feat: support for url based icons (#840)

Co-authored-by: Elias Schneider <login@eliasschneider.com>

backend/internal/utils/file_util.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"mime"
 	"mime/multipart"
 	"os"
 	"path/filepath"
@@ -57,6 +58,34 @@ func GetImageMimeType(ext string) string {
 	}
 }
 
+func GetImageExtensionFromMimeType(mimeType string) string {
+	// Normalize and strip parameters like `; charset=utf-8`
+	mt := strings.TrimSpace(strings.ToLower(mimeType))
+	if v, _, err := mime.ParseMediaType(mt); err == nil {
+		mt = v
+	}
+	switch mt {
+	case "image/jpeg", "image/jpg":
+		return "jpg"
+	case "image/png":
+		return "png"
+	case "image/svg+xml":
+		return "svg"
+	case "image/x-icon", "image/vnd.microsoft.icon":
+		return "ico"
+	case "image/gif":
+		return "gif"
+	case "image/webp":
+		return "webp"
+	case "image/avif":
+		return "avif"
+	case "image/heic", "image/heif":
+		return "heic"
+	default:
+		return ""
+	}
+}
+
 func CopyEmbeddedFileToDisk(srcFilePath, destFilePath string) error {
 	srcFile, err := resources.FS.Open(srcFilePath)
 	if err != nil {

backend/internal/utils/ip_util.go

@@ -0,0 +1,87 @@
+package utils
+
+import (
+	"net"
+	"strings"
+
+	"github.com/pocket-id/pocket-id/backend/internal/common"
+)
+
+var localIPv6Ranges []*net.IPNet
+
+var localhostIPNets = []*net.IPNet{
+	{IP: net.IPv4(127, 0, 0, 0), Mask: net.CIDRMask(8, 32)}, // 127.0.0.0/8
+	{IP: net.IPv6loopback, Mask: net.CIDRMask(128, 128)},    // ::1/128
+}
+
+var privateLanIPNets = []*net.IPNet{
+	{IP: net.IPv4(10, 0, 0, 0), Mask: net.CIDRMask(8, 32)},     // 10.0.0.0/8
+	{IP: net.IPv4(172, 16, 0, 0), Mask: net.CIDRMask(12, 32)},  // 172.16.0.0/12
+	{IP: net.IPv4(192, 168, 0, 0), Mask: net.CIDRMask(16, 32)}, // 192.168.0.0/16
+}
+
+var tailscaleIPNets = []*net.IPNet{
+	{IP: net.IPv4(100, 64, 0, 0), Mask: net.CIDRMask(10, 32)}, // 100.64.0.0/10
+}
+
+func IsLocalIPv6(ip net.IP) bool {
+	if ip.To4() != nil {
+		return false
+	}
+
+	return listContainsIP(localIPv6Ranges, ip)
+}
+
+func IsLocalhostIP(ip net.IP) bool {
+	return listContainsIP(localhostIPNets, ip)
+}
+
+func IsPrivateLanIP(ip net.IP) bool {
+	if ip.To4() == nil {
+		return false
+	}
+
+	return listContainsIP(privateLanIPNets, ip)
+}
+
+func IsTailscaleIP(ip net.IP) bool {
+	if ip.To4() == nil {
+		return false
+	}
+
+	return listContainsIP(tailscaleIPNets, ip)
+}
+
+func IsPrivateIP(ip net.IP) bool {
+	return IsLocalhostIP(ip) || IsPrivateLanIP(ip) || IsTailscaleIP(ip) || IsLocalIPv6(ip)
+}
+
+func listContainsIP(ipNets []*net.IPNet, ip net.IP) bool {
+	for _, ipNet := range ipNets {
+		if ipNet.Contains(ip) {
+			return true
+		}
+	}
+	return false
+}
+
+func loadLocalIPv6Ranges() {
+	localIPv6Ranges = nil
+	ranges := strings.Split(common.EnvConfig.LocalIPv6Ranges, ",")
+
+	for _, rangeStr := range ranges {
+		rangeStr = strings.TrimSpace(rangeStr)
+		if rangeStr == "" {
+			continue
+		}
+
+		_, ipNet, err := net.ParseCIDR(rangeStr)
+		if err == nil {
+			localIPv6Ranges = append(localIPv6Ranges, ipNet)
+		}
+	}
+}
+
+func init() {
+	loadLocalIPv6Ranges()
+}

