From: Todd C. Miller Date: Mon, 31 Jul 2006 17:50:06 +0000 (+0000) Subject: Add seteuid() flavor of set_perms() for systems without setreuid() X-Git-Tag: SUDO_1_7_0~591 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ea8c5d5d2d771bf0e13dfaba3f2af0c4164098f7;p=sudo Add seteuid() flavor of set_perms() for systems without setreuid() or setresuid() that have a working seteuid(). Tested on Darwin. --- diff --git a/config.h.in b/config.h.in index be13ad794..16eeb64d2 100644 --- a/config.h.in +++ b/config.h.in @@ -260,6 +260,9 @@ /* Define to 1 if you use SecurID for authentication. */ #undef HAVE_SECURID +/* Define to 1 if you have the `seteuid' function. */ +#undef HAVE_SETEUID + /* Define to 1 if you have the `setlocale' function. */ #undef HAVE_SETLOCALE diff --git a/configure b/configure index c57864ae0..af041dcc2 100755 --- a/configure +++ b/configure @@ -14238,6 +14238,110 @@ else echo "$as_me: failed program was:" >&5 sed 's/^/| /' conftest.$ac_ext >&5 +eval "$as_ac_var=no" +fi +rm -f conftest.err conftest.$ac_objext \ + conftest$ac_exeext conftest.$ac_ext +fi +echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_var'}'`" >&5 +echo "${ECHO_T}`eval echo '${'$as_ac_var'}'`" >&6 +if test `eval echo '${'$as_ac_var'}'` = yes; then + cat >>confdefs.h <<_ACEOF +#define `echo "HAVE_$ac_func" | $as_tr_cpp` 1 +_ACEOF + SKIP_SETEUID=yes +fi +done + +fi +if test -z "$SKIP_SETEUID"; then + +for ac_func in seteuid +do +as_ac_var=`echo "ac_cv_func_$ac_func" | $as_tr_sh` +echo "$as_me:$LINENO: checking for $ac_func" >&5 +echo $ECHO_N "checking for $ac_func... $ECHO_C" >&6 +if eval "test \"\${$as_ac_var+set}\" = set"; then + echo $ECHO_N "(cached) $ECHO_C" >&6 +else + cat >conftest.$ac_ext <<_ACEOF +/* confdefs.h. */ +_ACEOF +cat confdefs.h >>conftest.$ac_ext +cat >>conftest.$ac_ext <<_ACEOF +/* end confdefs.h. */ +/* Define $ac_func to an innocuous variant, in case declares $ac_func. + For example, HP-UX 11i declares gettimeofday. */ +#define $ac_func innocuous_$ac_func + +/* System header to define __stub macros and hopefully few prototypes, + which can conflict with char $ac_func (); below. + Prefer to if __STDC__ is defined, since + exists even on freestanding compilers. */ + +#ifdef __STDC__ +# include +#else +# include +#endif + +#undef $ac_func + +/* Override any gcc2 internal prototype to avoid an error. */ +#ifdef __cplusplus +extern "C" +{ +#endif +/* We use char because int might match the return type of a gcc2 + builtin and then its argument prototype would still apply. */ +char $ac_func (); +/* The GNU C library defines this for functions which it implements + to always fail with ENOSYS. Some functions are actually named + something starting with __ and the normal name is an alias. */ +#if defined (__stub_$ac_func) || defined (__stub___$ac_func) +choke me +#else +char (*f) () = $ac_func; +#endif +#ifdef __cplusplus +} +#endif + +int +main () +{ +return f != $ac_func; + ; + return 0; +} +_ACEOF +rm -f conftest.