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

/*
 * Copyright 2006-2021 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 "cms_local.h"
#include "crypto/evp.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;

    if (ptype == V_ASN1_SEQUENCE) {
        const ASN1_STRING *pstr = pval;
        const unsigned char *pm = pstr->data;
        size_t pmlen = (size_t)pstr->length;
        OSSL_DECODER_CTX *ctx = NULL;
        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;

        OSSL_DECODER_from_data(ctx, &pm, &pmlen);
        OSSL_DECODER_CTX_free(ctx);
    } else if (ptype == V_ASN1_OBJECT) {
        const ASN1_OBJECT *poid = pval;
        const char *groupname;

        /* 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;
        groupname = OBJ_nid2sn(OBJ_obj2nid(poid));
        if (groupname == NULL
                || !EVP_PKEY_CTX_set_group_name(pctx, groupname)) {
            ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
            goto err;
        }
        if (EVP_PKEY_paramgen(pctx, &pkey) <= 0)
            goto err;
    } else {
        ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
        goto err;
    }

    return pkey;

 err:
    EVP_PKEY_free(pkey);
    EVP_PKEY_CTX_free(pctx);
    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;
    const char *name;

    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;
    name = OBJ_nid2sn(OBJ_obj2nid(kekalg->algorithm));
    kekcipher = EVP_CIPHER_fetch(pctx->libctx, name, pctx->propquery);
    if (kekcipher == NULL || EVP_CIPHER_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_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);
        pubkey->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07);
        pubkey->flags |= ASN1_STRING_FLAG_BITS_LEFT;

        penc = NULL;
        X509_ALGOR_set0(talg, OBJ_nid2obj(NID_X9_62_id_ecPublicKey),
                        V_ASN1_UNDEF, NULL);
    }

    /* 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))
        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_type(kdf_md), ecdh_nid))
        goto err;
    /* Get wrap NID */
    ctx = CMS_RecipientInfo_kari_get0_ctx(ri);
    wrap_nid = EVP_CIPHER_CTX_type(ctx);
    keylen = EVP_CIPHER_CTX_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;
    X509_ALGOR_set0(talg, OBJ_nid2obj(kdf_nid), V_ASN1_SEQUENCE, wrap_str);

    rv = 1;

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

int 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;
}

/* ECDSA and DSA implementation is the same */
int cms_ecdsa_dsa_sign(CMS_SignerInfo *si, int verify)
{
    assert(verify == 0 || verify == 1);

    if (verify == 0) {
        int snid, hnid;
        X509_ALGOR *alg1, *alg2;
        EVP_PKEY *pkey = si->pkey;

