I do not think the EVP_MD_CTX_reset() is that much useful anymore. It is not required before another call to EVP_DigestInit_ex. In theory it could be useful if you're using the MD context for DigestSign/DigestVerify operation and then you'd like to use it for a pure Digest operation. But I do not think anybody would reuse the MD context in such sequence of operations. Tomas Mraz On Sat, 2023-02-11 at 16:12 -0800, Hal Murray wrote: > I'm expecting the answer to be "not in your use case" but I'm fishing > for > something I might have overlooked. > > The man page says: > EVP_MD_CTX_reset() > Resets the digest context ctx. This can be used to reuse > an > already existing context. > > I have a subroutine that does: > EVP_DigestInit_ex > EVP_DigestUpdate > EVP_DigestFinal_ex > > That code is reusing a ctx. The init often gets a new digest. It > works > without the reset. > > What does "reuse" mean? When would EVP_MD_CTX_reset() be necessary? > > -- Tomáš Mráz, OpenSSL
