. This REST service is authenticated using HMAC-SHA1 encrypted tokens. c Result. As a result, your CF script is base64 encoding a completely different value. Hash functions ensure that the message cannot be recovered using the hash. digest (key, msg, digest) ¶ Return digest of msg for given secret key and digest. The benefit of using KMAC128 k ( m) instead of H ( k ‖ m) is that there is no danger of such colliding uses. Here A will create a key (used to create Message Authentication Code) and sends the key to B. A subset of CMAC with the AES-128 algorithm is described in RFC 4493. HMAC has several advantages over other symmetric MACs, such as CBC-MAC, CMAC, or GMAC. 87, while the previous distinguishing attack on HMAC-MD5 reduced to 33 rounds takes 2126. ∙Message encryption. It is specified in NIST Special Publication 800-38B. 1 messages with a success rate of 0. The CMAC Validation System (CMACVS) specifies validation testing requirements for the CMAC mode in SP 800-38B. Remarks. How to. 7k 1 22 52. B has to check whether the ciphertext. Alternatives to HMAC-MD5 include HMAC-SHA256 [HMAC] [HMAC-SHA256] and [AES-CMAC] when AES is more readily available than a hash. Hence, they don't encrypt messages and are not encryption algorithms. The Data Authentication Algorithm, or DAA, is a block cipher MAC based on DES. A message authentication code algorithm takes two inputs, one is a message and another is a secret key which produces a MAC, that allows us to verify and check the integrity and authentication of the message. Validate that data has not been tampered with or has been corrupted ("Integrity") . g. Mn. It takes a single input -- a message -- and produces a message digest, often called a hash. The output of MD5 (Digest size) is always 128. You can work with either, but its recommended you work with the EVP_* functions. In cryptography, an HMAC (sometimes expanded as either keyed-hash message authentication code or hash-based message authentication code) is a specific type of message authentication code (MAC) involving a cryptographic hash function and a secret cryptographic key. HMAC utilizes a cryptographic hash function, such as MD5,. AES-GCM algorithm performs both encryption and hashing functions without requiring a seperate hashing algorithm, it is the latest Suite B Next Generation algorithm and probably not supported on as ASA 5505. Most HMAC implementations allow you to feed the input in multiple chunks, so you don't have to do any explicit string concatenation. Anybody who has this key can therefore be a verifier and signer. I've checked and I can confirm that your results can be obtained if we concatenate opad with hex-encoded hash. In HMAC, we have to apply the hash function along with a key on the plain text. CMAC is a message authentication code algorithm that uses block ciphers. The NIST provides test vectors in NIST: Block Cipher Modes of Operation - CMAC Mode for Authentication for AES128, AES192, and AES256. The input to the CCM encryption process consists of three elements. e. a) True b) False. (15 points) Show transcribed image text. HMAC is important because it has the ability to add a layer of security to using MAC, guarding against things like the length extension attack. 여느 MAC처럼 메시지의 데이터 무결성과 진본 확인을 동시에 수행하기 위해 사용할 수 있다. The keyed-HMAC is a security tool primarily used to ensure authentication and. If you use AES as "KDF" in this way, it is equivalent to sending an AES-ECB encrypted key that the recipient decrypts. Answer 1: HMAC or hash-based message authentication code was first characterized and distributed in 1996 and is presently utilized for IP security and SSL. Cryptography is the process of sending data securely from the source to the destination. However, security weaknesses have led to its replacement. The basic idea is to generate a cryptographic hash of the actual data. Being the de facto standard is a very. Follow. Then, M, R and S are sent to the recipient,. HMAC is a standard to produce a MAC with a cryptographic hash function as a parameter. Mac. Collision Resistance: Both hashing and HMAC. Here’s the best way to solve it. The rfc4493 only provides a test code for AES128. Concatenate a specific padding (the inner pad) with the secret key. 1 Answer. There are two types of Message Authentication Code (MAC): 1. Construction: HMAC is a hash-based construction, whereas CMAC is a cipher-based construction. HMAC Authentication. 