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C

Signing HTTP Messages

See more RSA Examples

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

Chilkat C Downloads

C
#include <C_CkStringBuilder.h>
#include <C_CkPublicKey.h>
#include <C_CkPrivateKey.h>
#include <C_CkDateTime.h>
#include <C_CkRsa.h>

void ChilkatSample(void)
    {
    BOOL success;
    BOOL bCrlf;
    HCkStringBuilder sbPublicKeyPem;
    HCkPublicKey pubKey;
    HCkStringBuilder sbPrivateKeyPem;
    HCkPrivateKey privKey;
    HCkDateTime dtNow;
    const char *dateStr;
    HCkRsa rsa;
    HCkStringBuilder sbStringToSign;
    const char *b64Signature;

    success = FALSE;

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

    bCrlf = TRUE;
    sbPublicKeyPem = CkStringBuilder_Create();
    CkStringBuilder_AppendLine(sbPublicKeyPem,"-----BEGIN PUBLIC KEY-----",bCrlf);
    CkStringBuilder_AppendLine(sbPublicKeyPem,"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDCFENGw33yGihy92pDjZQhl0C3",bCrlf);
    CkStringBuilder_AppendLine(sbPublicKeyPem,"6rPJj+CvfSC8+q28hxA161QFNUd13wuCTUcq0Qd2qsBe/2hFyc2DCJJg0h1L78+6",bCrlf);
    CkStringBuilder_AppendLine(sbPublicKeyPem,"Z4UMR7EOcpfdUE9Hf3m/hs+FUR45uBJeDK1HSFHD8bHKD6kv8FPGfJTotc+2xjJw",bCrlf);
    CkStringBuilder_AppendLine(sbPublicKeyPem,"oYi+1hqp1fIekaxsyQIDAQAB",bCrlf);
    CkStringBuilder_AppendLine(sbPublicKeyPem,"-----END PUBLIC KEY-----",bCrlf);

    pubKey = CkPublicKey_Create();
    CkPublicKey_LoadFromString(pubKey,CkStringBuilder_getAsString(sbPublicKeyPem));

    sbPrivateKeyPem = CkStringBuilder_Create();
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"-----BEGIN RSA PRIVATE KEY-----",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"MIICXgIBAAKBgQDCFENGw33yGihy92pDjZQhl0C36rPJj+CvfSC8+q28hxA161QF",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"NUd13wuCTUcq0Qd2qsBe/2hFyc2DCJJg0h1L78+6Z4UMR7EOcpfdUE9Hf3m/hs+F",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"UR45uBJeDK1HSFHD8bHKD6kv8FPGfJTotc+2xjJwoYi+1hqp1fIekaxsyQIDAQAB",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"AoGBAJR8ZkCUvx5kzv+utdl7T5MnordT1TvoXXJGXK7ZZ+UuvMNUCdN2QPc4sBiA",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"QWvLw1cSKt5DsKZ8UETpYPy8pPYnnDEz2dDYiaew9+xEpubyeW2oH4Zx71wqBtOK",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"kqwrXa/pzdpiucRRjk6vE6YY7EBBs/g7uanVpGibOVAEsqH1AkEA7DkjVH28WDUg",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"f1nqvfn2Kj6CT7nIcE3jGJsZZ7zlZmBmHFDONMLUrXR/Zm3pR5m0tCmBqa5RK95u",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"412jt1dPIwJBANJT3v8pnkth48bQo/fKel6uEYyboRtA5/uHuHkZ6FQF7OUkGogc",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"mSJluOdc5t6hI1VsLn0QZEjQZMEOWr+wKSMCQQCC4kXJEsHAve77oP6HtG/IiEn7",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"kpyUXRNvFsDE0czpJJBvL/aRFUJxuRK91jhjC68sA7NsKMGg5OXb5I5Jj36xAkEA",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"gIT7aFOYBFwGgQAQkWNKLvySgKbAZRTeLBacpHMuQdl1DfdntvAyqpAZ0lY0RKmW",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"G6aFKaqQfOXKCyWoUiVknQJAXrlgySFci/2ueKlIE1QqIiLSZ8V8OlpFLRnb1pzI",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"7U1yQXnTAEFYM560yJlzUpOb1V4cScGd365tiSMvxLOvTA==",bCrlf);
    CkStringBuilder_AppendLine(sbPrivateKeyPem,"-----END RSA PRIVATE KEY-----",bCrlf);

    privKey = CkPrivateKey_Create();
    CkPrivateKey_LoadPem(privKey,CkStringBuilder_getAsString(sbPrivateKeyPem));

    //    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="
    // 

    dtNow = CkDateTime_Create();
    success = CkDateTime_SetFromCurrentSystemTime(dtNow);
    dateStr = CkDateTime_getAsRfc822(dtNow,FALSE);

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

    rsa = CkRsa_Create();
    success = CkRsa_UsePrivateKey(rsa,privKey);
    if (success == FALSE) {
        printf("%s\n",CkRsa_lastErrorText(rsa));
        CkStringBuilder_Dispose(sbPublicKeyPem);
        CkPublicKey_Dispose(pubKey);
        CkStringBuilder_Dispose(sbPrivateKeyPem);
        CkPrivateKey_Dispose(privKey);
        CkDateTime_Dispose(dtNow);
        CkRsa_Dispose(rsa);
        return;
    }

    sbStringToSign = CkStringBuilder_Create();
    CkStringBuilder_Append(sbStringToSign,"date: ");
    CkStringBuilder_Append(sbStringToSign,dateStr);

    CkRsa_putEncodingMode(rsa,"base64");
    b64Signature = CkRsa_signStringENC(rsa,CkStringBuilder_getAsString(sbStringToSign),"SHA256");
    printf("%s\n",b64Signature);
    printf("---------------------------\n");

    // 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="

    CkStringBuilder_Clear(sbStringToSign);
    CkStringBuilder_Append(sbStringToSign,"(request-target): ");
    CkStringBuilder_AppendLine(sbStringToSign,"post /foo?param=value&pet=dog",FALSE);
    CkStringBuilder_Append(sbStringToSign,"host: ");
    CkStringBuilder_AppendLine(sbStringToSign,"example.com",FALSE);
    CkStringBuilder_Append(sbStringToSign,"date: ");
    CkStringBuilder_Append(sbStringToSign,dateStr);

    printf("StringToSign:\n");
    printf("%s\n",CkStringBuilder_getAsString(sbStringToSign));
    b64Signature = CkRsa_signStringENC(rsa,CkStringBuilder_getAsString(sbStringToSign),"SHA256");
    printf("%s\n",b64Signature);
    printf("---------------------------\n");

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


    CkStringBuilder_Dispose(sbPublicKeyPem);
    CkPublicKey_Dispose(pubKey);
    CkStringBuilder_Dispose(sbPrivateKeyPem);
    CkPrivateKey_Dispose(privKey);
    CkDateTime_Dispose(dtNow);
    CkRsa_Dispose(rsa);
    CkStringBuilder_Dispose(sbStringToSign);

    }