runs on Intel's XScale, Itanium, IA-32 and x86-64 processors, and is proprietary software, although a portion of the code has been released under the BSD license or Eclipse Public License (EPL) as TianoCore EDK II. TianoCore can be used as a payload for coreboot. Phoenix Technologies' implementation of UEFI is branded as SecureCore Technology (SCT). American Megatrends offers its own UEFI firmware implementation known as Aptio, while Insyde Software offers InsydeH2O, and Byosoft offers ByoCore. In December 2018, Microsoft released an open source version of its TianoCore EDK2-based UEFI implementation from the Surface line, Project Mu. An implementation of the UEFI API was introduced into the Universal Boot Loader (Das U-Boot) in 2017. On the ARMv8 architecture Linux distributions use the U-Boot UEFI implementation in conjunction with GNU GRUB for booting (e.g. SUSE Linux), the same holds true for OpenBSD. For booting from iSCSI iPXE can be used as a UEFI application loaded by U-Boot.

Intel's first Itanium workstations and servers, released in 2000, implemented EFI 1.02. Hewlett-Packard's first Itanium 2 systems, released in 2002, implemented EFI 1.10. These systems were able to boot Windows, Linux, FreeBSD and HP-UX. OpenVMS added UEFI capability in June 2003. In January 2006, Apple Inc. shipped its first Intel-based Macintosh computers. These systems used EFI instead of Open Firmware, which had been used on its previous PowerPC-based systems. On 5 April 2006, Apple first released Boot Camp, which produces a Windows drivers disk and a non-destructive partitioning tool to allow the installation of Windows XP or Vista without requiring a reinstallation of Mac OS X (now macOS). A firmware update was also released that added BIOS compatibility to its EFI implementation. Subsequent Macintosh models shipped with the newer firmware. During 2005, more than one million Intel systems shipped with Intel's implementation of UEFI. New mobile, desktop and server products, using Intel's implementation of UEFI, started shipping in 2006. For instance, boards that use the Intel 945 chipset series use Intel's UEFI firmware implementation. Since 2005, EFI has also been implemented on non-PC architectures, such as embedded systems based on XScale cores. The EDK (EFI Developer Kit) includes an NT32 target, which allows EFI firmware and EFI applications to run within a Windows application. However, no direct hardware access is allowed by EDK NT32. This means only a subset of EFI application and drivers can be executed by the EDK NT32 target. In 2008, more x86-64 systems adopted UEFI. While many of these systems still allow booting only the BIOS-based OSes via the Compatibility Support Module (CSM) (thus not appearing to the user to be UEFI-based), other systems started to allow booting UEFI-based OSes. For example, IBM x3450 server, MSI motherboards with ClickBIOS and HP EliteBook Notebook PCs. In 2009, IBM shipped System x machines (x3550 M2, x3650 M2, iDataPlex dx360 M2) and BladeCenter HS22 with UEFI capability. Dell shipped PowerEdge T610, R610, R710, M610 and M710 servers with UEFI capability. More commercially available systems are mentioned in a UEFI whitepaper. In 2011, major vendors (such as ASRock, Asus, Gigabyte, and MSI) launched several consumer-oriented motherboards using the Intel 6-series LGA 1155 chipset and AMD 9 Series AM3+ chipsets with UEFI. With the release of Windows 8 in October 2012, Microsoft's certification requirements now require that computers include firmware that implements the UEFI specification. Furthermore, if the computer supports the "Connected Standby" feature of Windows 8 (which allows devices to have power management comparable to smartphones, with an almost instantaneous return from standby mode), then the firmware is not permitted to contain a Compatibility Support Module (CSM). As such, systems that support Connected Standby are incapable of booting Legacy BIOS operating systems. In October 2017, Intel announced that it would remove legacy PC BIOS support from all its products by 2020, in favor of UEFI Class 3. By 2019, all computers based on Intel platforms no longer have legacy PC BIOS support.

