Documentation
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Overview ¶
Package rsa implements RSA encryption as specified in PKCS #1 and RFC 8017.
RSA is a single, fundamental operation that is used in this package to implement either public-key encryption or public-key signatures.
The original specification for encryption and signatures with RSA is PKCS #1 and the terms "RSA encryption" and "RSA signatures" by default refer to PKCS #1 version 1.5. However, that specification has flaws and new designs should use version 2, usually called by just OAEP and PSS, where possible.
Two sets of interfaces are included in this package. When a more abstract interface isn't necessary, there are functions for encrypting/decrypting with v1.5/OAEP and signing/verifying with v1.5/PSS. If one needs to abstract over the public key primitive, the PrivateKey type implements the Decrypter and Signer interfaces from the crypto package.
Operations in this package are implemented using constant-time algorithms, except for [GenerateKey], [PrivateKey.Precompute], and [PrivateKey.Validate]. Every other operation only leaks the bit size of the involved values, which all depend on the selected key size.
Index ¶
Constants ¶
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Variables ¶
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Functions ¶
func EncryptPKCS1v15 ¶
EncryptPKCS1v15 encrypts the given message with RSA and the padding scheme from PKCS #1 v1.5. The message must be no longer than the length of the public modulus minus 11 bytes.
The random parameter is used as a source of entropy to ensure that encrypting the same message twice doesn't result in the same ciphertext. Most applications should use crypto/rand.Reader as random. Note that the returned ciphertext does not depend deterministically on the bytes read from random, and may change between calls and/or between versions.
WARNING: use of this function to encrypt plaintexts other than session keys is dangerous. Use RSA OAEP in new protocols.
func VerifyPKCS1v15 ¶
VerifyPKCS1v15 verifies an RSA PKCS #1 v1.5 signature. hashed is the result of hashing the input message using the given hash function and sig is the signature. A valid signature is indicated by returning a nil error. If hash is zero then hashed is used directly. This isn't advisable except for interoperability.
Types ¶
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Source Files