From 35338b41058b0bcebb137eb098e785f171d0476f Mon Sep 17 00:00:00 2001
From: Artem Boldariev <artem@boldariev.com>
Date: Mon, 9 May 2022 19:08:29 +0300
Subject: [PATCH] Add SSL_SESSION_is_resumable() implementation shim

This commit adds SSL_SESSION_is_resumable() implementation if it is
missing.
---
 configure.ac           | 1 +
 lib/isc/openssl_shim.c | 8 ++++++++
 lib/isc/openssl_shim.h | 5 +++++
 3 files changed, 14 insertions(+)

diff --git a/configure.ac b/configure.ac
index 84108c9820..7b284ef6da 100644
--- a/configure.ac
+++ b/configure.ac
@@ -667,6 +667,7 @@ AC_CHECK_FUNCS([SSL_CTX_up_ref])
 AC_CHECK_FUNCS([SSL_read_ex SSL_peek_ex SSL_write_ex])
 AC_CHECK_FUNCS([SSL_CTX_set1_cert_store X509_STORE_up_ref])
 AC_CHECK_FUNCS([SSL_CTX_up_ref])
+AC_CHECK_FUNCS([SSL_SESSION_is_resumable])
 
 #
 # Check for algorithm support in OpenSSL
diff --git a/lib/isc/openssl_shim.c b/lib/isc/openssl_shim.c
index c39ba8c682..040fc68fbb 100644
--- a/lib/isc/openssl_shim.c
+++ b/lib/isc/openssl_shim.c
@@ -196,3 +196,11 @@ SSL_CTX_up_ref(SSL_CTX *ctx) {
 	return (CRYPTO_add(&ctx->references, 1, CRYPTO_LOCK_SSL_CTX) > 0);
 }
 #endif /* !HAVE_SSL_CTX_UP_REF */
+
+#if !HAVE_SSL_SESSION_IS_RESUMABLE
+int
+SSL_SESSION_is_resumable(const SSL_SESSION *sess) {
+	return (!sess->not_resumable &&
+		(sess->session_id_length > 0 || sess->tlsext_ticklen > 0));
+}
+#endif /* HAVE_SSL_SESSION_IS_RESUMABLE */
diff --git a/lib/isc/openssl_shim.h b/lib/isc/openssl_shim.h
index b2916e20a9..6b3a30b288 100644
--- a/lib/isc/openssl_shim.h
+++ b/lib/isc/openssl_shim.h
@@ -135,3 +135,8 @@ SSL_CTX_set1_cert_store(SSL_CTX *ctx, X509_STORE *store);
 int
 SSL_CTX_up_ref(SSL_CTX *store);
 #endif /* !HAVE_SSL_CTX_UP_REF */
+
+#if !HAVE_SSL_SESSION_IS_RESUMABLE
+int
+SSL_SESSION_is_resumable(const SSL_SESSION *s);
+#endif /* HAVE_SSL_SESSION_IS_RESUMABLE */