Secure Hash Algorithm. Der Begriff Secure Hash Algorithm (kurz SHA, englisch für sicherer Hash-Algorithmus) bezeichnet eine Gruppe standardisierter kryptologischer Hashfunktionen. Diese dienen zur Berechnung eines Prüfwerts für beliebige digitale Daten (Nachrichten) und sind unter anderem die Grundlage zur Erstellung einer digitalen Signatur SHA (Secure Hash Algorithm) ist eine kryptographische Hashfunktion zur Ermittlung eines Prüfwerts (Fingerabdruck) digitaler Daten. (Bild: gemeinfrei / Pixabay ) Die Abkürzung SHA steht für Secure Hash Algorithm. Es handelt sich um kryptografische Hashfunktionen, mit denen sich die Integrität digitaler Daten sicherstellen lässt The Secure Hash Algorithms are a family of cryptographic hash functions published by the National Institute of Standards and Technology (NIST) as a U.S. Federal Information Processing Standard (FIPS), including: . SHA-0: A retronym applied to the original version of the 160-bit hash function published in 1993 under the name SHA. It was withdrawn shortly after publication due to an. SHA Characteristics. Cryptographic hash functions are utilized in order to keep data secured by providing three fundamental safety characteristics: pre-image resistance, second pre-image resistance, and collision resistance. . This security is provided by the nature of one-way functions, which is a key component of SHA A secure hash algorithm, often known simply as an SHA, is a hashing algorithm that is considered cryptographically secure. In general, hashing functions are used to sort and organize digital data into smaller, more categorized packets. Algorithms are the programs that drive the functions, and the security of these algorithms matters insofar as it controls how easily the data can be unlocked and rearranged. How secure things need to be usually depends on the circumstances. Many software.
SHA-2 (von englisch secure hash algorithm, sicherer Hash-Algorithmus) ist der Oberbegriff für die kryptologischen Hashfunktionen SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224 und SHA-512/256, die vom US-amerikanischen National Institute of Standards and Technology (NIST) als Nachfolger von SHA-1 standardisiert wurden SHA-256 (secure hash algorithm) is a cryptographic hash function with a digest length of 256 bits. It is a keyless hash function; that is, an MDC (Manipulation Detection Code). A message or data is processed by blocks of 512 = 16 × 32 bits, each block requiring 64 rounds. It generates a unique 256-bit (32-byte) signature for a string text. Block processing time for SHA-256 generally ranges. SHA-1 or Secure Hash Algorithm 1 is a cryptographic hash function which takes an input and produces a 160-bit (20-byte) hash value. This hash value is known as a message digest. This message digest is usually then rendered as a hexadecimal number which is 40 digits long. It is a U.S. Federal Information Processing Standard and was designed by the United States National Security Agency. SHA-1.
Secure Hash Algorithm 1. SECURE HASH ALGORITHM 2. Secure Hash Algorithm ( SHA ) Secure Hash Algorithm (SHA) was developed by NIST along with NSA. In 1993, SHA was published as a Federal Information Processing Standard. It has following versions- SHA-0 SHA-1 SHA-2 SHA-3 3. SHA-1 It works for any input message that is less than 264 bits. The output of SHA is a message digest of 160 bits in. A secure hash algorithm is actually a set of algorithms developed by the National Institutes of Standards and Technology (NIST) and other government and private parties. These secure encryption or file check functions have arisen to meet some of the top cybersecurity challenges of the 21st century, as a number of public service groups work with federal government agencies to provide better online security standards for organizations and the public Secure Hash Algorithm — YouTube Video; Current Recommendations for Key Length; Conclusion. Hashing algorithms can be pretty useful. However, IT is a really fast-changing industry and this entropy also extends to hashing algorithms. MD5, once considered really safe, now it's completely compromised. Then there was SHA-1, which is now unsafe. The same thing will surely happen to the widely. In cryptography, SHA-1 (Secure Hash Algorithm 1) is a cryptographic hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest - typically rendered as a hexadecimal number, 40 digits long. It was designed by the United States National Security Agency, and is a U.S. Federal Information Processing Standard Secure Hash Algorithms. In the past, many cryptographic hash algorithms were proposed and used by software developers. Some of them was broken (like MD5 and SHA1), some are still considered secure (like SHA-2, SHA-3 and BLAKE2). Let's review the most widely used cryptographic hash functions (algorithms). Secure Hash Functions . Modern cryptographic hash algorithms (like SHA-3 and BLAKE2) are.
