Make mcrypt input handling stricter #610
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Previously, if the size of the IV did not match the block size mcrypt would throw a warning and fall back to a NUL IV. This behavior is both dangerous and makes no practical sense. mcrypt_encrypt etc. will now return false if the IV has an incorrect size.
Previously the code fell back on using a NUL IV if no IV was passed and the encryption mode required it. This is dangerous and makes no sense from a practical point of view (as you could just as well use ECB then).
Previously an incorrectly sized key was either silently padded with NUL bytes or truncated. Especially the silent nature of this behavior makes it extremely easy to use weak encryption. A common mistake - which has also been extensively made in our tests - is to use a password instead of a key. Incorrectly sized keys will now be rejected.
Avoid unnecessary alloc/copy/free cycles and clean up structure in general. Add a few extra checks for the key length.
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| int count, i; | ||
| int *key_sizes = mcrypt_enc_get_supported_key_sizes(td, &count); |
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Seems a bit pointless to start a new scope here. Just put the definitions at the start?
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Comment on behalf of nikic at php.net: Merged. |
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No longer allow invalid IV size, invalid key size or missing IV on modes that require an IV.