PROV SERIALIZER: add support for writing DH keys and parameters

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10394)

10 files changed, 722 insertions, 0 deletions

diff --git a/providers/common/include/prov/providercommonerr.h b/providers/common/include/prov/providercommonerr.h
index 5493ed5879..85e5856d30 100644
--- a/providers/common/include/prov/providercommonerr.h
+++ b/providers/common/include/prov/providercommonerr.h
@@ -53,6 +53,7 @@ int ERR_load_PROV_strings(void);
 # define PROV_R_BAD_DECRYPT                               100
 # define PROV_R_BAD_ENCODING                              141
 # define PROV_R_BAD_LENGTH                                142
+# define PROV_R_BN_ERROR                                  160
 # define PROV_R_BOTH_MODE_AND_MODE_INT                    127
 # define PROV_R_CIPHER_OPERATION_FAILED                   102
 # define PROV_R_FAILED_TO_GENERATE_KEY                    121
diff --git a/providers/common/provider_err.c b/providers/common/provider_err.c
index 440efe5bbf..7cae969c79 100644
--- a/providers/common/provider_err.c
+++ b/providers/common/provider_err.c
@@ -19,6 +19,7 @@ static const ERR_STRING_DATA PROV_str_reasons[] = {
     {ERR_PACK(ERR_LIB_PROV, 0, PROV_R_BAD_DECRYPT), "bad decrypt"},
     {ERR_PACK(ERR_LIB_PROV, 0, PROV_R_BAD_ENCODING), "bad encoding"},
     {ERR_PACK(ERR_LIB_PROV, 0, PROV_R_BAD_LENGTH), "bad length"},
+    {ERR_PACK(ERR_LIB_PROV, 0, PROV_R_BN_ERROR), "bn error"},
     {ERR_PACK(ERR_LIB_PROV, 0, PROV_R_BOTH_MODE_AND_MODE_INT),
     "both mode and mode int"},
     {ERR_PACK(ERR_LIB_PROV, 0, PROV_R_CIPHER_OPERATION_FAILED),
diff --git a/providers/defltprov.c b/providers/defltprov.c
index 84e580366d..b8e96f9c21 100644
--- a/providers/defltprov.c
+++ b/providers/defltprov.c
@@ -399,6 +399,25 @@ static const OSSL_ALGORITHM deflt_serializer[] = {
     { "RSA", "default=yes,format=pem,type=public",
       rsa_pub_pem_serializer_functions },
 
+    { "DH", "default=yes,format=text,type=private",
+      dh_priv_text_serializer_functions },
+    { "DH", "default=yes,format=text,type=public",
+      dh_pub_text_serializer_functions },
+    { "DH", "default=yes,format=text,type=domainparams",
+      dh_param_text_serializer_functions },
+    { "DH", "default=yes,format=der,type=private",
+      dh_priv_der_serializer_functions },
+    { "DH", "default=yes,format=der,type=public",
+      dh_pub_der_serializer_functions },
+    { "DH", "default=yes,format=der,type=domainparams",
+      dh_param_der_serializer_functions },
+    { "DH", "default=yes,format=pem,type=private",
+      dh_priv_pem_serializer_functions },
+    { "DH", "default=yes,format=pem,type=public",
+      dh_pub_pem_serializer_functions },
+    { "DH", "default=yes,format=pem,type=domainparams",
+      dh_param_pem_serializer_functions },
+
     { NULL, NULL, NULL }
 };
 
diff --git a/providers/implementations/include/prov/implementations.h b/providers/implementations/include/prov/implementations.h
index 438f9a25fa..3142a66233 100644
--- a/providers/implementations/include/prov/implementations.h
+++ b/providers/implementations/include/prov/implementations.h
@@ -269,3 +269,12 @@ extern const OSSL_DISPATCH rsa_priv_der_serializer_functions[];
