Merge pull request #21170 from keszybz/delibgcryptify

Allow systemd-resolved and systemd-importd to use libgcrypt or libopenssl

.github/workflows/unit_tests.sh

@@ -29,6 +29,8 @@ function info() {
 
 set -ex
 
+MESON_ARGS=(-Dcryptolib=${CRYPTOLIB:-auto})
+
 for phase in "${PHASES[@]}"; do
     case $phase in
         SETUP)

.github/workflows/unit_tests.yml

@@ -22,10 +22,18 @@ jobs:
       fail-fast: false
       matrix:
         run_phase: [GCC, GCC_ASAN_UBSAN, CLANG, CLANG_ASAN_UBSAN]
+        cryptolib: [auto]
+        include:
+          - run_phase: GCC
+            cryptolib: openssl
+          - run_phase: CLANG
+            cryptolib: gcrypt
     steps:
       - name: Repository checkout
         uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579
       - name: Install build dependencies
         run: sudo -E .github/workflows/unit_tests.sh SETUP
-      - name: Build & test (${{ matrix.run_phase }})
+      - name: Build & test (${{ matrix.run_phase }}-${{ matrix.cryptolib }})
         run: sudo -E .github/workflows/unit_tests.sh RUN_${{ matrix.run_phase }}
+        env:
+          CRYPTOLIB: ${{ matrix.cryptolib }}

.packit.yml

@@ -31,6 +31,9 @@ actions:
     # [0] https://github.com/mesonbuild/meson/issues/7360
     # [1] https://github.com/systemd/systemd/pull/18908#issuecomment-792250110
     - 'sed -i "/^CONFIGURE_OPTS=(/a--werror" .packit_rpm/systemd.spec'
+    # FIXME: temporarily disable the deprecated-declarations check to suppress
+    #        OpenSSL 3.0 warnings in Rawhide
+    - 'sed -i "1 i %global optflags %{optflags} -Wno-deprecated-declarations" .packit_rpm/systemd.spec'
 
 jobs:
 - job: copr_build

TODO

@@ -432,11 +432,8 @@ Features:
 * socket units: allow creating a udev monitor socket with ListenDevices= or so,
   with matches, then activate app through that passing socket over
 
-* unify on openssl (as soon as OpenSSL 3.0 is out, and the Debian license
+* unify on openssl:
-  confusion is gone)
-  - port resolved over from libgcrypt (DNSSEC code)
   - port journald + fsprg over from libgcrypt
-  - port importd over from libgcrypt
   - when that's done: kill gnutls support in resolved
 
 * add growvol and makevol options for /etc/crypttab, similar to

meson.build

@@ -1448,21 +1448,25 @@ else
 endif
 conf.set10('HAVE_DBUS', have)
 
-default_dnssec = get_option('default-dnssec')
+# We support one or the other. If gcrypt is available, we assume it's there to
-if skip_deps
+# be used, and use it in preference.
-        default_dnssec = 'no'
+opt = get_option('cryptolib')
+if opt == 'openssl' and conf.get('HAVE_OPENSSL') == 0
+        error('openssl requested as the default cryptolib, but not available')
 endif
-if default_dnssec != 'no' and conf.get('HAVE_GCRYPT') == 0
+conf.set10('PREFER_OPENSSL',
-        message('default-dnssec cannot be set to yes or allow-downgrade when gcrypt is disabled. Setting default-dnssec to no.')
+           opt == 'openssl' or (opt == 'auto' and conf.get('HAVE_OPENSSL') == 1 and conf.get('HAVE_GCRYPT') == 0))
-        default_dnssec = 'no'
+conf.set10('HAVE_OPENSSL_OR_GCRYPT',
-endif
+           conf.get('HAVE_OPENSSL') == 1 or conf.get('HAVE_GCRYPT') == 1)
-conf.set('DEFAULT_DNSSEC_MODE',
+lib_openssl_or_gcrypt = conf.get('PREFER_OPENSSL') == 1 ? libopenssl : libgcrypt
-         'DNSSEC_' + default_dnssec.underscorify().to_upper())
-conf.set_quoted('DEFAULT_DNSSEC_MODE_STR', default_dnssec)
 
 dns_over_tls = get_option('dns-over-tls')
 if dns_over_tls != 'false'
-        if dns_over_tls == 'openssl'
+        if dns_over_tls == 'gnutls' and conf.get('PREFER_OPENSSL') == 1
+                error('Sorry, -Ddns-over-tls=gnutls is not supported when openssl is used as the cryptolib')
+        endif
+
+        if dns_over_tls == 'openssl' or conf.get('PREFER_OPENSSL') == 1
                 have_gnutls = false
         else
                 have_gnutls = (conf.get('HAVE_GNUTLS') == 1 and libgnutls.version().version_compare('>= 3.6.0'))
@@ -1523,12 +1527,24 @@ else
 endif
 conf.set10('ENABLE_REPART', have)
 
+default_dnssec = get_option('default-dnssec')
+if skip_deps
+        default_dnssec = 'no'
+endif
+if default_dnssec != 'no' and conf.get('HAVE_OPENSSL_OR_GCRYPT') == 0
+        message('default-dnssec cannot be set to yes or allow-downgrade openssl and gcrypt are disabled. Setting default-dnssec to no.')
+        default_dnssec = 'no'
+endif
+conf.set('DEFAULT_DNSSEC_MODE',
+         'DNSSEC_' + default_dnssec.underscorify().to_upper())
+conf.set_quoted('DEFAULT_DNSSEC_MODE_STR', default_dnssec)
+
 want_importd = get_option('importd')
 if want_importd != 'false'
         have = (conf.get('HAVE_LIBCURL') == 1 and
+                conf.get('HAVE_OPENSSL_OR_GCRYPT') == 1 and
                 conf.get('HAVE_ZLIB') == 1 and
-                conf.get('HAVE_XZ') == 1 and
+                conf.get('HAVE_XZ') == 1)
-                conf.get('HAVE_GCRYPT') == 1)
         if want_importd == 'true' and not have
                 error('importd support was requested, but dependencies are not available')
         endif
@@ -2139,6 +2155,7 @@ if conf.get('ENABLE_RESOLVE') == 1
                              libbasic_gcrypt,
                              libsystemd_resolve_core],
                 dependencies : [threads,
+                                lib_openssl_or_gcrypt,
                                 libgpg_error,
                                 libm,
                                 libidn],
@@ -2717,10 +2734,10 @@ if conf.get('ENABLE_IMPORTD') == 1
                 link_with : [libshared],
                 dependencies : [versiondep,
                                 libcurl,
+                                lib_openssl_or_gcrypt,
                                 libz,
                                 libbzip2,
-                                libxz,
+                                libxz],
-                                libgcrypt],
                 install_rpath : rootlibexecdir,
                 install : true,
                 install_dir : rootlibexecdir)
@@ -4021,6 +4038,14 @@ else
         found += 'static-libudev(@0@)'.format(static_libudev)
 endif
 
+if conf.get('HAVE_OPENSSL_OR_GCRYPT') == 1 and conf.get('PREFER_OPENSSL') == 1
+        found += 'cryptolib(openssl)'
+elif conf.get('HAVE_OPENSSL_OR_GCRYPT') == 1
+        found += 'cryptolib(gcrypt)'
+else
+        missing += 'cryptolib'
+endif
+
 if conf.get('DNS_OVER_TLS_USE_GNUTLS') == 1
         found += 'DNS-over-TLS(gnutls)'
 elif conf.get('DNS_OVER_TLS_USE_OPENSSL') == 1

meson_options.txt

@@ -380,6 +380,8 @@ option('gnutls', type : 'combo', choices : ['auto', 'true', 'false'],
        description : 'gnutls support')
 option('openssl', type : 'combo', choices : ['auto', 'true', 'false'],
        description : 'openssl support')
+option('cryptolib', type : 'combo', choices : ['auto', 'openssl', 'gcrypt'],
+       description : 'whether to use openssl or gcrypt where both are supported')
 option('p11kit', type : 'combo', choices : ['auto', 'true', 'false'],
        description : 'p11kit support')
 option('libfido2', type : 'combo', choices : ['auto', 'true', 'false'],

src/basic/build.c

@@ -48,7 +48,7 @@ const char* const systemd_features =
         " -SECCOMP"
 #endif
 
-        /* crypto libraries */
+        /* cryptographic libraries */
 
 #if HAVE_GCRYPT
         " +GCRYPT"

src/basic/gcrypt-util.c

@@ -18,6 +18,7 @@ void initialize_libgcrypt(bool secmem) {
         gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);
 }
 
+#  if !PREFER_OPENSSL
 int string_hashsum(const char *s, size_t len, int md_algorithm, char **out) {
         _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL;
         gcry_error_t err;
@@ -47,4 +48,5 @@ int string_hashsum(const char *s, size_t len, int md_algorithm, char **out) {
         *out = enc;
         return 0;
 }
+#  endif
 #endif

src/basic/gcrypt-util.h

@@ -12,23 +12,28 @@
 #include "macro.h"
 
 void initialize_libgcrypt(bool secmem);
-int string_hashsum(const char *s, size_t len, int md_algorithm, char **out);
 
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(gcry_md_hd_t, gcry_md_close, NULL);
 #endif
 
+#if !PREFER_OPENSSL
+#  if HAVE_GCRYPT
+int string_hashsum(const char *s, size_t len, int md_algorithm, char **out);
+#  endif
+
 static inline int string_hashsum_sha224(const char *s, size_t len, char **out) {
-#if HAVE_GCRYPT
+#  if HAVE_GCRYPT
         return string_hashsum(s, len, GCRY_MD_SHA224, out);
-#else
+#  else
         return -EOPNOTSUPP;
-#endif
+#  endif
 }
 
 static inline int string_hashsum_sha256(const char *s, size_t len, char **out) {
-#if HAVE_GCRYPT
+#  if HAVE_GCRYPT
         return string_hashsum(s, len, GCRY_MD_SHA256, out);
-#else
+#  else
         return -EOPNOTSUPP;
-#endif
+#  endif
 }
+#endif

src/import/pull-job.c

@@ -41,8 +41,12 @@ PullJob* pull_job_unref(PullJob *j) {
 
         import_compress_free(&j->compress);
 
-        if (j->checksum_context)
+        if (j->checksum_ctx)
-                gcry_md_close(j->checksum_context);
+#if PREFER_OPENSSL
+                EVP_MD_CTX_free(j->checksum_ctx);
+#else
+                gcry_md_close(j->checksum_ctx);
+#endif
 
         free(j->url);
         free(j->etag);
@@ -102,9 +106,13 @@ static int pull_job_restart(PullJob *j, const char *new_url) {
 
         import_compress_free(&j->compress);
 
