MFC: r274960 (slightly modified)

Limit descriptors and enter capability mode.  Since the header was renamed in HEAD, this
commit includes sys/capability.h.

Differential:	D1009
Reviewed by:	jonathan, pjd
Relnotes:	yes
This commit is contained in:
brueffer 2014-12-19 23:18:22 +00:00
parent 98ddab22ac
commit f419d174a9

View File

@ -29,12 +29,15 @@
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/capability.h>
#include <sys/elf32.h>
#include <sys/elf64.h>
#include <sys/endian.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stddef.h>
@ -467,6 +470,7 @@ elf_get_shstrndx(Elf32_Ehdr *e, void *sh)
int
main(int ac, char **av)
{
cap_rights_t rights;
u_int64_t phoff;
u_int64_t shoff;
u_int64_t phentsize;
@ -527,6 +531,9 @@ main(int ac, char **av)
case 'w':
if ((out = fopen(optarg, "w")) == NULL)
err(1, "%s", optarg);
cap_rights_init(&rights, CAP_FSTAT, CAP_WRITE);
if (cap_rights_limit(fileno(out), &rights) < 0 && errno != ENOSYS)
err(1, "unable to limit rights for %s", optarg);
break;
case '?':
default:
@ -539,6 +546,17 @@ main(int ac, char **av)
if ((fd = open(*av, O_RDONLY)) < 0 ||
fstat(fd, &sb) < 0)
err(1, "%s", *av);
cap_rights_init(&rights, CAP_MMAP_R);
if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS)
err(1, "unable to limit rights for %s", *av);
close(STDIN_FILENO);
cap_rights_init(&rights, CAP_WRITE);
if (cap_rights_limit(STDOUT_FILENO, &rights) < 0 && errno != ENOSYS)
err(1, "unable to limit rights for stdout");
if (cap_rights_limit(STDERR_FILENO, &rights) < 0 && errno != ENOSYS)
err(1, "unable to limit rights for stderr");
if (cap_enter() < 0 && errno != ENOSYS)
err(1, "unable to enter capability mode");
e = mmap(NULL, sb.st_size, PROT_READ, MAP_SHARED, fd, 0);
if (e == MAP_FAILED)
err(1, NULL);