setopt: support certificate options in memory with struct curl_blob

This change introduces a generic way to provide binary data in setopt
options, called BLOBs.

This change introduces these new setopts:

CURLOPT_ISSUERCERT_BLOB, CURLOPT_PROXY_SSLCERT_BLOB,
CURLOPT_PROXY_SSLKEY_BLOB, CURLOPT_SSLCERT_BLOB and CURLOPT_SSLKEY_BLOB.

Reviewed-by: Daniel Stenberg
Closes #5357

1 files changed, 6 insertions, 4 deletions

diff --git a/docs/libcurl/opts/CURLOPT_SSLCERT.3 b/docs/libcurl/opts/CURLOPT_SSLCERT.3
index 4321e473f..4a43584c3 100644
--- a/docs/libcurl/opts/CURLOPT_SSLCERT.3
+++ b/docs/libcurl/opts/CURLOPT_SSLCERT.3
@@ -38,15 +38,17 @@ you wish to authenticate with as it is named in the security database. If you
 want to use a file from the current directory, please precede it with "./"
 prefix, in order to avoid confusion with a nickname.
 
-(Schannel only) Client certificates must be specified by a path expression to
-a certificate store. (Loading PFX is not supported; you can import it to a
-store first). You can use "<store location>\\<store name>\\<thumbprint>" to
-refer to a certificate in the system certificates store, for example,
+(Schannel only) Client certificates can be specified by a path expression to
+a certificate store. (You can import PFX to a store first). You can use
+"<store location>\\<store name>\\<thumbprint>" to refer to a certificate
+in the system certificates store, for example,
 "CurrentUser\\MY\\934a7ac6f8a5d579285a74fa61e19f23ddfe8d7a". Thumbprint is
 usually a SHA-1 hex string which you can see in certificate details. Following
 store locations are supported: CurrentUser, LocalMachine, CurrentService,
 Services, CurrentUserGroupPolicy, LocalMachineGroupPolicy,
 LocalMachineEnterprise.
+Schannel also support P12 certificate file, with the string "P12" specified
+with \fICURLOPT_SSLCERTTYPE(3)\fP.
 
 When using a client certificate, you most likely also need to provide a
 private key with \fICURLOPT_SSLKEY(3)\fP.