Add new mbedtls_pkcs5_pbe2_ext function
Add new mbedtls_pkcs5_pbe2_ext function to replace old
function with possible security issues.
Signed-off-by: Waleed Elmelegy <waleed.elmelegy@arm.com>
diff --git a/include/mbedtls/pkcs5.h b/include/mbedtls/pkcs5.h
index 40f5e67..b5c5446 100644
--- a/include/mbedtls/pkcs5.h
+++ b/include/mbedtls/pkcs5.h
@@ -95,6 +95,50 @@
const unsigned char *data, size_t datalen,
unsigned char *output);
+#if defined(MBEDTLS_CIPHER_PADDING_PKCS7)
+
+/**
+ * \brief PKCS#5 PBES2 function
+ *
+ * \warning When decrypting:
+ * - This function validates the CBC padding and returns
+ * #MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH if the padding is
+ * invalid. Note that this can help active adversaries
+ * attempting to brute-forcing the password. Note also that
+ * there is no guarantee that an invalid password will be
+ * detected (the chances of a valid padding with a random
+ * password are about 1/255).
+ *
+ * \param pbe_params the ASN.1 algorithm parameters
+ * \param mode either MBEDTLS_PKCS5_DECRYPT or MBEDTLS_PKCS5_ENCRYPT
+ * \param pwd password to use when generating key
+ * \param pwdlen length of password
+ * \param data data to process
+ * \param datalen length of data
+ * \param output Output buffer.
+ * On success, it contains the decrypted data, possibly
+ * followed by the CBC padding.
+ * On failure, the content is indetermidate.
+ * For decryption, there must be enough room for \p datalen
+ * bytes.
+ * For encryption, there must be enough room for
+ * \p datalen + 1 bytes, rounded up to the block size of
+ * the block cipher identified by \p pbe_params.
+ * \param output_size size of output buffer.
+ * This must be big enough to accommodate for output plus
+ * padding data.
+ * \param output_len length of actual data written to the output buffer.
+ *
+ * \returns 0 on success, or a MBEDTLS_ERR_XXX code if verification fails.
+ */
+int mbedtls_pkcs5_pbes2_ext(const mbedtls_asn1_buf *pbe_params, int mode,
+ const unsigned char *pwd, size_t pwdlen,
+ const unsigned char *data, size_t datalen,
+ unsigned char *output, size_t output_size,
+ size_t *output_len);
+
+#endif /* MBEDTLS_CIPHER_PADDING_PKCS7 */
+
#endif /* MBEDTLS_ASN1_PARSE_C */
/**