va_end(args);
}
-static const char * const syscall_tab[] = {
+static void *
+xmalloc(size_t size)
+{
+ void *p = malloc(size);
+ if (!p)
+ die("Out of memory");
+ return p;
+}
+
+static const char * const syscall_names[] = {
#include "syscall-table.h"
};
-#define NUM_SYSCALLS (sizeof(syscall_tab)/sizeof(syscall_tab[0]))
+#define NUM_SYSCALLS ARRAY_SIZE(syscall_names)
#define NUM_ACTIONS (NUM_SYSCALLS+64)
enum action {
- SC_DEFAULT, // Use the default action
- SC_NO, // Always forbid
- SC_YES, // Always permit
- SC_FILENAME, // Permit if arg1 is a known filename
- SC_LIBERAL = 128, // Valid only in liberal mode
+ A_DEFAULT, // Use the default action
+ 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
};
static unsigned char syscall_action[NUM_ACTIONS] = {
#define S(x) [__NR_##x]
// Syscalls permitted for specific file names
- S(open) = SC_FILENAME,
- S(creat) = SC_FILENAME,
- S(unlink) = SC_FILENAME,
- S(oldstat) = SC_FILENAME,
- S(access) = SC_FILENAME,
- S(oldlstat) = SC_FILENAME,
- S(truncate) = SC_FILENAME,
- S(stat) = SC_FILENAME,
- S(lstat) = SC_FILENAME,
- S(truncate64) = SC_FILENAME,
- S(stat64) = SC_FILENAME,
- S(lstat64) = SC_FILENAME,
- S(readlink) = SC_FILENAME,
+ S(open) = A_FILENAME,
+ S(creat) = A_FILENAME,
+ S(unlink) = A_FILENAME,
+ S(oldstat) = A_FILENAME,
+ S(access) = A_FILENAME,
+ S(oldlstat) = A_FILENAME,
+ S(truncate) = A_FILENAME,
+ S(stat) = A_FILENAME,
+ S(lstat) = A_FILENAME,
+ S(truncate64) = A_FILENAME,
+ S(stat64) = A_FILENAME,
+ S(lstat64) = A_FILENAME,
+ S(readlink) = A_FILENAME,
// Syscalls permitted always
- S(exit) = SC_YES,
- S(read) = SC_YES,
- S(write) = SC_YES,
- S(close) = SC_YES,
- S(lseek) = SC_YES,
- S(getpid) = SC_YES,
- S(getuid) = SC_YES,
- S(oldfstat) = SC_YES,
- S(dup) = SC_YES,
- S(brk) = SC_YES,
- S(getgid) = SC_YES,
- S(geteuid) = SC_YES,
- S(getegid) = SC_YES,
- S(dup2) = SC_YES,
- S(ftruncate) = SC_YES,
- S(fstat) = SC_YES,
- S(personality) = SC_YES,
- S(_llseek) = SC_YES,
- S(readv) = SC_YES,
- S(writev) = SC_YES,
- S(getresuid) = SC_YES,
+ S(exit) = A_YES,
+ S(read) = A_YES,
+ S(write) = A_YES,
+ S(close) = A_YES,
+ S(lseek) = A_YES,
+ S(getpid) = A_YES,
+ S(getuid) = A_YES,
+ S(oldfstat) = A_YES,
+ S(dup) = A_YES,
+ S(brk) = A_YES,
+ S(getgid) = A_YES,
+ S(geteuid) = A_YES,
+ S(getegid) = A_YES,
+ S(dup2) = A_YES,
+ S(ftruncate) = A_YES,
+ S(fstat) = A_YES,
+ S(personality) = A_YES,
+ S(_llseek) = A_YES,
+ S(readv) = A_YES,
+ S(writev) = A_YES,
+ S(getresuid) = A_YES,
#ifdef __NR_pread64
- S(pread64) = SC_YES,
- S(pwrite64) = SC_YES,
+ S(pread64) = A_YES,
+ S(pwrite64) = A_YES,
#else
- S(pread) = SC_YES,
- S(pwrite) = SC_YES,
+ S(pread) = A_YES,
+ S(pwrite) = A_YES,
#endif
- S(ftruncate64) = SC_YES,