 extern const OSSL_DISPATCH rsa_pub_der_serializer_functions[];
 extern const OSSL_DISPATCH rsa_priv_pem_serializer_functions[];
 extern const OSSL_DISPATCH rsa_pub_pem_serializer_functions[];
+extern const OSSL_DISPATCH dh_priv_text_serializer_functions[];
+extern const OSSL_DISPATCH dh_pub_text_serializer_functions[];
+extern const OSSL_DISPATCH dh_param_text_serializer_functions[];
+extern const OSSL_DISPATCH dh_priv_der_serializer_functions[];
+extern const OSSL_DISPATCH dh_pub_der_serializer_functions[];
+extern const OSSL_DISPATCH dh_param_der_serializer_functions[];
+extern const OSSL_DISPATCH dh_priv_pem_serializer_functions[];
+extern const OSSL_DISPATCH dh_pub_pem_serializer_functions[];
+extern const OSSL_DISPATCH dh_param_pem_serializer_functions[];
diff --git a/providers/implementations/serializers/build.info b/providers/implementations/serializers/build.info
index 8dc5376183..eee59366c8 100644
--- a/providers/implementations/serializers/build.info
+++ b/providers/implementations/serializers/build.info
@@ -3,6 +3,8 @@
 
 $SERIALIZER_GOAL=../../libimplementations.a
 $RSA_GOAL=../../libimplementations.a
+$DH_GOAL=../../libimplementations.a
 
 SOURCE[$SERIALIZER_GOAL]=serializer_common.c
 SOURCE[$RSA_GOAL]=serializer_rsa.c serializer_rsa_priv.c serializer_rsa_pub.c
+SOURCE[$DH_GOAL]=serializer_dh.c serializer_dh_priv.c serializer_dh_pub.c serializer_dh_param.c
diff --git a/providers/implementations/serializers/serializer_dh.c b/providers/implementations/serializers/serializer_dh.c
new file mode 100644
index 0000000000..313fae0e30
--- /dev/null
+++ b/providers/implementations/serializers/serializer_dh.c
@@ -0,0 +1,151 @@
+/*
+ * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/dh.h>
+#include <openssl/err.h>
+#include "prov/bio.h"             /* ossl_prov_bio_printf() */
+#include "prov/implementations.h" /* rsa_keymgmt_functions */
+#include "prov/providercommonerr.h" /* PROV_R_BN_ERROR */
+#include "serializer_local.h"
+
+OSSL_OP_keymgmt_importkey_fn *ossl_prov_get_dh_importkey(void)
+{
+    return ossl_prov_get_importkey(dh_keymgmt_functions);
+}
+
+int ossl_prov_print_dh(BIO *out, DH *dh, enum dh_print_type type)
+{
+    const char *type_label = NULL;
+    const BIGNUM *priv_key = NULL, *pub_key = NULL;
+    const BIGNUM *p = NULL, *g = NULL;
+
+
+    switch (type) {
+    case dh_print_priv:
+        type_label = "DH Private-Key";
+        break;
+    case dh_print_pub:
+        type_label = "DH Public-Key";
+        break;
+    case dh_print_params:
+        type_label = "DH Parameters";
+        break;
+    }
+
+    if (type == dh_print_priv) {
+        priv_key = DH_get0_priv_key(dh);
+        if (priv_key == NULL)
+            goto null_err;
+    }
+
+    if (type == dh_print_priv || type == dh_print_pub) {
+        pub_key = DH_get0_pub_key(dh);
+        if (pub_key == NULL)
+            goto null_err;
+    }
+
+    p = DH_get0_p(dh);
+    g = DH_get0_p(dh);
+    if (p == NULL || g == NULL)
+        goto null_err;
+
+    /*
+     * TODO(3.0): add printing of:
+     *
+     * - q (label "subgroup order:")
+     * - j (label "subgroup factor:")
+     * - seed (label "seed:")
+     * - counter (label "counter:")
+     *
+     * This can happen as soon as there are DH_get0_ functions for them.
