Allow use of TLS 1.3

Add a tlsv1.3 option to http.sslVersion in addition to the existing tlsv1.[012] options. libcurl has supported this since 7.52.0.

---
 Documentation/config.txt | 1 +
 http.c                   | 3 +++
 2 files changed, 4 insertions(+)

index ce9102cea..f31d62772 100644
@@ -1957,6 +1957,7 @@ http.sslVersion::
 	- tlsv1.0
 	- tlsv1.1
 	- tlsv1.2
+	- tlsv1.3
 
 +
 Can be overridden by the `GIT_SSL_VERSION` environment variable.

index a5bd5d62c..f84b18551 100644
@@ -62,6 +62,9 @@ static struct {
 	{ "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
 	{ "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
 #endif
+#if LIBCURL_VERSION_NUM >= 0x073400
+	{ "tlsv1.3", CURL_SSLVERSION_TLSv1_3 }
+#endif
 };
 #if LIBCURL_VERSION_NUM >= 0x070903
 static const char *ssl_key;

2.16.2

Hi Logan,

Can we *please* also add that OpenSSL 1.1.* is required (or that cURL is built with NSS or BoringSSL as the TLS backend)?

See
https://public-inbox.org/git/nycvar.QRO.7.76.6.1803240035300.77@ZVAVAG-6OXH6DA.rhebcr.pbec.zvpebfbsg.pbz/
for my original please.

I deem this information *really* important because a lot of Git packages are still built against OpenSSL 1.0.2 (e.g. Git for Windows) and *won't* benefit immediately from your patch.

Ciao,
Johannes

We might consider adding a way to extract that info from curl to make that work really good for you. There are now six TLS libraries that support TLS 1.3 and it might be hard for git to figure out the exact situation for each library and keep track of these moving targets...

 / daniel.haxx.se