diff --git a/lib/dns/opensslrsa_link.c b/lib/dns/opensslrsa_link.c
index 26c1182805..2e03a2f022 100644
--- a/lib/dns/opensslrsa_link.c
+++ b/lib/dns/opensslrsa_link.c
@@ -1562,14 +1562,251 @@ static dst_func_t opensslrsa_functions = {
 	NULL, /*%< restore */
 };
 
+/*
+ * An RSA public key with 2048 bits
+ */
+static const unsigned char e_bytes[] = "\x01\x00\x01";
+static const unsigned char n_bytes[] =
+	"\xc3\x90\x07\xbe\xf1\x85\xfc\x1a\x43\xb1\xa5\x15\xce\x71\x34\xfc\xc1"
+	"\x87\x27\x28\x38\xa4\xcf\x7c\x1a\x82\xa8\xdc\x04\x14\xd0\x3f\xb4\xfe"
+	"\x20\x4a\xdd\xd9\x0d\xd7\xcd\x61\x8c\xbd\x61\xa8\x10\xb5\x63\x1c\x29"
+	"\x15\xcb\x41\xee\x43\x91\x7f\xeb\xa5\x2c\xab\x81\x75\x0d\xa3\x3d\xe4"
+	"\xc8\x49\xb9\xca\x5a\x55\xa1\xbb\x09\xd1\xfb\xcd\xa2\xd2\x12\xa4\x85"
+	"\xdf\xa5\x65\xc9\x27\x2d\x8b\xd7\x8b\xfe\x6d\xc4\xd1\xd9\x83\x1c\x91"
+	"\x7d\x3d\xd0\xa4\xcd\xe1\xe7\xb9\x7a\x11\x38\xf9\x8b\x3c\xec\x30\xb6"
+	"\x36\xb9\x92\x64\x81\x56\x3c\xbc\xf9\x49\xfb\xba\x82\xb7\xa0\xfa\x65"
+	"\x79\x83\xb9\x4c\xa7\xfd\x53\x0b\x5a\xe4\xde\xf9\xfc\x38\x7e\xb5\x2c"
+	"\xa0\xc3\xb2\xfc\x7c\x38\xb0\x63\x50\xaf\x00\xaa\xb2\xad\x49\x54\x1e"
+	"\x8b\x11\x88\x9b\x6e\xae\x3b\x23\xa3\xdd\x53\x51\x80\x7a\x0b\x91\x4e"
+	"\x6d\x32\x01\xbd\x17\x81\x12\x64\x9f\x84\xae\x76\x53\x1a\x63\xa0\xda"
+	"\xcc\x45\x04\x72\xb0\xa7\xfb\xfa\x02\x39\x53\xc1\x83\x1f\x88\x54\x47"
+	"\x88\x63\x20\x71\x5d\xe2\xaa\x7c\x53\x39\x5e\x35\x25\xee\xe6\x5c\x15"
+	"\x5e\x14\xbe\x99\xde\x25\x19\xe7\x13\xdb\xce\xa3\xd3\x6c\x5c\xbb\x0e"
+	"\x6b";
+
+static const unsigned char sha1_sig[] =
+	"\x69\x99\x89\x28\xe0\x38\x34\x91\x29\xb6\xac\x4b\xe9\x51\xbd\xbe\xc8"
+	"\x1a\x2d\xb6\xca\x99\xa3\x9f\x6a\x8b\x94\x5a\x51\x37\xd5\x8d\xae\x87"
+	"\xed\xbc\x8e\xb8\xa3\x60\x6b\xf6\xe6\x72\xfc\x26\x2a\x39\x2b\xfe\x88"
+	"\x1a\xa9\xd1\x93\xc7\xb9\xf8\xb6\x45\xa1\xf9\xa1\x56\x78\x7b\x00\xec"
+	"\x33\x83\xd4\x93\x25\x48\xb3\x50\x09\xd0\xbc\x7f\xac\x67\xc7\xa2\x7f"
+	"\xfc\xf6\x5a\xef\xf8\x5a\xad\x52\x74\xf5\x71\x34\xd9\x3d\x33\x8b\x4d"