The Linux kernel has been able to use EFI at boot time since the early 2000s, using the elilo EFI boot loader and more recently, EFI versions of GRUB or systemd-boot. Grub+Linux also supports booting from a GUID partition table without UEFI. The distribution Ubuntu added support for UEFI Secure Boot as of version 12.10. The Linux kernel can be compiled with the option to run as an EFI bootloader on its own through the EFI boot stub feature. In the Linux kernel, either the ACPI protocol (usually used on PC-compatible machines) or the DeviceTree protocol (usually used on smartphones and tablet computers) can be used with UEFI. HP-UX has used (U)EFI as its boot mechanism on IA-64 systems since 2002. OpenVMS has used EFI on IA-64 since its initial evaluation release in December 2003, and for production releases since January 2005. OpenVMS on x86-64 also uses UEFI to boot the operating system. Apple uses EFI for its line of Intel-based Macs. Mac OS X v10.4 Tiger and Mac OS X v10.5 Leopard implements EFI v1.10 in 32-bit mode even on 64-bit CPUs, but full support arrived with OS X v10.8 Mountain Lion. Windows XP 64-bit Edition and Windows Server 2003 for IA-64, all of which are for the Intel Itanium family of processors, implement EFI, a requirement of the platform through the DIG64 specification. The pre-release versions of Windows Server 2003 for 64-bit Itanium systems (Windows Advanced Server Limited Edition and Windows Datacenter Server Limited Edition, which were labeled as 64-bit versions of Windows 2000 for the time being) implemented EFI 1.10 in 2002. Microsoft introduced UEFI for x86-64 Windows operating systems beginning with Windows Vista SP1 and Windows Server 2008, however only UGA (Universal Graphic Adapter) 1.1 or Legacy BIOS INT 10h is supported; Graphics Output Protocol (GOP) is not supported. Therefore, PCs running 64-bit versions of Windows Vista SP1 and SP2, Windows 7, Windows Server 2008 and Windows Server 2008 R2 are compatible with UEFI Class 2. 32-bit UEFI was originally not supported since vendors did not have any interest in producing native 32-bit UEFI firmware because of the mainstream status of 64-bit computing. Windows 8 finally introduced further optimizations for UEFI systems, including Graphics Output Protocol (GOP) support, a faster startup, 32-bit UEFI support, and Secure Boot support. Since Windows 8, the UEFI firmware with ACPI protocol is a mandatory requirement for ARM-based Microsoft Windows operating systems. Microsoft began requiring UEFI to run Windows starting with Windows 11, with the exception of IoT Enterprise editions of Windows 11 since version 24H2. On 5 March 2013, the FreeBSD Foundation awarded a grant to a developer seeking to add UEFI support to the FreeBSD kernel and bootloader. The changes were initially stored in a discrete branch of the FreeBSD source code, but were merged into the mainline source on 4 April 2014 (revision 264095); the changes include support in the installer as well. UEFI boot support for amd64 first appeared in FreeBSD 10.1 and for arm64 in FreeBSD 11.0. NetBSD supports UEFI since version 8.0 for i386 and amd64 architectures as well as on various ARM platforms since version 9.0. Oracle Solaris 11.1 and later support UEFI boot for x86 systems with UEFI firmware version 2.1 or later. GRUB 2 is used as the boot loader on x86.

OpenBSD 5.9 introduced UEFI boot support for 64-bit x86 systems using its own custom loader, OpenBSD 6.0 extended that support to include ARMv7. illumos added basic UEFI support in October 2017. ArcaOS supports UEFI booting since the 5.1 release. ArcaOS' UEFI support emulates specific BIOS functionality which the operating system depends on (particularly interrupts INT 10H and INT 13H).

