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To answer your questions: Using serpent-twofish-aes only makes sense if you believe there is a cryptographic break which will work for one but not all three. Using this idea, if one is broken, the others will continue to protect your information. In order to be practical to decrypt your data assuming a model where the attacker has no known ...


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If the module you're using is FIPS 140-2 validated I recommend you read the publicly available Security Policy. This as well as the product documentation should tell you if you are able to export the private key. The Security Policy is available here: http://csrc.nist.gov/groups/STM/cmvp/validation.html It could be that the module does not support AES key ...


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From what you described, it's not secure at all, for a bunch of reasons. The top two being: You're downloading data over HTTP. Even if AES provides confidentiality, it doesn't provide message authenticity or integrity. You're using hard-coded keys. Pulling those out would be trivial, even with obfuscation. This would mean I could MitM your traffic and send ...


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Thales nShield HSMs allow wrapping of a private key. It is possible to set a key ACL it to allow wrapping of it by any key, and in that case "authorization" consists of only being able to load the private key. When using the Thales PKCS#11 library, keys can be set to CKA_EXTRACTABLE=true to allow C_WrapKey, and in that case wrapping will be allowed by any ...


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FIPS 140-2 does not explicitly forbid key export; what it says is that the module shall prevent unauthorized disclosure; it furthermore states that when a private key is exported from a module, it shall be done with encryption. The important word is "unauthorized": simply encrypting with an AES key is not enough; that key must also be such that it is known ...


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Encryption works on sequences of bits. It can encrypt anything that can be represented as bits. It cannot encrypt anything that has not been converted to bits. Fortunately, anything in a computer, by definition, is, at some level, a sequence of bits. Conversion of floating-point integers into bits and back is a common thing to do, subject to some standards ...


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The security of this scheme depends on exactly what the attacker is able to read. Remember the embedded device is performing decryption, so it clearly has all the parts needed to do so (encrypted data, key, and algorithm) If the attacker has any sort of debug connection to the system (e.g. JTAG) -- Game Over (immediately and effortlessly). Attacker can ...


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You don't specify a use case for this, so it's difficult to understand the limitations, and if this is "secure". You didn't mention using an HMAC, but I'm assuming you're aware of the need for one under certain applications. You want to use AES-256 over AES-128, but don't specify why. AES-256 requires 14 rounds, vs only 10 for AES-128, so AES-128 is ...


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If you are using a simple passphrase-based approach, then your encryption is at most as secure as your passphrase. And even if you are using a long passphrase, your encryption is at most as secure as the key derivation function used to get from the passphrase to the actual key. Openssl uses a simple MD5 hash to generate the key, which has two drawbacks: It ...


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Generating rainbow tables is never the best way to attack a single instance. Rainbow tables are precomputed tables: you do a lot of computations in advance, under the hope that you will be able to apply these computations to several attack instances. Precomputed tables (rainbow or not rainbow, this does not change anything here) all follow the same pattern: ...


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Updated Answer: According to: https://groups.google.com/forum/#!msg/mailing.openssl.users/hGggWxfrZbA/unBfGlsfXyoJ the gcm support is currently broken in v1.0.1f (what Ubuntu currently uses). There should be patches out for Version v1.0.1.g which then should have a workable GCM mode. However, currently I would just stick with the CBC mode, as for key ...


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The cost of encrypting data with AES is proportional to the size of such data. If you send 2 terabytes of data through your SSL connection, you will encrypt 2 terabytes of data and the cost of such encryption will completely dwarf anything that happens with RSA. On the other hand, if you send a single byte through your connection, the costs related to AES ...


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You can look up available algorithms by running gpg --version, An example output might include: Cipher: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH, CAMELLIA128, CAMELLIA192, CAMELLIA256 Start the edit menu using gpg --edit-key [key-id] (replacing [key-id] with your key id, and you might have to use gpg.exe again as described above). ...



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