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This allows us to re-enable `code-block-style`.

Switch to `uv` for dependency management; refresh requirements.txt using
`uv pip freeze > requirements.txt`.
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tamird committed Nov 27, 2024
1 parent dd139f7 commit 173df60
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12 changes: 2 additions & 10 deletions .github/workflows/ci.yml
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Expand Up @@ -26,7 +26,6 @@ jobs:

- uses: DavidAnson/markdownlint-cli2-action@v18
with:
config: .markdownlint.json
globs: '**/*.md'

- uses: dtolnay/rust-toolchain@nightly
Expand Down Expand Up @@ -54,16 +53,9 @@ jobs:
with:
tool: bpf-linker

- name: Set up Python
uses: actions/setup-python@v5
- uses: astral-sh/setup-uv@v3

- name: Install python dependencies
run: |
python -m pip install --upgrade pip
if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
- name: Build docs
run: mkdocs build
- run: uv run mkdocs build

- name: Check Examples
working-directory: examples
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3 changes: 0 additions & 3 deletions .markdownlint.json

This file was deleted.

1 change: 1 addition & 0 deletions .python-version
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@@ -0,0 +1 @@
3.8
9 changes: 3 additions & 6 deletions README.md
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Expand Up @@ -11,12 +11,9 @@ This book is a living document, and is updated continuously.

## Local Render

```console
virtualenv .venv
source .venv/bin/activate
pip install -r requirements.txt
mkdocs serve
```
```console
uv run mkdocs serve
```

## License

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22 changes: 11 additions & 11 deletions docs/book/aya/aya-tool.md
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@@ -1,9 +1,7 @@
# Using aya-tool

!!! example "Source Code"

Full code for the example in this chapter is available
[here](https://github.com/aya-rs/book/tree/main/examples/aya-tool)
> [!EXAMPLE] Source Code
> Full code for the example in this chapter is available [here][source-code].
Very often you will need to use type definitions that your running Linux kernel
uses in its source code. For example, you might need a definition of
Expand Down Expand Up @@ -53,13 +51,14 @@ done with:
aya-tool generate task_struct > myapp-ebpf/src/vmlinux.rs
```

!!! tip "Generating for multiple types"

You can also specify multiple types to generate, for example:
```console
$ aya-tool generate task_struct dentry > vmlinux.rs
```
But in the following example, we will focus only on `task_struct`.
> [!TIP] Generating for multiple types
> You can also specify multiple types to generate, for example:
>
> ```console
> aya-tool generate task_struct dentry > vmlinux.rs
> ```
>
> But in the following example, we will focus only on `task_struct`.
Then we can use `vmlinux` as a module with `mod vmlinux` in our eBPF program,
like here:
Expand All @@ -77,4 +76,5 @@ The structures are not simply generated from kernel headers. However, the
target kernel (regardless of version) should have `CONFIG_DEBUG_INFO_BTF`
option enabled.

[source-code]: https://github.com/aya-rs/book/tree/main/examples/aya-tool
[task-struct]: https://elixir.bootlin.com/linux/v5.15.3/source/include/linux/sched.h#L723
11 changes: 8 additions & 3 deletions docs/book/programs/cgroup-skb.md
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@@ -1,8 +1,7 @@
# Cgroup SKB

!!! example "Source Code"

Full code for the example in this chapter is available [here](https://github.com/aya-rs/book/tree/main/examples/cgroup-skb-egress)
> [!EXAMPLE] Source Code
> Full code for the example in this chapter is available [here][source-code].
## What is Cgroup SKB?

Expand Down Expand Up @@ -47,6 +46,8 @@ cargo install bindgen-cli
Let's use `xtask` to automate the process of generating bindings so we can
easily reproduce it in the future by adding the following code:

<!-- markdownlint-disable MD046 -->

=== "xtask/src/codegen.rs"

```rust linenums="1"
Expand All @@ -65,6 +66,8 @@ easily reproduce it in the future by adding the following code:
--8<-- "examples/cgroup-skb-egress/xtask/src/main.rs"
```

<!-- markdownlint-enable MD046 -->

Once we've generated our file using `cargo xtask codegen` from the root of the
project, we can access it by including `mod bindings` from eBPF code.

Expand Down Expand Up @@ -169,3 +172,5 @@ LOG: DST 172.217.19.78, ACTION 1
LOG: DST 172.217.19.78, ACTION 1
LOG: DST 172.217.19.78, ACTION 1
```

[source-code]: https://github.com/aya-rs/book/tree/main/examples/cgroup-skb-egress
57 changes: 28 additions & 29 deletions docs/book/programs/classifiers.md
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@@ -1,9 +1,7 @@
# Classifiers

!!! example "Source Code"

Full code for the example in this chapter is available
[here](https://github.com/aya-rs/book/tree/main/examples/tc-egress)
> [!EXAMPLE] Source Code
> Full code for the example in this chapter is available [here][source-code].
## What is Classifier in eBPF?

