More attempt at getting this shit to work

web/shared/clientRfc9421.go

@@ -0,0 +1,56 @@
+package webshared
+
+import (
+	"crypto/x509"
+	"io"
+	"net/http"
+
+	"github.com/yaronf/httpsign"
+
+	"git.mstar.dev/mstar/linstrom/config"
+)
+
+/*
+Links for home:
+- https://pkg.go.dev/github.com/yaronf/httpsign#Client.Do
+- https://www.ietf.org/archive/id/draft-richanna-http-message-signatures-00.html
+- https://github.com/mastodon/mastodon/issues/29905
+- https://github.com/fedify-dev/fedify/issues/208
+- https://github.com/mastodon/mastodon/issues/21429
+- https://github.com/go-ap/fedbox/blob/master/httpsig.go
+- https://swicg.github.io/activitypub-http-signature/
+- https://datatracker.ietf.org/doc/html/rfc9421
+*/
+
+func RequestSigned(
+	method, target string,
+	body io.Reader,
+	keyId string,
+	privateKeyBytes []byte,
+) (*http.Response, error) {
+	req, err := http.NewRequest(method, target, body)
+	if err != nil {
+		return nil, err
+	}
+	var signer *httpsign.Signer
+	signerFields := httpsign.Headers("@request-target", "content-digest")
+	if config.GlobalConfig.Experimental.UseEd25519Keys {
+		signer, err = httpsign.NewEd25519Signer(
+			privateKeyBytes,
+			httpsign.NewSignConfig(),
+			signerFields,
+		)
+	} else {
+		key, err := x509.ParsePKCS1PrivateKey(privateKeyBytes)
+		if err != nil {
+			return nil, err
+		}
+		signer, err = httpsign.NewRSASigner(*key, httpsign.NewSignConfig(), signerFields)
+	}
+	client := httpsign.NewClient(
+		RequestClient,
+		httpsign.NewClientConfig().SetSigner(signer).SetSignatureName("sig1"),
+	)
+	res, err := client.Do(req)
+	return res, err
+}