Link GetAdaptersAddresses, rather than loading it on-demand.

This function has been present since Windows XP.

changes/iphplapi

+  o Removed features:
+   - Tor no longer attempts to run on Windows environments without the
+     GetAdaptersAddresses() function. This function has existed since
+     Windows XP, which is itself already older than we support.

src/lib/net/address.c

@@ -1479,17 +1479,7 @@ ip_adapter_addresses_to_smartlist(const IP_ADAPTER_ADDRESSES *addresses)
 STATIC smartlist_t *
 get_interface_addresses_win32(int severity, sa_family_t family)
 {
-  /*
-    XXXX We can assume that this function exists now; we can't
-    XXXX provide backward compatibility to pre-windows-XP.
-  */
-  /* Windows XP began to provide GetAdaptersAddresses. Windows 2000 had a
-     "GetAdaptersInfo", but that's deprecated; let's just try
-     GetAdaptersAddresses and fall back to connect+getsockname.
-  */
-  HANDLE lib = load_windows_system_library(TEXT("iphlpapi.dll"));
   smartlist_t *result = NULL;
-  GetAdaptersAddresses_fn_t fn;
   ULONG size, res;
   IP_ADAPTER_ADDRESSES *addresses = NULL;
 
@@ -1499,27 +1489,16 @@ get_interface_addresses_win32(int severity, sa_family_t family)
                GAA_FLAG_SKIP_MULTICAST | \
                GAA_FLAG_SKIP_DNS_SERVER)
 
-  if (!lib) {
-    log_fn(severity, LD_NET, "Unable to load iphlpapi.dll");
-    goto done;
-  }
-
-  if (!(fn = (GetAdaptersAddresses_fn_t)
-                  GetProcAddress(lib, "GetAdaptersAddresses"))) {
-    log_fn(severity, LD_NET, "Unable to obtain pointer to "
-           "GetAdaptersAddresses");
-    goto done;
-  }
-
   /* Guess how much space we need. */
   size = 15*1024;
   addresses = tor_malloc(size);
-  res = fn(family, FLAGS, NULL, addresses, &size);
+  /* Exists in windows XP and later. */
+  res = GetAdaptersAddresses(family, FLAGS, NULL, addresses, &size);
   if (res == ERROR_BUFFER_OVERFLOW) {
     /* we didn't guess that we needed enough space; try again */
     tor_free(addresses);
     addresses = tor_malloc(size);
-    res = fn(AF_UNSPEC, FLAGS, NULL, addresses, &size);
+    res = GetAdaptersAddresses(AF_UNSPEC, FLAGS, NULL, addresses, &size);
   }
   if (res != NO_ERROR) {
     log_fn(severity, LD_NET, "GetAdaptersAddresses failed (result: %lu)", res);
@@ -1529,8 +1508,6 @@ get_interface_addresses_win32(int severity, sa_family_t family)
   result = ip_adapter_addresses_to_smartlist(addresses);
 
  done:
-  if (lib)
-    FreeLibrary(lib);
   tor_free(addresses);
   return result;
 }

src/or/include.am

@@ -162,7 +162,7 @@ src_or_tor_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ @TOR_LDFLAGS_libev
 src_or_tor_LDADD = $(TOR_INTERNAL_LIBS) \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ @TOR_OPENSSL_LIBS@ \
-	@TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
+	@TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
 	@CURVE25519_LIBS@ @TOR_SYSTEMD_LIBS@ \
 	@TOR_LZMA_LIBS@ @TOR_ZSTD_LIBS@
 
@@ -173,7 +173,8 @@ src_or_tor_cov_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
 src_or_tor_cov_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ @TOR_LDFLAGS_libevent@
 src_or_tor_cov_LDADD = $(TOR_INTERNAL_TESTING_LIBS) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ @TOR_OPENSSL_LIBS@ \
-	@TOR_LIB_WS32@ @TOR_LIB_GDI@ @CURVE25519_LIBS@ @TOR_SYSTEMD_LIBS@ \
+	@TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ \
+        @CURVE25519_LIBS@ @TOR_SYSTEMD_LIBS@ \
 	@TOR_LZMA_LIBS@ @TOR_ZSTD_LIBS@
 endif
 

src/test/fuzz/include.am

@@ -11,7 +11,7 @@ FUZZING_LIBS = \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ \
 	@TOR_LIBEVENT_LIBS@ @TOR_OPENSSL_LIBS@ \
-	@TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ @CURVE25519_LIBS@ \
+	@TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ @CURVE25519_LIBS@ \
 	@TOR_SYSTEMD_LIBS@ \
 	@TOR_LZMA_LIBS@ \
 	@TOR_ZSTD_LIBS@

src/test/include.am

@@ -221,7 +221,7 @@ src_test_test_switch_id_LDADD = \
 	$(TOR_UTIL_TESTING_LIBS) \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ \
-	@TOR_LIB_WS32@ @TOR_LIB_USERENV@ \
+	@TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_USERENV@ \
 	@TOR_LZMA_LIBS@ @TOR_ZSTD_LIBS@
 
 src_test_test_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ \
@@ -230,7 +230,7 @@ src_test_test_LDADD = \
         $(TOR_INTERNAL_TESTING_LIBS) \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ \
-	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
+	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
 	@CURVE25519_LIBS@ \
 	@TOR_SYSTEMD_LIBS@ @TOR_LZMA_LIBS@ @TOR_ZSTD_LIBS@
 
