tools/verification/rv/src/rv.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * rv tool, the interface for the Linux kernel RV subsystem and home of
   4  * user-space controlled monitors.
   5  *
   6  * Copyright (C) 2022 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org>
   7  */
   8
   9 #include <stdlib.h>
  10 #include <signal.h>
  11 #include <unistd.h>
  12
  13 #include <trace.h>
  14 #include <utils.h>
  15 #include <in_kernel.h>
  16
  17 static int stop_session;
  18
  19 /*
  20  * stop_rv - tell monitors to stop
  21  */
  22 static void stop_rv(int sig)
  23 {
  24         stop_session = 1;
  25 }
  26
  27 /**
  28  * should_stop - check if the monitor should stop.
  29  *
  30  * Returns 1 if the monitor should stop, 0 otherwise.
  31  */
  32 int should_stop(void)
  33 {
  34         return stop_session;
  35 }
  36
  37 /*
  38  * rv_list - list all available monitors
  39  */
  40 static void rv_list(int argc, char **argv)
  41 {
  42         static const char *const usage[] = {
  43                 "",
  44                 "  usage: rv list [-h]",
  45                 "",
  46                 "       list all available monitors",
  47                 "",
  48                 "       -h/--help: print this menu",
  49                 NULL,
  50         };
  51         int i;
  52
  53         if (argc > 1) {
  54                 fprintf(stderr, "rv version %s\n", VERSION);
  55
  56                 /* more than 1 is always usage */
  57                 for (i = 0; usage[i]; i++)
  58                         fprintf(stderr, "%s\n", usage[i]);
  59
  60                 /* but only -h is valid */
  61                 if (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help"))
  62                         exit(0);
  63                 else
  64                         exit(1);
  65         }
  66
  67         ikm_list_monitors();
  68         exit(0);
  69 }
  70
  71 /*
  72  * rv_mon - try to run a monitor passed as argument
  73  */
  74 static void rv_mon(int argc, char **argv)
  75 {
  76         char *monitor_name;
  77         int i, run = 0;
  78
  79         static const char *const usage[] = {
  80                 "",
  81                 "  usage: rv mon [-h] monitor [monitor options]",
  82                 "",
  83                 "       run a monitor",
  84                 "",
  85                 "       -h/--help: print this menu",
  86                 "",
  87                 "       monitor [monitor options]: the monitor, passing",
  88                 "       the arguments to the [monitor options]",
  89                 NULL,
  90         };
  91
  92         /* requires at least one argument */
  93         if (argc == 1) {
  94
  95                 fprintf(stderr, "rv version %s\n", VERSION);
  96
  97                 for (i = 0; usage[i]; i++)
  98                         fprintf(stderr, "%s\n", usage[i]);
  99                 exit(1);
 100         } else if (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help")) {
 101
 102                 fprintf(stderr, "rv version %s\n", VERSION);
 103
 104                 for (i = 0; usage[i]; i++)
 105                         fprintf(stderr, "%s\n", usage[i]);
 106                 exit(0);
 107         }
 108
 109         monitor_name = argv[1];
 110         /*
 111          * Call all possible monitor implementations, looking
 112          * for the [monitor].
 113          */
 114         run += ikm_run_monitor(monitor_name, argc-1, &argv[1]);
 115
 116         if (!run)
 117                 err_msg("rv: monitor %s does not exist\n", monitor_name);
 118         exit(!run);
 119 }
 120
 121 static void usage(int exit_val, const char *fmt, ...)
 122 {
 123         char message[1024];
 124         va_list ap;
 125         int i;
 126
 127         static const char *const usage[] = {
 128                 "",
 129                 "  usage: rv command [-h] [command_options]",
 130                 "",
 131                 "       -h/--help: print this menu",
 132                 "",
 133                 "       command: run one of the following command:",
 134                 "         list: list all available monitors",
 135                 "         mon:  run a monitor",
 136                 "",
 137                 "       [command options]: each command has its own set of options",
 138                 "                          run rv command -h for further information",
 139                 NULL,
 140         };
 141
 142         va_start(ap, fmt);
 143         vsnprintf(message, sizeof(message), fmt, ap);
 144         va_end(ap);
 145
 146         fprintf(stderr, "rv version %s: %s\n", VERSION, message);
 147
 148         for (i = 0; usage[i]; i++)
 149                 fprintf(stderr, "%s\n", usage[i]);
 150
 151         exit(exit_val);
 152 }
 153
 154 /*
 155  * main - select which main sending the command
 156  *
 157  * main itself redirects the arguments to the sub-commands
 158  * to handle the options.
 159  *
 160  * subcommands should exit.
 161  */
 162 int main(int argc, char **argv)
 163 {
 164         if (geteuid())
 165                 usage(1, "%s needs root permission", argv[0]);
 166
 167         if (argc <= 1)
 168                 usage(1, "%s requires a command", argv[0]);
 169
 170         if (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help"))
 171                 usage(0, "help");
 172
 173         if (!strcmp(argv[1], "list"))
 174                 rv_list(--argc, &argv[1]);
 175
 176         if (!strcmp(argv[1], "mon")) {
 177                 /*
 178                  * monitor's main should monitor should_stop() function.
 179                  * and exit.
 180                  */
 181                 signal(SIGINT, stop_rv);
 182
 183                 rv_mon(argc - 1, &argv[1]);
 184         }
 185
 186         /* invalid sub-command */
 187         usage(1, "%s does not know the %s command, old version?", argv[0], argv[1]);
 188 }