Merge r1830819, r1830912, r1830913, r1830927, r1831168, r1831173, r1835240, r1835242...

Merge r1830819, r1830912, r1830913, r1830927, r1831168, r1831173, r1835240, r1835242, r1835615, r1836547 from trunk:

mod_ssl: Add support for loading private keys from ENGINEs.  Support
for PKCS#11 URIs only, and PIN entry is not threaded through
SSLPassPhraseDialog config yet.

* modules/ssl/ssl_util.c (modssl_is_engine_key): New function.

* modules/ssl/ssl_engine_config.c (ssl_cmd_SSLCertificateKeyFile):
  Use it, skip check for file existence for engine keys.

* modules/ssl/ssl_engine_pphrase.c (modssl_load_engine_pkey):
  New function.

* modules/ssl/ssl_engine_init.c (ssl_init_server_certs):
  For engine keys, load via modssl_load_engine_pkey.

* modules/ssl/ssl_util_ssl.c, modules/ssl/ssl_util_ssl.h:
  Remove modssl_read_encrypted_pkey() and helpers, added in r1804087
  but never used.

* modules/ssl/ssl_util_ssl.c (modssl_read_privatekey): Remove unused
  second argument.

* modules/ssl/ssl_engine_pphrase.c (ssl_load_encrypted_pkey): Adjust
  accordingly.

Simplify the ssl_asn1_table API, remove abstraction (it is used only
to cache serialized EVP_PKEYs not any char * blobs), and document.

* modules/ssl/ssl_util.c (ssl_asn1_table_set): Take the EVP_PKEY and
  serialize internally.  Use ap_realloc.  Return the ssl_asn1_t *
  pointer.  Don't call apr_hash_set() for unchanged pointer case.

* modules/ssl/ssl_engine_pphrase.c (ssl_load_encrypted_pkey):
  Adjust for the above.

* modules/ssl/ssl_private.h: Adjust as above, add docs.

mod_ssl: Add support for loading TLS certificates through the PKCS#11
engine.

* modules/ssl/ssl_util.c (modssl_is_engine_id): Renamed
  from modssl_is_engine_key.

* modules/ssl/ssl_engine_config.c (ssl_cmd_SSLCertificateKeyFile):
  Adjust accordingly.
  (ssl_cmd_SSLCertificateFile): Also allow ENGINE cert ids.

* modules/ssl/ssl_engine_pphrase.c (modssl_load_engine_keypair):
  Rename from modssl_load_engine_key; load certificate if
  cert id is passed.

* modules/ssl/ssl_engine_init.c (ssl_init_server_certs): Optionally
  load the certificate from the engine as well.

* docs/manual/: Update manual.

* modules/ssl/ssl_engine_init.c (ssl_init_server_certs): Add error
  logno. Free EVP_PKEY in engine case.  Never try reading ECDH/DH
  parameters from engine ids.

Hook up PKCS#11 PIN entry through configured passphrase entry method.

* modules/ssl/ssl_engine_pphrase.c: Add wrappers for OpenSSL UI * API
  around passphrase entry.
  (modssl_load_engine_keypair): Take vhost ID and use above rather than
  default OpenSSL UI.

* modules/ssl/ssl_engine_init.c (ssl_init_server_certs): Pass vhost ID.

Submitted by: Anderson Sasaki<ansaski redhat.com>, jorton

* modules/ssl/ssl_engine_pphrase.c: Add logno tags.

* modules/ssl/ssl_engine_pphrase.c (modssl_load_engine_keypair): Load
  the engine associated with the private key (&cert) explicitly
  rather than requiring the engine to be set as the default method
  for all operations (with "SSLCryptoDevice <engine>").

(Thanks to Anderson Sasaki <ansasaki redhat.com> for suggested
improvement and guidance)

* modules/ssl/ssl_engine_pphrase.c: Fix linking against OpenSSL without
  ENGINE support.

Submitted by: Anderson Sasaki <ansasaki redhat.com>, jorton
Reviewed by: jorton, jim, ylavic
Github: closes #92

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1874196 13f79535-47bb-0310-9956-ffa450edef68