+     */
+
+    if (ossl_prov_bio_printf(out, "%s: (%d bit)\n", type_label, BN_num_bits(p))
+        <= 0)
+        goto err;
+    if (priv_key != NULL
+        && !ossl_prov_print_labeled_bignum(out, "    private-key:", priv_key))
+        goto err;
+    if (pub_key != NULL
+        && !ossl_prov_print_labeled_bignum(out, "    public-key:", pub_key))
+        goto err;
+    if (p != NULL
+        && !ossl_prov_print_labeled_bignum(out, "    prime:", p))
+        goto err;
+    if (g != NULL
+        && !ossl_prov_print_labeled_bignum(out, "    generator:", g))
+        goto err;
+
+    return 1;
+ err:
+    return 0;
+ null_err:
+    ERR_raise(ERR_LIB_PROV, ERR_R_PASSED_NULL_PARAMETER);
+    goto err;
+}
+
+int ossl_prov_prepare_dh_params(const void *dh, int nid,
+                                ASN1_STRING **pstr, int *pstrtype)
+{
+    ASN1_STRING *params = ASN1_STRING_new();
+
+    if (params == NULL) {
+        ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
+        return 0;
+    }
+
+    if (nid == EVP_PKEY_DHX)
+        params->length = i2d_DHxparams(dh, &params->data);
+    else
+        params->length = i2d_DHparams(dh, &params->data);
+
+    if (params->length <= 0) {
+        ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
+        ASN1_STRING_free(params);
+        return 0;
+    }
+    params->type = V_ASN1_SEQUENCE;
+
+    *pstr = params;
+    *pstrtype = V_ASN1_SEQUENCE;
+    return 1;
+}
+
+int ossl_prov_dh_pub_to_der(const void *dh, unsigned char **pder)
+{
+    ASN1_INTEGER *pub_key = BN_to_ASN1_INTEGER(DH_get0_pub_key(dh), NULL);
+    int ret;
+
+    if (pub_key == NULL) {
+        ERR_raise(ERR_LIB_PROV, PROV_R_BN_ERROR);
+        return 0;
+    }
+
+    ret = i2d_ASN1_INTEGER(pub_key, pder);
+
+    ASN1_STRING_clear_free(pub_key);
+    return ret;
+}
+
+int ossl_prov_dh_priv_to_der(const void *dh, unsigned char **pder)
+{
+    ASN1_INTEGER *priv_key = BN_to_ASN1_INTEGER(DH_get0_priv_key(dh), NULL);
+    int ret;
+
+    if (priv_key == NULL) {
+        ERR_raise(ERR_LIB_PROV, PROV_R_BN_ERROR);
+        return 0;
+    }
+
+    ret = i2d_ASN1_INTEGER(priv_key, pder);
+
+    ASN1_STRING_clear_free(priv_key);
+    return ret;
+}
+
diff --git a/providers/implementations/serializers/serializer_dh_param.c b/providers/implementations/serializers/serializer_dh_param.c
new file mode 100644
index 0000000000..ca3371e19f
--- /dev/null
+++ b/providers/implementations/serializers/serializer_dh_param.c
@@ -0,0 +1,135 @@
+/*
+ * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/core_numbers.h>
+#include <openssl/pem.h>
+#include <openssl/dh.h>
+#include <openssl/types.h>
+#include <openssl/params.h>
+#include "prov/bio.h"
+#include "prov/implementations.h"
+#include "prov/providercommonerr.h"
+#include "serializer_local.h"
+
+static OSSL_OP_serializer_newctx_fn dh_param_newctx;
+static OSSL_OP_serializer_freectx_fn dh_param_freectx;
+static OSSL_OP_serializer_serialize_data_fn dh_param_der_data;
+static OSSL_OP_serializer_serialize_object_fn dh_param_der;
+static OSSL_OP_serializer_serialize_data_fn dh_param_pem_data;
+static OSSL_OP_serializer_serialize_object_fn dh_param_pem;
+
+static OSSL_OP_serializer_serialize_data_fn dh_param_print_data;
+static OSSL_OP_serializer_serialize_object_fn dh_param_print;
+
+/* Parameters : context */
+
+/*
+ * There's no specific implementation context, so we use the provider context
+ */
+static void *dh_param_newctx(void *provctx)
+{
+    return provctx;
+}
+
+static void dh_param_freectx(void *ctx)
+{
+}
+
+/* Public key : DER */
+static int dh_param_der_data(void *ctx, const OSSL_PARAM params[], BIO *out,
+                             OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx, params); /* ctx == provctx */