5. For details, see DSA with OpenSSL-1. Things are rarely simple or obvious when working across languages; especially when one is . The main difference is that an HMAC uses two rounds of hashing instead of. g. We look at two MACs that are based on the use of a block cipher mode of operation. Improve this answer. Keyed vs. The HMAC and CMAC key types are implemented in OpenSSL's default and FIPS providers. or if you do not have access to Python prompt, deduce that looking at secrets ' source code which does have following line. Hash-based message authentication code (or HMAC) is a cryptographic authentication technique that uses a hash function and a secret key. a) Statement is correct. By which I mean I have to put a bunch of values together and HMAC-SHA1 encrypt them. message authentication code (MAC): A message authentication code (MAC) is a cryptographic checksum on data that uses a session key to detect both accidental and intentional modifications of the data. HMAC is commonly used in various protocols, including SSL/TLS, IPsec, and SSH. With AVX when processing parallel streams or with Intel SHA Extensions, it can be ok, up to a few gigabytes per second per core (e. They. Implement CMAC and HMAC using Python Cryptography library. In most cases HMAC will work best, but CMAC may work better where there is embedded hardware which has hardware accelleration for block ciphers. Both algorithms are widely used in various applications to provide secure message authentication. The algorithm makes use of a k-bit encryption key K and an n-bit constant K 1. It is usually quite fast. As with any MAC, it may be used to simultaneously verify both the data integrity. HMAC and NMAC based on MD5 without related keys, which distin-guishes the HMAC/NMAC-MD5 from HMAC/NMAC with a random function. I'm trying to decrypt kerberos traffic with wireshark for the learning purposes. Abstract. The first one is a. Contrary to you mentioning HMAC, GCM does use a MAC construction but it is called GMAC. MD5 was developed as an improvement of MD4, with advanced security purposes. 0, which is available in Master. CPython. HMACs and MACs are authentication codes and are often the backbone of JWT authentication systems. The HMAC and CMAC key types are implemented in OpenSSL's default and FIPS providers. HMAC utilizes a cryptographic hash function, such as MD5, SHA-1, or SHA-256, along with a secret key, to produce the authentication code. 92. . For information about creating multi-Region HMAC KMS keys, see Multi-Region keys in AWS KMS. There are some technical contexts where a MAC is sufficient (e. For a table that compares the AWS KMS API operations supported by each type of KMS key, see Key type reference. It can be used to ensure the authenticity and, as a result, the integrity of binary data. MAC stands for Media Access Control. You can find compatible crates (e. The receiver computes the MAC on the received message using the same key and HMAC function as were used by the sender,GMAC vs HMAC in message forgery and bandwidth. Hashing algorithms are as secure as the mathematical function is, while afterwards what matters is the bit length, bigger being preferred as it means less chances for collisions (multiple inputs ending up with the same hash output). Remarks. Note: CMAC is only supported since the version 1. See how this differs from other message authentication tools from expert Michael Cobb. The security bounds known ( this and this) for these algorithms indicate that a n -bit tag will give 2 − n / 2 security against forgery. The ACVP server SHALL support key confirmation for applicable KAS and KTS schemes. A will create a value using Ciphertext and key and the value is obtained. The hmac. The publication contains the specification for three allegedly cryptographically secure pseudorandom number. HMAC or hash-based message authentication code was first defined and published in 1996 and is now used for IP security and SSL. AES+CTR+HMAC Encryption and Authentication on an. This can be seen from the code. HMAC is a great resistance towards cryptanalysis attacks as it uses the Hashing concept twice. 9340 is way way larger than 340. Using a shared secret key, HMAC generates a cryptographic hash function on the message that you want to send. The CCMA test will cost about $100. NOVALOCAL with kvno 15, encryption type aes256-cts-hmac. } public abstract class HMAC : KeyedHashAlgorithm { new static public HMAC Create () { return Create ("System. Thus, HMAC can be used for any application that requires a MAC algorithm. There are different researches done. HMAC is a specific algorithm, however MAC can have two different meanings: MAC could be a generic term for a message authentication code, or it could mean a MAC that is build. Above we assumed that for 4 KB and 8 KB lookup tables in the GCM/GMAC, MULT operations are faster than one block encryption. 