In 2011, Microsoft announced that computers certified to run its Windows 8 operating system had to ship with Microsoft's public key enrolled and Secure Boot enabled, which implies that using UEFI is a requirement for these devices. Following the announcement, critics and free-software/open-source advocates, including the Free Software Foundation, expressed concern that Microsoft might use the Secure Boot functionality of UEFI to restrict the installation of alternative operating systems such as Linux. Microsoft denied that the Secure Boot requirement was intended to serve as a form of lock-in and clarified its requirements by stating that x86-based systems certified for Windows 8 must allow Secure Boot to enter custom mode or be disabled, but not on systems using the ARM architecture. Windows 10 allows OEMs to decide whether or not Secure Boot can be managed by users of their x86 systems. Other developers raised concerns about the legal and practical issues of implementing support for Secure Boot on Linux systems in general. Former Red Hat developer Matthew Garrett noted that conditions in the GNU General Public License version 3 may prevent the use of the GNU GRand Unified Bootloader without a distribution's developer disclosing the private key (however, the Free Software Foundation has since clarified its position, assuring that the responsibility to make keys available was held by the hardware manufacturer), and that it would also be difficult for advanced users to build custom kernels that could function with Secure Boot enabled without self-signing them.

Other developers suggested that signed builds of Linux with another key could be provided, but noted that it would be difficult to persuade OEMs to ship their computers with the required key alongside the Microsoft key. Several major Linux distributions have developed different implementations for Secure Boot. Garrett himself developed a minimal bootloader known as a shim, which is a precompiled, signed bootloader that allows the user to individually trust keys provided by Linux distributions. Ubuntu 12.10 uses an older version of shim pre-configured for use with Canonical's own key that verifies only the bootloader and allows unsigned kernels to be loaded; developers believed that the practice of signing only the bootloader is more feasible, since a trusted kernel is effective at securing only the user space, and not the pre-boot state for which Secure Boot is designed to add protection. That also allows users to build their own kernels and use custom kernel modules as well, without the need to reconfigure the system. Canonical also maintains its own private key to sign installations of Ubuntu pre-loaded on certified OEM computers that run the operating system, and also plans to enforce a Secure Boot requirement as well—requiring both a Canonical key and a Microsoft key (for compatibility reasons) to be included in their firmware. Fedora also uses shim, but requires that both the kernel and its modules be signed as well. shim has Machine Owner Key (MOK) that can be used to sign locally compiled kernels and other software not signed by distribution maintainer, without changing the Secure Boot mode to setup mode. It has been disputed whether the operating-system kernel and its modules must be signed as well; while the UEFI specifications do not require it, Microsoft has asserted that their contractual requirements do, and that it reserves the right to revoke any certificates used to sign code that can be used to compromise the security of the system. In Windows, if Secure Boot is enabled, all kernel drivers must be digitally signed; non-WHQL drivers may be refused to load. In February 2013, another Red Hat developer attempted to submit a patch to the Linux kernel that would allow it to parse Microsoft's authenticode signing using a master X.509 key embedded in PE files signed by Microsoft. However, the proposal was criticized by Linux creator Linus Torvalds, who argued that Red Hat was accommodating Microsoft's control over the Secure Boot infrastructure. On 26 March 2013, the Spanish free-software development group Hispalinux filed a formal complaint with the European Commission, contending that Microsoft's Secure Boot requirements on OEM systems were "obstructive" and anti-competitive. At the Black Hat conference in August 2013, a group of security researchers presented a series of exploits in specific vendor implementations of UEFI that could be used to exploit Secure Boot. In August 2016 it was reported that two security researchers had found the "golden key" security key Microsoft uses in signing operating systems. Technically, no key was exposed, but an exploitable binary signed by the key was. This allows software to execute as though it were signed by Microsoft, presenting potential risks for rootkit and bootkit attacks. This also complicates remediation efforts, since a patch can potentially be downgraded by replacing it with the signed exploitable binary. Microsoft stated that the vulnerability only affects ARM architecture and Windows RT devices and released two updates; however, reports noted that these updates do not completely prevent exploitation because fully resolving the vulnerability would require key replacements in end-user firmware. On 1 March 2023, researchers from ESET reported discovering "BlackLotus", described as the first active UEFI bootkit capable of bypassing UEFI Secure Boot by exploiting the limitations of the previous security updates.