$ac_objext conftest$ac_exeext +if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5 + (eval $ac_link) 2>conftest.er1 + ac_status=$? + grep -v '^ *+' conftest.er1 >conftest.err + rm -f conftest.er1 + cat conftest.err >&5 + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); } && + { ac_try='test -z "$ac_c_werror_flag" + || test ! -s conftest.err' + { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5 + (eval $ac_try) 2>&5 + ac_status=$? + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); }; } && + { ac_try='test -s conftest$ac_exeext' + { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5 + (eval $ac_try) 2>&5 + ac_status=$? + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); }; }; then + eval "$as_ac_var=yes" +else + echo "$as_me: failed program was:" >&5 +sed 's/^/| /' conftest.$ac_ext >&5 + eval "$as_ac_var=no" fi rm -f conftest.err conftest.$ac_objext \ diff --git a/configure.in b/configure.in index 6e6cf7399..40df095bf 100644 --- a/configure.in +++ b/configure.in @@ -1696,7 +1696,10 @@ if test -z "$SKIP_SETRESUID"; then AC_CHECK_FUNCS(setresuid, [SKIP_SETREUID=yes]) fi if test -z "$SKIP_SETREUID"; then - AC_CHECK_FUNCS(setreuid) + AC_CHECK_FUNCS(setreuid, [SKIP_SETEUID=yes]) +fi +if test -z "$SKIP_SETEUID"; then + AC_CHECK_FUNCS(seteuid) fi if test X"$with_interfaces" != X"no"; then AC_CHECK_FUNCS(getifaddrs, [AC_CHECK_FUNCS(freeifaddrs)]) diff --git a/set_perms.c b/set_perms.c index 42b181194..9cd5b8513 100644 --- a/set_perms.c +++ b/set_perms.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 1994-1996,1998-2005 Todd C. Miller + * Copyright (c) 1994-1996,1998-2006 Todd C. Miller * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above @@ -214,6 +214,84 @@ set_perms(perm) } # else /* !HAVE_SETRESUID && !HAVE_SETREUID */ +# ifdef HAVE_SETEUID + +/* + * Set real and effective uids and gids based on perm. + * NOTE: does not support the "stay_setuid" option. + */ +void +set_perms(perm) + int perm; +{ + /* + * Since we only have setuid() and seteuid() and semantics + * for these calls differ on various systems, we set + * real and effective uids to ROOT_UID initially to be safe. + */ + if (seteuid(ROOT_UID)) + error(1, "seteuid(ROOT_UID)"); + if (setuid(ROOT_UID)) + error(1, "setuid(ROOT_UID)"); + + switch (perm) { + case PERM_FULL_ROOT: + case PERM_ROOT: + /* already set above */ + break; + + case PERM_USER: + (void) setegid(user_gid); + if (seteuid(user_uid)) + error(1, "seteuid(user_uid)"); + break; + + case PERM_FULL_USER: + /* headed for exec() */ + (void) setgid(user_gid); + if (setuid(user_uid)) + error(1, "setuid(user_uid)"); + break; + + case PERM_RUNAS: + if (seteuid(runas_pw->pw_uid)) + error(1, "unable to change to runas uid"); + break; + + case PERM_FULL_RUNAS: + /* headed for exec() */ + runas_setup(); + if (setuid(runas_pw->pw_uid)) + error(1, "unable to change to runas uid"); + break; + + case PERM_SUDOERS: + if (setegid(SUDOERS_GID)) + error(1, "unable to change to sudoers gid"); + + /* + * If SUDOERS_UID == ROOT_UID and SUDOERS_MODE + * is group readable we use a non-zero + * uid in order to avoid NFS lossage. + * Using uid 1 is a bit bogus but should + * work on all OS's. + */ + if (SUDOERS_UID == ROOT_UID) { + if ((SUDOERS_MODE & 040) && seteuid(1)) + error(1, "seteuid(1)"); + } else { + if (seteuid(SUDOERS_UID)) + error(1, "seteuid(SUDOERS_UID)"); + } + break; + case PERM_TIMESTAMP: + if (seteuid(timestamp_uid)) + error(1, "seteuid(timestamp_uid)"); + break; + } +} + +# else /* !HAVE_SETRESUID && !HAVE_SETREUID && !HAVE_SETEUID */ /* * Set uids and gids based on perm via setuid() and setgid(). @@ -252,6 +330,7 @@ set_perms(perm) break; } } +# endif /* HAVE_SETEUID */ # endif /* HAVE_SETREUID */ #endif /* HAVE_SETRESUID */