Another Challenge of Hash Functions

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TLS Server Name Indication Extension and Unrecognized_name

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Heavy Pond, Jianfengling National Forest Park, Ledong, Hainan, China It's getting hot that some TLS/HTTPS server failed with "unrecognized_name". For example, the Adobe AIR 3 Code Signing Certificate Problem , the ADT handshake alert , and the jarsigner issue with timestamp.geotrust.com , etc. This entry will discussion some background of the "unrecognized_name" alert, and the TLS Server Name Indication (SNI) extension. Background "Unrecognized_name" is an error alert, define by RFC4366 .  In section 4 of RFC4366 : - "unrecognized_name": this alert is sent by servers that receive a server_name extension request, but do not recognize the server name. This message MAY be fatal. And in section 3.1 of of RFC4366 : If the server understood the client hello extension but does not recognize the server name, it SHOULD send an "unrecognized_name" alert (which MAY be fatal). From above sections, we see that "unrecognized...
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NIST Security Strength Time Frames

Security Strength Time Frames of NIST SP 800-57 Part 1 Security Strength 80 112 128 192 256 applying processing applying processing through 2010 acceptable acceptable acceptable acceptable acceptable acceptable acceptable 2011 through2013 deprecated legacy use acceptable acceptable acceptable acceptable acceptable 2014 through 2030 disallowed legacy use acceptable acceptable acceptable acceptable acceptable 2031 and Beyond disallowed legacy use disallowed legacy use acceptable acceptable acceptable Symmetric Algorithms 2TDEA 3TDEA AES-128 AES-192 AES-256 FFC (e.g., DSA, D-H) L = 1024 N = 160 L = 2048 N = 224 L = 3072 N = 256 L = 7680 N = 384 L = 15360 N = 512 IFC (e.g., RSA) k = 1024 k = 2048 k = 3072 k = 7680 k = 15360 ECC (e.g.,ECDSA) f = 160-223 f = 224-255 f = 256-383 f = 384-511 f = 512+ Digital Signatures and hash-only applications SHA-1, SHA-224, SHA-256, SHA-384, SHA-5...
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JEP 114: TLS SNI Extension - Virtual Servers Dispatcher

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The implementation of  JEP 114  (TLS Server Name Indication (SNI) Extension) had  integrated into JDK 8  at October, 2012. In  the previous blog entries , we talked about the behavior changes in JSSE, and a few typical user cases . Let's look at a special user case, how to design a virtual server dispatcher in Java. Please refer to javax.net.ssl package of  JDK 8 APIs  for the detailed specification. Prepare the ClientHello Parser Applications need to implementation their own APIs to parser the client hello message from a plaintext socket. Suppose that an application design the following API to do the work, SSLCapabilities and SSLExplorer. SSLCapabilities is defined to show the SSL/TLS security capabilities during handshaking, SSLCapabilities can be retrieved by exploring the network data of an SSL/TLS connection via SSLExplorer.explore(ByteBuffer). /** * Encapsulates the security capabilities * of an SSL/TLS connection. * * Th...
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