From accf4437c654cf4740b1b78a9e12e5e4aae5ead9 Mon Sep 17 00:00:00 2001
From: Stefan Berger <stefanb@linux.vnet.ibm.com>
Date: Mon, 18 Nov 2019 10:40:29 -0500
Subject: [PATCH] tpm12: Implement TPM_PrintFourLimit to print 4 or less bytes

Implement TPM_PrintFourLimit to print only up to 4 bytes or less.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
---
 src/tpm12/tpm_debug.c | 48 +++++++++++++++++++++++++++++++++++--------
 src/tpm12/tpm_debug.h |  2 ++
 2 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/src/tpm12/tpm_debug.c b/src/tpm12/tpm_debug.c
index 7545dc41..da4347a6 100644
--- a/src/tpm12/tpm_debug.c
+++ b/src/tpm12/tpm_debug.c
@@ -57,17 +57,40 @@ int tpm_swallow_printf_args(const char *format, ...)
 
 #else
 
-/* TPM_PrintFour() prints a prefix plus 4 bytes of a buffer */
-
-void TPM_PrintFour(const char *string, const unsigned char* buff)
+void TPM_PrintFourLimit(const char *string,
+                        const unsigned char *buff, size_t buflen)
 {
     if (buff != NULL) {
-        TPMLIB_LogPrintf("%s %02x %02x %02x %02x\n",
-               string,
-               buff[0],
-               buff[1],
-               buff[2],
-               buff[3]);
+        switch (buflen) {
+        case 0:
+            TPMLIB_LogPrintf("%s (no data)\n", string);
+            break;
+        case 1:
+            TPMLIB_LogPrintf("%s %02x\n",
+                   string,
+                   buff[0]);
+            break;
+        case 2:
+            TPMLIB_LogPrintf("%s %02x %02x\n",
+                   string,
+                   buff[0],
+                   buff[1]);
+            break;
+        case 3:
+            TPMLIB_LogPrintf("%s %02x %02x %02x\n",
+                   string,
+                   buff[0],
+                   buff[1],
+                   buff[2]);
+            break;
+        default:
+            TPMLIB_LogPrintf("%s %02x %02x %02x %02x\n",
+                   string,
+                   buff[0],
+                   buff[1],
+                   buff[2],
+                   buff[3]);
+        }
     }
     else {
         TPMLIB_LogPrintf("%s null\n", string);
@@ -75,6 +98,13 @@ void TPM_PrintFour(const char *string, const unsigned char* buff)
     return;
 }
 
+/* TPM_PrintFour() prints a prefix plus 4 bytes of a buffer */
+
+void TPM_PrintFour(const char *string, const unsigned char* buff)
+{
+    TPM_PrintFourLimit(string, buff, 4);
+}
+
 #endif
 
 /* TPM_PrintAll() prints 'string', the length, and then the entire byte array
diff --git a/src/tpm12/tpm_debug.h b/src/tpm12/tpm_debug.h
index f2e75198..a9671d6a 100644
--- a/src/tpm12/tpm_debug.h
+++ b/src/tpm12/tpm_debug.h
@@ -46,6 +46,8 @@
 /* prototypes */
 
 void TPM_PrintFour(const char *string, const unsigned char* buff);
+void TPM_PrintFourLimit(const char *string,
+                        const unsigned char* buff, size_t bufflen);
 void TPM_PrintAll(const char *string, const unsigned char* buff, uint32_t length);
 
 #if 0