[thirdparty/openssl.git] / crypto / cms / cms_ec.c

/*
 * Copyright 2006-2022 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 <assert.h>
#include <openssl/cms.h>
#include <openssl/err.h>
#include <openssl/decoder.h>
#include "internal/sizes.h"
#include "crypto/asn1.h"
#include "crypto/evp.h"
#include "cms_local.h"

static EVP_PKEY *pkey_type2param(int ptype, const void *pval,
                                 OSSL_LIB_CTX *libctx, const char *propq)
{
    EVP_PKEY *pkey = NULL;
    EVP_PKEY_CTX *pctx = NULL;
    OSSL_DECODER_CTX *ctx = NULL;

    if (ptype == V_ASN1_SEQUENCE) {
        const ASN1_STRING *pstr = pval;
        const unsigned char *pm = pstr->data;
        size_t pmlen = (size_t)pstr->length;
        int selection = OSSL_KEYMGMT_SELECT_ALL_PARAMETERS;

        ctx = OSSL_DECODER_CTX_new_for_pkey(&pkey, "DER", NULL, "EC",
                                            selection, libctx, propq);
        if (ctx == NULL)
            goto err;

        if (!OSSL_DECODER_from_data(ctx, &pm, &pmlen)) {
            ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
            goto err;
        }
        OSSL_DECODER_CTX_free(ctx);
        return pkey;
    } else if (ptype == V_ASN1_OBJECT) {
        const ASN1_OBJECT *poid = pval;
        char groupname[OSSL_MAX_NAME_SIZE];

        /* type == V_ASN1_OBJECT => the parameters are given by an asn1 OID */
        pctx = EVP_PKEY_CTX_new_from_name(libctx, "EC", propq);
        if (pctx == NULL || EVP_PKEY_paramgen_init(pctx) <= 0)
            goto err;
        if (OBJ_obj2txt(groupname, sizeof(groupname), poid, 0) <= 0
                || EVP_PKEY_CTX_set_group_name(pctx, groupname) <= 0) {
            ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
            goto err;
        }
        if (EVP_PKEY_paramgen(pctx, &pkey) <= 0)
            goto err;
        EVP_PKEY_CTX_free(pctx);
        return pkey;
    }

    ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
    return NULL;

 err:
    EVP_PKEY_free(pkey);
    EVP_PKEY_CTX_free(pctx);
    OSSL_DECODER_CTX_free(ctx);
    return NULL;
}

static int ecdh_cms_set_peerkey(EVP_PKEY_CTX *pctx,
                                X509_ALGOR *alg, ASN1_BIT_STRING *pubkey)
{
    const ASN1_OBJECT *aoid;
    int atype;
    const void *aval;
    int rv = 0;
    EVP_PKEY *pkpeer = NULL;
    const unsigned char *p;
    int plen;

    X509_ALGOR_get0(&aoid, &atype, &aval, alg);
    if (OBJ_obj2nid(aoid) != NID_X9_62_id_ecPublicKey)
        goto err;

    /* If absent parameters get group from main key */
    if (atype == V_ASN1_UNDEF || atype == V_ASN1_NULL) {
        EVP_PKEY *pk;

        pk = EVP_PKEY_CTX_get0_pkey(pctx);
        if (pk == NULL)
            goto err;

        pkpeer = EVP_PKEY_new();
        if (pkpeer == NULL)
            goto err;
        if (!EVP_PKEY_copy_parameters(pkpeer, pk))
            goto err;
    } else {
        pkpeer = pkey_type2param(atype, aval,
                                 EVP_PKEY_CTX_get0_libctx(pctx),
                                 EVP_PKEY_CTX_get0_propq(pctx));
        if (pkpeer == NULL)
            goto err;
    }
    /* We have parameters now set public key */
    plen = ASN1_STRING_length(pubkey);
    p = ASN1_STRING_get0_data(pubkey);
    if (p == NULL || plen == 0)
        goto err;

    if (!EVP_PKEY_set1_encoded_public_key(pkpeer, p, plen))
        goto err;

    if (EVP_PKEY_derive_set_peer(pctx, pkpeer) > 0)
        rv = 1;
 err:
    EVP_PKEY_free(pkpeer);
    return rv;
}