-        if (j->checksum_context) {
+        if (j->checksum_ctx) {
-                gcry_md_close(j->checksum_context);
+#if PREFER_OPENSSL
-                j->checksum_context = NULL;
+                EVP_MD_CTX_free(j->checksum_ctx);
+#else
+                gcry_md_close(j->checksum_ctx);
+#endif
+                j->checksum_ctx = NULL;
         }
 
         r = pull_job_begin(j);
@@ -200,16 +208,30 @@ void pull_job_curl_on_finished(CurlGlue *g, CURL *curl, CURLcode result) {
                 goto finish;
         }
 
-        if (j->checksum_context) {
+        if (j->checksum_ctx) {
-                uint8_t *k;
+                unsigned checksum_len;
+#if PREFER_OPENSSL
+                uint8_t k[EVP_MAX_MD_SIZE];
 
-                k = gcry_md_read(j->checksum_context, GCRY_MD_SHA256);
+                r = EVP_DigestFinal_ex(j->checksum_ctx, k, &checksum_len);
+                if (r == 0) {
+                        r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to get checksum.");
+                        goto finish;
+                }
+                assert(checksum_len <= sizeof k);
+#else
+                const uint8_t *k;
+
+                k = gcry_md_read(j->checksum_ctx, GCRY_MD_SHA256);
                 if (!k) {
                         r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to get checksum.");
                         goto finish;
                 }
 
-                j->checksum = hexmem(k, gcry_md_get_algo_dlen(GCRY_MD_SHA256));
+                checksum_len = gcry_md_get_algo_dlen(GCRY_MD_SHA256);
+#endif
+
+                j->checksum = hexmem(k, checksum_len);
                 if (!j->checksum) {
                         r = log_oom();
                         goto finish;
@@ -358,8 +380,16 @@ static int pull_job_write_compressed(PullJob *j, void *p, size_t sz) {
                 return log_error_errno(SYNTHETIC_ERRNO(EFBIG),
                                        "Content length incorrect.");
 
-        if (j->checksum_context)
+        if (j->checksum_ctx) {
-                gcry_md_write(j->checksum_context, p, sz);
+#if PREFER_OPENSSL
+                r = EVP_DigestUpdate(j->checksum_ctx, p, sz);
+                if (r == 0)
+                        return log_error_errno(SYNTHETIC_ERRNO(EIO),
+                                               "Could not hash chunk.");
+#else
+                gcry_md_write(j->checksum_ctx, p, sz);
+#endif
+        }
 
         r = import_uncompress(&j->compress, p, sz, pull_job_write_uncompressed, j);
         if (r < 0)
@@ -392,11 +422,22 @@ static int pull_job_open_disk(PullJob *j) {
         }
 
         if (j->calc_checksum) {
-                initialize_libgcrypt(false);
+#if PREFER_OPENSSL
+                j->checksum_ctx = EVP_MD_CTX_new();
+                if (!j->checksum_ctx)
+                        return log_oom();
 
-                if (gcry_md_open(&j->checksum_context, GCRY_MD_SHA256, 0) != 0)
+                r = EVP_DigestInit_ex(j->checksum_ctx, EVP_sha256(), NULL);
+                if (r == 0)
                         return log_error_errno(SYNTHETIC_ERRNO(EIO),
                                                "Failed to initialize hash context.");
+#else
+                initialize_libgcrypt(false);
+
+                if (gcry_md_open(&j->checksum_ctx, GCRY_MD_SHA256, 0) != 0)
+                        return log_error_errno(SYNTHETIC_ERRNO(EIO),
+                                               "Failed to initialize hash context.");
+#endif
         }
 
         return 0;

src/import/pull-job.h

@@ -1,12 +1,12 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#include <gcrypt.h>
 #include <sys/stat.h>
 
 #include "curl-util.h"
 #include "import-compress.h"
 #include "macro.h"
+#include "openssl-util.h"
 #include "pull-common.h"
 
 typedef struct PullJob PullJob;
@@ -74,7 +74,7 @@ struct PullJob {
         usec_t last_status_usec;
 
         bool calc_checksum;
-        gcry_md_hd_t checksum_context;
+        hash_context_t checksum_ctx;
 
         char *checksum;
         bool sync;

src/partition/repart.c

@@ -12,9 +12,6 @@
 #include <sys/ioctl.h>
 #include <sys/stat.h>
 
-#include <openssl/hmac.h>
-#include <openssl/sha.h>
-
 #include "sd-id128.h"
 
 #include "alloc-util.h"
@@ -38,6 +35,7 @@
 #include "glyph-util.h"
 #include "gpt.h"
 #include "hexdecoct.h"
+#include "hmac.h"
 #include "id128-util.h"
 #include "json.h"
 #include "list.h"
@@ -1519,7 +1517,7 @@ static int fdisk_set_disklabel_id_by_uuid(struct fdisk_context *c, sd_id128_t id
 
 static int derive_uuid(sd_id128_t base, const char *token, sd_id128_t *ret) {
         union {
-                unsigned char md[SHA256_DIGEST_LENGTH];
+                uint8_t md[SHA256_DIGEST_SIZE];
                 sd_id128_t id;
         } result;
 
@@ -1531,11 +1529,7 @@ static int derive_uuid(sd_id128_t base, const char *token, sd_id128_t *ret) {
          * machine ID). We use the machine ID as key (and not as cleartext!) of the HMAC operation since it's
          * the machine ID we don't want to leak. */
 
-        if (!HMAC(EVP_sha256(),
+        hmac_sha256(base.bytes, sizeof(base.bytes), token, strlen(token), result.md);
-                  &base, sizeof(base),
-                  (const unsigned char*) token, strlen(token),
-                  result.md, NULL))
-                return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), "HMAC-SHA256 calculation failed.");
 
         /* Take the first half, mark it as v4 UUID */
         assert_cc(sizeof(result.md) == sizeof(result.id) * 2);
@@ -3067,7 +3061,7 @@ static int partition_acquire_uuid(Context *context, Partition *p, sd_id128_t *re
                 uint64_t counter;
         } _packed_  plaintext = {};
         union {
-                unsigned char md[SHA256_DIGEST_LENGTH];
+                uint8_t md[SHA256_DIGEST_SIZE];
                 sd_id128_t id;
         } result;
 
@@ -3111,11 +3105,10 @@ static int partition_acquire_uuid(Context *context, Partition *p, sd_id128_t *re
         plaintext.type_uuid = p->type_uuid;
         plaintext.counter = htole64(k);
 
-        if (!HMAC(EVP_sha256(),
+        hmac_sha256(context->seed.bytes, sizeof(context->seed.bytes),
-                  &context->seed, sizeof(context->seed),
+                    &plaintext,
-                  (const unsigned char*) &plaintext, k == 0 ? sizeof(sd_id128_t) : sizeof(plaintext),
+                    k == 0 ? sizeof(sd_id128_t) : sizeof(plaintext),
-                  result.md, NULL))
+                    result.md);
-                return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), "SHA256 calculation failed.");
 
         /* Take the first half, mark it as v4 UUID */
         assert_cc(sizeof(result.md) == sizeof(result.id) * 2);

src/resolve/meson.build

@@ -176,14 +176,16 @@ tests += [
         [['src/resolve/test-resolve-tables.c'],
          [libsystemd_resolve_core,
           libshared],
-         [libgcrypt,
+         [lib_openssl_or_gcrypt,
+          libgcrypt,
           libgpg_error,
           libm]],
 
         [['src/resolve/test-dns-packet.c'],
          [libsystemd_resolve_core,
           libshared],
-         [libgcrypt,
+         [lib_openssl_or_gcrypt,
+          libgcrypt,
           libgpg_error,
           libm]],
 
@@ -192,28 +194,33 @@ tests += [
           'src/resolve/resolved-etc-hosts.h'],
          [libsystemd_resolve_core,
           libshared],
-         [libgcrypt,
+         [lib_openssl_or_gcrypt,
+          libgcrypt,
           libgpg_error,
           libm]],
 
         [['src/resolve/test-resolved-packet.c'],
          [libsystemd_resolve_core,
           libshared],
-         [libgcrypt,
+         [lib_openssl_or_gcrypt,
+          libgcrypt,
           libgpg_error,
           libm]],
 
         [['src/resolve/test-dnssec.c'],
          [libsystemd_resolve_core,
           libshared],
-         [libgcrypt,
+         [lib_openssl_or_gcrypt,
+          libgcrypt,
           libgpg_error,
-          libm]],
+          libm],
+         [], 'HAVE_OPENSSL_OR_GCRYPT'],
 
         [['src/resolve/test-dnssec-complex.c'],
          [libsystemd_resolve_core,
           libshared],
-         [libgcrypt,
+         [lib_openssl_or_gcrypt,
+          libgcrypt,
           libgpg_error,
           libm],
          [], '', 'manual'],
@@ -223,7 +230,8 @@ fuzzers += [
         [['src/resolve/fuzz-dns-packet.c'],
          [libsystemd_resolve_core,
           libshared],
-         [libgcrypt,
+         [lib_openssl_or_gcrypt,
+          libgcrypt,
           libgpg_error,
           libm]],
 ]

src/resolve/resolvectl.c

@@ -23,6 +23,7 @@
 #include "main-func.h"
 #include "missing_network.h"
 #include "netlink-util.h"
+#include "openssl-util.h"
 #include "pager.h"
 #include "parse-argument.h"
 #include "parse-util.h"

src/resolve/resolved-conf.c

@@ -498,14 +498,14 @@ int manager_parse_config_file(Manager *m) {
                         return r;
         }
 
-#if ! HAVE_GCRYPT
+#if !HAVE_OPENSSL_OR_GCRYPT
         if (m->dnssec_mode != DNSSEC_NO) {
-                log_warning("DNSSEC option cannot be enabled or set to allow-downgrade when systemd-resolved is built without gcrypt support. Turning off DNSSEC support.");
+                log_warning("DNSSEC option cannot be enabled or set to allow-downgrade when systemd-resolved is built without a cryptographic library. Turning off DNSSEC support.");
                 m->dnssec_mode = DNSSEC_NO;
         }
 #endif
 
-#if ! ENABLE_DNS_OVER_TLS
+#if !ENABLE_DNS_OVER_TLS
         if (m->dns_over_tls_mode != DNS_OVER_TLS_NO) {
                 log_warning("DNS-over-TLS option cannot be enabled or set to opportunistic when systemd-resolved is built without DNS-over-TLS support. Turning off DNS-over-TLS support.");
                 m->dns_over_tls_mode = DNS_OVER_TLS_NO;

src/resolve/resolved-dns-dnssec.c

@@ -7,6 +7,7 @@
 #include "gcrypt-util.h"
 #include "hexdecoct.h"
 #include "memory-util.h"
+#include "openssl-util.h"
 #include "resolved-dns-dnssec.h"
 #include "resolved-dns-packet.h"
 #include "sort-util.h"
@@ -58,7 +59,7 @@ uint16_t dnssec_keytag(DnsResourceRecord *dnskey, bool mask_revoke) {
         return sum & UINT32_C(0xFFFF);
 }
 
