/* $NetBSD: exec.c,v 1.26 2024/09/19 06:26:11 mlelstv Exp $ */

/*-
 * Copyright (c) 2019 Jason R. Thorpe
 * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "efiboot.h"
#ifdef EFIBOOT_FDT
#include "efifdt.h"
#endif
#ifdef EFIBOOT_ACPI
#include "efiacpi.h"
#endif
#include "efirng.h"
#include "module.h"

#include <sys/param.h>
#include <sys/reboot.h>

extern char twiddle_toggle;

u_long load_offset = 0;

EFI_PHYSICAL_ADDRESS efirng_addr;
u_long efirng_size = 0;

int
load_file(const char *path, u_long extra, bool quiet_errors,
    EFI_PHYSICAL_ADDRESS *paddr, u_long *psize)
{
        EFI_STATUS status;
        struct stat st;
        ssize_t len;
        ssize_t expectedlen;
        int fd;

        if (strlen(path) == 0)
                return 0;

        fd = open(path, 0);
        if (fd < 0) {
                if (!quiet_errors) {
                        printf("boot: failed to open %s: %s\n", path,
                            strerror(errno));
                }
                return errno;
        }
        if (fstat(fd, &st) < 0) {
                printf("boot: failed to fstat %s: %s\n", path, strerror(errno));
                close(fd);
                return errno;
        }
        if (st.st_size == 0) {
                if (!quiet_errors) {
                        printf("boot: empty file %s\n", path);
                }
                close(fd);
                return EINVAL;
        }

        expectedlen = st.st_size;
        *psize = st.st_size + extra;

#ifdef EFIBOOT_ALLOCATE_MAX_ADDRESS
        *paddr = EFIBOOT_ALLOCATE_MAX_ADDRESS;
        status = uefi_call_wrapper(BS->AllocatePages, 4, AllocateMaxAddress, EfiLoaderData,
            EFI_SIZE_TO_PAGES(*psize), paddr);
#else
        *paddr = 0;
        status = uefi_call_wrapper(BS->AllocatePages, 4, AllocateAnyPages, EfiLoaderData,
            EFI_SIZE_TO_PAGES(*psize), paddr);
#endif
        if (EFI_ERROR(status)) {
                printf("Failed to allocate %lu bytes for %s (error %lu)\n",
                    *psize, path, (u_long)status);
                close(fd);
                *paddr = 0;
                return ENOMEM;
        }

        printf("boot: loading %s ", path);
        len = read(fd, (void *)(uintptr_t)*paddr, expectedlen);
        close(fd);

        if (len != expectedlen) {
                if (len < 0) {
                        printf(": %s\n", strerror(errno));
                } else {
                        printf(": returned %zd (expected %zd)\n", len,
                            expectedlen);
                }
                return EIO;
        }

        printf("done.\n");

        efi_dcache_flush(*paddr, *psize);

        return 0;
}

static void
generate_efirng(void)
{
        EFI_PHYSICAL_ADDRESS addr;
        u_long size = EFI_PAGE_SIZE;
        EFI_STATUS status;

        /* Check whether the RNG is available before bothering.  */
        if (!efi_rng_available())
                return;

        /*
         * Allocate a page.  This is the smallest unit we can pass into
         * the kernel conveniently.
         */
#ifdef EFIBOOT_ALLOCATE_MAX_ADDRESS
        addr = EFIBOOT_ALLOCATE_MAX_ADDRESS;
        status = uefi_call_wrapper(BS->AllocatePages, 4, AllocateMaxAddress,
            EfiLoaderData, EFI_SIZE_TO_PAGES(size), &addr);
#else
        addr = 0;
        status = uefi_call_wrapper(BS->AllocatePages, 4, AllocateAnyPages,
            EfiLoaderData, EFI_SIZE_TO_PAGES(size), &addr);
#endif
        if (EFI_ERROR(status)) {
                Print(L"Failed to allocate page for EFI RNG output: %r\n",
                    status);
                return;
        }

        /* Fill the page with whatever the EFI RNG will do.  */
        if (efi_rng((void *)(uintptr_t)addr, size)) {
                uefi_call_wrapper(BS->FreePages, 2, addr,
                    EFI_SIZE_TO_PAGES(size));
                return;
        }

        /* Success!  */
        efirng_addr = addr;
        efirng_size = size;
}

int
exec_netbsd(const char *fname, const char *args)
{
        EFI_PHYSICAL_ADDRESS addr;
        u_long marks[MARK_MAX], alloc_size;
        EFI_STATUS status;
        int fd, ohowto;

        twiddle_toggle = 0;

        generate_efirng();

        memset(marks, 0, sizeof(marks));
        ohowto = howto;
        howto |= AB_SILENT;
        fd = loadfile(fname, marks, COUNT_KERNEL | LOAD_NOTE);
        howto = ohowto;
        if (fd < 0) {
                printf("boot: %s: %s\n", fname, strerror(errno));
                return EIO;
        }
        close(fd);
        marks[MARK_END] = (((u_long) marks[MARK_END] + sizeof(int) - 1)) & -sizeof(int);
        alloc_size = marks[MARK_END] - marks[MARK_START] + efi_fdt_alloc_size() + EFIBOOT_ALIGN;

#ifdef EFIBOOT_ALLOCATE_MAX_ADDRESS
        addr = EFIBOOT_ALLOCATE_MAX_ADDRESS;
        status = uefi_call_wrapper(BS->AllocatePages, 4, AllocateMaxAddress, EfiLoaderData,
            EFI_SIZE_TO_PAGES(alloc_size), &addr);
#else
        addr = 0;
        status = uefi_call_wrapper(BS->AllocatePages, 4, AllocateAnyPages, EfiLoaderData,
            EFI_SIZE_TO_PAGES(alloc_size), &addr);
#endif
        if (EFI_ERROR(status)) {
                printf("Failed to allocate %lu bytes for kernel image (error %lu)\n",
                    alloc_size, (u_long)status);
                return ENOMEM;
        }

        memset(marks, 0, sizeof(marks));
        load_offset = (addr + EFIBOOT_ALIGN - 1) & -EFIBOOT_ALIGN;
        fd = loadfile(fname, marks, LOAD_KERNEL);
        if (fd < 0) {
                printf("boot: %s: %s\n", fname, strerror(errno));
                goto cleanup;
        }
        close(fd);
        load_offset = 0;

        if (efi_fdt_prepare_boot(fname, args, marks) != 0) {
                goto cleanup;
        }

        efi_boot_kernel(marks);

        /* This should not happen.. */
        printf("boot returned\n");

cleanup:
        uefi_call_wrapper(BS->FreePages, 2, addr, EFI_SIZE_TO_PAGES(alloc_size));
        efi_fdt_cleanup_boot();

        return EIO;
}