Some clear guidelines for the legacy algs.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15860)

diff --git a/doc/man7/migration_guide.pod b/doc/man7/migration_guide.pod
index 82c7ffcc432fd3d6ac14c6471f5420de689acc82..6d281472c97cf0179ce3a6de25315574cf476f71 100644 (file)
--- a/doc/man7/migration_guide.pod
+++ b/doc/man7/migration_guide.pod
@@ -60,6 +60,12 @@ There is however a dedicated C<install_fips> make target, which serves the
 special purpose of installing only the FIPS provider into an existing
 OpenSSL installation.
 
+Not all algorithms may be available for the application at a particular moment.
+If the application code uses any digest or cipher algorithm via the EVP interface,
+the application should verify the result of the L<EVP_EncryptInit(3)>,
+L<EVP_EncryptInit_ex(3)>, and L<EVP_DigestInit(3)> functions. In case when
+the requested algorithm is not available, these functions will fail.
+
 See also L</Legacy Algorithms> for information on the legacy provider.
 
 See also L</Completing the installation of the FIPS Module> and