From 8621ea7d5f05247b0ca01d959a51095f6edd8dc9 Mon Sep 17 00:00:00 2001
From: Kenjiro Nakayama <nakayamakenjiro@gmail.com>
Date: Sun, 22 May 2022 17:44:07 +0900
Subject: [PATCH] Add cgroup_sockopt template for BPF_PROG_TYPE_CGROUP_SOCKOPT

---
 .github/workflows/ci.yml          |  1 +
 cargo-generate.toml               |  6 ++++++
 {{project-name}}-ebpf/src/main.rs | 19 +++++++++++++++++++
 {{project-name}}/src/main.rs      | 11 +++++++++--
 4 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ed4d27e..f06bf15 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -32,6 +32,7 @@ jobs:
           - classifier
           - cgroup_skb
           - cgroup_sysctl
+          - cgroup_sockopt
           - tracepoint
           - lsm
           - tp_btf
diff --git a/cargo-generate.toml b/cargo-generate.toml
index 422f068..567397a 100644
--- a/cargo-generate.toml
+++ b/cargo-generate.toml
@@ -19,6 +19,7 @@ choices = [
     "classifier",
     "cgroup_skb",
     "cgroup_sysctl",
+    "cgroup_sockopt",
     "tracepoint",
     "lsm",
     "tp_btf"
@@ -46,6 +47,11 @@ type = "string"
 prompt = "Attach direction?"
 choices = [ "Ingress", "Egress" ]
 
+[conditional.'program_type == "cgroup_sockopt"'.placeholders.sockopt_target]
+type = "string"
+prompt = "Which socket option?"
+choices = [ "getsockopt", "setsockopt" ]
+
 [conditional.'program_type == "sk_msg"'.placeholders.sock_map]
 type = "string"
 prompt = "Map Name (UPPER_CASE)?"
diff --git a/{{project-name}}-ebpf/src/main.rs b/{{project-name}}-ebpf/src/main.rs
index 906db02..9774bf9 100644
--- a/{{project-name}}-ebpf/src/main.rs
+++ b/{{project-name}}-ebpf/src/main.rs
@@ -303,6 +303,25 @@ unsafe fn try_{{crate_name}}(ctx: SysctlContext) -> Result<i32, i32> {
     info!(&ctx, "sysctl operation called");
     Ok(0)
 }
+{%- when "cgroup_sockopt" %}
+use aya_bpf::{
+    macros::cgroup_sockopt,
+    programs::SockoptContext,
+};
+use aya_log_ebpf::info;
+
+#[cgroup_sockopt({{sockopt_target}},name="{{crate_name}}")]
+pub fn {{crate_name}}(ctx: SockoptContext) -> i32 {
+    match unsafe { try_{{crate_name}}(ctx) } {
+        Ok(ret) => ret,
+        Err(ret) => ret,
+    }
+}
+
+unsafe fn try_{{crate_name}}(ctx: SockoptContext) -> Result<i32, i32> {
+    info!(&ctx, "{{sockopt_target}} called");
+    Ok(0)
+}
 {%- endcase %}
 
 #[panic_handler]
diff --git a/{{project-name}}/src/main.rs b/{{project-name}}/src/main.rs
index f0eaab6..30f02ee 100644
--- a/{{project-name}}/src/main.rs
+++ b/{{project-name}}/src/main.rs
@@ -22,7 +22,9 @@ use aya::programs::{tc, SchedClassifier, TcAttachType};
 {%- when "cgroup_skb" -%}
 use aya::programs::{CgroupSkb, CgroupSkbAttachType};
 {%- when "cgroup_sysctl" -%}
-use aya::programs::{CgroupSysctl};
+use aya::programs::CgroupSysctl;
+{%- when "cgroup_sockopt" -%}
+use aya::programs::CgroupSockopt;
 {%- when "tracepoint" -%}
 use aya::programs::TracePoint;
 {%- when "lsm" -%}
@@ -45,7 +47,7 @@ struct Opt {
     {% if program_type == "xdp" or program_type == "classifier" -%}
     #[clap(short, long, default_value = "eth0")]
     iface: String,
-    {%- elsif program_type == "sock_ops" or program_type == "cgroup_skb" or program_type == "cgroup_sysctl" -%}
+    {%- elsif program_type == "sock_ops" or program_type == "cgroup_skb" or program_type == "cgroup_sysctl" or "cgroup_sockopt" -%}
     #[clap(short, long, default_value = "/sys/fs/cgroup/unified")]
     cgroup_path: String,
     {%- elsif program_type == "uprobe" or program_type == "uretprobe" -%}
@@ -152,6 +154,11 @@ async fn main() -> Result<(), anyhow::Error> {
     let cgroup = std::fs::File::open(opt.cgroup_path)?;
     program.load()?;
     program.attach(cgroup)?;
+    {%- when "cgroup_sockopt" -%}
+    let program: &mut CgroupSockopt = bpf.program_mut("{{crate_name}}").unwrap().try_into()?;
+    let cgroup = std::fs::File::open(opt.cgroup_path)?;
+    program.load()?;
+    program.attach(cgroup)?;
     {%- endcase %}
 
     info!("Waiting for Ctrl-C...");