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Objective-C

Duplicate CSR Created by OpenSSL with Config.cnf

See more CSR Examples

Demonstrates how to duplicate a CSR created by the following commands:
# Generate Private Key
openssl ecparam -name secp256k1 -genkey -noout -out PrivateKey.pem

#Generate CSR
openssl req -new -sha256 -key PrivateKey.pem -extensions v3_req -config Config.cnf -out CSR.csr

Chilkat Objective-C Downloads

Objective-C
#import <CkoStringBuilder.h>
#import <CkoCsr.h>
#import <CkoXml.h>
#import <CkoEcc.h>
#import <CkoPrng.h>
#import <CkoPrivateKey.h>
#import <NSString.h>

BOOL success = NO;

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// This example duplicates the CSR created by OpenSSL with the following config file:

// oid_section = OIDs
// [ OIDs ]
// certificateTemplateName= 1.3.6.1.4.1.311.20.2
// 
// [ req ]
// default_bits 	= 2048
// emailAddress 	= it@example.sa
// req_extensions	= v3_req
// x509_extensions 	= v3_ca
// prompt = no
// default_md = sha256
// req_extensions = req_ext
// distinguished_name = dn
// 
// [ v3_req ]
// basicConstraints = CA:FALSE
// keyUsage = digitalSignature, nonRepudiation, keyEncipherment
// 
// [req_ext]
// certificateTemplateName = ASN1:PRINTABLESTRING:ZATCA-Code-Signing
// subjectAltName = dirName:alt_names
// 
// [ dn ]
// CN =EXAMPLE-CORP  				# Common Name
// C=SA									# Country Code e.g SA
// OU=HEAD-OFFICE							# Organization Unit Name
// O=ASC									# Organization Name
// 
// [alt_names]
// SN=1-ASC|2-V01|3-1234567890				# EGS Serial Number 1-ABC|2-PQR|3-XYZ
// UID=312345678900003						# Organization Identifier (VAT Number)
// title=1100								# Invoice Type
// registeredAddress=Dammam  	 			# Address
// businessCategory=IT						# Business Category

// The OpenSSL commands we are duplicating:

// openssl ecparam -name secp256k1 -genkey -noout -out PrivateKey.pem
// openssl req -new -sha256 -key PrivateKey.pem -extensions v3_req -config Config.cnf -out CSR.csr

// The 1st step is to actually use OpenSSL to generate a sample CSR.csr that we wish to duplicate.
// With the sample CSR.csr, we get the ExtensionRequest as XML.  
// For example:

CkoStringBuilder *sbCsr = [[CkoStringBuilder alloc] init];
success = [sbCsr LoadFile: @"qa_data/csr/openssl_cnf/CSR.csr" charset: @"utf-8"];
if (success == NO) {
    NSLog(@"%@",@"Failed to load CSR.csr");
    return;
}

CkoCsr *csr0 = [[CkoCsr alloc] init];
success = [csr0 LoadCsrPem: [sbCsr GetAsString]];
if (success == NO) {
    NSLog(@"%@",csr0.LastErrorText);
    return;
}

CkoXml *xml0 = [[CkoXml alloc] init];
success = [csr0 GetExtensionRequest: xml0];
if (success == NO) {
    NSLog(@"%@",csr0.LastErrorText);
    return;
}

// Let's examine the extension request..
NSLog(@"%@",[xml0 GetXml]);

// <?xml version="1.0" encoding="utf-8"?>
// <set>
//     <sequence>
//         <sequence>
//             <oid>1.3.6.1.4.1.311.20.2</oid>
//             <asnOctets>
//                 <printable>ZATCA-Code-Signing</printable>
//             </asnOctets>
//         </sequence>
//         <sequence>
//             <oid>2.5.29.17</oid>
//             <asnOctets>
//                 <sequence>
//                     <contextSpecific tag="4" constructed="1">
//                         <sequence>
//                             <set>
//                                 <sequence>
//                                     <oid>2.5.4.4</oid>
//                                     <utf8>1-ASC|2-V01|3-1234567890</utf8>
//                                 </sequence>
//                             </set>
//                             <set>
//                                 <sequence>
//                                     <oid>0.9.2342.19200300.100.1.1</oid>
//                                     <utf8>312345678900003</utf8>
//                                 </sequence>
//                             </set>
//                             <set>
//                                 <sequence>
//                                     <oid>2.5.4.12</oid>
//                                     <utf8>1100</utf8>
//                                 </sequence>
//                             </set>
//                             <set>
//                                 <sequence>
//                                     <oid>2.5.4.26</oid>
//                                     <utf8>Dammam</utf8>
//                                 </sequence>
//                             </set>
//                             <set>
//                                 <sequence>
//                                     <oid>2.5.4.15</oid>
//                                     <utf8>IT</utf8>
//                                 </sequence>
//                             </set>
//                         </sequence>
//                     </contextSpecific>
//                 </sequence>
//             </asnOctets>
//         </sequence>
//     </sequence>
// </set>