-#if HAVE_GCRYPT
+#if HAVE_OPENSSL_OR_GCRYPT
 
 static int rr_compare(DnsResourceRecord * const *a, DnsResourceRecord * const *b) {
         const DnsResourceRecord *x = *a, *y = *b;
@@ -82,12 +83,67 @@ static int rr_compare(DnsResourceRecord * const *a, DnsResourceRecord * const *b
 }
 
 static int dnssec_rsa_verify_raw(
-                const char *hash_algorithm,
+                hash_algorithm_t hash_algorithm,
                 const void *signature, size_t signature_size,
                 const void *data, size_t data_size,
                 const void *exponent, size_t exponent_size,
                 const void *modulus, size_t modulus_size) {
 
+#if PREFER_OPENSSL
+        _cleanup_(RSA_freep) RSA *rpubkey = NULL;
+        _cleanup_(EVP_PKEY_freep) EVP_PKEY *epubkey = NULL;
+        _cleanup_(EVP_PKEY_CTX_freep) EVP_PKEY_CTX *ctx = NULL;
+        _cleanup_(BN_freep) BIGNUM *e = NULL, *m = NULL;
+        int r;
+
+        assert(hash_algorithm);
+
+        e = BN_bin2bn(exponent, exponent_size, NULL);
+        if (!e)
+                return -EIO;
+
+        m = BN_bin2bn(modulus, modulus_size, NULL);
+        if (!m)
+                return -EIO;
+
+        rpubkey = RSA_new();
+        if (!rpubkey)
+                return -ENOMEM;
+
+        if (RSA_set0_key(rpubkey, m, e, NULL) <= 0)
+                return -EIO;
+        e = m = NULL;
+
+        assert((size_t) RSA_size(rpubkey) == signature_size);
+
+        epubkey = EVP_PKEY_new();
+        if (!epubkey)
+                return -ENOMEM;
+
+        if (EVP_PKEY_assign_RSA(epubkey, RSAPublicKey_dup(rpubkey)) <= 0)
+                return -EIO;
+
+        ctx = EVP_PKEY_CTX_new(epubkey, NULL);
+        if (!ctx)
+                return -ENOMEM;
+
+        if (EVP_PKEY_verify_init(ctx) <= 0)
+                return -EIO;
+
+        if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) <= 0)
+                return -EIO;
+
+        if (EVP_PKEY_CTX_set_signature_md(ctx, hash_algorithm) <= 0)
+                return -EIO;
+
+        r = EVP_PKEY_verify(ctx, signature, signature_size, data, data_size);
+        if (r < 0)
+                return log_debug_errno(SYNTHETIC_ERRNO(EIO),
+                                       "Signature verification failed: 0x%lx", ERR_get_error());
+
+        return r;
+
+#else
         gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL;
         gcry_mpi_t n = NULL, e = NULL, s = NULL;
         gcry_error_t ge;
@@ -147,10 +203,10 @@ static int dnssec_rsa_verify_raw(
         ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp);
         if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE)
                 r = 0;
-        else if (ge != 0) {
+        else if (ge != 0)
-                log_debug("RSA signature check failed: %s", gpg_strerror(ge));
+                r = log_debug_errno(SYNTHETIC_ERRNO(EIO),
-                r = -EIO;
+                                    "RSA signature check failed: %s", gpg_strerror(ge));
-        } else
+        else
                 r = 1;
 
 finish:
@@ -169,10 +225,11 @@ finish:
                 gcry_sexp_release(data_sexp);
 
         return r;
+#endif
 }
 
 static int dnssec_rsa_verify(
-                const char *hash_algorithm,
+                hash_algorithm_t hash_algorithm,
                 const void *hash, size_t hash_size,
                 DnsResourceRecord *rrsig,
                 DnsResourceRecord *dnskey) {
@@ -228,13 +285,78 @@ static int dnssec_rsa_verify(
 }
 
 static int dnssec_ecdsa_verify_raw(
-                const char *hash_algorithm,
+                hash_algorithm_t hash_algorithm,
-                const char *curve,
+                elliptic_curve_t curve,
                 const void *signature_r, size_t signature_r_size,
                 const void *signature_s, size_t signature_s_size,
                 const void *data, size_t data_size,
                 const void *key, size_t key_size) {
 
+#if PREFER_OPENSSL
+        _cleanup_(EC_GROUP_freep) EC_GROUP *ec_group = NULL;
+        _cleanup_(EC_POINT_freep) EC_POINT *p = NULL;
+        _cleanup_(EC_KEY_freep) EC_KEY *eckey = NULL;
+        _cleanup_(BN_CTX_freep) BN_CTX *bctx = NULL;
+        _cleanup_(BN_freep) BIGNUM *r = NULL, *s = NULL;
+        _cleanup_(ECDSA_SIG_freep) ECDSA_SIG *sig = NULL;
+        int k;
+
+        assert(hash_algorithm);
+
+        ec_group = EC_GROUP_new_by_curve_name(curve);
+        if (!ec_group)
+                return -ENOMEM;
+
+        p = EC_POINT_new(ec_group);
+        if (!p)
+                return -ENOMEM;
+
+        bctx = BN_CTX_new();
+        if (!bctx)
+                return -ENOMEM;
+
+        if (EC_POINT_oct2point(ec_group, p, key, key_size, bctx) <= 0)
+                return -EIO;
+
+        eckey = EC_KEY_new();
+        if (!eckey)
+                return -ENOMEM;
+
+        if (EC_KEY_set_group(eckey, ec_group) <= 0)
+                return -EIO;
+
+        if (EC_KEY_set_public_key(eckey, p) <= 0)
+                return log_debug_errno(SYNTHETIC_ERRNO(EIO),
+                                       "EC_POINT_bn2point failed: 0x%lx", ERR_get_error());
+
+        assert(EC_KEY_check_key(eckey) == 1);
+
+        r = BN_bin2bn(signature_r, signature_r_size, NULL);
+        if (!r)
+                return -EIO;
+
+        s = BN_bin2bn(signature_s, signature_s_size, NULL);
+        if (!s)
+                return -EIO;
+
+        /* TODO: We should eventually use use the EVP API once it supports ECDSA signature verification */
+
+        sig = ECDSA_SIG_new();
+        if (!sig)
+                return -ENOMEM;
+
+        if (ECDSA_SIG_set0(sig, r, s) <= 0)
+                return -EIO;
+        r = s = NULL;
+
+        k = ECDSA_do_verify(data, data_size, sig, eckey);
+        if (k < 0)
+                return log_debug_errno(SYNTHETIC_ERRNO(EIO),
+                                       "Signature verification failed: 0x%lx", ERR_get_error());
+
+        return k;
+
+#else
         gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL;
         gcry_mpi_t q = NULL, r = NULL, s = NULL;
         gcry_error_t ge;
@@ -315,16 +437,17 @@ finish:
                 gcry_sexp_release(data_sexp);
 
         return k;
+#endif
 }
 
 static int dnssec_ecdsa_verify(
-                const char *hash_algorithm,
+                hash_algorithm_t hash_algorithm,
                 int algorithm,
                 const void *hash, size_t hash_size,
                 DnsResourceRecord *rrsig,
                 DnsResourceRecord *dnskey) {
 
-        const char *curve;
+        elliptic_curve_t curve;
         size_t key_size;
         uint8_t *q;
 
@@ -334,11 +457,11 @@ static int dnssec_ecdsa_verify(
         assert(dnskey);
 
         if (algorithm == DNSSEC_ALGORITHM_ECDSAP256SHA256) {
+                curve = OPENSSL_OR_GCRYPT(NID_X9_62_prime256v1, "NIST P-256");  /* NIST P-256 */
                 key_size = 32;
-                curve = "NIST P-256";
         } else if (algorithm == DNSSEC_ALGORITHM_ECDSAP384SHA384) {
+                curve = OPENSSL_OR_GCRYPT(NID_secp384r1, "NIST P-384");         /* NIST P-384 */
                 key_size = 48;
-                curve = "NIST P-384";
         } else
                 return -EOPNOTSUPP;
 
@@ -361,25 +484,66 @@ static int dnssec_ecdsa_verify(
                         q, key_size*2+1);
 }
 
-#if GCRYPT_VERSION_NUMBER >= 0x010600
 static int dnssec_eddsa_verify_raw(
-                const char *curve,
+                elliptic_curve_t curve,
-                const void *signature_r, size_t signature_r_size,
+                const uint8_t *signature, size_t signature_size,
-                const void *signature_s, size_t signature_s_size,
+                const uint8_t *data, size_t data_size,
-                const void *data, size_t data_size,
+                const uint8_t *key, size_t key_size) {
-                const void *key, size_t key_size) {
 
+#if PREFER_OPENSSL
+        _cleanup_(EVP_PKEY_freep) EVP_PKEY *evkey = NULL;
+        _cleanup_(EVP_PKEY_CTX_freep) EVP_PKEY_CTX *pctx = NULL;
+        _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = NULL;
+        int r;
+
+        assert(curve == NID_ED25519);
+        assert(signature_size == key_size * 2);
+
+        uint8_t *q = newa(uint8_t, signature_size + 1);
+        q[0] = 0x04; /* Prepend 0x04 to indicate an uncompressed key */
+        memcpy(q+1, signature, signature_size);
+
+        evkey = EVP_PKEY_new_raw_public_key(EVP_PKEY_ED25519, NULL, key, key_size);
+        if (!evkey)
+                return log_debug_errno(SYNTHETIC_ERRNO(EIO),
+                                       "EVP_PKEY_new_raw_public_key failed: 0x%lx", ERR_get_error());
+
+        pctx = EVP_PKEY_CTX_new(evkey, NULL);
+        if (!pctx)
+                return -ENOMEM;
+
+        ctx = EVP_MD_CTX_new();
+        if (!ctx)
+                return -ENOMEM;
+
+        /* This prevents EVP_DigestVerifyInit from managing pctx and complicating our free logic. */
+        EVP_MD_CTX_set_pkey_ctx(ctx, pctx);
+
+        /* One might be tempted to use EVP_PKEY_verify_init, but see Ed25519(7ssl). */
+        if (EVP_DigestVerifyInit(ctx, &pctx, NULL, NULL, evkey) <= 0)
+                return -EIO;
+
+        r = EVP_DigestVerify(ctx, signature, signature_size, data, data_size);
+        if (r < 0)
+                return log_debug_errno(SYNTHETIC_ERRNO(EIO),
+                                       "Signature verification failed: 0x%lx", ERR_get_error());
+
+        return r;
+
+#elif GCRYPT_VERSION_NUMBER >= 0x010600
         gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL;
         gcry_error_t ge;
         int k;
 