@@ -253,7 +253,7 @@ src_test_bench_LDADD = \
         $(TOR_INTERNAL_LIBS) \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ \
-	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
+	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
 	@CURVE25519_LIBS@ \
 	@TOR_SYSTEMD_LIBS@ @TOR_LZMA_LIBS@ @TOR_ZSTD_LIBS@
 
@@ -263,7 +263,7 @@ src_test_test_workqueue_LDADD = \
         $(TOR_INTERNAL_TESTING_LIBS) \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ \
-	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
+	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
 	@CURVE25519_LIBS@ \
 	@TOR_LZMA_LIBS@ @TOR_ZSTD_LIBS@
 
@@ -275,7 +275,7 @@ src_test_test_timers_LDADD = \
 	$(TOR_UTIL_TESTING_LIBS) \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ \
-	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
+	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
 	@CURVE25519_LIBS@ \
 	@TOR_LZMA_LIBS@
 src_test_test_timers_LDFLAGS = $(src_test_test_LDFLAGS)
@@ -305,7 +305,7 @@ src_test_test_ntor_cl_LDADD = \
         $(TOR_INTERNAL_LIBS) \
 	$(rust_ldadd) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ \
-	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
+	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ \
 	@CURVE25519_LIBS@ @TOR_LZMA_LIBS@
 src_test_test_ntor_cl_AM_CPPFLAGS =	       \
 	$(AM_CPPFLAGS)
@@ -315,7 +315,7 @@ src_test_test_hs_ntor_cl_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@
 src_test_test_hs_ntor_cl_LDADD = \
 	$(TOR_INTERNAL_LIBS) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ \
-	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_GDI@ @CURVE25519_LIBS@
+	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @CURVE25519_LIBS@
 src_test_test_hs_ntor_cl_AM_CPPFLAGS =	       \
 	$(AM_CPPFLAGS)
 
@@ -326,7 +326,7 @@ src_test_test_bt_cl_LDADD = \
 	$(TOR_UTIL_TESTING_LIBS) \
 	$(rust_ldadd) \
 	@TOR_LIB_MATH@ \
-	@TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@
+	@TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@
 src_test_test_bt_cl_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
 src_test_test_bt_cl_CPPFLAGS= $(src_test_AM_CPPFLAGS) $(TEST_CPPFLAGS)
 

src/tools/include.am

@@ -9,7 +9,7 @@ src_tools_tor_resolve_LDFLAGS =
 src_tools_tor_resolve_LDADD = \
         $(TOR_UTIL_LIBS) \
 	$(rust_ldadd) \
-	@TOR_LIB_MATH@ @TOR_LIB_WS32@ @TOR_LIB_USERENV@
+	@TOR_LIB_MATH@ @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_USERENV@
 
 if COVERAGE_ENABLED
 src_tools_tor_cov_resolve_SOURCES = src/tools/tor-resolve.c
@@ -27,7 +27,7 @@ src_tools_tor_gencert_LDADD = \
         $(TOR_UTIL_LIBS) \
 	$(rust_ldadd) \
 	@TOR_LIB_MATH@ @TOR_ZLIB_LIBS@ @TOR_OPENSSL_LIBS@ \
-	@TOR_LIB_WS32@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ @CURVE25519_LIBS@
+	@TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @TOR_LIB_USERENV@ @CURVE25519_LIBS@
 
 if COVERAGE_ENABLED
 src_tools_tor_cov_gencert_SOURCES = src/tools/tor-gencert.c
@@ -38,7 +38,7 @@ src_tools_tor_cov_gencert_LDADD = \
     $(TOR_CRYPTO_TESTING_LIBS) \
     $(TOR_UTIL_TESTING_LIBS) \
     @TOR_LIB_MATH@ @TOR_ZLIB_LIBS@ @TOR_OPENSSL_LIBS@ \
-    @TOR_LIB_WS32@ @TOR_LIB_GDI@ @CURVE25519_LIBS@
+    @TOR_LIB_WS32@ @TOR_LIB_IPHLPAPI@ @TOR_LIB_GDI@ @CURVE25519_LIBS@
 endif
 
 if BUILD_LIBTORRUNNER