In August 2024, the Windows 11 and Windows 10 security updates applied the Secure Boot Advanced Targeting (SBAT) settings to device's UEFI NVRAM, which caused some Linux distributions to fail to load. SBAT is a protocol that supported in new versions of Windows Boot Manager and shim, which refuse buggy or vulnerable intermediate bootloaders (usually older versions of Windows Boot Manager and GRUB) to load in the boot process. The change was reverted the next month. In June 2025, LWN.net reported that the Microsoft UEFI CA 2011 certificate will be expired on June 24, 2026, which may refuse some Linux to load if Secure Boot is enabled. However, in TianoCore EDK II as well as many commercial UEFI implementations (such as AMI Aptio), time/date check for Secure Boot certificate is usually disabled by default. Many Linux distributions support UEFI Secure Boot as of January 2025, such as RHEL (RHEL 7 and later), CentOS (CentOS 7 and later), Ubuntu, Fedora, Debian (Debian 10 and later), OpenSUSE, and SUSE Linux Enterprise.

Official website UEFI Specifications Intel-sponsored open-source EFI Framework initiative Intel EFI/UEFI portal Microsoft UEFI Support and Requirements for Windows Operating Systems How Windows 8 Hybrid Shutdown / Fast Boot feature works Securing the Windows 10 Boot Process LoJax: First UEFI rootkit found in the wild, courtesy of the Sednit group Python Interpreter for UEFI Shell A python package for hybrid file encryption and decryption. securefile is for n-layer file encryption. This package provides a basic two-way encryption algorithm for a file. It supports approximately all kind of file encoding. The package provides RSA, DES, AES and Shift Cipher and base64 algorithm for file encoding and decoding.

4. Practical Deployment, Analysis & Case Studies The Data Encryption Standard (DES) is a symmetric-key block cipher published by the National Institute of Standards and Technology (NIST). DES is an implementation of a Feistel Cipher. It uses 16 round Feistel structure. The block size is 64-bit. Though, key length is 64-bit, DES has an effective key length of 56 bits, since 8 of the 64 bits of the key are not used by the encryption algorithm.

RSA algorithm is a public key encryption technique and is considered as the most secure way of encryption. RSA algorithm is asymmetric cryptography algorithm. Asymmetric actually means that it works on two different keys i.e. Public Key and Private Key. As the name describes that the Public Key is given to everyone and Private key is kept private. The more popular and widely adopted symmetric encrypt algorithm likely to be encountered nowadays is the Advanced Encryption Standard (AES). It is found at least six time faster than triple DES. A replacement for DES was needed as its key size was too small. With increasing computing power, it was considered vulnerable against exhaustive key search attack.

Triple DES was designed to overcome this drawback but it was found slow. Base64 encoding schemes are commonly used when there is a need to encode binary data that needs be stored and transferred over media that are designed to deal with textual data. This is to ensure that the data remains intact without modification during transport.

“A Survey on Performance Analysis of DES , AES and RSA Algorithm along with LSB Substitution Technique.”, 2013. P. V. Maitri and A. Verma, “Secure file storage in cloud computing using hybrid cryptography algorithm,” 2016 International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET), Secure Safe is a web-based application designed for secure file storage and transfer. It employs advanced cryptographic techniques to ensure the confidentiality and integrity of user data. By utilizing a hybrid encryption approach, Secure Safe allows users to upload, store, and download files securely.

Contributions are welcome! If you would like to contribute to Secure Safe, please follow these steps: While symmetric encryption is fast, it is less secure as it uses a single key for encryption and decryption. On the other hand, asymmetric encryption is much safer as two mathematically connected keys are used, but it is slower in terms of speed. To get the best of both worlds, we can use hybrid encryption.

