From 5b694428a9ee538b76636d7674de5f8a45bd7318 Mon Sep 17 00:00:00 2001
From: hong-revo <hongooi@microsoft.com>
Date: Wed, 13 Feb 2019 05:09:41 +1100
Subject: [PATCH] better presentation of common tokens

---
 R/format.R    |  9 ++++++++-
 R/normalize.R |  2 ++
 R/utils.R     | 23 +++++++++++++++++++++++
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/R/format.R b/R/format.R
index 44790cf..d860933 100644
--- a/R/format.R
+++ b/R/format.R
@@ -16,8 +16,15 @@ format_auth_header <- function(token)
 
     version <- if(token$version == 1) "v1.0" else "v2.0"
 
+    tenant <- token$tenant
+    if(tenant == "common")
+    {
+        token_obj <- decode_jwt(token$credentials$access_token)
+        tenant <- paste0(tenant, " / ", token_obj$payload$tid)
+    }
+
     paste0("Azure Active Directory ", version, " token for ", res, "\n",
-           "  Tenant: ", token$tenant, "\n",
+           "  Tenant: ", tenant, "\n",
            "  App ID: ", token$client$client_id, "\n",
            "  Authentication method: ", token$auth_type, "\n",
            "  Token valid from: ", format(obtained, usetz=TRUE), "  to: ", format(expiry, usetz=TRUE), "\n",
diff --git a/R/normalize.R b/R/normalize.R
index 34317e3..57010af 100644
--- a/R/normalize.R
+++ b/R/normalize.R
@@ -47,6 +47,8 @@
 #' @rdname guid
 normalize_tenant <- function(tenant)
 {
+    tenant <- tolower(tenant)
+
     # check if supplied a guid; if not, check if a fqdn;
     # if not, check if 'common'; if not, append '.onmicrosoft.com'
     if(is_guid(tenant))
diff --git a/R/utils.R b/R/utils.R
index 86ed84c..1017296 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -124,3 +124,26 @@ verify_v2_scope <- function(scope)
     scope
 }
 
+
+# decode info in a token (which is a JWT object)
+decode_jwt <- function(token)
+{
+    decode <- function(string)
+    {
+        m <- nchar(string) %% 4
+        if(m == 2)
+            string <- paste0(string, "==")
+        else if(m == 3)
+            string <- paste0(string, "=")
+        jsonlite::fromJSON(rawToChar(openssl::base64_decode(string)))
+    }
+
+    token <- as.list(strsplit(token, "\\.")[[1]])
+    token[1:2] <- lapply(token[1:2], decode)
+
+    names(token)[1:2] <- c("header", "payload")
+    if(length(token) > 2)
+        names(token)[3] <- "signature"
+
+    token
+}