+
+        ok = dh_param_der(ctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_param_der(void *ctx, void *dh, BIO *out,
+                        OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    return i2d_DHparams_bio(out, dh);
+}
+
+/* Public key : PEM */
+static int dh_param_pem_data(void *ctx, const OSSL_PARAM params[], BIO *out,
+                            OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx, params); /* ctx == provctx */
+
+        ok = dh_param_pem(ctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_param_pem(void *ctx, void *dh, BIO *out,
+                       OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    return PEM_write_bio_DHparams(out, dh);
+}
+
+static int dh_param_print_data(void *ctx, const OSSL_PARAM params[], BIO *out,
+                              OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx, params); /* ctx == provctx */
+
+        ok = dh_param_print(ctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_param_print(void *ctx, void *dh, BIO *out,
+                         OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    return ossl_prov_print_dh(out, dh, dh_print_params);
+}
+
+const OSSL_DISPATCH dh_param_der_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_param_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_param_freectx },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA, (void (*)(void))dh_param_der_data },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_param_der },
+    { 0, NULL }
+};
+
+const OSSL_DISPATCH dh_param_pem_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_param_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_param_freectx },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA, (void (*)(void))dh_param_pem_data },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_param_pem },
+    { 0, NULL }
+};
+
+const OSSL_DISPATCH dh_param_text_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_param_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_param_freectx },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_param_print },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA,
+      (void (*)(void))dh_param_print_data },
+    { 0, NULL }
+};
diff --git a/providers/implementations/serializers/serializer_dh_priv.c b/providers/implementations/serializers/serializer_dh_priv.c
new file mode 100644
index 0000000000..80d87ac738
--- /dev/null
+++ b/providers/implementations/serializers/serializer_dh_priv.c
@@ -0,0 +1,250 @@
+/*
+ * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/core_numbers.h>
+#include <openssl/core_names.h>
+#include <openssl/err.h>
+#include <openssl/pem.h>
+#include <openssl/dh.h>
+#include <openssl/types.h>
+#include <openssl/params.h>
+#include "prov/bio.h"
+#include "prov/implementations.h"
+#include "serializer_local.h"
+
+static OSSL_OP_serializer_newctx_fn dh_priv_newctx;
+static OSSL_OP_serializer_freectx_fn dh_priv_freectx;
+static OSSL_OP_serializer_set_ctx_params_fn dh_priv_set_ctx_params;
+static OSSL_OP_serializer_settable_ctx_params_fn dh_priv_settable_ctx_params;
+static OSSL_OP_serializer_serialize_data_fn dh_priv_der_data;
+static OSSL_OP_serializer_serialize_object_fn dh_priv_der;
+static OSSL_OP_serializer_serialize_data_fn dh_pem_priv_data;
+static OSSL_OP_serializer_serialize_object_fn dh_pem_priv;
+
+static OSSL_OP_serializer_newctx_fn dh_print_newctx;
+static OSSL_OP_serializer_freectx_fn dh_print_freectx;
+static OSSL_OP_serializer_serialize_data_fn dh_priv_print_data;
+static OSSL_OP_serializer_serialize_object_fn dh_priv_print;
+
+ /*
+ * Context used for private key serialization.
