Restrict option umask to the address it is applied to

CHANGES

@@ -143,6 +143,11 @@ Features:
 	Added option res-nsaddr that overrides /etc/resolv.conf nameserver
 	address based on an undocumented resolver feature.
 
+	Option umask now applies only during opening of its very address, not
+	for the lifetime of the process; the original umask is restored
+	afterwards.
+	Tests: UMASK_ON_CREATE UMASK_ON_SYSTEM
+
 Corrections:
 	When a sub process (EXEC, SYSTEM) terminated with exit code other than
 	0, its last sent data might have been lost depending on timing of read/

doc/socat.yo

@@ -341,6 +341,7 @@ label(ADDRESS_EXEC)dit(bf(tt(EXEC:<command-line>)))
    link(ctty)(OPTION_CTTY),
    link(setsid)(OPTION_SETSID),
    link(pipes)(OPTION_PIPES),
+   link(umask)(OPTION_UMASK),
    link(login)(OPTION_LOGIN),
    link(sigint)(OPTION_SIGINT),
    link(sigquit)(OPTION_SIGQUIT),
@@ -1111,6 +1112,7 @@ label(ADDRESS_SHELL)dit(bf(tt(SHELL:<shell-command>)))
    link(ctty)(OPTION_CTTY),
    link(setsid)(OPTION_SETSID),
    link(pipes)(OPTION_PIPES),
+   link(umask)(OPTION_UMASK),
    link(sigint)(OPTION_SIGINT),
    link(sigquit)(OPTION_SIGQUIT)nl()
    See also: link(EXEC)(ADDRESS_EXEC), link(SYSTEM)(ADDRESS_SYSTEM)
@@ -1137,6 +1139,7 @@ label(ADDRESS_SYSTEM)dit(bf(tt(SYSTEM:<shell-command>)))
    link(ctty)(OPTION_CTTY),
    link(setsid)(OPTION_SETSID),
    link(pipes)(OPTION_PIPES),
+   link(umask)(OPTION_UMASK),
    link(sigint)(OPTION_SIGINT),
    link(sigquit)(OPTION_SIGQUIT),
    link(netns)(OPTION_NETNS)nl()
@@ -1503,6 +1506,7 @@ label(ADDRESS_UNIX_RECVFROM)dit(bf(tt(UNIX-RECVFROM:<filename>)))
    See the link(note about RECVFROM addresses)(NOTE_RECVFROM).nl()
    Useful options:
    link(fork)(OPTION_FORK)nl()
+   link(umask)(OPTION_UMASK)nl()
    See also:
    link(UNIX-SENDTO)(ADDRESS_UNIX_SENDTO),
    link(UNIX-RECV)(ADDRESS_UNIX_RECV),
@@ -1518,6 +1522,8 @@ label(ADDRESS_UNIX_RECV)dit(bf(tt(UNIX-RECV:<filename>)))
    It can be, e.g., addressed by socat UNIX-SENDTO address peers.
    It behaves similar to a syslog server.nl()
    Option groups: link(FD)(GROUP_FD),link(SOCKET)(GROUP_SOCKET),link(NAMED)(GROUP_NAMED),link(UNIX)(GROUP_SOCK_UNIX) nl()
+   Useful options:
+   link(umask)(OPTION_UMASK)nl()
    See also:
    link(UNIX-SENDTO)(ADDRESS_UNIX_SENDTO),
    link(UNIX-RECVFROM)(ADDRESS_UNIX_RECVFROM),
@@ -1856,11 +1862,6 @@ label(OPTION_PERM_EARLY)dit(bf(tt(perm-early=<mode>)))
    before accessing it, using the 
    code(chmod()) system call. This call might require ownership or root
    privilege. 
-label(OPTION_UMASK)dit(bf(tt(umask=<mode>)))
-   Sets the umask of the process to <mode> [link(mode_t)(TYPE_MODE_T)] before
-   accessing the file system entry (useful 
-   with unixdomain() sockets!). This call might affect all further operations
-   of the socat() process!  
 label(OPTION_UNLINK_EARLY)dit(bf(tt(unlink-early[=<bool>])))
    Unlinks (removes) the file before opening it and even before applying
    user-early etc. 
@@ -1983,6 +1984,24 @@ enddit()
 startdit()enddit()nl()
 