+	"\x99\x64\x7e\x14\x59\xbe\xdf\x26\x8a\x67\x96\x6c\x1f\x79\x85\x10\x0d"
+	"\x7f\xd6\xa4\xba\x57\x41\x03\x71\x4e\x8c\x17\xd5\xc4\xfb\x4a\xbe\x66"
+	"\x45\x15\x45\x0c\x02\xe0\x10\xe1\xbb\x33\x8d\x90\x34\x3c\x94\xa4\x4c"
+	"\x7c\xd0\x5e\x90\x76\x80\x59\xb2\xfa\x54\xbf\xa9\x86\xb8\x84\x1e\x28"
+	"\x48\x60\x2f\x9e\xa4\xbc\xd4\x9c\x20\x27\x16\xac\x33\xcb\xcf\xab\x93"
+	"\x7a\x3b\x74\xa0\x18\x92\xa1\x4f\xfc\x52\x19\xee\x7a\x13\x73\xba\x36"
+	"\xaf\x78\x5d\xb6\x1f\x96\x76\x15\x73\xee\x04\xa8\x70\x27\xf7\xe7\xfa"
+	"\xe8\xf6\xc8\x5f\x4a\x81\x56\x0a\x94\xf3\xc6\x98\xd2\x93\xc4\x0b\x49"
+	"\x6b\x44\xd3\x73\xa2\xe3\xef\x5d\x9e\x68\xac\xa7\x42\xb1\xbb\x65\xbe"
+	"\x59";
+
+static const unsigned char sha256_sig[] =
+	"\x0f\x8c\xdb\xe6\xb6\x21\xc8\xc5\x28\x76\x7d\xf6\xf2\x3b\x78\x47\x77"
+	"\x03\x34\xc5\x5e\xc0\xda\x42\x41\xc0\x0f\x97\xd3\xd0\x53\xa1\xd6\x87"
+	"\xe4\x16\x29\x9a\xa5\x59\xf4\x01\xad\xc9\x04\xe7\x61\xe2\xcb\x79\x73"
+	"\xce\xe0\xa6\x85\xe5\x10\x8c\x4b\xc5\x68\x3b\x96\x42\x3f\x56\xb3\x6d"
+	"\x89\xc4\xff\x72\x36\xf2\x3f\xed\xe9\xb8\xe3\xae\xab\x3c\xb7\xaa\xf7"
+	"\x1f\x8f\x26\x6b\xee\xc1\xac\x72\x89\x23\x8b\x7a\xd7\x8c\x84\xf3\xf5"
+	"\x97\xa8\x8d\xd3\xef\xb2\x5e\x06\x04\x21\xdd\x28\xa2\x28\x83\x68\x9b"
+	"\xac\x34\xdd\x36\x33\xda\xdd\xa4\x59\xc7\x5a\x4d\xf3\x83\x06\xd5\xc0"
+	"\x0d\x1f\x4f\x47\x2f\x9f\xcc\xc2\x0d\x21\x1e\x82\xb9\x3d\xf3\xa4\x1a"
+	"\xa6\xd8\x0e\x72\x1d\x71\x17\x1c\x54\xad\x37\x3e\xa4\x0e\x70\x86\x53"
+	"\xfb\x40\xad\xb9\x14\xf8\x8d\x93\xbb\xd7\xe7\x31\xce\xe0\x98\xda\x27"
+	"\x1c\x18\x8e\xd8\x85\xcb\xa7\xb1\x18\xac\x8c\xa8\x9d\xa9\xe2\xf6\x30"
+	"\x95\xa4\x81\xf4\x1c\xa0\x31\xd5\xc7\x9d\x28\x33\xee\x7f\x08\x4f\xcb"
+	"\xd1\x14\x17\xdf\xd0\x88\x78\x47\x29\xaf\x6c\xb2\x62\xa6\x30\x87\x29"
+	"\xaa\x80\x19\x7d\x2f\x05\xe3\x7e\x23\x73\x88\x08\xcc\xbd\x50\x46\x09"
+	"\x2a";
+
+static const unsigned char sha512_sig[] =
+	"\x15\xda\x87\x87\x1f\x76\x08\xd3\x9d\x3a\xb9\xd2\x6a\x0e\x3b\x7d\xdd"
+	"\xec\x7d\xc4\x6d\x26\xf5\x04\xd3\x76\xc7\x83\xc4\x81\x69\x35\xe9\x47"