/* Set KDF parameters based on KDF NID */
static int ecdh_cms_set_kdf_param(EVP_PKEY_CTX *pctx, int eckdf_nid)
{
    int kdf_nid, kdfmd_nid, cofactor;
    const EVP_MD *kdf_md;

    if (eckdf_nid == NID_undef)
        return 0;

    /* Lookup KDF type, cofactor mode and digest */
    if (!OBJ_find_sigid_algs(eckdf_nid, &kdfmd_nid, &kdf_nid))
        return 0;

    if (kdf_nid == NID_dh_std_kdf)
        cofactor = 0;
    else if (kdf_nid == NID_dh_cofactor_kdf)
        cofactor = 1;
    else
        return 0;

    if (EVP_PKEY_CTX_set_ecdh_cofactor_mode(pctx, cofactor) <= 0)
        return 0;

    if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, EVP_PKEY_ECDH_KDF_X9_63) <= 0)
        return 0;

    kdf_md = EVP_get_digestbynid(kdfmd_nid);
    if (!kdf_md)
        return 0;

    if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
        return 0;
    return 1;
}

static int ecdh_cms_set_shared_info(EVP_PKEY_CTX *pctx, CMS_RecipientInfo *ri)
{
    int rv = 0;
    X509_ALGOR *alg, *kekalg = NULL;
    ASN1_OCTET_STRING *ukm;
    const unsigned char *p;
    unsigned char *der = NULL;
    int plen, keylen;
    EVP_CIPHER *kekcipher = NULL;
    EVP_CIPHER_CTX *kekctx;
    char name[OSSL_MAX_NAME_SIZE];

    if (!CMS_RecipientInfo_kari_get0_alg(ri, &alg, &ukm))
        return 0;

    if (!ecdh_cms_set_kdf_param(pctx, OBJ_obj2nid(alg->algorithm))) {
        ERR_raise(ERR_LIB_CMS, CMS_R_KDF_PARAMETER_ERROR);
        return 0;
    }

    if (alg->parameter->type != V_ASN1_SEQUENCE)
        return 0;

    p = alg->parameter->value.sequence->data;
    plen = alg->parameter->value.sequence->length;
    kekalg = d2i_X509_ALGOR(NULL, &p, plen);
    if (kekalg == NULL)
        goto err;
    kekctx = CMS_RecipientInfo_kari_get0_ctx(ri);
    if (kekctx == NULL)
        goto err;
    OBJ_obj2txt(name, sizeof(name), kekalg->algorithm, 0);
    kekcipher = EVP_CIPHER_fetch(pctx->libctx, name, pctx->propquery);
    if (kekcipher == NULL || EVP_CIPHER_get_mode(kekcipher) != EVP_CIPH_WRAP_MODE)
        goto err;
    if (!EVP_EncryptInit_ex(kekctx, kekcipher, NULL, NULL, NULL))
        goto err;
    if (EVP_CIPHER_asn1_to_param(kekctx, kekalg->parameter) <= 0)
        goto err;

    keylen = EVP_CIPHER_CTX_get_key_length(kekctx);
    if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
        goto err;

    plen = CMS_SharedInfo_encode(&der, kekalg, ukm, keylen);

    if (plen <= 0)
        goto err;

    if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, der, plen) <= 0)
        goto err;
    der = NULL;

    rv = 1;
 err:
    EVP_CIPHER_free(kekcipher);
    X509_ALGOR_free(kekalg);
    OPENSSL_free(der);
    return rv;
}

static int ecdh_cms_decrypt(CMS_RecipientInfo *ri)
{
    EVP_PKEY_CTX *pctx;

    pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
    if (pctx == NULL)
        return 0;
    /* See if we need to set peer key */
    if (!EVP_PKEY_CTX_get0_peerkey(pctx)) {
        X509_ALGOR *alg;
        ASN1_BIT_STRING *pubkey;