 
+label(GROUP_ADDRS)em(bf(General address options))
+
+These options may be applied to all address types. They change some process
+properties that are restored after opening the address.
+
+startdit()
+label(OPTION_UMASK)dit(bf(tt(umask=<mode>)))
+   Sets the umask of the process to <mode> [link(mode_t)(TYPE_MODE_T)] before
+   opening the address. Useful when file system entries are created or a shell
+   or program is invoked. Usually the value is specified as octal number.nl()
+   The processes tt(umask) value is inherited by child processes.
+   Note: umask is an inverted value: creating a file with umask=0026 results in
+   permissions 0640.
+enddit()
+
+startdit()enddit()nl()
+
+
 label(GROUP_PROCESS)em(bf(PROCESS option group))
 
 Options of this group change the process properties instead of just affecting

test.sh

@@ -17355,6 +17355,161 @@ else
     listFAIL="$listFAIL $N"
     namesFAIL="$namesFAIL $NAME"
 fi
+
+
+# Test the modified umask option, in particular if umask with first address
+# (CREATE) does not affect umask of second address, i.e. original umask is
+# recovered
+NAME=UMASK_ON_CREATE
+case "$TESTS" in
+*%$N%*|*%functions%*|*%creat%*|*%system%*|*%umask%*|*%$NAME%*)
+TEST="$NAME: test restore after CREAT with umask option"
+# Run Socat with first address CREAT with modified umask,
+# and second address SYSTEM (shell) with umask command
+# Check if the file is created with modified umask but shell has original umask
+if ! eval $NUMCOND; then :;
+elif ! F=$(testfeats CREAT SYSTEM); then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Feature $F not configured in $SOCAT${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
+elif ! A=$(testaddrs - CREAT SYSTEM); then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Address $A not available in $SOCAT${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
+elif ! o=$(testoptions umask) >/dev/null; then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Option $o not available in $SOCAT${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
+else
+    tf="$td/test$N.stdout"
+    te="$td/test$N.stderr"
+    tc="$td/test$N.creat"
+    tdiff="$td/test$N.diff"
+    tdebug="$td/test$N.debug"
+    oumask=$(umask)
+    # Construct a temp umask differing from original umask
+    case oumask in
+	*066) tumask=0026 ;;
+	*)    tumask=0066 ;;
+    esac
+    CMD0="$TRACE $SOCAT $opts -U CREAT:$tc,umask=$tumask SYSTEM:umask"
+    printf "test $F_n $TEST... " $N
+    $CMD0 >/dev/null 2>"${te}0"
+    rc0=$?
+    tperms=$(fileperms $tc)
+    case $tperms in
+	0*) ;;
+	*) tperms=0$tperms ;;
+    esac
+    echo "Original umask:  $oumask" >>$tdebug
+    echo "Temporary umask: $tumask" >>$tdebug
+    echo "Created umask:   $tperms" >>$tdebug
+    if [ "$rc0" -ne 0 ]; then
+	$PRINTF "$FAILED\n"
+	echo "$CMD0 &"
+	cat "${te}0" >&2
+	numFAIL=$((numFAIL+1))
+	listFAIL="$listFAIL $N"
+	namesFAIL="$namesFAIL $NAME"
+    elif [ $((tumask + tperms - 0666)) -ne 0 ]; then
+	$PRINTF "$FAILED (umask failed)\n"
+	echo "$CMD0 &"
+	cat "${te}0" >&2
+	numFAIL=$((numFAIL+1))
+	listFAIL="$listFAIL $N"
+	namesFAIL="$namesFAIL $NAME"
+    elif ! echo "$oumask" |diff "$tc" - >$tdiff; then
+	$PRINTF "$FAILED (bad umask)\n"
+	echo "$CMD0 &"
+	cat "${te}0" >&2
+	numFAIL=$((numFAIL+1))
+	listFAIL="$listFAIL $N"
+	namesFAIL="$namesFAIL $NAME"
+    else
+	$PRINTF "$OK\n"
+	if [ "$VERBOSE" ]; then echo "$CMD0 &"; fi
+	if [ "$DEBUG" ];   then cat "${te}0" >&2; fi
+	numOK=$((numOK+1))
+    fi
+fi # NUMCOND
+ ;;
+esac
+N=$((N+1))
+
+# Test the modified umask option, in particular if umask with first address
+# (SHELL) does not affect umask of second address, i.e. original umask is
+# recovered
+NAME=UMASK_ON_SYSTEM
+case "$TESTS" in
+*%$N%*|*%functions%*|*%shell%*|*%umask%*|*%socket%*|*%$NAME%*)
+TEST="$NAME: test restore after SHELL with umask option"
+# Run Socat with first address SHELL:"cat >file" with modified umask,
+# and second address SYSTEM (shell) with umask command.
+# Check if the file is created with modified umask but shell has original umask
+if ! eval $NUMCOND; then :;
+elif ! F=$(testfeats SHELL SYSTEM); then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Feature $F not configured in $SOCAT${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
+elif ! A=$(testaddrs SHELL SYSTEM); then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Address $A not available in $SOCAT${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
+elif ! o=$(testoptions umask) >/dev/null; then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Option $o not available in $SOCAT${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
+else
+    tf="$td/test$N.stdout"
+    te="$td/test$N.stderr"
+    tc="$td/test$N.creat"
+    tdiff="$td/test$N.diff"
+    tdebug="$td/test$N.debug"
+    oumask=$(umask)
+    # Construct a temp umask differing from original umask
+    case oumask in
+	*066) tumask=0026 ;;
+	*)    tumask=0066 ;;
+    esac
+    CMD0="$TRACE $SOCAT $opts -U SHELL:\"cat\ >$tc\",umask=$tumask SYSTEM:umask"
+    printf "test $F_n $TEST... " $N
+    eval "$CMD0" >/dev/null 2>"${te}0"
+    rc0=$?
+    tperms=$(fileperms $tc)
+    case $tperms in
+	0*) ;;
+	*) tperms=0$tperms ;;
+    esac
+    echo "Original umask:  $oumask" >>$tdebug
+    echo "Temporary umask: $tumask" >>$tdebug
+    echo "Created umask:   $tperms" >>$tdebug
+    if [ "$rc0" -ne 0 ]; then
+	$PRINTF "$FAILED\n"
+	echo "$CMD0 &"
+	cat "${te}0" >&2
+	numFAIL=$((numFAIL+1))
+	listFAIL="$listFAIL $N"
+	namesFAIL="$namesFAIL $NAME"
+    elif [ $((tumask + tperms - 0666)) -ne 0 ]; then
+	$PRINTF "$FAILED (umask failed)\n"
+	echo "$CMD0 &"
+	cat "${te}0" >&2
+	numFAIL=$((numFAIL+1))
+	listFAIL="$listFAIL $N"
+	namesFAIL="$namesFAIL $NAME"
+    elif ! echo "$oumask" |diff "$tc" - >$tdiff; then
+	$PRINTF "$FAILED (bad umask)\n"
+	echo "$CMD0 &"
+	cat "${te}0" >&2
+	numFAIL=$((numFAIL+1))
+	listFAIL="$listFAIL $N"
+	namesFAIL="$namesFAIL $NAME"
+    else
+	$PRINTF "$OK\n"
+	if [ "$VERBOSE" ]; then echo "$CMD0 &"; fi
+	if [ "$DEBUG" ];   then cat "${te}0" >&2; fi
+	numOK=$((numOK+1))
+    fi
 fi # NUMCOND
  ;;
 esac

