]> git.armaanb.net Git - opendoas.git/blobdiff - doas.c
a few cleanups and simplifications possible now that static pw is gone. noted by...
[opendoas.git] / doas.c
diff --git a/doas.c b/doas.c
index ee1b341f7ba8b9eb13426a5dd16a70568a642805..1fd0e9a9c455ab62e32b738019cc2f3fbb14a947 100644 (file)
--- a/doas.c
+++ b/doas.c
 
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/ioctl.h>
 
 #include <limits.h>
+#if __OpenBSD__
+#      include <login_cap.h>
+#      include <readpassphrase.h>
+#endif
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.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 [-nsv] [-a style] [-C config] [-u user]"
-           " command [args]\n");
+       fprintf(stderr, "usage: doas [-Lns] "
+#ifdef __OpenBSD__
+           "[-a style] "
+#endif
+           "[-C config] [-u user] command [args]\n");
        exit(1);
 }
 
-size_t
-arraylen(const char **arr)
-{
-       size_t cnt = 0;
-
-       if (arr) {
-               while (*arr) {
-                       cnt++;
-                       arr++;
-               }
-       }
-       return cnt;
-}
-
 static int
 parseuid(const char *s, uid_t *uid)
 {
@@ -147,7 +134,7 @@ match(uid_t uid, gid_t *groups, int ngroups, uid_t target, const char *cmd,
 }
 
 static int
-permit(uid_t uid, gid_t *groups, int ngroups, struct rule **lastr,
+permit(uid_t uid, gid_t *groups, int ngroups, const struct rule **lastr,
     uid_t target, const char *cmd, const char **cmdargs)
 {
        int i;
@@ -194,7 +181,7 @@ 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;
+       const struct rule *rule;
 
        if (setresuid(uid, uid, uid) != 0)
                err(1, "setresuid");
@@ -213,6 +200,55 @@ checkconfig(const char *confpath, int argc, char **argv,
        }
 }
 
+#ifdef USE_BSD_AUTH
+static void
+authuser(char *myname, char *login_style, int persist)
+{
+       char *challenge = NULL, *response, rbuf[1024], cbuf[128];
+       auth_session_t *as;
+       int fd = -1;
+
+       if (persist)
+               fd = open("/dev/tty", O_RDWR);
+       if (fd != -1) {
+               if (ioctl(fd, TIOCCHKVERAUTH) == 0)
+                       goto good;
+       }
+
+       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,
+                   "tty required for %s", myname);
+               errx(1, "a tty is required");
+       }
+       if (!auth_userresponse(as, response, 0)) {
+               explicit_bzero(rbuf, sizeof(rbuf));
+               syslog(LOG_AUTHPRIV | LOG_NOTICE,
+                   "failed auth for %s", myname);
+               errx(1, "Authorization failed");
+       }
+       explicit_bzero(rbuf, sizeof(rbuf));
+good:
+       if (fd != -1) {
+               int secs = 5 * 60;
+               ioctl(fd, TIOCSETVERAUTH, &secs);
+               close(fd);
+       }
+}
+#endif
+
 int
 main(int argc, char **argv)
 {
@@ -223,42 +259,43 @@ main(int argc, char **argv)
        char *sh;
        const char *cmd;
        char cmdline[LINE_MAX];
-       char myname[_PW_NAME_LEN + 1];
-       struct passwd *pw;
-       struct rule *rule;
+#ifdef __OpenBSD__
+       char mypwbuf[_PW_BUF_LEN], targpwbuf[_PW_BUF_LEN];
+#else
+       char *mypwbuf = NULL, *targpwbuf = NULL;
+#endif
+       struct passwd mypwstore, targpwstore;
+       struct passwd *mypw, *targpw;
+       const struct rule *rule;
        uid_t uid;
        uid_t target = 0;
        gid_t groups[NGROUPS_MAX + 1];
        int ngroups;
-       int i, ch;
+       int i, ch, rv;
        int sflag = 0;
        int nflag = 0;
-       int vflag = 0;
        char cwdpath[PATH_MAX];
        const char *cwd;
        char **envp;
-#ifdef HAVE_BSD_AUTH_H
+#ifdef USE_BSD_AUTH
        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); */
+       closefrom(STDERR_FILENO + 1);
 
        uid = getuid();
 
