port c init to rust

.gitignore

@@ -1,3 +1,4 @@
 out/*
 cache/*
 .*
+src/init/target

Makefile

@@ -218,6 +218,7 @@ define toolchain
 		--env KBUILD_BUILD_TIMESTAMP=$(KBUILD_BUILD_TIMESTAMP) \
 		--env KCONFIG_NOTIMESTAMP=$(KCONFIG_NOTIMESTAMP) \
 		--env SOURCE_DATE_EPOCH=$(SOURCE_DATE_EPOCH) \
+		--env CARGO_HOME=/cache/cargo \
 		local/$(NAME)-build \
 		bash -c $(2)
 endef
@@ -250,12 +251,12 @@ $(OUT_DIR)/busybox: \
 
 $(OUT_DIR)/init:
 	$(call toolchain,$(USER)," \
-		gcc \
+		cd /src/init/ && \
-			-static \
+		RUSTFLAGS='-C target-feature=+crt-static' cargo build --release && \
-			-static-libgcc /src/init/init.c \
+		cp /src/init/target/release/init /out/init \
-			-o /out/init; \
 	")
 
+
 $(CACHE_DIR)/linux-$(LINUX_VERSION)/usr/gen_init_cpio: \
 	$(CACHE_DIR)/linux-$(LINUX_VERSION) \
 	$(CACHE_DIR)/linux-$(LINUX_VERSION) \
@@ -269,21 +270,17 @@ $(CACHE_DIR)/linux-$(LINUX_VERSION)/usr/gen_init_cpio: \
 $(OUT_DIR)/$(TARGET)/rootfs.cpio: \
 	$(OUT_DIR)/busybox \
 	$(OUT_DIR)/init \
+	$(OUT_DIR)/aws/nsm.ko \
 	$(CACHE_DIR)/linux-$(LINUX_VERSION)/usr/gen_init_cpio
-	mkdir -p $(CACHE_DIR)/$(TARGET)/rootfs/bin
+	cp $(CONFIG_DIR)/$(TARGET)/rootfs.list $(CACHE_DIR)/$(TARGET)/rootfs.list
-	cp $(CONFIG_DIR)/generic/rootfs.list $(CACHE_DIR)/$(TARGET)/rootfs.list
+	cp $(OUT_DIR)/init $(CACHE_DIR)/$(TARGET)/rootfs/init
 ifeq ($(DEBUG), true)
-	cp $(OUT_DIR)/init $(CACHE_DIR)/$(TARGET)/rootfs/real_init
+	mv $(CACHE_DIR)/$(TARGET)/rootfs/init $(CACHE_DIR)/$(TARGET)/rootfs/real_init
 	cp $(SRC_DIR)/scripts/busybox_init $(CACHE_DIR)/$(TARGET)/rootfs/init
+	mkdir -p $(CACHE_DIR)/$(TARGET)/rootfs/bin
 	cp $(OUT_DIR)/busybox $(CACHE_DIR)/$(TARGET)/rootfs/bin/
 	echo "file /bin/busybox /cache/rootfs/bin/busybox 0755 0 0" \
 		>> $(CACHE_DIR)/$(TARGET)/rootfs.list
-else
-	cp $(OUT_DIR)/init $(CACHE_DIR)/$(TARGET)/rootfs/init
-endif
-ifeq ($(TARGET), aws)
-	echo "file /nsm.ko /out/aws/nsm.ko 0755 0 0" \
-		>> $(CACHE_DIR)/$(TARGET)/rootfs.list
 endif
 	$(call toolchain,$(USER)," \
 		cd /cache/$(TARGET)/rootfs && \
@@ -294,11 +291,11 @@ endif
 			-o /out/$(TARGET)/rootfs.cpio \
 			/cache/$(TARGET)/rootfs.list && \
 		cpio -itv < /out/$(TARGET)/rootfs.cpio && \
-		sha256sum /out/rootfs.cpio; \
+		sha256sum /out/$(TARGET)/rootfs.cpio; \
 	")
 
 $(OUT_DIR)/$(TARGET)/bzImage: \
-	$(OUT_DIR)/rootfs.cpio
+	$(OUT_DIR)/$(TARGET)/rootfs.cpio
 	$(call toolchain,$(USER)," \
 		cd /cache/linux-$(LINUX_VERSION) && \
 		cp /config/$(TARGET)/linux.config .config && \
@@ -332,14 +329,14 @@ endif
 $(OUT_DIR)/aws/nitro.eif: \
 	$(OUT_DIR)/aws/eif_build \
 	$(OUT_DIR)/$(TARGET)/bzImage \
-	$(OUT_DIR)/rootfs.cpio
+	$(OUT_DIR)/$(TARGET)/rootfs.cpio
 ifeq ($(TARGET), aws)
 	$(call toolchain,$(USER)," \
 		/out/eif_build \
 			--kernel /out/$(TARGET)/bzImage \
 			--kernel_config /config/$(TARGET)/linux.config \
 			--cmdline 'reboot=k initrd=0x2000000$(,)3228672 root=/dev/ram0 panic=1 pci=off nomodules console=ttyS0 i8042.noaux i8042.nomux i8042.nopnp i8042.dumbkbd' \
-			--ramdisk /out/rootfs.cpio \
+			--ramdisk /out/aws/rootfs.cpio \
 			--output /out/aws/nitro.eif; \
 	")
 endif

