-/* $OpenBSD: doas.c,v 1.7 2015/07/18 00:19:38 doug Exp $ */
+/* $OpenBSD: doas.c,v 1.19 2015/07/22 05:37:23 deraadt Exp $ */
/*
* Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
*
#include <pwd.h>
#include <grp.h>
#include <syslog.h>
+#include <errno.h>
#include "doas.h"
static void __dead
usage(void)
{
- fprintf(stderr, "usage: doas [-s] [-u user] command [args]\n");
+ fprintf(stderr, "usage: doas [-s] [-C config] [-u user] command [args]\n");
exit(1);
}
arraylen(const char **arr)
{
size_t cnt = 0;
+
while (*arr) {
cnt++;
arr++;
static int
match(uid_t uid, gid_t *groups, int ngroups, uid_t target, const char *cmd,
- struct rule *r)
+ const char **cmdargs, struct rule *r)
{
int i;
}
if (r->target && uidcheck(r->target, target) != 0)
return 0;
- if (r->cmd && strcmp(r->cmd, cmd) != 0)
- return 0;
+ if (r->cmd) {
+ if (strcmp(r->cmd, cmd))
+ return 0;
+ if (r->cmdargs) {
+ /* if arguments were given, they should match explicitly */
+ for (i = 0; r->cmdargs[i]; i++) {
+ if (!cmdargs[i])
+ return 0;
+ if (strcmp(r->cmdargs[i], cmdargs[i]))
+ return 0;
+ }
+ if (cmdargs[i])
+ return 0;
+ }
+ }
return 1;
}
static int
permit(uid_t uid, gid_t *groups, int ngroups, struct rule **lastr,
- uid_t target, const char *cmd)
+ uid_t target, const char *cmd, const char **cmdargs)
{
int i;
*lastr = NULL;
for (i = 0; i < nrules; i++) {
- if (match(uid, groups, ngroups, target, cmd, rules[i]))
+ if (match(uid, groups, ngroups, target, cmd, cmdargs, rules[i]))
*lastr = rules[i];
}
if (!*lastr)
char **envp, int ei)
{
int i;
+
for (i = 0; i < nsafe; i++) {
const char **oe = oldenvp;
while (*oe) {
copyenv(const char **oldenvp, struct rule *rule)
{
const char *safeset[] = {
- "DISPLAY", "HOME", "LOGNAME", "MAIL", "SHELL",
+ "DISPLAY", "HOME", "LOGNAME", "MAIL",
"PATH", "TERM", "USER", "USERNAME",
- NULL,
+ NULL
+ };
+ const char *badset[] = {
+ "ENV",
+ NULL
};
- int nsafe;
- int nextras = 0;
char **envp;
const char **extra;
int ei;
- int i, j;
-
+ int nsafe, nbad;
+ int nextras = 0;
+
+ nbad = arraylen(badset);
if ((rule->options & KEEPENV) && !rule->envlist) {
- j = arraylen(oldenvp);
- envp = reallocarray(NULL, j + 1, sizeof(char *));
+ size_t i, ii;
+ size_t oldlen = arraylen(oldenvp);
+ envp = reallocarray(NULL, oldlen + 1, sizeof(char *));
if (!envp)
err(1, "reallocarray");
- for (i = 0; i < j; i++) {
- if (!(envp[i] = strdup(oldenvp[i])))
- err(1, "strdup");
+ for (ii = i = 0; i < oldlen; i++) {
+ size_t j;
+ for (j = 0; j < nbad; j++) {
+ size_t len = strlen(badset[j]);
+ if (strncmp(oldenvp[i], badset[j], len) == 0 &&
+ oldenvp[i][len] == '=') {
+ break;
+ }
+ }
+ if (j == nbad) {
+ if (!(envp[ii] = strdup(oldenvp[i])))
+ err(1, "strdup");
+ ii++;
+ }
}
- envp[i] = NULL;
+ envp[ii] = NULL;
return envp;
}
nsafe = arraylen(safeset);
if ((extra = rule->envlist)) {
+ size_t i;
nextras = arraylen(extra);
for (i = 0; i < nsafe; i++) {
+ size_t j;
for (j = 0; j < nextras; j++) {
if (strcmp(extra[j], safeset[i]) == 0) {
extra[j--] = extra[nextras--];
int
main(int argc, char **argv, char **envp)
{
+ const char *safepath = "/bin:/sbin:/usr/bin:/usr/sbin:"
+ "/usr/local/bin:/usr/local/sbin";
+ char *shargv[] = { NULL, NULL };
+ char *sh;
+ const char *cmd;
char cmdline[LINE_MAX];
char myname[_PW_NAME_LEN + 1];
- uid_t uid, target = 0;
- gid_t groups[NGROUPS_MAX + 1];
- int ngroups;
struct passwd *pw;
struct rule *rule;
- const char *cmd;
+ uid_t uid;
+ uid_t target = 0;
+ gid_t groups[NGROUPS_MAX + 1];
+ int ngroups;
int i, ch;
- const char *safepath = "/bin:/sbin:/usr/bin:/usr/sbin:"
- "/usr/local/bin:/usr/local/sbin";
int sflag = 0;
- char *shargv[] = { NULL, NULL };
- char *sh;
-
- parseconfig("/etc/doas.conf");
- while ((ch = getopt(argc, argv, "su:")) != -1) {
+ uid = getuid();
+ while ((ch = getopt(argc, argv, "C:su:")) != -1) {
switch (ch) {
+ case 'C':
+ setresuid(uid, uid, uid);
+ parseconfig(optarg);
+ exit(0);
case 'u':
if (parseuid(optarg, &target) != 0)
errx(1, "unknown user");
if ((!sflag && !argc) || (sflag && argc))
usage();
- uid = getuid();
+ parseconfig("/etc/doas.conf");
+
pw = getpwuid(uid);
if (!pw)
err(1, "getpwuid failed");
errx(1, "command line too long");
}
- if (!permit(uid, groups, ngroups, &rule, target, cmd)) {
+ if (!permit(uid, groups, ngroups, &rule, target, cmd,
+ (const char**)argv + 1)) {
syslog(LOG_AUTHPRIV | LOG_NOTICE,
"failed command for %s: %s", myname, cmdline);
fail();
if (setenv("PATH", safepath, 1) == -1)
err(1, "failed to set PATH '%s'", safepath);
execvpe(cmd, argv, envp);
+ if (errno == ENOENT)
+ errx(1, "%s: command not found", cmd);
err(1, "%s", cmd);
}