Merge pull request proftpd#1293 from proftpd/rewrite-libidn2-issue1286

Issue proftpd#1286: Add support for libidn2, an alternative to libidna, for …

.github/workflows/ci.yml

@@ -73,6 +73,8 @@ jobs:
           yum install -y GeoIP-devel
           # for mod_ldap
           yum install -y openldap-devel cyrus-sasl-devel
+          # for mod_rewrite
+          yum install -y libidn2-devel
           # for memcache support
           yum install -y libmemcached-devel
           # for redis support
@@ -133,6 +135,8 @@ jobs:
           apt-get install -y libldap2-dev libsasl2-dev
           # for mod_ldap runtime support for SCRAM
           apt-get install -y libsasl2-modules-gssapi-mit
+          # for mod_rewrite
+          apt-get install -y libidn2-dev
           # for memcache support
           apt-get install -y libmemcached-dev
           # for redis support

config.h.in

@@ -399,6 +399,9 @@
 /* Define if you have the iconv function.  */
 #undef HAVE_ICONV
 
+/* Define if you have the idn2_to_ascii_8z function.  */
+#undef HAVE_IDN2_TO_ASCII_8Z
+
 /* Define if you have the idna_to_ascii_8z function.  */
 #undef HAVE_IDNA_TO_ASCII_8Z
 
@@ -693,6 +696,9 @@
 /* Define if you have the <iconv.h> header file.  */
 #undef HAVE_ICONV_H
 
+/* Define if you have the <idn2.h> header file.  */
+#undef HAVE_IDN2_H
+
 /* Define if you have the <idna.h> header file.  */
 #undef HAVE_IDNA_H
 

configure

@@ -19758,7 +19758,7 @@ fi
 done
 
 
-for ac_header in netinet/tcp.h arpa/inet.h idna.h libintl.h
+for ac_header in netinet/tcp.h arpa/inet.h idn2.h idna.h libintl.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
 ac_fn_c_check_header_mongrel "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default"
@@ -21285,6 +21285,47 @@ fi
 rm -f core conftest.err conftest.$ac_objext \
     conftest$ac_exeext conftest.$ac_ext
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for idn2_to_ascii_8z" >&5
+$as_echo_n "checking for idn2_to_ascii_8z... " >&6; }
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+    #include <sys/types.h>
+    #ifdef HAVE_IDN2_H
+    #  include <idn2.h>
+    #endif
+
+int
+main ()
+{
+
+    int flags = 0, res = 0;
+    const char *input = NULL;
+    char *output = NULL;
+    res = idn2_to_ascii_8z(input, &output, flags);
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+
+$as_echo "#define HAVE_IDN2_TO_ASCII_8Z 1" >>confdefs.h
+
+    MAIN_LIBS="$MAIN_LIBS -lidn2"
+
+else
+
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+
+
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for idna_to_ascii_8z" >&5
 $as_echo_n "checking for idna_to_ascii_8z... " >&6; }
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext

configure.in

@@ -1715,7 +1715,7 @@ AC_CHECK_HEADERS(netinet/ip.h,,,
     ]
   ])
 
-AC_CHECK_HEADERS(netinet/tcp.h arpa/inet.h idna.h libintl.h)
+AC_CHECK_HEADERS(netinet/tcp.h arpa/inet.h idn2.h idna.h libintl.h)
 AC_CHECK_HEADERS(regex.h sys/stat.h errno.h sys/termios.h sys/termio.h)
 AC_CHECK_HEADERS(sys/statfs.h sys/statvfs.h sys/un.h sys/vfs.h sys/select.h)
 AC_CHECK_HEADERS(termios.h dirent.h ndir.h sys/ndir.h sys/dir.h vmsdir.h)
@@ -1952,6 +1952,30 @@ AC_TRY_LINK(
   ]
 )
 
