orscmd: add minimal getcap and setcap tools
These are mostly intended for debugging and for emergency repairs.
Optimized for minimal code size and dependencies, not for usability.
Change-Id: I671850a03151dd716c715f953f0b2bc8dbacffe7
diff --git a/orscmd/orscmd.cpp b/orscmd/orscmd.cpp
index 53c5bc0..c008450 100644
--- a/orscmd/orscmd.cpp
+++ b/orscmd/orscmd.cpp
@@ -13,12 +13,20 @@
along with TWRP. If not, see <http://www.gnu.org/licenses/>.
*/
+#define __STDC_FORMAT_MACROS 1
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
+#include <errno.h>
+#include <inttypes.h>
+
+// for setcap and getcap
+#include <sys/capability.h>
+#include <sys/xattr.h>
+#include <linux/xattr.h>
#include "orscmd.h"
#include "../variables.h"
@@ -44,6 +52,45 @@
printf("\nSee more documentation at http://teamw.in/openrecoveryscript\n");
}
+int do_setcap(const char* filename, const char* capabilities)
+{
+ uint64_t caps;
+ if (sscanf(capabilities, "%" SCNi64, &caps) != 1)
+ {
+ printf("setcap: invalid capabilities \"%s\"\n", filename);
+ return 1;
+ }
+ struct vfs_cap_data cap_data;
+ memset(&cap_data, 0, sizeof(cap_data));
+ cap_data.magic_etc = VFS_CAP_REVISION | VFS_CAP_FLAGS_EFFECTIVE;
+ cap_data.data[0].permitted = (uint32_t) (caps & 0xffffffff);
+ cap_data.data[0].inheritable = 0;
+ cap_data.data[1].permitted = (uint32_t) (caps >> 32);
+ cap_data.data[1].inheritable = 0;
+ if (setxattr(filename, XATTR_NAME_CAPS, &cap_data, sizeof(cap_data), 0) < 0) {
+ printf("setcap of %s to %" PRIx64 " failed: %s\n",
+ filename, caps, strerror(errno));
+ return 1;
+ }
+ return 0;
+}
+
+int do_getcap(const char* filename)
+{
+ struct vfs_cap_data cap_data;
+ memset(&cap_data, 0, sizeof(cap_data));
+ int rc = getxattr(filename, XATTR_NAME_CAPS, &cap_data, sizeof(vfs_cap_data));
+ if (rc > 0)
+ {
+ uint64_t caps = (uint64_t) cap_data.data[1].permitted << 32 | cap_data.data[0].permitted;
+ printf("0x%" PRIx64 "\n", caps);
+ }
+ else
+ printf("getcap of %s failed: %s\n", filename, strerror(errno));
+
+ return rc > 0;
+}
+
int main(int argc, char **argv) {
int read_fd, write_fd, index;
char command[1024], result[512];
@@ -57,6 +104,25 @@
return 0;
}
+ if (strcmp(argv[1], "setcap") == 0) {
+ if (argc != 4)
+ {
+ printf("Usage: setcap filename capabilities\n\n"
+ "capabilities must be specified as a number. Prefix with 0x for hexadecimal.\n");
+ return 1;
+ }
+ return do_setcap(argv[2], argv[3]);
+ }
+
+ if (strcmp(argv[1], "getcap") == 0) {
+ if (argc != 3)
+ {
+ printf("Usage: getcap filename\n");
+ return 1;
+ }
+ return do_getcap(argv[2]);
+ }
+
sprintf(command, "%s", argv[1]);
for (index = 2; index < argc; index++) {
sprintf(command, "%s %s", command, argv[index]);