(Unicode C++) Verify a .p7m and get Algorithm Information

Demonstrates how to verify a .p7m and then examine the algorithms used by the signature.

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#include <CkCrypt2W.h>
#include <CkJsonObjectW.h>

void ChilkatSample(void)
    {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkCrypt2W crypt;

    const wchar_t *inFile = L"qa_data/p7m/brainpoolP256r1.p7m";
    const wchar_t *outFile = L"qa_output/something.dat";

    // Verify and extract the signed data.
    bool success = crypt.VerifyP7M(inFile,outFile);
    if (success == false) {
        wprintf(L"%s\n",crypt.lastErrorText());
        return;
    }

    // Examine details about the signature(s)
    CkJsonObjectW *json = crypt.LastJsonData();
    json->put_EmitCompact(false);
    wprintf(L"%s\n",json->emit());

    // Sample output

    // {
    //   "pkcs7": {
    //     "verify": {
    //       "digestAlgorithms": [
    //         "sha256"
    //       ],
    //       "signerInfo": [
    //         {
    //           "cert": {
    //             "serialNumber": "FFFFE552B302FFFFFF1E34C3ACEB2FFFF",
    //             "issuerCN": "The common name of the cert...",
    //             "issuerDN": "",
    //             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
    //             "digestAlgName": "SHA256"
    //           },
    //           "contentType": "1.2.840.113549.1.7.1",
    //           "signingTime": "190409140500Z",
    //           "messageDigest": "lQe9If7vZKFf/NlSYu5Esmlw3phVK/RFsbbb1uH73t8=",
    //           "signingAlgOid": "1.2.840.10045.4.3.2",
    //           "signerDigest": "lQe9If7vZKFf/NlSYu5Esmlw3phVK/RFsbbb1uH73t8=",
    //           "authAttr": [
    //             {
    //               "oid": "1.2.840.113549.1.9.3",
    //               "oidName": "contentType"
    //             },
    //             {
    //               "oid": "1.2.840.113549.1.9.5",
    //               "oidName": "signingTime"
    //             },
    //             {
    //               "oid": "1.2.840.113549.1.9.52",
    //               "oidName": "1.2.840.113549.1.9.52",
    //               "der": "MBs ... AwI="
    //             },
    //             {
    //               "oid": "1.2.840.113549.1.9.4",
    //               "oidName": "messageDigest"
    //             },
    //             {
    //               "oid": "1.2.840.113549.1.9.16.2.47",
    //               "oidName": "signingCertificateV2",
    //               "der": "MCYw .. 7PlQ=="
    //             },
    //             {
    //               "oid": "1.2.840.113549.1.9.20",
    //               "oidName": "1.2.840.113549.1.9.20"
    //             }
    //           ]
    //         }
    //       ]
    //     }
    //   }
    // }

    // Code for parsing the above JSON...
    int i;
    int count_i;
    const wchar_t *strVal = 0;
    const wchar_t *certSerialNumber = 0;
    const wchar_t *certIssuerCN = 0;
    const wchar_t *certIssuerDN = 0;
    const wchar_t *certDigestAlgOid = 0;
    const wchar_t *certDigestAlgName = 0;
    const wchar_t *contentType = 0;
    const wchar_t *signingTime = 0;
    const wchar_t *messageDigest = 0;
    const wchar_t *signingAlgOid = 0;
    const wchar_t *signerDigest = 0;
    int j;
    int count_j;
    const wchar_t *oid = 0;
    const wchar_t *oidName = 0;
    const wchar_t *der = 0;

    i = 0;
    count_i = json->SizeOfArray(L"pkcs7.verify.digestAlgorithms");
    while (i < count_i) {
        json->put_I(i);
        strVal = json->stringOf(L"pkcs7.verify.digestAlgorithms[i]");
        i = i + 1;
    }

    i = 0;
    count_i = json->SizeOfArray(L"pkcs7.verify.signerInfo");
    while (i < count_i) {
        json->put_I(i);
        certSerialNumber = json->stringOf(L"pkcs7.verify.signerInfo[i].cert.serialNumber");
        certIssuerCN = json->stringOf(L"pkcs7.verify.signerInfo[i].cert.issuerCN");
        certIssuerDN = json->stringOf(L"pkcs7.verify.signerInfo[i].cert.issuerDN");
        certDigestAlgOid = json->stringOf(L"pkcs7.verify.signerInfo[i].cert.digestAlgOid");
        certDigestAlgName = json->stringOf(L"pkcs7.verify.signerInfo[i].cert.digestAlgName");
        contentType = json->stringOf(L"pkcs7.verify.signerInfo[i].contentType");
        signingTime = json->stringOf(L"pkcs7.verify.signerInfo[i].signingTime");
        messageDigest = json->stringOf(L"pkcs7.verify.signerInfo[i].messageDigest");
        signingAlgOid = json->stringOf(L"pkcs7.verify.signerInfo[i].signingAlgOid");
        signerDigest = json->stringOf(L"pkcs7.verify.signerInfo[i].signerDigest");
        j = 0;
        count_j = json->SizeOfArray(L"pkcs7.verify.signerInfo[i].authAttr");
        while (j < count_j) {
            json->put_J(j);
            oid = json->stringOf(L"pkcs7.verify.signerInfo[i].authAttr[j].oid");
            oidName = json->stringOf(L"pkcs7.verify.signerInfo[i].authAttr[j].oidName");
            der = json->stringOf(L"pkcs7.verify.signerInfo[i].authAttr[j].der");
            j = j + 1;
        }

        i = i + 1;
    }

    delete json;

    wprintf(L"Success!\n");
    }