xio-named.c

@@ -21,7 +21,6 @@ const struct optdesc opt_unlink      = { "unlink",      NULL, OPT_UNLINK,      G
 const struct optdesc opt_unlink_early= { "unlink-early",NULL, OPT_UNLINK_EARLY,GROUP_NAMED, PH_EARLY,    TYPE_BOOL, OFUNC_SPEC };
 const struct optdesc opt_unlink_late = { "unlink-late", NULL, OPT_UNLINK_LATE, GROUP_NAMED, PH_PASTOPEN, TYPE_BOOL, OFUNC_SPEC };
 const struct optdesc opt_unlink_close  = { "unlink-close", NULL, OPT_UNLINK_CLOSE, GROUP_NAMED, PH_LATE,  TYPE_BOOL, OFUNC_SPEC };
-const struct optdesc opt_umask       = { "umask",       NULL, OPT_UMASK,       GROUP_NAMED, PH_EARLY,  TYPE_MODET, OFUNC_SPEC };
 #endif /* WITH_NAMED */
 
 /* applies to filesystem entry all options belonging to phase */
@@ -71,12 +70,6 @@ int applyopts_named(const char *filename, struct opt *opts, unsigned int phase)
 	    }
 	 }
 	 break;
-      case OPT_UMASK:
-	 if (Umask(opt->value.u_modet) < 0) {
-	    /* linux docu says it always succeeds, but who believes it? */
-	    Error2("umask("F_mode"): %s", opt->value.u_modet, strerror(errno));
-	 }
-	 break;
       default: Error1("applyopts_named(): option \"%s\" not implemented",
 		      opt->desc->defname);
 	 break;