Expand Down Expand Up @@ -48,18 +46,17 @@ packet. Otherwise, we are going to **pipe** it with `TC_ACT_PIPE` action - which
means allowing it on our side, but let the packet be inspected also by another
Classifier programs and qdisc filters.

!!! note "TC_ACT_OK"

There is also a possibility to allow the packet while bypassing the other
programs and filters - `TC_ACT_OK`. We recommend that option only if absolutely
sure that you want your program to have a precedence over the other programs
or filters.
> [!NOTE] TC_ACT_OK
> There is also a possibility to allow the packet while bypassing the other
> programs and filters - `TC_ACT_OK`. We recommend that option only if absolutely
> sure that you want your program to have a precedence over the other programs
> or filters.
Here's how the eBPF code looks like:

```rust linenums="1" title="tc-egress-ebpf/src/main.rs"
--8<-- "examples/tc-egress/tc-egress-ebpf/src/main.rs"
```
```rust linenums="1" title="tc-egress-ebpf/src/main.rs"
--8<-- "examples/tc-egress/tc-egress-ebpf/src/main.rs"
```

1. Create our map.
1. Check if we should allow or deny our packet.
Expand All @@ -74,9 +71,9 @@ In this example, we'll block all egress traffic going to `1.1.1.1`.

Here's how the code looks like:

```rust linenums="1" title="tc-egress/src/main.rs"
--8<-- "examples/tc-egress/tc-egress/src/main.rs"
```
```rust linenums="1" title="tc-egress/src/main.rs"
--8<-- "examples/tc-egress/tc-egress/src/main.rs"
```

1. Get a reference to the map.
1. Create an IPv4Addr.
Expand All @@ -90,16 +87,18 @@ is an appropriate type to use in eBPF maps.

## Running the program

```console
$ RUST_LOG=info cargo xtask run
LOG: SRC 1.1.1.1, ACTION 2
LOG: SRC 35.186.224.47, ACTION 3
LOG: SRC 35.186.224.47, ACTION 3
LOG: SRC 1.1.1.1, ACTION 2
LOG: SRC 168.100.68.32, ACTION 3
LOG: SRC 168.100.68.239, ACTION 3
LOG: SRC 168.100.68.32, ACTION 3
LOG: SRC 168.100.68.239, ACTION 3
LOG: SRC 1.1.1.1, ACTION 2
LOG: SRC 13.248.212.111, ACTION 3
```
```console
$ RUST_LOG=info cargo xtask run
LOG: SRC 1.1.1.1, ACTION 2
LOG: SRC 35.186.224.47, ACTION 3
LOG: SRC 35.186.224.47, ACTION 3
LOG: SRC 1.1.1.1, ACTION 2
LOG: SRC 168.100.68.32, ACTION 3
LOG: SRC 168.100.68.239, ACTION 3
LOG: SRC 168.100.68.32, ACTION 3
LOG: SRC 168.100.68.239, ACTION 3
LOG: SRC 1.1.1.1, ACTION 2
LOG: SRC 13.248.212.111, ACTION 3
```

[source-code]: https://github.com/aya-rs/book/tree/main/examples/tc-egress
7 changes: 3 additions & 4 deletions docs/book/programs/lsm.md
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@@ -1,9 +1,7 @@
# LSM

!!! example "Source Code"

Full code for the example in this chapter is available
[here](https://github.com/aya-rs/book/tree/main/examples/lsm-nice)
> [!EXAMPLE] Source Code
> Full code for the example in this chapter is available [here][source-code].
## What is LSM

Expand Down Expand Up @@ -204,6 +202,7 @@ renice: failed to set priority for 587184 (process ID): Operation not permitted
If doing that resulted in `Operation not permitted`, congratulations, your LSM
eBPF program works!