        CMS_SignerInfo_get0_algs(si, NULL, NULL, &alg1, &alg2);
        if (alg1 == NULL || alg1->algorithm == NULL)
            return -1;
        hnid = OBJ_obj2nid(alg1->algorithm);
        if (hnid == NID_undef)
            return -1;
        if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
            return -1;
        X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
    }
    return 1;
}
Commit	Line	Data
0b3a4ef2	1	/*
a28d06f3	2	* Copyright 2006-2021 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>
	14	#include "cms_local.h"
	15	#include "crypto/evp.h"
	16
0b3a4ef2	17	static EVP_PKEY pkey_type2param(int ptype, const void pval,
b4250010	18	OSSL_LIB_CTX libctx, const char propq)
0b3a4ef2 MC	19	{
	20	EVP_PKEY *pkey = NULL;
	21	EVP_PKEY_CTX *pctx = NULL;
	22
	23	if (ptype == V_ASN1_SEQUENCE) {
	24	const ASN1_STRING *pstr = pval;
	25	const unsigned char *pm = pstr->data;
4f2abe43	26	size_t pmlen = (size_t)pstr->length;
0b3a4ef2	27	OSSL_DECODER_CTX *ctx = NULL;
4f2abe43	28	int selection = OSSL_KEYMGMT_SELECT_ALL_PARAMETERS;
0b3a4ef2	29
fe75766c TM	30	ctx = OSSL_DECODER_CTX_new_for_pkey(&pkey, "DER", NULL, "EC",
fe75766c TM	31	selection, libctx, propq);
9ab7fe48 MC	32	if (ctx == NULL)
	33	goto err;
	34
4f2abe43	35	OSSL_DECODER_from_data(ctx, &pm, &pmlen);
0b3a4ef2 MC	36	OSSL_DECODER_CTX_free(ctx);
	37	} else if (ptype == V_ASN1_OBJECT) {
	38	const ASN1_OBJECT *poid = pval;
	39	const char *groupname;
	40
9ab7fe48	41	/* type == V_ASN1_OBJECT => the parameters are given by an asn1 OID */
0b3a4ef2	42	pctx = EVP_PKEY_CTX_new_from_name(libctx, "EC", propq);
9ab7fe48	43	if (pctx == NULL \|\| EVP_PKEY_paramgen_init(pctx) <= 0)
0b3a4ef2 MC	44	goto err;
	45	groupname = OBJ_nid2sn(OBJ_obj2nid(poid));
	46	if (groupname == NULL
	47	\|\| !EVP_PKEY_CTX_set_group_name(pctx, groupname)) {
9311d0c4	48	ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
0b3a4ef2 MC	49	goto err;
0b3a4ef2 MC	50	}
9ab7fe48 MC	51	if (EVP_PKEY_paramgen(pctx, &pkey) <= 0)
9ab7fe48 MC	52	goto err;
0b3a4ef2	53	} else {
9311d0c4	54	ERR_raise(ERR_LIB_CMS, CMS_R_DECODE_ERROR);
0b3a4ef2 MC	55	goto err;
	56	}
	57
	58	return pkey;
	59
	60	err:
	61	EVP_PKEY_free(pkey);
	62	EVP_PKEY_CTX_free(pctx);
	63	return NULL;
	64	}
	65
	66	static int ecdh_cms_set_peerkey(EVP_PKEY_CTX *pctx,
	67	X509_ALGOR alg, ASN1_BIT_STRING pubkey)
	68	{
	69	const ASN1_OBJECT *aoid;
	70	int atype;
	71	const void *aval;
	72	int rv = 0;
	73	EVP_PKEY *pkpeer = NULL;
	74	const unsigned char *p;
	75	int plen;
	76
	77	X509_ALGOR_get0(&aoid, &atype, &aval, alg);
	78	if (OBJ_obj2nid(aoid) != NID_X9_62_id_ecPublicKey)
	79	goto err;
9ab7fe48	80
0b3a4ef2 MC	81	/* If absent parameters get group from main key */
	82	if (atype == V_ASN1_UNDEF \|\| atype == V_ASN1_NULL) {
	83	EVP_PKEY *pk;
9ab7fe48	84
0b3a4ef2 MC	85	pk = EVP_PKEY_CTX_get0_pkey(pctx);
	86	if (pk == NULL)
	87	goto err;
	88
	89	pkpeer = EVP_PKEY_new();
	90	if (pkpeer == NULL)
	91	goto err;
	92	if (!EVP_PKEY_copy_parameters(pkpeer, pk))
	93	goto err;
	94	} else {
0b3a4ef2	95	pkpeer = pkey_type2param(atype, aval,
29000e43 MC	96	EVP_PKEY_CTX_get0_libctx(pctx),