- S(fstat64) = SC_YES,
- S(fcntl) = SC_YES,
- S(fcntl64) = SC_YES,
- S(mmap) = SC_YES,
- S(munmap) = SC_YES,
- S(ioctl) = SC_YES,
- S(uname) = SC_YES,
- S(gettid) = SC_YES,
- S(set_thread_area) = SC_YES,
- S(get_thread_area) = SC_YES,
- S(exit_group) = SC_YES,
+ S(ftruncate64) = A_YES,
+ S(fstat64) = A_YES,
+ S(fcntl) = A_YES,
+ S(fcntl64) = A_YES,
+ S(mmap) = A_YES,
+ S(munmap) = A_YES,
+ S(ioctl) = A_YES,
+ S(uname) = A_YES,
+ S(gettid) = A_YES,
+ S(set_thread_area) = A_YES,
+ S(get_thread_area) = A_YES,
+ S(exit_group) = A_YES,
// Syscalls permitted only in liberal mode
- S(time) = SC_YES | SC_LIBERAL,
- S(alarm) = SC_YES | SC_LIBERAL,
- S(pause) = SC_YES | SC_LIBERAL,
- S(signal) = SC_YES | SC_LIBERAL,
- S(fchmod) = SC_YES | SC_LIBERAL,
- S(sigaction) = SC_YES | SC_LIBERAL,
- S(sgetmask) = SC_YES | SC_LIBERAL,
- S(ssetmask) = SC_YES | SC_LIBERAL,
- S(sigsuspend) = SC_YES | SC_LIBERAL,
- S(sigpending) = SC_YES | SC_LIBERAL,
- S(getrlimit) = SC_YES | SC_LIBERAL,
- S(getrusage) = SC_YES | SC_LIBERAL,
- S(ugetrlimit) = SC_YES | SC_LIBERAL,
- S(gettimeofday) = SC_YES | SC_LIBERAL,
- S(select) = SC_YES | SC_LIBERAL,
- S(readdir) = SC_YES | SC_LIBERAL,
- S(setitimer) = SC_YES | SC_LIBERAL,
- S(getitimer) = SC_YES | SC_LIBERAL,
- S(sigreturn) = SC_YES | SC_LIBERAL,
- S(mprotect) = SC_YES | SC_LIBERAL,
- S(sigprocmask) = SC_YES | SC_LIBERAL,
- S(getdents) = SC_YES | SC_LIBERAL,
- S(getdents64) = SC_YES | SC_LIBERAL,
- S(_newselect) = SC_YES | SC_LIBERAL,
- S(fdatasync) = SC_YES | SC_LIBERAL,
- S(mremap) = SC_YES | SC_LIBERAL,
- S(poll) = SC_YES | SC_LIBERAL,
- S(getcwd) = SC_YES | SC_LIBERAL,
- S(nanosleep) = SC_YES | SC_LIBERAL,
- S(rt_sigreturn) = SC_YES | SC_LIBERAL,
- S(rt_sigaction) = SC_YES | SC_LIBERAL,
- S(rt_sigprocmask) = SC_YES | SC_LIBERAL,
- S(rt_sigpending) = SC_YES | SC_LIBERAL,
- S(rt_sigtimedwait) = SC_YES | SC_LIBERAL,
- S(rt_sigqueueinfo) = SC_YES | SC_LIBERAL,
- S(rt_sigsuspend) = SC_YES | SC_LIBERAL,
- S(mmap2) = SC_YES | SC_LIBERAL,
- S(_sysctl) = SC_YES | SC_LIBERAL,
+ S(time) = A_YES | A_LIBERAL,
+ S(alarm) = A_YES | A_LIBERAL,
+ S(pause) = A_YES | A_LIBERAL,
+ S(signal) = A_YES | A_LIBERAL,
+ S(fchmod) = A_YES | A_LIBERAL,
+ S(sigaction) = A_YES | A_LIBERAL,
+ S(sgetmask) = A_YES | A_LIBERAL,
+ S(ssetmask) = A_YES | A_LIBERAL,
+ S(sigsuspend) = A_YES | A_LIBERAL,
+ S(sigpending) = A_YES | A_LIBERAL,
+ S(getrlimit) = A_YES | A_LIBERAL,
+ S(getrusage) = A_YES | A_LIBERAL,
+ S(ugetrlimit) = A_YES | A_LIBERAL,
+ S(gettimeofday) = A_YES | A_LIBERAL,
+ S(select) = A_YES | A_LIBERAL,
+ S(readdir) = A_YES | A_LIBERAL,
+ S(setitimer) = A_YES | A_LIBERAL,
+ S(getitimer) = A_YES | A_LIBERAL,
+ S(sigreturn) = A_YES | A_LIBERAL,
+ S(mprotect) = A_YES | A_LIBERAL,