        if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &alg, &pubkey,
                                                 NULL, NULL, NULL))
            return 0;
        if (alg == NULL || pubkey == NULL)
            return 0;
        if (!ecdh_cms_set_peerkey(pctx, alg, pubkey)) {
            ERR_raise(ERR_LIB_CMS, CMS_R_PEER_KEY_ERROR);
            return 0;
        }
    }
    /* Set ECDH derivation parameters and initialise unwrap context */
    if (!ecdh_cms_set_shared_info(pctx, ri)) {
        ERR_raise(ERR_LIB_CMS, CMS_R_SHARED_INFO_ERROR);
        return 0;
    }
    return 1;
}

static int ecdh_cms_encrypt(CMS_RecipientInfo *ri)
{
    EVP_PKEY_CTX *pctx;
    EVP_PKEY *pkey;
    EVP_CIPHER_CTX *ctx;
    int keylen;
    X509_ALGOR *talg, *wrap_alg = NULL;
    const ASN1_OBJECT *aoid;
    ASN1_BIT_STRING *pubkey;
    ASN1_STRING *wrap_str;
    ASN1_OCTET_STRING *ukm;
    unsigned char *penc = NULL;
    size_t penclen;
    int rv = 0;
    int ecdh_nid, kdf_type, kdf_nid, wrap_nid;
    const EVP_MD *kdf_md;

    pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
    if (pctx == NULL)
        return 0;
    /* Get ephemeral key */
    pkey = EVP_PKEY_CTX_get0_pkey(pctx);
    if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &talg, &pubkey,
                                             NULL, NULL, NULL))
        goto err;
    X509_ALGOR_get0(&aoid, NULL, NULL, talg);
    /* Is everything uninitialised? */
    if (aoid == OBJ_nid2obj(NID_undef)) {
        /* Set the key */

        penclen = EVP_PKEY_get1_encoded_public_key(pkey, &penc);
        ASN1_STRING_set0(pubkey, penc, penclen);
        ossl_asn1_string_set_bits_left(pubkey, 0);

        penc = NULL;
        (void)X509_ALGOR_set0(talg, OBJ_nid2obj(NID_X9_62_id_ecPublicKey),
                              V_ASN1_UNDEF, NULL); /* cannot fail */
    }

    /* See if custom parameters set */
    kdf_type = EVP_PKEY_CTX_get_ecdh_kdf_type(pctx);
    if (kdf_type <= 0)
        goto err;
    if (EVP_PKEY_CTX_get_ecdh_kdf_md(pctx, &kdf_md) <= 0)
        goto err;
    ecdh_nid = EVP_PKEY_CTX_get_ecdh_cofactor_mode(pctx);
    if (ecdh_nid < 0)
        goto err;
    else if (ecdh_nid == 0)
        ecdh_nid = NID_dh_std_kdf;
    else if (ecdh_nid == 1)
        ecdh_nid = NID_dh_cofactor_kdf;

    if (kdf_type == EVP_PKEY_ECDH_KDF_NONE) {
        kdf_type = EVP_PKEY_ECDH_KDF_X9_63;
        if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, kdf_type) <= 0)
            goto err;
    } else
        /* Unknown KDF */
        goto err;
    if (kdf_md == NULL) {
        /* Fixme later for better MD */
        kdf_md = EVP_sha1();
        if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
            goto err;
    }

    if (!CMS_RecipientInfo_kari_get0_alg(ri, &talg, &ukm))
        goto err;

    /* Lookup NID for KDF+cofactor+digest */

    if (!OBJ_find_sigid_by_algs(&kdf_nid, EVP_MD_get_type(kdf_md), ecdh_nid))
        goto err;
    /* Get wrap NID */
    ctx = CMS_RecipientInfo_kari_get0_ctx(ri);
    wrap_nid = EVP_CIPHER_CTX_get_type(ctx);
    keylen = EVP_CIPHER_CTX_get_key_length(ctx);

