From 6f3aae256d62cfcc48c07cc0ead5080b070f371b Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Thu, 18 Apr 2019 10:54:58 +0100 Subject: [PATCH] Clarify the documentation on the use of ChaCha20 Reviewed-by: Tim Hudson (Merged from https://github.com/openssl/openssl/pull/8780) --- doc/man3/EVP_chacha20.pod | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/doc/man3/EVP_chacha20.pod b/doc/man3/EVP_chacha20.pod index 7b014c2675..5218ee215f 100644 --- a/doc/man3/EVP_chacha20.pod +++ b/doc/man3/EVP_chacha20.pod @@ -21,7 +21,15 @@ The ChaCha20 stream cipher for EVP. =item EVP_chacha20() -The ChaCha20 stream cipher. The key length is 256 bits, the IV is 96 bits long. +The ChaCha20 stream cipher. The key length is 256 bits, the IV is 128 bits long. +The first 32 bits consists of a counter in little-endian order followed by a 96 +bit nonce. For example a nonce of: + +000000000000000000000002 + +With an initial counter of 42 (2a in hex) would be expressed as: + +2a000000000000000000000000000002 =item EVP_chacha20_poly1305() -- 2.25.1