1*043036a2SApple OSS Distributions #include <stdio.h> 2*043036a2SApple OSS Distributions #include <fcntl.h> 3*043036a2SApple OSS Distributions #include <util.h> 4*043036a2SApple OSS Distributions #include <unistd.h> 5*043036a2SApple OSS Distributions #include <sys/types.h> 6*043036a2SApple OSS Distributions #include <sys/stat.h> 7*043036a2SApple OSS Distributions #include <darwintest.h> 8*043036a2SApple OSS Distributions 9*043036a2SApple OSS Distributions T_DECL(dev_zero, 10*043036a2SApple OSS Distributions "test reading from /dev/zero", 11*043036a2SApple OSS Distributions T_META_ASROOT(false)) 12*043036a2SApple OSS Distributions { 13*043036a2SApple OSS Distributions int dev = opendev("/dev/zero", O_RDONLY, 0, NULL); 14*043036a2SApple OSS Distributions char buffer[100]; 15*043036a2SApple OSS Distributions 16*043036a2SApple OSS Distributions for (int i = 0; i < 100; i++) { 17*043036a2SApple OSS Distributions buffer[i] = 0xff; 18*043036a2SApple OSS Distributions } 19*043036a2SApple OSS Distributions 20*043036a2SApple OSS Distributions int rd_sz = read(dev, buffer, sizeof(buffer)); 21*043036a2SApple OSS Distributions 22*043036a2SApple OSS Distributions T_EXPECT_EQ(rd_sz, 100, "read from /dev/zero failed"); 23*043036a2SApple OSS Distributions 24*043036a2SApple OSS Distributions for (int i = 0; i < 100; i++) { 25*043036a2SApple OSS Distributions if (buffer[i]) { 26*043036a2SApple OSS Distributions T_FAIL("Unexpected non-zero character read from /dev/zero"); 27*043036a2SApple OSS Distributions } 28*043036a2SApple OSS Distributions } 29*043036a2SApple OSS Distributions 30*043036a2SApple OSS Distributions close(dev); 31*043036a2SApple OSS Distributions } 32*043036a2SApple OSS Distributions 33*043036a2SApple OSS Distributions T_DECL(dev_zero_permissions, 34*043036a2SApple OSS Distributions "ensure /dev/zero's permissions can't be updated", 35*043036a2SApple OSS Distributions T_META_ASROOT(true)) 36*043036a2SApple OSS Distributions { 37*043036a2SApple OSS Distributions struct stat sb = {0}; 38*043036a2SApple OSS Distributions const char *dev = "/dev/zero"; 39*043036a2SApple OSS Distributions int ret = 0; 40*043036a2SApple OSS Distributions 41*043036a2SApple OSS Distributions ret = stat(dev, &sb); 42*043036a2SApple OSS Distributions T_ASSERT_POSIX_SUCCESS(ret, "stat /dev/zero"); 43*043036a2SApple OSS Distributions T_ASSERT_TRUE(sb.st_mode & S_IWOTH, "/dev/zero world writable"); 44*043036a2SApple OSS Distributions 45*043036a2SApple OSS Distributions ret = chmod(dev, 0664); 46*043036a2SApple OSS Distributions T_ASSERT_POSIX_FAILURE(ret, EPERM, "chmod /dev/zero should fail w/ EPERM"); 47*043036a2SApple OSS Distributions 48*043036a2SApple OSS Distributions ret = stat(dev, &sb); 49*043036a2SApple OSS Distributions T_ASSERT_POSIX_SUCCESS(ret, "stat /dev/zero"); 50*043036a2SApple OSS Distributions T_ASSERT_TRUE(sb.st_mode & S_IWOTH, "/dev/zero still world writable"); 51*043036a2SApple OSS Distributions } 52