+ */
+struct dh_priv_ctx_st {
+    void *provctx;
+
+    struct pkcs8_encrypt_ctx_st sc;
+};
+
+/* Private key : context */
+static void *dh_priv_newctx(void *provctx)
+{
+    struct dh_priv_ctx_st *ctx = OPENSSL_zalloc(sizeof(*ctx));
+
+    if (ctx != NULL) {
+        ctx->provctx = provctx;
+    }
+
+    /* -1 is the "whatever" indicator, i.e. the PKCS8 library default PBE */
+    ctx->sc.pbe_nid = -1;
+
+    return ctx;
+}
+
+static void dh_priv_freectx(void *vctx)
+{
+    struct dh_priv_ctx_st *ctx = vctx;
+
+    EVP_CIPHER_free(ctx->sc.cipher);
+    OPENSSL_free(ctx->sc.cipher_pass);
+    OPENSSL_free(ctx);
+}
+
+static const OSSL_PARAM *dh_priv_settable_ctx_params(void)
+{
+    static const OSSL_PARAM settables[] = {
+        OSSL_PARAM_utf8_string(OSSL_SERIALIZER_PARAM_CIPHER, NULL, 0),
+        OSSL_PARAM_octet_string(OSSL_SERIALIZER_PARAM_PASS, NULL, 0),
+        OSSL_PARAM_END,
+    };
+
+    return settables;
+}
+
+static int dh_priv_set_ctx_params(void *vctx, const OSSL_PARAM params[])
+{
+    struct dh_priv_ctx_st *ctx = vctx;
+    const OSSL_PARAM *p;
+
+    if ((p = OSSL_PARAM_locate_const(params, OSSL_SERIALIZER_PARAM_CIPHER))
+        != NULL) {
+        const OSSL_PARAM *propsp =
+            OSSL_PARAM_locate_const(params, OSSL_SERIALIZER_PARAM_PROPERTIES);
+        const char *props = NULL;
+
+        if (p->data_type != OSSL_PARAM_UTF8_STRING)
+            return 0;
+        if (propsp != NULL && propsp->data_type != OSSL_PARAM_UTF8_STRING)
+            return 0;
+        props = (propsp != NULL ? propsp->data : NULL);
+
+        EVP_CIPHER_free(ctx->sc.cipher);
+        ctx->sc.cipher_intent = p->data != NULL;
+        if (p->data != NULL
+            && ((ctx->sc.cipher = EVP_CIPHER_fetch(NULL, p->data, props))
+                == NULL))
+            return 0;
+    }
+    if ((p = OSSL_PARAM_locate_const(params, OSSL_SERIALIZER_PARAM_PASS))
+        != NULL) {
+        OPENSSL_free(ctx->sc.cipher_pass);
+        ctx->sc.cipher_pass = NULL;
+        if (!OSSL_PARAM_get_octet_string(p, &ctx->sc.cipher_pass, 0,
+                                         &ctx->sc.cipher_pass_length))
+            return 0;
+    }
+    return 1;
+}
+
+/* Private key : DER */
+static int dh_priv_der_data(void *vctx, const OSSL_PARAM params[], BIO *out,
+                             OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    struct dh_priv_ctx_st *ctx = vctx;
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx->provctx, params);
+
+        ok = dh_priv_der(ctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_priv_der(void *vctx, void *dh, BIO *out,
+                        OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    struct dh_priv_ctx_st *ctx = vctx;
+    int ret;
+
+    ctx->sc.cb = cb;
+    ctx->sc.cbarg = cbarg;
+
+    ret = ossl_prov_write_priv_der_from_obj(out, dh, EVP_PKEY_DH,
+                                            ossl_prov_prepare_dh_params,
+                                            ossl_prov_dh_priv_to_der,
+                                            &ctx->sc);
+
+    return ret;
+}
+
+/* Private key : PEM */
+static int dh_pem_priv_data(void *vctx, const OSSL_PARAM params[], BIO *out,
+                             OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    struct dh_priv_ctx_st *ctx = vctx;
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx, params);
+
+        ok = dh_pem_priv(ctx->provctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_pem_priv(void *vctx, void *dh, BIO *out,
+                        OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    struct dh_priv_ctx_st *ctx = vctx;
+    int ret;
+
+    ctx->sc.cb = cb;
+    ctx->sc.cbarg = cbarg;
+
+    ret = ossl_prov_write_priv_pem_from_obj(out, dh, EVP_PKEY_DH,
+                                            ossl_prov_prepare_dh_params,
+                                            ossl_prov_dh_priv_to_der,
