cleanup - read_config() and ipv4_local_prefixlen

Test:
  git grep 'read_config|ipv4_local_prefixlen|default_pdp_interface'
  comes up empty

Bug: 144730808
Test: atest clatd_test netd_integration_test
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Original-Change: https://android-review.googlesource.com/1322226
Merged-In: I67b70fe298f69ac51dfbc5daf4078b842fb62808
Change-Id: I67b70fe298f69ac51dfbc5daf4078b842fb62808

5 files changed, 5 insertions, 48 deletions

diff --git a/clatd.c b/clatd.c
index 50693f5..edae761 100644
--- a/clatd.c
+++ b/clatd.c
@@ -98,7 +98,7 @@ int configure_packet_socket(int sock) {
   struct sockaddr_ll sll = {
     .sll_family   = AF_PACKET,
     .sll_protocol = htons(ETH_P_IPV6),
-    .sll_ifindex  = if_nametoindex(Global_Clatd_Config.default_pdp_interface),
+    .sll_ifindex  = if_nametoindex(Global_Clatd_Config.native_ipv6_interface),
     .sll_pkttype  = PACKET_OTHERHOST,  // The 464xlat IPv6 address is not assigned to the kernel.
   };
   if (bind(sock, (struct sockaddr *)&sll, sizeof(sll))) {
@@ -318,11 +318,7 @@ int detect_mtu(const struct in6_addr *plat_subnet, uint32_t plat_suffix, uint32_
  */
 void configure_interface(const char *uplink_interface, const char *plat_prefix, const char *v4_addr,
                          const char *v6_addr, struct tun_data *tunnel, uint32_t mark) {
-  if (!read_config("/system/etc/clatd.conf", uplink_interface)) {
-    logmsg(ANDROID_LOG_FATAL, "read_config failed");
-    exit(1);
-  }
-
+  Global_Clatd_Config.native_ipv6_interface = uplink_interface;
   if (!plat_prefix || inet_pton(AF_INET6, plat_prefix, &Global_Clatd_Config.plat_subnet) <= 0) {
     logmsg(ANDROID_LOG_FATAL, "invalid IPv6 address specified for plat prefix: %s", plat_prefix);
     exit(1);
@@ -430,7 +426,7 @@ void event_loop(struct tun_data *tunnel) {
 
     time_t now = time(NULL);
     if (last_interface_poll < (now - INTERFACE_POLL_FREQUENCY)) {
-      if (ipv6_address_changed(Global_Clatd_Config.default_pdp_interface)) {
+      if (ipv6_address_changed(Global_Clatd_Config.native_ipv6_interface)) {
         break;
       }
     }
diff --git a/clatd.conf b/clatd.conf
index 36fcafd..e69de29 100644
--- a/clatd.conf
+++ b/clatd.conf
@@ -1 +0,0 @@
-temporary_placeholder 0
diff --git a/clatd_test.cpp b/clatd_test.cpp
index e24b036..514aaa8 100644
--- a/clatd_test.cpp
+++ b/clatd_test.cpp
@@ -585,7 +585,7 @@ class ClatdTest : public ::testing::Test {
     inet_pton(AF_INET, kIPv4LocalAddr, &Global_Clatd_Config.ipv4_local_subnet);
     inet_pton(AF_INET6, kIPv6PlatSubnet, &Global_Clatd_Config.plat_subnet);
     memset(&Global_Clatd_Config.ipv6_local_subnet, 0, sizeof(in6_addr));
-    Global_Clatd_Config.default_pdp_interface = const_cast<char *>(sTun.name().c_str());
+    Global_Clatd_Config.native_ipv6_interface = const_cast<char *>(sTun.name().c_str());
   }
 
   // Static because setting up the tun interface takes about 40ms.
@@ -631,8 +631,6 @@ TEST_F(ClatdTest, DetectMtu) {
 }
 
 TEST_F(ClatdTest, ConfigureTunIpManual) {
-  Global_Clatd_Config.ipv4_local_prefixlen = 29;
-
   // Create an interface for configure_tun_ip to configure and bring up.
   TunInterface v4Iface;
   ASSERT_EQ(0, v4Iface.init());
diff --git a/config.c b/config.c
index f7c9724..d83b958 100644
--- a/config.c
+++ b/config.c
@@ -42,37 +42,3 @@ struct clat_config Global_Clatd_Config;
  *   returns: 0 if the subnets are different, 1 if they are the same.
  */
 int ipv6_prefix_equal(struct in6_addr *a1, struct in6_addr *a2) { return !memcmp(a1, a2, 8); }
-
-/* function: read_config
- * reads the config file and parses it into the global variable Global_Clatd_Config. returns 0 on
- * failure, 1 on success
- *   file             - filename to parse
- *   uplink_interface - interface to use to reach the internet and supplier of address space
- */
-int read_config(const char *file, const char *uplink_interface) {
-  cnode *root   = config_node("", "");
-
-  if (!root) {
-    logmsg(ANDROID_LOG_FATAL, "out of memory");
-    return 0;
-  }
-
-  memset(&Global_Clatd_Config, '\0', sizeof(Global_Clatd_Config));
-
-  config_load_file(root, file);
-  if (root->first_child == NULL) {
-    logmsg(ANDROID_LOG_FATAL, "Could not read config file %s", file);
-    goto failed;
-  }
-
-  Global_Clatd_Config.default_pdp_interface = strdup(uplink_interface);
-  if (!Global_Clatd_Config.default_pdp_interface) goto failed;
-
-  Global_Clatd_Config.ipv4_local_prefixlen = 29;
-
-  return 1;
-
-failed:
-  free(root);
-  return 0;
-}
diff --git a/config.h b/config.h
index 32558ca..0152df0 100644
--- a/config.h
+++ b/config.h
@@ -24,14 +24,12 @@
 struct clat_config {
   struct in6_addr ipv6_local_subnet;
   struct in_addr ipv4_local_subnet;
-  int16_t ipv4_local_prefixlen;
   struct in6_addr plat_subnet;
-  char *default_pdp_interface;
+  const char *native_ipv6_interface;
 };
 
 extern struct clat_config Global_Clatd_Config;
 
-int read_config(const char *file, const char *uplink_interface);
 int ipv6_prefix_equal(struct in6_addr *a1, struct in6_addr *a2);
 
 #endif /* __CONFIG_H__ */