    /* Package wrap algorithm in an AlgorithmIdentifier */

    wrap_alg = X509_ALGOR_new();
    if (wrap_alg == NULL)
        goto err;
    wrap_alg->algorithm = OBJ_nid2obj(wrap_nid);
    wrap_alg->parameter = ASN1_TYPE_new();
    if (wrap_alg->parameter == NULL)
        goto err;
    if (EVP_CIPHER_param_to_asn1(ctx, wrap_alg->parameter) <= 0)
        goto err;
    if (ASN1_TYPE_get(wrap_alg->parameter) == NID_undef) {
        ASN1_TYPE_free(wrap_alg->parameter);
        wrap_alg->parameter = NULL;
    }

    if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
        goto err;

    penclen = CMS_SharedInfo_encode(&penc, wrap_alg, ukm, keylen);

    if (penclen == 0)
        goto err;

    if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, penc, penclen) <= 0)
        goto err;
    penc = NULL;

    /*
     * Now need to wrap encoding of wrap AlgorithmIdentifier into parameter
     * of another AlgorithmIdentifier.
     */
    penclen = i2d_X509_ALGOR(wrap_alg, &penc);
    if (penc == NULL || penclen == 0)
        goto err;
    wrap_str = ASN1_STRING_new();
    if (wrap_str == NULL)
        goto err;
    ASN1_STRING_set0(wrap_str, penc, penclen);
    penc = NULL;
    rv = X509_ALGOR_set0(talg, OBJ_nid2obj(kdf_nid), V_ASN1_SEQUENCE, wrap_str);
    if (!rv)
        ASN1_STRING_free(wrap_str);

 err:
    OPENSSL_free(penc);
    X509_ALGOR_free(wrap_alg);
    return rv;
}

int ossl_cms_ecdh_envelope(CMS_RecipientInfo *ri, int decrypt)
{
    assert(decrypt == 0 || decrypt == 1);

    if (decrypt == 1)
        return ecdh_cms_decrypt(ri);

    if (decrypt == 0)
        return ecdh_cms_encrypt(ri);

