Message For Mac

I started using the Verizon Messages app several years ago to have text messages synced across mutliple devices, only one of which is a Verizon mobile device. I use the Verizon Messages app on my phone, tablet, a Windows computer and a Mac (the latter being the corporate computer). The title of the message is 'Hello' and the -m option provides the actual message text to display. Without the password, no message will be displayed on the remote system. Using growlnotify like. Messages is iMessage for Mac - Apple's replacement for iChat in OS X 10.8. Firstly, note that if you install Messages, it replaces iChat although Apple has assured that iChat services will continue to work. In a further move towards iOS, Messages provides better integration with Messages on iPad, iPhone, and iPod touch running iOS 5.

With Messages for Mac, you can send unlimited messages to any Mac, iPhone, iPad, or iPod touch that uses iMessage, Apple's secure-messaging service. iPhone owners can use it for SMS and MMS messages, too.

Set up iMessage

iMessage is the Apple messaging service you get automatically with your Apple ID.If it's not already set up, you're asked to sign in when you first open the Messages app. Sign in with same Apple ID that you use with Messages on your iPhone and other devices. It's usually the same Apple ID that you use for iCloud, the iTunes Store, the App Store, and the account you created when you first set up your Mac.

Have a conversation

  1. Click at the top of the Messages window.
  2. Address your message by typing the recipient's name, email address, or phone number. Or click and choose a recipient. If they're in your Contacts app, Messages finds them as you type. To start a group conversation, just add more recipients.
  3. Type your message in the field at the bottom of the window, then press Return to send it.
    • To include emoji, click.
    • To include an image or other file, just drag or paste it into the message field. Or use Continuity Camera to capture a photo or scan directly from your iPhone or iPad camera.
    • To include an audio recording, clickand record your message.
  4. After starting a conversation, click Details in the corner of the window to take other actions, including:
    • Choose not to be disturbed by notifications about this conversation.
    • Use FaceTime to start an audio call or video call .
    • Share a screen .
    • See the recipient's location—if they're sharing their location with you.
    • Review all of the photos and files that were exchanged in the conversation.
    • Add a group name, add members to a group, or leave a group. If the group has four or more members, you can remove members: Control-click the member's name, then choose Remove from Conversation.

With macOS Sierra or later, you can also use Siri to send, read, and reply to Messages:

  • ”Send a message to Susan and Johnny saying I'll be late' or ”Tell Johnny Appleseed the show is about to start” or ”Text a message to 408 555 1212.”
  • ”Read the last message from Brian Park” or ”Read my new messages.”
  • ”Reply that's great news” or ”Tell him I'll be there in 10 minutes.”

Add a Tapback to a message

macOS Sierra introduces Tapback to the Mac. A Tapback is a quick response that expresses what you think about a message, such as that you like it or think it's funny. In the image above, the heart next to ”See you then!' is a Tapback. Here's how to do it:

  1. Control-click a message bubble to open a shortcut menu.
  2. Choose Tapback from the menu.
  3. Click a Tapback to add it to the message bubble.

Your Tapback is visible to everyone in the conversation who is using iMessage with macOS Sierra or later or iOS 10 or later. Other iMessage users see 'Liked' or 'Laughed at' or 'Emphasized,' for example, followed by the text of that message.

iPhone, iPad, and iPod touch also have Tapback, as well as other message effects available only on those devices. Most such affects look the same on your Mac when you receive them. Others appear as a description of the effect, such as ”(sent with Loud Effect).”

Send text messages to anyone from your Mac

If you have an iPhone with a text messaging plan, learn how to set up text message forwarding so you can send and receive SMS and MMS messages from your Mac.

Delete a message or conversation

When you permanently delete a message or conversation, you can't get it back. So make sure that you save important information from your messages.

To delete a message:

  1. Open a message conversation.
  2. Control-click the blank area of a message bubble that you want to delete.
  3. Choose Delete.
  4. Click Delete.

To delete a conversation:

  1. Control-click a conversation.
  2. Choose Delete Conversation.
  3. Click Delete.
MessageInsta message for mac

Learn more

  • To learn more about Messages, choose Messages Help from the Help menu in Messages.
  • If you get an error when trying to sign in to iMessage, learn what to do.

FaceTime is not available in all countries or regions.

ProMessage machine for phone

In cryptography, a message authentication code (MAC), sometimes known as a tag, is a short piece of information used to authenticate a message—in other words, to confirm that the message came from the stated sender (its authenticity) and has not been changed. The MAC value protects both a message's data integrity as well as its authenticity, by allowing verifiers (who also possess the secret key) to detect any changes to the message content.

Definitions[edit]

Informally, a message authentication code system consists of three algorithms:

Apple messages for mac
  • A key generation algorithm selects a key from the key space uniformly at random.
  • A signing algorithm efficiently returns a tag given the key and the message.
  • A verifying algorithm efficiently verifies the authenticity of the message given the key and the tag. That is, return accepted when the message and tag are not tampered with or forged, and otherwise return rejected.

