This helps to prevent confusion as it avoids overloading the word
"copy" as both an action and an object.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
This helps to prevent confusion as it avoids overloading the word
"copy" as both an action and an object.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
When we are copying output, it makes sense to return
PSA_ERROR_BUFFER_TOO_SMALL since the buffer we are copying to is a user
output buffer.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Change psa_crypto_output_copy_free() to use psa_crypto_copy_output()
rather than calling memcpy directly as was erroneously done previously.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
This tied input and output buffers together in
awkward pairs, which made the API more difficult
to use.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Since we are internal rather than user-facing,
PSA_ERROR_CORRUPTION_DETECTED makes more sense than
PSA_ERROR_BUFFER_TOO_SMALL. Whilst it really is a buffer that is too
small, this error code is intended to indicate that a user-supplied
buffer is too small, not an internal one.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Zero-length buffers should be represented in the
psa_crypto_buffer_copy_t struct as NULL if it was created in
psa_crypto_alloc_and_copy(), so reject non-NULL zero-length buffers.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
If we have a copy buffer but no original to copy back to, there is not
much sensible we can do. The psa_crypto_buffer_copy_t state is invalid.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
Since it is implementation-dependent whether
malloc(0) returns NULL or a pointer, explicitly
represent zero-length buffers as NULL in the
buffer-copy struct, so as to have a uniform
behaviour.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
"Fix PBKDF2 with empty salt on platforms where malloc(0)=NULL" took care of
making an empty salt work. But it didn't fix the case of an empty salt
segment followed by a non-empty salt segment, which still invoked memcpy
with a potentially null pointer as the source. This commit fixes that case,
and also simplifies the logic in the function a little.
Test data obtained with:
```
pip3 install cryptodome
python3 -c 'import sys; from Crypto.Hash import SHA256; from Crypto.Protocol.KDF import PBKDF2; cost = int(sys.argv[1], 0); salt = bytes.fromhex(sys.argv[2]); password = bytes.fromhex(sys.argv[3]); n = int(sys.argv[4], 0); print(PBKDF2(password=password, salt=salt, dkLen=n, count=cost, hmac_hash_module=SHA256).hex())' 1 "" "706173737764" 64
```
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