    ERR_raise(ERR_LIB_CMS, CMS_R_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
    return 0;
}
Commit	Line	Data
0b3a4ef2	1	/*
fecb3aae	2	* Copyright 2006-2022 The OpenSSL Project Authors. All Rights Reserved.
0b3a4ef2 MC	3	*
	4	* Licensed under the Apache License 2.0 (the "License"). You may not use
	5	* this file except in compliance with the License. You can obtain a copy
	6	* in the file LICENSE in the source distribution or at
	7	* https://www.openssl.org/source/license.html
	8	*/
	9
9ab7fe48	10	#include <assert.h>
0b3a4ef2 MC	11	#include <openssl/cms.h>
	12	#include <openssl/err.h>
	13	#include <openssl/decoder.h>
ad57a13b	14	#include "internal/sizes.h"
7c310e87	15	#include "crypto/asn1.h"
0b3a4ef2	16	#include "crypto/evp.h"
ad57a13b	17	#include "cms_local.h"
0b3a4ef2	18
0b3a4ef2	19	static EVP_PKEY pkey_type2param(int ptype, const void pval,
b4250010	20	OSSL_LIB_CTX libctx, const char propq)
0b3a4ef2 MC	21	{
	22	EVP_PKEY *pkey = NULL;
	23	EVP_PKEY_CTX *pctx = NULL;
8dff167d	24	OSSL_DECODER_CTX *ctx = NULL;
0b3a4ef2 MC	25
	26	if (ptype == V_ASN1_SEQUENCE) {
	27	const ASN1_STRING *pstr = pval;
	28	const unsigned char *pm = pstr->data;
4f2abe43	29	size_t pmlen = (size_t)pstr->length;
4f2abe43	30	int selection = OSSL_KEYMGMT_SELECT_ALL_PARAMETERS;
0b3a4ef2	31
fe75766c TM	32	ctx = OSSL_DECODER_CTX_new_for_pkey(&pkey, "DER", NULL, "EC",
fe75766c TM	33	selection, libctx, propq);
9ab7fe48 MC	34	if (ctx == NULL)
	35	goto err;
	36
8dff167d P	37	if (!OSSL_DECODER_from_data(ctx, &pm, &pmlen)) {
	38	ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
	39	goto err;
60d13c8f	40	}
0b3a4ef2	41	OSSL_DECODER_CTX_free(ctx);
dfb0b8d6	42	return pkey;
0b3a4ef2 MC	43	} else if (ptype == V_ASN1_OBJECT) {
0b3a4ef2 MC	44	const ASN1_OBJECT *poid = pval;
ad57a13b	45	char groupname[OSSL_MAX_NAME_SIZE];
0b3a4ef2	46
9ab7fe48	47	/* type == V_ASN1_OBJECT => the parameters are given by an asn1 OID */
0b3a4ef2	48	pctx = EVP_PKEY_CTX_new_from_name(libctx, "EC", propq);
9ab7fe48	49	if (pctx == NULL \|\| EVP_PKEY_paramgen_init(pctx) <= 0)
0b3a4ef2	50	goto err;
2349d7ba	51	if (OBJ_obj2txt(groupname, sizeof(groupname), poid, 0) <= 0
56876ae9	52	\|\| EVP_PKEY_CTX_set_group_name(pctx, groupname) <= 0) {
9311d0c4	53	ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
0b3a4ef2 MC	54	goto err;
0b3a4ef2 MC	55	}
9ab7fe48 MC	56	if (EVP_PKEY_paramgen(pctx, &pkey) <= 0)
9ab7fe48 MC	57	goto err;
dfb0b8d6 P	58	EVP_PKEY_CTX_free(pctx);
dfb0b8d6 P	59	return pkey;
0b3a4ef2 MC	60	}
0b3a4ef2 MC	61
dfb0b8d6 P	62	ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
dfb0b8d6 P	63	return NULL;
0b3a4ef2 MC	64
	65	err:
	66	EVP_PKEY_free(pkey);
	67	EVP_PKEY_CTX_free(pctx);
8dff167d	68	OSSL_DECODER_CTX_free(ctx);
0b3a4ef2 MC	69	return NULL;
	70	}
	71
	72	static int ecdh_cms_set_peerkey(EVP_PKEY_CTX *pctx,
	73	X509_ALGOR alg, ASN1_BIT_STRING pubkey)
	74	{
	75	const ASN1_OBJECT *aoid;
	76	int atype;
	77	const void *aval;
	78	int rv = 0;
	79	EVP_PKEY *pkpeer = NULL;
	80	const unsigned char *p;
	81	int plen;
	82
	83	X509_ALGOR_get0(&aoid, &atype, &aval, alg);
	84	if (OBJ_obj2nid(aoid) != NID_X9_62_id_ecPublicKey)
	85	goto err;