+        assert(signature_size == key_size * 2);
+
         ge = gcry_sexp_build(&signature_sexp,
                              NULL,
                              "(sig-val (eddsa (r %b) (s %b)))",
-                             (int) signature_r_size,
+                             (int) key_size,
-                             signature_r,
+                             signature,
-                             (int) signature_s_size,
+                             (int) key_size,
-                             signature_s);
+                             signature + key_size);
         if (ge != 0) {
                 k = -EIO;
                 goto finish;
@@ -409,10 +573,10 @@ static int dnssec_eddsa_verify_raw(
         ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp);
         if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE)
                 k = 0;
-        else if (ge != 0) {
+        else if (ge != 0)
-                log_debug("EdDSA signature check failed: %s", gpg_strerror(ge));
+                k = log_debug_errno(SYNTHETIC_ERRNO(EIO),
-                k = -EIO;
+                                    "EdDSA signature check failed: %s", gpg_strerror(ge));
-        } else
+        else
                 k = 1;
 finish:
         if (public_key_sexp)
@@ -423,6 +587,9 @@ finish:
                 gcry_sexp_release(data_sexp);
 
         return k;
+#else
+        return -EOPNOTSUPP;
+#endif
 }
 
 static int dnssec_eddsa_verify(
@@ -430,11 +597,11 @@ static int dnssec_eddsa_verify(
                 const void *data, size_t data_size,
                 DnsResourceRecord *rrsig,
                 DnsResourceRecord *dnskey) {
-        const char *curve;
+        elliptic_curve_t curve;
         size_t key_size;
 
         if (algorithm == DNSSEC_ALGORITHM_ED25519) {
-                curve = "Ed25519";
+                curve = OPENSSL_OR_GCRYPT(NID_ED25519, "Ed25519");
                 key_size = 32;
         } else
                 return -EOPNOTSUPP;
@@ -447,20 +614,28 @@ static int dnssec_eddsa_verify(
 
         return dnssec_eddsa_verify_raw(
                         curve,
-                        rrsig->rrsig.signature, key_size,
+                        rrsig->rrsig.signature, rrsig->rrsig.signature_size,
-                        (uint8_t*) rrsig->rrsig.signature + key_size, key_size,
                         data, data_size,
                         dnskey->dnskey.key, key_size);
 }
-#endif
 
-static void md_add_uint8(gcry_md_hd_t md, uint8_t v) {
+static int md_add_uint8(hash_context_t ctx, uint8_t v) {
-        gcry_md_write(md, &v, sizeof(v));
+#if PREFER_OPENSSL
+        return EVP_DigestUpdate(ctx, &v, sizeof(v));
+#else
+        gcry_md_write(ctx, &v, sizeof(v));
+        return 0;
+#endif
 }
 
-static void md_add_uint16(gcry_md_hd_t md, uint16_t v) {
+static int md_add_uint16(hash_context_t ctx, uint16_t v) {
         v = htobe16(v);
-        gcry_md_write(md, &v, sizeof(v));
+#if PREFER_OPENSSL
+        return EVP_DigestUpdate(ctx, &v, sizeof(v));
+#else
+        gcry_md_write(ctx, &v, sizeof(v));
+        return 0;
+#endif
 }
 
 static void fwrite_uint8(FILE *fp, uint8_t v) {
@@ -565,36 +740,32 @@ static int dnssec_rrsig_expired(DnsResourceRecord *rrsig, usec_t realtime) {
         return realtime < inception || realtime > expiration;
 }
 
-static int algorithm_to_gcrypt_md(uint8_t algorithm) {
+static hash_md_t algorithm_to_implementation_id(uint8_t algorithm) {
 
-        /* Translates a DNSSEC signature algorithm into a gcrypt
+        /* Translates a DNSSEC signature algorithm into an openssl/gcrypt digest identifier.
-         * digest identifier.
          *
-         * Note that we implement all algorithms listed as "Must
+         * Note that we implement all algorithms listed as "Must implement" and "Recommended to Implement" in
-         * implement" and "Recommended to Implement" in RFC6944. We
+         * RFC6944. We don't implement any algorithms that are listed as "Optional" or "Must Not Implement".
-         * don't implement any algorithms that are listed as
+         * Specifically, we do not implement RSAMD5, DSASHA1, DH, DSA-NSEC3-SHA1, and GOST-ECC. */
-         * "Optional" or "Must Not Implement". Specifically, we do not
-         * implement RSAMD5, DSASHA1, DH, DSA-NSEC3-SHA1, and
-         * GOST-ECC. */
 
         switch (algorithm) {
 
         case DNSSEC_ALGORITHM_RSASHA1:
         case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1:
-                return GCRY_MD_SHA1;
+                return OPENSSL_OR_GCRYPT(EVP_sha1(), GCRY_MD_SHA1);
 
         case DNSSEC_ALGORITHM_RSASHA256:
         case DNSSEC_ALGORITHM_ECDSAP256SHA256:
-                return GCRY_MD_SHA256;
+                return OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256);
 
         case DNSSEC_ALGORITHM_ECDSAP384SHA384:
-                return GCRY_MD_SHA384;
+                return OPENSSL_OR_GCRYPT(EVP_sha384(), GCRY_MD_SHA384);
 
         case DNSSEC_ALGORITHM_RSASHA512:
-                return GCRY_MD_SHA512;
+                return OPENSSL_OR_GCRYPT(EVP_sha512(), GCRY_MD_SHA512);
 
         default:
-                return -EOPNOTSUPP;
+                return OPENSSL_OR_GCRYPT(NULL, -EOPNOTSUPP);
         }
 }
 
@@ -625,6 +796,183 @@ static void dnssec_fix_rrset_ttl(
         rrsig->expiry = rrsig->rrsig.expiration * USEC_PER_SEC;
 }
 
+static int dnssec_rrset_serialize_sig(
+                DnsResourceRecord *rrsig,
+                const char *source,
+                DnsResourceRecord **list,
+                size_t list_len,
+                bool wildcard,
+                char **ret_sig_data,
+                size_t *ret_sig_size) {
+
+        _cleanup_free_ char *sig_data = NULL;
+        size_t sig_size = 0;
+        _cleanup_fclose_ FILE *f = NULL;
+        uint8_t wire_format_name[DNS_WIRE_FORMAT_HOSTNAME_MAX];
+        DnsResourceRecord *rr;
+        int r;
+
+        assert(rrsig);
+        assert(source);
+        assert(list || list_len == 0);
+        assert(ret_sig_data);
+        assert(ret_sig_size);
+
+        f = open_memstream_unlocked(&sig_data, &sig_size);
+        if (!f)
+                return -ENOMEM;
+
+        fwrite_uint16(f, rrsig->rrsig.type_covered);
+        fwrite_uint8(f, rrsig->rrsig.algorithm);
+        fwrite_uint8(f, rrsig->rrsig.labels);
+        fwrite_uint32(f, rrsig->rrsig.original_ttl);
+        fwrite_uint32(f, rrsig->rrsig.expiration);
+        fwrite_uint32(f, rrsig->rrsig.inception);
+        fwrite_uint16(f, rrsig->rrsig.key_tag);
+
+        r = dns_name_to_wire_format(rrsig->rrsig.signer, wire_format_name, sizeof(wire_format_name), true);
+        if (r < 0)
+                return r;
+        fwrite(wire_format_name, 1, r, f);
+
+        /* Convert the source of synthesis into wire format */
+        r = dns_name_to_wire_format(source, wire_format_name, sizeof(wire_format_name), true);
+        if (r < 0)
+                return r;
+
+        for (size_t k = 0; k < list_len; k++) {
+                size_t l;
+
+                rr = list[k];
+
+                /* Hash the source of synthesis. If this is a wildcard, then prefix it with the *. label */
+                if (wildcard)
+                        fwrite((uint8_t[]) { 1, '*'}, sizeof(uint8_t), 2, f);
+                fwrite(wire_format_name, 1, r, f);
+
+                fwrite_uint16(f, rr->key->type);
+                fwrite_uint16(f, rr->key->class);
+                fwrite_uint32(f, rrsig->rrsig.original_ttl);
+
+                l = DNS_RESOURCE_RECORD_RDATA_SIZE(rr);
+                assert(l <= 0xFFFF);
+
+                fwrite_uint16(f, (uint16_t) l);
+                fwrite(DNS_RESOURCE_RECORD_RDATA(rr), 1, l, f);
+        }
+
+        r = fflush_and_check(f);
+        f = safe_fclose(f);  /* sig_data may be reallocated when f is closed. */
+        if (r < 0)
+                return r;
+
+        *ret_sig_data = TAKE_PTR(sig_data);
+        *ret_sig_size = sig_size;
+        return 0;
+}
+
+static int dnssec_rrset_verify_sig(
+                DnsResourceRecord *rrsig,
+                DnsResourceRecord *dnskey,
+                const char *sig_data,
+                size_t sig_size) {
+
+        assert(rrsig);
+        assert(dnskey);
+        assert(sig_data);
+        assert(sig_size > 0);
+
+        hash_md_t md_algorithm;
+
+#if PREFER_OPENSSL
+        uint8_t hash[EVP_MAX_MD_SIZE];
+        unsigned hash_size;
+#else
+        _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL;
+        void *hash;
+        size_t hash_size;
+
+        initialize_libgcrypt(false);
+#endif
+
+        switch (rrsig->rrsig.algorithm) {
+        case DNSSEC_ALGORITHM_ED25519:
+#if PREFER_OPENSSL || GCRYPT_VERSION_NUMBER >= 0x010600
+                return dnssec_eddsa_verify(
+                                rrsig->rrsig.algorithm,
+                                sig_data, sig_size,
+                                rrsig,
+                                dnskey);
+#endif
+        case DNSSEC_ALGORITHM_ED448:
+                return -EOPNOTSUPP;
+        default:
+                /* OK, the RRs are now in canonical order. Let's calculate the digest */
+                md_algorithm = algorithm_to_implementation_id(rrsig->rrsig.algorithm);
+#if PREFER_OPENSSL
+                if (!md_algorithm)
+                        return -EOPNOTSUPP;
+
+                _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = EVP_MD_CTX_new();
+                if (!ctx)
+                        return -ENOMEM;
+
+                if (EVP_DigestInit_ex(ctx, md_algorithm, NULL) <= 0)
+                        return -EIO;
+
+                if (EVP_DigestUpdate(ctx, sig_data, sig_size) <= 0)
+                        return -EIO;
+
+                if (EVP_DigestFinal_ex(ctx, hash, &hash_size) <= 0)
+                        return -EIO;
+
+                assert(hash_size > 0);
+
+#else
+                if (md_algorithm < 0)
+                        return md_algorithm;
+
+                gcry_error_t err = gcry_md_open(&md, md_algorithm, 0);
+                if (gcry_err_code(err) != GPG_ERR_NO_ERROR || !md)
+                        return -EIO;
+
+                hash_size = gcry_md_get_algo_dlen(md_algorithm);
+                assert(hash_size > 0);
+
+                gcry_md_write(md, sig_data, sig_size);
+
+                hash = gcry_md_read(md, 0);
+                if (!hash)
+                        return -EIO;
+#endif
+        }
+
+        switch (rrsig->rrsig.algorithm) {
+
+        case DNSSEC_ALGORITHM_RSASHA1:
+        case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1:
+        case DNSSEC_ALGORITHM_RSASHA256:
+        case DNSSEC_ALGORITHM_RSASHA512:
+                return dnssec_rsa_verify(
+                                OPENSSL_OR_GCRYPT(md_algorithm, gcry_md_algo_name(md_algorithm)),
+                                hash, hash_size,
+                                rrsig,
+                                dnskey);
+
+        case DNSSEC_ALGORITHM_ECDSAP256SHA256:
+        case DNSSEC_ALGORITHM_ECDSAP384SHA384:
+                return dnssec_ecdsa_verify(
+                                OPENSSL_OR_GCRYPT(md_algorithm, gcry_md_algo_name(md_algorithm)),
+                                rrsig->rrsig.algorithm,
+                                hash, hash_size,
+                                rrsig,
+                                dnskey);
+
+        default:
+                assert_not_reached();
+        }
+}
+
 int dnssec_verify_rrset(
                 DnsAnswer *a,
                 const DnsResourceKey *key,
@@ -633,18 +981,12 @@ int dnssec_verify_rrset(
                 usec_t realtime,
                 DnssecResult *result) {
 