-#ifdef HAVE_BSD_AUTH_H
-# define OPTSTRING "a:C:nsu:v"
+#ifdef USE_BSD_AUTH
+# define OPTSTRING "a:C:Lnsu:"
 #else
-# define OPTSTRING "C:nsu:v"
+# define OPTSTRING "+C:Lnsu:"
 #endif
 
        while ((ch = getopt(argc, argv, OPTSTRING)) != -1) {
                switch (ch) {
-#ifdef HAVE_BSD_AUTH_H
+#ifdef USE_BSD_AUTH
                case 'a':
                        login_style = optarg;
                        break;
@@ -266,6 +303,17 @@ main(int argc, char **argv)
                case 'C':
                        confpath = optarg;
                        break;
+               case 'L':
+#if defined(USE_BSD_AUTH)
+                       i = open("/dev/tty", O_RDWR);
+                       if (i != -1)
+                               ioctl(i, TIOCCLRVERAUTH);
+                       exit(i == -1);
+#elif defined(USE_TIMESTAMP)
+                       exit(timestamp_clear() == -1);
+#else
+                       exit(0);
+#endif
                case 'u':
                        if (parseuid(optarg, &target) != 0)
                                errx(1, "unknown user");
@@ -276,9 +324,6 @@ main(int argc, char **argv)
                case 's':
                        sflag = 1;
                        break;
-               case 'v':
-                       vflag = 1;
-                       break;
                default:
                        usage();
                        break;
@@ -287,20 +332,30 @@ main(int argc, char **argv)
        argv += optind;
        argc -= optind;
 
-       if (vflag)
-               version();
-
        if (confpath) {
                if (sflag)
                        usage();
        } else if ((!sflag && !argc) || (sflag && argc))
                usage();
 
-       pw = getpwuid(uid);
-       if (!pw)
-               err(1, "getpwuid failed");
-       if (strlcpy(myname, pw->pw_name, sizeof(myname)) >= sizeof(myname))
-               errx(1, "pw_name too long");
+#ifdef __OpenBSD__
+       rv = getpwuid_r(uid, &mypwstore, mypwbuf, sizeof(mypwbuf), &mypw);
+       if (rv != 0)
+               err(1, "getpwuid_r failed");
+#else
+       for (size_t sz = 1024; sz <= 16*1024; sz *= 2) {
+               mypwbuf = reallocarray(mypwbuf, sz, sizeof (char));
+               if (mypwbuf == NULL)
+                       errx(1, "can't allocate mypwbuf");
+               rv = getpwuid_r(uid, &mypwstore, mypwbuf, sz, &mypw);
+               if (rv != ERANGE)
+                       break;
+       }
+       if (rv != 0)
+               err(1, "getpwuid_r failed");
+#endif
+       if (mypw == NULL)
+               errx(1, "no passwd entry for self");
        ngroups = getgroups(NGROUPS_MAX, groups);
        if (ngroups == -1)
                err(1, "can't get groups");
@@ -308,9 +363,9 @@ main(int argc, char **argv)
 
        if (sflag) {
                sh = getenv("SHELL");
-               if (sh == NULL || *sh == '\0')
-                       shargv[0] = pw->pw_shell;
-               else
+               if (sh == NULL || *sh == '\0') {
+                       shargv[0] = mypw->pw_shell;
+               else
                        shargv[0] = sh;
                argv = shargv;
                argc = 1;
@@ -322,10 +377,13 @@ main(int argc, char **argv)
                exit(1);        /* fail safe */
        }
 
+       if (geteuid())
+               errx(1, "not installed setuid");
+
        parseconfig("/etc/doas.conf", 1);
 
