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GCM Mode

Galios/Counter Mode, or GCM Mode, is a mode of operation that uses a universal hash function over a binary Galois field to provide authenticated encryption. The mode is defined in NIST's SP 800-38D , and P1619 The mode of operation that uses GCM as a stand-alone message authentication code is denoted as GMAC. An example use of GCM for network security is provided in Section 5, which shows how the inputs and outputs can be used in a typical cryptographic application. 2.2

GCM Mode - Crypto++ Wik

Galois/Counter Mode(ガロア カウンター モード、GCM)は、ブロック暗号の暗号利用モードの一つであり、認証付き暗号の一つである。 GCMは 認証付き暗号 の一つであり、データ保護と認証(完全性確認)の両方の機能を提供する GCM mode provides both privacy (encryption) and integrity. To provide encryption, GCM maintains a counter; for each block of data, it sends the current value of the counter through the block cipher. Then, it takes the output of the block cipher, and exclusive or's that with the plaintext to form the ciphertext 블록 암호 운용 방식. 위키백과, 우리 모두의 백과사전. 암호학 에서 블록 암호 운용 방식 ( 영어: block cipher modes of operation )은 하나의 키 아래에서 블록 암호 를 반복적으로 안전하게 이용하게 하는 절차를 말한다. 블록 암호는 특정한 길이의 블록 단위로.

Use the following commands in order to activate Creative Mode. cheat GiveCreativeMode or GCM to activate it for yourself. cheat GiveCreativeModeToTarget or GCMT to toggle Creative Mode for the player you are targeting. cheat GiveCreativeModeToPlayer <playerid> or GCMP to toggle Creative Mode for a player by their ID GCM mode¶ Galois/Counter Mode, defined in NIST SP 800-38D. It only works in combination with a 128 bits cipher like AES. The new() function at the module level under Crypto.Cipher instantiates a new GCM cipher object for the relevant base algorithm. Crypto.Cipher.<algorithm>.new(key, mode, *, nonce=None, mac_len=None

GCM mode (Galois/Counter Mode) is a mode of operation for symmetric key cryptographic block ciphers. It is an authenticated encryption algorithm designed to provide both authentication and secrecy. GCM mode is defined for block ciphers with a block size of 128 bits. GMAC is an authentication-only variant of the GCM What is GCM? Galois Counter Mode (of operation) (usually seen as AES-GCM) If playback doesn't begin shortly, try restarting your device. Videos you watch may be added to the TV's watch history and..

The GCM mode we implement conforms to the IPsec Encapsulating Security Payload (ESP) protocol in tunnel mode as described in RFC 4106 [5]. Though we do not include the code of our implementation in the paper, we describe it a high-level. For simplicity we have explained the encryption process in this paper This Recommendation specifies the Galois/Counter Mode (GCM), an algorithm for authenticated encryption with associated data, and its specialization, GMAC, for generating a message authentication code (MAC) on data that is not encrypted. GCM and GMAC are modes of operation for an underlying approved symmetric key block cipher There's an updated video at https://www.youtube.com/watch?v=R2SodepLWLgOr search for 104 Galois/Counter Mode (GCM) and GMAC: Get a Gut Level UnderstandingGCM.. GCM, called GMAC, is simply an authentication mode on the input data. In the rest of this document, statements about GCM also apply to GMAC. GCM provides stronger authentication assurance than a (non-cryptographic) checksum or error detecting code; in particular, GCM can detect both 1) accidental modifications of the data and 2

Galois/Counter Mode Explained. In cryptography, Galois/Counter Mode (GCM) is a mode of operation for symmetric-key cryptographic block ciphers which is widely adopted for its performance. GCM throughput rates for state-of-the-art, high-speed communication channels can be achieved with inexpensive hardware resources. The operation is an authenticated encryption algorithm designed to provide. In simple terms, Galois Counter Mode (GCM) block clipper is a combination of Counter mode (CTR) and Authentication it's faster and more secure with a better implementation for table-driven field.. AES-GCM is an authenticated encryption mode that uses the AES block cipher in counter mode with a polynomial MAC based on Galois field multiplication. In order to explain why AES-GCM sucks, I have to first explain what I dislike about the AES block cipher Only GCM mode should use this parameter, as a simple truncation works as expected. CCM, which uses a formatting function, requires the digest size to be known at compile time and declared as a template parameter. So CCM mode should not change the default value. The final two parameters, macChannel and padding, should not be modified