29000e43 MC	97	EVP_PKEY_CTX_get0_propq(pctx));
0b3a4ef2 MC	98	if (pkpeer == NULL)
	99	goto err;
	100	}
	101	/* We have parameters now set public key */
	102	plen = ASN1_STRING_length(pubkey);
	103	p = ASN1_STRING_get0_data(pubkey);
	104	if (p == NULL \|\| plen == 0)
	105	goto err;
	106
5ac8fb58	107	if (!EVP_PKEY_set1_encoded_public_key(pkpeer, p, plen))
0b3a4ef2 MC	108	goto err;
	109
	110	if (EVP_PKEY_derive_set_peer(pctx, pkpeer) > 0)
	111	rv = 1;
	112	err:
	113	EVP_PKEY_free(pkpeer);
	114	return rv;
	115	}
	116
	117	/* Set KDF parameters based on KDF NID */
	118	static int ecdh_cms_set_kdf_param(EVP_PKEY_CTX *pctx, int eckdf_nid)
	119	{
	120	int kdf_nid, kdfmd_nid, cofactor;
	121	const EVP_MD *kdf_md;
9ab7fe48	122
0b3a4ef2 MC	123	if (eckdf_nid == NID_undef)
	124	return 0;
	125
	126	/* Lookup KDF type, cofactor mode and digest */
	127	if (!OBJ_find_sigid_algs(eckdf_nid, &kdfmd_nid, &kdf_nid))
	128	return 0;
	129
	130	if (kdf_nid == NID_dh_std_kdf)
	131	cofactor = 0;
	132	else if (kdf_nid == NID_dh_cofactor_kdf)
	133	cofactor = 1;
	134	else
	135	return 0;
	136
	137	if (EVP_PKEY_CTX_set_ecdh_cofactor_mode(pctx, cofactor) <= 0)
	138	return 0;
	139
	140	if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, EVP_PKEY_ECDH_KDF_X9_63) <= 0)
	141	return 0;
	142
	143	kdf_md = EVP_get_digestbynid(kdfmd_nid);
	144	if (!kdf_md)
	145	return 0;
	146
	147	if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
	148	return 0;
	149	return 1;
	150	}
	151
	152	static int ecdh_cms_set_shared_info(EVP_PKEY_CTX pctx, CMS_RecipientInfo ri)
	153	{
	154	int rv = 0;
0b3a4ef2 MC	155	X509_ALGOR alg, kekalg = NULL;
	156	ASN1_OCTET_STRING *ukm;
	157	const unsigned char *p;
	158	unsigned char *der = NULL;
	159	int plen, keylen;
	160	EVP_CIPHER *kekcipher = NULL;
	161	EVP_CIPHER_CTX *kekctx;
	162	const char *name;
	163
	164	if (!CMS_RecipientInfo_kari_get0_alg(ri, &alg, &ukm))
	165	return 0;
	166
	167	if (!ecdh_cms_set_kdf_param(pctx, OBJ_obj2nid(alg->algorithm))) {
9311d0c4	168	ERR_raise(ERR_LIB_CMS, CMS_R_KDF_PARAMETER_ERROR);
0b3a4ef2 MC	169	return 0;
	170	}
	171
	172	if (alg->parameter->type != V_ASN1_SEQUENCE)
	173	return 0;
	174
	175	p = alg->parameter->value.sequence->data;
	176	plen = alg->parameter->value.sequence->length;
	177	kekalg = d2i_X509_ALGOR(NULL, &p, plen);
	178	if (kekalg == NULL)
	179	goto err;
	180	kekctx = CMS_RecipientInfo_kari_get0_ctx(ri);
	181	if (kekctx == NULL)
	182	goto err;
	183	name = OBJ_nid2sn(OBJ_obj2nid(kekalg->algorithm));
	184	kekcipher = EVP_CIPHER_fetch(pctx->libctx, name, pctx->propquery);
	185	if (kekcipher == NULL \|\| EVP_CIPHER_mode(kekcipher) != EVP_CIPH_WRAP_MODE)
	186	goto err;
	187	if (!EVP_EncryptInit_ex(kekctx, kekcipher, NULL, NULL, NULL))
	188	goto err;
	189	if (EVP_CIPHER_asn1_to_param(kekctx, kekalg->parameter) <= 0)
	190	goto err;
	191
	192	keylen = EVP_CIPHER_CTX_key_length(kekctx);
	193	if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
	194	goto err;
	195
	196	plen = CMS_SharedInfo_encode(&der, kekalg, ukm, keylen);
	197
	198	if (plen <= 0)
	199	goto err;
	200
	201	if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, der, plen) <= 0)
