encryption-asymmetric

问题 I'm learning about RSA encryption and I have understood how to encrypt a single letter. I have problems understanding how does RSA work while encrypting a sentence. For eg: Single letter encryption: A Encryption= A^e (mod n) But in a sentence. For eg: Sentence encryption: Hello World Does each word get encrypted or does the sentences as a whole get encrypted? 回答1: Neither. In practice RSA is almost always coupled with a symmetric cipher such as AES to encrypt larger ciphertext. RSA in itself

问题 Hi this is the same question, that was asked two years ago: Java/JCE: Decrypting “long” message encrypted with RSA I had a large byte array and rsa keypair, initiated by value 1024. Using rsa encryption and the specified size of the key is strong requirement, I can't change it. So I can't use symmetric encryption with asymetric encryption symmetric key. I can't use any other keys. I had a byte array and need ciphered byte array to be returned. I wonder if there is any ready tool, that can

问题 I am making a web service that will store public and private keys for each record in a database table. The keys are made using Java, but I am unsure weather to create a keystore or place the keys inside fields in the databbase directly. What option would you recommend and what are the benefits of each method? 回答1: If you use a keystore, you'll be using a database that has been designed to keep encrypted items, such as keys and certificates. Wherever possible, you shouldn't try and re-invent

问题 I'm trying to communicate using RSA preshared keys and, ideally, without involving truststore shenanigans The setup is basically like this: There's an applet on client side and a servlet on server side (duh :) ) The applet has servlet's RSA public key (Spub) hardcoded. The servlet has it's own RSA private key (Spriv) hardcoded. They applet generates a random AES 256 key (session key), encrypts it with servlet's public key (which it has hardcoded), connects to the servlet over a TCP socket and

问题 Why do I need to use separate public key pairs for signing and encryption and not use the same key pair with RSA for example? Is there any security problem with using the same key? 回答1: The reason for using separate key pairs for signing and encryption is to spread the risk: If someone recovers the private encryption key, he/she can decrypt documents that were encrypted using the public encryption key but can’t use it to also sign documents and vice versa. Another reason could be a legal

问题 Why do I need to use separate public key pairs for signing and encryption and not use the same key pair with RSA for example? Is there any security problem with using the same key? 回答1: The reason for using separate key pairs for signing and encryption is to spread the risk: If someone recovers the private encryption key, he/she can decrypt documents that were encrypted using the public encryption key but can’t use it to also sign documents and vice versa. Another reason could be a legal

问题 What's the difference between a keystore and a truststore? 回答1: A keystore contains private keys, and the certificates with their corresponding public keys. A truststore contains certificates from other parties that you expect to communicate with, or from Certificate Authorities that you trust to identify other parties. 回答2: A keystore contains private keys. You only need this if you are a server, or if the server requires client authentication. A truststore contains CA certificates to trust.

问题 I need to load the following RSA public key from a file for use with the RSACryptoServiceProvider class. How can I do this? -----BEGIN PUBLIC KEY----- XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/syEKqEkMtQL0+d XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX+izR KbGMRtur2TYklnyVkjeeHfAggo8vWQmWesnOG55vQYHbOOFoJbk0EkwEr5R/PbKm byXPPN8zwnS5/XXXXXXXXXXXX -----END PUBLIC KEY----- This code works with my pub key: http://www.jensign.com/opensslkey/ Here is the code I am using

问题 I am working on a project that would like to be able to use certificates or keys as a method of authentication for SNMPv3. We are using the java library SNMP4J. During my research I have found that SNMP uses TLS/DTLS for message encryption and supposedly also for authentication. Source 1 | Source 2 | Source 3 Looking into the little documentation SNMP4J has, I found that it allows the usage of TLS certificates for encrypting traffic. But I am not sure how the authentication is done, if

问题 I have generated master pub/priv key pairs from 24 word mnemonics for Alice. master_private_key='9f74f4534cbdf01a1f925e20108d86045bd96849af9c94534a10ef2a26ff133b', master_public_key="0308de0952b00ebc83a41830794534ae912b86d3718832a36ce98c256ab5bfdc4e" mnemonic='flash city relief spirit federal own metal history great hello toy volcano same subway loan bleak rapid swamp pigeon secret pyramid spoon famous blouse', Similarly I have repeated the same process to generate keys for Bob. Now I want to