Friends, We have received Vulnerability scan report for our WS_FTP server and suggested below actions.. 1. SSH Server CBC Mode Ciphers Enabled - Disable CBC mode cipher encryption, and enable CTR or GCM cipher mode encryption. The following client-to-server Cipher Block Chaining (CBC · Hi, To disable a certain cipher suite in SCHANNEL, we. Galois/counter mode (GCM) combines the well-known counter mode of encryption with the new Galois mode of authentication. The key feature is the ease of parallel computation of the Galois field multiplication used for authentication. This feature permits higher throughput than encryption algorithms. GCM is defined for block ciphers with a block size of 128 bits. Galois message authentication. def test_encrypt(self, tv): self._id = Wycheproof Encrypt GCM Test # + str(tv.id) try: cipher = AES.new(tv.key, AES.MODE_GCM, tv.iv, mac_len=tv.tag_size, **self._extra_params) except ValueError as e: if len(tv.iv) == 0 and Nonce cannot be empty in str(e): return raise e cipher.update(tv.aad) ct, tag = cipher.encrypt_and_digest(tv.msg) if tv.valid: self.assertEqual(ct, tv.ct) self.assertEqual(tag, tv.tag) self.warn(tv For MODE_EAX, MODE_GCM and MODE_SIV there are no restrictions on its length (recommended: 16 bytes). For MODE_CCM, its length must be in the range [7..13]. Bear in mind that with CCM there is a trade-off between nonce length and maximum message size. Recommendation: 11 bytes. For MODE_OCB, its length must be in the range [1..15] (recommended: 15) The modes include EAX, CCM and GCM mode. Using AEAD modes is nearly identical to using standard symmetric encryption modes like CBC, CFB and OFB modes. As with standard symmetric encryption you will need to know the following: Algorithm (currently only AES is supported

This post will cover Galois Counter Mode (GCM) which unlike RAC provides both authenticity and confidentiality. This is an authenticated encryption algorithm and defined for block sizes of 128 bits RFC 4106 GCM ESP June 2005 2.AES-GCM GCM is a block cipher mode of operation providing both confidentiality and data origin authentication. The GCM authenticated encryption operation has four inputs: a secret key, an initialization vector (IV), a plaintext, and an input for additional authenticated data (AAD) What is GCM (Galois Counter Mode)? posted July 2015. In this video I'm explaining what is that Galois Counter Mode that provides Authenticated Encryption with Associated Data (AEAD). You must have heard it combined with AES, and maybe used in TLS,. 위키백과, 우리 모두의 백과사전. 암호학 에서 갈루와/카운터 모드 (Galois/Counter Mode, GCM)는 성능을 위해 널리 채택된 대칭 키 암호 블록 암호 의 운용 방식 이다. 저렴한 하드웨어 자원을 가지고 최신의 고속의 통신 채널을 위한 GCM 처리 속도를 달성할 수 있다. 이.

Intel® Carry-Less Multiplication Instruction and its Usage for Computing the GCM Mode - Rev 2.02 . Published: 04/13/2011 Last Updated: 04/13/2011 Introduction. Intel® PCLMULQDQ instruction is a new instruction available beginning with the all new. The GCM mode uses a counter, which is increased for each block and calculated a message authentication tag (MAC code) after each processed block. The final authentication tag is calculated from the last block. Like all counter modes, GCM works as a stream cipher, and so it is essential that a different IV is used at the start for each stream. GCM and CBC modes internally work quite differently; they both involve a block cipher and an exclusive-or, but they use them in different ways. In CBC mode, you encrypt a block of data by taking the current plaintext block and exclusive-oring that wth the previous ciphertext block (or IV), and then sending the result of that through the block cipher; the output of the block cipher is the.