config/aws/rootfs.list

@@ -0,0 +1,12 @@
+dir  /dev                                               0755 0 0
+nod  /dev/console                                       0600 0 0 c 5 1
+dir  /sys                                               0755 0 0
+dir  /usr                                               0755 0 0
+dir  /etc                                               0755 0 0
+dir  /proc                                              0755 0 0
+dir  /bin                                               0755 0 0
+dir  /sbin                                              0755 0 0
+dir  /usr/bin                                           0755 0 0
+dir  /usr/sbin                                          0755 0 0
+file /init         /cache/aws/rootfs/init               0755 0 0
+file /nsm.ko       /out/aws/nsm.ko                      0755 0 0

src/init/Cargo.lock

@@ -0,0 +1,16 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "init"
+version = "0.1.0"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.134"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "329c933548736bc49fd575ee68c89e8be4d260064184389a5b77517cddd99ffb"

src/init/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "init"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+libc = "0.2.134"
+
+[[bin]]
+name = "init"
+path = "init.rs"

src/init/init.c

@@ -1,189 +0,0 @@
-#define _GNU_SOURCE
-#include <errno.h>
-#include <fcntl.h>
-#include <getopt.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/mount.h>
-#include <sys/reboot.h>
-#include <sys/socket.h>
-#include <sys/stat.h>
-#include <sys/syscall.h>
-#include <sys/sysmacros.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <unistd.h>
-#include <linux/vm_sockets.h>
-#include <poll.h>
-
-_Noreturn void die(const char *msg);
-#define die_on(CONDITION, ...) \
-    do { \
-        if (CONDITION) { \
-            die(__VA_ARGS__); \
-        } \
-    } while (0)
-
-#define finit_module(fd, param_values, flags) (int)syscall(__NR_finit_module, fd, param_values, flags)
-#define DEFAULT_PATH_ENV "PATH=/sbin:/usr/sbin:/bin:/usr/bin"
-#define NSM_PATH "nsm.ko"
-#define TIMEOUT 20000
-#define VSOCK_PORT 9000
-#define VSOCK_CID 3
-#define HEART_BEAT 0xB7
-
-const char *const default_envp[] = {
-    DEFAULT_PATH_ENV,
-    NULL,
-};
-
-const char *const default_argv[] = { "sh", NULL };
-
-struct Mount {
-    const char *source, *target, *type;
-    unsigned long flags;
-    const void *data;
-};
-
-struct Mkdir {
-    const char *path;
-    mode_t mode;
-};
-
-struct Mknod {
-    const char *path;
-    mode_t mode;
-    int major, minor;
-};
-
-struct Symlink {
-    const char *linkpath, *target;
-};
-
-enum OpType {
-    OpMount,
-    OpMkdir,
-    OpMknod,
-    OpSymlink,
-};
-
-struct InitOp {
-    enum OpType op;
-    union {
-        struct Mount mount;
-        struct Mkdir mkdir;
-        struct Mknod mknod;
-        struct Symlink symlink;
-    };
-};
-
-const struct InitOp ops[] = {
-    { OpMount, .mount = { "proc", "/proc", "proc", MS_NODEV | MS_NOSUID | MS_NOEXEC } },
-    { OpSymlink, .symlink = { "/dev/fd", "/proc/self/fd" } },
-    { OpSymlink, .symlink = { "/dev/stdin", "/proc/self/fd/0" } },
-    { OpSymlink, .symlink = { "/dev/stdout", "/proc/self/fd/1" } },
-    { OpSymlink, .symlink = { "/dev/stderr", "/proc/self/fd/2" } },
-    { OpMkdir, .mkdir = { "/dev/shm", 0755 } },
-    { OpMkdir, .mkdir = { "/dev/pts", 0755 } },
-    { OpMount, .mount = { "devpts", "/dev/pts", "devpts", MS_NOSUID | MS_NOEXEC } },
-    { OpMount, .mount = { "sysfs", "/sys", "sysfs", MS_NODEV | MS_NOSUID | MS_NOEXEC } },
-};
-
-void warn(const char *msg) {
-    int error = errno;
-    perror(msg);
-    errno = error;
-}
-
-void warn2(const char *msg1, const char *msg2) {
-    int error = errno;
-    fputs(msg1, stderr);
-    fputs(": ", stderr);
-    errno = error;
-    warn(msg2);
-}
-
-_Noreturn void dien() {
-    exit(errno);
-}
-
-_Noreturn void die(const char *msg) {
-    warn(msg);
-    dien();
-}
-
-_Noreturn void die2(const char *msg1, const char *msg2) {
-    warn2(msg1, msg2);
-    dien();
-}
-
-void init_dev() {
-    if (mount("dev", "/dev", "devtmpfs", MS_NOSUID | MS_NOEXEC, NULL) < 0) {
-        warn2("mount", "/dev");
-        if (errno != EBUSY) {
-            dien();
-        }
-    }
-}
-
-void init_console() {
-    const char *console_path = "/dev/console";
-    die_on(freopen(console_path, "r", stdin) == NULL,
-           "freopen failed for stdin");
-    die_on(freopen(console_path, "w", stdout) == NULL,
-           "freopen failed for stdout");
-    die_on(freopen(console_path, "w", stderr) == NULL,
-           "freopen failed for stderr");
-}
-
-void enclave_ready() {
-    int socket_fd;
-    struct sockaddr_vm sa = {
-        .svm_family = AF_VSOCK,
-        .svm_cid = VSOCK_CID,
-        .svm_port = VSOCK_PORT,
-        .svm_reserved1 = 0,
-    };
-
-    uint8_t buf[1];
-    buf[0] = HEART_BEAT;
-    errno = -EINVAL;
-
-    socket_fd = socket(AF_VSOCK, SOCK_STREAM, 0);
-    die_on(socket_fd < 0, "socket");
-    die_on(connect(socket_fd, (struct sockaddr*) &sa, sizeof(sa)), "connect");
-    die_on(write(socket_fd, buf, 1) != 1, "write heartbeat");
-    die_on(read(socket_fd, buf, 1) != 1, "read heartbeat");
-    die_on(buf[0] != HEART_BEAT, "received wrong heartbeat");
-    die_on(close(socket_fd), "close");
-}
-
-void init_nsm_driver() {
-    int fd;
-    int rc;
-
-    fd = open(NSM_PATH, O_RDONLY | O_CLOEXEC);
-    if (fd < 0 && errno == ENOENT) {
-        return;
-    }
-    die_on(fd < 0, "failed to open nsm fd");
-    rc = finit_module(fd, "", 0);
-    die_on(rc < 0, "failed to insert nsm driver");
-
-    die_on(close(fd), "close nsm fd");
-    rc = unlink(NSM_PATH);
-    if (rc < 0)
-        warn("Could not unlink " NSM_PATH);
-}
-
-int main() {
-    init_dev();
-    init_console();
-    init_nsm_driver();
-    enclave_ready();
-    puts("\nHello World with NSM!\n");
-    reboot(RB_AUTOBOOT);
-}