For a secure unforgeable message authentication code, it should be computationally infeasible to compute a valid tag of the given message without knowledge of the key, even if for the worst case, we assume the adversary can forge the tag of any message except the given one.[1]

Formally, a message authentication code (MAC) system is a triple of efficient[2] algorithms (G, S, V) satisfying:

  • G (key-generator) gives the key k on input 1n, where n is the security parameter.
  • S (signing) outputs a tag t on the key k and the input string x.
  • V (verifying) outputs accepted or rejected on inputs: the key k, the string x and the tag t.

S and V must satisfy the following:

Pr [ kG(1n), V( k, x, S(k, x) ) = accepted ] = 1.[3]

A MAC is unforgeable if for every efficient adversary A

Pr [ kG(1n), (x, t) ← AS(k, · )(1n), x ∉ Query(AS(k, · ), 1n), V(k, x, t) = accepted] < negl(n),

where AS(k, · ) denotes that A has access to the oracle S(k, · ), and Query(AS(k, · ), 1n) denotes the set of the queries on S made by A, which knows n. Clearly we require that any adversary cannot directly query the string x on S, since otherwise a valid tag can be easily obtained by that adversary.[4]

Security[edit]

While MAC functions are similar to cryptographic hash functions, they possess different security requirements. To be considered secure, a MAC function must resist existential forgery under chosen-plaintext attacks. This means that even if an attacker has access to an oracle which possesses the secret key and generates MACs for messages of the attacker's choosing, the attacker cannot guess the MAC for other messages (which were not used to query the oracle) without performing infeasible amounts of computation.

MACs differ from digital signatures as MAC values are both generated and verified using the same secret key. This implies that the sender and receiver of a message must agree on the same key before initiating communications, as is the case with symmetric encryption. For the same reason, MACs do not provide the property of non-repudiation offered by signatures specifically in the case of a network-wide shared secret key: any user who can verify a MAC is also capable of generating MACs for other messages. In contrast, a digital signature is generated using the private key of a key pair, which is public-key cryptography[2]. Since this private key is only accessible to its holder, a digital signature proves that a document was signed by none other than that holder. Thus, digital signatures do offer non-repudiation. However, non-repudiation can be provided by systems that securely bind key usage information to the MAC key; the same key is in the possession of two people, but one has a copy of the key that can be used for MAC generation while the other has a copy of the key in a hardware security module that only permits MAC verification. This is commonly done in the finance industry.[citation needed]

Message integrity codes[edit]

The term message integrity code (MIC) is frequently substituted for the term MAC, especially in communications,[5] to distinguish it from the use of MAC meaning MAC address (for media access control address). However, some authors[6] use MIC to refer to a message digest, which is different from a MAC – a message digest does not use secret keys. This lack of security means that any message digest intended for use gauging message integrity should be encrypted or otherwise be protected against tampering. Message digest algorithms are created such that a given message will always produce the same message digest assuming the same algorithm is used to generate both. Conversely, MAC algorithms are designed to produce matching MACs only if the same message, secret key and initialization vector are input to the same algorithm. Message digests do not use secret keys and, when taken on their own, are therefore a much less reliable gauge of message integrity than MACs. Because MACs use secret keys, they do not necessarily need to be encrypted to provide the same level of assurance.

RFC 4949 recommends avoiding the term 'message integrity code' (MIC), and instead using 'checksum', 'error detection code', 'hash', 'keyed hash', 'message authentication code', or 'protected checksum'.

Implementation[edit]

MAC algorithms can be constructed from other cryptographic primitives, like cryptographic hash functions (as in the case of HMAC) or from block cipher algorithms (OMAC, CCM, GCM, and PMAC). However many of the fastest MAC algorithms like UMAC-VMAC and Poly1305-AES are constructed based on universal hashing.[7]

Intrinsically keyed hash algorithms such as SipHash are also by definition MACs; they can be even faster than universal-hashing based MACs.[8]

Message Machine For Phone

Additionally, the MAC algorithm can deliberately combine two or more cryptographic primitives, so as to maintain protection even if one of them is later found to be vulnerable. For instance, in Transport Layer Security (TLS), the input data is split in halves that are each processed with a different hashing primitive (SHA-1 and SHA-2) then XORed together to output the MAC.

Standards[edit]

Various standards exist that define MAC algorithms. These include:

  • FIPS PUB 113 Computer Data Authentication,[9] withdrawn in 2002,[10] defines an algorithm based on DES.
  • FIPS PUB 198-1 The Keyed-Hash Message Authentication Code (HMAC)[11]
  • ISO/IEC 9797-1Mechanisms using a block cipher[12]
  • ISO/IEC 9797-2 Mechanisms using a dedicated hash-function[13]
  • ISO/IEC 9797-3 Mechanisms using a universal hash-function[14]
  • ISO/IEC 29192-6 Lightweight cryptography - Message authentication codes[15]

ISO/IEC 9797-1 and -2 define generic models and algorithms that can be used with any block cipher or hash function, and a variety of different parameters. These models and parameters allow more specific algorithms to be defined by nominating the parameters. For example, the FIPS PUB 113 algorithm is functionally equivalent to ISO/IEC 9797-1 MAC algorithm 1 with padding method 1 and a block cipher algorithm of DES.