9ab7fe48	86
0b3a4ef2 MC	87	/* If absent parameters get group from main key */
	88	if (atype == V_ASN1_UNDEF \|\| atype == V_ASN1_NULL) {
	89	EVP_PKEY *pk;
9ab7fe48	90
0b3a4ef2 MC	91	pk = EVP_PKEY_CTX_get0_pkey(pctx);
	92	if (pk == NULL)
	93	goto err;
	94
	95	pkpeer = EVP_PKEY_new();
	96	if (pkpeer == NULL)
	97	goto err;
	98	if (!EVP_PKEY_copy_parameters(pkpeer, pk))
	99	goto err;
	100	} else {
0b3a4ef2	101	pkpeer = pkey_type2param(atype, aval,
29000e43 MC	102	EVP_PKEY_CTX_get0_libctx(pctx),
29000e43 MC	103	EVP_PKEY_CTX_get0_propq(pctx));
0b3a4ef2 MC	104	if (pkpeer == NULL)
	105	goto err;
	106	}
	107	/* We have parameters now set public key */
	108	plen = ASN1_STRING_length(pubkey);
	109	p = ASN1_STRING_get0_data(pubkey);
	110	if (p == NULL \|\| plen == 0)
	111	goto err;
	112
5ac8fb58	113	if (!EVP_PKEY_set1_encoded_public_key(pkpeer, p, plen))
0b3a4ef2 MC	114	goto err;
	115
	116	if (EVP_PKEY_derive_set_peer(pctx, pkpeer) > 0)
	117	rv = 1;
	118	err:
	119	EVP_PKEY_free(pkpeer);
	120	return rv;
	121	}
	122
	123	/* Set KDF parameters based on KDF NID */
	124	static int ecdh_cms_set_kdf_param(EVP_PKEY_CTX *pctx, int eckdf_nid)
	125	{
	126	int kdf_nid, kdfmd_nid, cofactor;
	127	const EVP_MD *kdf_md;
9ab7fe48	128
0b3a4ef2 MC	129	if (eckdf_nid == NID_undef)
	130	return 0;
	131
	132	/* Lookup KDF type, cofactor mode and digest */
	133	if (!OBJ_find_sigid_algs(eckdf_nid, &kdfmd_nid, &kdf_nid))
	134	return 0;
	135
	136	if (kdf_nid == NID_dh_std_kdf)
	137	cofactor = 0;
	138	else if (kdf_nid == NID_dh_cofactor_kdf)
	139	cofactor = 1;
	140	else
	141	return 0;
	142
	143	if (EVP_PKEY_CTX_set_ecdh_cofactor_mode(pctx, cofactor) <= 0)
	144	return 0;
	145
	146	if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, EVP_PKEY_ECDH_KDF_X9_63) <= 0)
	147	return 0;
	148
	149	kdf_md = EVP_get_digestbynid(kdfmd_nid);
	150	if (!kdf_md)
	151	return 0;
	152
	153	if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
	154	return 0;
	155	return 1;
	156	}
	157
	158	static int ecdh_cms_set_shared_info(EVP_PKEY_CTX pctx, CMS_RecipientInfo ri)
	159	{
	160	int rv = 0;
0b3a4ef2 MC	161	X509_ALGOR alg, kekalg = NULL;
	162	ASN1_OCTET_STRING *ukm;
	163	const unsigned char *p;
	164	unsigned char *der = NULL;
	165	int plen, keylen;
	166	EVP_CIPHER *kekcipher = NULL;
	167	EVP_CIPHER_CTX *kekctx;
ad57a13b	168	char name[OSSL_MAX_NAME_SIZE];
0b3a4ef2 MC	169
	170	if (!CMS_RecipientInfo_kari_get0_alg(ri, &alg, &ukm))
	171	return 0;
	172
	173	if (!ecdh_cms_set_kdf_param(pctx, OBJ_obj2nid(alg->algorithm))) {
9311d0c4	174	ERR_raise(ERR_LIB_CMS, CMS_R_KDF_PARAMETER_ERROR);
0b3a4ef2 MC	175	return 0;
	176	}
	177
	178	if (alg->parameter->type != V_ASN1_SEQUENCE)
	179	return 0;
	180
	181	p = alg->parameter->value.sequence->data;
	182	plen = alg->parameter->value.sequence->length;
	183	kekalg = d2i_X509_ALGOR(NULL, &p, plen);
	184	if (kekalg == NULL)
	185	goto err;
	186	kekctx = CMS_RecipientInfo_kari_get0_ctx(ri);
	187	if (kekctx == NULL)
	188	goto err;
ad57a13b	189	OBJ_obj2txt(name, sizeof(name), kekalg->algorithm, 0);
0b3a4ef2	190	kekcipher = EVP_CIPHER_fetch(pctx->libctx, name, pctx->propquery);