+	"\xbf\x49\xd1\xc0\xf9\x01\x4e\x0a\x34\x5b\xd0\xec\x6e\xe2\x2e\xe9\x2d"
+	"\x00\xfd\xe0\xa0\x28\x54\x53\x19\x49\x6d\xd2\x58\xb9\x47\xfa\x45\xad"
+	"\xd2\x1d\x52\xac\x80\xcb\xfc\x91\x97\x84\x58\x5f\xab\x21\x62\x60\x79"
+	"\xb8\x8a\x83\xe1\xf1\xcb\x05\x4c\x92\x56\x62\xd9\xbf\xa7\x81\x34\x23"
+	"\xdf\xd7\xa7\xc4\xdf\xde\x96\x00\x57\x4b\x78\x85\xb9\x3b\xdd\x3f\x98"
+	"\x88\x59\x1d\x48\xcf\x5a\xa8\xb7\x2a\x8b\x77\x93\x8e\x38\x3a\x0c\xa7"
+	"\x8a\x5f\xe6\x9f\xcb\xf0\x9a\x6b\xb6\x91\x04\x8b\x69\x6a\x37\xee\xa2"
+	"\xad\x5f\x31\x20\x96\xd6\x51\x80\xbf\x62\x48\xb8\xe4\x94\x10\x86\x4e"
+	"\xf2\x22\x1e\xa4\xd5\x54\xfe\xe1\x35\x49\xaf\xf8\x62\xfc\x11\xeb\xf7"
+	"\x3d\xd5\x5e\xaf\x11\xbd\x3d\xa9\x3a\x9f\x7f\xe8\xb4\x0d\xa2\xbb\x1c"
+	"\xbd\x4c\xed\x9e\x81\xb1\xec\xd3\xea\xaa\x03\xe3\x14\xdf\x8c\xb3\x78"
+	"\x85\x5e\x87\xad\xec\x41\x1a\xa9\x4f\xd2\xe6\xc6\xbe\xfa\xb8\x10\xea"
+	"\x74\x25\x36\x0c\x23\xe2\x24\xb7\x21\xb7\x0d\xaf\xf6\xb4\x31\xf5\x75"
+	"\xf1";
+
+static isc_result_t
+check_algorithm(unsigned char algorithm) {
+	BIGNUM *n = NULL, *e = NULL;
+	EVP_MD_CTX *evp_md_ctx = EVP_MD_CTX_create();
+	EVP_PKEY *pkey = NULL;
+	const EVP_MD *type = NULL;
+	const unsigned char *sig = NULL;
+	int status;
+	isc_result_t ret = ISC_R_SUCCESS;
+	size_t len;
+#if OPENSSL_VERSION_NUMBER < 0x30000000L
+	RSA *rsa = NULL;
+#else
+	OSSL_PARAM *params = NULL;
+	OSSL_PARAM_BLD *bld = NULL;
+	EVP_PKEY_CTX *ctx = NULL;
+#endif
+
+	if (evp_md_ctx == NULL) {
+		DST_RET(ISC_R_NOMEMORY);
+	}
+
+	switch (algorithm) {
+	case DST_ALG_RSASHA1:
+	case DST_ALG_NSEC3RSASHA1:
+		type = EVP_sha1(); /* SHA1 + RSA */
+		sig = sha1_sig;
+		len = sizeof(sha1_sig) - 1;
+		break;
+	case DST_ALG_RSASHA256:
+		type = EVP_sha256(); /* SHA256 + RSA */
+		sig = sha256_sig;
+		len = sizeof(sha256_sig) - 1;
+		break;
+	case DST_ALG_RSASHA512:
+		type = EVP_sha512();
+		sig = sha512_sig;
+		len = sizeof(sha512_sig) - 1;
+		break;
+	default:
+		DST_RET(ISC_R_NOTIMPLEMENTED);
+	}
+
+	if (type == NULL) {
+		DST_RET(ISC_R_NOTIMPLEMENTED);
+	}
+
+	/*
+	 * Construct pkey.