The SHA (Secure Hash Algorithm) is a family of cryptographic hash functions. It is very similar to MD5 except it generates more strong hashes. However these hashes are not always unique, and it means that for two different inputs we could have equal hashes. When this happens it's called a collision. Chances of collision in SHA is less than MD5. But, do not worry about these collisions. Secure Hash Algorithm (SHA-1) produces a 160-bit hash value from an arbitrary length string. Like MD5, it is also used widely in applications such as SSH, SSL, S-MIME (Secure / Multipurpose Internet Mail Extensions), and IPSec. The main premise behind the security of SHA-1 is that it is computationally infeasible to find a message that corresponds to a given message digest, or to find two. Der Secure Hash Algorithm, kurz SHA, und alle seine Versionen, sind kryptografische Hash-Funktionen. Entwickelt wurde SHA vom US-Geheimdienst NSA im Auftrag der US-Standardisierungsbehöre NIST. SHA wurde zusammen mit dem Signaturverfahren DSA im Jahr 1991 der Öffentlichkeit vorgestellt. Obwohl Entwicklungen der NSA immer mit Misstrauen gesehen werden, stellte sich SHA als gute. SHA steht für Secure Hash Algorithm. Kryptografische Hashfunktionen sind mathematische Operationen, die mit digitalen Daten ausgeführt werden. Durch Vergleichen des berechneten Hash (der Ausgabe von der Ausführung des Algorithmus) mit einem bekannten und erwarteten Hashwert kann eine Person die Integrität der Daten bestimmen. Ein Einweghash kann aus einem beliebigen Datenelement.
This video is part of the Udacity course Intro to Information Security. Watch the full course at https://www.udacity.com/course/ud45 The Secure Hash Algorithm 1 (SHA-1) is a cryptographic computer security algorithm. It was created by the US National Security Agency in 1995, after the SHA-0 algorithm in 1993, and it is part of the Digital Signature Algorithm or the Digital Signature Standard (DSS) Der Secure Hash Algorithm (SHA1) ist eine weit verbreitete kryptographische Hashfunktion, die aus einer beliebigen Zeichkette einen 160-bit (20-byte)-Hashwert erzeugt. Diese dient zur Berechnung eines nach normalen Ermessen eindeutigen Prüfwerts für beliebige digitale Daten (Nachrichten) von maximal 2 64 − 1 Bit (≈ 2 Exbibyte) Länge und ist die Grundlage zur Erstellung einer digitalen.
You should always use proven secure hashing and encryption algorithms, rather than attempting to write your own. What's the process for criteria for an algorithm being proven? Is it necessarily a peer review process? Does an algorithm need to withstand exploit attempts for N amount of time by M many experts? Or, is there a mathematical proving process that security experts can apply on their. While some hash algorithms, including MD5 and SHA1, are no longer considered secure against attack, the goal of a secure hash algorithm is to render it impossible to change the contents of a file — either by accident, or by malicious or unauthorized attempt — and maintain the same hash value. You can also use hash values to determine if two different files have exactly the same content. If. As far as hashing algorithms go today, you'll stumble upon four distinct algorithms that are all part of the Secure Hash Algorithm (SHA) standard, designed by the NSA and standardized by NIST. SHA-0 SHA0 is the original version of SHA, released in 1993. It is no longer in use, since it contains some alleged weaknesses Secure Hash Algorithm (SHA) SHA published by the National Institute of Standards and Technology (NIST) is a family of cryptographic functions designed for keeping data secured. It's intended to be one-way functions, which means once the data are changed into the hash values, it's not possible to transform it back to the original data. Some of the SHA algorithms are SHA-1, SHA-2, and SHA-3.
