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C

Decode Microsoft Graph ID Token

See more Microsoft Graph Examples

Demonstrates how to decode a Microsoft Graph ID token.

Chilkat C Downloads

C
#include <C_CkJsonObject.h>
#include <C_CkJwt.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObject jsonToken;
    HCkJwt jwt;
    const char *idToken;
    const char *jose;
    HCkJsonObject jsonHeader;
    const char *claims;
    HCkJsonObject jsonClaims;
    const char *ver;
    const char *iss;
    const char *s_sub;
    const char *aud;
    int exp;
    int iat;
    int nbf;
    const char *name;
    const char *preferred_username;
    const char *oid;
    const char *tid;
    const char *aio;

    success = FALSE;

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

    // In a previous example, we obtained a Microsoft Graph OAuth2 access token.
    // This example loads the JSON saved from the previous example and decodes the id_token.

    // Our Microsoft Graph OAuth2 token looks like this:

    // {
    //   "token_type": "Bearer",
    //   "scope": "openid profile User.ReadWrite Mail.ReadWrite Mail.Send Files.ReadWrite User.Read Calendars.ReadWrite Group.ReadWrite.All",
    //   "expires_in": 3600,
    //   "ext_expires_in": 3600,
    //   "access_token": "EwCQA8l6...0HhMKYwC",
    //   "refresh_token": "MCWulIvzi2yD0S...igEFn51mqcByhZtAJg",
    //   "id_token": "eyJ0eXAiOiJKV1...Q7lRDaR-7A",
    //   "expires_on": "1562862714"
    // }

    jsonToken = CkJsonObject_Create();
    success = CkJsonObject_LoadFile(jsonToken,"qa_data/tokens/microsoftGraph.json");
    if (success == FALSE) {
        printf("Failed to load the JSON file...\n");
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    // Use Chilkat's JWT API to examine the id_token..
    jwt = CkJwt_Create();
    idToken = CkJsonObject_stringOf(jsonToken,"id_token");

    // Extract the JOSE header..
    jose = CkJwt_getHeader(jwt,idToken);

    jsonHeader = CkJsonObject_Create();
    CkJsonObject_Load(jsonHeader,jose);
    CkJsonObject_putEmitCompact(jsonHeader,FALSE);
    printf("%s\n",CkJsonObject_emit(jsonHeader));

    // The JOSE header looks like this:

    // {
    //   "typ": "JWT",
    //   "alg": "RS256",
    //   "kid": "1LTMzakihiRla_8z2BEJVXeWMqo"
    // }

    claims = CkJwt_getPayload(jwt,idToken);

    jsonClaims = CkJsonObject_Create();
    CkJsonObject_Load(jsonClaims,claims);
    CkJsonObject_putEmitCompact(jsonClaims,FALSE);
    printf("%s\n",CkJsonObject_emit(jsonClaims));

    // The claims look like this:

    // {
    //   "ver": "2.0",
    //   "iss": "https://login.microsoftonline.com/9188040d-6c67-4c5b-b112-36a304b66dad/v2.0",
    //   "sub": "AAAAAAAAAAAAAAAAAAAAAHJFryd6Gydo-XtTd1nhUNQ",
    //   "aud": "18c456bd-db75-43fe-9724-9e5d821c68ff",
    //   "exp": 1562945513,
    //   "iat": 1562858813,
    //   "nbf": 1562858813,
    //   "name": "Matt Chilkat",
    //   "preferred_username": "matt@example.com",
    //   "oid": "00000000-0000-0000-3a33-fceb9b74cc15",
    //   "tid": "9188040d-6c67-4c5b-b112-36a304b66dad",
    //   "aio": "DfibJqKnWC1c0FS6G ... W6pvTrQuYzyq16ghY$"
    // }
    // 

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    // Get each of the claims..
    ver = CkJsonObject_stringOf(jsonClaims,"ver");
    iss = CkJsonObject_stringOf(jsonClaims,"iss");
    s_sub = CkJsonObject_stringOf(jsonClaims,"sub");
    aud = CkJsonObject_stringOf(jsonClaims,"aud");
    exp = CkJsonObject_IntOf(jsonClaims,"exp");
    iat = CkJsonObject_IntOf(jsonClaims,"iat");
    nbf = CkJsonObject_IntOf(jsonClaims,"nbf");
    name = CkJsonObject_stringOf(jsonClaims,"name");
    preferred_username = CkJsonObject_stringOf(jsonClaims,"preferred_username");
    oid = CkJsonObject_stringOf(jsonClaims,"oid");
    tid = CkJsonObject_stringOf(jsonClaims,"tid");
    aio = CkJsonObject_stringOf(jsonClaims,"aio");


    CkJsonObject_Dispose(jsonToken);
    CkJwt_Dispose(jwt);
    CkJsonObject_Dispose(jsonHeader);
    CkJsonObject_Dispose(jsonClaims);

    }