        /* cmdline is used only for logging, no need to abort on truncate */
-       (void) strlcpy(cmdline, argv[0], sizeof(cmdline));
+       (void)strlcpy(cmdline, argv[0], sizeof(cmdline));
        for (i = 1; i < argc; i++) {
                if (strlcat(cmdline, " ", sizeof(cmdline)) >= sizeof(cmdline))
                        break;
@@ -335,89 +393,91 @@ main(int argc, char **argv)
 
        cmd = argv[0];
        if (!permit(uid, groups, ngroups, &rule, target, cmd,
-           (const char**)argv + 1)) {
+           (const char **)argv + 1)) {
                syslog(LOG_AUTHPRIV | LOG_NOTICE,
-                   "failed command for %s: %s", myname, cmdline);
+                   "failed command for %s: %s", mypw->pw_name, cmdline);
                errc(1, EPERM, NULL);
        }
 
-       pw = getpwuid(target);
-       if (!pw)
-               errx(1, "no passwd entry for target");
-
-#ifdef HAVE_BSD_AUTH_H
+#if defined(__OpenBSD__) || defined(USE_SHADOW)
        if (!(rule->options & NOPASS)) {
                if (nflag)
                        errx(1, "Authorization required");
 
-               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,
-                           "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));
-       }
-#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);
+# ifdef __OpenBSD__
+               authuser(mypw->pw_name, login_style, rule->options & PERSIST);
+# else
+               shadowauth(mypw->pw_name, rule->options & PERSIST);
+# endif
        }
-#else
-       if (!(rule->options & NOPASS)) {
-                       errx(1, "Authorization required");
-#endif /* HAVE_BSD_AUTH_H */
 
+# ifdef __OpenBSD__
        if (pledge("stdio rpath getpw exec id", NULL) == -1)
                err(1, "pledge");
+# endif
+
+#elif !defined(USE_PAM)
+       (void) nflag;
+       if (!(rule->options & NOPASS)) {
+               errx(1, "Authorization required");
+       }
+#endif /* !(__OpenBSD__ || USE_SHADOW) && !USE_PAM */
+
+#ifdef __OpenBSD__
+       rv = getpwuid_r(target, &targpwstore, targpwbuf, sizeof(targpwbuf), &targpw);
+       if (rv != 0)
+               errx(1, "no passwd entry for target");
+#else
+       for (size_t sz = 1024; sz <= 16*1024; sz *= 2) {
+               targpwbuf = reallocarray(targpwbuf, sz, sizeof (char));
+               if (targpwbuf == NULL)
+                       errx(1, "can't allocate targpwbuf");
+               rv = getpwuid_r(target, &targpwstore, targpwbuf, sz, &targpw);
+               if (rv != ERANGE)
+                       break;
+       }
+       if (rv != 0)
+               err(1, "getpwuid_r failed");
+#endif
+       if (targpw == NULL)
+               err(1, "getpwuid_r failed");
+
+#if defined(USE_PAM)
+       pamauth(targpw->pw_name, mypw->pw_name, !nflag, rule->options & NOPASS,
+           rule->options & PERSIST);
+#endif
 
-#ifdef HAVE_BSD_AUTH_H
-       if (setusercontext(NULL, pw, target, LOGIN_SETGROUP |
+#ifdef HAVE_SETUSERCONTEXT
+       if (setusercontext(NULL, targpw, 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 (setresgid(targpw->pw_gid, targpw->pw_gid, targpw->pw_gid) != 0)
+               err(1, "setresgid");
+       if (initgroups(targpw->pw_name, targpw->pw_gid) != 0)
+               err(1, "initgroups");
        if (setresuid(target, target, target) != 0)
-               errx(1, "setuid");
+               err(1, "setresuid");
 #endif
 
+#ifdef __OpenBSD__
        if (pledge("stdio rpath exec", NULL) == -1)
                err(1, "pledge");
+#endif
 
        if (getcwd(cwdpath, sizeof(cwdpath)) == NULL)
                cwd = "(failed)";
        else
                cwd = cwdpath;
 
+#ifdef __OpenBSD__
        if (pledge("stdio exec", NULL) == -1)
                err(1, "pledge");
+#endif
 
        syslog(LOG_AUTHPRIV | LOG_INFO, "%s ran command %s as %s from %s",
-           myname, cmdline, pw->pw_name, cwd);
+           mypw->pw_name, cmdline, targpw->pw_name, cwd);
 
        envp = prepenv(rule);