Der Begriff secure hash algorithm (engl. für sicherer Hash-Algorithmus), kurz SHA, bezeichnet eine Gruppe standardisierter kryptologischer Hash-Funktionen. Diese dienen zur Berechnung eines eindeutigen Prüfwerts für beliebige elektronische Daten. Meist handelt es sich dabei um Nachrichten. Es soll praktisch unmöglich sein, zwei verschiedene Nachrichten mit dem gleichen SHA-Wert zu finden. This standard specifies hash algorithms that can be used to generate digests of messages. The digests are used to detect whether messages have been changed since the digests were generated. The Applicability Clause of this standard was revised to correspond with the release of FIPS 202, SHA-3 Standard: Permutation-Based Hash and Extendable-Output Functions, which specifies the SHA-3 family of. SHA stands for Secure Hashing Algorithm. It works by taking an input that can be any random size, and will produce an output that is a fixed size. With true SHA-512, the output will always be 512 bits. Why is this important?, [ SHA-256 algorithm. SHA stands for Secure Hash Algorithm. It is one of the number of cryptographic hash functions. SHA-256 is a member of the SHA-2 (Secure Hash Algorithm 2) family. SHA 2 is a set of cryptographic hash function which is the successor of SHA-1. It was designed by the United States NSA (National Security Agency) and was first published by National Institute of Standards and Technology (NIST) as a U.S federal standard (FIPS)
SHA-1, also known as Secure Hashing Algorithm - 1, is a mathematical cryptographic hash function. This algorithm was designed by the United States National Security Agency around 1995 and is a United States Federal Information, Processing Standard. SHA-1 takes an input and produces a sha1 hash key, also known as a message direct of 160-bits (20-byte). This is usually rendered as a 40 digit long hexadecimal number Our first hash function is the MD5 message-digest algorithm, developed way back in 1992. Java's MessageDigest makes this easy to calculate and can still be useful in other circumstances. However, over the last several years, MD5 was discovered to fail the fourth password hashing property in that it became computationally easy to generate collisions I did not ask what tool I should use to crypt my passwords, I asked for the most secure hashing algorithm. Blowfish is not a hashing algorithm. - Core Xii Jun 27 '11 at 12:36. 4 @Core Xii: While Blowfish isn't a hashing algorithmn, there is a password hashing algorithm that is called CRYPT_BLOWFISH in some circles. That's already covered in @Allan Jude answer and in my links above. You. Con il termine SHA (acronimo dell'inglese Secure Hash Algorithm) si indica una famiglia di cinque diverse funzioni crittografiche di hash sviluppate a partire dal 1993 dalla National Security Agency (NSA) e pubblicate dal NIST come standard federale dal governo degli USA (FIPS PUB 180-4). Come ogni algoritmo di hash, l'SHA produce un message digest, o impronta del messaggio, di lunghezza. SHA or Secure Hashing Algorithm is a family of cryptographic hash functions published by the National Institute of Standards and Technology (NIST) as a U.S. Federal Information Processing Standard (FIPS). Currently three algorithms are defined: SHA-1: A 160-bit hash function which resembles the earlier MD-5 algorithm. This was designed by the National Security Agency (NSA) to be part of the Digital Signature Algorithm. Cryptographic weaknesses were discovered in SHA-1, and the standard was.
. These are used to calculate a unique check for any digital data and are the basis for creating a digital signature. The check value is used to ensure the integrity of a message. If two messages give the same test value, is the equality of the messages which normally to be expected to be guaranteed. SHA (Secure Hash Algorithm) je rozšířená hašovací funkce, která vytváří ze vstupních dat výstup (otisk) fixní délky.Otisk je též označován jako miniatura, kontrolní součet (v zásadě nesprávné označení), fingerprint, hash (česky někdy psán i jako haš). Jeho hlavní vlastností je, že ze znalosti otisku je prakticky nemožné rekonstruovat vstupní data; malá.
The SHA (Secure Hash Algorithm) is one of the popular cryptographic hash functions. A cryptographic hash can be used to make a signature for a text or a data file. In this tutorial, let's have a look at how we can perform SHA-256 and SHA3-256 hashing operations using various Java libraries. The SHA-256 algorithm generates an almost-unique, fixed-size 256-bit (32-byte) hash. This is a one-way. Salted Secure Hash Algorithm (SALT) Salted secured hash algorithm helps protect password hashes against dictionary attacks by introducing additional randomness. Password hash salting is when random data - a salt - is used as an additional input to a hash function that hashes a password. The goal of salting is to defend against dictionary attacks or attacks against hashed passwords using a.
One-way hashing is better (we'll get to why in a second), but it is only as secure as is mathematically feasible. Let's take a look at one-way hashing algorithms and how computers handle them. Hashing. A hash by definition is a function that can map data of an arbitrary size to data of a fixed size. SHA2 is a hashing algorithm that uses.
