NetworkPkg/IScsiDxe: assert that IScsiBinToHex() always succeeds

IScsiBinToHex() is called for encoding:

- the answer to the target's challenge; that is, CHAP_R;

- the challenge for the target, in case mutual authentication is enabled;
  that is, CHAP_C.

The initiator controls the size of both blobs, the sizes of their hex
encodings are correctly calculated in "RspLen" and "ChallengeLen".
Therefore the IScsiBinToHex() calls never fail; assert that.

Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3356
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Message-Id: <20210608121259.32451-7-lersek@redhat.com>
diff --git a/NetworkPkg/IScsiDxe/IScsiCHAP.c b/NetworkPkg/IScsiDxe/IScsiCHAP.c
index 9e192ce..dbe3c8e 100644
--- a/NetworkPkg/IScsiDxe/IScsiCHAP.c
+++ b/NetworkPkg/IScsiDxe/IScsiCHAP.c
@@ -391,6 +391,7 @@
   UINT32                      RspLen;

   CHAR8                       *Challenge;

   UINT32                      ChallengeLen;

+  EFI_STATUS                  BinToHexStatus;

 

   ASSERT (Conn->CurrentStage == ISCSI_SECURITY_NEGOTIATION);

 

@@ -471,12 +472,13 @@
     //

     // CHAP_R=<R>

     //

-    IScsiBinToHex (

-      (UINT8 *) AuthData->CHAPResponse,

-      ISCSI_CHAP_RSP_LEN,

-      Response,

-      &RspLen

-      );

+    BinToHexStatus = IScsiBinToHex (

+                       (UINT8 *) AuthData->CHAPResponse,

+                       ISCSI_CHAP_RSP_LEN,

+                       Response,

+                       &RspLen

+                       );

+    ASSERT_EFI_ERROR (BinToHexStatus);

     IScsiAddKeyValuePair (Pdu, ISCSI_KEY_CHAP_RESPONSE, Response);

 

     if (AuthData->AuthConfig->CHAPType == ISCSI_CHAP_MUTUAL) {

@@ -490,12 +492,13 @@
       // CHAP_C=<C>

       //

       IScsiGenRandom ((UINT8 *) AuthData->OutChallenge, ISCSI_CHAP_RSP_LEN);

-      IScsiBinToHex (

-        (UINT8 *) AuthData->OutChallenge,

-        ISCSI_CHAP_RSP_LEN,

-        Challenge,

-        &ChallengeLen

-        );

+      BinToHexStatus = IScsiBinToHex (

+                         (UINT8 *) AuthData->OutChallenge,

+                         ISCSI_CHAP_RSP_LEN,

+                         Challenge,

+                         &ChallengeLen

+                         );

+      ASSERT_EFI_ERROR (BinToHexStatus);

       IScsiAddKeyValuePair (Pdu, ISCSI_KEY_CHAP_CHALLENGE, Challenge);

 

       Conn->AuthStep = ISCSI_CHAP_STEP_FOUR;