Remote storage: provide credentials for ssh based remotes

The key location is hard coded as this is only intended for our own
infrastructure, so we don't need multiple keys.

If the private key is protected by a passphrase, this needs to be manually
added to the preferences. As RemoteStorage->passphrase.

This has only be tested with a current version of libgit2 master, but
should compile with any previous version (the API doesn't exist in v0.19
and earlier - that's handled with appropriate #if clauses).

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 23 insertions, 2 deletions

diff --git a/git-access.c b/git-access.c
index 2b318e323..9feea0069 100644
--- a/git-access.c
+++ b/git-access.c
@@ -69,6 +69,19 @@ static int try_to_update(git_repository *rep, git_reference *local, git_referenc
 	return report_error("Local and remote do not match, not updating");
 }
 
+#if LIBGIT2_VER_MAJOR || LIBGIT2_VER_MINOR >= 20
+int credential_cb(git_cred **out,
+		  const char *url,
+		  const char *username_from_url,
+		  unsigned int allowed_types,
+		  void *payload)
+{
+	const char *priv_key = format_string("%s/%s", system_default_directory(), "ssrf_remote.key");
+	const char *passphrase = copy_string(prefs.passphrase);
+	return git_cred_ssh_key_new(out, username_from_url, NULL, priv_key, passphrase);
+}
+#endif
+
 static git_repository *update_local_repo(const char *localdir, const char *remote, const char *branch)
 {
 	int error;
@@ -95,7 +108,12 @@ static git_repository *update_local_repo(const char *localdir, const char *remot
 	}
 
 	// NOTE! A fetch error is not fatal, we just report it
-	error = git_remote_fetch(origin, NULL, NULL, NULL);
+	git_fetch_options opts = GIT_FETCH_OPTIONS_INIT;
+#if LIBGIT2_VER_MAJOR || LIBGIT2_VER_MINOR >= 20
+	if (strncmp(remote, "ssh://", 6) == 0)
+		opts.callbacks.credentials = credential_cb;
+#endif
+	error = git_remote_fetch(origin, NULL, &opts, NULL);
 	git_remote_free(origin);
 	if (error) {
 		report_error("Unable to update cache for remote '%s'", remote);
@@ -129,7 +147,10 @@ static git_repository *create_local_repo(const char *localdir, const char *remot
 	int error;
 	git_repository *cloned_repo = NULL;
 	git_clone_options opts = GIT_CLONE_OPTIONS_INIT;
-
+#if LIBGIT2_VER_MAJOR || LIBGIT2_VER_MINOR >= 20
+	if (strncmp(remote, "ssh://", 6) == 0)
+		opts.fetch_opts.callbacks.credentials = credential_cb;
+#endif
 	opts.checkout_branch = branch;
 	error = git_clone(&cloned_repo, remote, localdir, &opts);
 	if (error) {