feat: add ldap component (#3568)

* add ldap component

* fix: fix russian comments, tls cert verify default true

* feat: remove replaces go mod for local dev

1 files changed, 144 insertions, 0 deletions

diff --git a/util/ldap/ldap.go b/util/ldap/ldap.go
new file mode 100644
index 00000000..1c7a20e7
--- /dev/null
+++ b/util/ldap/ldap.go
@@ -0,0 +1,144 @@
+package ldaputil
+
+import (
+    "crypto/tls"
+    "fmt"
+
+    "github.com/go-ldap/ldap/v3"
+)
+
+type Config struct {
+    Host        string
+    Port        int
+    UseTLS      bool
+    BindDN      string
+    Password    string
+    BaseDN      string
+    UserFilter  string
+    UserAttr    string
+    FlagField   string
+    TruthyVals  []string
+    Invert      bool
+}
+
+// FetchVlessFlags returns map[email]enabled
+func FetchVlessFlags(cfg Config) (map[string]bool, error) {
+    addr := fmt.Sprintf("%s:%d", cfg.Host, cfg.Port)
+    var conn *ldap.Conn
+    var err error
+    if cfg.UseTLS {
+        conn, err = ldap.DialTLS("tcp", addr, &tls.Config{InsecureSkipVerify: false})
+    } else {
+        conn, err = ldap.Dial("tcp", addr)
+    }
+    if err != nil {
+        return nil, err
+    }
+    defer conn.Close()
+
+    if cfg.BindDN != "" {
+        if err := conn.Bind(cfg.BindDN, cfg.Password); err != nil {
+            return nil, err
+        }
+    }
+
+    if cfg.UserFilter == "" {
+        cfg.UserFilter = "(objectClass=person)"
+    }
+    if cfg.UserAttr == "" {
+        cfg.UserAttr = "mail"
+    }
+    // if field not set we fallback to legacy vless_enabled
+    if cfg.FlagField == "" {
+        cfg.FlagField = "vless_enabled"
+    }
+
+    req := ldap.NewSearchRequest(
+        cfg.BaseDN,
+        ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false,
+        cfg.UserFilter,
+        []string{cfg.UserAttr, cfg.FlagField},
+        nil,
+    )
+
+    res, err := conn.Search(req)
+    if err != nil {
+        return nil, err
+    }
+
+    result := make(map[string]bool, len(res.Entries))
+    for _, e := range res.Entries {
+        user := e.GetAttributeValue(cfg.UserAttr)
+        if user == "" {
+            continue
+        }
+        val := e.GetAttributeValue(cfg.FlagField)
+        enabled := false
+        for _, t := range cfg.TruthyVals {
+            if val == t {
+                enabled = true
+                break
+            }
+        }
+        if cfg.Invert {
+            enabled = !enabled
+        }
+        result[user] = enabled
+    }
+    return result, nil
+}
+
+// AuthenticateUser searches user by cfg.UserAttr and attempts to bind with provided password.
+func AuthenticateUser(cfg Config, username, password string) (bool, error) {
+    addr := fmt.Sprintf("%s:%d", cfg.Host, cfg.Port)
+    var conn *ldap.Conn
+    var err error
+    if cfg.UseTLS {
+        conn, err = ldap.DialTLS("tcp", addr, &tls.Config{InsecureSkipVerify: false})
+    } else {
+        conn, err = ldap.Dial("tcp", addr)
+    }
+    if err != nil {
+        return false, err
+    }
+    defer conn.Close()
+
+    // Optional initial bind for search
+    if cfg.BindDN != "" {
+        if err := conn.Bind(cfg.BindDN, cfg.Password); err != nil {
+            return false, err
+        }
+    }
+
+    if cfg.UserFilter == "" {
+        cfg.UserFilter = "(objectClass=person)"
+    }
+    if cfg.UserAttr == "" {
+        cfg.UserAttr = "uid"
+    }
+
+    // Build filter to find specific user
+    filter := fmt.Sprintf("(&%s(%s=%s))", cfg.UserFilter, cfg.UserAttr, ldap.EscapeFilter(username))
+    req := ldap.NewSearchRequest(
+        cfg.BaseDN,
+        ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 1, 0, false,
+        filter,
+        []string{"dn"},
+        nil,
+    )
+    res, err := conn.Search(req)
+    if err != nil {
+        return false, err
+    }
+    if len(res.Entries) == 0 {
+        return false, nil
+    }
+    userDN := res.Entries[0].DN
+    // Try to bind as the user
+    if err := conn.Bind(userDN, password); err != nil {
+        return false, nil
+    }
+    return true, nil
+}
+
+