Objective-C

Signing HTTP Messages

See more RSA Examples

Demonstrates how to sign HTTP messages per draft-cavage-http-signatures-10 Objective-C

#import <CkoStringBuilder.h>
#import <CkoPublicKey.h>
#import <CkoPrivateKey.h>
#import <CkoDateTime.h>
#import <NSString.h>
#import <CkoRsa.h>

BOOL success = NO;

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

BOOL bCrlf = YES;
CkoStringBuilder *sbPublicKeyPem = [[CkoStringBuilder alloc] init];
[sbPublicKeyPem AppendLine: @"-----BEGIN PUBLIC KEY-----" crlf: bCrlf];
[sbPublicKeyPem AppendLine: @"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDCFENGw33yGihy92pDjZQhl0C3" crlf: bCrlf];
[sbPublicKeyPem AppendLine: @"6rPJj+CvfSC8+q28hxA161QFNUd13wuCTUcq0Qd2qsBe/2hFyc2DCJJg0h1L78+6" crlf: bCrlf];
[sbPublicKeyPem AppendLine: @"Z4UMR7EOcpfdUE9Hf3m/hs+FUR45uBJeDK1HSFHD8bHKD6kv8FPGfJTotc+2xjJw" crlf: bCrlf];
[sbPublicKeyPem AppendLine: @"oYi+1hqp1fIekaxsyQIDAQAB" crlf: bCrlf];
[sbPublicKeyPem AppendLine: @"-----END PUBLIC KEY-----" crlf: bCrlf];

CkoPublicKey *pubKey = [[CkoPublicKey alloc] init];
[pubKey LoadFromString: [sbPublicKeyPem GetAsString]];

CkoStringBuilder *sbPrivateKeyPem = [[CkoStringBuilder alloc] init];
[sbPrivateKeyPem AppendLine: @"-----BEGIN RSA PRIVATE KEY-----" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"MIICXgIBAAKBgQDCFENGw33yGihy92pDjZQhl0C36rPJj+CvfSC8+q28hxA161QF" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"NUd13wuCTUcq0Qd2qsBe/2hFyc2DCJJg0h1L78+6Z4UMR7EOcpfdUE9Hf3m/hs+F" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"UR45uBJeDK1HSFHD8bHKD6kv8FPGfJTotc+2xjJwoYi+1hqp1fIekaxsyQIDAQAB" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"AoGBAJR8ZkCUvx5kzv+utdl7T5MnordT1TvoXXJGXK7ZZ+UuvMNUCdN2QPc4sBiA" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"QWvLw1cSKt5DsKZ8UETpYPy8pPYnnDEz2dDYiaew9+xEpubyeW2oH4Zx71wqBtOK" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"kqwrXa/pzdpiucRRjk6vE6YY7EBBs/g7uanVpGibOVAEsqH1AkEA7DkjVH28WDUg" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"f1nqvfn2Kj6CT7nIcE3jGJsZZ7zlZmBmHFDONMLUrXR/Zm3pR5m0tCmBqa5RK95u" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"412jt1dPIwJBANJT3v8pnkth48bQo/fKel6uEYyboRtA5/uHuHkZ6FQF7OUkGogc" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"mSJluOdc5t6hI1VsLn0QZEjQZMEOWr+wKSMCQQCC4kXJEsHAve77oP6HtG/IiEn7" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"kpyUXRNvFsDE0czpJJBvL/aRFUJxuRK91jhjC68sA7NsKMGg5OXb5I5Jj36xAkEA" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"gIT7aFOYBFwGgQAQkWNKLvySgKbAZRTeLBacpHMuQdl1DfdntvAyqpAZ0lY0RKmW" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"G6aFKaqQfOXKCyWoUiVknQJAXrlgySFci/2ueKlIE1QqIiLSZ8V8OlpFLRnb1pzI" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"7U1yQXnTAEFYM560yJlzUpOb1V4cScGd365tiSMvxLOvTA==" crlf: bCrlf];
[sbPrivateKeyPem AppendLine: @"-----END RSA PRIVATE KEY-----" crlf: bCrlf];

CkoPrivateKey *privKey = [[CkoPrivateKey alloc] init];
[privKey LoadPem: [sbPrivateKeyPem GetAsString]];

