1 /*******************************************************************************
2 * Copyright 2013-2018 Intel Corporation
3 * All Rights Reserved.
4 *
5 * If this  software was obtained  under the  Intel Simplified  Software License,
6 * the following terms apply:
7 *
8 * The source code,  information  and material  ("Material") contained  herein is
9 * owned by Intel Corporation or its  suppliers or licensors,  and  title to such
10 * Material remains with Intel  Corporation or its  suppliers or  licensors.  The
11 * Material  contains  proprietary  information  of  Intel or  its suppliers  and
12 * licensors.  The Material is protected by  worldwide copyright  laws and treaty
13 * provisions.  No part  of  the  Material   may  be  used,  copied,  reproduced,
14 * modified, published,  uploaded, posted, transmitted,  distributed or disclosed
15 * in any way without Intel's prior express written permission.  No license under
16 * any patent,  copyright or other  intellectual property rights  in the Material
17 * is granted to  or  conferred  upon  you,  either   expressly,  by implication,
18 * inducement,  estoppel  or  otherwise.  Any  license   under such  intellectual
19 * property rights must be express and approved by Intel in writing.
20 *
21 * Unless otherwise agreed by Intel in writing,  you may not remove or alter this
22 * notice or  any  other  notice   embedded  in  Materials  by  Intel  or Intel's
23 * suppliers or licensors in any way.
24 *
25 *
26 * If this  software  was obtained  under the  Apache License,  Version  2.0 (the
27 * "License"), the following terms apply:
28 *
29 * You may  not use this  file except  in compliance  with  the License.  You may
30 * obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
31 *
32 *
33 * Unless  required  by   applicable  law  or  agreed  to  in  writing,  software
34 * distributed under the License  is distributed  on an  "AS IS"  BASIS,  WITHOUT
35 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
36 *
37 * See the   License  for the   specific  language   governing   permissions  and
38 * limitations under the License.
39 *******************************************************************************/
40 
41 /*
42 //
43 //  Purpose:
44 //     Cryptography Primitive.
45 //     EC over Prime Finite Field (Verify Signature, SM2 version)
46 //
47 //  Contents:
48 //     ippsECCPVerifySM2()
49 //
50 //
51 */
52 
53 #include "owndefs.h"
54 #include "owncp.h"
55 #include "pcpeccp.h"
56 
57 
58 /*F*
59 //    Name: ippsECCPVerifySM2
60 //
61 // Purpose: Verify Signature (SM2 version).
62 //
63 // Returns:                   Reason:
64 //    ippStsNullPtrErr           NULL == pEC
65 //                               NULL == pMsgDigest
66 //                               NULL == pRegPublic
67 //                               NULL == pSignR
68 //                               NULL == pSignS
69 //                               NULL == pResult
70 //
71 //    ippStsContextMatchErr      illegal pEC->idCtx
72 //                               illegal pMsgDigest->idCtx
73 //                               illegal pRegPublic->idCtx
74 //                               illegal pSignR->idCtx
75 //                               illegal pSignS->idCtx
76 //
77 //    ippStsMessageErr           0> MsgDigest
78 //                               order<= MsgDigest
79 //
80 //    ippStsRangeErr             SignR < 0 or SignS < 0
81 //
82 //    ippStsNoErr                no errors
83 //
84 // Parameters:
85 //    pMsgDigest     pointer to the message representative to being signed
86 //    pRegPublic     pointer to the regular public key
87 //    pSignR,pSignS  pointer to the signature
88 //    pResult        pointer to the result: ippECValid/ippECInvalidSignature
89 //    pEC            pointer to the ECCP context
90 //
91 *F*/
92 IPPFUN(IppStatus, ippsECCPVerifySM2,(const IppsBigNumState* pMsgDigest,
93                                      const IppsECCPPointState* pRegPublic,
94                                      const IppsBigNumState* pSignR, const IppsBigNumState* pSignS,