	202	goto err;
	203	der = NULL;
	204
	205	rv = 1;
	206	err:
	207	EVP_CIPHER_free(kekcipher);
	208	X509_ALGOR_free(kekalg);
	209	OPENSSL_free(der);
	210	return rv;
	211	}
	212
	213	static int ecdh_cms_decrypt(CMS_RecipientInfo *ri)
	214	{
	215	EVP_PKEY_CTX *pctx;
	216
	217	pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
	218	if (pctx == NULL)
	219	return 0;
	220	/* See if we need to set peer key */
	221	if (!EVP_PKEY_CTX_get0_peerkey(pctx)) {
	222	X509_ALGOR *alg;
	223	ASN1_BIT_STRING *pubkey;
	224
	225	if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &alg, &pubkey,
	226	NULL, NULL, NULL))
	227	return 0;
9ab7fe48	228	if (alg == NULL \|\| pubkey == NULL)
0b3a4ef2 MC	229	return 0;
0b3a4ef2 MC	230	if (!ecdh_cms_set_peerkey(pctx, alg, pubkey)) {
9311d0c4	231	ERR_raise(ERR_LIB_CMS, CMS_R_PEER_KEY_ERROR);
0b3a4ef2 MC	232	return 0;
	233	}
	234	}
	235	/* Set ECDH derivation parameters and initialise unwrap context */
	236	if (!ecdh_cms_set_shared_info(pctx, ri)) {
9311d0c4	237	ERR_raise(ERR_LIB_CMS, CMS_R_SHARED_INFO_ERROR);
0b3a4ef2 MC	238	return 0;
	239	}
	240	return 1;
	241	}
	242
	243	static int ecdh_cms_encrypt(CMS_RecipientInfo *ri)
	244	{
	245	EVP_PKEY_CTX *pctx;
	246	EVP_PKEY *pkey;
	247	EVP_CIPHER_CTX *ctx;
	248	int keylen;
	249	X509_ALGOR talg, wrap_alg = NULL;
	250	const ASN1_OBJECT *aoid;
	251	ASN1_BIT_STRING *pubkey;
	252	ASN1_STRING *wrap_str;
	253	ASN1_OCTET_STRING *ukm;
	254	unsigned char *penc = NULL;
	255	size_t penclen;
	256	int rv = 0;
	257	int ecdh_nid, kdf_type, kdf_nid, wrap_nid;
	258	const EVP_MD *kdf_md;
	259
	260	pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
	261	if (pctx == NULL)
	262	return 0;
	263	/* Get ephemeral key */
	264	pkey = EVP_PKEY_CTX_get0_pkey(pctx);
	265	if (!CMS_RecipientInfo_kari_get0_orig_id(ri, &talg, &pubkey,
	266	NULL, NULL, NULL))
	267	goto err;
	268	X509_ALGOR_get0(&aoid, NULL, NULL, talg);
	269	/* Is everything uninitialised? */
	270	if (aoid == OBJ_nid2obj(NID_undef)) {
	271	/* Set the key */
	272
5ac8fb58	273	penclen = EVP_PKEY_get1_encoded_public_key(pkey, &penc);
0b3a4ef2 MC	274	ASN1_STRING_set0(pubkey, penc, penclen);
	275	pubkey->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT \| 0x07);
	276	pubkey->flags \|= ASN1_STRING_FLAG_BITS_LEFT;
	277
	278	penc = NULL;
	279	X509_ALGOR_set0(talg, OBJ_nid2obj(NID_X9_62_id_ecPublicKey),
	280	V_ASN1_UNDEF, NULL);
	281	}
	282
	283	/* See if custom parameters set */
	284	kdf_type = EVP_PKEY_CTX_get_ecdh_kdf_type(pctx);
	285	if (kdf_type <= 0)
	286	goto err;
	287	if (!EVP_PKEY_CTX_get_ecdh_kdf_md(pctx, &kdf_md))
	288	goto err;
	289	ecdh_nid = EVP_PKEY_CTX_get_ecdh_cofactor_mode(pctx);
	290	if (ecdh_nid < 0)
	291	goto err;
	292	else if (ecdh_nid == 0)
	293	ecdh_nid = NID_dh_std_kdf;
	294	else if (ecdh_nid == 1)
	295	ecdh_nid = NID_dh_cofactor_kdf;
	296
	297	if (kdf_type == EVP_PKEY_ECDH_KDF_NONE) {
	298	kdf_type = EVP_PKEY_ECDH_KDF_X9_63;
	299	if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, kdf_type) <= 0)
	300	goto err;
	301	} else
	302	/* Unknown KDF */
	303	goto err;
	304	if (kdf_md == NULL) {