src/init/init.rs

@@ -0,0 +1,65 @@
+extern crate libc;
+use libc::mount;
+use libc::read;
+use libc::write;
+use libc::close;
+use libc::reboot;
+use libc::socket;
+use libc::connect;
+use libc::freopen;
+use libc::fdopen;
+use libc::c_void;
+use libc::sockaddr;
+use libc::sockaddr_vm;
+use libc::SOCK_STREAM;
+use libc::AF_VSOCK;
+use libc::MS_NOSUID;
+use libc::MS_NOEXEC;
+use libc::RB_AUTOBOOT;
+use std::mem::zeroed;
+use std::mem::size_of;
+
+fn main() {
+    unsafe {
+        mount(
+            b"devtmpfs\0".as_ptr() as _,
+            b"/dev\0".as_ptr() as _,
+            b"devtmpfs\0".as_ptr() as _,
+            MS_NOSUID | MS_NOEXEC,
+            b"mode=0755\0".as_ptr() as *const c_void,
+        );
+        freopen(
+            b"/dev/console\0".as_ptr() as _,
+            b"r\0".as_ptr() as _,
+            fdopen(0, b"r\0".as_ptr() as *const i8)
+        );
+        freopen(
+            b"/dev/console\0".as_ptr() as _,
+            b"w\0".as_ptr() as _,
+            fdopen(1, b"w\0".as_ptr() as *const i8)
+        );
+        freopen(
+            b"/dev/console\0".as_ptr() as _,
+            b"w\0".as_ptr() as _,
+
+            fdopen(2, b"w\0".as_ptr() as *const i8)
+        );
+        let mut sa: sockaddr_vm = zeroed();
+        sa.svm_family = AF_VSOCK as _;
+        sa.svm_port = 9000;
+        sa.svm_cid = 3;
+        let fd = socket(AF_VSOCK, SOCK_STREAM, 0);
+        connect(
+            fd,
+            &sa as *const _ as *mut sockaddr,
+            size_of::<sockaddr_vm>() as _,
+        );
+        let mut buf: [u8; 1] = [0; 1];
+        buf[0] = 0xB7;
+        write(fd, buf.as_ptr() as _, 1);
+        read(fd, buf.as_ptr() as _, 1);
+        close(fd);
+        println!("Hello World from Rust init!");
+        reboot(RB_AUTOBOOT);
+    }
+}