]> git.armaanb.net Git - opendoas.git/blobdiff - doas.c
open pam sessions with right user and remove setusercontext shim
[opendoas.git] / doas.c
diff --git a/doas.c b/doas.c
index 6fabd7bf1b9887dbf65f1d60f1f8cd906623b455..f1b2ec058be2bb7d992679c523ca0b08334e094a 100644 (file)
--- a/doas.c
+++ b/doas.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: doas.c,v 1.32 2015/07/29 00:00:31 tedu Exp $ */
+/* $OpenBSD: doas.c,v 1.52 2016/04/28 04:48:56 tedu Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
  *
 #include <syslog.h>
 #include <errno.h>
 
-#include "openbsd.h"
+#include "includes.h"
 
 #include "doas.h"
 
+static void __dead
+version(void)
+{
+       fprintf(stderr, "doas: version %s built %s\n", VERSION, __DATE__);
+       exit(1);
+}
+
 static void __dead
 usage(void)
 {
-       fprintf(stderr, "usage: doas [-ns] [-C config] [-u user] command [args]\n");
+       fprintf(stderr, "usage: doas [-nsv] [-a style] [-C config] [-u user]"
+           " command [args]\n");
        exit(1);
 }
 
@@ -163,10 +171,9 @@ parseconfig(const char *filename, int checkperms)
        struct stat sb;
 
        yyfp = fopen(filename, "r");
-       if (!yyfp) {
-               warn("could not open config file");
-               exit(1);
-       }
+       if (!yyfp)
+               err(1, checkperms ? "doas is not enabled, %s" :
+                   "could not open config file %s", filename);
 
        if (checkperms) {
                if (fstat(fileno(yyfp), &sb) != 0)
@@ -282,20 +289,15 @@ copyenv(const char **oldenvp, struct rule *rule)
        return envp;
 }
 
-static void __dead
-fail(void)
-{
-       fprintf(stderr, "Permission denied\n");
-       exit(1);
-}
-
 static void __dead
 checkconfig(const char *confpath, int argc, char **argv,
     uid_t uid, gid_t *groups, int ngroups, uid_t target)
 {
        struct rule *rule;
 
-       setresuid(uid, uid, uid);
+       if (setresuid(uid, uid, uid) != 0)
+               err(1, "setresuid");
+
        parseconfig(confpath, 0);
        if (!argc)
                exit(0);
@@ -330,10 +332,35 @@ main(int argc, char **argv, char **envp)
        int i, ch;
        int sflag = 0;
        int nflag = 0;
+       int vflag = 0;
+       char cwdpath[PATH_MAX];
+       const char *cwd;
+#ifdef HAVE_BSD_AUTH_H
+       char *login_style = NULL;
+#endif
+
+       setprogname("doas");
+
+       if (pledge("stdio rpath getpw tty proc exec id", NULL) == -1)
+               err(1, "pledge");
+
+       /* closefrom(STDERR_FILENO + 1); */
 
        uid = getuid();
-       while ((ch = getopt(argc, argv, "C:nsu:")) != -1) {
+
+#ifdef HAVE_BSD_AUTH_H
+# define OPTSTRING "a:C:nsu:v"
+#else
+# define OPTSTRING "C:nsu:v"
+#endif
+
+       while ((ch = getopt(argc, argv, OPTSTRING)) != -1) {
                switch (ch) {
+#ifdef HAVE_BSD_AUTH_H
+               case 'a':
+                       login_style = optarg;
+                       break;
+#endif
                case 'C':
                        confpath = optarg;
                        break;
@@ -347,6 +374,9 @@ main(int argc, char **argv, char **envp)
                case 's':
                        sflag = 1;
                        break;
+               case 'v':
+                       vflag = 1;
+                       break;
                default:
                        usage();
                        break;
@@ -355,13 +385,15 @@ main(int argc, char **argv, char **envp)
        argv += optind;
        argc -= optind;
 
+       if (vflag)
+               version();
+
        if (confpath) {
                if (sflag)
                        usage();
        } else if ((!sflag && !argc) || (sflag && argc))
                usage();
 