xio-named.h

@@ -14,7 +14,6 @@ extern const struct optdesc opt_unlink;
 extern const struct optdesc opt_unlink_early;
 extern const struct optdesc opt_unlink_late;
 extern const struct optdesc opt_unlink_close;
-extern const struct optdesc opt_umask;
 
 extern int
    applyopts_named(const char *filename, struct opt *opts, unsigned int phase);

xiolayer.c

@@ -24,3 +24,4 @@ const struct optdesc opt_intervall = { "interval",  NULL, OPT_INTERVALL, GROUP_R
 const struct optdesc opt_retry     = { "retry",     NULL, OPT_RETRY,     GROUP_RETRY, PH_INIT, TYPE_UINT, OFUNC_EXT, XIO_OFFSETOF(retry),     XIO_SIZEOF(retry) };
 #endif
 
+const struct optdesc opt_umask       = { "umask",       NULL, OPT_UMASK,       GROUP_ADDR, PH_INIT,  TYPE_MODET, OFUNC_SPEC };

xiolayer.h

@@ -15,5 +15,7 @@ extern const struct optdesc opt_escape;
 extern const struct optdesc opt_forever;
 extern const struct optdesc opt_intervall;
 extern const struct optdesc opt_retry;
+extern const struct optdesc opt_umask;
+extern const struct optdesc opt_un_umask;
 
 #endif /* !defined(__xiolayer_h_included) */

xioopen.c

@@ -621,6 +621,9 @@ int xioopen_single(xiofile_t *xfd, int xioflags) {
    struct single *sfd = &xfd->stream;
    const struct addrdesc *addrdesc;
    const char *modetext[4] = { "none", "read-only", "write-only", "read-write" } ;
+   /* Values to be saved until xioopen() is finished */
+   bool have_umask = false;
+   mode_t orig_umask, tmp_umask;
    int result;
    /* Values to be saved until xioopen() is finished */
 #if WITH_RESOLVE && HAVE_RESOLV_H
@@ -633,6 +636,8 @@ int xioopen_single(xiofile_t *xfd, int xioflags) {
 #endif
    int rc;
 
+   /* Apply "temporary" process properties, save value for later restore */
+
    if (applyopts_single(sfd, sfd->opts, PH_OFFSET) < 0)
       return -1;
 
@@ -676,10 +681,23 @@ int xioopen_single(xiofile_t *xfd, int xioflags) {
    }
    xfd->stream.flags     &= (~XIO_ACCMODE);
    xfd->stream.flags     |= (xioflags & XIO_ACCMODE);
+
+   if (retropt_mode(xfd->stream.opts, OPT_UMASK, &tmp_umask) >= 0) {
+      Info1("changing umask to 0%3o", tmp_umask);
+      orig_umask = Umask(tmp_umask);
+      have_umask = true;
+   }
+
    result = (*addrdesc->func)(xfd->stream.argc, xfd->stream.argv,
 			      xfd->stream.opts, xioflags, xfd,
 			      addrdesc);
 
+   /* Restore process properties */
+   if (have_umask) {
+      Info1("restoring umask to 0%3o", orig_umask);
+      Umask(orig_umask);
+   }
+
 #if WITH_RESOLVE && HAVE_RESOLV_H
    if (do_res)
       xio_res_restore(&save_res);

xioopts.c

@@ -2074,7 +2074,7 @@ int parseopts_table(const char **a, groups_t groups, struct opt **opts,
       }
 
       if (!(ent->desc->group & groups) && !(ent->desc->group & GROUP_ANY) &&
-	  !xioopts_ignoregroups) {
+	  (ent->desc->group != GROUP_ADDR) && !xioopts_ignoregroups) {
 	 Error1("parseopts_table(): option \"%s\" not supported with this address type",
 		token /*a0*/);
 	 Info2("parseopts_table()  groups="F_groups_t", ent->group="F_groups_t,

xioopts.h

@@ -148,6 +148,7 @@ enum e_func {
 /* keep consistent with xiohelp.c:addressgroupnames[] ! */
 /* a dummy group */
 #define GROUP_NONE	0x00000000
+#define GROUP_ADDR	0x00000000 	/* options that apply to all addresses */
 
 #define GROUP_FD	0x00000001	/* everything applyable to a fd */
 #define GROUP_FIFO	0x00000002
@@ -862,6 +863,7 @@ enum e_optcode {
    OPT_UNLINK_CLOSE,
    OPT_UNLINK_EARLY,
    OPT_UNLINK_LATE,
+   OPT_UN_UMASK,
    OPT_USER,
    OPT_USER_EARLY,
    OPT_USER_LATE,