The bug happens only when connecting with SSL with client certificates.
Apparently if client certificates are used in TLS handshake,
private keys for cert should be loaded into named persistent
container.This is because AcquireCredentialsHandle is done partically
out-of-process in lsass.exe, and lsass wants to read private keys from disk
See discussion in https://github.com/dotnet/runtime/issues/23749
Schannel has legacy behavior for ephemeral keys, not involving lsass,
and this is why it worked for us so far, however there are limitations.
It appears to only use rsa_sha1 for signature verification, and newer
OpenSSL no longer allows SHA1 for it, and this ends up in
"algorithm mismatch" message from schannel.
The above is just my understanding of how it works, because there is no
real documentation, the conclusion is based on discussion in
https://github.com/dotnet/runtime/issues/23749
The fix:
So storing the key in persistent named container evidently fixes it,
and this is what is done in this patch. Care is takes to destroy
key container after key is no longer needed, to
avoid filling %AppData%\Roaming\Microsoft\Crypto\RSA with tiny encrypted
key files. Thus the "persistency window" of the key in container on disk
is only for duration of AcquireCredentialsHandle
- don't verify fingerprint twice
- pci->dwVersion (certificate version) needs to be increased by 1
- use MARIADB_TLS_VERIFY_UNKNOWN for unknown tls verification errors
Peer certificate validation:
Since version 3.4 peer certificate verification is enabled by default.
It can be disabled via `mysql_optionsv`, using option
MYSQL_OPT_SSL_VERIFY_SERVER_CERT:
my_bool verify= 0;
mysql_options(mariadb, MYSQL_OPT_SSL_VERIFY_SERVER_CERT, &verify);
Self signed certificates
If the client obtained a self signed peer certificate from MariaDB server
the verification will fail, with the following exceptions:
* If the connection between client and server is considered to be secure:, e.g.
* a unix_socket is used for client server communication
* hostname is localhost (Windows operating system), 127.0.0.1 or ::1
* a specified fingerprint matches the fingerprint of the peer certificate (see below)
* a client can verify the certificate using account password, it's possible if
* account has a password
* authentication plugin is "secure without TLS", that is, one of
mysql_native_password, ed25519 or parsec.
Fingerprint verification of the peer certificate
A fingerprint is a cryptographic hash (SHA-256, SHA-384 or SHA-512) of the peer
certificate's binary data. Even if the fingerprint matches, an expired or
revoked certificate will not be accepted.
For security reasons support for MD5 and SHA1 has been removed.
Technical details:
==================
- Peer certificate verification call was removed from ma_tls_connect, instead it
will be called directly after the handshake succeeded (my_auth.c)
- mysql->net.tls_self_signed_error was replaced by mysql->net.tls_verify_status which
contains the result of the peer certfificate verification:
The verification status can be obtained with mariadb_get_infov using new parameter
MARIADB_TLS_VERIFY_STATUS.
unsigned int tls_verify_status;
mariadb_get_infov(mysql, MARIADB_TLS_VERIFY_STATUS, &tls_verify_status);
The result is a combination of the following flags:
MARIADB_TLS_VERIFY_OK 0
MARIADB_TLS_VERIFY_TRUST 1
MARIADB_TLS_VERIFY_HOST 2
MARIADB_TLS_VERIFY_PERIOD 4
MARIADB_TLS_VERIFY_FINGERPRINT 8
MARIADB_TLS_VERIFY_REVOKED 16
MARIADB_TLS_VERIFY_UNKNOWN 32
- GnuTLS peer certificate verification callback was removed and replaced by
gnutls_verify_peers2() api function, so the peer certificate validation
will happen after handshake.
- OpenSSL implementation will no longer use SSL_verify_result to check the
validity of the peer certificate. Instead a callback function will be called
during the handshake, which collects all certificate validation errors.
- If the peer certificate is not trusted, hostname verification will be
skipped.
- Testing
Added new test tls, which implements a python based dummy server, which allows
to set different certificates and TLS options. Please note. that tests are
expected to fail, since the server doesn't support further steps like user
authentication etc. after the handshake. Prerequisite for running the tls test
is Python3.
wait_io_or_timeout() accepts milliseconds, while options has seconds,
since this is just plain MYSQL_OPT_READ_TIMEOUT/...
The one that has milliseconds are pvio->timeout[PVIO_*_TIMEOUT], so use
them.
Usually this is not a problem, but, in case of interrupt (i.e. signal -
EINTR) SSL_read() will return SSL_ERROR_WANT_READ/SSL_ERROR_WANT_WRITE,
and then wait_io_or_timeout() will be called, and timeout will be wrong,
may cause a failure.
1) Fix check if end was reached (<= instead of <), so last parameter will
not be ignored in case it is an empty string.
2) Empty strings will be passed as NULL`in _mariadb_set_conf_option.
SSL_{read,write}'s return values == 0 signify the operation was
unsuccessful, but here it's being treated as success. Other calls of
these functions already properly checks the return value.
Signed-off-by: Josh Hunt <johunt@akamai.com>
Before checking pending result sets in prepared statements,
we need to check if the connection was already closed or
resetted by checking stmt->mysql. In case of NULL we return
false, since there are no more pending result sets.
Added a new structure MARIADB_X509_INFO, which
contains information about servers certificate.
The information can be obtained via mysql_get_infov API
function:
MARIADB_X509_INFO *info;
mariadb_get_infov(mysql, MARIADB_TLS_PEER_CERT_INFO, &info);
Resetting a statement will result in an error, if another (different)
statement has a pending unbuffered result set (CR_COMMANDS_OUT_OF_SYNC).
Freeing a statement result set will return an error, if the statement
has no result set or was not executed (CR_STMT_NO_RESULT).
mysql_old_password is disabled by default (setting DISABLED YES),
but can be used if the plugin was added to the list of restricted
authentication plugins (via mysql_optionsv using option
MARIADB_OPT_RESTRICTED_AUTH).
With MDEV-30366, server now permit to send a result-set containing generated id and Affected rows for each bulk operation. This feature can be enabled with option MARIADB_OPT_BULK_UNIT_RESULTS when server supports it.
This reverts 395641549ac7..536d9e2b9e5b, in particular:
8dffd56936 MDEV-31857 enable MYSQL_OPT_SSL_VERIFY_SERVER_CERT by default
a99570c118 MDEV-31855 SSL cert validation protocol extension
9aa15e72a7 TLS fingerprint
and related commits