What is a GCM? Numerical models (General Circulation Models or GCMs), representing physical processes in the atmosphere, ocean, cryosphere and land surface, are the most advanced tools currently available for simulating the response of the global climate system to increasing greenhouse gas concentrations (criterion 1 -- see list here ) AES-GCM is a block cipher mode of operation that provides high speed of authenticated encryption and data integrity. Todays, the level of privacy protection is insufficient and make the data is been hacked easily. The AES-GCM algorithm encrypts or decrypts with 128-bit, 192-bit or 256- bit of cipher key AES in either CBC or GCM mode with 256-bit keys (such as AES/GCM/NoPadding) MessageDigest: SHA-2 family (eg, SHA-256) Mac: SHA-2 family HMAC (eg, HMACSHA256) Signature: SHA-2 family with ECDSA (eg, SHA256withECDSA GCM (аббр. от англ. Galois/Counter Mode — счётчик с аутентификацией Галуа) — широко применяющийся. The Galois/Counter Mode (GCM) of operation for block ciphers was designed to meet the need for an authenticated encryption mode that can efficiently achieve speeds of 10 gigabits per second and higher in hardware, can perform well in software, and is free of intellectual property restrictions

Galois/Counter Mode (GCM) - IB

  1. The command: cheat gcm should work. There is also a line for bShowCreativeMode=False in the game.ini. I haven't tested it but changing that to true should give you a button on the escape menu to activate creative mode like it does for Ark
  2. AES GCM 256 Encryption in Javascript. 0. I want to implement the Javascript equivalent of Java AES GCM 256 code. Java code is as follows: public class AES { private static final int GCM_IV_LENGTH = 12; private static final int GCM_TAG_LENGTH = 16; private static final String GIVEN_KEY = ; public static String encrypt (String text) throws.
  3. AES-GCM Encryption with C#. Here is example how can you use encryption with AES GCM with C#. Its currently supported in .NET Core 3.0, 3.1 and .NET Standard 2.1. For .NET Framework you will need to use CBC. This code and more is awailable in my nuget package MayMeow.Cryptography. So How to encrypt data
  4. 29 * The Galois/Counter Mode (GCM) is an authenticated encryption algorithm 30 * designed to provide both data authenticity (integrity) and confidentiality. 31 * Refer to SP 800-38D for more detail

Galois/Counter Mode (GCM) ist ein Betriebsmodus, in dem Blockchiffren für eine symmetrische Verschlüsselungsanwendung betrieben werden können. Als wesentliche Eigenschaft bietet er Authenticated Encryption with Associated Data (AEAD), also einen authentifizierten Verschlüsselungsmodus mit assoziierten Daten, um sowohl die Authentifikation als auch die Verschlüsselung von Nachrichten zu. 국제 표준화 기구인 ISO/IEC와 NIST(National Institute of Standards and Technology)에서는 정보 유출 방지 및 정보의 유효성 인증을 위해 다양한 암호 기법들을 표준으로 권고하고 있다. 그 중 NIST SP 800-38D에서 표준으로 권고된 GCM(Galois/Counter Mode) 인증 암호화 모드는 블록암호의 CTR 운영모드와 GHASH를 이용하여.

GCM Mode - GitHub Page

AEAD Cipher(CCM, GCM) : 네이버 블로

  1. TL;DR if you're reading this in 2020, applications should be using GCM mode. CCM (Counter with CBC-MAC) Message authentication (via CBC-MAC) is done on the plaintext not the ciphertext. (This is generally not a desireable feature.) On the encrypt operation, the encryption and MAC could happen in parallel, but generally do not (typically because there is just one AES engine in a chip, just one.
  2. imized. Sign in to view. Copy link Quote reply Owner Author AndiDittrich commented Oct 24, 2019. the size of the.
  3. TL;DR If you only have 5 seconds to pick only one, go with AES-GCM. Most systems/libraries do both AES-GCM and ChaCha20-Poly1305 out-of-the-box. AES-GCM (Galois Counter Mode) The most widely used block cipher worldwide. Mandatory as of TLS 1.2 (2008) and used by default by most clients
  4. But the problem is not that. Indeed, using random IV's for GCM mode is a bad choice, if no other precautions are taken. The developer can use crypto.randomBytes or any other PRNG for IV's if they store them such that the developer or the storage mechanism enforce a unique constraint on IVs
  5. - GCM (Galois Counter Mode) -CMAC - KEY WRAP ARC4 DES, TripleDES. Supported modes are: - ECB (Electronic Codebook Mode) - CBC (Cipher-Block Chaining) HASH functions with HMAC support: -MD5 -SHA-1 - SHA-224 - SHA-256 Random engine based on DRBG-AES-12
  6. If using GCM (Galois/Counter Mode), no authentication algorithm is required because authentication is included with GCM encryption. If not using GCM, the following options are supported: HMAC-SHA-256-128 (recommended) HMAC-SHA1-96. IPSec session key lifetime: 3600 seconds (1 hour) Perfect Forward Secrecy (PFS
  7. GISS GCM Model II. The Goddard Institute for Space Studies General Circulation Model II, described fully by Hansen et al. (1983), is a three-dimensional global climate model that numerically solves the physical conservation equations for energy, mass, momentum and moisture as well as the equation of state.. Model Description. The standard version of this model has a horizontal resolution of 8.