2. To calculate HMAC, the following steps are involved: Obtain a secret key known only to the sender and receiver. The first three techniques are based on block ciphers to calculate the MAC value. , MD5, SHA-1, in combination with a secret shared key. HMAC is. It then compares the two HMACs. A CMAC is essentially a CBC-MAC done right (refer to Authenticated Encryption and the use of a CBC-MAC on variable length messages). HMAC"); } new static public HMAC Create (string. Hash functions are not reversible. The advantage of. 1. CPython. Note that this assumes the size of the digest is the same, i. Abroad Education Channel :Specific HR Mock Interview : A seasoned professional with over 18 y. The Data Authentication Algorithm, or DAA, is a block cipher MAC based on DES. Simplified a good deal, a PRF is a secret keyed function such that an. Here is a table showing the differences of the possibilities for each primitive: Feature. HMACs vs. Alternatives to HMAC-MD5 include HMAC-SHA256 [HMAC] [HMAC-SHA256] and [AES-CMAC] when AES is more readily available than a. Concatenate a specific padding (the inner pad) with the secret key. So the term AES-HMAC isn't really appropriate. Basically, the way the attack works is this: The attacker sends a message, and an HMAC (really just a sequences of bytes the same length as the HMAC) and times the response from the decryption system. For AES, the key size k is 128, 192, or 256 bits. The main difference between CMAC and HMAC is that CMAC is a fixed-length hash while HMAC is a variable-length hash. . Cryptography is the process of sending data securely from the source to the destination. HMAC = hashFunc(secret key + message) In a messaging transaction between a client and a server involving HMAC, the client creates a unique HMAC or hash by hashing the request data with the private keys and sending it as part of a request. Note: CMAC is only supported since the version 1. Parameters:. Essentially, a MAC is an encrypted checksum generated on the underlying message that is sent along with a message to ensure. 8. 2: There are plenty of theoretical attacks on HMAC-MD4 and HMAC-MD5 (which usually means a practical attack is on the horizon; you should be using at least HMAC-SHA-1). 1 DES_DDD_Encrypt_Init function . Purpose of cryptography. 1 Answer. People also inquire as to what AES CMAC is. Federal Information Processing Standard (FIPS) Publication []. For CMAC and HMAC we have CMAC_Update and HMAC_Update. Syntax: hmac. Which MAC algorithm is faster - CBC based MAC's or HMAC - depends completely on which ciphers and hashes are used. GMAC is part of GCM; while CMAC is supported in the upcoming OpenSSL 1. So you need tell pycrypto to use the same mode as in CryptoJS:Difference in HMAC signature between python and java. The fundamental difference between the two calls are that the HMAC can only. CRC64 vs an 8-byte (64-bit) truncated HMAC or CRC32 vs a 4-byte (32-bit) truncated HMAC. CMAC is a block-cipher mode of operation that is commonly used with AES (Advanced Encryption Standard) and 3DES (Triple Data Encryption Standard) algorithms. The man page says this about it: Authenticated encryption with AES in CBC mode using SHA256 (SHA-2, 256-bits) as HMAC, with keys of 128 and 256 bits. HMAC Security • Security of HMAC relates to that of the underlying hash algorithm • If used with a secure hash functions (s. The advantage of utilizing a hash-based MAC rather than a MAC-based a. Clarification on hybrid encryption vs ECIES vs symmetric encrypt the message and then. To clarify, I shouldn't expect issues as long as our usage is with the higher level encryption types (2048 and AES-256 and SHA-256///) but we still have the question about which MAC algorithm is being used: HMAC KMAC or CMAC or is the answer, all three are being used. A HMAC is a specific kind of MAC defined by RFC 2104. HMAC keys have two primary pieces, an. HMAC is an excellent construction because it combines the benefits of both a MAC and the underlying hash. A MAC is also called a keyed hash. The server receives the request and regenerates its own unique HMAC. It is similar to HMAC, but instead of using a hash function, it uses a block cipher to produce a MAC for a message. See full list on geeksforgeeks. While MAC algorithms perform a direct calculation, HMAC involves an additional step of. The GHASH algorithm belongs to a widely studied class of Wegman-Carter polynomial universal hashes. HMAC uses an unkeyed collision-resistant hash function, such as MD5 or SHA1, to implement a keyed MAC. . From the description of CMAC and HMAC, given the key and the tag, I think it is easy to derive the CMAC message than the HMAC message. 9 MAC The Financial Institution (Wholesale) Message Authentication Standard (ANSI X9. /foo < foo. So, will CBC solve my purpose. Hash the result obtained in step 2 using a cryptographic hash function. 