C
C
Verify and Unwrap S/MIME, and get Information about CMS Signature
See more MIME Examples
Demonstrates calling the Verify method to verify and unwrap S/MIME. The MIME is restored to the original structure that it would have originally had prior to signing. The Verify method works with both detached signatures, as well as opaque/attached signatures.Calls LastJsonData to get information about the signature(s) that were verified.
Chilkat C Downloads
#include <C_CkMime.h>
#include <C_CkJsonObject.h>
#include <C_CkDtObj.h>
void ChilkatSample(void)
{
BOOL success;
HCkMime mime;
BOOL verified;
HCkJsonObject json;
HCkDtObj signingTime;
HCkDtObj authAttrSigningTimeUtctime;
const char *issuerCN;
const char *serial;
const char *strVal;
const char *certSerialNumber;
const char *certIssuerCN;
const char *certDigestAlgOid;
const char *certDigestAlgName;
const char *contentType;
const char *messageDigest;
const char *signingAlgOid;
const char *signingAlgName;
const char *authAttrContentTypeName;
const char *authAttrContentTypeOid;
const char *authAttrSigningTimeName;
const char *authAttrMessageDigestName;
const char *authAttrMessageDigestDigest;
const char *authAttr1_2_840_113549_1_9_15Der;
const char *authAttr1_3_6_1_4_1_311_16_4Der;
int i;
int count_i;
success = FALSE;
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
mime = CkMime_Create();
// Load the signed MIME from a file...
success = CkMime_LoadMimeFile(mime,"qa_data/mime/detached_sig.eml");
if (success == FALSE) {
printf("%s\n",CkMime_lastErrorText(mime));
CkMime_Dispose(mime);
return;
}
// Verify the S/MIME and restore the MIME
// to the structure/content it had prior to signing.
verified = CkMime_Verify(mime);
if (verified == FALSE) {
printf("%s\n",CkMime_lastErrorText(mime));
CkMime_Dispose(mime);
return;
}
// Examine the details of what was verified.
json = CkJsonObject_Create();
CkMime_GetLastJsonData(mime,json);
CkJsonObject_putEmitCompact(json,FALSE);
printf("%s\n",CkJsonObject_emit(json));
// The code to parse the following JSON (i.e. extract desired information) is shown below..
// {
// "pkcs7": {
// "verify": {
// "certs": [
// {
// "issuerCN": "VeriSign Class 1 Public Primary Certification Authority - G3",
// "serial": "0702A21A85B84B659E180A6EE6F5A365"
// },
// {
// "issuerCN": "VeriSign Class 1 Public Primary Certification Authority - G3",
// "serial": "008B5B75568454850B00CFAF3848CEB1A4"
// },
// {
// "issuerCN": "Symantec Class 1 Individual Subscriber CA - G5",
// "serial": "619C55C32FF6BD1A7B7E0330D21C8F3C"
// }
// ],
// "digestAlgorithms": [
// "sha1"
// ],
// "signerInfo": [
// {
// "cert": {
// "serialNumber": "619C55C32FF6BD1A7B7E0330D21C8F3C",
// "issuerCN": "Symantec Class 1 Individual Subscriber CA - G5",
// "digestAlgOid": "1.3.14.3.2.26",
// "digestAlgName": "SHA1"
// },
// "contentType": "1.2.840.113549.1.7.1",
// "signingTime": "160428055000Z",
// "messageDigest": "2hJJVmO/jtaJV5uCKMFzIkRRvtY=",
// "signingAlgOid": "1.2.840.113549.1.1.1",
// "signingAlgName": "RSA-PKCSV-1_5",
// "authAttr": {
// "1.2.840.113549.1.9.3": {
// "name": "contentType",
// "oid": "1.2.840.113549.1.7.1"
// },
// "1.2.840.113549.1.9.5": {
// "name": "signingTime",
// "utctime": "160428055000Z"
// },
// "1.2.840.113549.1.9.4": {
// "name": "messageDigest",
// "digest": "2hJJVmO/jtaJV5uCKMFzIkRRvtY="
// },
// "1.2.840.113549.1.9.15": {
// "der": "MFAwCwYJYIZIAWUDBAECMAoGCCqGSIb3DQMHMA4GCCqGSIb3DQMCAgIAgDANBggqhkiG9w0DAgIBQDAHBgUrDgMCBzANBggqhkiG9w0DAgIBKA=="
// },
// "1.3.6.1.4.1.311.16.4": {
// "der": "MIG7MIG...7fgMw0hyPPA=="
// }
// }
// }
// ]
// }
// }
// }
// Use this online tool to generate parsing code from sample JSON:
// Generate Parsing Code from JSON
signingTime = CkDtObj_Create();
authAttrSigningTimeUtctime = CkDtObj_Create();
i = 0;
count_i = CkJsonObject_SizeOfArray(json,"pkcs7.verify.certs");
while (i < count_i) {
CkJsonObject_putI(json,i);
issuerCN = CkJsonObject_stringOf(json,"pkcs7.verify.certs[i].issuerCN");
serial = CkJsonObject_stringOf(json,"pkcs7.verify.certs[i].serial");
i = i + 1;
}
i = 0;
count_i = CkJsonObject_SizeOfArray(json,"pkcs7.verify.digestAlgorithms");
while (i < count_i) {
CkJsonObject_putI(json,i);
strVal = CkJsonObject_stringOf(json,"pkcs7.verify.digestAlgorithms[i]");
i = i + 1;
}
i = 0;
count_i = CkJsonObject_SizeOfArray(json,"pkcs7.verify.signerInfo");
while (i < count_i) {
CkJsonObject_putI(json,i);
certSerialNumber = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].cert.serialNumber");
certIssuerCN = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].cert.issuerCN");
certDigestAlgOid = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].cert.digestAlgOid");
certDigestAlgName = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].cert.digestAlgName");
contentType = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].contentType");
CkJsonObject_DtOf(json,"pkcs7.verify.signerInfo[i].signingTime",FALSE,signingTime);
messageDigest = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].messageDigest");
signingAlgOid = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].signingAlgOid");
signingAlgName = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].signingAlgName");
authAttrContentTypeName = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".name");
authAttrContentTypeOid = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".oid");
authAttrSigningTimeName = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".name");
CkJsonObject_DtOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".utctime",FALSE,authAttrSigningTimeUtctime);
authAttrMessageDigestName = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".name");
authAttrMessageDigestDigest = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".digest");
authAttr1_2_840_113549_1_9_15Der = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.15\".der");
authAttr1_3_6_1_4_1_311_16_4Der = CkJsonObject_stringOf(json,"pkcs7.verify.signerInfo[i].authAttr.\"1.3.6.1.4.1.311.16.4\".der");
i = i + 1;
}
CkMime_Dispose(mime);
CkJsonObject_Dispose(json);
CkDtObj_Dispose(signingTime);
CkDtObj_Dispose(authAttrSigningTimeUtctime);
}