Add SPDX license identifiers to source files under the LGPL

[thirdparty/systemd.git] / src / shared / dns-domain.c

diff --git a/src/shared/dns-domain.c b/src/shared/dns-domain.c
index 892f0aadf586a89a7439e37313b81007b465a74f..670aa48800104faea3689f2285e05468b3bcb1e7 100644 (file)
--- a/src/shared/dns-domain.c
+++ b/src/shared/dns-domain.c
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
 /***
   This file is part of systemd.
 
@@ -17,9 +18,11 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  ***/
 
-#ifdef HAVE_LIBIDN
-#include <idna.h>
-#include <stringprep.h>
+#if HAVE_LIBIDN2
+#  include <idn2.h>
+#elif HAVE_LIBIDN
+#  include <idna.h>
+#  include <stringprep.h>
 #endif
 
 #include <endian.h>
@@ -74,7 +77,7 @@ int dns_label_unescape(const char **name, char *dest, size_t sz) {
                                 /* Ending NUL */
                                 return -EINVAL;
 
-                        else if (*n == '\\' || *n == '.') {
+                        else if (IN_SET(*n, '\\', '.')) {
                                 /* Escaped backslash or dot */
 
                                 if (d)
@@ -162,7 +165,7 @@ int dns_label_unescape_suffix(const char *name, const char **label_terminal, cha
         }
 
         terminal = *label_terminal;
-        assert(*terminal == '.' || *terminal == 0);
+        assert(IN_SET(*terminal, 0, '.'));
 
         /* Skip current terminal character (and accept domain names ending it ".") */
         if (*terminal == 0)
@@ -226,7 +229,7 @@ int dns_label_escape(const char *p, size_t l, char *dest, size_t sz) {
         q = dest;
         while (l > 0) {
 
-                if (*p == '.' || *p == '\\') {
+                if (IN_SET(*p, '.', '\\')) {
 
                         /* Dot or backslash */
 
@@ -238,8 +241,7 @@ int dns_label_escape(const char *p, size_t l, char *dest, size_t sz) {
 
                         sz -= 2;
 
-                } else if (*p == '_' ||
-                           *p == '-' ||
+                } else if (IN_SET(*p, '_', '-') ||
                            (*p >= '0' && *p <= '9') ||
                            (*p >= 'a' && *p <= 'z') ||
                            (*p >= 'A' && *p <= 'Z')) {
@@ -299,8 +301,8 @@ int dns_label_escape_new(const char *p, size_t l, char **ret) {
         return r;
 }
 
+#if HAVE_LIBIDN
 int dns_label_apply_idna(const char *encoded, size_t encoded_size, char *decoded, size_t decoded_max) {
-#ifdef HAVE_LIBIDN
         _cleanup_free_ uint32_t *input = NULL;
         size_t input_size, l;
         const char *p;
@@ -348,13 +350,9 @@ int dns_label_apply_idna(const char *encoded, size_t encoded_size, char *decoded
                 decoded[l] = 0;
 
         return (int) l;
-#else
-        return 0;
-#endif
 }
 
 int dns_label_undo_idna(const char *encoded, size_t encoded_size, char *decoded, size_t decoded_max) {
-#ifdef HAVE_LIBIDN
         size_t input_size, output_size;
         _cleanup_free_ uint32_t *input = NULL;
         _cleanup_free_ char *result = NULL;
@@ -399,10 +397,8 @@ int dns_label_undo_idna(const char *encoded, size_t encoded_size, char *decoded,
                 decoded[w] = 0;
 
         return w;
-#else
-        return 0;
-#endif
 }
+#endif
 
 int dns_name_concat(const char *a, const char *b, char **_ret) {
         _cleanup_free_ char *ret = NULL;
@@ -1076,7 +1072,7 @@ int dns_service_split(const char *joined, char **_name, char **_type, char **_do
                                 if (!name)
                                         return -ENOMEM;
 
-                                type = strjoin(b, ".", c, NULL);
+                                type = strjoin(b, ".", c);
                                 if (!type)
                                         return -ENOMEM;
 
@@ -1090,7 +1086,7 @@ int dns_service_split(const char *joined, char **_name, char **_type, char **_do
 
                         name = NULL;
 
-                        type = strjoin(a, ".", b, NULL);
+                        type = strjoin(a, ".", b);
                         if (!type)
                                 return -ENOMEM;
 
@@ -1274,6 +1270,49 @@ int dns_name_common_suffix(const char *a, const char *b, const char **ret) {
 }
 
 int dns_name_apply_idna(const char *name, char **ret) {
+        /* Return negative on error, 0 if not implemented, positive on success. */
+
+#if HAVE_LIBIDN2
+        int r;
+        _cleanup_free_ char *t = NULL;
+
+        assert(name);
+        assert(ret);
+
+        r = idn2_lookup_u8((uint8_t*) name, (uint8_t**) &t,
+                           IDN2_NFC_INPUT | IDN2_NONTRANSITIONAL);
+        log_debug("idn2_lookup_u8: %s → %s", name, t);
+        if (r == IDN2_OK) {
+                if (!startswith(name, "xn--")) {
+                        _cleanup_free_ char *s = NULL;
+
+                        r = idn2_to_unicode_8z8z(t, &s, 0);
+                        if (r != IDN2_OK) {
+                                log_debug("idn2_to_unicode_8z8z(\"%s\") failed: %d/%s",
+                                          t, r, idn2_strerror(r));
+                                return 0;
+                        }
+
+                        if (!streq_ptr(name, s)) {
+                                log_debug("idn2 roundtrip failed: \"%s\" → \"%s\" → \"%s\", ignoring.",
+                                          name, t, s);
+                                return 0;
+                        }
+                }
+
+                *ret = t;
+                t = NULL;
+                return 1; /* *ret has been written */
+        }
+
+        log_debug("idn2_lookup_u8(\"%s\") failed: %d/%s", name, r, idn2_strerror(r));
+        if (r == IDN2_2HYPHEN)
+                /* The name has two hypens — forbidden by IDNA2008 in some cases */
+                return 0;
+        if (IN_SET(r, IDN2_TOO_BIG_DOMAIN, IDN2_TOO_BIG_LABEL))
+                return -ENOSPC;
+        return -EINVAL;
+#elif HAVE_LIBIDN
         _cleanup_free_ char *buf = NULL;
         size_t n = 0, allocated = 0;
         bool first = true;
@@ -1309,7 +1348,7 @@ int dns_name_apply_idna(const char *name, char **ret) {
                 else
                         buf[n++] = '.';
 
-                n +=r;
+                n += r;
         }
 
         if (n > DNS_HOSTNAME_MAX)
@@ -1322,5 +1361,20 @@ int dns_name_apply_idna(const char *name, char **ret) {
         *ret = buf;
         buf = NULL;
 
-        return (int) n;
+        return 1;
+#else
+        return 0;
+#endif
+}
+
+int dns_name_is_valid_or_address(const char *name) {
+        /* Returns > 0 if the specified name is either a valid IP address formatted as string or a valid DNS name */
+
+        if (isempty(name))
+                return 0;
+
+        if (in_addr_from_string_auto(name, NULL, NULL) >= 0)
+                return 1;
+
+        return dns_name_is_valid(name);
 }