	305	/* Fixme later for better MD */
	306	kdf_md = EVP_sha1();
	307	if (EVP_PKEY_CTX_set_ecdh_kdf_md(pctx, kdf_md) <= 0)
	308	goto err;
	309	}
	310
	311	if (!CMS_RecipientInfo_kari_get0_alg(ri, &talg, &ukm))
	312	goto err;
	313
	314	/* Lookup NID for KDF+cofactor+digest */
	315
	316	if (!OBJ_find_sigid_by_algs(&kdf_nid, EVP_MD_type(kdf_md), ecdh_nid))
	317	goto err;
	318	/* Get wrap NID */
	319	ctx = CMS_RecipientInfo_kari_get0_ctx(ri);
	320	wrap_nid = EVP_CIPHER_CTX_type(ctx);
	321	keylen = EVP_CIPHER_CTX_key_length(ctx);
	322
	323	/* Package wrap algorithm in an AlgorithmIdentifier */
	324
	325	wrap_alg = X509_ALGOR_new();
	326	if (wrap_alg == NULL)
	327	goto err;
	328	wrap_alg->algorithm = OBJ_nid2obj(wrap_nid);
	329	wrap_alg->parameter = ASN1_TYPE_new();
	330	if (wrap_alg->parameter == NULL)
	331	goto err;
	332	if (EVP_CIPHER_param_to_asn1(ctx, wrap_alg->parameter) <= 0)
	333	goto err;
	334	if (ASN1_TYPE_get(wrap_alg->parameter) == NID_undef) {
	335	ASN1_TYPE_free(wrap_alg->parameter);
	336	wrap_alg->parameter = NULL;
	337	}
338
339	if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
340	goto err;
341
342	penclen = CMS_SharedInfo_encode(&penc, wrap_alg, ukm, keylen);
343
9ab7fe48	344	if (penclen == 0)
0b3a4ef2 MC	345	goto err;
	346
	347	if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, penc, penclen) <= 0)
	348	goto err;
	349	penc = NULL;
	350
	351	/*
	352	* Now need to wrap encoding of wrap AlgorithmIdentifier into parameter
	353	* of another AlgorithmIdentifier.
	354	*/
	355	penclen = i2d_X509_ALGOR(wrap_alg, &penc);
9ab7fe48	356	if (penc == NULL \|\| penclen == 0)
0b3a4ef2 MC	357	goto err;
	358	wrap_str = ASN1_STRING_new();
	359	if (wrap_str == NULL)
	360	goto err;
	361	ASN1_STRING_set0(wrap_str, penc, penclen);
	362	penc = NULL;
	363	X509_ALGOR_set0(talg, OBJ_nid2obj(kdf_nid), V_ASN1_SEQUENCE, wrap_str);
	364
	365	rv = 1;
	366
	367	err:
	368	OPENSSL_free(penc);
	369	X509_ALGOR_free(wrap_alg);
	370	return rv;
	371	}
	372
	373	int cms_ecdh_envelope(CMS_RecipientInfo *ri, int decrypt)
	374	{
9ab7fe48 MC	375	assert(decrypt == 0 \|\| decrypt == 1);
9ab7fe48 MC	376
0b3a4ef2 MC	377	if (decrypt == 1)
0b3a4ef2 MC	378	return ecdh_cms_decrypt(ri);
9ab7fe48 MC	379
9ab7fe48 MC	380	if (decrypt == 0)
0b3a4ef2 MC	381	return ecdh_cms_encrypt(ri);
0b3a4ef2 MC	382
9311d0c4	383	ERR_raise(ERR_LIB_CMS, CMS_R_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
0b3a4ef2	384	return 0;
9ab7fe48	385	}
9ab7fe48 MC	386
	387	/* ECDSA and DSA implementation is the same */
	388	int cms_ecdsa_dsa_sign(CMS_SignerInfo *si, int verify)
	389	{
	390	assert(verify == 0 \|\| verify == 1);
	391
	392	if (verify == 0) {
	393	int snid, hnid;
	394	X509_ALGOR alg1, alg2;
	395	EVP_PKEY *pkey = si->pkey;
	396
	397	CMS_SignerInfo_get0_algs(si, NULL, NULL, &alg1, &alg2);
	398	if (alg1 == NULL \|\| alg1->algorithm == NULL)
	399	return -1;
	400	hnid = OBJ_obj2nid(alg1->algorithm);
	401	if (hnid == NID_undef)
	402	return -1;
	403	if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
	404	return -1;
	405	X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
	406	}
	407	return 1;
	408	}