+	 */
+	e = BN_bin2bn(e_bytes, sizeof(e_bytes) - 1, NULL);
+	n = BN_bin2bn(n_bytes, sizeof(n_bytes) - 1, NULL);
+	if (e == NULL || n == NULL) {
+		DST_RET(ISC_R_NOMEMORY);
+	}
+
+#if OPENSSL_VERSION_NUMBER < 0x30000000L
+	rsa = RSA_new();
+	if (rsa == NULL) {
+		DST_RET(dst__openssl_toresult2("RSA_new",
+					       DST_R_OPENSSLFAILURE));
+	}
+	status = RSA_set0_key(rsa, n, e, NULL);
+	if (status != 1) {
+		DST_RET(dst__openssl_toresult2("RSA_set0_key",
+					       DST_R_OPENSSLFAILURE));
+	}
+
+	/* These are now managed by OpenSSL. */
+	n = NULL;
+	e = NULL;
+
+	pkey = EVP_PKEY_new();
+	if (pkey == NULL) {
+		DST_RET(dst__openssl_toresult2("EVP_PKEY_new",
+					       DST_R_OPENSSLFAILURE));
+	}
+	status = EVP_PKEY_set1_RSA(pkey, rsa);
+	if (status != 1) {
+		DST_RET(dst__openssl_toresult2("EVP_PKEY_set1_RSA",
+					       DST_R_OPENSSLFAILURE));
+	}
+#else
+	bld = OSSL_PARAM_BLD_new();
+	if (bld == NULL) {
+		DST_RET(dst__openssl_toresult2("OSSL_PARAM_BLD_new",
+					       DST_R_OPENSSLFAILURE));
+	}
+	if (OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_N, n) != 1 ||
+	    OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_RSA_E, e) != 1)
+	{
+		DST_RET(dst__openssl_toresult2("OSSL_PARAM_BLD_push_BN",
+					       DST_R_OPENSSLFAILURE));
+	}
+	params = OSSL_PARAM_BLD_to_param(bld);
+	if (params == NULL) {
+		DST_RET(dst__openssl_toresult2("OSSL_PARAM_BLD_to_param",
+					       DST_R_OPENSSLFAILURE));
+	}
+	ctx = EVP_PKEY_CTX_new_from_name(NULL, "RSA", NULL);
+	if (ctx == NULL) {
+		DST_RET(dst__openssl_toresult2("EVP_PKEY_CTX_new_from_name",
+					       DST_R_OPENSSLFAILURE));
+	}
+	status = EVP_PKEY_fromdata_init(ctx);
+	if (status != 1) {
+		DST_RET(dst__openssl_toresult2("EVP_PKEY_fromdata_init",
+					       DST_R_OPENSSLFAILURE));
+	}
+	status = EVP_PKEY_fromdata(ctx, &pkey, EVP_PKEY_PUBLIC_KEY, params);
+	if (status != 1 || pkey == NULL) {
+		DST_RET(dst__openssl_toresult2("EVP_PKEY_fromdata",
+					       DST_R_OPENSSLFAILURE));
+	}
+#endif
+
+	/*
+	 * Check that we can verify the signature.
+	 */
+	if (EVP_DigestInit_ex(evp_md_ctx, type, NULL) != 1 ||
+	    EVP_DigestUpdate(evp_md_ctx, "test", 4) != 1 ||
+	    EVP_VerifyFinal(evp_md_ctx, sig, len, pkey) != 1)
+	{
+		DST_RET(ISC_R_NOTIMPLEMENTED);
+	}
+
+err:
+	BN_free(e);
+	BN_free(n);
+#if OPENSSL_VERSION_NUMBER < 0x30000000L
+	if (rsa != NULL) {
+		RSA_free(rsa);
+	}
+#else
+	if (bld != NULL) {
+		OSSL_PARAM_BLD_free(bld);
+	}
+	if (ctx != NULL) {
+		EVP_PKEY_CTX_free(ctx);
+	}
+	if (params != NULL) {
+		OSSL_PARAM_free(params);
+	}
+#endif
+	if (pkey != NULL) {
+		EVP_PKEY_free(pkey);
+	}
+	if (evp_md_ctx != NULL) {
+		EVP_MD_CTX_destroy(evp_md_ctx);
+	}
+	ERR_clear_error();
+	return (ret);
+}
+
 isc_result_t
 dst__opensslrsa_init(dst_func_t **funcp, unsigned char algorithm) {
+	isc_result_t result;
+
 	REQUIRE(funcp != NULL);
 
-	UNUSED(algorithm);
+	result = check_algorithm(algorithm);
 
-	if (*funcp == NULL) {
-		*funcp = &opensslrsa_functions;
+	if (result == ISC_R_SUCCESS) {
+		if (*funcp == NULL) {
+			*funcp = &opensslrsa_functions;
+		}
+	} else if (result == ISC_R_NOTIMPLEMENTED) {
+		result = ISC_R_SUCCESS;
 	}
-	return (ISC_R_SUCCESS);
+
+	return (result);
 }
diff --git a/util/gen-rsa-sha-vectors.c b/util/gen-rsa-sha-vectors.c
new file mode 100644
index 0000000000..7f76036b84
--- /dev/null
+++ b/util/gen-rsa-sha-vectors.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#include <stdio.h>
+
+#include <openssl/bn.h>
+#include <openssl/core_names.h>
+#include <openssl/err.h>
+#include <openssl/evp.h>
+#include <openssl/objects.h>
+#include <openssl/opensslv.h>
+#include <openssl/param_build.h>
+#include <openssl/rsa.h>
+
+/*
+ *  Generate test vectors for lib/dns/opensslrsa_link.c as:
+ *
+ *  Fedora 33 doesn't support RSASHA1 in future mode.  There is no easy
+ *  check for this other than by attempting to perform a verification
+ *  using known good signatures.  We don't attempt to sign with RSASHA1
+ *  as that would not work in FIPS mode.  RSASHA1 is verify only.