2. As Chris Smith notes in the comments, HMAC is a specific MAC algorithm (or, rather, a method for constructing a MAC algorithm out of a cryptographic hash function). Founder of Boot. The function is equivalent to HMAC(key, msg, digest). An HMAC is a kind of MAC. Rather than waste time here’s the code, in its long form. 1. bilaljo. HMAC, as noted, relies on a hash. Geração de um HMAC-SHA1Em criptografia, um HMAC (às vezes expandido como keyed-hash message authentication code (em português, código de autenticação de mensagem com chave hash) ou hash-based message authentication code (em português, código de autenticação de mensagem com base em hash) é um tipo específico de código de. What is the difference between a hash and an HMAC ? A hash uses a standard algorithm to derive the digest. The Difference Between HMAC and CMAC: Exploring Two Cryptographic Hash Functions MACs can be created from unkeyed hashes (e. CMAC. . HMAC and NMAC based on MD5 without related keys, which distin-guishes the HMAC/NMAC-MD5 from HMAC/NMAC with a random function. net. Message authentication code. Follow edited May 27, 2011 at 8:10. 1997年2月、IBMのKrawczykらにより提唱され、RFC 2104として公開されている。Courses. Second, what exactly is HMAC and how does it differ from Mac? HMAC is more secure than MAC because the key and message are hashed separately. g. For detecting small errors, a CRC is superior. You use an HMAC key to create signatures which are then included in requests to Cloud Storage. Here A will create a key (used to create Message Authentication Code) and sends the key to B. Testing Notes. My process of following: First I retrive keytab for the test user with kadmin. The main difference between MAC and HMAC is that MAC is a tag or a piece of information that helps to authenticate a message, while HMAC is a special type of MAC with a cryptographic hash function and a secret cryptographic key. At the risk of being overly reductionist, AES-SIV is basically a nonce misuse resistant variant of AES-CCM: Where AES-CCM uses CBC-MAC, AES-SIV uses CMAC, which is based on CBC-MAC but with a doubling step (left shift then XOR with the round constant). The ASCII art picture above applies as well with the difference that only step (4) is used and the SKCIPHER block chaining mode is CBC. CMAC requires three keys, with one key used for each step of the cipher block chaining. Name : Aditya Mandaliya Class : TEIT1-B2 Roll No : 46 Assignment No 5 1. Abstract and Figures. The results of sha1 encryption are different between python and java. From the viewpoint of hardware realization, the major differences between the CCMAC and HCMAC are those listed in Table 1. As a naive example: sha256 ('thisIsASe' + sha256 ('cretKey1234' + 'my message here')) Which is a simplified version of the function given. The same secret is used to create the MAC as is used to verify it. A message digest algorithm takes a single input, like a message and produces a message digest which helps us to verify and check the. CRC64 vs an 8-byte (64-bit) truncated HMAC or CRC32 vs a 4-byte (32-bit) truncated HMAC. 0. Abstract This document describes HMAC, a mechanism for message authentication using cryptographic hash functions. Whereas MACs use private keys to enable a message recipient to verify that a message has not been altered during transmission, signatures use a private/public key pair. One-key MAC ( OMAC) is a message authentication code constructed from a block cipher much like the CBC-MAC algorithm. HMAC Algorithm • HMAC consists of twin benefits of Hashing and MAC, and thus is more secure than any other authentication codes. Cifra 's benchmark shows a 10x difference between their AES and AES-GCM, although the GCM test also included auth-data. hmac. The actual mode is determined by the segment size. An HMAC is a kind of MAC. Quantum-Safe MAC: HMAC and CMAC. HKDF (master, key_len, salt, hashmod, num_keys = 1, context = None) ¶. Cryptography and Network Security Chapter 12 Fourth Edition by William Stallings Lecture slides by Lawrie Brown. The message authentication code (MAC) is generated from an associated message as a method for assuring the integrity of the message and the authenticity of the source of the message. HMAC. The hmac call gives you keyed hash of the string "data" using string "key" as the key and sha1 as the hash function. . MAC codes, like hashes, are irreversible: it is impossible to recover the original message or the key from the MAC code. It should be impractical to find two messages that result in the same digest. One possible reason for requiring HMAC specifically, as opposed to just a generic MAC algorithm, is that the. 9 KeyConfirmation. 