-        uint8_t wire_format_name[DNS_WIRE_FORMAT_HOSTNAME_MAX];
         DnsResourceRecord **list, *rr;
         const char *source, *name;
-        _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL;
+        size_t n = 0, sig_size;
-        int r, md_algorithm;
-        size_t n = 0;
-        size_t sig_size = 0;
         _cleanup_free_ char *sig_data = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t hash_size;
-        void *hash;
         bool wildcard;
+        int r;
 
         assert(key);
         assert(rrsig);
@@ -746,123 +1088,15 @@ int dnssec_verify_rrset(
         /* Bring the RRs into canonical order */
         typesafe_qsort(list, n, rr_compare);
 
-        f = open_memstream_unlocked(&sig_data, &sig_size);
+        r = dnssec_rrset_serialize_sig(rrsig, source, list, n, wildcard,
-        if (!f)
+                                       &sig_data, &sig_size);
-                return -ENOMEM;
-
-        fwrite_uint16(f, rrsig->rrsig.type_covered);
-        fwrite_uint8(f, rrsig->rrsig.algorithm);
-        fwrite_uint8(f, rrsig->rrsig.labels);
-        fwrite_uint32(f, rrsig->rrsig.original_ttl);
-        fwrite_uint32(f, rrsig->rrsig.expiration);
-        fwrite_uint32(f, rrsig->rrsig.inception);
-        fwrite_uint16(f, rrsig->rrsig.key_tag);
-
-        r = dns_name_to_wire_format(rrsig->rrsig.signer, wire_format_name, sizeof(wire_format_name), true);
-        if (r < 0)
-                return r;
-        fwrite(wire_format_name, 1, r, f);
-
-        /* Convert the source of synthesis into wire format */
-        r = dns_name_to_wire_format(source, wire_format_name, sizeof(wire_format_name), true);
         if (r < 0)
                 return r;
 
-        for (size_t k = 0; k < n; k++) {
+        r = dnssec_rrset_verify_sig(rrsig, dnskey, sig_data, sig_size);
-                size_t l;
+        if (r == -EOPNOTSUPP) {
-
-                rr = list[k];
-
-                /* Hash the source of synthesis. If this is a wildcard, then prefix it with the *. label */
-                if (wildcard)
-                        fwrite((uint8_t[]) { 1, '*'}, sizeof(uint8_t), 2, f);
-                fwrite(wire_format_name, 1, r, f);
-
-                fwrite_uint16(f, rr->key->type);
-                fwrite_uint16(f, rr->key->class);
-                fwrite_uint32(f, rrsig->rrsig.original_ttl);
-
-                l = DNS_RESOURCE_RECORD_RDATA_SIZE(rr);
-                assert(l <= 0xFFFF);
-
-                fwrite_uint16(f, (uint16_t) l);
-                fwrite(DNS_RESOURCE_RECORD_RDATA(rr), 1, l, f);
-        }
-
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        initialize_libgcrypt(false);
-
-        switch (rrsig->rrsig.algorithm) {
-#if GCRYPT_VERSION_NUMBER >= 0x010600
-        case DNSSEC_ALGORITHM_ED25519:
-                break;
-#else
-        case DNSSEC_ALGORITHM_ED25519:
-#endif
-        case DNSSEC_ALGORITHM_ED448:
                 *result = DNSSEC_UNSUPPORTED_ALGORITHM;
                 return 0;
-        default: {
-                gcry_error_t err;
-
-                /* OK, the RRs are now in canonical order. Let's calculate the digest */
-                md_algorithm = algorithm_to_gcrypt_md(rrsig->rrsig.algorithm);
-                if (md_algorithm == -EOPNOTSUPP) {
-                        *result = DNSSEC_UNSUPPORTED_ALGORITHM;
-                        return 0;
-                }
-                if (md_algorithm < 0)
-                        return md_algorithm;
-
-                err = gcry_md_open(&md, md_algorithm, 0);
-                if (gcry_err_code(err) != GPG_ERR_NO_ERROR || !md)
-                        return -EIO;
-
-                hash_size = gcry_md_get_algo_dlen(md_algorithm);
-                assert(hash_size > 0);
-
-                gcry_md_write(md, sig_data, sig_size);
-
-                hash = gcry_md_read(md, 0);
-                if (!hash)
-                        return -EIO;
-        }
-        }
-
-        switch (rrsig->rrsig.algorithm) {
-
-        case DNSSEC_ALGORITHM_RSASHA1:
-        case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1:
-        case DNSSEC_ALGORITHM_RSASHA256:
-        case DNSSEC_ALGORITHM_RSASHA512:
-                r = dnssec_rsa_verify(
-                                gcry_md_algo_name(md_algorithm),
-                                hash, hash_size,
-                                rrsig,
-                                dnskey);
-                break;
-
-        case DNSSEC_ALGORITHM_ECDSAP256SHA256:
-        case DNSSEC_ALGORITHM_ECDSAP384SHA384:
-                r = dnssec_ecdsa_verify(
-                                gcry_md_algo_name(md_algorithm),
-                                rrsig->rrsig.algorithm,
-                                hash, hash_size,
-                                rrsig,
-                                dnskey);
-                break;
-#if GCRYPT_VERSION_NUMBER >= 0x010600
-        case DNSSEC_ALGORITHM_ED25519:
-                r = dnssec_eddsa_verify(
-                                rrsig->rrsig.algorithm,
-                                sig_data, sig_size,
-                                rrsig,
-                                dnskey);
-                break;
-#endif
         }
         if (r < 0)
                 return r;
@@ -1067,33 +1301,29 @@ int dnssec_has_rrsig(DnsAnswer *a, const DnsResourceKey *key) {
         return 0;
 }
 
-static int digest_to_gcrypt_md(uint8_t algorithm) {
+static hash_md_t digest_to_hash_md(uint8_t algorithm) {
 
-        /* Translates a DNSSEC digest algorithm into a gcrypt digest identifier */
+        /* Translates a DNSSEC digest algorithm into an openssl/gcrypt digest identifier */
 
         switch (algorithm) {
 
         case DNSSEC_DIGEST_SHA1:
-                return GCRY_MD_SHA1;
+                return OPENSSL_OR_GCRYPT(EVP_sha1(), GCRY_MD_SHA1);
 
         case DNSSEC_DIGEST_SHA256:
-                return GCRY_MD_SHA256;
+                return OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256);
 
         case DNSSEC_DIGEST_SHA384:
-                return GCRY_MD_SHA384;
+                return OPENSSL_OR_GCRYPT(EVP_sha384(), GCRY_MD_SHA384);
 
         default:
-                return -EOPNOTSUPP;
+                return OPENSSL_OR_GCRYPT(NULL, -EOPNOTSUPP);
         }
 }
 
 int dnssec_verify_dnskey_by_ds(DnsResourceRecord *dnskey, DnsResourceRecord *ds, bool mask_revoke) {
         uint8_t wire_format[DNS_WIRE_FORMAT_HOSTNAME_MAX];
-        _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL;
+        int r;
-        gcry_error_t err;
-        size_t hash_size;
-        int md_algorithm, r;
-        void *result;
 
         assert(dnskey);
         assert(ds);
@@ -1116,23 +1346,65 @@ int dnssec_verify_dnskey_by_ds(DnsResourceRecord *dnskey, DnsResourceRecord *ds,
         if (dnssec_keytag(dnskey, mask_revoke) != ds->ds.key_tag)
                 return 0;
 
-        initialize_libgcrypt(false);
+        r = dns_name_to_wire_format(dns_resource_key_name(dnskey->key), wire_format, sizeof wire_format, true);
+        if (r < 0)
+                return r;
 
-        md_algorithm = digest_to_gcrypt_md(ds->ds.digest_type);
+        hash_md_t md_algorithm = digest_to_hash_md(ds->ds.digest_type);
-        if (md_algorithm < 0)
-                return md_algorithm;
 
-        hash_size = gcry_md_get_algo_dlen(md_algorithm);
+#if PREFER_OPENSSL
+        if (!md_algorithm)
+                return -EOPNOTSUPP;
+
+        _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = NULL;
+        uint8_t result[EVP_MAX_MD_SIZE];
+
+        unsigned hash_size = EVP_MD_size(md_algorithm);
         assert(hash_size > 0);
 
         if (ds->ds.digest_size != hash_size)
                 return 0;
 
-        r = dns_name_to_wire_format(dns_resource_key_name(dnskey->key), wire_format, sizeof(wire_format), true);
+        ctx = EVP_MD_CTX_new();
-        if (r < 0)
+        if (!ctx)
-                return r;
+                return -ENOMEM;
 
-        err = gcry_md_open(&md, md_algorithm, 0);
+        if (EVP_DigestInit_ex(ctx, md_algorithm, NULL) <= 0)
+                return -EIO;
+
+        if (EVP_DigestUpdate(ctx, wire_format, r) <= 0)
+                return -EIO;
+
+        if (mask_revoke)
+                md_add_uint16(ctx, dnskey->dnskey.flags & ~DNSKEY_FLAG_REVOKE);
+        else
+                md_add_uint16(ctx, dnskey->dnskey.flags);
+
+        r = md_add_uint8(ctx, dnskey->dnskey.protocol);
+        if (r <= 0)
+                return r;
+        r = md_add_uint8(ctx, dnskey->dnskey.algorithm);
+        if (r <= 0)
+                return r;
+        if (EVP_DigestUpdate(ctx, dnskey->dnskey.key, dnskey->dnskey.key_size) <= 0)
+                return -EIO;
+
+        if (EVP_DigestFinal_ex(ctx, result, NULL) <= 0)
+                return -EIO;
+
+#else
+        if (md_algorithm < 0)
+                return -EOPNOTSUPP;
+
+        _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL;
+
+        size_t hash_size = gcry_md_get_algo_dlen(md_algorithm);
+        assert(hash_size > 0);
+
+        if (ds->ds.digest_size != hash_size)
+                return 0;
+
+        gcry_error_t err = gcry_md_open(&md, md_algorithm, 0);
         if (gcry_err_code(err) != GPG_ERR_NO_ERROR || !md)
                 return -EIO;
 