When using symmetric encryption, you should be favoring authenticated encryption, such as AES-GCM (Galois/Counter Mode), rather than unauthenticated encryption, such as AES-CBC (Cipher Block Chaining).. Authenticated encryption provides you with confidentiality and an additional integrity check, allowing you to defend against various attacks based on the chosen-ciphertext attack AES是一种对称加密算法,它的相关概念在此不赘述。GCM ( Galois/Counter Mode) 是对称加密的一种加密模式。在介绍AES-GCM之前,我们先了解一些相关概念。下文中出现的符号:Ek使用秘钥k对输入做对称加密运算XOR异或运算Mh将输入与秘钥h在有限域GF(2^128)上做乘 Friends, We have received Vulnerability scan report for our WS_FTP server and suggested below actions.. 1. SSH Server CBC Mode Ciphers Enabled - Disable CBC mode cipher encryption, and enable CTR or GCM cipher mode encryption. The following client-to-server Cipher Block Chaining (CBC) algorithms are supported : 3des-cbc aes128-cbc aes192-cbc aes256-cbc blowfish-cb Note that GCM mode has a uniqueness requirement on IVs used in encryption with a given key. When IVs are repeated for GCM encryption, such usages are subject to forgery attacks. Thus, after each encryption operation using GCM mode, callers should re-initialize the cipher objects with GCM parameters which have a different IV value

Galois / Counter Mode (GCM) Cipher | Wireless On the Go

Please support sm4-gcm mode pls. This is slightly beyond a good first issue I suspect. The place I'd start would be the ARIA GCM code in providers/implementations/ciphers. Copy the three files, and change ARIA to SM4 throughout AES-GCM [1] combines AES-CTR mode for the encryption, and the GHASH algorithm for the authentication. The GHASH algorithm is a special form of the Carter-Wegman polynomial evaluation MAC. Each 16-bytes block of the authenticated data is multiplied by a different power of the hash key (H), where computations occur in some. AES-GCM is a block cipher mode of operation that provides high speed of authenticated encryption and data integrity. In GCM mode, the block encryption is transformed into stream encryption, and therefore no padding is needed.The Additional Authenticated Data (AAD) will not be encrypted but used in the computation of Authentication Tag

GCM (Galios/Counter Mode) is a mode of operation that uses a universal hash function over a binary Galois field to provide authenticated encryption. The mode is defined in NIST's SP 800-38D, and P1619. GCM is a high performance mode which offers both pipelining and parallelizatio GCM can also provide authentication assurance for additional data (of practically unlimited length per invocation) that is not encrypted. If the GCM input contains only data that is not to be encrypted, the resulting specialization of GCM, called GMAC, is simply an authentication mode for the input data Welcome to GTA5-Mods.com. Select one of the following categories to start browsing the latest GTA 5 PC mods 파일:GCM-Galois Counter Mode with IV.svg. English: Gallois Counter Mode block diagram with initialization vector, adapted from a diagram by NIST Benchmarking AES-GCM on GPUs with OpenCL. Contribute to michaeljclark/aes-gcm development by creating an account on GitHub

Cipher Block Modes - Practical Cryptography for Developer

AES-GCM mode should be available to most modern JREs and Android newer than v2.3 (although only fully functional on SDK 21+). If it happens to be not available install a custom crypto provider like BouncyCastle, but the default provider is usually preferred. We choose an authentication tag of size 128 bit GCM is an authenticated-encryption block cipher mode proposed by David McGrew and John Viega [3, 4]. NIST is currently considering standardizing additional authenticated-encryption modes of operation, and GCM is one of the candidates. GCM encrypts the message using the block cipher in counter mode, and computes the authenticatio In cryptography, Galois/Counter Mode (GCM) is a mode of operation for symmetric-key cryptographic block ciphers which is widely adopted for its performance. GCM throughput rates for state-of-the-art, high-speed communication channels can be achieved with inexpensive hardware resources. The operation is an authenticated encryption algorithm designed to provide both data authenticity (integrity.

