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Objective-C

Generate CSR with Uncommon Fields

See more CSR Examples

Demonstrates how to generate a new RSA key and a Certificate Signing Request (CSR) for this:
csr.common.name=Admin forInformation-MainShop
csr.serial.number=1-XYZ|2-2.0|3-999695
csr.organization.identifier=990099994100099
csr.organization.unit.name=9999910000
csr.organization.name=9999910000
csr.country.name=SA
csr.invoice.type=1100
csr.location.address=King Fahed Road
csr.industry.business.category=MainOffice

Chilkat Objective-C Downloads

Objective-C
#import <CkoRsa.h>
#import <CkoPrivateKey.h>
#import <CkoCsr.h>
#import <NSString.h>
#import <CkoFileAccess.h>

BOOL success = NO;

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

// First generate an RSA private key.
CkoRsa *rsa = [[CkoRsa alloc] init];

// Generate a random 2048-bit RSA key.
CkoPrivateKey *privKey = [[CkoPrivateKey alloc] init];
success = [rsa GenKey: [NSNumber numberWithInt: 2048] privKey: privKey];
if (success == NO) {
    NSLog(@"%@",rsa.LastErrorText);
    return;
}

// Create the CSR object and set properties.
CkoCsr *csr = [[CkoCsr alloc] init];

csr.CommonName = @"Admin forInformation-MainShop";

// Country Name (2 letter code)
csr.Country = @"SA";

// Organization Name (eg, company)
csr.Company = @"9999910000";

// Organizational Unit Name (eg, secion/division)
csr.CompanyDivision = @"9999910000";

// See https://www.alvestrand.no/objectid/2.5.4.html for OIDs for the following fields:

// csr.serial.number=1-XYZ|2-2.0|3-999695
// 2.5.4.5 - id-at-serialNumber 
[csr SetSubjectField: @"2.5.4.5" value: @"1-XYZ|2-2.0|3-999695" asnType: @"UTF8String"];

// csr.organization.identifier=990099994100099
// 2.5.4.45 - id-at-uniqueIdentifier   Don't know if this is correct.
[csr SetSubjectField: @"2.5.4.45" value: @"1100" asnType: @"UTF8String"];

// csr.invoice.type=1100
// Don't know what this OID would be...
[csr SetSubjectField: @"2.5.4.99" value: @"1100" asnType: @"UTF8String"];

// csr.location.address=King Fahed Road
// 2.5.4.9 - id-at-streetAddress 
[csr SetSubjectField: @"2.5.4.9" value: @"King Fahed Road" asnType: @"UTF8String"];

// csr.industry.business.category=MainOffice
// 2.5.4.15 - id-at-businessCategory 
[csr SetSubjectField: @"2.5.4.15" value: @"MainOffice" asnType: @"UTF8String"];

// Create the CSR using the private key.
NSString *pemStr = [csr GenCsrPem: privKey];
if (csr.LastMethodSuccess != YES) {
    NSLog(@"%@",csr.LastErrorText);
    return;
}

// Save the private key and CSR to a files.
[privKey SavePkcs8EncryptedPemFile: @"password" path: @"qa_output/privKey1.pem"];

CkoFileAccess *fac = [[CkoFileAccess alloc] init];
[fac WriteEntireTextFile: @"qa_output/csr1.pem" fileData: pemStr charset: @"utf-8" includePreamble: NO];

// Show the CSR.
NSLog(@"%@",pemStr);

// Sample output:
// The CSR PEM can be checked here:
// https://www.networking4all.com/en/support/tools/csr+check/
// Copy-and-paste the PEM into the online CSR Decoding / CSR Verification form

// 	-----BEGIN CERTIFICATE REQUEST-----
// 	MIIC6jCCAdICAQAwgaQxITAfBgNVBAMMGG15c3ViZG9tYWluLm15ZG9tYWluLmNv
// ...
// ...
// 	hJnYCvjzFz4O9VtT+JtP9ldRHWV3KpZ8ne3AjD+F
// 	-----END CERTIFICATE REQUEST-----