commit 65f7022461346e47fcbebae130271ab9bdd5e87d
author Maciej Żenczykowski <maze@google.com> Mon Mar 18 14:43:09 2024 -0700
committer Maciej Żenczykowski <maze@google.com> Mon Mar 18 15:02:53 2024 -0700
tree 6f95d526857dd9ea2787a2f21c984b4c1d10e0c8
parent 221b248c6eae0c2e400677f6a211a0a63c56e795

NetBpfLoad: chose bpfloader version at runtime based on Android OS

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Iee55d9c6f828f05d4096dff2e874abc6c41eadeb

netbpfload/NetBpfLoad.cpp

diff --git a/netbpfload/NetBpfLoad.cpp b/netbpfload/NetBpfLoad.cpp
index c6fe9ca..196b687 100644
--- a/netbpfload/NetBpfLoad.cpp
+++ b/netbpfload/NetBpfLoad.cpp
@@ -355,8 +355,11 @@
     // Thus we need to manually create the /sys/fs/bpf/loader subdirectory.
     if (createSysFsBpfSubDir("loader")) return 1;
 
-    // This is Network BpfLoader v0.42
-    const unsigned int bpfloader_ver = 42u;
+    // Version of Network BpfLoader depends on the Android OS version
+    unsigned int bpfloader_ver = 42u;  // [42] BPFLOADER_MAINLINE_VERSION
+    if (isAtLeastT) ++bpfloader_ver;   // [43] BPFLOADER_MAINLINE_T_VERSION
+    if (isAtLeastU) ++bpfloader_ver;   // [44] BPFLOADER_MAINLINE_U_VERSION
+    if (isAtLeastV) ++bpfloader_ver;   // [45] BPFLOADER_MAINLINE_V_VERSION
 
     // Load all ELF objects, create programs and maps, and pin them
     for (const auto& location : locations) {

staticlibs/native/bpf_headers/include/bpf/bpf_helpers.h

diff --git a/staticlibs/native/bpf_headers/include/bpf/bpf_helpers.h b/staticlibs/native/bpf_headers/include/bpf/bpf_helpers.h
index 92ddf44..53c67d5 100644
--- a/staticlibs/native/bpf_headers/include/bpf/bpf_helpers.h
+++ b/staticlibs/native/bpf_headers/include/bpf/bpf_helpers.h
@@ -45,9 +45,19 @@
 //  same time as itself and the rest of the platform)
 #define BPFLOADER_V_VERSION 41u
 
-// Android Mainline - this bpfloader should eventually go back to T
+// Android Mainline - this bpfloader should eventually go back to T (or even S)
+// Note: this value (and the following +1u's) are hardcoded in NetBpfLoad.cpp
 #define BPFLOADER_MAINLINE_VERSION 42u
 
+// Android Mainline BpfLoader when running on Android T
+#define BPFLOADER_MAINLINE_T_VERSION (BPFLOADER_MAINLINE_VERSION + 1u)
+
+// Android Mainline BpfLoader when running on Android U
+#define BPFLOADER_MAINLINE_U_VERSION (BPFLOADER_MAINLINE_T_VERSION + 1u)
+
+// Android Mainline BpfLoader when running on Android V
+#define BPFLOADER_MAINLINE_V_VERSION (BPFLOADER_MAINLINE_U_VERSION + 1u)
+
 /* For mainline module use, you can #define BPFLOADER_{MIN/MAX}_VER
  * before #include "bpf_helpers.h" to change which bpfloaders will
  * process the resulting .o file.