Certificate signing request generator modules in rust and golang

Cargo.toml

@@ -0,0 +1,7 @@
+[workspace]
+
+members = [
+    "samples/csr-rust",
+    "samples/dns-rust",
+    "samples/hello-world-rust"
+]

Makefile

@@ -16,6 +16,9 @@ build-opa-policy-wasm:
 build-ebpf-xdp-prog:
 	cd samples/ebpf; make
 
+build-csr-gen-rust-wasm:
+	cd samples/csr-rust; make
+
 load-hello-world-rust-wasm:
 	sudo ./w3k load -file samples/hello-world-rust/target/wasm32-unknown-unknown/release/hello-world.wasm
 

samples/csr-go/Makefile

@@ -0,0 +1,5 @@
+go-csr:
+	tinygo build -o csr-go.wasm \
+	-target=wasm \
+	-gc=leaking -panic=trap -scheduler=none \
+	-opt=z main.go

samples/csr-go/main.go

@@ -0,0 +1,57 @@
+package main
+
+import (
+	"crypto/rand"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"encoding/pem"
+	"unsafe"
+)
+
+//export _debug
+func _debug(m string) int32
+
+//export gen_csr
+func gen_csr(privPtr *uint32, privLen int) uint32 {
+
+	unsafePtr := unsafe.Pointer(privPtr)
+
+	priv := *(*[]byte)(unsafe.Pointer(&struct {
+		addr uintptr
+		len  int
+		cap  int
+	}{uintptr(unsafePtr), privLen, privLen}))
+
+	block, _ := pem.Decode(priv)
+
+	rsaPriv, err := x509.ParsePKCS1PrivateKey(block.Bytes)
+	if err != nil {
+		_debug("failed to parse priv key" + err.Error())
+	}
+
+	var csrTemplate = x509.CertificateRequest{
+		Subject:            pkix.Name{},
+		SignatureAlgorithm: x509.SHA256WithRSA,
+		ExtraExtensions: []pkix.Extension{
+			{
+				Id:       asn1.ObjectIdentifier{2, 5, 29, 19},
+				Critical: true,
+			},
+		},
+	}
+	csrCertificate, err := x509.CreateCertificateRequest(rand.Reader, &csrTemplate, rsaPriv)
+	if err != nil {
+		_debug("failed to create certificate signing request" + err.Error())
+	}
+	csr := pem.EncodeToMemory(&pem.Block{
+		Type: "CERTIFICATE REQUEST", Bytes: csrCertificate,
+	})
+
+	csrPtr := uint16(uintptr(unsafe.Pointer(&csr[0])))
+	csrLen := uint16(len(csr))
+
+	return (uint32(csrPtr) << uint32(16)) | uint32(csrLen)
+}
+
+func main() {}

samples/csr-rust/.cargo/config.toml

@@ -0,0 +1,3 @@
+[build]
+# rustflags = ["-C", "target-feature=+multivalue"]
+target = "wasm32-unknown-unknown"