backend/internal/utils/ip_util_test.go

@@ -0,0 +1,159 @@
+package utils
+
+import (
+	"net"
+	"testing"
+
+	"github.com/pocket-id/pocket-id/backend/internal/common"
+)
+
+func TestIsLocalhostIP(t *testing.T) {
+	tests := []struct {
+		ip       string
+		expected bool
+	}{
+		{"127.0.0.1", true},
+		{"127.255.255.255", true},
+		{"::1", true},
+		{"192.168.1.1", false},
+	}
+
+	for _, tt := range tests {
+		ip := net.ParseIP(tt.ip)
+		if got := IsLocalhostIP(ip); got != tt.expected {
+			t.Errorf("IsLocalhostIP(%s) = %v, want %v", tt.ip, got, tt.expected)
+		}
+	}
+}
+
+func TestIsPrivateLanIP(t *testing.T) {
+	tests := []struct {
+		ip       string
+		expected bool
+	}{
+		{"10.0.0.1", true},
+		{"172.16.5.4", true},
+		{"192.168.100.200", true},
+		{"8.8.8.8", false},
+		{"::1", false}, // IPv6 should return false
+	}
+
+	for _, tt := range tests {
+		ip := net.ParseIP(tt.ip)
+		if got := IsPrivateLanIP(ip); got != tt.expected {
+			t.Errorf("IsPrivateLanIP(%s) = %v, want %v", tt.ip, got, tt.expected)
+		}
+	}
+}
+
+func TestIsTailscaleIP(t *testing.T) {
+	tests := []struct {
+		ip       string
+		expected bool
+	}{
+		{"100.64.0.1", true},
+		{"100.127.255.254", true},
+		{"8.8.8.8", false},
+		{"::1", false}, // IPv6 should return false
+	}
+
+	for _, tt := range tests {
+		ip := net.ParseIP(tt.ip)
+		if got := IsTailscaleIP(ip); got != tt.expected {
+			t.Errorf("IsTailscaleIP(%s) = %v, want %v", tt.ip, got, tt.expected)
+		}
+	}
+}
+
+func TestIsLocalIPv6(t *testing.T) {
+	// Save and restore env config
+	origRanges := common.EnvConfig.LocalIPv6Ranges
+	defer func() { common.EnvConfig.LocalIPv6Ranges = origRanges }()
+
+	common.EnvConfig.LocalIPv6Ranges = "fd00::/8,fc00::/7"
+	localIPv6Ranges = nil // reset
+	loadLocalIPv6Ranges()
+
+	tests := []struct {
+		ip       string
+		expected bool
+	}{
+		{"fd00::1", true},
+		{"fc00::abcd", true},
+		{"::1", false},         // loopback handled separately
+		{"192.168.1.1", false}, // IPv4 should return false
+	}
+
+	for _, tt := range tests {
+		ip := net.ParseIP(tt.ip)
+		if got := IsLocalIPv6(ip); got != tt.expected {
+			t.Errorf("IsLocalIPv6(%s) = %v, want %v", tt.ip, got, tt.expected)
+		}
+	}
+}
+
+func TestIsPrivateIP(t *testing.T) {
+	// Save and restore env config
+	origRanges := common.EnvConfig.LocalIPv6Ranges
+	defer func() { common.EnvConfig.LocalIPv6Ranges = origRanges }()
+
+	common.EnvConfig.LocalIPv6Ranges = "fd00::/8"
+	localIPv6Ranges = nil // reset
+	loadLocalIPv6Ranges()
+
+	tests := []struct {
+		ip       string
+		expected bool
+	}{
+		{"127.0.0.1", true},             // localhost
+		{"192.168.1.1", true},           // private LAN
+		{"100.64.0.1", true},            // Tailscale
+		{"fd00::1", true},               // local IPv6
+		{"8.8.8.8", false},              // public IPv4
+		{"2001:4860:4860::8888", false}, // public IPv6
+	}
+
+	for _, tt := range tests {
+		ip := net.ParseIP(tt.ip)
+		if got := IsPrivateIP(ip); got != tt.expected {
+			t.Errorf("IsPrivateIP(%s) = %v, want %v", tt.ip, got, tt.expected)
+		}
+	}
+}
+
+func TestListContainsIP(t *testing.T) {
+	_, ipNet1, _ := net.ParseCIDR("10.0.0.0/8")
+	_, ipNet2, _ := net.ParseCIDR("192.168.0.0/16")
+
+	list := []*net.IPNet{ipNet1, ipNet2}
+
+	tests := []struct {
+		ip       string
+		expected bool
+	}{
+		{"10.1.1.1", true},
+		{"192.168.5.5", true},
+		{"172.16.0.1", false},
+	}
+
+	for _, tt := range tests {
+		ip := net.ParseIP(tt.ip)
+		if got := listContainsIP(list, ip); got != tt.expected {
+			t.Errorf("listContainsIP(%s) = %v, want %v", tt.ip, got, tt.expected)
+		}
+	}
+}
+
+func TestInit_LocalIPv6Ranges(t *testing.T) {
+	// Save and restore env config
+	origRanges := common.EnvConfig.LocalIPv6Ranges
+	defer func() { common.EnvConfig.LocalIPv6Ranges = origRanges }()
+
+	common.EnvConfig.LocalIPv6Ranges = "fd00::/8, invalidCIDR ,fc00::/7"
+	localIPv6Ranges = nil
+	loadLocalIPv6Ranges()
+
+	if len(localIPv6Ranges) != 2 {
+		t.Errorf("expected 2 valid IPv6 ranges, got %d", len(localIPv6Ranges))
+	}
+}