+ S(sigprocmask) = A_YES | A_LIBERAL,
+ S(getdents) = A_YES | A_LIBERAL,
+ S(getdents64) = A_YES | A_LIBERAL,
+ S(_newselect) = A_YES | A_LIBERAL,
+ S(fdatasync) = A_YES | A_LIBERAL,
+ S(mremap) = A_YES | A_LIBERAL,
+ S(poll) = A_YES | A_LIBERAL,
+ S(getcwd) = A_YES | A_LIBERAL,
+ S(nanosleep) = A_YES | A_LIBERAL,
+ S(rt_sigreturn) = A_YES | A_LIBERAL,
+ S(rt_sigaction) = A_YES | A_LIBERAL,
+ S(rt_sigprocmask) = A_YES | A_LIBERAL,
+ S(rt_sigpending) = A_YES | A_LIBERAL,
+ S(rt_sigtimedwait) = A_YES | A_LIBERAL,
+ S(rt_sigqueueinfo) = A_YES | A_LIBERAL,
+ S(rt_sigsuspend) = A_YES | A_LIBERAL,
+ S(mmap2) = A_YES | A_LIBERAL,
+ S(_sysctl) = A_YES | A_LIBERAL,
#undef S
};
static const char *
syscall_name(unsigned int id, char *buf)
{
- if (id < NUM_SYSCALLS && syscall_tab[id])
- return syscall_tab[id];
+ if (id < NUM_SYSCALLS && syscall_names[id])
+ return syscall_names[id];
else
{
sprintf(buf, "#%d", id);
static int
syscall_by_name(char *name)
{
- for (unsigned int i=0; i<sizeof(syscall_tab)/sizeof(syscall_tab[0]); i++)
- if (syscall_tab[i] && !strcmp(syscall_tab[i], name))
+ for (unsigned int i=0; i<NUM_SYSCALLS; i++)
+ if (syscall_names[i] && !strcmp(syscall_names[i], name))
return i;
if (name[0] == '#')
name++;
}
static int
-set_action(char *a)
+set_syscall_action(char *a)
{
char *sep = strchr(a, '=');
- enum action act = SC_YES;
+ enum action act = A_YES;
if (sep)
{
*sep++ = 0;
if (!strcmp(sep, "yes"))
- act = SC_YES;
+ act = A_YES;
else if (!strcmp(sep, "no"))
- act = SC_NO;
+ act = A_NO;
else if (!strcmp(sep, "file"))
- act = SC_FILENAME;
+ act = A_FILENAME;
else
return 0;
}
int sys = syscall_by_name(a);
if (sys < 0)
die("Unknown syscall `%s'", a);
- if (sys >= (int)NUM_ACTIONS)
+ if (sys >= NUM_ACTIONS)
die("Syscall `%s' out of range", a);
syscall_action[sys] = act;
return 1;
};
static struct path_rule default_path_rules[] = {
- { "/etc/", SC_YES },
- { "/lib/", SC_YES },
- { "/usr/lib/", SC_YES },
- { "/opt/lib/", SC_YES },
- { "/usr/share/zoneinfo/", SC_YES },
- { "/usr/share/locale/", SC_YES },
- { "/dev/null", SC_YES },
- { "/dev/zero", SC_YES },
- { "/proc/meminfo", SC_YES },
- { "/proc/self/stat", SC_YES },
- { "/proc/self/exe", SC_YES }, // Needed by FPC 2.0.x runtime
+ { "/etc/", A_YES },
+ { "/lib/", A_YES },
+ { "/usr/lib/", A_YES },
+ { "/opt/lib/", A_YES },
+ { "/usr/share/zoneinfo/", A_YES },
+ { "/usr/share/locale/", A_YES },
+ { "/dev/null", A_YES },
+ { "/dev/zero", A_YES },
+ { "/proc/meminfo", A_YES },
+ { "/proc/self/stat", A_YES },
+ { "/proc/self/exe", A_YES }, // Needed by FPC 2.0.x runtime
};
+static struct path_rule *user_path_rules;
+static struct path_rule **last_path_rule = &user_path_rules;
+
+static int
+set_path_action(char *a)
+{