-       uid = getuid();
        pw = getpwuid(uid);
        if (!pw)
                err(1, "getpwuid failed");
@@ -404,32 +436,93 @@ main(int argc, char **argv, char **envp)
            (const char**)argv + 1)) {
                syslog(LOG_AUTHPRIV | LOG_NOTICE,
                    "failed command for %s: %s", myname, cmdline);
-               fail();
+               errc(1, EPERM, NULL);
        }
 
+       pw = getpwuid(target);
+       if (!pw)
+               errx(1, "no passwd entry for target");
+
+#ifdef HAVE_BSD_AUTH_H
        if (!(rule->options & NOPASS)) {
                if (nflag)
                        errx(1, "Authorization required");
-               if (!auth_userokay(myname, NULL, NULL, NULL)) {
+
+               char *challenge = NULL, *response, rbuf[1024], cbuf[128];
+               auth_session_t *as;
+
+               if (!(as = auth_userchallenge(myname, login_style, "auth-doas",
+                   &challenge)))
+                       errx(1, "Authorization failed");
+               if (!challenge) {
+                       char host[HOST_NAME_MAX + 1];
+                       if (gethostname(host, sizeof(host)))
+                               snprintf(host, sizeof(host), "?");
+                       snprintf(cbuf, sizeof(cbuf),
+                           "\rdoas (%.32s@%.32s) password: ", myname, host);
+                       challenge = cbuf;
+               }
+               response = readpassphrase(challenge, rbuf, sizeof(rbuf),
+                   RPP_REQUIRE_TTY);
+               if (response == NULL && errno == ENOTTY) {
                        syslog(LOG_AUTHPRIV | LOG_NOTICE,
-                           "failed password for %s", myname);
-                       fail();
+                           "tty required for %s", myname);
+                       errx(1, "a tty is required");
                }
+               if (!auth_userresponse(as, response, 0)) {
+                       syslog(LOG_AUTHPRIV | LOG_NOTICE,
+                           "failed auth for %s", myname);
+                       errc(1, EPERM, NULL);
+               }
+               explicit_bzero(rbuf, sizeof(rbuf));
        }
-       envp = copyenv((const char **)envp, rule);
+#elif HAVE_PAM_APPL_H
+       if (!doas_pam(pw->pw_name, myname, !nflag, rule->options & NOPASS)) {
+               syslog(LOG_AUTHPRIV | LOG_NOTICE, "failed auth for %s", myname);
+               errc(1, EPERM, NULL);
+       }
+#else
+       if (!(rule->options & NOPASS)) {
+                       errx(1, "Authorization required");
+#endif /* HAVE_BSD_AUTH_H */
 
-       pw = getpwuid(target);
-       if (!pw)
-               errx(1, "no passwd entry for target");
+       if (pledge("stdio rpath getpw exec id", NULL) == -1)
+               err(1, "pledge");
+
+#ifdef HAVE_BSD_AUTH_H
        if (setusercontext(NULL, pw, target, LOGIN_SETGROUP |
            LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | LOGIN_SETUMASK |
            LOGIN_SETUSER) != 0)
                errx(1, "failed to set user context for target");
+#else
+       if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0)
+               errx(1, "setgid");
+       if (initgroups(pw->pw_name, pw->pw_gid) != 0)
+               errx(1, "initgroups");
+       if (setresuid(target, target, target) != 0)
+               errx(1, "setuid");
+#endif
+
+       if (pledge("stdio rpath exec", NULL) == -1)
+               err(1, "pledge");
+
+       if (getcwd(cwdpath, sizeof(cwdpath)) == NULL)
+               cwd = "(failed)";
+       else
+               cwd = cwdpath;
 
-       syslog(LOG_AUTHPRIV | LOG_INFO, "%s ran command as %s: %s",
-           myname, pw->pw_name, cmdline);
-       if (setenv("PATH", safepath, 1) == -1)
-               err(1, "failed to set PATH '%s'", safepath);
+       if (pledge("stdio exec", NULL) == -1)
+               err(1, "pledge");
+
+       syslog(LOG_AUTHPRIV | LOG_INFO, "%s ran command %s as %s from %s",
+           myname, cmdline, pw->pw_name, cwd);
+
+       envp = copyenv((const char **)envp, rule);
+
+       if (rule->cmd) {
+               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);