OCB - Revision history

Jwalton: Added ciphers available for the mode.

2016-06-30T19:27:25Z

Added ciphers available for the mode.

Jwalton: Fixed URL reference.

2013-11-26T02:55:24Z

Fixed URL reference.

Jwalton: Fixed spelling; added link to test vectors.

2013-11-26T02:38:29Z

Fixed spelling; added link to test vectors.

Matt: Grammar corrections

2013-11-25T21:15:22Z

Grammar corrections

Jwalton: Added info on the mode and original paper

2013-11-25T21:06:44Z

Added info on the mode and original paper

Matt: Barebones OCB page with link to patent grant file

2013-11-25T20:52:50Z

Barebones OCB page with link to patent grant file

New page

OCB is the Offset Code Book mode.

This mode has been patented by Prof Phil Rogaway and licensed to OpenSSL with the licence grant available [[Media:OCB-patent-grant-OpenSSL.pdf|here]]

← Older revision		Revision as of 19:27, 30 June 2016
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	This mode has been patented by Professor Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogaway's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data]. Test vectors and a reference implementation for interoperability testing can be found at [http://www.cs.ucdavis.edu/~rogaway/ocb/news/ OCB News and Code].		This mode has been patented by Professor Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogaway's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data]. Test vectors and a reference implementation for interoperability testing can be found at [http://www.cs.ucdavis.edu/~rogaway/ocb/news/ OCB News and Code].
		+
		+	Please see [[EVP_Symmetric_Encryption_and_Decryption\|EVP Symmetric Encryption and Decryption]] or [[EVP_Authenticated_Encryption_and_Decryption\|EVP Authenticated Encryption and Decryption]]. The choice of <tt>EVP_CIPHER</tt> includes:
		+
		+	<pre>$ grep "EVP_.*_ocb" include/openssl/evp.h
		+	const EVP_CIPHER *EVP_aes_128_ocb(void);
		+	const EVP_CIPHER *EVP_aes_192_ocb(void);
		+	const EVP_CIPHER *EVP_aes_256_ocb(void);</pre>

← Older revision		Revision as of 02:55, 26 November 2013
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	OCB is the Offset Code Book mode. The mode provides an efficient form of authenticated encryption with additional data, which is commonly referred to as an AEAD scheme. OCB mode is efficient because blocks of data are visited once to generate the cipher text and create the authentication tag. In contrast, modes like CCM, EAX and GCM visit the block of data twice due to US patent encumbrances - once to encrypt the data and once to create the authentication tag. For more information, see Dr. David Wagner's comparison of AEAD schemes at [http://www.cryptopp.com/w/images/9/99/AEAD-Comparison.ppt.zip AEAD Comparison].		OCB is the Offset Code Book mode. The mode provides an efficient form of authenticated encryption with additional data, which is commonly referred to as an AEAD scheme. OCB mode is efficient because blocks of data are visited once to generate the cipher text and create the authentication tag. In contrast, modes like CCM, EAX and GCM visit the block of data twice due to US patent encumbrances - once to encrypt the data and once to create the authentication tag. For more information, see Dr. David Wagner's comparison of AEAD schemes at [http://www.cryptopp.com/w/images/9/99/AEAD-Comparison.ppt.zip AEAD Comparison].

−	This mode has been patented by Professor Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogaway's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data]. Test vectors and a reference implementation for interoperability testing can be found at [http://www.cs.ucdavis.edu/~rogaway/ocb/~~code-1.0.htm~~ OCB ~~1.0~~ and ~~PMAC 1.0:~~ Code].	+	This mode has been patented by Professor Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogaway's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data]. Test vectors and a reference implementation for interoperability testing can be found at [http://www.cs.ucdavis.edu/~rogaway/ocb/news/ OCB News and Code].

