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C

URL Signing for Google Maps API

See more Encryption Examples

Demonstrates how to sign a URL for the Google Maps API.

Chilkat C Downloads

C
#include <C_CkCrypt2.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    const char *sig;

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

    crypt = CkCrypt2_Create();

    // The output will be modified Base64.
    // Modified Base64 for URLs replaces the '+' and '/' characters 
    // of standard Base64 with '-' and '_' respectively, so that these 
    // Base64 signatures no longer need to be URL-encoded.
    CkCrypt2_putEncodingMode(crypt,"modBase64");

    // Set the hash algorithm to sha-1
    CkCrypt2_putHashAlgorithm(crypt,"sha-1");
    CkCrypt2_putMacAlgorithm(crypt,"hmac");

    // Set the HMAC key (this is the private key provided by Google)
    CkCrypt2_SetMacKeyEncoded(crypt,"vNIXE0xscrmjlyV-12Nj_BvUPaw=","modBase64");

    // Compute the URL signature
    sig = CkCrypt2_macStringENC(crypt,"/maps/api/geocode/json?address=New+York&sensor=false&client=clientID");

    // The result should be KrU1TzVQM7Ur0i8i7K3huiw3MsA=
    printf("%s\n",sig);


    CkCrypt2_Dispose(crypt);

    }