1*f6217f89SApple OSS Distributions #include <stdio.h> 2*f6217f89SApple OSS Distributions #include <fcntl.h> 3*f6217f89SApple OSS Distributions #include <util.h> 4*f6217f89SApple OSS Distributions #include <unistd.h> 5*f6217f89SApple OSS Distributions #include <sys/types.h> 6*f6217f89SApple OSS Distributions #include <sys/stat.h> 7*f6217f89SApple OSS Distributions #include <darwintest.h> 8*f6217f89SApple OSS Distributions 9*f6217f89SApple OSS Distributions T_DECL(dev_zero, 10*f6217f89SApple OSS Distributions "test reading from /dev/zero", 11*f6217f89SApple OSS Distributions T_META_ASROOT(false)) 12*f6217f89SApple OSS Distributions { 13*f6217f89SApple OSS Distributions int dev = opendev("/dev/zero", O_RDONLY, 0, NULL); 14*f6217f89SApple OSS Distributions char buffer[100]; 15*f6217f89SApple OSS Distributions 16*f6217f89SApple OSS Distributions for (int i = 0; i < 100; i++) { 17*f6217f89SApple OSS Distributions buffer[i] = 0xff; 18*f6217f89SApple OSS Distributions } 19*f6217f89SApple OSS Distributions 20*f6217f89SApple OSS Distributions int rd_sz = read(dev, buffer, sizeof(buffer)); 21*f6217f89SApple OSS Distributions 22*f6217f89SApple OSS Distributions T_EXPECT_EQ(rd_sz, 100, "read from /dev/zero failed"); 23*f6217f89SApple OSS Distributions 24*f6217f89SApple OSS Distributions for (int i = 0; i < 100; i++) { 25*f6217f89SApple OSS Distributions if (buffer[i]) { 26*f6217f89SApple OSS Distributions T_FAIL("Unexpected non-zero character read from /dev/zero"); 27*f6217f89SApple OSS Distributions } 28*f6217f89SApple OSS Distributions } 29*f6217f89SApple OSS Distributions 30*f6217f89SApple OSS Distributions close(dev); 31*f6217f89SApple OSS Distributions } 32*f6217f89SApple OSS Distributions 33*f6217f89SApple OSS Distributions T_DECL(dev_zero_permissions, 34*f6217f89SApple OSS Distributions "ensure /dev/zero's permissions can't be updated", 35*f6217f89SApple OSS Distributions T_META_ASROOT(true)) 36*f6217f89SApple OSS Distributions { 37*f6217f89SApple OSS Distributions struct stat sb = {0}; 38*f6217f89SApple OSS Distributions const char *dev = "/dev/zero"; 39*f6217f89SApple OSS Distributions int ret = 0; 40*f6217f89SApple OSS Distributions 41*f6217f89SApple OSS Distributions ret = stat(dev, &sb); 42*f6217f89SApple OSS Distributions T_ASSERT_POSIX_SUCCESS(ret, "stat /dev/zero"); 43*f6217f89SApple OSS Distributions T_ASSERT_TRUE(sb.st_mode & S_IWOTH, "/dev/zero world writable"); 44*f6217f89SApple OSS Distributions 45*f6217f89SApple OSS Distributions ret = chmod(dev, 0664); 46*f6217f89SApple OSS Distributions T_ASSERT_POSIX_FAILURE(ret, EPERM, "chmod /dev/zero should fail w/ EPERM"); 47*f6217f89SApple OSS Distributions 48*f6217f89SApple OSS Distributions ret = stat(dev, &sb); 49*f6217f89SApple OSS Distributions T_ASSERT_POSIX_SUCCESS(ret, "stat /dev/zero"); 50*f6217f89SApple OSS Distributions T_ASSERT_TRUE(sb.st_mode & S_IWOTH, "/dev/zero still world writable"); 51*f6217f89SApple OSS Distributions } 52