• Security Hash Algorithm (SHA) was developed in 1993 by the National Institute of Standards and Technology (NIST) and National Security Agency (NSA). • It was designed as the algorithm to be used for secure hashing in the US Digital Signature Standard. • Hashing function is one of the most commonly used encryption methods. A hash is a special mathematical function that performs one-way. The SHA (Secure Hash Algorithm) Family designates a family of six different hash functions: SHA-0, SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512 [7, 8]. They take variable length input messages and hash them to fixed-length outputs. The first four operate on 512-bit message blocks divided into 32-bit words and the last two on 1024-bit blocks divided into 64-bit words. SHA-0 (the first version.
secure hash algorithm free download. Shadowsocks for Windows Shadowsocks for Windows is a free and open source, high-performance secured socks5 proxy designed t Hashing algorithms are used extensively in cryptography for encrypting keys or messages. Examples of popular cryptographic hashing algorithms include MD2, MD4, MD5, and SHA-1. Message Digest 5 (MD5) uses a 128-bit hash, and Secure Hash Algorithm (SHA) uses a 60-bit hash. The more bits in a hash, the greater the security of the encryption process In the SHA1 algorithm, this situation has been safer by generating 160-bit hash and by increasing to 280 the security level to prevent collision. SHA-1 (Secure Hash Algorithm 1) SHA1 uses an entry of up to 264 bits and generates 160-bit hash value, it can provide 80 bit security to not any conflict. This algorithm is only used for encryption. Secure Hash Algorithm (SHA) Dirk Fox Secure Hash Standard (SHS) Am 11.05.2003 veröffentlichte das US-ame-rikanische National Institute of Standards and Technology (NIST) den weltweit ersten Standard eines kryptographischen Hashver-fahrens, den Secure Hash Standard (SHS) [NIST93]. Die Funktionsweise des SHA ist einfach: Ein Datenstrom wird in Abschnitte von 160 bit Länge unterteilt, die. Secure Hash Algorithm (SHA) RACE Integrity Primitives Evaluation Message Digest (RIPEMD) Whirlpool; RSA; Topics: web security, Security, hashing, hashing algorithms, hashing algorithm, hash.
That means that the algorithm takes parameters itself, such as number of bits for the resultant hash value and number of rounds to do in producing the hashed result. The first number in the title of the Hash Function usually indicates the size of the hash result, such as 128 bit for haval128,3 and 160 bit for tiger160,4. The second number, however, indicates the number of rounds, such as 5 rounds for haval224,5 Secure Hash Algorithms are typically used with other cryptographic algorithms, such as digital signature algorithms and keyed-hash authentication codes, the generation of random numbers , or in key derivation functions. The algorithms specified in this document are called secure because it is computationally infeasible to (1) find a message that corresponds to a given message digest, or (2.
This section describes the JSON schema for a test vector set used with Secure Hash Algorithm (SHA) algorithms.¶ The test vector set JSON schema is a multi-level hierarchy that contains meta data for the entire vector set as well as individual test vectors to be processed by the ACVP client It was designed by Jean-Philippe Aumasson and Daniel J. Bernstein as a fast and secure keyed hash algorithm. It's used by Ruby, Perl, OpenDNS, Rust, Redis, FreeBSD and more. The C reference implementation has been released under CC0 license (public domain). Quote from SipHash's site: SipHash is a family of pseudorandom functions (a.k.a. keyed hash functions) optimized for speed on short. SHA steht für Secure Hash Algorithm und ist eine kryptographische Funktion zum Vergleich von eindeutigen Prüfsummen (Hashes). Die SHA-Verschlüsslung lässt keinen Rückschluss auf die ursprüngliche Zeichenkette zu, denn der verschlüsselte Text wird in eine eindeutige Kombination aus Zahlen und Ziffern. Das Ergebnis nennt sich SHA Hash The Secure Hash Algorithm (SHA) is a cryptographic hashing algorithm specified by the National Institute of Standards and Technology (NIST) in the Federal Information Processing Standards Publication 180 (FIPS PUB 180). The SHA family of algorithms is heavily employed in many of the most common cryptographic applications today. Primary usages of SHA include data integrity, message. Hash algorithm in ipsec VPN: Secure & User-friendly Configured Networks (VPN) Use Modes of IPSec Key Exchange Security - 3DES. Comments: 4894 VPN Consortium For instance, which encryption the IPsec hash algorithm World Network Working Group — Encryption algorithms for Comments: 4894 VPN Protocols - WatchGuard RFC the Hash algorithm drop-down key known protocols vet the mathematics to.
