static struct timeval start_time;
static int ticks_per_sec;
static int exec_seen;
+static int partial_line;
#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ > 0
/* glibc 2.1 or newer -> has lseek64 */
exit(1);
}
+static void
+flush_line(void)
+{
+ if (partial_line)
+ fputc('\n', stderr);
+ partial_line = 0;
+}
+
static void NONRET __attribute__((format(printf,1,2)))
die(char *msg, ...)
{
va_list args;
va_start(args, msg);
+ flush_line();
vfprintf(stderr, msg, args);
fputc('\n', stderr);
box_exit();
va_start(args, msg);
if (verbose)
{
+ int len = strlen(msg);
+ if (len > 0)
+ partial_line = (msg[len-1] != '\n');
vfprintf(stderr, msg, args);
fflush(stderr);
}
return p;
}
+/*** Syscall rules ***/
+
static const char * const syscall_names[] = {
#include "syscall-table.h"
};
enum action {
A_DEFAULT, // Use the default action
- A_NO, // Always forbid
+ A_NO, // Always forbid
A_YES, // Always permit
A_FILENAME, // Permit if arg1 is a known filename
A_LIBERAL = 128, // Valid only in liberal mode
return 1;
}
+/*** Path rules ***/
+
struct path_rule {
char *path;
enum action action;
return 0;
}
- struct path_rule *r = xmalloc(sizeof(*r) + strlen(a));
+ struct path_rule *r = xmalloc(sizeof(*r) + strlen(a) + 1);
r->path = (char *)(r+1);
strcpy(r->path, a);
r->action = act;
return r->action;
}
+/*** Environment rules ***/
+
+struct env_rule {
+ char *var; // Variable to match
+ char *val; // ""=clear, NULL=inherit
+ int var_len;
+ struct env_rule *next;
+};
+
+static struct env_rule *first_env_rule;
+static struct env_rule **last_env_rule = &first_env_rule;
+
+static struct env_rule default_env_rules[] = {
+ { "LIBC_FATAL_STDERR_", "1" }
+};
+
+static int
+set_env_action(char *a0)
+{
+ struct env_rule *r = xmalloc(sizeof(*r) + strlen(a0) + 1);
+ char *a = (char *)(r+1);
+ strcpy(a, a0);
+
+ char *sep = strchr(a, '=');
+ if (sep == a)
+ return 0;
+ r->var = a;
+ if (sep)
+ {
+ *sep++ = 0;
+ r->val = sep;
+ }
+ else
+ r->val = NULL;
+ *last_env_rule = r;
+ last_env_rule = &r->next;
+ r->next = NULL;
+ return 1;
+}
+
+static int
+match_env_var(char *env_entry, struct env_rule *r)
+{
+ if (strncmp(env_entry, r->var, r->var_len))
+ return 0;
+ return (env_entry[r->var_len] == '=');
+}
+
+static void
+apply_env_rule(char **env, int *env_sizep, struct env_rule *r)
+{
+ // First remove the variable if already set
+ int pos = 0;
+ while (pos < *env_sizep && !match_env_var(env[pos], r))
+ pos++;
+ if (pos < *env_sizep)
+ {
+ (*env_sizep)--;
+ env[pos] = env[*env_sizep];
+ env[*env_sizep] = NULL;
+ }
+
+ // What is the new value?