GCM is an authenticated encryption mode with additional data (often referred to as AEAD). GCM is a cipher mode that can be applied to any symmetric encryption algorithm with a 16-byte block size, such as AES and Twofish. In GCM mode, the block encryption algorithm is transformed into a stream encryption algorithm, and therefore no padding. GCM (Galois Counter Mode) is a mode of operation for symmetric key cryptographic block ciphers. GCM is ideal for protecting packets of data because it has low latency and a minimum operation overhead. In 2015, Gueron and Lindell described AES-GCM as one of the most popular authenticated encryption schemes today due to its impressive speed gcm의 하나 이상의 정의가있을 수 있습니다, 그래서 하나 하나 gcm의 모든 의미에 대한 우리의 사전에 체크 아웃. 영어에서 정의: Galois/Counter Mode GCM 의 다른 의

General circulation model - Wikipedi

AES-GCM Encryption/Decryption. GCM is a block cipher counter mode with authentication. A Counter mode effectively turns a block cipher into a stream cipher, and therefore many of the rules for stream ciphers still apply. GCM mode provides both privacy (encryption) and integrity. GCM uses an IV (or Nonce General circulation model (GCM) is a mathematical representation of atmospheric, oceanic, and continental processes with its interactions. These models are limited by complexity and uncertainty as well as nonlinear interactions among atmospheric and oceanic processes (Hillel and Rosenzweig, 1989 )

AES-GCM authenticated encryption. AES with Galois/Counter Mode (AES-GCM) provides both authenticated encryption (confidentiality and authentication) and the ability to check the integrity and authentication of additional authenticated data (AAD) that is sent in the clear. AES-GCM is specified in NIST Special Publication 800-38D [ SP800-38D ] BCRYPT_CHAIN_MODE_GCM: LChainingModeGCM Sets the algorithm's chaining mode to Galois/counter mode (GCM).Windows Vista: This value is supported beginning with Windows Vista with SP1. BCRYPT_CHAIN_MODE_NA: LChainingModeN/A The algorithm does not support chaining. BCRYPT_DH_PARAMETERS. LDHParameter disable CBC mode cipher encryption, and enable CTR or GCM cipher mode encryption This means that if two machines are connecting to each other (without overriding the default ciphers through configuration options), they will always use the aes128-ctr cipher to encrypt their connection

encryption - What is the difference between CBC and GCM mode? - Cryptography Stack

GCM means Galois Counter Mode. GCM is an acronym for Galois Counter Mode. Share this. Have you found the page useful? Please use the following to spread the word: Do you enjoy All Acronyms as much as we do? Ready to support us?. WIZDOME 통합관리시스템. This site, only users who are WIZDOME inc. employees and authorization can be used, has been recorded to monitor and log the user's connection. At the time of illegal use, it will be able to bear the responsibility on the people and criminal by law. [이용 관련 문의] 070-4337-2467 shpark@wizdome.co.kr is there any way we can restrict the size of the encrypted value using AES-256-GCM mode(I am using 32bit length master key)? Any help is highly appreciated. Thanks! This comment has been minimized. Sign in to view. Copy link Quote reply Owner Author AndiDittrich commented Oct 24, 2019. the size of the. On these appliances, AES-NI is enabled by default. AES-NI is also supported on Open Servers. Make sure that Gaia OS is running in 64-bit mode. Note: Refer to sk110549 - vSEC Virtual Edition (VE) Gateway support for AES-NI on VMware ESX. Affected encryption algorithms include: AES-CBC (128-bit and 256-bit) AES-GCM (128-bit and 256-bit), which shows the most significant improvement - with AES-NI. Give our aes-256-gcm encrypt/decrypt tool a try! aes-256-gcm encrypt or aes-256-gcm decrypt any string with just one mouse click