4. Answer 1: HMAC or hash-based message authentication code was first characterized and distributed in 1996 and is presently utilized for IP security and SSL. It should be impractical to find two messages that result in the same digest. HMAC, when instantiated with SHA-1 or SHA-2, is generally taken to be a PRF as well as a MAC, so it is widely used in both contexts. An HMAC function is used by the message sender to produce a value (the MAC) that is formed by condensing the secret key and the message input. Improve this answer. The Difference Between HMAC and CMAC: Exploring Two Cryptographic Hash FunctionsHMAC is based on a hash function, while CMAC is based on a block cipher. Java Mac HMAC vs C++ OpenSSL hmac. Digital signatures are the public key equivalent of private key message authentication codes (MACs). Approved Algorithms Currently, there are three (3) approved* general purpose MAC. HMAC (and any other MAC) are totally different from Digital Signatures (RSA, DSA, ECDSA, EdDSA). Difference between AES CMAC and AES HMAC? Related. With an HMAC, you can use popular hashing algorithms like SHA-256, etc with a secret key to generate a Message Authentication Code. Furthermore, MAC and HMAC are two codes used in cryptography to pass the messages. ) Using CMAC is slower if you take into account the key derivation, but not much different. It is not urgent to stop using MD5 in other ways, such as HMAC-MD5; however, since MD5 must not be used for digital signatures, new protocol designs should not employ HMAC-MD5. The only difference is in the formal definition - a one time token is exactly that - once issued, it. The HMAC verification process is assumed to be performed by the application. 7. example, CBC(AES) is implemented with cbc. Jain. Hash codes can be secured to become a MAC in various ways: HMAC, CBC-MAC and CMAC are examples d. What is the difference between AES-CCM8 mode and AES-CCM mode? 1. 6). Regarding the contrast of hash function and MAC, which of the following statements is true? Compared to hash function, MAC involves a secret key, but it is often not secure to implement a MAC function as h(k, . After obtaining the key and tag for CMAC, an intruder can apply repeated decryption to get the blocks of the message until it represents a valid English text (assuming common case). So I guess the question is: are there any known algorithms - such as Grover's algorithm - that would significantly bring down the security of HMAC-SHA256 assuming a. Title: Microsoft PowerPoint - HMAC_CMAC_v2. d) Depends on the processor. In particular, it is a modified. HMAC is not the only MAC—there are others like Poly1305, CMAC, UMAC, etc. 8. 123 1 4. How does AES-GCM and AES-CCM provide authenticity? Hot Network Questions What is an electromagnetic wave exactly? How to draw this picture using Tikz How to parse上で話し合い Author's last name is misspelled online but not in the PDF. What are advantages/disadvantages for using a CMAC that proofs the integrity and authenticity of a message but doesn't encrypt the payload itself? Why should it be used instead of symmetric encrypted payload and CRC (CRC is encrypted as well)? This could also proof authenticity, integrity AND confidentially. CMAC and GMAC-4KB have similar results, but in terms of size CMAC is the best. Android (Java) method equivalent to Python HMAC-SHA256 in Hex. Let's take a. GCM is notoriously complex to implement securely, negating the conceptual simplicity of GHASH. HMAC Algorithm in Computer Network. This value Created by Ciphertext + Key = Message Authentication Code. So that the server can verify the data hasn’t been tampered with. 9340 is way way larger than 340. 1. HMAC: HMAC is a often used construct. RFC 2104 has issued HMAC, and HMAC has been made compulsory to implement in IP security. An HMAC also provides collision resistance. $egingroup$ Advantages of HMAC are speed, as stated in the fine answers; and small size of the authenticating token (128 bits or even much less, vs at least 1024 bits). It is an authentication technique that combines a hash function and a secret key. It must be a high-entropy secret, though not necessarily uniform. HMAC-SHA1の生成. 87, while the previous distinguishing attack on HMAC-MD5 reduced to 33 rounds takes 2126. To answer your question: yes, GMAC does have niche applications where it performs better than either HMAC or CMAC; however it might not make sense for you. Hash-based message authentication code, or HMAC, is an important building block for proving that data transmitted between the components of a system has not been tampered with. . In the authors’ study, they conduct a formal analysis of the TPM2. 11. HMAC, as noted, relies. Full Course: Authentication Codes (MACs). . For this, CMAC would likely run faster than. There are other flaws with simple concatenation in many cases, as well; see cpast's answer for one. c) Depends on the hash function. . In HMAC the function of hash is applied with a key to the plain text. But unlike the traditional MAC we talked about earlier, a hash-based message authentication code, or HMAC, is a type of MAC that uses two keys and hashes stuff twice. Note that conventional memory-comparison methods (such as memcmp function) might be vulnerable to timing attacks; thus be sure to use a constant-time memory comparison function (such as. HMAC is impervious to the birthday problem which halves the key strength to half of the hash output. 