[source-code]: https://github.com/aya-rs/book/tree/main/examples/lsm-nice
[lsm-wikipedia]: https://en.wikipedia.org/wiki/Linux_Security_Modules
[lsm-kernel-docs]: https://www.kernel.org/doc/html/latest/security/lsm.html
[lsm-hook-defs]: https://github.com/torvalds/linux/blob/master/include/linux/lsm_hook_defs.h
Expand Down
7 changes: 3 additions & 4 deletions docs/book/programs/probes.md
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@@ -1,9 +1,7 @@
# Probes

!!! example "Source Code"

Full code for the example in this chapter is available
[here](https://github.com/aya-rs/book/tree/main/examples/kprobetcp).
> [!EXAMPLE] Source Code
> Full code for the example in this chapter is available [here][source-code].
## What are the probes in eBPF?

Expand Down Expand Up @@ -67,5 +65,6 @@ $ RUST_LOG=info cargo xtask run --release

<!-- markdownlint-enable MD013 -->

[source-code]: https://github.com/aya-rs/book/tree/main/examples/kprobetcp
[kernel-docs]: https://docs.kernel.org/trace/kprobes.html
[tcp-connect]: https://elixir.bootlin.com/linux/latest/source/net/ipv4/tcp_output.c#L3837
39 changes: 19 additions & 20 deletions docs/book/programs/xdp.md
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@@ -1,8 +1,7 @@
# XDP

!!! example "Source Code"

Full code for the example in this chapter is available [here](https://github.com/aya-rs/book/tree/main/examples/xdp-drop)
> [!EXAMPLE] Source Code
> Full code for the example in this chapter is available [here][source-code].
## What is XDP in eBPF?

Expand Down Expand Up @@ -128,8 +127,8 @@ We import the necessary dependencies:
- `core::mem`: For memory manipulation
- `network_types`: For Ethernet and IP header definitions

!!! note "Important"
Make sure you add the `network_types` dependency in your `Cargo.toml`.
> [!IMPORTANT]
> Make sure you add the `network_types` dependency in your `Cargo.toml`.
Here's how the code looks:

Expand Down Expand Up @@ -413,16 +412,15 @@ human-readable and can be easily converted to a u32.

We'll block all traffic originating from `1.1.1.1` in this example.

!!! note "Endianness"

IP addresses are always encoded in network byte order (big endian) within
packets. In our eBPF program, before checking the blocklist, we convert them
to host endian using `u32::from_be`. Therefore it's correct to write our IP
addresses in host endian format from userspace.

The other approach would work too: we could convert IPs to network endian
when inserting from userspace, and then we wouldn't need to convert when
indexing from the eBPF program.
> [!NOTE] Endianness
> IP addresses are always encoded in network byte order (big endian) within
> packets. In our eBPF program, before checking the blocklist, we convert them
> to host endian using `u32::from_be`. Therefore it's correct to write our IP
> addresses in host endian format from userspace.
>
> The other approach would work too: we could convert IPs to network endian
> when inserting from userspace, and then we wouldn't need to convert when
> indexing from the eBPF program.
Let's begin with writing the user-space code:

Expand Down Expand Up @@ -455,11 +453,11 @@ we use for informational and warning messages
- `tokio::signal`: For handling signals asynchronously, see
[this link][tokio-signal] for more information

!!! note
`aya::Bpf` is deprecated since version `0.13.0` and `aya_log:BpfLogger`
since `0.2.1`. Use [`aya::Ebpf`][aya-ebpf] and
[`aya_log:EbpfLogger`][aya-ebpf-logger] instead if you are using the more
recent versions.
> [!NOTE]
> `aya::Bpf` is deprecated since version `0.13.0` and `aya_log:BpfLogger`
> since `0.2.1`. Use [`aya::Ebpf`][aya-ebpf] and
> [`aya_log:EbpfLogger`][aya-ebpf-logger] instead if you are using the more
> recent versions.
#### Defining command-line arguments

Expand Down Expand Up @@ -628,6 +626,7 @@ RUST_LOG=info cargo xtask run -- --iface <interface>
if you want to provide another network interface name. note that you can also
use `cargo xtask run` without the rest, but you won't get any logging.

[source-code]: https://github.com/aya-rs/book/tree/main/examples/xdp-drop
[af-xdp]: https://www.kernel.org/doc/html/latest/networking/af_xdp.html
[kernel-documentation]: https://www.kernel.org/doc/html/latest/networking/af_xdp.html
[cilium-xdp]: https://docs.cilium.io/en/latest/bpf/progtypes/#xdp
Expand Down
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