ed576acd	191	if (kekcipher == NULL \|\| EVP_CIPHER_get_mode(kekcipher) != EVP_CIPH_WRAP_MODE)
0b3a4ef2 MC	192	goto err;
	193	if (!EVP_EncryptInit_ex(kekctx, kekcipher, NULL, NULL, NULL))
	194	goto err;
	195	if (EVP_CIPHER_asn1_to_param(kekctx, kekalg->parameter) <= 0)
	196	goto err;
	197
ed576acd	198	keylen = EVP_CIPHER_CTX_get_key_length(kekctx);
0b3a4ef2 MC	199	if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
	200	goto err;
	201
	202	plen = CMS_SharedInfo_encode(&der, kekalg, ukm, keylen);
	203
	204	if (plen <= 0)
	205	goto err;
	206
	207	if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, der, plen) <= 0)
	208	goto err;
	209	der = NULL;
	210
	211	rv = 1;
	212	err:
	213	EVP_CIPHER_free(kekcipher);
	214	X509_ALGOR_free(kekalg);
	215	OPENSSL_free(der);
	216	return rv;
	217	}
	218
	219	static int ecdh_cms_decrypt(CMS_RecipientInfo *ri)
	220	{
	221	EVP_PKEY_CTX *pctx;
	222
	223	pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
	224	if (pctx == NULL)
	225	return 0;
	226	/* See if we need to set peer key */
	227	if (!EVP_PKEY_CTX_get0_peerkey(pctx)) {
	228	X509_ALGOR *alg;
	229	ASN1_BIT_STRING *pubkey;
	230
	231	if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &alg, &pubkey,
	232	NULL, NULL, NULL))
	233	return 0;
9ab7fe48	234	if (alg == NULL \|\| pubkey == NULL)
0b3a4ef2 MC	235	return 0;
0b3a4ef2 MC	236	if (!ecdh_cms_set_peerkey(pctx, alg, pubkey)) {
9311d0c4	237	ERR_raise(ERR_LIB_CMS, CMS_R_PEER_KEY_ERROR);
0b3a4ef2 MC	238	return 0;
	239	}
	240	}
	241	/* Set ECDH derivation parameters and initialise unwrap context */
	242	if (!ecdh_cms_set_shared_info(pctx, ri)) {
9311d0c4	243	ERR_raise(ERR_LIB_CMS, CMS_R_SHARED_INFO_ERROR);
0b3a4ef2 MC	244	return 0;
	245	}
	246	return 1;
	247	}
	248
	249	static int ecdh_cms_encrypt(CMS_RecipientInfo *ri)
	250	{
	251	EVP_PKEY_CTX *pctx;
	252	EVP_PKEY *pkey;
	253	EVP_CIPHER_CTX *ctx;
	254	int keylen;
	255	X509_ALGOR talg, wrap_alg = NULL;
	256	const ASN1_OBJECT *aoid;
	257	ASN1_BIT_STRING *pubkey;
	258	ASN1_STRING *wrap_str;
	259	ASN1_OCTET_STRING *ukm;
	260	unsigned char *penc = NULL;
	261	size_t penclen;
	262	int rv = 0;
	263	int ecdh_nid, kdf_type, kdf_nid, wrap_nid;
	264	const EVP_MD *kdf_md;
	265
	266	pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
	267	if (pctx == NULL)
	268	return 0;
	269	/* Get ephemeral key */
	270	pkey = EVP_PKEY_CTX_get0_pkey(pctx);
	271	if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &talg, &pubkey,
	272	NULL, NULL, NULL))
	273	goto err;
	274	X509_ALGOR_get0(&aoid, NULL, NULL, talg);
	275	/* Is everything uninitialised? */
	276	if (aoid == OBJ_nid2obj(NID_undef)) {
	277	/* Set the key */
	278
5ac8fb58	279	penclen = EVP_PKEY_get1_encoded_public_key(pkey, &penc);
0b3a4ef2	280	ASN1_STRING_set0(pubkey, penc, penclen);
7c310e87	281	ossl_asn1_string_set_bits_left(pubkey, 0);
0b3a4ef2 MC	282
0b3a4ef2 MC	283	penc = NULL;
04bc3c12 DDO	284	(void)X509_ALGOR_set0(talg, OBJ_nid2obj(NID_X9_62_id_ecPublicKey),
04bc3c12 DDO	285	V_ASN1_UNDEF, NULL); /* cannot fail */
0b3a4ef2 MC	286	}
	287
	288	/* See if custom parameters set */
	289	kdf_type = EVP_PKEY_CTX_get_ecdh_kdf_type(pctx);
	290	if (kdf_type <= 0)
	291	goto err;
