Struct rustls::crypto::CipherSuiteCommon

pub struct CipherSuiteCommon {
    pub suite: CipherSuite,
    pub hash_provider: &'static dyn Hash,
    pub confidentiality_limit: u64,
    pub integrity_limit: u64,
}

Common state for cipher suites (both for TLS 1.2 and TLS 1.3)

Fields

suite: CipherSuite

The TLS enumeration naming this cipher suite.

hash_provider: &'static dyn Hash

Which hash function the suite uses.

confidentiality_limit: u64

Number of messages that can be safely encrypted with a single key of this type

Once a MessageEncrypter produced for this suite has encrypted more than confidentiality_limit messages, an attacker gains an advantage in distinguishing it from an ideal pseudorandom permutation (PRP).

This is to be set on the assumption that messages are maximally sized – at least 2 ** 14 bytes for TCP-TLS and 2 ** 16 for QUIC.

integrity_limit: u64

Number of messages that can be safely decrypted with a single key of this type

Once a MessageDecrypter produced for this suite has failed to decrypt integrity_limit messages, an attacker gains an advantage in forging messages.

This is not relevant for TLS over TCP (which is implemented in this crate) because a single failed decryption is fatal to the connection. However, this quantity is used by QUIC.