// If you wish to generate the above XML without going through the above steps, copy the XML into
// the online tool at https://tools.chilkat.io/xmlCreate

// Here is the generated code for the above XML:

CkoXml *xml = [[CkoXml alloc] init];
xml.Tag = @"set";
[xml UpdateChildContent: @"sequence|sequence|oid" value: @"1.3.6.1.4.1.311.20.2"];
[xml UpdateChildContent: @"sequence|sequence|asnOctets|printable" value: @"ZATCA-Code-Signing"];
[xml UpdateChildContent: @"sequence|sequence[1]|oid" value: @"2.5.29.17"];
[xml UpdateAttrAt: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific" autoCreate: YES attrName: @"tag" attrValue: @"4"];
[xml UpdateAttrAt: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific" autoCreate: YES attrName: @"constructed" attrValue: @"1"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set|sequence|oid" value: @"2.5.4.4"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set|sequence|utf8" value: @"1-ASC|2-V01|3-1234567890"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[1]|sequence|oid" value: @"0.9.2342.19200300.100.1.1"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[1]|sequence|utf8" value: @"312345678900003"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[2]|sequence|oid" value: @"2.5.4.12"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[2]|sequence|utf8" value: @"1100"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[3]|sequence|oid" value: @"2.5.4.26"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[3]|sequence|utf8" value: @"Dammam"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[4]|sequence|oid" value: @"2.5.4.15"];
[xml UpdateChildContent: @"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[4]|sequence|utf8" value: @"IT"];

// We'll need a new secp256k1 private key, so let's generate it.
CkoEcc *ecdsa = [[CkoEcc alloc] init];
CkoPrng *prng = [[CkoPrng alloc] init];
CkoPrivateKey *privKey = [[CkoPrivateKey alloc] init];
success = [ecdsa GenKey: @"secp256k1" prng: prng privKey: privKey];
if (success == NO) {
    NSLog(@"%@",ecdsa.LastErrorText);
    return;
}

NSLog(@"%@",@"Generated secp256k1 private key.");

// Use a new CSR object to generate a CSR with the private key and extension request.
CkoCsr *csr = [[CkoCsr alloc] init];

// Add the [dn] fields
//  [ dn ]
//  CN =EXAMPLE-CORP  				# Common Name
//  C=SA									# Country Code e.g SA
//  OU=HEAD-OFFICE							# Organization Unit Name
//  O=ASC									# Organization Name
csr.CommonName = @"EXAMPLE-CORP";
csr.Country = @"SA";
csr.CompanyDivision = @"HEAD-OFFICE";
csr.Company = @"ASC";

// Add the extension request to the CSR
[csr SetExtensionRequest: xml];

// Generate the CSR with the extension request
NSString *csrPem = [csr GenCsrPem: privKey];
if (csr.LastMethodSuccess == NO) {
    NSLog(@"%@",csr.LastErrorText);
    return;
}

NSLog(@"%@",csrPem);

// Sample output:

// -----BEGIN CERTIFICATE REQUEST-----
// MIIBuDCCAV8CAQAwSDEVMBMGA1UEAwwMRVhBTVBMRS1DT1JQMQswCQYDVQQGEwJT
// QTEUMBIGA1UECwwLSEVBRC1PRkZJQ0UxDDAKBgNVBAoMA0FTQzBWMBAGByqGSM49
// AgEGBSuBBAAKA0IABFI5rusr76HiJcMMr1r4L0B0BOAs6azLkt/RwHoT6A0xFRRt
// tulWT40tNhx3qJ4I5ePNgMceOEtuK1kMGVTovI6ggbcwgbQGCSqGSIb3DQEJDjGB
// pjCBozAhBgkrBgEEAYI3FAIEFBMSWkFUQ0EtQ29kZS1TaWduaW5nMH4GA1UdEQR3
// MHWkczBxMSEwHwYDVQQEDBgxLUFTQ3wyLVYwMXwzLTEyMzQ1Njc4OTAxHzAdBgoJ
// kiaJk/IsZAEBDA8zMTIzNDU2Nzg5MDAwMDMxDTALBgNVBAwMBDExMDAxDzANBgNV
// BBoMBkRhbW1hbTELMAkGA1UEDwwCSVQwCgYIKoZIzj0EAwIDRwAwRAIgJnbgpSGb
// diB+0M1VTqc1GU9sFsfnOvVN/8WhWRRxQIwCIF5eH9vgMgXyoU284X8Bx3dqOJ4q
// xashGWci87POxSvT
// -----END CERTIFICATE REQUEST-----