From f05f58c30cacb5f1114e619f9ea6088ebaa90b96 Mon Sep 17 00:00:00 2001
From: Hiroyuki <weeb_hiroyuki@outlook.com>
Date: Thu, 25 Mar 2021 22:12:07 -0400
Subject: [PATCH] Add support for the bit sizes of the public keys

---
 routes/get.go | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/routes/get.go b/routes/get.go
index 47564c1..0c0bbce 100644
--- a/routes/get.go
+++ b/routes/get.go
@@ -1,6 +1,9 @@
 package routes
 
 import (
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/rsa"
 	"crypto/sha1"
 	"crypto/tls"
 	"crypto/x509"
@@ -125,6 +128,25 @@ func GetCertificateInformationEncoded(c *gin.Context) {
 
 	sum := sha1.Sum(certificate.Raw)
 
+	var bitLength int
+
+	switch certificate.PublicKeyAlgorithm {
+	case x509.RSA:
+		if rsaKey, ok := certificate.PublicKey.(*rsa.PublicKey); ok {
+			bitLength = rsaKey.N.BitLen()
+		} else {
+			panic("expected rsa.PublicKey for type x509.RSA")
+		}
+	case x509.ECDSA:
+		if ecdsaKey, ok := certificate.PublicKey.(*ecdsa.PublicKey); ok {
+			bitLength = ecdsaKey.Params().BitSize
+		} else {
+			panic("expected ecdsa.PublicKey for type x509.ECDSA")
+		}
+	case x509.Ed25519:
+		bitLength = ed25519.PublicKeySize
+	}
+
 	c.JSON(http.StatusOK, gin.H{
 		"status": true,
 		"subject": gin.H{
@@ -153,6 +175,7 @@ func GetCertificateInformationEncoded(c *gin.Context) {
 		"extendedKeyUsageAsText": extendedKeyUsagesText,
 		"san":                    certificate.DNSNames,
 		"fingerprint":            hex.EncodeToString(sum[:]),
+		"bitLength":              bitLength,
 	})
 }
 
@@ -271,6 +294,23 @@ func GetCertificateInfo(c *gin.Context) {
 
 	sum := sha1.Sum(certificate.Raw)
 
+	var bitLength int
+
+	switch certificate.PublicKeyAlgorithm {
+	case x509.RSA:
+		if rsaKey, ok := certificate.PublicKey.(*rsa.PublicKey); ok {
+			bitLength = rsaKey.N.BitLen()
+		} else {
+			panic("expected rsa.PublicKey for type x509.RSA")
+		}
+	case x509.ECDSA:
+		if ecdsaKey, ok := certificate.PublicKey.(*ecdsa.PublicKey); ok {
+			bitLength = ecdsaKey.Params().BitSize
+		} else {
+			panic("expected ecdsa.PublicKey for type x509.ECDSA")
+		}
+	}
+
 	c.JSON(http.StatusOK, gin.H{
 		"status": true,
 		"subject": gin.H{
@@ -306,6 +346,7 @@ func GetCertificateInfo(c *gin.Context) {
 		"extendedKeyUsageAsText": extendedKeyUsagesText,
 		"san":                    certificate.DNSNames,
 		"fingerprint":            hex.EncodeToString(sum[:]),
+		"bitLength":              bitLength,
 		"connection": gin.H{
 			"tlsVersion":  tlsVersion,
 			"cipherSuite": cipherSuite,