1 files changed, 43 insertions, 0 deletions
diff --git a/internal/transport/signing.go b/internal/transport/signing.go
new file mode 100644
index 000000000..39896a2a8
--- /dev/null
+++ b/internal/transport/signing.go
@@ -0,0 +1,43 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package transport
+
+import (
+	"github.com/go-fed/httpsig"
+)
+
+var (
+	// http signer preferences
+	prefs       = []httpsig.Algorithm{httpsig.RSA_SHA256}
+	digestAlgo  = httpsig.DigestSha256
+	getHeaders  = []string{httpsig.RequestTarget, "host", "date"}
+	postHeaders = []string{httpsig.RequestTarget, "host", "date", "digest"}
+)
+
+// NewGETSigner returns a new httpsig.Signer instance initialized with GTS GET preferences.
+func NewGETSigner(expiresIn int64) (httpsig.Signer, error) {
+	sig, _, err := httpsig.NewSigner(prefs, digestAlgo, getHeaders, httpsig.Signature, expiresIn)
+	return sig, err
+}
+
+// NewPOSTSigner returns a new httpsig.Signer instance initialized with GTS POST preferences.
+func NewPOSTSigner(expiresIn int64) (httpsig.Signer, error) {
+	sig, _, err := httpsig.NewSigner(prefs, digestAlgo, postHeaders, httpsig.Signature, expiresIn)
+	return sig, err
+}