+ *
+ *  The test vectors were generated using OpenSSL 3.0 and
+ *  util/gen-rsa-sha-vectors.c.  Rerunning will generate a new set of
+ *  test vectors as the private key is not preserved.
+ *
+ *  e.g.
+ *          cc util/gen-rsa-sha-vectors.c -I /opt/local/include \
+ *                  -L /opt/local/lib -lcrypto
+ */
+
+int
+main() {
+	BIGNUM *e = BN_new();
+	BIGNUM *n = BN_new();
+	EVP_PKEY_CTX *ctx = EVP_PKEY_CTX_new_from_name(NULL, "RSA", NULL);
+	EVP_PKEY *pkey = NULL;
+	unsigned char buf[512];
+	size_t bytes;
+	EVP_MD_CTX *evp_md_ctx = EVP_MD_CTX_create();
+	unsigned int siglen = sizeof(buf);
+
+	if (e == NULL || n == NULL || ctx == NULL || evp_md_ctx == NULL) {
+		return (1);
+	}
+
+	BN_set_bit(e, 0);
+	BN_set_bit(e, 16);
+
+	if (EVP_PKEY_keygen_init(ctx) != 1 ||
+	    EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, 2048) != 1 ||
+	    EVP_PKEY_CTX_set1_rsa_keygen_pubexp(ctx, e) != 1 ||
+	    EVP_PKEY_keygen(ctx, &pkey) != 1 || pkey == NULL)
+	{
+		return (1);
+	}
+
+	EVP_PKEY_get_bn_param(pkey, OSSL_PKEY_PARAM_RSA_N, &n);
+	if (n == NULL) {
+		return (1);
+	}
+
+	bytes = BN_num_bytes(e);
+	BN_bn2bin(e, buf);
+	printf("unsigned char e_bytes[] = \"");
+	for (size_t i = 0; i < bytes; i++) {
+		printf("\\x%02x", buf[i]);
+	}
+	printf("\";\n");
+
+	bytes = BN_num_bytes(n);
+	BN_bn2bin(n, buf);
+	printf("unsigned char n_bytes[] = \"");
+	for (size_t i = 0; i < bytes; i++) {
+		printf("\\x%02x", buf[i]);
+	}
+	printf("\";\n\n");
+
+	if (EVP_DigestInit_ex(evp_md_ctx, EVP_sha1(), NULL) != 1 ||
+	    EVP_DigestUpdate(evp_md_ctx, "test", 4) != 1 ||
+	    EVP_SignFinal(evp_md_ctx, buf, &siglen, pkey) != 1)
+	{
+		return (1);
+	}
+	bytes = siglen;
+	printf("unsigned char sha1_sig[] = \"");
+	for (size_t i = 0; i < bytes; i++) {
+		printf("\\x%02x", buf[i]);
+	}
+	printf("\";\n\n");
+
+	if (EVP_DigestInit_ex(evp_md_ctx, EVP_sha256(), NULL) != 1 ||
+	    EVP_DigestUpdate(evp_md_ctx, "test", 4) != 1 ||
+	    EVP_SignFinal(evp_md_ctx, buf, &siglen, pkey) != 1)
+	{
+		return (1);
+	}
+	bytes = siglen;
+	printf("unsigned char sha256_sig[] = \"");
+	for (size_t i = 0; i < bytes; i++) {
+		printf("\\x%02x", buf[i]);
+	}
+	printf("\";\n\n");
+
+	if (EVP_DigestInit_ex(evp_md_ctx, EVP_sha512(), NULL) != 1 ||
+	    EVP_DigestUpdate(evp_md_ctx, "test", 4) != 1 ||
+	    EVP_SignFinal(evp_md_ctx, buf, &siglen, pkey) != 1)
+	{
+		return (1);
+	}
+	bytes = siglen;
+	printf("unsigned char sha512_sig[] = \"");
+	for (size_t i = 0; i < bytes; i++) {
+		printf("\\x%02x", buf[i]);
+	}
+	printf("\";\n\n");
+
+	return (0);
+}