Changelog entry for the MBEDTLS_CIPHER_BLKSIZE_MAX deprecation
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/ChangeLog.d/MBEDTLS_CIPHER_BLKSIZE_MAX.txt b/ChangeLog.d/MBEDTLS_CIPHER_BLKSIZE_MAX.txt
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+New deprecations
+ * MBEDTLS_CIPHER_BLKSIZE_MAX is deprecated in favor of
+ MBEDTLS_MAX_BLOCK_LENGTH (if you intended what the name suggests:
+ maximum size of any supported block cipher) or the new name
+ MBEDTLS_CMAC_MAX_BLOCK_SIZE (if you intended the actual semantics:
+ maximum size of a block cipher supported by the CMAC module).
+
+Security
+ * In configurations with ARIA or Camellia but not AES, the value of
+ MBEDTLS_CIPHER_BLKSIZE_MAX was 8, rather than 16 as the name might
+ suggest. This did not affect any library code, because this macro was
+ only used in relation with CMAC which does not support these ciphers.
+ This may affect application code that uses this macro.