#ifndef OPENSSL_NO_CMS
#include <openssl/cms.h>
#endif
+#include <openssl/asn1t.h>
#include "asn1_locl.h"
+static int ecdh_cms_decrypt(CMS_RecipientInfo *ri);
+static int ecdh_cms_encrypt(CMS_RecipientInfo *ri);
+
static int eckey_param2type(int *pptype, void **ppval, EC_KEY *ec_key)
{
const EC_GROUP *group;
if (!pstr)
return 0;
pstr->length = i2d_ECParameters(ec_key, &pstr->data);
- if (pstr->length < 0)
+ if (pstr->length <= 0)
{
ASN1_STRING_free(pstr);
ECerr(EC_F_ECKEY_PARAM2TYPE, ERR_R_EC_LIB);
X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
}
return 1;
+
+ case ASN1_PKEY_CTRL_CMS_ENVELOPE:
+ if (arg1 == 1)
+ return ecdh_cms_decrypt(arg2);
+ else if (arg1 == 0)
+ return ecdh_cms_encrypt(arg2);
+ return -2;
+
+ case ASN1_PKEY_CTRL_CMS_RI_TYPE:
+ *(int *)arg2 = CMS_RECIPINFO_AGREE;
+ return 1;
#endif
case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
ec_copy_parameters,
ec_cmp_parameters,
eckey_param_print,
+ 0,
int_ec_free,
ec_pkey_ctrl,
old_ec_priv_decode,
old_ec_priv_encode
};
+
+#ifndef OPENSSL_NO_CMS
+
+static int ecdh_cms_set_peerkey(EVP_PKEY_CTX *pctx,
+ X509_ALGOR *alg, ASN1_BIT_STRING *pubkey)
+ {
+ ASN1_OBJECT *aoid;
+ int atype;
+ void *aval;
+ int rv = 0;
+ EVP_PKEY *pkpeer = NULL;
+ EC_KEY *ecpeer = 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)
+ {
+ const EC_GROUP *grp;
+ EVP_PKEY *pk;
+ pk = EVP_PKEY_CTX_get0_pkey(pctx);
+ if (!pk)
+ goto err;
+ grp = EC_KEY_get0_group(pk->pkey.ec);
+ ecpeer = EC_KEY_new();
+ if (!ecpeer)
+ goto err;
+ if (!EC_KEY_set_group(ecpeer, grp))
+ goto err;
+ }
+ else
+ {
+ ecpeer = eckey_type2param(atype, aval);
+ if (!ecpeer)
+ goto err;
+ }
+ /* We have parameters now set public key */
+ plen = ASN1_STRING_length(pubkey);
+ p = ASN1_STRING_data(pubkey);
+ if (!p || !plen)
+ goto err;
+ if (!o2i_ECPublicKey(&ecpeer, &p, plen))
+ goto err;
+ pkpeer = EVP_PKEY_new();
+ if (!pkpeer)
+ goto err;
+ EVP_PKEY_set1_EC_KEY(pkpeer, ecpeer);
+ if (EVP_PKEY_derive_set_peer(pctx, pkpeer) > 0)
+ rv = 1;
+ err:
+ if (ecpeer)
+ EC_KEY_free(ecpeer);
+ if (pkpeer)
+ 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_62) <= 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;
+ }
+
+/* Utilities to encode the ECC_CMS_SharedInfo structure used during key
+ * derivation.