+AC_MSG_CHECKING([for idn2_to_ascii_8z])
+AC_TRY_COMPILE(
+  [
+    #include <sys/types.h>
+    #ifdef HAVE_IDN2_H
+    #  include <idn2.h>
+    #endif
+  ],
+  [
+    int flags = 0, res = 0;
+    const char *input = NULL;
+    char *output = NULL;
+    res = idn2_to_ascii_8z(input, &output, flags);
+  ],
+  [
+    AC_MSG_RESULT(yes)
+    AC_DEFINE(HAVE_IDN2_TO_ASCII_8Z, 1, [Define if you have idn2_to_ascii_8z])
+    MAIN_LIBS="$MAIN_LIBS -lidn2"
+  ],
+  [
+    AC_MSG_RESULT(no)
+  ]
+)
+
 AC_MSG_CHECKING([for idna_to_ascii_8z])
 AC_TRY_COMPILE(
   [

contrib/mod_rewrite.c

@@ -1,6 +1,6 @@
 /*
  * ProFTPD: mod_rewrite -- a module for rewriting FTP commands
- * Copyright (c) 2001-2020 TJ Saunders
+ * Copyright (c) 2001-2021 TJ Saunders
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -27,11 +27,15 @@
 #include "conf.h"
 #include "privs.h"
 
-#ifdef HAVE_IDNA_H
+#if defined(HAVE_IDNA_H)
 # include <idna.h>
 #endif /* HAVE_IDNA_H */
 
-#define MOD_REWRITE_VERSION		"mod_rewrite/1.0"
+#if defined(HAVE_IDN2_H)
+# include <idn2.h>
+#endif /* HAVE_IDN2_H */
+
+#define MOD_REWRITE_VERSION		"mod_rewrite/1.1"
 
 /* Make sure the version of proftpd is as necessary. */
 #if PROFTPD_VERSION_NUMBER < 0x0001030701
@@ -2034,7 +2038,8 @@ static char *rewrite_map_int_utf8trans(pool *map_pool, char *key) {
   return NULL;
 }
 
-#if defined(HAVE_IDNA_H) && defined(HAVE_IDNA_TO_ASCII_8Z)
+#if (defined(HAVE_IDNA_H) && defined(HAVE_IDNA_TO_ASCII_8Z)) || \
+    (defined(HAVE_IDN2_H) && defined(HAVE_IDN2_TO_ASCII_8Z))
 static char *rewrite_map_int_idnatrans(pool *map_pool, char *key) {
   int flags = 0, res;
   char *ascii_val = NULL, *map_val = NULL;
@@ -2045,6 +2050,16 @@ static char *rewrite_map_int_idnatrans(pool *map_pool, char *key) {
     return NULL;
   }
 
+# if defined(HAVE_IDN2_H) && defined(HAVE_IDN2_TO_ASCII_8Z)
+  flags = IDN2_NFC_INPUT|IDN2_NONTRANSITIONAL;
+  res = idn2_to_ascii_8z(key, &ascii_val, flags);
+  if (res != IDN2_OK) {
+    rewrite_log("rewrite_map_int_idnatrans(): failed transforming IDN2 "
+      "'%s' to ASCII: %s", key, idn2_strerror(res));
+    return NULL;
+  }
+
+# elif defined(HAVE_IDNA_H) && defined(HAVE_IDNA_TO_ASCII_8Z)
   /* TODO: Should we enforce the use of e.g. the IDNA_USE_STD3_ASCII_RULES
    * flag?
    */
@@ -2054,13 +2069,14 @@ static char *rewrite_map_int_idnatrans(pool *map_pool, char *key) {
       "'%s' to ASCII: %s", key, idna_strerror(res));
     return NULL;
   }
+# endif /* IDNA support. */
 
   map_val = pstrdup(map_pool, ascii_val);
   free(ascii_val);
 
   return map_val;
 }
-#endif /* IDNA support */
+#endif /* IDNA or IDN2 support */
 
 /* Rewrite logging functions */
 
@@ -2440,7 +2456,8 @@ MODRET set_rewritemap(cmd_rec *cmd) {
       map = (void *) rewrite_map_int_utf8trans;
 
     } else if (strcmp(mapsrc, "idnatrans") == 0) {
-#if defined(HAVE_IDNA_H) && defined(HAVE_IDNA_TO_ASCII_8Z)
+#if (defined(HAVE_IDNA_H) && defined(HAVE_IDNA_TO_ASCII_8Z)) || \
+    (defined(HAVE_IDN2_H) && defined(HAVE_IDN2_TO_ASCII_8Z))
       map = (void *) rewrite_map_int_idnatrans;
 #else
       CONF_ERROR(cmd, pstrcat(cmd->tmp_pool,