Add a eBPF map to store iface name and index

Since the kernel bpf program can only get the iface index instead of
iface name, we need a seperate map to store the iface index and name
pair in userspace so the kernel program can know what iface each
received packet is and account against the correct name.

Test: run cts -m TrafficStatsTest
Bug: 30950746
Bug: 73137611
Change-Id: I6638dc4b03db6fd18b6b38b4524ec89e25a55bc0

1 files changed, 20 insertions, 0 deletions

diff --git a/server/InterfaceController.cpp b/server/InterfaceController.cpp
index 28b814f2..5a630255 100644
--- a/server/InterfaceController.cpp
+++ b/server/InterfaceController.cpp
@@ -17,6 +17,7 @@
 #include <dirent.h>
 #include <errno.h>
 #include <malloc.h>
+#include <net/if.h>
 #include <sys/socket.h>
 
 #include <functional>
@@ -386,3 +387,22 @@ void InterfaceController::setIPv6OptimisticMode(const char *value) {
     setOnAllInterfaces(ipv6_proc_path, "optimistic_dad", value);
     setOnAllInterfaces(ipv6_proc_path, "use_optimistic", value);
 }
+
+StatusOr<std::map<std::string, uint32_t>> InterfaceController::getIfaceList() {
+    std::map<std::string, uint32_t> ifacePairs;
+    DIR* d;
+    struct dirent* de;
+
+    if (!(d = opendir("/sys/class/net"))) {
+        return statusFromErrno(errno, "Cannot open iface directory");
+    }
+    while ((de = readdir(d))) {
+        if (de->d_name[0] == '.') continue;
+        uint32_t ifaceIndex = if_nametoindex(de->d_name);
+        if (ifaceIndex) {
+          ifacePairs.insert(std::pair<std::string, uint32_t>(de->d_name, ifaceIndex));
+        } 
+    }
+    closedir(d);
+    return ifacePairs;
+}