Expose `TPM2_ASN_TrimZeros`.

src/tpm2_asn.c

@@ -27,8 +27,6 @@
 
 #ifndef WOLFTPM2_NO_ASN
 
-#if defined(HAVE_ECC) && (defined(WOLFTPM_CRYPTOCB) || \
-   (defined(HAVE_PK_CALLBACKS) && !defined(WOLFCRYPT_ONLY)))
 /* Helper to trim leading zeros when not required  */
 byte* TPM2_ASN_TrimZeros(byte* in, word32* len)
 {
@@ -40,7 +38,6 @@ byte* TPM2_ASN_TrimZeros(byte* in, word32* len)
     *len -= idx;
     return in;
 }
-#endif
 
 int TPM2_ASN_GetLength_ex(const uint8_t* input, word32* inOutIdx, int* len,
                            word32 maxIdx, int check)

tests/unit_tests.c

@@ -397,7 +397,8 @@ static void test_wolfTPM2_CSR(void)
 #endif
 }
 
-#if !defined(WOLFTPM2_NO_WOLFCRYPT) && defined(HAVE_ECC)
+#if !defined(WOLFTPM2_NO_WOLFCRYPT) && defined(HAVE_ECC) && \
+    !defined(WOLFTPM2_NO_ASN)
 static void test_wolfTPM2_EccSignVerifyDig(const byte* digest, int digestSz,
     TPM_ECC_CURVE curve, TPMI_ALG_HASH hashAlg)
 {
@@ -829,7 +830,8 @@ int unit_tests(int argc, char *argv[])
     test_wolfTPM2_KeyBlob(TPM_ALG_ECC);
     test_wolfTPM2_Cleanup();
     test_wolfTPM2_thread_local_storage();
-    #if !defined(WOLFTPM2_NO_WOLFCRYPT) && defined(HAVE_ECC)
+    #if !defined(WOLFTPM2_NO_WOLFCRYPT) && defined(HAVE_ECC) && \
+        !defined(WOLFTPM2_NO_ASN)
     test_wolfTPM2_EccSignVerify();
     #endif
 #endif /* !WOLFTPM2_NO_WRAPPER */

wolftpm/tpm2_asn.h

@@ -80,8 +80,9 @@ typedef struct DecodedX509 {
     \param maxIdx Maximum allowed index in buffer
     \return Length on success, TPM_RC_INSUFFICIENT on buffer error
 */
-WOLFTPM_API int TPM2_ASN_GetLength(const uint8_t* input, word32* inOutIdx, int* len,
+WOLFTPM_API int TPM2_ASN_GetLength(const uint8_t* input, word32* inOutIdx,
-                           word32 maxIdx);
+    int* len, word32 maxIdx);
+
 /*!
     \ingroup ASN
     \brief Decodes ASN.1 length with optional length checking
@@ -92,8 +93,9 @@ WOLFTPM_API int TPM2_ASN_GetLength(const uint8_t* input, word32* inOutIdx, int*
     \param check Flag to enable length validation
     \return Length on success, TPM_RC_INSUFFICIENT on buffer error
 */
-WOLFTPM_API int TPM2_ASN_GetLength_ex(const uint8_t* input, word32* inOutIdx, int* len,
+WOLFTPM_API int TPM2_ASN_GetLength_ex(const uint8_t* input, word32* inOutIdx,
-                           word32 maxIdx, int check);
+    int* len, word32 maxIdx, int check);
+
 /*!
     \ingroup ASN
     \brief Decodes ASN.1 tag and validates length
@@ -104,15 +106,19 @@ WOLFTPM_API int TPM2_ASN_GetLength_ex(const uint8_t* input, word32* inOutIdx, in
     \param tag Expected ASN.1 tag value
     \return 0 on success, TPM_RC_INSUFFICIENT on buffer error, TPM_RC_VALUE on tag mismatch
 */
-WOLFTPM_API int TPM2_ASN_DecodeTag(const uint8_t* input, int inputSz, int* inOutIdx, int* tag_len, uint8_t tag);
+WOLFTPM_API int TPM2_ASN_DecodeTag(const uint8_t* input, int inputSz,
+    int* inOutIdx, int* tag_len, uint8_t tag);
+
 /*!
     \ingroup ASN
     \brief Decodes RSA signature from ASN.1 format
     \param pInput Pointer to buffer containing ASN.1 encoded RSA signature
     \param inputSz Size of input buffer
-    \return Size of decoded signature on success, TPM_RC_VALUE on invalid input, TPM_RC_INSUFFICIENT on buffer error
+    \return Size of decoded signature on success, TPM_RC_VALUE on invalid input,
+            TPM_RC_INSUFFICIENT on buffer error
 */
 WOLFTPM_API int TPM2_ASN_RsaDecodeSignature(uint8_t** pInput, int inputSz);
+
 /*!
     \brief Decodes an X.509 certificate
     \param input Buffer containing ASN.1 encoded X.509 certificate
@@ -120,28 +126,39 @@ WOLFTPM_API int TPM2_ASN_RsaDecodeSignature(uint8_t** pInput, int inputSz);
     \param x509 Structure to store decoded certificate data
     \return 0 on success, TPM_RC_VALUE on invalid input, TPM_RC_INSUFFICIENT on buffer error
 */
-WOLFTPM_API int TPM2_ASN_DecodeX509Cert(uint8_t* input, int inputSz, DecodedX509* x509);
+WOLFTPM_API int TPM2_ASN_DecodeX509Cert(uint8_t* input, int inputSz,
+    DecodedX509* x509);
+
 /*!
     \ingroup ASN
     \brief Decodes RSA public key from ASN.1 format into TPM2B_PUBLIC structure
     \param input Buffer containing ASN.1 encoded RSA public key
     \param inputSz Size of input buffer
     \param pub TPM2B_PUBLIC structure to store decoded key
-    \return 0 on success, TPM_RC_VALUE on invalid input, TPM_RC_INSUFFICIENT on buffer error
+    \return 0 on success, TPM_RC_VALUE on invalid input,
+        TPM_RC_INSUFFICIENT on buffer error
 */
-WOLFTPM_API int TPM2_ASN_DecodeRsaPubKey(uint8_t* input, int inputSz, TPM2B_PUBLIC* pub);
+WOLFTPM_API int TPM2_ASN_DecodeRsaPubKey(uint8_t* input, int inputSz,
+    TPM2B_PUBLIC* pub);
+
 /*!
     \ingroup ASN
     \brief Removes PKCS#1 v1.5 padding from RSA signature
-    \param pSig Pointer to buffer containing padded signature, updated to point to unpadded data
+    \param pSig Pointer to buffer containing padded signature, updated to point
+        to unpadded data
     \param sigSz Size of signature buffer, updated with unpadded size
     \return 0 on success, TPM_RC_VALUE on invalid padding
 */
 WOLFTPM_API int TPM2_ASN_RsaUnpadPkcsv15(uint8_t** pSig, int* sigSz);
 
-
+/*!
-WOLFTPM_LOCAL byte* TPM2_ASN_TrimZeros(byte* in, word32* len);
+    \ingroup ASN
-
+    \brief Removes leading zero bytes from a buffer
+    \param in Pointer to input buffer containing data to trim
+    \param len Pointer to length of input buffer, updated with new length after trimming
+    \return Pointer to the trimmed buffer (may be same as input if no trimming needed)
+*/
+WOLFTPM_API byte* TPM2_ASN_TrimZeros(byte* in, word32* len);
 
 #ifdef __cplusplus
     }  /* extern "C" */