+ char *sep = strchr(a, '=');
+ enum action act = A_YES;
+ if (sep)
+ {
+ *sep++ = 0;
+ if (!strcmp(sep, "yes"))
+ act = A_YES;
+ else if (!strcmp(sep, "no"))
+ act = A_NO;
+ else
+ return 0;
+ }
+
+ struct path_rule *r = xmalloc(sizeof(*r) + strlen(a));
+ r->path = (char *)(r+1);
+ strcpy(r->path, a);
+ r->action = act;
+ r->next = NULL;
+ *last_path_rule = r;
+ last_path_rule = &r->next;
+ return 1;
+}
+
static enum action
match_path_rule(struct path_rule *r, char *path)
{
{
if (rr[-1] == '/' && !path[-1])
break;
- return SC_DEFAULT;
+ return A_DEFAULT;
}
if (rr > r->path && rr[-1] != '/' && *path)
- return SC_DEFAULT;
+ return A_DEFAULT;
return r->action;
}
return;
// ".." anywhere in the path is forbidden
- enum action act = SC_DEFAULT;
+ enum action act = A_DEFAULT;
if (strstr(namebuf, ".."))
- act = SC_NO;
+ act = A_NO;
+
+ // Scan user rules
+ for (struct path_rule *r = user_path_rules; r && !act; r=r->next)
+ act = match_path_rule(r, namebuf);
// Scan built-in rules
if (file_access >= 2)
for (int i=0; i<ARRAY_SIZE(default_path_rules) && !act; i++)
act = match_path_rule(&default_path_rules[i], namebuf);
- if (act != SC_YES)
+ if (act != A_YES)
die("Forbidden access to file `%s'", namebuf);
}
valid_syscall(struct user *u)
{
unsigned int sys = u->regs.orig_eax;
- enum action act = (sys < NUM_ACTIONS) ? syscall_action[sys] : SC_DEFAULT;
+ enum action act = (sys < NUM_ACTIONS) ? syscall_action[sys] : A_DEFAULT;
- if (act & SC_LIBERAL)
+ if (act & A_LIBERAL)
{
if (filter_syscalls == 1)
- act &= ~SC_LIBERAL;
+ act &= ~A_LIBERAL;
else
- act = SC_DEFAULT;
+ act = A_DEFAULT;
}
switch (act)
{
- case SC_YES:
+ case A_YES:
return 1;
- case SC_NO:
+ case A_NO:
return 0;
- case SC_FILENAME:
+ case A_FILENAME:
valid_filename(u->regs.ebx);
return 1;
default: ;
-i <file>\tRedirect stdin from <file>\n\
-m <size>\tLimit address space to <size> KB\n\
-o <file>\tRedirect stdout to <file>\n\
+-p <path>\tPermit access to the specified path (or subtree if it ends with a `/')\n\
+-p <path>=<act>\tDefine action for the specified path (<act>=yes/no)\n\
-s <sys>\tPermit the specified syscall (be careful)\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\
int c;
uid_t uid;
- while ((c = getopt(argc, argv, "a:c:efi:m:o:s:t:Tvw:")) >= 0)
+ while ((c = getopt(argc, argv, "a:c:efi:m:o:p:s:t:Tvw:")) >= 0)
switch (c)
{
case 'a':
case 'o':
redir_stdout = optarg;
break;
+ case 'p':
+ if (!set_path_action(optarg))
+ usage();
+ break;
case 's':
- if (!set_action(optarg))
+ if (!set_syscall_action(optarg))
usage();
break;
case 't':
timeout = 1000*atof(optarg);
break;
case 'T':
- syscall_action[__NR_times] = SC_YES;
+ syscall_action[__NR_times] = A_YES;
break;
case 'v':
verbose++;
projects / eval.git / blobdiff