@@ -1145,9 +1417,10 @@ int dnssec_verify_dnskey_by_ds(DnsResourceRecord *dnskey, DnsResourceRecord *ds,
         md_add_uint8(md, dnskey->dnskey.algorithm);
         gcry_md_write(md, dnskey->dnskey.key, dnskey->dnskey.key_size);
 
-        result = gcry_md_read(md, 0);
+        void *result = gcry_md_read(md, 0);
         if (!result)
                 return -EIO;
+#endif
 
         return memcmp(result, ds->ds.digest, ds->ds.digest_size) == 0;
 }
@@ -1190,27 +1463,22 @@ int dnssec_verify_dnskey_by_ds_search(DnsResourceRecord *dnskey, DnsAnswer *vali
         return 0;
 }
 
-static int nsec3_hash_to_gcrypt_md(uint8_t algorithm) {
+static hash_md_t nsec3_hash_to_hash_md(uint8_t algorithm) {
 
-        /* Translates a DNSSEC NSEC3 hash algorithm into a gcrypt digest identifier */
+        /* Translates a DNSSEC NSEC3 hash algorithm into an openssl/gcrypt digest identifier */
 
         switch (algorithm) {
 
         case NSEC3_ALGORITHM_SHA1:
-                return GCRY_MD_SHA1;
+                return OPENSSL_OR_GCRYPT(EVP_sha1(), GCRY_MD_SHA1);
 
         default:
-                return -EOPNOTSUPP;
+                return OPENSSL_OR_GCRYPT(NULL, -EOPNOTSUPP);
         }
 }
 
 int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) {
         uint8_t wire_format[DNS_WIRE_FORMAT_HOSTNAME_MAX];
-        _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL;
-        gcry_error_t err;
-        size_t hash_size;
-        int algorithm;
-        void *result;
         int r;
 
         assert(nsec3);
@@ -1225,13 +1493,55 @@ int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) {
                                        "Ignoring NSEC3 RR %s with excessive number of iterations.",
                                        dns_resource_record_to_string(nsec3));
 
-        algorithm = nsec3_hash_to_gcrypt_md(nsec3->nsec3.algorithm);
+        hash_md_t algorithm = nsec3_hash_to_hash_md(nsec3->nsec3.algorithm);
+#if PREFER_OPENSSL
+        if (!algorithm)
+                return -EOPNOTSUPP;
+
+        size_t hash_size = EVP_MD_size(algorithm);
+        assert(hash_size > 0);
+
+        if (nsec3->nsec3.next_hashed_name_size != hash_size)
+                return -EINVAL;
+
+        _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = EVP_MD_CTX_new();
+        if (!ctx)
+                return -ENOMEM;
+
+        if (EVP_DigestInit_ex(ctx, algorithm, NULL) <= 0)
+                return -EIO;
+
+        r = dns_name_to_wire_format(name, wire_format, sizeof(wire_format), true);
+        if (r < 0)
+                return r;
+
+        if (EVP_DigestUpdate(ctx, wire_format, r) <= 0)
+                return -EIO;
+        if (EVP_DigestUpdate(ctx, nsec3->nsec3.salt, nsec3->nsec3.salt_size) <= 0)
+                return -EIO;
+
+        uint8_t result[EVP_MAX_MD_SIZE];
+        if (EVP_DigestFinal_ex(ctx, result, NULL) <= 0)
+                return -EIO;
+
+        for (unsigned k = 0; k < nsec3->nsec3.iterations; k++) {
+                if (EVP_DigestInit_ex(ctx, algorithm, NULL) <= 0)
+                        return -EIO;
+                if (EVP_DigestUpdate(ctx, result, hash_size) <= 0)
+                        return -EIO;
+                if (EVP_DigestUpdate(ctx, nsec3->nsec3.salt, nsec3->nsec3.salt_size) <= 0)
+                        return -EIO;
+
+                if (EVP_DigestFinal_ex(ctx, result, NULL) <= 0)
+                        return -EIO;
+        }
+#else
         if (algorithm < 0)
                 return algorithm;
 
         initialize_libgcrypt(false);
 
-        hash_size = gcry_md_get_algo_dlen(algorithm);
+        unsigned hash_size = gcry_md_get_algo_dlen(algorithm);
         assert(hash_size > 0);
 
         if (nsec3->nsec3.next_hashed_name_size != hash_size)
@@ -1241,14 +1551,15 @@ int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) {
         if (r < 0)
                 return r;
 
-        err = gcry_md_open(&md, algorithm, 0);
+        _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL;
+        gcry_error_t err = gcry_md_open(&md, algorithm, 0);
         if (gcry_err_code(err) != GPG_ERR_NO_ERROR || !md)
                 return -EIO;
 
         gcry_md_write(md, wire_format, r);
         gcry_md_write(md, nsec3->nsec3.salt, nsec3->nsec3.salt_size);
 
-        result = gcry_md_read(md, 0);
+        void *result = gcry_md_read(md, 0);
         if (!result)
                 return -EIO;
 
@@ -1264,6 +1575,7 @@ int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) {
                 if (!result)
                         return -EIO;
         }
+#endif
 
         memcpy(ret, result, hash_size);
         return (int) hash_size;
@@ -1283,8 +1595,14 @@ static int nsec3_is_good(DnsResourceRecord *rr, DnsResourceRecord *nsec3) {
                 return 0;
 
         /* Ignore NSEC3 RRs whose algorithm we don't know */
-        if (nsec3_hash_to_gcrypt_md(rr->nsec3.algorithm) < 0)
+#if PREFER_OPENSSL
+        if (!nsec3_hash_to_hash_md(rr->nsec3.algorithm))
                 return 0;
+#else
+        if (nsec3_hash_to_hash_md(rr->nsec3.algorithm) < 0)
+                return 0;
+#endif
+
         /* Ignore NSEC3 RRs with an excessive number of required iterations */
         if (rr->nsec3.iterations > NSEC3_ITERATIONS_MAX)
                 return 0;

src/resolve/resolved-dns-packet.c

@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 #if HAVE_GCRYPT
-#include <gcrypt.h>
+#  include <gcrypt.h>
 #endif
 
 #include "alloc-util.h"
@@ -776,7 +776,7 @@ int dns_packet_append_opt(
                 static const uint8_t rfc6975[] = {
 
                         0, 5, /* OPTION_CODE: DAU */
-#if HAVE_GCRYPT && GCRYPT_VERSION_NUMBER >= 0x010600
+#if PREFER_OPENSSL || (HAVE_GCRYPT && GCRYPT_VERSION_NUMBER >= 0x010600)
                         0, 7, /* LIST_LENGTH */
 #else
                         0, 6, /* LIST_LENGTH */
@@ -787,7 +787,7 @@ int dns_packet_append_opt(
                         DNSSEC_ALGORITHM_RSASHA512,
                         DNSSEC_ALGORITHM_ECDSAP256SHA256,
                         DNSSEC_ALGORITHM_ECDSAP384SHA384,
-#if HAVE_GCRYPT && GCRYPT_VERSION_NUMBER >= 0x010600
+#if PREFER_OPENSSL || (HAVE_GCRYPT && GCRYPT_VERSION_NUMBER >= 0x010600)
                         DNSSEC_ALGORITHM_ED25519,
 #endif
 

src/resolve/resolved-link.c

@@ -414,9 +414,9 @@ void link_set_dnssec_mode(Link *l, DnssecMode mode) {
 
         assert(l);
 
-#if ! HAVE_GCRYPT
+#if !HAVE_OPENSSL_OR_GCRYPT
         if (IN_SET(mode, DNSSEC_YES, DNSSEC_ALLOW_DOWNGRADE))
-                log_warning("DNSSEC option for the link cannot be enabled or set to allow-downgrade when systemd-resolved is built without gcrypt support. Turning off DNSSEC support.");
+                log_warning("DNSSEC option for the link cannot be enabled or set to allow-downgrade when systemd-resolved is built without a cryptographic library. Turning off DNSSEC support.");
         return;
 #endif
 

src/resolve/test-dnssec.c

@@ -1,20 +1,19 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 #include <arpa/inet.h>
-#if HAVE_GCRYPT
-#include <gcrypt.h>
-#endif
 #include <netinet/in.h>
 #include <sys/socket.h>
 
+#if HAVE_GCRYPT
+#  include <gcrypt.h>
+#endif
+
 #include "alloc-util.h"
 #include "resolved-dns-dnssec.h"
 #include "resolved-dns-rr.h"
 #include "string-util.h"
 #include "hexdecoct.h"
 
-#if HAVE_GCRYPT
-
 static void test_dnssec_verify_dns_key(void) {
 
         static const uint8_t ds1_fprint[] = {
@@ -173,8 +172,8 @@ static void test_dnssec_verify_rfc8080_ed25519_example1(void) {
         assert_se(dns_answer_add(answer, mx, 0, DNS_ANSWER_AUTHENTICATED, NULL) >= 0);
 
         assert_se(dnssec_verify_rrset(answer, mx->key, rrsig, dnskey,
-                                rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0);
+                                      rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0);
-#if GCRYPT_VERSION_NUMBER >= 0x010600
+#if PREFER_OPENSSL || GCRYPT_VERSION_NUMBER >= 0x010600
         assert_se(result == DNSSEC_VALIDATED);
 #else
         assert_se(result == DNSSEC_UNSUPPORTED_ALGORITHM);
@@ -265,13 +264,196 @@ static void test_dnssec_verify_rfc8080_ed25519_example2(void) {
         assert_se(dns_answer_add(answer, mx, 0, DNS_ANSWER_AUTHENTICATED, NULL) >= 0);
 