1. S. The HMAC_* routines are software based and don't use hardware. It is crucial that the IV is part of the input to HMAC. kadmin. TDES KO2 decrypt is. The MAC is typically sent to the message receiver along with the message. Both of these have their own pros and cons, which is why you should understand the differences between CMAC and. It is recommended to use a separate key for the HMAC but you may get away with using the same key as used for encryption as I haven't heard of any attacks that could attack a scheme with one key for HMAC (but if anybody switches it to CBC-MAC you're in trouble). Cifra 's benchmark shows a 10x difference between their AES and AES-GCM, although the GCM test also included auth-data. The FIPS 198 NIST standard has also issued HMAC. Authorized users can create, manage, and use the HMAC KMS keys in your AWS account. Cipher-based message authentication codes (or CMACs) are a tool for calculating message authentication codes using a block cipher coupled with a secret key. What MAC (Message Authentication Code) algorithms supported on OpenSSL? HMAC, GMAC and CMAC. Additionally, the code for the examples are available for download. What are advantages/disadvantages for using a CMAC that proofs the integrity and authenticity of a message but doesn't encrypt the payload itself? Why should it be used instead of symmetric encrypted. The claimed benchmark for SharkSSL puts CBC at a bit more than twice as fast as GCM, 2. In short: public class HMACSHA256 : HMAC {. 5. GMAC¶HMAC is a MAC (message authentication code), i. 6. 1 Answer Sorted by: 3 DAA is a specific deprecated government standard for authenticated encryption. . The first example uses an HMAC, and the second example uses RSA key pairs. It is due to by the inner. Available if BOTAN_HAS_CMAC is defined. , FIPS-approved and NIST-recommended) cryptographic algorithms and their individual components. I was primarily wondering if there is a difference between halving the. Your other question - why do we need to generate K1 and K2 from K - is a little bit harder to answer, but there's actually a very simple explanation: to eliminate any ambiguity in the message authentication. 6 if optimized for speed. BLAKE2b is faster than MD5 and SHA-1 on modern 64-bit systems and has a native keyed hashing mode that is a suitable equivalent for HMAC. Still nowhere close to your differential between straight AES and GCM. This property of mapping signif-icantly accelerates the learning process of CMAC, which is considered a main advantage of it comparing to other neural network models. This verb converts the clear key into operational form as a DATA key. It can be argued that universal hashes sacrifice some. Hash Based Message Authentication Code, HMAC, is an essential piece for. The high level APIs are typically designed to work across all algorithm types. Above we assumed that for 4 KB and 8 KB lookup tables in the GCM/GMAC, MULT operations are faster than one block encryption. comparison between number of clock cycles of HMAC_SHA256 and AES_256_CMAC is shown in Fig. CMAC is a block-cipher mode of operation that is. Published: 30 Aug 2011. So really, choosing between SHA1 and SHA256 doesn't make a huge difference. Additionally the Siphash and Poly1305 key types are implemented in the default provider. A secret key to the generation algorithm must be established between the originator of the message and its intended receiver(s). The primary problem here is that you are using createHash which creates a hash, rather than createHmac which creates an HMAC. dev. #inte. Learn more about message authentication. Both of these are strictly stronger security properties than what's required. import hmac import secrets print (hmac. The GMAC tag value is encrypted using the initial counter value, so the authentication tag - the MAC value generated by GMAC - does rely on the IV. It then compares the two HMACs. In new code, default to HMAC with a strong hash like SHA-256 or SHA-384. the CBC-HMAC must be used as Encrypt-then-MAC. c Result. 58. Keyless: Hashing does not rely on any external input, while HMAC requires a secret key in addition to the input data. A MAC may or may not be generated from a hash function though HMAC and KMAC are keyed hashes that based on a basic hash function, while AES-CMAC is one that relies on the AES block cipher, as the name indicate. Templates include all types of block chaining mode, the HMAC mechanism, etc. The key generation part which failed earlier also works. A single key K is used for both encryption and MAC algorithms. Java Mac HMAC vs C++ OpenSSL hmac.