Hashing algorithms are an important weapon in any cryptographer's toolbox. They are everywhere on the internet, mostly used to secure passwords, but they also make up an integral part of most cryptocurrencies such as Bitcoin and Litecoin.. The main feature of a hashing algorithm is that it is a one-way function - you can get the output from the input but you can't get the input from the. Which algorithm creates the most secure hashes? There is little widespread agreement about the most secure hashing algorithm, as evidenced by the wide variation of hashing algorithms in use. Bitcoin and other cryptocurrencies rely on RipeMD, while the tried-and-true MD standard still enjoys widespread use (although its propensity for hash collisions reveal it as more tried than true. The abbreviation SHA is the Secure Hash Algorithm, and 256 means that the cryptocurrency algorithm generates a 256-bit hash, i.e., a string of 256 bits. The hash rate for SHA-256-based cryptocurrencies is calculated in units of Gigahash per second (GH/s). It takes six to ten minutes to create a block. The US National Security Agency invented the SHA-256 algorithm in 2001. It is part of the SHA. US Secure Hash Algorithm 1 (SHA1) Autor(en): P. Jones, D. Eastlake 3rd. The purpose of this document is to make the SHA-1 (Secure Hash Algorithm 1) hash algorithm conveniently available to the.
Secure Hash Algorithm is a cryptographic hash function developed by the NSA. Their first algorithm, SHA-0 (released in 1993) has been compromised years ago. SHA-1 (1995) generates a 160-bit (20-byte) hash output. SHA-1 improved MD5 by just increasing the hash value to a 40 digits long hexadecimal number. The algorithm also became compromised in 2005 as there were discovered theoretical. La família SHA (Secure Hash Algorithm, Algorisme de Hash Segur) és un sistema de funcions hash criptogràfiques publicades pel National Institute of Standards and Technology (NIST). El primer membre de la família es va publicar el 1993 i se'l va anomenar de forma oficial SHA.No obstant això, avui en dia i de forma no oficial se l'anomena SHA-0, per evitar confusions amb els seus successors
2 SHA-1: the Secure Hash Algorithm standard considers it as the second one version. The SHA-zero being the first. 160-bit outputs is the featureof SHA-1 hashing algorithm. It is also one of the foremost algorithms which started to update MD5. The updates were done after finding the vulnerabilities. It gained massive use and acceptance by the users. FIPS 140 compliant hashing algorithm was the. Secure Hash Algorithm Ir a la NIST ha actualizado el borrador de la publicación FIPS 202, estándar SHA-3 por separado del estándar Secure Hash (SHS) [2 SHA-0. A lo largo de su historia, se han puesto a prueba esta familia de algoritmos: Un retrónimo aplicado a la versión original de la función hash de 160 bits publicada en 1993 con el nombre SHA. Fue retirado poco después de su.
. So sind zum Beispiel die Passwörter für den Shell-Zugang zu Unix und kompatiblen Systemen standardmäßig nur als Hashwert und nicht im Klartext in der Passwortdatei gespeichert For older applications that were built using less secure hashing algorithms such as MD5 or SHA-1, these hashes should be upgraded to more modern and secure ones. When the user next enters their password (usually by authenticating on the application), it should be re-hashed using the new algorithm. It would also be good practice to expire the users' current password and require them to enter a.
MD4 - MD4 is a self-loathing hash algorithm, created in 1990, even its creator, Ronald Rivest, admits it has security problems. The 128-bit hashing algorithm made an impact though, it's influence can be felt in more recent algorithms like WMD5, WRIPEMD and the WHSA family. MD5 - MD5 is another hashing algorithm made by Ray Rivest that is known to suffer vulnerabilities. It was created in. Secure Hash Algorithm (SHA-512) 1. Secure Hash Algorithm-512 (SHA-512) Course Code: CSE-6304 Course Id: Network Security Presented To Presented By Mr. Md. Shohidul Islam Md. Shariful Islam Assistant Professor Student id: 142419-P Department of CSE, DUET Session: 2014-15 1 April 5, 201 Hash algorithm in ipsec VPN: Stream safely & unidentified Looking to exploit security. The best path to know if a Hash algorithm in ipsec VPN will forge for you is to anguish IT out American state your own home. accompany if you can access all the sites and work that you need. feat out if the interface is usable, and if the speeds in your area are acceptable
Implementation of secure hash algorithm-1 using FPGA. Int. J. Inf. Comput. Technol. 3 (2013), 757--764. Google Scholar; Ian Janik and Mohammed A. S. Khalid. 2016. Synthesis and evaluation of SHA-1 algorithm using altera SDK for OpenCL. In Proceedings of the IEEE 59th International Midwest Symposium on Circuits and Systems (MWSCAS'16). IEEE, 1--4. Google Scholar; Harris E. Michail, George S. A secure hash algorithm is a set of algorithms developed by the National Institutes of Standards and Technology (NIST) and other government and private parties. These secure encryptions or file.