+                                            &ctx->sc);
+
+    return ret;
+}
+
+/*
+ * There's no specific print context, so we use the provider context
+ */
+static void *dh_print_newctx(void *provctx)
+{
+    return provctx;
+}
+
+static void dh_print_freectx(void *ctx)
+{
+}
+
+static int dh_priv_print_data(void *provctx, const OSSL_PARAM params[],
+                               BIO *out,
+                               OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(provctx, params); /* ctx == provctx */
+
+        ok = dh_priv_print(provctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_priv_print(void *ctx, void *dh, BIO *out,
+                          OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    return ossl_prov_print_dh(out, dh, dh_print_priv);
+}
+
+const OSSL_DISPATCH dh_priv_der_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_priv_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_priv_freectx },
+    { OSSL_FUNC_SERIALIZER_SET_CTX_PARAMS,
+      (void (*)(void))dh_priv_set_ctx_params },
+    { OSSL_FUNC_SERIALIZER_SETTABLE_CTX_PARAMS,
+      (void (*)(void))dh_priv_settable_ctx_params },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA, (void (*)(void))dh_priv_der_data },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_priv_der },
+    { 0, NULL }
+};
+
+const OSSL_DISPATCH dh_priv_pem_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_priv_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_priv_freectx },
+    { OSSL_FUNC_SERIALIZER_SET_CTX_PARAMS,
+      (void (*)(void))dh_priv_set_ctx_params },
+    { OSSL_FUNC_SERIALIZER_SETTABLE_CTX_PARAMS,
+      (void (*)(void))dh_priv_settable_ctx_params },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA, (void (*)(void))dh_pem_priv_data },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_pem_priv },
+    { 0, NULL }
+};
+
+const OSSL_DISPATCH dh_priv_text_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_print_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_print_freectx },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_priv_print },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA,
+      (void (*)(void))dh_priv_print_data },
+    { 0, NULL }
+};
diff --git a/providers/implementations/serializers/serializer_dh_pub.c b/providers/implementations/serializers/serializer_dh_pub.c
new file mode 100644
index 0000000000..73095c8fd1
--- /dev/null
+++ b/providers/implementations/serializers/serializer_dh_pub.c
@@ -0,0 +1,140 @@
+/*
+ * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/core_numbers.h>
+#include <openssl/err.h>
+#include <openssl/pem.h>
+#include <openssl/dh.h>
+#include <openssl/types.h>
+#include <openssl/params.h>
+#include "prov/bio.h"
+#include "prov/implementations.h"
+#include "serializer_local.h"
+
+static OSSL_OP_serializer_newctx_fn dh_pub_newctx;
+static OSSL_OP_serializer_freectx_fn dh_pub_freectx;
+static OSSL_OP_serializer_serialize_data_fn dh_pub_der_data;
+static OSSL_OP_serializer_serialize_object_fn dh_pub_der;
+static OSSL_OP_serializer_serialize_data_fn dh_pub_pem_data;
+static OSSL_OP_serializer_serialize_object_fn dh_pub_pem;
+
+static OSSL_OP_serializer_serialize_data_fn dh_pub_print_data;
+static OSSL_OP_serializer_serialize_object_fn dh_pub_print;
+
+/* Public key : context */
+
+/*
+ * There's no specific implementation context, so we use the provider context
+ */
+static void *dh_pub_newctx(void *provctx)
+{
+    return provctx;
+}
+
+static void dh_pub_freectx(void *ctx)
+{
+}
+
+/* Public key : DER */
+static int dh_pub_der_data(void *ctx, const OSSL_PARAM params[], BIO *out,
+                            OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx, params); /* ctx == provctx */
+
+        ok = dh_pub_der(ctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_pub_der(void *ctx, void *dh, BIO *out,
+                       OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    return ossl_prov_write_pub_der_from_obj(out, dh, EVP_PKEY_DH,
