From c1c7c903458b83a9e4ec0bcf01ba65e80805b617 Mon Sep 17 00:00:00 2001
From: toddouska <todd@wolfssl.com>
Date: Wed, 1 Mar 2017 11:17:24 -0800
Subject: [PATCH 1/2] add defined for default AES AUTH_TAG_MIN_SZ

---
 wolfcrypt/src/aes.c          | 10 ++++++++++
 wolfcrypt/test/test.c        | 26 --------------------------
 wolfssl/wolfcrypt/settings.h |  6 ++++++
 3 files changed, 16 insertions(+), 26 deletions(-)

diff --git a/wolfcrypt/src/aes.c b/wolfcrypt/src/aes.c
index 09c78bd4e..7b8c4b40a 100644
--- a/wolfcrypt/src/aes.c
+++ b/wolfcrypt/src/aes.c
@@ -4238,6 +4238,11 @@ int wc_AesGcmEncrypt(Aes* aes, byte* out, const byte* in, word32 sz,
     uint32_t keySize;
     status_t status;
 
+    if (authTagSz < WOLFSSL_MIN_AUTH_TAG_SZ) {
+        WOLFSSL_MSG("GcmEncrypt authTagSz too small error");
+        return BAD_FUNC_ARG;
+    }
+
     key = (byte*)aes->key;
 
     status = wc_AesGetKeySize(aes, &keySize);
@@ -4265,6 +4270,11 @@ int wc_AesGcmEncrypt(Aes* aes, byte* out, const byte* in, word32 sz,
     if (authTagSz > AES_BLOCK_SIZE)
         return BAD_FUNC_ARG;
 
+    if (authTagSz < WOLFSSL_MIN_AUTH_TAG_SZ) {
+        WOLFSSL_MSG("GcmEncrypt authTagSz too small error");
+        return BAD_FUNC_ARG;
+    }
+
 #ifdef WOLFSSL_AESNI
     if (haveAESNI) {
         AES_GCM_encrypt(in, out, authIn, iv, authTag,
diff --git a/wolfcrypt/test/test.c b/wolfcrypt/test/test.c
index 24aaaecc8..2e0cebb5a 100644
--- a/wolfcrypt/test/test.c
+++ b/wolfcrypt/test/test.c
@@ -3432,26 +3432,6 @@ int gmac_test(void)
         0x8d, 0x83, 0xb0, 0xbb, 0x14, 0xb6, 0x91
     };
 
-    const byte k3[] =
-    {
-        0xb8, 0xe4, 0x9a, 0x5e, 0x37, 0xf9, 0x98, 0x2b,
-        0xb9, 0x6d, 0xd0, 0xc9, 0xb6, 0xab, 0x26, 0xac
-    };
-    const byte iv3[] =
-    {
-        0xe4, 0x4a, 0x42, 0x18, 0x8c, 0xae, 0x94, 0x92,
-        0x6a, 0x9c, 0x26, 0xb0
-    };
-    const byte a3[] =
-    {
-        0x9d, 0xb9, 0x61, 0x68, 0xa6, 0x76, 0x7a, 0x31,
-        0xf8, 0x29, 0xe4, 0x72, 0x61, 0x68, 0x3f, 0x8a
-    };
-    const byte t3[] =
-    {
-        0x23, 0xe2, 0x9f, 0x66, 0xe4, 0xc6, 0x52, 0x48
-    };
-
     byte tag[16];
 
     XMEMSET(tag, 0, sizeof(tag));
@@ -3466,12 +3446,6 @@ int gmac_test(void)
     if (XMEMCMP(t2, tag, sizeof(t2)) != 0)
         return -127;
 
-    XMEMSET(tag, 0, sizeof(tag));
-    wc_GmacSetKey(&gmac, k3, sizeof(k3));
-    wc_GmacUpdate(&gmac, iv3, sizeof(iv3), a3, sizeof(a3), tag, sizeof(t3));
-    if (XMEMCMP(t3, tag, sizeof(t3)) != 0)
-        return -128;
-
     return 0;
 }
 #endif /* HAVE_AESGCM */
diff --git a/wolfssl/wolfcrypt/settings.h b/wolfssl/wolfcrypt/settings.h
index e1c93cd75..e8d7f1fc9 100644
--- a/wolfssl/wolfcrypt/settings.h
+++ b/wolfssl/wolfcrypt/settings.h
@@ -1396,6 +1396,12 @@ static char *fgets(char *buff, int sz, FILE *fp)
     #define NO_OLD_TLS
 #endif
 
+
+/* Default AES minimum auth tag sz, allow user to override */
+#ifndef WOLFSSL_MIN_AUTH_TAG_SZ
+    #define WOLFSSL_MIN_AUTH_TAG_SZ 12
+#endif
+
 /* If not forcing ARC4 as the DRBG or using custom RNG block gen, enable Hash_DRBG */
 #undef HAVE_HASHDRBG
 #if !defined(WOLFSSL_FORCE_RC4_DRBG) && !defined(CUSTOM_RAND_GENERATE_BLOCK)

From a348898e96b46d5edb595180f0df7bf3d9be7c1d Mon Sep 17 00:00:00 2001
From: toddouska <todd@wolfssl.com>
Date: Fri, 3 Mar 2017 11:42:24 -0800
Subject: [PATCH 2/2] add AUTH_SZ size check to ti and armv8 ports

---
 wolfcrypt/src/port/arm/armv8-aes.c | 5 +++++
 wolfcrypt/src/port/ti/ti-aes.c     | 3 +++
 2 files changed, 8 insertions(+)

diff --git a/wolfcrypt/src/port/arm/armv8-aes.c b/wolfcrypt/src/port/arm/armv8-aes.c
index e59bd2571..c189b3eda 100644
--- a/wolfcrypt/src/port/arm/armv8-aes.c
+++ b/wolfcrypt/src/port/arm/armv8-aes.c
@@ -2532,6 +2532,11 @@ int wc_AesGcmEncrypt(Aes* aes, byte* out, const byte* in, word32 sz,
         return BAD_FUNC_ARG;
     }
 
+    if (authTagSz < WOLFSSL_MIN_AUTH_TAG_SZ) {
+        WOLFSSL_MSG("GcmEncrypt authTagSz too small error");
+        return BAD_FUNC_ARG;
+    }
+
     switch (aes->rounds) {
         case 10:
             return Aes128GcmEncrypt(aes, out, in, sz, iv, ivSz,
diff --git a/wolfcrypt/src/port/ti/ti-aes.c b/wolfcrypt/src/port/ti/ti-aes.c
index 5b982c41d..cd8d2eed9 100644
--- a/wolfcrypt/src/port/ti/ti-aes.c
+++ b/wolfcrypt/src/port/ti/ti-aes.c
@@ -490,6 +490,9 @@ WOLFSSL_API int  wc_AesGcmEncrypt(Aes* aes, byte* out, const byte* in, word32 sz
                               byte* authTag, word32 authTagSz,
                               const byte* authIn, word32 authInSz)
 {
+    if (authTagSz < WOLFSSL_MIN_AUTH_TAG_SZ) {
+        return BAD_FUNC_ARG;
+    }
     return AesAuthEncrypt(aes, out, in, sz, iv, ivSz, authTag, authTagSz,
                               authIn, authInSz, AES_CFG_MODE_GCM_HY0CALC) ;
 }