+ char *new;
+ if (r->val)
+ {
+ if (!r->val[0])
+ return;
+ new = xmalloc(r->var_len + 1 + strlen(r->val) + 1);
+ sprintf(new, "%s=%s", r->var, r->val);
+ }
+ else
+ {
+ pos = 0;
+ while (environ[pos] && !match_env_var(environ[pos], r))
+ pos++;
+ if (!(new = environ[pos]))
+ return;
+ }
+
+ // Add it at the end of the array
+ env[(*env_sizep)++] = new;
+ env[*env_sizep] = NULL;
+}
+
+static char **
+setup_environment(void)
+{
+ // Link built-in rules with user rules
+ for (int i=ARRAY_SIZE(default_env_rules)-1; i >= 0; i--)
+ {
+ default_env_rules[i].next = first_env_rule;
+ first_env_rule = &default_env_rules[i];
+ }
+
+ // Scan the original environment
+ char **orig_env = environ;
+ int orig_size = 0;
+ while (orig_env[orig_size])
+ orig_size++;
+
+ // For each rule, reserve one more slot and calculate length
+ int num_rules = 0;
+ for (struct env_rule *r = first_env_rule; r; r=r->next)
+ {
+ num_rules++;
+ r->var_len = strlen(r->var);
+ }
+
+ // Create a new environment
+ char **env = xmalloc((orig_size + num_rules + 1) * sizeof(char *));
+ int size;
+ if (pass_environ)
+ {
+ memcpy(env, environ, orig_size * sizeof(char *));
+ size = orig_size;
+ }
+ else
+ size = 0;
+ env[size] = NULL;
+
+ // Apply the rules one by one
+ for (struct env_rule *r = first_env_rule; r; r=r->next)
+ apply_env_rule(env, &size, r);
+
+ // Return the new env and pass some gossip
+ if (verbose > 1)
+ {
+ fprintf(stderr, "Passing environment:\n");
+ for (int i=0; env[i]; i++)
+ fprintf(stderr, "\t%s\n", env[i]);
+ }
+ return env;
+}
+
+/*** Syscall checks ***/
+
static void
valid_filename(unsigned long addr)
{
die("Time limit exceeded");
if (wall_timeout && wall_ms > wall_timeout)
die("Time limit exceeded (wall clock)");
+ flush_line();
fprintf(stderr, "OK (%d.%03d sec real, %d.%03d sec wall, %d syscalls)\n",
(int) total.tv_sec, (int) total.tv_usec/1000,
(int) wall.tv_sec, (int) wall.tv_usec/1000,
{
struct rlimit rl;
char *args[argc+1];
- char *env[] = { "LIBC_FATAL_STDERR_=1", NULL };
memcpy(args, argv, argc * sizeof(char *));
args[argc] = NULL;
signal(SIGCHLD, SIG_IGN);
raise(SIGCHLD);
}
- execve(args[0], args, (pass_environ ? environ : env));
+ execve(args[0], args, setup_environment());
die("execve(\"%s\"): %m", args[0]);
}
Options:\n\
-a <level>\tSet file access level (0=none, 1=cwd, 2=/etc,/lib,..., 3=whole fs, 9=no checks; needs -f)\n\
-c <dir>\tChange directory to <dir> first\n\
--e\t\tPass full environment of parent process\n\
+-e\t\tInherit full environment of the parent process\n\
+-E <var>\tInherit the environment variable <var> from the parent process\n\
+-E <var>=<val>\tSet the environment variable <var> to <val>; unset it if <var> is empty\n\
-f\t\tFilter system calls (-ff=very restricted)\n\
-i <file>\tRedirect stdin from <file>\n\
-m <size>\tLimit address space to <size> KB\n\
-s <sys>=<act>\tDefine action for the specified syscall (<act>=yes/no/file)\n\
-t <time>\tSet run time limit (seconds, fractions allowed)\n\
-T\t\tAllow syscalls for measuring run time\n\
--v\t\tBe verbose\n\
+-v\t\tBe verbose (use multiple times for even more verbosity)\n\
-w <time>\tSet wall clock time limit (seconds, fractions allowed)\n\
");
exit(1);
int c;
uid_t uid;
- while ((c = getopt(argc, argv, "a:c:efi:m:o:p:s:t:Tvw:")) >= 0)
+ while ((c = getopt(argc, argv, "a:c:eE:fi:m:o:p:s:t:Tvw:")) >= 0)
switch (c)
{
case 'a':
case 'e':
pass_environ = 1;
break;
+ case 'E':
+ if (!set_env_action(optarg))
+ usage();
+ break;
case 'f':
filter_syscalls++;
break;
projects / moe.git / blobdiff