[ruby/openssl] require OpenSSL >= 1.0.2 and LibreSSL >= 3.1

Clean up old version guards in preparation for the upcoming OpenSSL 3.0
support.

OpenSSL 1.0.1 reached its EOL on 2016-12-31. At that time, we decided
to keep 1.0.1 support because many major Linux distributions were still
shipped with 1.0.1. Now, nearly 4 years later, most Linux distributions
are reaching their EOL and it should be safe to assume nobody uses them
anymore. Major ones that were using 1.0.1:

 - Ubuntu 14.04 is EOL since 2019-04-30
 - RHEL 6 will reach EOL on 2020-11-30

LibreSSL 3.0 and older versions are no longer supported by the LibreSSL
team as of October 2020.

Note that OpenSSL 1.0.2 also reached EOL on 2019-12-31 and 1.1.0 also
did on 2018-08-31.

https://github.com/ruby/openssl/commit/c055938f4b

1 files changed, 0 insertions, 37 deletions

diff --git a/ext/openssl/openssl_missing.c b/ext/openssl/openssl_missing.c
index 010c158dc1..8b93cba6d4 100644
--- a/ext/openssl/openssl_missing.c
+++ b/ext/openssl/openssl_missing.c
@@ -17,43 +17,6 @@
 
 #include "openssl_missing.h"
 
-/* added in 1.0.2 */
-#if !defined(OPENSSL_NO_EC)
-#if !defined(HAVE_EC_CURVE_NIST2NID)
-static struct {
-    const char *name;
-    int nid;
-} nist_curves[] = {
-    {"B-163", NID_sect163r2},
-    {"B-233", NID_sect233r1},
-    {"B-283", NID_sect283r1},
-    {"B-409", NID_sect409r1},
-    {"B-571", NID_sect571r1},
-    {"K-163", NID_sect163k1},
-    {"K-233", NID_sect233k1},
-    {"K-283", NID_sect283k1},
-    {"K-409", NID_sect409k1},
-    {"K-571", NID_sect571k1},
-    {"P-192", NID_X9_62_prime192v1},
-    {"P-224", NID_secp224r1},
-    {"P-256", NID_X9_62_prime256v1},
-    {"P-384", NID_secp384r1},
-    {"P-521", NID_secp521r1}
-};
-
-int
-ossl_EC_curve_nist2nid(const char *name)
-{
-    size_t i;
-    for (i = 0; i < (sizeof(nist_curves) / sizeof(nist_curves[0])); i++) {
-	if (!strcmp(nist_curves[i].name, name))
-	    return nist_curves[i].nid;
-    }
-    return NID_undef;
-}
-#endif
-#endif
-
 /*** added in 1.1.0 ***/
 #if !defined(HAVE_X509_CRL_GET0_SIGNATURE)
 void