/*-
 * Copyright (c) 2016-2021 Netflix, Inc.
 *
 * 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 AUTHOR 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 AUTHOR 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 <sys/cdefs.h>
#include <ctype.h>
#include <efivar.h>
#include <efivar-dp.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "efiutil.h"
#include "efichar.h"

/* options descriptor */
static struct option longopts[] = {
        { "append",             no_argument,            NULL,   'a' },
        { "ascii",              no_argument,            NULL,   'A' },
        { "attributes",         required_argument,      NULL,   't' },
        { "binary",             no_argument,            NULL,   'b' },
        { "delete",             no_argument,            NULL,   'D' },
        { "device",             no_argument,            NULL,   'd' },
        { "device-path",        no_argument,            NULL,   'd' },
        { "fromfile",           required_argument,      NULL,   'f' },
        { "guid",               no_argument,            NULL,   'g' },
        { "hex",                no_argument,            NULL,   'H' },
        { "list-guids",         no_argument,            NULL,   'L' },
        { "list",               no_argument,            NULL,   'l' },
        { "load-option",        no_argument,            NULL,   'O' },
        { "name",               required_argument,      NULL,   'n' },
        { "no-name",            no_argument,            NULL,   'N' },
        { "print",              no_argument,            NULL,   'p' },
//      { "print-decimal",      no_argument,            NULL,   'd' }, /* unimplemnted clash with linux version */
        { "quiet",              no_argument,            NULL,   'q' },
        { "raw-guid",           no_argument,            NULL,   'R' },
        { "utf8",               no_argument,            NULL,   'u' },
        { "write",              no_argument,            NULL,   'w' },
        { NULL,                 0,                      NULL,   0 }
};


static bool aflag, Aflag, bflag, dflag, Dflag, gflag, Hflag, Nflag,
        lflag, Lflag, Rflag, wflag, pflag, uflag, load_opt_flag, quiet;
static char *varname;
static char *fromfile;
static u_long attrib = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS;

static void
usage(void)
{

        errx(1, "efivar [-abdDHlLNpqRtuw] [-n name] [-f file] [--append] [--ascii]\n"
            "\t[--attributes] [--binary] [--delete] [--fromfile file] [--hex]\n"
            "\t[--list-guids] [--list] [--load-option] [--name name] [--no-name]\n"
            "\t[--print] [--print-decimal] [--raw-guid] [--utf8] [--write]\n"
            "\t[--quiet]\n"
            "\tname[=value]");
}

static void
rep_err(int eval, const char *fmt, ...)
{
        va_list ap;

        if (quiet)
                exit(eval);

        va_start(ap, fmt);
        verr(eval, fmt, ap);
        va_end(ap);
}

static void
rep_errx(int eval, const char *fmt, ...)
{
        va_list ap;

        if (quiet)
                exit(eval);

        va_start(ap, fmt);
        verrx(eval, fmt, ap);
        va_end(ap);
}

static void
breakdown_name(char *name, efi_guid_t *guid, char **vname)
{
        char *cp, *ocp;

        ocp = NULL;
        while (true) {
                cp = strrchr(name, '-');
                if (cp == NULL) {
                        if (ocp != NULL)
                                *ocp = '-';
                        rep_errx(1, "Invalid guid in: %s", name);
                }
                if (ocp != NULL)
                        *ocp = '-';
                *vname = cp + 1;
                *cp = '\0';
                ocp = cp;
                if (efi_name_to_guid(name, guid) >= 0)
                        break;
        }
}

static uint8_t *
get_value(char *val, size_t *datalen)
{
        static char buffer[16*1024];

        if (val != NULL) {
                *datalen = strlen(val);
                return ((uint8_t *)val);
        }
        /* Read from stdin */
        *datalen = sizeof(buffer);
        *datalen = read(0, buffer, *datalen);
        return ((uint8_t *)buffer);
}

static void
append_variable(char *name, char *val)
{
        char *vname;
        efi_guid_t guid;
        size_t datalen;
        uint8_t *data;

        breakdown_name(name, &guid, &vname);
        data = get_value(val, &datalen);
        if (efi_append_variable(guid, vname, data, datalen, attrib) < 0)
                rep_err(1, "efi_append_variable");
}

static void
delete_variable(char *name)
{
        char *vname;
        efi_guid_t guid;

        breakdown_name(name, &guid, &vname);
        if (efi_del_variable(guid, vname) < 0)
                rep_err(1, "efi_del_variable");
}

static void
write_variable(char *name, char *val)
{
        char *vname;
        efi_guid_t guid;
        size_t datalen;
        uint8_t *data;

        breakdown_name(name, &guid, &vname);
        data = get_value(val, &datalen);
        if (efi_set_variable(guid, vname, data, datalen, attrib) < 0)
                rep_err(1, "efi_set_variable");
}

static void
devpath_dump(uint8_t *data, size_t datalen)
{
        char buffer[1024];

        efidp_format_device_path(buffer, sizeof(buffer),
            (const_efidp)data, datalen);
        if (!Nflag)
                printf(": ");
        printf("%s\n", buffer);
}

static void
pretty_guid(efi_guid_t *guid, char **gname)
{
        char *pretty = NULL;

        if (gflag)
                efi_guid_to_name(guid, &pretty);

        if (pretty == NULL)
                efi_guid_to_str(guid, gname);
        else
                *gname = pretty;
}

static void
print_var(efi_guid_t *guid, char *name)
{
        uint32_t att;
        uint8_t *data;
        size_t datalen;
        char *gname = NULL;
        int rv;

        if (guid)
                pretty_guid(guid, &gname);
        if (pflag || fromfile) {
                if (fromfile) {
                        int fd;