2cba2e16	292	if (EVP_PKEY_CTX_get_ecdh_kdf_md(pctx, &kdf_md) <= 0)
0b3a4ef2 MC	293	goto err;
	294	ecdh_nid = EVP_PKEY_CTX_get_ecdh_cofactor_mode(pctx);
	295	if (ecdh_nid < 0)
	296	goto err;
	297	else if (ecdh_nid == 0)
	298	ecdh_nid = NID_dh_std_kdf;
	299	else if (ecdh_nid == 1)
	300	ecdh_nid = NID_dh_cofactor_kdf;
	301
	302	if (kdf_type == EVP_PKEY_ECDH_KDF_NONE) {
	303	kdf_type = EVP_PKEY_ECDH_KDF_X9_63;
	304	if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, kdf_type) <= 0)
	305	goto err;
	306	} else
	307	/* Unknown KDF */
	308	goto err;
	309	if (kdf_md == NULL) {
	310	/* Fixme later for better MD */
	311	kdf_md = EVP_sha1();
	312	if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
	313	goto err;
	314	}
	315
	316	if (!CMS_RecipientInfo_kari_get0_alg(ri, &talg, &ukm))
	317	goto err;
	318
	319	/* Lookup NID for KDF+cofactor+digest */
	320
ed576acd	321	if (!OBJ_find_sigid_by_algs(&kdf_nid, EVP_MD_get_type(kdf_md), ecdh_nid))
0b3a4ef2 MC	322	goto err;
	323	/* Get wrap NID */
	324	ctx = CMS_RecipientInfo_kari_get0_ctx(ri);
ed576acd TM	325	wrap_nid = EVP_CIPHER_CTX_get_type(ctx);
ed576acd TM	326	keylen = EVP_CIPHER_CTX_get_key_length(ctx);
0b3a4ef2 MC	327
	328	/* Package wrap algorithm in an AlgorithmIdentifier */
	329
	330	wrap_alg = X509_ALGOR_new();
	331	if (wrap_alg == NULL)
	332	goto err;
	333	wrap_alg->algorithm = OBJ_nid2obj(wrap_nid);
	334	wrap_alg->parameter = ASN1_TYPE_new();
	335	if (wrap_alg->parameter == NULL)
	336	goto err;
	337	if (EVP_CIPHER_param_to_asn1(ctx, wrap_alg->parameter) <= 0)
	338	goto err;
	339	if (ASN1_TYPE_get(wrap_alg->parameter) == NID_undef) {
	340	ASN1_TYPE_free(wrap_alg->parameter);
	341	wrap_alg->parameter = NULL;
	342	}
	343
	344	if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
	345	goto err;
	346
	347	penclen = CMS_SharedInfo_encode(&penc, wrap_alg, ukm, keylen);
	348
9ab7fe48	349	if (penclen == 0)
0b3a4ef2 MC	350	goto err;
	351
	352	if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, penc, penclen) <= 0)
	353	goto err;
	354	penc = NULL;
	355
	356	/*
	357	* Now need to wrap encoding of wrap AlgorithmIdentifier into parameter
	358	* of another AlgorithmIdentifier.
	359	*/
	360	penclen = i2d_X509_ALGOR(wrap_alg, &penc);
9ab7fe48	361	if (penc == NULL \|\| penclen == 0)
0b3a4ef2 MC	362	goto err;
	363	wrap_str = ASN1_STRING_new();
	364	if (wrap_str == NULL)
	365	goto err;
	366	ASN1_STRING_set0(wrap_str, penc, penclen);
	367	penc = NULL;
04bc3c12 DDO	368	rv = X509_ALGOR_set0(talg, OBJ_nid2obj(kdf_nid), V_ASN1_SEQUENCE, wrap_str);
	369	if (!rv)
	370	ASN1_STRING_free(wrap_str);
0b3a4ef2 MC	371
	372	err:
	373	OPENSSL_free(penc);
	374	X509_ALGOR_free(wrap_alg);
	375	return rv;
	376	}
	377
53155f1c	378	int ossl_cms_ecdh_envelope(CMS_RecipientInfo *ri, int decrypt)
0b3a4ef2	379	{
9ab7fe48 MC	380	assert(decrypt == 0 \|\| decrypt == 1);
9ab7fe48 MC	381
0b3a4ef2 MC	382	if (decrypt == 1)
0b3a4ef2 MC	383	return ecdh_cms_decrypt(ri);
9ab7fe48 MC	384
9ab7fe48 MC	385	if (decrypt == 0)
0b3a4ef2 MC	386	return ecdh_cms_encrypt(ri);
0b3a4ef2 MC	387
9311d0c4	388	ERR_raise(ERR_LIB_CMS, CMS_R_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
0b3a4ef2	389	return 0;
9ab7fe48	390	}