//     All examples use this request:
//  
//     POST /foo?param=value&pet=dog HTTP/1.1
//     Host: example.com
//     Date: Sun, 05 Jan 2014 21:31:40 GMT
//     Content-Type: application/json
//     Digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=
//     Content-Length: 18
//  
//     {"hello": "world"}

//  C.1.  Default Test
//  
//     If a list of headers is not included, the date is the only header
//     that is signed by default.  The string to sign would be:
//  
//     date: Sun, 05 Jan 2014 21:31:40 GMT
//  
//     The Authorization header would be:
//  
//     Authorization: Signature keyId="Test",algorithm="rsa-sha256",
//     signature="SjWJWbWN7i0wzBvtPl8rbASWz5xQW6mcJmn+ibttBqtifLN7Sazz
//     6m79cNfwwb8DMJ5cou1s7uEGKKCs+FLEEaDV5lp7q25WqS+lavg7T8hc0GppauB
//     6hbgEKTwblDHYGEtbGmtdHgVCk9SuS13F0hZ8FD0k/5OxEPXe5WozsbM="
//  
//     The Signature header would be:
//  
//     Signature: keyId="Test",algorithm="rsa-sha256",
//     signature="SjWJWbWN7i0wzBvtPl8rbASWz5xQW6mcJmn+ibttBqtifLN7Sazz
//     6m79cNfwwb8DMJ5cou1s7uEGKKCs+FLEEaDV5lp7q25WqS+lavg7T8hc0GppauB
//     6hbgEKTwblDHYGEtbGmtdHgVCk9SuS13F0hZ8FD0k/5OxEPXe5WozsbM="
//  

CkoDateTime *dtNow = [[CkoDateTime alloc] init];
success = [dtNow SetFromCurrentSystemTime];
NSString *dateStr = [dtNow GetAsRfc822: NO];

//  To duplicate the above result, we'll hard-code the date string.
dateStr = @"Sun, 05 Jan 2014 21:31:40 GMT";

CkoRsa *rsa = [[CkoRsa alloc] init];
success = [rsa UsePrivateKey: privKey];
if (success == NO) {
    NSLog(@"%@",rsa.LastErrorText);
    return;
}

CkoStringBuilder *sbStringToSign = [[CkoStringBuilder alloc] init];
[sbStringToSign Append: @"date: "];
[sbStringToSign Append: dateStr];

rsa.EncodingMode = @"base64";
NSString *b64Signature = [rsa SignStringENC: [sbStringToSign GetAsString] hashAlg: @"SHA256"];
NSLog(@"%@",b64Signature);
NSLog(@"%@",@"---------------------------");

//  The result should be:
//  SjWJWbWN7i0wzBvtPl8rbASW ... FD0k/5OxEPXe5WozsbM=

//  ----------------------------------------------------------------------------------------------------

//  C.2.  Basic Test
//  
//     The minimum recommended data to sign is the (request-target), host,
//     and date.  In this case, the string to sign would be:
//  
//     (request-target): post /foo?param=value&pet=dog
//     host: example.com
//     date: Sun, 05 Jan 2014 21:31:40 GMT
//  
//     The Authorization header would be:
//  
//     Authorization: Signature keyId="Test",algorithm="rsa-sha256",
//     headers="(request-target) host date", signature="qdx+H7PHHDZgy4
//     y/Ahn9Tny9V3GP6YgBPyUXMmoxWtLbHpUnXS2mg2+SbrQDMCJypxBLSPQR2aAjn
//     7ndmw2iicw3HMbe8VfEdKFYRqzic+efkb3nndiv/x1xSHDJWeSWkx3ButlYSuBs
//     kLu6kd9Fswtemr3lgdDEmn04swr2Os0="

[sbStringToSign Clear];
[sbStringToSign Append: @"(request-target): "];
[sbStringToSign AppendLine: @"post /foo?param=value&pet=dog" crlf: NO];
[sbStringToSign Append: @"host: "];
[sbStringToSign AppendLine: @"example.com" crlf: NO];
[sbStringToSign Append: @"date: "];
[sbStringToSign Append: dateStr];

NSLog(@"%@",@"StringToSign:");
NSLog(@"%@",[sbStringToSign GetAsString]);
b64Signature = [rsa SignStringENC: [sbStringToSign GetAsString] hashAlg: @"SHA256"];
NSLog(@"%@",b64Signature);
NSLog(@"%@",@"---------------------------");

//  The result should be:
//  qdx+H7PHHDZgy4y/Ahn ... mn04swr2Os0=