95                                      IppECResult* pResult,
96                                      IppsECCPState* pEC))
97 {
98    IppsGFpState* pGF;
99    gsModEngine* pGFE;
100 
101    /* use aligned EC context */
102    IPP_BAD_PTR1_RET(pEC);
103    pEC = (IppsGFpECState*)( IPP_ALIGNED_PTR(pEC, ECGFP_ALIGNMENT) );
104    IPP_BADARG_RET(!ECP_TEST_ID(pEC), ippStsContextMatchErr);
105 
106    pGF = ECP_GFP(pEC);
107    pGFE = GFP_PMA(pGF);
108 
109    /* test message representative */
110    IPP_BAD_PTR1_RET(pMsgDigest);
111    pMsgDigest = (IppsBigNumState*)( IPP_ALIGNED_PTR(pMsgDigest, ALIGN_VAL) );
112    IPP_BADARG_RET(!BN_VALID_ID(pMsgDigest), ippStsContextMatchErr);
113    IPP_BADARG_RET(BN_NEGATIVE(pMsgDigest), ippStsMessageErr);
114 
115    /* test regular public key */
116    IPP_BAD_PTR1_RET(pRegPublic);
117    IPP_BADARG_RET( !ECP_POINT_TEST_ID(pRegPublic), ippStsContextMatchErr );
118    IPP_BADARG_RET( ECP_POINT_FELEN(pRegPublic)!=GFP_FELEN(pGFE), ippStsOutOfRangeErr);
119 
120    /* test result */
121    IPP_BAD_PTR1_RET(pResult);
122 
123    /* test signature */
124    IPP_BAD_PTR2_RET(pSignR, pSignS);
125    pSignR = (IppsBigNumState*)( IPP_ALIGNED_PTR(pSignR, ALIGN_VAL) );
126    pSignS = (IppsBigNumState*)( IPP_ALIGNED_PTR(pSignS, ALIGN_VAL) );
127    IPP_BADARG_RET(!BN_VALID_ID(pSignR), ippStsContextMatchErr);
128    IPP_BADARG_RET(!BN_VALID_ID(pSignS), ippStsContextMatchErr);
129    IPP_BADARG_RET(BN_NEGATIVE(pSignR), ippStsRangeErr);
130    IPP_BADARG_RET(BN_NEGATIVE(pSignS), ippStsRangeErr);
131 
132    {
133       IppECResult vResult = ippECInvalidSignature;
134 
135       gsModEngine* pMontR = ECP_MONT_R(pEC);
136       BNU_CHUNK_T* pOrder = MOD_MODULUS(pMontR);
137       int orderLen = MOD_LEN(pMontR);
138 
139       BNU_CHUNK_T* pMsgData = BN_NUMBER(pMsgDigest);
140       int msgLen = BN_SIZE(pMsgDigest);
141 
142       /* test message value */
143       IPP_BADARG_RET(0<=cpCmp_BNU(pMsgData, msgLen, pOrder, orderLen), ippStsMessageErr);
144 
145       /* test signature value */
146       if(!cpEqu_BNU_CHUNK(BN_NUMBER(pSignR), BN_SIZE(pSignR), 0) &&
147          !cpEqu_BNU_CHUNK(BN_NUMBER(pSignS), BN_SIZE(pSignS), 0) &&
148          0>cpCmp_BNU(BN_NUMBER(pSignR), BN_SIZE(pSignR), pOrder, orderLen) &&
149          0>cpCmp_BNU(BN_NUMBER(pSignS), BN_SIZE(pSignS), pOrder, orderLen)) {
150 
151          int elmLen = GFP_FELEN(pGFE);
152          int ns;
153 
154          BNU_CHUNK_T* r = cpGFpGetPool(4, pGFE);
155          BNU_CHUNK_T* s = r+orderLen;
156          BNU_CHUNK_T* t = s+orderLen;
157          BNU_CHUNK_T* f = t+orderLen;
158 
159          /* expand signatire's components */
160          cpGFpElementCopyPadd(r, orderLen, BN_NUMBER(pSignR), BN_SIZE(pSignR));
161          cpGFpElementCopyPadd(s, orderLen, BN_NUMBER(pSignS), BN_SIZE(pSignS));
162 
163          /* t = (r+s) mod order */
164          cpModAdd_BNU(t, r, s, pOrder, orderLen, f);
165 
166          /* P = [s]G +[t]regPublic, t = P.x */
167          {
168             IppsGFpECPoint P, G;
169             cpEcGFpInitPoint(&P, cpEcGFpGetPool(1, pEC),0, pEC);
170             cpEcGFpInitPoint(&G, ECP_G(pEC), ECP_AFFINE_POINT|ECP_FINITE_POINT, pEC);
171 
172             gfec_BasePointProduct(&P,
173                                   s, orderLen, pRegPublic, t, orderLen,
174                                   pEC, (Ipp8u*)ECP_SBUFFER(pEC));
175 
176             gfec_GetPoint(t, NULL, &P, pEC);
177             GFP_METHOD(pGFE)->decode(t, t, pGFE);
178             ns = cpMod_BNU(t, elmLen, pOrder, orderLen);
179 
180             cpEcGFpReleasePool(1, pEC);
181          }
182 
183          /* t = (msg+t) mod order */
184          cpGFpElementCopyPadd(f, orderLen, pMsgData, msgLen);
185          cpModAdd_BNU(t, t, f, pOrder, orderLen, f);
186 
187          if(GFP_EQ(t, r, orderLen))
188             vResult = ippECValid;
189 
190          cpGFpReleasePool(4, pGFE);
191       }
192 
193       *pResult = vResult;
194       return ippStsNoErr;
195    }
196 }
197