In hybrid encryption , a new symmetric key is generated each time we send data, and it is encrypted with the recipient's public key. The encrypted data and the symmetric key are then sent together. When the recipient receives the data, they decrypt the symmetric key with their private key and then use it to decrypt the data. 5. Performance Evaluation & Extended Technical Observations In practice, to send data over an insecure network without SSL, we need to install necessary packages: Then generate a public-private key pair, share the private key with the receiver, generate a symmetric key, encrypt the data with the symmetric key, encrypt the symmetric key with the public key, encode both with base64, send the data along with the encrypted symmetric key, receive, decode the data and the symmetric key from base64, decrypt the symmetric key with the private key, and finally decrypt the data with the symmetric key.

For this scenario, we utilized RSA keys of 2048 bits. However, depending on your specific use case, you can select from key sizes of 1024, 2048, or 4096 bits. The private key can be stored on the client side as either a .PEM file or as a configuration variable. A python package for hybrid file encryption and decryption. securefile is for n-layer file encryption. This package provides a basic two-way encryption algorithm for a file. It supports approximately all kind of file encoding. The package provides RSA, DES, AES and Shift Cipher and base64 algorithm for file encoding and decoding.

The Data Encryption Standard (DES) is a symmetric-key block cipher published by the National Institute of Standards and Technology (NIST). DES is an implementation of a Feistel Cipher. It uses 16 round Feistel structure. The block size is 64-bit. Though, key length is 64-bit, DES has an effective key length of 56 bits, since 8 of the 64 bits of the key are not used by the encryption algorithm.

RSA algorithm is a public key encryption technique and is considered as the most secure way of encryption. RSA algorithm is asymmetric cryptography algorithm. Asymmetric actually means that it works on two different keys i.e. Public Key and Private Key. As the name describes that the Public Key is given to everyone and Private key is kept private. The more popular and widely adopted symmetric encrypt algorithm likely to be encountered nowadays is the Advanced Encryption Standard (AES). It is found at least six time faster than triple DES. A replacement for DES was needed as its key size was too small. With increasing computing power, it was considered vulnerable against exhaustive key search attack.

Triple DES was designed to overcome this drawback but it was found slow. Base64 encoding schemes are commonly used when there is a need to encode binary data that needs be stored and transferred over media that are designed to deal with textual data. This is to ensure that the data remains intact without modification during transport.

A python package for hybrid file encryption and decryption. securefile is for n-layer file encryption. This package provides a basic two-way encryption algorithm for a file. It supports approximately all kind of file encoding. The package provides RSA, DES, AES and Shift Cipher and base64 algorithm for file encoding and decoding. A Python implementation of hybrid file encryption using Kyber-like post-quantum cryptography and RSA. This project demonstrates secure file encryption and decryption for multiple users by combining the efficiency of symmetric key encryption (mock Kyber) with the robust key exchange capabilities of RSA.

Output After running the script, the original file content is securely encrypted and can only be decrypted by authorized users. This repository is ideal for educational purposes or as a foundation for integrating hybrid cryptographic solutions in secure file sharing applications. A Python implementation of hybrid file encryption using Kyber-like post-quantum cryptography and RSA. This project demonstrates secure file encryption and decryption for multiple users by combining the efficiency of symmetric key encryption (mock Kyber) with the robust key exchange capabilities of RSA.

Harvested Online Documentation & Reference Sources • https://en.wikipedia.org/wiki/List%20of%20computing%20and%20IT%20abbreviations • https://en.wikipedia.org/wiki/Hyphanet • https://en.wikipedia.org/wiki/UEFI • https://krprashant94.github.io/Hybrid-Cryptography-on-Cloud/ • https://github.com/hariPRO6/Secure-Safe/ • https://phigoro.com/blog/implementing-hybrid-encryption-in-python/ • https://github.com/aryxnkxushik/Secure-File-Storage-on-Cloud-Using-Hybrid-Cryptography • https://github.com/MarsadKibria/hybrid-crypto-file-encryption • https://hybrid-cryptography-on-cloud.readthedocs.io/en/latest/