         assert_se(dnssec_verify_rrset(answer, mx->key, rrsig, dnskey,
-                                rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0);
+                                      rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0);
-#if GCRYPT_VERSION_NUMBER >= 0x010600
+#if PREFER_OPENSSL || GCRYPT_VERSION_NUMBER >= 0x010600
         assert_se(result == DNSSEC_VALIDATED);
 #else
         assert_se(result == DNSSEC_UNSUPPORTED_ALGORITHM);
 #endif
 }
+
+static void test_dnssec_verify_rfc6605_example1(void) {
+        static const uint8_t signature_blob[] = {
+                0xab, 0x1e, 0xb0, 0x2d, 0x8a, 0xa6, 0x87, 0xe9, 0x7d, 0xa0, 0x22, 0x93, 0x37, 0xaa, 0x88, 0x73,
+                0xe6, 0xf0, 0xeb, 0x26, 0xbe, 0x28, 0x9f, 0x28, 0x33, 0x3d, 0x18, 0x3f, 0x5d, 0x3b, 0x7a, 0x95,
+                0xc0, 0xc8, 0x69, 0xad, 0xfb, 0x74, 0x8d, 0xae, 0xe3, 0xc5, 0x28, 0x6e, 0xed, 0x66, 0x82, 0xc1,
+                0x2e, 0x55, 0x33, 0x18, 0x6b, 0xac, 0xed, 0x9c, 0x26, 0xc1, 0x67, 0xa9, 0xeb, 0xae, 0x95, 0x0b,
+        };
+
+        static const uint8_t ds_fprint[] = {
+                0x6f, 0x87, 0x3c, 0x73, 0x57, 0xde, 0xd9, 0xee, 0xf8, 0xef, 0xbd, 0x76, 0xed, 0xbd, 0xbb, 0xd7,
+                0x5e, 0x7a, 0xe7, 0xa6, 0x9d, 0xeb, 0x6e, 0x7a, 0x7f, 0x8d, 0xb8, 0xeb, 0x6e, 0x5b, 0x7f, 0x97,
+                0x35, 0x7b, 0x6e, 0xfb, 0xd1, 0xc7, 0xba, 0x77, 0xa7, 0xb7, 0xed, 0xd7, 0xfa, 0xd5, 0xdd, 0x7b,
+        };
+
+        static const uint8_t dnskey_blob[] = {
+                0x1a, 0x88, 0xc8, 0x86, 0x15, 0xd4, 0x37, 0xfb, 0xb8, 0xbf, 0x9e, 0x19, 0x42, 0xa1, 0x92, 0x9f,
+                0x28, 0x56, 0x27, 0x06, 0xae, 0x6c, 0x2b, 0xd3, 0x99, 0xe7, 0xb1, 0xbf, 0xb6, 0xd1, 0xe9, 0xe7,
+                0x5b, 0x92, 0xb4, 0xaa, 0x42, 0x91, 0x7a, 0xe1, 0xc6, 0x1b, 0x70, 0x1e, 0xf0, 0x35, 0xc3, 0xfe,
+                0x7b, 0xe3, 0x00, 0x9c, 0xba, 0xfe, 0x5a, 0x2f, 0x71, 0x31, 0x6c, 0x90, 0x2d, 0xcf, 0x0d, 0x00,
+        };
+
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *dnskey = NULL, *ds = NULL, *a = NULL,
+                *rrsig = NULL;
+        _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+        DnssecResult result;
+
+        dnskey = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNSKEY, "example.net.");
+        assert_se(dnskey);
+
+        dnskey->dnskey.flags = 257;
+        dnskey->dnskey.protocol = 3;
+        dnskey->dnskey.algorithm = DNSSEC_ALGORITHM_ECDSAP256SHA256;
+        dnskey->dnskey.key_size = sizeof(dnskey_blob);
+        dnskey->dnskey.key = memdup(dnskey_blob, sizeof(dnskey_blob));
+        assert_se(dnskey->dnskey.key);
+
+        log_info("DNSKEY: %s", strna(dns_resource_record_to_string(dnskey)));
+
+        ds = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DS, "example.net.");
+        assert_se(ds);
+
+        ds->ds.key_tag = 55648;
+        ds->ds.algorithm = DNSSEC_ALGORITHM_ECDSAP256SHA256;
+        ds->ds.digest_type = DNSSEC_DIGEST_SHA256;
+        ds->ds.digest_size = sizeof(ds_fprint);
+        ds->ds.digest = memdup(ds_fprint, ds->ds.digest_size);
+        assert_se(ds->ds.digest);
+
+        log_info("DS: %s", strna(dns_resource_record_to_string(ds)));
+
+        a = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, "www.example.net");
+        assert_se(a);
+
+        a->a.in_addr.s_addr = inet_addr("192.0.2.1");
+
+        log_info("A: %s", strna(dns_resource_record_to_string(a)));
+
+        rrsig = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_RRSIG, "www.example.net.");
+        assert_se(rrsig);
+
+        rrsig->rrsig.type_covered = DNS_TYPE_A;
+        rrsig->rrsig.algorithm = DNSSEC_ALGORITHM_ECDSAP256SHA256;
+        rrsig->rrsig.labels = 3;
+        rrsig->rrsig.expiration = 1284026679;
+        rrsig->rrsig.inception = 1281607479;
+        rrsig->rrsig.key_tag = 55648;
+        rrsig->rrsig.original_ttl = 3600;
+        rrsig->rrsig.signer = strdup("example.net.");
+        assert_se(rrsig->rrsig.signer);
+        rrsig->rrsig.signature_size = sizeof(signature_blob);
+        rrsig->rrsig.signature = memdup(signature_blob, rrsig->rrsig.signature_size);
+        assert_se(rrsig->rrsig.signature);
+
+        log_info("RRSIG: %s", strna(dns_resource_record_to_string(rrsig)));
+
+        assert_se(dnssec_key_match_rrsig(a->key, rrsig) > 0);
+        assert_se(dnssec_rrsig_match_dnskey(rrsig, dnskey, false) > 0);
+
+        answer = dns_answer_new(1);
+        assert_se(answer);
+        assert_se(dns_answer_add(answer, a, 0, DNS_ANSWER_AUTHENTICATED, NULL) >= 0);
+
+        assert_se(dnssec_verify_rrset(answer, a->key, rrsig, dnskey,
+                                      rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0);
+        assert_se(result == DNSSEC_VALIDATED);
+}
+
+static void test_dnssec_verify_rfc6605_example2(void) {
+        static const uint8_t signature_blob[] = {
+                0xfc, 0xbe, 0x61, 0x0c, 0xa2, 0x2f, 0x18, 0x3c, 0x88, 0xd5, 0xf7, 0x00, 0x45, 0x7d, 0xf3, 0xeb,
+                0x9a, 0xab, 0x98, 0xfb, 0x15, 0xcf, 0xbd, 0xd0, 0x0f, 0x53, 0x2b, 0xe4, 0x21, 0x2a, 0x3a, 0x22,
+                0xcf, 0xf7, 0x98, 0x71, 0x42, 0x8b, 0xae, 0xae, 0x81, 0x82, 0x79, 0x93, 0xaf, 0xcc, 0x56, 0xb1,
+                0xb1, 0x3f, 0x06, 0x96, 0xbe, 0xf8, 0x85, 0xb6, 0xaf, 0x44, 0xa6, 0xb2, 0x24, 0xdb, 0xb2, 0x74,
+                0x2b, 0xb3, 0x59, 0x34, 0x92, 0x3d, 0xdc, 0xfb, 0xc2, 0x7a, 0x97, 0x2f, 0x96, 0xdd, 0x70, 0x9c,
+                0xee, 0xb1, 0xd9, 0xc8, 0xd1, 0x14, 0x8c, 0x44, 0xec, 0x71, 0xc0, 0x68, 0xa9, 0x59, 0xc2, 0x66,
+
+        };
+
+        static const uint8_t ds_fprint[] = {
+                0xef, 0x67, 0x7b, 0x6f, 0xad, 0xbd, 0xef, 0xa7, 0x1e, 0xd3, 0xae, 0x37, 0xf1, 0xef, 0x5c, 0xd1,
+                0xb7, 0xf7, 0xd7, 0xdd, 0x35, 0xdd, 0xc7, 0xfc, 0xd3, 0x57, 0xf4, 0xf5, 0xe7, 0x1c, 0xf3, 0x86,
+                0xfc, 0x77, 0xb7, 0xbd, 0xe3, 0xde, 0x5f, 0xdb, 0xb7, 0xb7, 0xd3, 0x97, 0x3a, 0x6b, 0xd6, 0xf4,
+                0xe7, 0xad, 0xda, 0xf5, 0xbe, 0x5f, 0xe1, 0xdd, 0xbc, 0xf3, 0x8d, 0x39, 0x73, 0x7d, 0x34, 0xf1,
+                0xaf, 0x78, 0xe9, 0xd7, 0xfd, 0xf3, 0x77, 0x7a,
+        };
+
+        static const uint8_t dnskey_blob[] = {
+                0xc4, 0xa6, 0x1a, 0x36, 0x15, 0x9d, 0x18, 0xe7, 0xc9, 0xfa, 0x73, 0xeb, 0x2f, 0xcf, 0xda, 0xae,
+                0x4c, 0x1f, 0xd8, 0x46, 0x37, 0x30, 0x32, 0x7e, 0x48, 0x4a, 0xca, 0x8a, 0xf0, 0x55, 0x4a, 0xe9,
+                0xb5, 0xc3, 0xf7, 0xa0, 0xb1, 0x7b, 0xd2, 0x00, 0x3b, 0x4d, 0x26, 0x1c, 0x9e, 0x9b, 0x94, 0x42,
+                0x3a, 0x98, 0x10, 0xe8, 0xaf, 0x17, 0xd4, 0x34, 0x52, 0x12, 0x4a, 0xdb, 0x61, 0x0f, 0x8e, 0x07,
+                0xeb, 0xfc, 0xfe, 0xe5, 0xf8, 0xe4, 0xd0, 0x70, 0x63, 0xca, 0xe9, 0xeb, 0x91, 0x7a, 0x1a, 0x5b,
+                0xab, 0xf0, 0x8f, 0xe6, 0x95, 0x53, 0x60, 0x17, 0xa5, 0xbf, 0xa9, 0x32, 0x37, 0xee, 0x6e, 0x34,
+        };
+
+
+        _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *dnskey = NULL, *ds = NULL, *a = NULL,
+                *rrsig = NULL;
+        _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+        DnssecResult result;
+
+        dnskey = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNSKEY, "example.net.");
+        assert_se(dnskey);
+
+        dnskey->dnskey.flags = 257;
+        dnskey->dnskey.protocol = 3;
+        dnskey->dnskey.algorithm = DNSSEC_ALGORITHM_ECDSAP384SHA384;
+        dnskey->dnskey.key_size = sizeof(dnskey_blob);
+        dnskey->dnskey.key = memdup(dnskey_blob, sizeof(dnskey_blob));
+        assert_se(dnskey->dnskey.key);
+
+        log_info("DNSKEY: %s", strna(dns_resource_record_to_string(dnskey)));
+
+        ds = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DS, "example.net.");
+        assert_se(ds);
+
+        ds->ds.key_tag = 10771;
+        ds->ds.algorithm = DNSSEC_ALGORITHM_ECDSAP384SHA384;
+        ds->ds.digest_type = DNSSEC_DIGEST_SHA384;
+        ds->ds.digest_size = sizeof(ds_fprint);
+        ds->ds.digest = memdup(ds_fprint, ds->ds.digest_size);
+        assert_se(ds->ds.digest);
+
+        log_info("DS: %s", strna(dns_resource_record_to_string(ds)));
+
+        a = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, "www.example.net");
+        assert_se(a);
+
+        a->a.in_addr.s_addr = inet_addr("192.0.2.1");
+
+        log_info("A: %s", strna(dns_resource_record_to_string(a)));
+
+        rrsig = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_RRSIG, "www.example.net.");
+        assert_se(rrsig);
+
+        rrsig->rrsig.type_covered = DNS_TYPE_A;
+        rrsig->rrsig.algorithm = DNSSEC_ALGORITHM_ECDSAP384SHA384;
+        rrsig->rrsig.labels = 3;
+        rrsig->rrsig.expiration = 1284027625;
+        rrsig->rrsig.inception = 1281608425;
+        rrsig->rrsig.key_tag = 10771;
+        rrsig->rrsig.original_ttl = 3600;
+        rrsig->rrsig.signer = strdup("example.net.");
+        assert_se(rrsig->rrsig.signer);
+        rrsig->rrsig.signature_size = sizeof(signature_blob);
+        rrsig->rrsig.signature = memdup(signature_blob, rrsig->rrsig.signature_size);
+        assert_se(rrsig->rrsig.signature);
+
+        log_info("RRSIG: %s", strna(dns_resource_record_to_string(rrsig)));
+
+        assert_se(dnssec_key_match_rrsig(a->key, rrsig) > 0);
+        assert_se(dnssec_rrsig_match_dnskey(rrsig, dnskey, false) > 0);
+
+        answer = dns_answer_new(1);
+        assert_se(answer);
+        assert_se(dns_answer_add(answer, a, 0, DNS_ANSWER_AUTHENTICATED, NULL) >= 0);
+
+        assert_se(dnssec_verify_rrset(answer, a->key, rrsig, dnskey,
+                                      rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0);
+        assert_se(result == DNSSEC_VALIDATED);
+}
+
 static void test_dnssec_verify_rrset(void) {
 
