mbedtls_md_setup() allocates a hash-specific context and then, if
requested, an extra HMAC context. If the second allocation failed, the
hash context was not freed.
Fix this by ensuring that the mbedtls_md_context_t object is always in
a consistent state, in particular, that the md_info field is always
set. For robustness, ensure that the object is in a consistent state
even on errors (other than BAD_INPUT_DATA if the object was not in a
consistent state on entry).
Fix#3486
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
As a result, the copyright of contributors other than Arm is now
acknowledged, and the years of publishing are no longer tracked in the
source files.
Also remove the now-redundant lines declaring that the files are part of
MbedTLS.
This commit was generated using the following script:
# ========================
#!/bin/sh
# Find files
find '(' -path './.git' -o -path './3rdparty' ')' -prune -o -type f -print | xargs sed -bi '
# Replace copyright attribution line
s/Copyright.*Arm.*/Copyright The Mbed TLS Contributors/I
# Remove redundant declaration and the preceding line
$!N
/This file is part of Mbed TLS/Id
P
D
'
# ========================
Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
In library source files, include "common.h", which takes care of
including "mbedtls/config.h" (or the alternative MBEDTLS_CONFIG_FILE)
and other things that are used throughout the library.
FROM=$'#if !defined(MBEDTLS_CONFIG_FILE)\n#include "mbedtls/config.h"\n#else\n#include MBEDTLS_CONFIG_FILE\n#endif' perl -i -0777 -pe 's~\Q$ENV{FROM}~#include "common.h"~' library/*.c 3rdparty/*/library/*.c scripts/data_files/error.fmt scripts/data_files/version_features.fmt
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
In the generic message digest abstraction, instead of storing method
pointers in the per-algorithm data structure and using wrapper
functions as those methods, call the per-algorithm function directly.
This saves some code size (2336B -> 2043B for md with all algorithms
enabled on M0+ with gcc -Os). This should also make it easier to
optimize the case when a single algorithm is supported. In addition,
this is a very slight security improvement since it removes one
opportunity for a buffer overflow to directly turn into letting the
attacker overwrite a pointer to a function pointer.
This commit does not modify the documented API. However, it removes
the possibility for users to define their own hash implementations and
use them by building their own md_info.
Changing mbedtls_md_context to contain a md type identifier rather
than a pointer to an info structure would save a few more bytes and a
few more runtime memory accesses, but would be a major API break since
a lot of code uses `const mbedtls_md_info *` to keep track of which
hash is in use.
This commit removes all the static occurrencies of the function
mbedtls_zeroize() in each of the individual .c modules. Instead the
function has been moved to utils.h that is included in each of the
modules.
Note from future self: actually md_init_ctx will be re-introduced with the
same signature later, and a new function with the additional argument will be
added.
- more freedom for us to change it in the future
- enforces hygiene
- performance impact of making accessors no longer inline should really be
negligible
