From 34bfa15b21dbbfa2a82389d4b339e49db95dfd54 Mon Sep 17 00:00:00 2001 From: Gilles Peskine Date: Fri, 11 Jun 2021 16:25:36 +0200 Subject: [PATCH] Changelog entry for the mbedtls_mpi_read_xxx changes mbedtls_mpi_read_binary{,_le} (in https://github.com/ARMmbed/mbedtls/pull/4276) and mbedtls_mpi_read_string (in https://github.com/ARMmbed/mbedtls/pull/4644) changed their behavior on an empty input from constructing an MPI object with one limb to not allocating a limb. In principle, this change should be transparent to applications, however it caused a bug in the library and it does affect the value when writing back out, so list the change in the changelog. Signed-off-by: Gilles Peskine --- ChangeLog.d/mpi_read_zero.txt | 9 +++++++++ 1 file changed, 9 insertions(+) create mode 100644 ChangeLog.d/mpi_read_zero.txt diff --git a/ChangeLog.d/mpi_read_zero.txt b/ChangeLog.d/mpi_read_zero.txt new file mode 100644 index 000000000..0c25159d9 --- /dev/null +++ b/ChangeLog.d/mpi_read_zero.txt @@ -0,0 +1,9 @@ +Changes + * mbedtls_mpi_read_binary(), mbedtls_mpi_read_binary_le() and + mbedtls_mpi_read_string() now construct an mbedtls_mpi object with 0 limbs + when their input has length 0. Note that this is an implementation detail + and can change at any time, so this change should be transparent, but it + may result in mbedtls_mpi_write_binary() or mbedtls_mpi_write_string() + now writing an empty string where it previously wrote one or more + zero digits when operating from values constructed with an mpi_read + function and some mpi operations.