Files
Charon/backend/internal/utils/url.go
2026-01-26 19:22:05 +00:00

134 lines
3.5 KiB
Go

package utils
import (
"errors"
"net/url"
"strings"
"github.com/gin-gonic/gin"
"gorm.io/gorm"
"github.com/Wikid82/charon/backend/internal/models"
)
// GetConfiguredPublicURL returns the configured, normalized public URL.
//
// Security note:
// This function intentionally never derives URLs from request data (Host/X-Forwarded-*),
// so it is safe to use for embedding external links (e.g., invite emails).
func GetConfiguredPublicURL(db *gorm.DB) (string, bool) {
var setting models.Setting
if err := db.Where("key = ?", "app.public_url").First(&setting).Error; err != nil {
return "", false
}
normalized, err := normalizeConfiguredPublicURL(setting.Value)
if err != nil {
return "", false
}
return normalized, true
}
// GetPublicURL retrieves the configured public URL or falls back to request host.
// This should be used for all user-facing URLs (emails, invite links).
func GetPublicURL(db *gorm.DB, c *gin.Context) string {
var setting models.Setting
if err := db.Where("key = ?", "app.public_url").First(&setting).Error; err == nil {
if setting.Value != "" {
return strings.TrimSuffix(setting.Value, "/")
}
}
// Fallback to request-derived URL
return getBaseURL(c)
}
func normalizeConfiguredPublicURL(raw string) (string, error) {
raw = strings.TrimSpace(raw)
if raw == "" {
return "", errors.New("public URL is empty")
}
if strings.ContainsAny(raw, "\r\n") {
return "", errors.New("public URL contains invalid characters")
}
parsed, err := url.Parse(raw)
if err != nil {
return "", err
}
if parsed.Scheme != "http" && parsed.Scheme != "https" {
return "", errors.New("public URL must use http or https")
}
if parsed.Host == "" {
return "", errors.New("public URL must include a host")
}
if parsed.User != nil {
return "", errors.New("public URL must not include userinfo")
}
if parsed.RawQuery != "" || parsed.Fragment != "" {
return "", errors.New("public URL must not include query or fragment")
}
if parsed.Path != "" && parsed.Path != "/" {
return "", errors.New("public URL must not include a path")
}
if parsed.Opaque != "" {
return "", errors.New("public URL must not be opaque")
}
normalized := (&url.URL{Scheme: parsed.Scheme, Host: parsed.Host}).String()
return normalized, nil
}
// getBaseURL extracts the base URL from the request.
func getBaseURL(c *gin.Context) string {
scheme := "https"
if c.Request.TLS == nil {
// Check for X-Forwarded-Proto header
if proto := c.GetHeader("X-Forwarded-Proto"); proto != "" {
scheme = proto
} else {
scheme = "http"
}
}
return scheme + "://" + c.Request.Host
}
// ValidateURL validates that a URL is properly formatted for use as an application URL.
// Returns error message if invalid, empty string if valid.
func ValidateURL(rawURL string) (normalized, warning string, err error) {
// Parse URL
parsed, parseErr := url.Parse(rawURL)
if parseErr != nil {
return "", "", parseErr
}
// Validate scheme
if parsed.Scheme != "http" && parsed.Scheme != "https" {
return "", "", &url.Error{
Op: "parse",
URL: rawURL,
Err: nil,
}
}
// Warn if HTTP
if parsed.Scheme == "http" {
warning = "Using HTTP is not recommended. Consider using HTTPS for security."
}
// Reject URLs with path components beyond "/"
if parsed.Path != "" && parsed.Path != "/" {
return "", "", &url.Error{
Op: "validate",
URL: rawURL,
Err: nil,
}
}
// Normalize URL (remove trailing slash, keep scheme and host)
normalized = strings.TrimSuffix(rawURL, "/")
return normalized, warning, nil
}