An example of MAC use[edit]

[16]In this example, the sender of a message runs it through a MAC algorithm to produce a MAC data tag. The message and the MAC tag are then sent to the receiver. The receiver in turn runs the message portion of the transmission through the same MAC algorithm using the same key, producing a second MAC data tag. The receiver then compares the first MAC tag received in the transmission to the second generated MAC tag. If they are identical, the receiver can safely assume that the message was not altered or tampered with during transmission (data integrity).

However, to allow the receiver to be able to detect replay attacks, the message itself must contain data that assures that this same message can only be sent once (e.g. time stamp, sequence number or use of a one-time MAC). Otherwise an attacker could – without even understanding its content – record this message and play it back at a later time, producing the same result as the original sender.

One-time MAC[edit]

Universal hashing and in particular pairwise independent hash functions provide a secure message authentication code as long as the key is used at most once. This can be seen as the one-time pad for authentication.[17]

The simplest such pairwise independent hash function is defined by the random key key = (a,b), and the MAC tag for a message m is computed as tag = (am + b) mod p, where p is prime.

More generally, k-independent hashing functions provide a secure message authentication code as long as the key is used less than k times for k-ways independent hashing functions.

See also[edit]

  • Hash-based message authentication code (HMAC)

Notes[edit]

  1. ^The strongest adversary is assumed to have access to the signing algorithm without knowing the key. However, her final forged message must be different from any message she chose to query the signing algorithm before. See Pass's discussions before def 134.2.
  2. ^ abTheoretically, an efficient algorithm runs within probabilistic polynomial time.
  3. ^Pass, def 134.1
  4. ^Pass, def 134.2
  5. ^IEEE 802.11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications(PDF). (2007 revision). IEEE-SA. 12 June 2007. doi:10.1109/IEEESTD.2007.373646. ISBN978-0-7381-5656-9.
  6. ^Fred B Schneider, Hashes and Message Digests, Cornell University
  7. ^'VMAC: Message Authentication Code using Universal Hashing'. CFRG Working Group. CFRG Working Group. Retrieved 16 March 2010.
  8. ^Jean-Philippe Aumasson & Daniel J. Bernstein (2012-09-18). 'SipHash: a fast short-input PRF'(PDF).
  9. ^'FIPS PUB 113 Computer Data Authentication'. Archived from the original on 2011-09-27. Retrieved 2010-10-10.
  10. ^'Federal Information Processing Standards Publications, Withdrawn FIPS Listed by Number'. Archived from the original on 2010-08-01. Retrieved 2010-10-10.
  11. ^The Keyed-Hash Message Authentication Code (HMAC)
  12. ^ISO/IEC 9797-1 Information technology — Security techniques — Message Authentication Codes (MACs) — Part 1: Mechanisms using a block cipher
  13. ^ISO/IEC 9797-2 Information technology — Security techniques — Message Authentication Codes (MACs) — Part 2: Mechanisms using a dedicated hash-function
  14. ^ISO/IEC 9797-3 Information technology — Security techniques — Message Authentication Codes (MACs) — Part 3: Mechanisms using a universal hash-function
  15. ^ISO/IEC 29192-6 Information technology — Lightweight cryptography — Part 6: Message authentication codes (MACs)
  16. ^'Mac Security Overview', Mac® Security Bible, Wiley Publishing, Inc., 2011-11-01, pp. 1–26, doi:10.1002/9781118257739.ch1, ISBN9781118257739
  17. ^Simmons, Gustavus (1985). 'Authentication theory/coding theory'. Advances in Cryptology: Proceedings of CRYPTO 84. Berlin: Springer. pp. 411–431. ISBN00000000 Check |isbn= value: length (help).

References[edit]

Message For Macbeth

  • Goldreich, Oded (2001), Foundations of cryptography I: Basic Tools, Cambridge: Cambridge University Press, ISBN978-0-511-54689-1
  • Goldreich, Oded (2004), Foundations of cryptography II: Basic Applications (1. publ. ed.), Cambridge [u.a.]: Cambridge Univ. Press, ISBN978-0-521-83084-3
  • Pass, Rafael, A Course in Cryptography(PDF), retrieved 31 December 2015[1]

External links[edit]

  1. ^11-12-20C8

Instagram Direct Message For Mac

Retrieved from 'https://en.wikipedia.org/w/index.php?title=Message_authentication_code&oldid=983323091'