X-Git-Url: https://git.armaanb.net/?p=opendoas.git;a=blobdiff_plain;f=doas.c;h=d348d2554b6f23a5c364ccccc8c8ce64cc09bf58;hp=6c1b14d3f36b234c2d37c22479a8af226c43118d;hb=HEAD;hpb=be6639289c38a69b5edbb4d40d0bc3c56360379c diff --git a/doas.c b/doas.c index 6c1b14d..d348d25 100644 --- a/doas.c +++ b/doas.c @@ -15,11 +15,16 @@ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ +#include "config.h" + #include #include #include #include +#ifdef HAVE_LOGIN_CAP_H +#include +#endif #include #include #include @@ -29,29 +34,17 @@ #include #include #include -#if HAVE_SHADOW_H -#include -#endif - -#include "includes.h" +#include +#include +#include "openbsd.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 [-Lnsv] " -#ifdef HAVE_BSD_AUTH_H - "[-a style] " -#endif - "[-C config] [-u user] command [args]\n"); + fprintf(stderr, "usage: doas [-Lns] [-C config] [-u user]" + " command [args]\n"); exit(1); } @@ -63,9 +56,11 @@ parseuid(const char *s, uid_t *uid) if ((pw = getpwnam(s)) != NULL) { *uid = pw->pw_uid; + if (*uid == UID_MAX) + return -1; return 0; } - *uid = strtonum(s, 0, UID_MAX, &errstr); + *uid = strtonum(s, 0, UID_MAX - 1, &errstr); if (errstr) return -1; return 0; @@ -91,9 +86,11 @@ parsegid(const char *s, gid_t *gid) if ((gr = getgrnam(s)) != NULL) { *gid = gr->gr_gid; + if (*gid == GID_MAX) + return -1; return 0; } - *gid = strtonum(s, 0, GID_MAX, &errstr); + *gid = strtonum(s, 0, GID_MAX - 1, &errstr); if (errstr) return -1; return 0; @@ -140,10 +137,10 @@ 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; + size_t i; *lastr = NULL; for (i = 0; i < nrules; i++) { @@ -160,6 +157,7 @@ static void parseconfig(const char *filename, int checkperms) { extern FILE *yyfp; + extern int yyparse(void); struct stat sb; yyfp = fopen(filename, "r"); @@ -186,7 +184,7 @@ 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"); @@ -205,98 +203,50 @@ checkconfig(const char *confpath, int argc, char **argv, } } -#ifdef HAVE_BSD_AUTH_H -static void -authuser(char *myname, char *login_style, int persist) +int +mygetpwuid_r(uid_t uid, struct passwd *pwd, struct passwd **result) { - 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; + int rv; + char *buf; + static long pwsz = 0; + size_t buflen; + + *result = NULL; + + if (pwsz == 0) + pwsz = sysconf(_SC_GETPW_R_SIZE_MAX); + + buflen = pwsz > 0 ? pwsz : 1024; + + buf = malloc(buflen); + if (buf == NULL) + return errno; + + while ((rv = getpwuid_r(uid, pwd, buf, buflen, result)) == ERANGE) { + size_t newsz; + newsz = buflen * 2; + if (newsz < buflen) + return rv; + buflen = newsz; + buf = realloc(buf, buflen); + if (buf == NULL) + return errno; } - 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)); -good: - if (fd != -1) { - int secs = 5 * 60; - ioctl(fd, TIOCSETVERAUTH, &secs); - close(fd); - } + return rv; } -#elif HAVE_SHADOW_H -static void -authuser(const char *myname, const char *login_style, int persist) -{ - const char *hash; - char *encrypted; - struct passwd *pw; - - (void)login_style; - (void)persist; - - if (!(pw = getpwnam(myname))) - err(1, "getpwnam"); - hash = pw->pw_passwd; - if (hash[0] == 'x' && hash[1] == '\0') { - struct spwd *sp; - if (!(sp = getspnam(myname))) - errx(1, "Authorization failed"); - hash = sp->sp_pwdp; - } else if (hash[0] != '*') { - errx(1, "Authorization failed"); - } +void +authfail(int opt) +{ - char *challenge, *response, rbuf[1024], cbuf[128], 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; +#ifdef DOAS_INSULTS + if (opt) + printf("%s\n", getinsult()); +#endif - 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 (!(encrypted = crypt(response, hash))) - errx(1, "crypt"); - if (strcmp(encrypted, hash) != 0) { - syslog(LOG_AUTHPRIV | LOG_NOTICE, "failed auth for %s", myname); - errx(1, "Authorization failed"); - } - explicit_bzero(rbuf, sizeof(rbuf)); + errx(1, "Authentication failed"); } -#endif /* HAVE_BSD_AUTH_H */ int main(int argc, char **argv) @@ -306,23 +256,27 @@ main(int argc, char **argv) const char *confpath = NULL; char *shargv[] = { NULL, NULL }; char *sh; + const char *p; const char *cmd; char cmdline[LINE_MAX]; - char myname[_PW_NAME_LEN + 1]; - struct passwd *pw; - struct rule *rule; + 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; - char *login_style = NULL; + + if (argc <= 0 || argv == NULL || argv[0] == NULL) { + fprintf(stderr, "doas: executed without argv\n"); + exit(1); + } setprogname("doas"); @@ -330,28 +284,16 @@ main(int argc, char **argv) uid = getuid(); -#ifdef HAVE_BSD_AUTH_H -# define OPTSTRING "a:C:Lnsu:v" -#else -# define OPTSTRING "+C:Lnsu:v" -#endif - - while ((ch = getopt(argc, argv, OPTSTRING)) != -1) { + while ((ch = getopt(argc, argv, "+C:Lnsu:")) != -1) { switch (ch) { -#ifdef HAVE_BSD_AUTH_H - case 'a': - login_style = optarg; - break; -#endif case 'C': confpath = optarg; break; case 'L': -#ifdef TIOCCLRVERAUTH - i = open("/dev/tty", O_RDWR); - if (i != -1) - ioctl(i, TIOCCLRVERAUTH); - exit(i == -1); +#if defined(USE_TIMESTAMP) + exit(timestamp_clear() == -1); +#else + exit(0); #endif case 'u': if (parseuid(optarg, &target) != 0) @@ -363,9 +305,6 @@ main(int argc, char **argv) case 's': sflag = 1; break; - case 'v': - vflag = 1; - break; default: usage(); break; @@ -374,20 +313,17 @@ 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"); + rv = mygetpwuid_r(uid, &mypwstore, &mypw); + if (rv != 0) + err(1, "getpwuid_r failed"); + if (mypw == NULL) + errx(1, "no passwd entry for self"); ngroups = getgroups(NGROUPS_MAX, groups); if (ngroups == -1) err(1, "can't get groups"); @@ -396,9 +332,7 @@ main(int argc, char **argv) if (sflag) { sh = getenv("SHELL"); if (sh == NULL || *sh == '\0') { - shargv[0] = strdup(pw->pw_shell); - if (shargv[0] == NULL) - err(1, NULL); + shargv[0] = mypw->pw_shell; } else shargv[0] = sh; argv = shargv; @@ -411,7 +345,10 @@ main(int argc, char **argv) exit(1); /* fail safe */ } - parseconfig("/etc/doas.conf", 1); + if (geteuid()) + errx(1, "not installed setuid"); + + parseconfig(DOAS_CONF, 1); /* cmdline is used only for logging, no need to abort on truncate */ (void)strlcpy(cmdline, argv[0], sizeof(cmdline)); @@ -426,70 +363,72 @@ main(int argc, char **argv) if (!permit(uid, groups, ngroups, &rule, target, cmd, (const char **)argv + 1)) { syslog(LOG_AUTHPRIV | LOG_NOTICE, - "failed command for %s: %s", myname, cmdline); + "command not permitted for %s: %s", mypw->pw_name, cmdline); errc(1, EPERM, NULL); } -#if defined(HAVE_BSD_AUTH_H) || defined(HAVE_SHADOW_H) if (!(rule->options & NOPASS)) { if (nflag) - errx(1, "Authorization required"); + errx(1, "Authentication required"); - authuser(myname, login_style, rule->options & PERSIST); + int ret = shadowauth(mypw->pw_name, rule->options & PERSIST); + if (ret == 5) + authfail(rule->options & INSULT); } -#elif HAVE_PAM_APPL_H - pw = getpwuid(target); - if (!pw) - errx(1, "no passwd entry for target"); - if (!pamauth(pw->pw_name, myname, !nflag, rule->options & NOPASS)) { - syslog(LOG_AUTHPRIV | LOG_NOTICE, "failed auth for %s", myname); - errx(1, "Authorization failed"); - } -#else -#error "No authentication method" -#endif /* HAVE_BSD_AUTH_H */ + if ((p = getenv("PATH")) != NULL) + formerpath = strdup(p); + if (formerpath == NULL) + formerpath = ""; - if (pledge("stdio rpath getpw exec id", NULL) == -1) - err(1, "pledge"); + if (rule->cmd) { + if (setenv("PATH", safepath, 1) == -1) + err(1, "failed to set PATH '%s'", safepath); + } - pw = getpwuid(target); - if (!pw) + rv = mygetpwuid_r(target, &targpwstore, &targpw); + if (rv != 0) + err(1, "getpwuid_r failed"); + if (targpw == NULL) errx(1, "no passwd entry for target"); -#ifdef HAVE_BSD_AUTH_H - if (setusercontext(NULL, pw, target, LOGIN_SETGROUP | +#ifdef HAVE_LOGIN_CAP_H + if (setusercontext(NULL, targpw, target, LOGIN_SETGROUP | + LOGIN_SETPATH | 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, "setresgid"); - 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, "setresuid"); + err(1, "setresuid"); + if (setenv("PATH", safepath, 1) == -1) + err(1, "failed to set PATH '%s'", safepath); #endif - if (pledge("stdio rpath exec", NULL) == -1) - err(1, "pledge"); - if (getcwd(cwdpath, sizeof(cwdpath)) == NULL) cwd = "(failed)"; else cwd = cwdpath; - 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); + if (!(rule->options & NOLOG)) { + syslog(LOG_AUTHPRIV | LOG_INFO, + "%s ran command %s as %s from %s", + mypw->pw_name, cmdline, targpw->pw_name, cwd); + } - envp = prepenv(rule); + envp = prepenv(rule, mypw, targpw); + /* setusercontext set path for the next process, so reset it for us */ if (rule->cmd) { if (setenv("PATH", safepath, 1) == -1) err(1, "failed to set PATH '%s'", safepath); + } else { + if (setenv("PATH", formerpath, 1) == -1) + err(1, "failed to set PATH '%s'", formerpath); } execvpe(cmd, argv, envp); if (errno == ENOENT)