← Older revision		Revision as of 02:38, 26 November 2013
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−	OCB is the Offset Code Book mode. The mode provides an efficient form of authenticated encryption with additional data, which is commonly referred to as an AEAD scheme. OCB mode is efficient because blocks of data are visited once to generate the cipher text and create the authentication tag. In contrast, modes like CCM, EAX and GCM visit the block of data twice - once to encrypt the data and once to create the authentication tag ~~due to patent encumbrances~~. For more information, see Dr. David Wagner's comparison of AEAD schemes at [http://www.cryptopp.com/w/images/9/99/AEAD-Comparison.ppt.zip AEAD Comparison].	+	OCB is the Offset Code Book mode. The mode provides an efficient form of authenticated encryption with additional data, which is commonly referred to as an AEAD scheme. OCB mode is efficient because blocks of data are visited once to generate the cipher text and create the authentication tag. In contrast, modes like CCM, EAX and GCM visit the block of data twice due to US patent encumbrances - once to encrypt the data and once to create the authentication tag. For more information, see Dr. David Wagner's comparison of AEAD schemes at [http://www.cryptopp.com/w/images/9/99/AEAD-Comparison.ppt.zip AEAD Comparison].

−	This mode has been patented by ~~Prof~~ Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. ~~Rogawy~~'s paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data].	+	This mode has been patented by Professor Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogaway's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data]. Test vectors and a reference implementation for interoperability testing can be found at [http://www.cs.ucdavis.edu/~rogaway/ocb/code-1.0.htm OCB 1.0 and PMAC 1.0: Code].

← Older revision		Revision as of 21:15, 25 November 2013
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−	OCB is the Offset Code Book mode. The mode provides an efficient form authenticated encryption with additional data, which is commonly referred to an AEAD scheme. OCB mode is efficient because blocks of data are visited once to generate the cipher text and create the authentication tag. In contrast, modes like CCM, EAX and GCM visit the block of data twice - once to encrypt the data and once to create the authentication tag due to patent encumbrances. For more information, see Dr. David Wagner's comparison of AEAD schemes at [http://www.cryptopp.com/w/images/9/99/AEAD-Comparison.ppt.zip AEAD Comparison].	+	OCB is the Offset Code Book mode. The mode provides an efficient form of authenticated encryption with additional data, which is commonly referred to as an AEAD scheme. OCB mode is efficient because blocks of data are visited once to generate the cipher text and create the authentication tag. In contrast, modes like CCM, EAX and GCM visit the block of data twice - once to encrypt the data and once to create the authentication tag due to patent encumbrances. For more information, see Dr. David Wagner's comparison of AEAD schemes at [http://www.cryptopp.com/w/images/9/99/AEAD-Comparison.ppt.zip AEAD Comparison].

	This mode has been patented by Prof Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogawy's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data].		This mode has been patented by Prof Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogawy's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data].

← Older revision		Revision as of 21:06, 25 November 2013
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−	OCB is the Offset Code Book mode.	+	OCB is the Offset Code Book mode. The mode provides an efficient form authenticated encryption with additional data, which is commonly referred to an AEAD scheme. OCB mode is efficient because blocks of data are visited once to generate the cipher text and create the authentication tag. In contrast, modes like CCM, EAX and GCM visit the block of data twice - once to encrypt the data and once to create the authentication tag due to patent encumbrances. For more information, see Dr. David Wagner's comparison of AEAD schemes at [http://www.cryptopp.com/w/images/9/99/AEAD-Comparison.ppt.zip AEAD Comparison].

−	This mode has been patented by Prof Phil Rogaway and licensed to OpenSSL with the ~~licence~~ grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]	+	This mode has been patented by Prof Phil Rogaway and licensed to OpenSSL with the license grant available [[Media:OCB-patent-grant-OpenSSL.pdf\|here]]. Dr. Rogawy's paper can be found at [http://www.cs.ucdavis.edu/~rogaway/papers/ad.pdf Authenticated-Encryption with Associated-Data].