. Indeed, because virtually every other widely used hash function had been found to have substantial cryptanalytic weaknesses, SHA was more or less the last remaining standardized hash algorithm by 2005 In it's place, you'll probably see SHA, or the Secure Hash Algorithm. This is a hashing algorithm created by the National Security Agency of the United States. And it's part of the Federal Information Processing Standard or FIPS. The first variant of SHA was SHA-1. It had a 160-bit digest that was created for the hash. But unfortunately in 2005 there were collisions found with SHA-1. SHA. A hashing algorithm creates a hash code, also called a message digest or message fingerprint. As we explained in Chapter 12, hash codes are of limited use for communications security, because Eve can replace both the hash code and the message that Bob receives, but they are an essential element of digital signatures, which we discuss in Chapter 16
Hashing Algorithm. Input# x 143. Hash Value. 1,525,381. You can see how hard it would be to determine that the value 1,525,381 came from the multiplication of 10,667 and 143. But if you knew that the multiplier was 143, then it would be very easy to calculate the value 10,667. Public-key encryption is actually much more complex than this. Hash, hash baby - Secure Hash Algorithm in NAV/365BC (and a little more) 2 Comments / Technology. Mostly web services offered through an API do require special ways of authorisation. Recently I've came across the Royal Mail API which doesn't work without a combination of Base64-encoding and a SHA-1 encryption. The Royal Mail Shipping API does require a security header based on the.
Basically, it's a processing unit that takes in data of arbitrary length and gives you the output of a fixed length - the hash value. The length of the output or hash depends on the hashing algorithm. Generally speaking, the most popular hashing algorithms or functions have a hash length ranging from 160 to 512 bits Secure hash algorithms are typically used with other cryptographic algorithms, such as digital signature algorithms and keyed hash authentication codes, or in the generation of random numbers [RFC4086]. The four algorithms specified in this document are called secure because it is computationally infeasible to (1) find a message tha However, even hashing passwords with a salt is not secure with the 'normal' hashing algorithms (such as MD5 and the SHA family), since they are optimized for speed, which allows hackers compute 2300 million hashes per second (brute force). There are hashing algoritms that are safer to use because they are much more computational intensive, such as PBKDF2, Bcrypt, PBMAC, and scrypt. These.
. The purpose of this. The Secure Hash Algorithm (SHA) is a one-way Cryptographic Hash Function. There are actually several different forms of the Secure Hash Algorithm: SHA - A retronym applied to the original version of the 160-bit hash function published in 1993 under the name SHA
The NSA (yes, that NSA), has long been a pioneer of hashing algorithm standards, with their initial proposal of the Secure Hashing Algorithm or SHA1, creating 160 bit fixed-length outputs. Approved hash algorithms for generating a condensed representation of a message (message digest) are specified in two Federal Information Processing Standards: FIPS 180-4, Secure Hash Standard and FIPS 202, SHA-3 Standard: Permutation-Based Hash and Extendable-Output Functions. FIPS 180-4 specifies seven hash algorithms: SHA-1 (Secure Hash. RFC 3174 US Secure Hash Algorithm 1 (SHA1) September 2001 Suppose a message has length l < 2^64. Before it is input to the SHA-1, the message is padded on the right as follows: a. 1 is appended. Example: if the original message is 01010000, this is padded to 010100001 The Secure Hash Algorithm takes a message of less than 2 64 bits in length and produces a 160-bit message digest which is designed so that it should be computationaly expensive to find a text which matches a given hash. ie if you have a hash for document A, H(A), it is difficult to find a document B which has the same hash, and even more difficult to arrange that document B says what you want. Small program to calculate SHA-1 or SHA-256 hashes of files - striezel/secure-hash-algorithm