         static const uint8_t signature_blob[] = {
@@ -605,19 +787,16 @@ static void test_dnssec_nsec3_hash(void) {
         assert_se(strcasecmp(b, "PJ8S08RR45VIQDAQGE7EN3VHKNROTBMM") == 0);
 }
 
-#endif
-
 int main(int argc, char *argv[]) {
-
-#if HAVE_GCRYPT
         test_dnssec_verify_dns_key();
         test_dnssec_verify_rfc8080_ed25519_example1();
         test_dnssec_verify_rfc8080_ed25519_example2();
+        test_dnssec_verify_rfc6605_example1();
+        test_dnssec_verify_rfc6605_example2();
         test_dnssec_verify_rrset();
         test_dnssec_verify_rrset2();
         test_dnssec_verify_rrset3();
         test_dnssec_nsec3_hash();
-#endif
 
         return 0;
 }

src/shared/openssl-util.c

@@ -2,8 +2,46 @@
 
 #include "openssl-util.h"
 #include "alloc-util.h"
+#include "hexdecoct.h"
 
 #if HAVE_OPENSSL
+int openssl_hash(const EVP_MD *alg,
+                 const void *msg,
+                 size_t msg_len,
+                 uint8_t *ret_hash,
+                 size_t *ret_hash_len) {
+
+        _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = NULL;
+        unsigned len;
+        int r;
+
+        ctx = EVP_MD_CTX_new();
+        if (!ctx)
+                /* This function just calls OPENSSL_zalloc, so failure
+                 * here is almost certainly a failed allocation. */
+                return -ENOMEM;
+
+        /* The documentation claims EVP_DigestInit behaves just like
+         * EVP_DigestInit_ex if passed NULL, except it also calls
+         * EVP_MD_CTX_reset, which deinitializes the context. */
+        r = EVP_DigestInit_ex(ctx, alg, NULL);
+        if (r == 0)
+                return -EIO;
+
+        r = EVP_DigestUpdate(ctx, msg, msg_len);
+        if (r == 0)
+                return -EIO;
+
+        r = EVP_DigestFinal_ex(ctx, ret_hash, &len);
+        if (r == 0)
+                return -EIO;
+
+        if (ret_hash_len)
+                *ret_hash_len = len;
+
+        return 0;
+}
+
 int rsa_encrypt_bytes(
                 EVP_PKEY *pkey,
                 const void *decrypted_key,
@@ -70,4 +108,33 @@ int rsa_pkey_to_suitable_key_size(
         *ret_suitable_key_size = suitable_key_size;
         return 0;
 }
+
+#  if PREFER_OPENSSL
+int string_hashsum(
+                const char *s,
+                size_t len,
+                const EVP_MD *md_algorithm,
+                char **ret) {
+
+        uint8_t hash[EVP_MAX_MD_SIZE];
+        size_t hash_size;
+        char *enc;
+        int r;
+
+        hash_size = EVP_MD_size(md_algorithm);
+        assert(hash_size > 0);
+
+        r = openssl_hash(md_algorithm, s, len, hash, NULL);
+        if (r < 0)
+                return r;
+
+        enc = hexmem(hash, hash_size);
+        if (!enc)
+                return -ENOMEM;
+
+        *ret = enc;
+        return 0;
+
+}
+#  endif
 #endif

src/shared/openssl-util.h

@@ -5,6 +5,8 @@
 
 #if HAVE_OPENSSL
 #  include <openssl/bio.h>
+#  include <openssl/bn.h>
+#  include <openssl/err.h>
 #  include <openssl/evp.h>
 #  include <openssl/pkcs7.h>
 #  include <openssl/ssl.h>
@@ -13,7 +15,15 @@
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(X509*, X509_free, NULL);
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(X509_NAME*, X509_NAME_free, NULL);
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EVP_PKEY_CTX*, EVP_PKEY_CTX_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EVP_PKEY*, EVP_PKEY_free, NULL);
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EVP_CIPHER_CTX*, EVP_CIPHER_CTX_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(RSA*, RSA_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EC_KEY*, EC_KEY_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EC_POINT*, EC_POINT_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EC_GROUP*, EC_GROUP_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(BIGNUM*, BN_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(BN_CTX*, BN_CTX_free, NULL);
+DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(ECDSA_SIG*, ECDSA_SIG_free, NULL);
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(PKCS7*, PKCS7_free, NULL);
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(SSL*, SSL_free, NULL);
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(BIO*, BIO_free, NULL);
@@ -26,8 +36,41 @@ static inline void sk_X509_free_allp(STACK_OF(X509) **sk) {
         sk_X509_pop_free(*sk, X509_free);
 }
 
+int openssl_hash(const EVP_MD *alg, const void *msg, size_t msg_len, uint8_t *ret_hash, size_t *ret_hash_len);
+
 int rsa_encrypt_bytes(EVP_PKEY *pkey, const void *decrypted_key, size_t decrypted_key_size, void **ret_encrypt_key, size_t *ret_encrypt_key_size);
 
 int rsa_pkey_to_suitable_key_size(EVP_PKEY *pkey, size_t *ret_suitable_key_size);
-
+#endif
+
+#if PREFER_OPENSSL
+/* The openssl definition */
+typedef const EVP_MD* hash_md_t;
+typedef const EVP_MD* hash_algorithm_t;
+typedef int elliptic_curve_t;
+typedef EVP_MD_CTX* hash_context_t;
+#  define OPENSSL_OR_GCRYPT(a, b) (a)
+
+#elif HAVE_GCRYPT
+
+#  include <gcrypt.h>
+
+/* The gcrypt definition */
+typedef int hash_md_t;
+typedef const char* hash_algorithm_t;
+typedef const char* elliptic_curve_t;
+typedef gcry_md_hd_t hash_context_t;
+#  define OPENSSL_OR_GCRYPT(a, b) (b)
+#endif
+
+#if PREFER_OPENSSL
+int string_hashsum(const char *s, size_t len, hash_algorithm_t md_algorithm, char **ret);
+
+static inline int string_hashsum_sha224(const char *s, size_t len, char **ret) {
+        return string_hashsum(s, len, EVP_sha224(), ret);
+}
+
+static inline int string_hashsum_sha256(const char *s, size_t len, char **ret) {
+        return string_hashsum(s, len, EVP_sha256(), ret);
+}
 #endif

src/test/meson.build

@@ -594,8 +594,10 @@ tests += [
 
         [['src/test/test-id128.c']],
 
-        [['src/test/test-gcrypt-util.c'],
+        [['src/test/test-cryptolib.c'],
-         [], [], [], 'HAVE_GCRYPT'],
+         [libshared],
+         [lib_openssl_or_gcrypt],
+         [], 'HAVE_OPENSSL_OR_GCRYPT'],
 
         [['src/test/test-nss-hosts.c',
           'src/test/nss-test-util.c',

src/test/test-cryptolib.c

@@ -3,25 +3,34 @@
 #include "alloc-util.h"
 #include "gcrypt-util.h"
 #include "macro.h"
+#include "openssl-util.h"
 #include "string-util.h"
 #include "tests.h"
 
 TEST(string_hashsum) {
         _cleanup_free_ char *out1 = NULL, *out2 = NULL, *out3 = NULL, *out4 = NULL;
 
-        assert_se(string_hashsum("asdf", 4, GCRY_MD_SHA224, &out1) == 0);
+        assert_se(string_hashsum("asdf", 4,
+                                 OPENSSL_OR_GCRYPT(EVP_sha224(), GCRY_MD_SHA224),
+                                 &out1) == 0);
         /* echo -n 'asdf' | sha224sum - */
         assert_se(streq(out1, "7872a74bcbf298a1e77d507cd95d4f8d96131cbbd4cdfc571e776c8a"));
 
-        assert_se(string_hashsum("asdf", 4, GCRY_MD_SHA256, &out2) == 0);
+        assert_se(string_hashsum("asdf", 4,
+                                 OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256),
+                                 &out2) == 0);
         /* echo -n 'asdf' | sha256sum - */
         assert_se(streq(out2, "f0e4c2f76c58916ec258f246851bea091d14d4247a2fc3e18694461b1816e13b"));
 
-        assert_se(string_hashsum("", 0, GCRY_MD_SHA224, &out3) == 0);
+        assert_se(string_hashsum("", 0,
+                                 OPENSSL_OR_GCRYPT(EVP_sha224(), GCRY_MD_SHA224),
+                                 &out3) == 0);
         /* echo -n '' | sha224sum - */
         assert_se(streq(out3, "d14a028c2a3a2bc9476102bb288234c415a2b01f828ea62ac5b3e42f"));
 
-        assert_se(string_hashsum("", 0, GCRY_MD_SHA256, &out4) == 0);
+        assert_se(string_hashsum("", 0,
+                                 OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256),
+                                 &out4) == 0);
         /* echo -n '' | sha256sum - */
         assert_se(streq(out4, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"));
 }