블록 암호 운용 방식 - 위키백과, 우리 모두의 백과사

AES-GCM (Galois/Counter mode of operation), proposed by McGrew and Viega [1], [2] and standardized by NIST [3] in 2007, is one of the most widely used AEs in practical applications such as SSL/TLS. Galois Counter Mode Advanced Encryption Standard GCM-AES. Overview News Downloads Bugtracker. Project maintainers. Ahmad, Tariq; Details. Name: gcm-aes Created: Oct 14, 2010 Updated: Oct 16, 2010 SVN Updated: Oct 16, 2010 SVN: Browse Latest version: download (might take a bit to start...) Statistics: View Bugs: 0 reported / 0 solved

Creative Mode - Official ARK: Survival Evolved Wik

[GCM] National Institute of Standards and Technology, Recommendation for Block Cipher Modes of Operation: Galois/Counter Mode (GCM) for Confidentiality and Authentication, SP 800-38D, November 2007. 7.2 The configured cipher suites should be the same between MACsec peers. MACsec utilizes the Galois/Counter Mode Advanced Encryption Standard (GCM-AES). The default cipher suite used for MACsec is GCM-AES-128, with a maximum key length of 128 bits. MACsec also supports GCM-AES-256, with a maximum key length of 256 bits GCM(Galois/Counter Mode) In cryptography, Galois/Counter Mode (GCM) is the mode of operation for symmetric key cryptographic block ciphers widely adopted thanks to its performance. An operation is the authenticated encryption algorithm designed to provide both data integrity and confidentiality Download Limit Exceeded You have exceeded your daily download allowance

Modern modes of operation for symmetric block ciphers — PyCryptodome 3

AES-GCM was first introduced in 11.5.0, and it is only available for TLSv1.2 connections. GCM stands for Galois/Counter Mode, a more advanced mode of operation than CBC. In GCM the blocks are not chained together. GCM runs in an Authenticated Encryption with Associated Data (AEAD) mode which eliminates the separate per Description. The SSH server is configured to support Cipher Block Chaining (CBC) encryption. This may allow an attacker to recover the plaintext message from the ciphertext. Note that this plugin only checks for the options of the SSH server and does not check for vulnerable software versions

Galois/Counter Mode Crypto Wiki Fando

Network Working Group E. Rescorla Request for Comments: 5289 RTFM, Inc. Category: Informational August 2008 TLS Elliptic Curve Cipher Suites with SHA-256/384 and AES Galois Counter Mode (GCM) Status of This Memo This memo provides information for the Internet community The decrypt() method of the SubtleCrypto interface decrypts some encrypted data. It takes as arguments a key to decrypt with, some optional extra parameters, and the data to decrypt (also known as ciphertext). It returns a Promise which will be fulfilled with the decrypted data (also known as plaintext) The GCM/CCM mode of the SM4 algorithm is defined in the rfc 8998 specification, and the test case data also comes from rfc 8998. Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>--- crypto/testmgr.c | 29 +++++ crypto/testmgr.h | 148 +++++ 2 files changed, 177 insertions(+

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AES-NI GCM Crypto Poll Mode Driver — dpdk 0.11 documentation. 3. AES-NI GCM Crypto Poll Mode Driver ¶. The AES-NI GCM PMD ( librte_pmd_aesni_gcm) provides poll mode crypto driver support for utilizing Intel ISA-L crypto library, which provides operation acceleration through the AES-NI instruction sets for AES-GCM authenticated cipher algorithm All: --cipher ALG - Data channel cipher.Will be deprecated.. In OpenVPN 2.5 --cipher does not have a default ALG. In OpenVPN up to 2.4 the default ALG is BF-CBC.. 2.4: --ncp-disable - Disable NCP - Deprecated. In this Wiki cipher negotiation comes in four flavours: Full negotiation: Both server and client support NCP ; Partial negotiation: Only the client supports NCP (Known as Poor man's NCP This page describes forward mode, the default mode of operation, where the files are stored encrypted on disk and the mounted filesystem provides a plaintext view. Master Key Storage. The master key is used to perform content and file name encryption. It is stored in gocryptfs.conf, encrypted with AES-256-GCM using the Key Encryption Key (KEK) GCM( Galois/Counter Mode ) GCM中的G就是指GMAC,C就是指CTR。 GCM可以提供对消息的加密和完整性校验,另外,它还可以提供附加消息的完整性校验。在实际应用场景中,有些信息是我们不需要保密,但信息的接收者需要确认它的真实性的,例如源IP,源端口,目的IP,IV,等等