                        fd = open(fromfile, O_RDONLY);
                        if (fd < 0)
                                rep_err(1, "open %s", fromfile);
                        data = malloc(64 * 1024);
                        if (data == NULL)
                                rep_err(1, "malloc");
                        datalen = read(fd, data, 64 * 1024);
                        if ((ssize_t)datalen < 0)
                                rep_err(1, "read");
                        if (datalen == 0)
                                rep_errx(1, "empty file");
                        close(fd);
                } else {
                        rv = efi_get_variable(*guid, name, &data, &datalen, &att);
                        if (rv < 0)
                                rep_err(1, "fetching %s-%s", gname, name);
                }


                if (!Nflag)
                        printf("%s-%s\n", gname, name);
                if (load_opt_flag)
                        efi_print_load_option(data, datalen, Aflag, bflag, uflag);
                else if (Aflag)
                        asciidump(data, datalen);
                else if (uflag)
                        utf8dump(data, datalen);
                else if (bflag)
                        bindump(data, datalen);
                else if (dflag)
                        devpath_dump(data, datalen);
                else
                        hexdump(data, datalen);
        } else {
                printf("%s-%s", gname, name);
        }
        free(gname);
        if (!Nflag)
                printf("\n");
}

static void
print_variable(char *name)
{
        char *vname;
        efi_guid_t guid;

        breakdown_name(name, &guid, &vname);
        print_var(&guid, vname);
}

static void
print_variables(void)
{
        int rv;
        char *name = NULL;
        efi_guid_t *guid = NULL;

        while ((rv = efi_get_next_variable_name(&guid, &name)) > 0)
                print_var(guid, name);

        if (rv < 0)
                rep_err(1, "Error listing names");
}

static void
print_known_guid(void)
{
        struct guid_table *tbl;
        int i, n;

        n = efi_known_guid(&tbl);
        for (i = 0; i < n; i++)
                printf("%s %s\n", tbl[i].uuid_str, tbl[i].name);
}

static void
parse_args(int argc, char **argv)
{
        int ch, i;

        while ((ch = getopt_long(argc, argv, "aAbdDf:gHlLNn:OpqRt:uw",
                    longopts, NULL)) != -1) {
                switch (ch) {
                case 'a':
                        aflag = true;
                        break;
                case 'A':
                        Aflag = true;
                        break;
                case 'b':
                        bflag = true;
                        break;
                case 'd':
                        dflag = true;
                        break;
                case 'D':
                        Dflag = true;
                        break;
                case 'g':
                        gflag = true;
                        break;
                case 'H':
                        Hflag = true;
                        break;
                case 'l':
                        lflag = true;
                        break;
                case 'L':
                        Lflag = true;
                        break;
                case 'n':
                        varname = optarg;
                        break;
                case 'N':
                        Nflag = true;
                        break;
                case 'O':
                        load_opt_flag = true;
                        break;
                case 'p':
                        pflag = true;
                        break;
                case 'q':
                        quiet = true;
                        break;
                case 'R':
                        Rflag = true;
                        break;
                case 't':
                        attrib = strtoul(optarg, NULL, 16);
                        break;
                case 'u':
                        uflag = true;
                        break;
                case 'w':
                        wflag = true;
                        break;
                case 'f':
                        free(fromfile);
                        fromfile = strdup(optarg);
                        break;
                case 0:
                        rep_errx(1, "unknown or unimplemented option\n");
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;

        if (argc == 1)
                varname = argv[0];

        if ((int)aflag + (int)Dflag + (int)wflag > 1) {
                warnx("Can only use one of -a (--append), "
                    "-D (--delete) and -w (--write)");
                usage();
        }

        if ((int)aflag + (int)Dflag + (int)wflag > 0 && varname == NULL) {
                warnx("Must specify a variable for -a (--append), "
                    "-D (--delete) or -w (--write)");
                usage();
        }

        if (aflag)
                append_variable(varname, NULL);
        else if (Dflag)
                delete_variable(varname);
        else if (wflag)
                write_variable(varname, NULL);
        else if (Lflag)
                print_known_guid();
        else if (fromfile) {
                Nflag = true;
                print_var(NULL, NULL);
        } else if (varname) {
                pflag = true;
                print_variable(varname);
        } else if (argc > 0) {
                pflag = true;
                for (i = 0; i < argc; i++)
                        print_variable(argv[i]);
        } else
                print_variables();
}

int
main(int argc, char **argv)
{

        parse_args(argc, argv);
}