envoy: log mtls failures
This implements limited listener-based access logging for downstream
transport failures, only enabled when downstream_mtls.enforcement is
set to 'reject_connection'. Client certificate details and the error
message will be logged.
Additionally, the new key 'client-certificate' can be set in the
access_log_fields list in the configuration, which will add peer
certificate properties (issuer, subject, SANs) to the existing
per-request http logs.
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Co-authored-by: Kenneth Jenkins <51246568+kenjenkins@users.noreply.github.com>
* config: add customization options for logging
* config: validate log fields
* proxy: add support for logging http request headers
* log subset of headers
* add support for logging the http query
* fix test name
* use strings.Cut, add unit tests
* config: add customization options for logging
* config: validate log fields
* proxy: add support for logging http request headers
* log subset of headers
* fix test name
* dont use log.HTTPHeaders for access logs
* canonicalize http/2 headers