+                                            ossl_prov_prepare_dh_params,
+                                            ossl_prov_dh_pub_to_der);
+}
+
+/* Public key : PEM */
+static int dh_pub_pem_data(void *ctx, const OSSL_PARAM params[], BIO *out,
+                            OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx, params); /* ctx == provctx */
+
+        ok = dh_pub_pem(ctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_pub_pem(void *ctx, void *dh, BIO *out,
+                       OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    return ossl_prov_write_pub_pem_from_obj(out, dh, EVP_PKEY_DH,
+                                            ossl_prov_prepare_dh_params,
+                                            ossl_prov_dh_pub_to_der);
+
+}
+
+static int dh_pub_print_data(void *ctx, const OSSL_PARAM params[], BIO *out,
+                              OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    OSSL_OP_keymgmt_importkey_fn *dh_importkey =
+        ossl_prov_get_dh_importkey();
+    int ok = 0;
+
+    if (dh_importkey != NULL) {
+        DH *dh = dh_importkey(ctx, params); /* ctx == provctx */
+
+        ok = dh_pub_print(ctx, dh, out, cb, cbarg);
+        DH_free(dh);
+    }
+    return ok;
+}
+
+static int dh_pub_print(void *ctx, void *dh, BIO *out,
+                         OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
+{
+    return ossl_prov_print_dh(out, dh, 0);
+}
+
+const OSSL_DISPATCH dh_pub_der_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_pub_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_pub_freectx },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA, (void (*)(void))dh_pub_der_data },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_pub_der },
+    { 0, NULL }
+};
+
+const OSSL_DISPATCH dh_pub_pem_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_pub_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_pub_freectx },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA, (void (*)(void))dh_pub_pem_data },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_pub_pem },
+    { 0, NULL }
+};
+
+const OSSL_DISPATCH dh_pub_text_serializer_functions[] = {
+    { OSSL_FUNC_SERIALIZER_NEWCTX, (void (*)(void))dh_pub_newctx },
+    { OSSL_FUNC_SERIALIZER_FREECTX, (void (*)(void))dh_pub_freectx },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_OBJECT, (void (*)(void))dh_pub_print },
+    { OSSL_FUNC_SERIALIZER_SERIALIZE_DATA,
+      (void (*)(void))dh_pub_print_data },
+    { 0, NULL }
+};
diff --git a/providers/implementations/serializers/serializer_local.h b/providers/implementations/serializers/serializer_local.h
index 47d025c0c3..c9135eb197 100644
--- a/providers/implementations/serializers/serializer_local.h
+++ b/providers/implementations/serializers/serializer_local.h
@@ -33,11 +33,25 @@ struct pkcs8_encrypt_ctx_st {
 OSSL_OP_keymgmt_importkey_fn *ossl_prov_get_importkey(const OSSL_DISPATCH *fns);
 
 OSSL_OP_keymgmt_importkey_fn *ossl_prov_get_rsa_importkey(void);
+OSSL_OP_keymgmt_importkey_fn *ossl_prov_get_dh_importkey(void);
+
+int ossl_prov_prepare_dh_params(const void *dh, int nid,
+                                ASN1_STRING **pstr, int *pstrtype);
+int ossl_prov_dh_pub_to_der(const void *dh, unsigned char **pder);
+int ossl_prov_dh_priv_to_der(const void *dh, unsigned char **pder);
 
 int ossl_prov_print_labeled_bignum(BIO *out, const char *label,
                                    const BIGNUM *n);
 int ossl_prov_print_rsa(BIO *out, RSA *rsa, int priv);
 
+enum dh_print_type {
+    dh_print_priv,
+    dh_print_pub,
+    dh_print_params
+};
+
+int ossl_prov_print_dh(BIO *out, DH *dh, enum dh_print_type type);
+
 int ossl_prov_write_priv_der_from_obj(BIO *out, const void *obj, int obj_nid,
                                       int (*p2s)(const void *obj, int nid,
                                                  ASN1_STRING **str,