pgcrypto: Detect errors with EVP calls from OpenSSL
The following routines are called within pgcrypto when handling digests
but there were no checks for failures:
- EVP_MD_CTX_size (can fail with -1 as of 3.0.0)
- EVP_MD_CTX_block_size (can fail with -1 as of 3.0.0)
- EVP_DigestInit_ex
- EVP_DigestUpdate
- EVP_DigestFinal_ex
A set of elog(ERROR) is added by this commit to detect such failures,
that should never happen except in the event of a processing failure
internal to OpenSSL.
Note that it would be possible to use ERR_reason_error_string() to get
more context about such errors, but these refer mainly to the internals
of OpenSSL, so it is not really obvious how useful that would be. This
is left out for simplicity.
Per report from Coverity. Thanks to Tom Lane for the discussion.
Backpatch-through: 9.5
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/28d1601ad988790c3c53d7ffd24ef6d2366d4457
Modified Files
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contrib/pgcrypto/openssl.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)
