Add CMS ECC support.

This brings in EC code from OpenSSL 1.1.1b, with style(9) and whitespace
cleanups. All of this code is currently under OPENSSL_NO_CMS hence is a
no-op.

ok inoguchi@

1 files changed, 370 insertions, 2 deletions

diff --git a/src/lib/libcrypto/ec/ec_ameth.c b/src/lib/libcrypto/ec/ec_ameth.c
index 04c068200f..a7e80c73d7 100644
--- a/src/lib/libcrypto/ec/ec_ameth.c
+++ b/src/lib/libcrypto/ec/ec_ameth.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ec_ameth.c,v 1.25 2018/08/24 20:22:15 tb Exp $ */
+/* $OpenBSD: ec_ameth.c,v 1.26 2019/09/08 17:00:05 jsing Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2006.
  */
@@ -65,9 +65,15 @@
 #include <openssl/err.h>
 #include <openssl/x509.h>
 
-
 #include "asn1_locl.h"
 
+#ifndef OPENSSL_NO_CMS
+#include <openssl/cms.h>
+
+static int ecdh_cms_decrypt(CMS_RecipientInfo *ri);
+static int ecdh_cms_encrypt(CMS_RecipientInfo *ri);
+#endif
+
 static int 
 eckey_param2type(int *pptype, void **ppval, EC_KEY * ec_key)
 {
@@ -573,6 +579,36 @@ ec_pkey_ctrl(EVP_PKEY * pkey, int op, long arg1, void *arg2)
                 }
                 return 1;
 
+#ifndef OPENSSL_NO_CMS
+        case ASN1_PKEY_CTRL_CMS_SIGN:
+                if (arg1 == 0) {
+                        X509_ALGOR *alg1, *alg2;
+                        int snid, hnid;
+
+                        CMS_SignerInfo_get0_algs(arg2, 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;
+
+        case ASN1_PKEY_CTRL_CMS_ENVELOPE:
+                if (arg1 == 0)
+                        return ecdh_cms_encrypt(arg2);
+                else if (arg1 == 1)
+                        return ecdh_cms_decrypt(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:
                 *(int *) arg2 = NID_sha1;
                 return 2;
@@ -584,6 +620,338 @@ ec_pkey_ctrl(EVP_PKEY * pkey, int op, long arg1, void *arg2)
 
 }
 
+#ifndef OPENSSL_NO_CMS
+
+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;
+        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 == NULL)
+                        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_get0_data(pubkey);
+        if (!p || !plen)
+                goto err;
+        if (!o2i_ECPublicKey(&ecpeer, &p, plen))
+                goto err;
+        pkpeer = EVP_PKEY_new();
+        if (pkpeer == NULL)
+                goto err;
+        EVP_PKEY_set1_EC_KEY(pkpeer, ecpeer);
+        if (EVP_PKEY_derive_set_peer(pctx, pkpeer) > 0)
+                rv = 1;
+ err:
+        EC_KEY_free(ecpeer);
+        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)
+{
+        X509_ALGOR *alg, *kekalg = NULL;
+        ASN1_OCTET_STRING *ukm;
+        const unsigned char *p;
+        unsigned char *der = NULL;
+        int plen, keylen;
+        const EVP_CIPHER *kekcipher;
+        EVP_CIPHER_CTX *kekctx;
+        int rv = 0;
+
+        if (!CMS_RecipientInfo_kari_get0_alg(ri, &alg, &ukm))
+                return 0;
+
+        if (!ecdh_cms_set_kdf_param(pctx, OBJ_obj2nid(alg->algorithm))) {
+                ECerror(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;
+
+        plen = CMS_SharedInfo_encode(&der, kekalg, ukm, keylen);
+        if (!plen)
+                goto err;
+
+        if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, der, plen) <= 0)
+                goto err;
+        der = NULL;
+
+        rv = 1;
+ err:
+        X509_ALGOR_free(kekalg);
+        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)
+                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)) {
+                        ECerror(EC_R_PEER_KEY_ERROR);
+                        return 0;
+                }
+        }
+
+        /* Set ECDH derivation parameters and initialise unwrap context */
+        if (!ecdh_cms_set_shared_info(pctx, ri)) {
+                ECerror(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;
+        const ASN1_OBJECT *aoid;
+        ASN1_BIT_STRING *pubkey;
+        ASN1_STRING *wrap_str;
+        ASN1_OCTET_STRING *ukm;
+        unsigned char *penc = NULL;
+        int penclen;
+        int ecdh_nid, kdf_type, kdf_nid, wrap_nid;
+        const EVP_MD *kdf_md;
+        int rv = 0;
+
+        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;
+                unsigned char *p;
+
+                /* Set the key */
+                penclen = i2o_ECPublicKey(eckey, NULL);
+                if (penclen <= 0)
+                        goto err;
+                penc = malloc(penclen);
+                if (penc == NULL)
+                        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 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)
+                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 || !penclen)
+                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:
+        free(penc);
+        X509_ALGOR_free(wrap_alg);
+        return rv;
+}
+
+#endif
+
 const EVP_PKEY_ASN1_METHOD eckey_asn1_meth = {
         .pkey_id = EVP_PKEY_EC,
         .pkey_base_id = EVP_PKEY_EC,