From 03fbef9c241d9a04e2baa45aa2b436bdae8ba67e Mon Sep 17 00:00:00 2001 From: Dmitry Belyavskiy Date: Sun, 1 Dec 2019 11:53:14 +0300 Subject: [PATCH] Difference between EVP_CipherInit and EVP_CipherInit_ex Fixes #10455 Reviewed-by: Paul Dale Reviewed-by: Tomas Mraz (Merged from https://github.com/openssl/openssl/pull/10550) --- doc/man3/EVP_EncryptInit.pod | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/doc/man3/EVP_EncryptInit.pod b/doc/man3/EVP_EncryptInit.pod index 6b068617b0..aaf9975c4c 100644 --- a/doc/man3/EVP_EncryptInit.pod +++ b/doc/man3/EVP_EncryptInit.pod @@ -492,6 +492,15 @@ EVP_EncryptFinal_ex(), EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex() and EVP_CipherFinal_ex() because they can reuse an existing context without allocating and freeing it up on each call. +There are some differences between functions EVP_CipherInit() and +EVP_CipherInit_ex(), significant in some circumstances. EVP_CipherInit() fills +the passed context object with zeros. As a consequence, EVP_CipherInit() does +not allow step-by-step initialization of the ctx when the I and I are +passed in separate calls. It also means that the flags set for the CTX are +removed, and it is especially important for the +B flag treated specially in +EVP_CipherInit_ex(). + EVP_get_cipherbynid(), and EVP_get_cipherbyobj() are implemented as macros. =head1 BUGS -- 2.25.1