+ */
+
+typedef struct {
+ X509_ALGOR *keyInfo;
+ ASN1_OCTET_STRING *entityUInfo;
+ ASN1_OCTET_STRING *suppPubInfo;
+} ECC_CMS_SharedInfo;
+
+ASN1_SEQUENCE(ECC_CMS_SharedInfo) = {
+ ASN1_SIMPLE(ECC_CMS_SharedInfo, keyInfo, X509_ALGOR),
+ ASN1_EXP_OPT(ECC_CMS_SharedInfo, entityUInfo, ASN1_OCTET_STRING, 0),
+ ASN1_EXP_OPT(ECC_CMS_SharedInfo, suppPubInfo, ASN1_OCTET_STRING, 2),
+} ASN1_SEQUENCE_END(ECC_CMS_SharedInfo)
+
+static int ecdh_cms_set_ukm(EVP_PKEY_CTX *pctx,
+ X509_ALGOR *kekalg,
+ ASN1_OCTET_STRING *ukm,
+ int keylen)
+ {
+ union {
+ ECC_CMS_SharedInfo *pecsi;
+ ASN1_VALUE *a;
+ } intsi = {NULL};
+
+ unsigned char *der = NULL;
+ int plen;
+ ASN1_OCTET_STRING oklen;
+ unsigned char kl[4];
+ ECC_CMS_SharedInfo ecsi;
+
+ keylen <<= 3;
+ kl[0] = (keylen >> 24) & 0xff;
+ kl[1] = (keylen >> 16) & 0xff;
+ kl[2] = (keylen >> 8) & 0xff;
+ kl[3] = keylen & 0xff;
+ oklen.length = 4;
+ oklen.data = kl;
+ oklen.type = V_ASN1_OCTET_STRING;
+ oklen.flags = 0;
+ ecsi.keyInfo = kekalg;
+ ecsi.entityUInfo = ukm;
+ ecsi.suppPubInfo = &oklen;
+ intsi.pecsi = &ecsi;
+ plen = ASN1_item_i2d(intsi.a, &der, ASN1_ITEM_rptr(ECC_CMS_SharedInfo));
+ if (!der || !plen)
+ goto err;
+ if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, der, plen) <= 0)
+ goto err;
+ return 1;
+ err:
+ if (der)
+ OPENSSL_free(der);
+ return 0;
+ }
+
+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;
+ int plen, keylen;
+ const EVP_CIPHER *kekcipher;
+ EVP_CIPHER_CTX *kekctx;
+
+ if (!CMS_RecipientInfo_kari_get0_alg(ri, &alg, &ukm))
+ return 0;
+
+ if (!ecdh_cms_set_kdf_param(pctx, OBJ_obj2nid(alg->algorithm)))
+ {
+ ECerr(EC_F_ECDH_CMS_SET_SHARED_INFO, EC_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)
+ goto err;
+ kekctx = CMS_RecipientInfo_kari_get0_ctx(ri);
+ if (!kekctx)
+ goto err;
+ kekcipher = EVP_get_cipherbyobj(kekalg->algorithm);
+ if (!kekcipher || 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;
+
+ if (!ecdh_cms_set_ukm(pctx, kekalg, ukm, keylen))
+ goto err;
+
+ rv = 1;
+ err:
+ if (kekalg)
+ X509_ALGOR_free(kekalg);
+ return rv;
+ }
+
+static int ecdh_cms_decrypt(CMS_RecipientInfo *ri)
+ {
+ EVP_PKEY_CTX *pctx;
+ pctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
+ if (!pctx)
+ 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 || !pubkey)
+ return 0;
+ if (!ecdh_cms_set_peerkey(pctx, alg, pubkey))
+ {
+ ECerr(EC_F_ECDH_CMS_DECRYPT, EC_R_PEER_KEY_ERROR);
+ return 0;
+ }
+ }
+ /* Set ECDH derivation parameters and initialise unwrap context */
+ if (!ecdh_cms_set_shared_info(pctx, ri))
+ {
+ ECerr(EC_F_ECDH_CMS_DECRYPT, EC_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;
+ ASN1_OBJECT *aoid;
+ ASN1_BIT_STRING *pubkey;
+ ASN1_STRING *wrap_str;
+ ASN1_OCTET_STRING *ukm;
+ unsigned char *penc = NULL;
+ int 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)
+ 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))
+ {
+
+ EC_KEY *eckey = pkey->pkey.ec;
+ /* Set the key */
+ unsigned char *p;
+
+ penclen = i2o_ECPublicKey(eckey, NULL);
+ if (penclen <= 0)
+ goto err;
+ penc = OPENSSL_malloc(penclen);
+ if (!penc)
+ goto err;
+ p = penc;
+ penclen = i2o_ECPublicKey(eckey, &p);
+ if (penclen <= 0)
+ goto err;
+ 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 paraneters 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_62;
+ if (EVP_PKEY_CTX_set_ecdh_kdf_type(pctx, kdf_type) <= 0)
+ goto err;
+ }
+ else
+ /* Uknown 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)
+ goto err;
+ wrap_alg->algorithm = OBJ_nid2obj(wrap_nid);
+ wrap_alg->parameter = ASN1_TYPE_new();
+ if (!wrap_alg->parameter)
+ 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;
+ if (!ecdh_cms_set_ukm(pctx, wrap_alg, ukm, keylen))
+ goto err;
+
+ /* Now need to wrap encoding of wrap AlgorithmIdentifier into
+ * parameter of another AlgorithmIdentifier.
+ */
+ penc = NULL;
+ penclen = i2d_X509_ALGOR(wrap_alg, &penc);
+ if (!penc || !penclen)
+ goto err;
+ wrap_str = ASN1_STRING_new();
+ if (!wrap_str)
+ 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:
+ if (penc)
+ OPENSSL_free(penc);
+ if (wrap_alg)
+ X509_ALGOR_free(wrap_alg);
+ return rv;
+ }
+
+#endif
projects / openssl.git / blobdiff