diff options
Diffstat (limited to 'tools/regression/priv/priv_vfs_generation.c')
-rw-r--r-- | tools/regression/priv/priv_vfs_generation.c | 115 |
1 files changed, 61 insertions, 54 deletions
diff --git a/tools/regression/priv/priv_vfs_generation.c b/tools/regression/priv/priv_vfs_generation.c index 2ccca79..0ac58c5 100644 --- a/tools/regression/priv/priv_vfs_generation.c +++ b/tools/regression/priv/priv_vfs_generation.c @@ -1,5 +1,6 @@ /*- * Copyright (c) 2006 nCircle Network Security, Inc. + * Copyright (c) 2007 Robert N. M. Watson * All rights reserved. * * This software was developed by Robert N. M. Watson for the TrustedBSD @@ -33,8 +34,8 @@ * Confirm that a generation number isn't returned by stat() when not running * with privilege. In order to differentiate between a generation of 0 and * a generation not being returned, we have to create a temporary file known - * to have a non-0 generation. We try up to 10 times, and then give up, - * which is non-ideal, but better than not testing for a problem. + * to have a non-0 generation. We try up to MAX_TRIES times, and then give + * up, which is non-ideal, but better than not testing for a problem. */ #include <sys/stat.h> @@ -46,68 +47,74 @@ #include "main.h" -/* - * Can't use setup_file() since the resulting file needs to have specific - * properties. - */ -void -priv_vfs_generation(void) +static char fpath[1024]; +static int fpath_initialized; + +#define MAX_TRIES 100 + +int +priv_vfs_generation_setup(int asroot, int injail, struct test *test) { - char fpath[1024] = "/tmp/priv.XXXXXXXXXX"; struct stat sb; - int fd, i; - - assert_root(); + int i; /* - * Create a file with a non-0 generation number. Try ten times, - * which gives a high chance of succeeds, fail otherwise. Not ideal, - * since we can't distinguish the file having a generation of 0 from - * not being able to query it for access control reasons. The perils - * of an API that changes behavior based on lack of privilege rather - * than failing... + * The kernel zeros the generation number field when an unprivileged + * user stats a file. In order to distinguish the two cases, we + * therefore require a file that we know has a non-zero generation + * number. We try up to MAX_TRIES times and otherwise fail. */ - for (i = 0; i < 10; i++) { - fd = mkstemp(fpath); - if (fd < 0) - err(-1, "mkstemp"); - if (fstat(fd, &sb) < 0) { - warn("fstat(%s)", fpath); - close(fd); - goto out; + for (i = 0; i < MAX_TRIES; i++) { + setup_file("priv_vfs_generation_setup: fpath", fpath, + UID_ROOT, GID_WHEEL, 0644); + if (stat(fpath, &sb) < 0) { + warn("priv_vfs_generation_setup: fstat(%s)", fpath); + (void)unlink(fpath); + return (-1); + } + if (sb.st_gen != 0) { + fpath_initialized = 1; + return (0); } - if (sb.st_gen != 0) - break; - close(fd); - (void)unlink(fpath); - strcpy(fpath, "/tmp/generation.XXXXXXXXXX"); - fd = -1; } - if (fd == -1) - errx(-1, - "could not create file with non-0 generation as root"); - close(fd); + warnx("priv_vfs_generation_setup: unable to create gen file"); + return (-1); +} - /* - * We've already tested that fstat() works, but try stat() to be - * consistent between privileged and unprivileged tests. - */ - if (stat(fpath, &sb) < 0) { - warn("stat(%s) as root", fpath); - goto out; - } +void +priv_vfs_generation(int asroot, int injail, struct test *test) +{ + struct stat sb; + int error; - set_euid(UID_OTHER); + error = stat(fpath, &sb); + if (error < 0) + warn("priv_vfs_generation(asroot, injail) stat"); - if (stat(fpath, &sb) < 0) { - warn("stat(%s) as !root", fpath); - goto out; - } + if (sb.st_gen == 0) { + error = -1; + errno = EPERM; + } else + error = 0; + if (asroot && injail) + expect("priv_vfs_generation(asroot, injail)", error, -1, + EPERM); + if (asroot && !injail) + expect("priv_vfs_generation(asroot, !injail)", error, 0, 0); + if (!asroot && injail) + expect("priv_vfs_generation(!asroot, injail)", error, -1, + EPERM); + if (!asroot && !injail) + expect("priv_vfs_generation(!asroot, !injail)", error, -1, + EPERM); +} - if (sb.st_gen != 0) - warn("stat(%s) returned generation as !root", fpath); +void +priv_vfs_generation_cleanup(int asroot, int injail, struct test *test) +{ -out: - (void)seteuid(UID_ROOT); - (void)unlink(fpath); + if (fpath_initialized) { + (void)unlink(fpath); + fpath_initialized = 0; + } } |