openssh/openssh-7.2p2-sftp_force_permissions.patch

# HG changeset patch
# Parent  7b45c4f3fef6836db00c5b198736cce17290c5cd
additional option for sftp-server to force file mode for new files
FATE#312774
http://lists.mindrot.org/pipermail/openssh-unix-dev/2010-November/029044.html
http://marc.info/?l=openssh-unix-dev&m=128896838930893

diff --git a/openssh-7.2p2/sftp-server.8 b/openssh-7.2p2/sftp-server.8
--- a/openssh-7.2p2/sftp-server.8
+++ b/openssh-7.2p2/sftp-server.8
@@ -33,16 +33,17 @@
 .Bk -words
 .Op Fl ehR
 .Op Fl d Ar start_directory
 .Op Fl f Ar log_facility
 .Op Fl l Ar log_level
 .Op Fl P Ar blacklisted_requests
 .Op Fl p Ar whitelisted_requests
 .Op Fl u Ar umask
+.Op Fl m Ar force_file_permissions
 .Ek
 .Nm
 .Fl Q Ar protocol_feature
 .Sh DESCRIPTION
 .Nm
 is a program that speaks the server side of SFTP protocol
 to stdout and expects client requests from stdin.
 .Nm
@@ -133,16 +134,20 @@ Places this instance of
 into a read-only mode.
 Attempts to open files for writing, as well as other operations that change
 the state of the filesystem, will be denied.
 .It Fl u Ar umask
 Sets an explicit
 .Xr umask 2
 to be applied to newly-created files and directories, instead of the
 user's default mask.
+.It Fl m Ar force_file_permissions
+Sets explicit file permissions to be applied to newly-created files instead
+of the default or client requested mode.  Numeric values include:
+777, 755, 750, 666, 644, 640, etc.  Option -u is ineffective if -m is set.
 .El
 .Pp
 On some systems,
 .Nm
 must be able to access
 .Pa /dev/log
 for logging to work, and use of
 .Nm
diff --git a/openssh-7.2p2/sftp-server.c b/openssh-7.2p2/sftp-server.c
--- a/openssh-7.2p2/sftp-server.c
+++ b/openssh-7.2p2/sftp-server.c
@@ -73,16 +73,20 @@ static u_int version;
 static int init_done;
 
 /* Disable writes */
 static int readonly;
 
 /* Requests that are allowed/denied */
 static char *request_whitelist, *request_blacklist;
 
+/* Force file permissions */
+int permforce = 0;
+long permforcemode;
+
 /* portable attributes, etc. */
 typedef struct Stat Stat;
 
 struct Stat {
 	char *name;
 	char *long_name;
 	Attrib attrib;
 };
@@ -687,16 +691,20 @@ process_open(u_int32_t id)
 	if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 ||
 	    (r = sshbuf_get_u32(iqueue, &pflags)) != 0 || /* portable flags */
 	    (r = decode_attrib(iqueue, &a)) != 0)
 		fatal("%s: buffer error: %s", __func__, ssh_err(r));
 
 	debug3("request %u: open flags %d", id, pflags);
 	flags = flags_from_portable(pflags);
 	mode = (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a.perm : 0666;
+	if (permforce == 1) {
+		mode = permforcemode;
+		(void)umask(0); /* so umask does not interfere */
+	}
 	logit("open \"%s\" flags %s mode 0%o",
 	    name, string_from_portable(pflags), mode);
 	if (readonly &&
 	    ((flags & O_ACCMODE) == O_WRONLY ||
 	    (flags & O_ACCMODE) == O_RDWR)) {
 		verbose("Refusing open request in read-only mode");
 		status = SSH2_FX_PERMISSION_DENIED;
 	} else {
@@ -1489,17 +1497,18 @@ sftp_server_cleanup_exit(int i)
 static void
 sftp_server_usage(void)
 {
 	extern char *__progname;
 
 	fprintf(stderr,
 	    "usage: %s [-ehR] [-d start_directory] [-f log_facility] "
 	    "[-l log_level]\n\t[-P blacklisted_requests] "
-	    "[-p whitelisted_requests] [-u umask]\n"
+	    "[-p whitelisted_requests] [-u umask]\n\t"
+	    "[-m force_file_permissions]\n"
 	    "       %s -Q protocol_feature\n",
 	    __progname, __progname);
 	exit(1);
 }
 
 int
 sftp_server_main(int argc, char **argv, struct passwd *user_pw)
 {
@@ -1515,17 +1524,17 @@ sftp_server_main(int argc, char **argv, 
 
 	ssh_malloc_init();	/* must be called before any mallocs */
 	__progname = ssh_get_progname(argv[0]);
 	log_init(__progname, log_level, log_facility, log_stderr);
 
 	pw = pwcopy(user_pw);
 
 	while (!skipargs && (ch = getopt(argc, argv,
-	    "d:f:l:P:p:Q:u:cehR")) != -1) {
+	    "d:f:l:P:p:Q:u:m:cehR")) != -1) {
 		switch (ch) {
 		case 'Q':
 			if (strcasecmp(optarg, "requests") != 0) {
 				fprintf(stderr, "Invalid query type\n");
 				exit(1);
 			}
 			for (i = 0; handlers[i].handler != NULL; i++)
 				printf("%s\n", handlers[i].name);
@@ -1575,16 +1584,23 @@ sftp_server_main(int argc, char **argv, 
 		case 'u':
 			errno = 0;
 			mask = strtol(optarg, &cp, 8);
 			if (mask < 0 || mask > 0777 || *cp != '\0' ||
 			    cp == optarg || (mask == 0 && errno != 0))
 				fatal("Invalid umask \"%s\"", optarg);
 			(void)umask((mode_t)mask);
 			break;
+		case 'm':
+			permforce = 1;
+			permforcemode = strtol(optarg, &cp, 8);
+			if (permforcemode < 0 || permforcemode > 0777 || *cp != '\0' ||
+				cp == optarg || (permforcemode == 0 && errno != 0))
+				fatal("Invalid umask \"%s\"", optarg);
+			break;
 		case 'h':
 		default:
 			sftp_server_usage();
 		}
 	}
 
 	log_init(__progname, log_level, log_facility, log_stderr);