Capsicum support for dd(1)

Adds Capsicum sandboxing to dd utility.

Submitted by:	Pawel Biernacki <pawel.biernacki@gmail.com>
Reviewed by:	allanjude, emaste, oshogbo
Approved by:	oshogbo
Sponsored by:	Mysterious Code Ltd.
Differential Revision:	https://reviews.freebsd.org/D8543
This commit is contained in:
Bartek Rutkowski 2016-11-18 21:09:57 +00:00
parent 454d904a0e
commit 947b83c090
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=308810

View File

@ -48,10 +48,13 @@ __FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/conf.h>
#include <sys/capsicum.h>
#include <sys/disklabel.h>
#include <sys/filio.h>
#include <sys/mtio.h>
#include <assert.h>
#include <capsicum_helpers.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
@ -92,6 +95,10 @@ main(int argc __unused, char *argv[])
jcl(argv);
setup();
caph_cache_catpages();
if (cap_enter() == -1 && errno != ENOSYS)
err(1, "unable to enter capability mode");
(void)signal(SIGINFO, siginfo_handler);
(void)signal(SIGINT, terminate);
@ -125,6 +132,8 @@ static void
setup(void)
{
u_int cnt;
cap_rights_t rights;
unsigned long cmds[] = { FIODTYPE, MTIOCTOP };
if (in.name == NULL) {
in.name = "stdin";
@ -133,13 +142,20 @@ setup(void)
in.fd = open(in.name, O_RDONLY, 0);
if (in.fd == -1)
err(1, "%s", in.name);
if (caph_limit_stdin() == -1)
err(1, "unable to limit capability rights");
}
getfdtype(&in);
cap_rights_init(&rights, CAP_READ, CAP_SEEK);
if (cap_rights_limit(in.fd, &rights) == -1 && errno != ENOSYS)
err(1, "unable to limit capability rights");
if (files_cnt > 1 && !(in.flags & ISTAPE))
errx(1, "files is not supported for non-tape devices");
cap_rights_set(&rights, CAP_WRITE, CAP_FTRUNCATE, CAP_IOCTL);
if (out.name == NULL) {
/* No way to check for read access here. */
out.fd = STDOUT_FILENO;
@ -156,13 +172,27 @@ setup(void)
if (out.fd == -1) {
out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE);
out.flags |= NOREAD;
cap_rights_clear(&rights, CAP_READ);
}
if (out.fd == -1)
err(1, "%s", out.name);
if (caph_limit_stdout() == -1)
err(1, "unable to limit capability rights");
}
getfdtype(&out);
if (cap_rights_limit(out.fd, &rights) == -1 && errno != ENOSYS)
err(1, "unable to limit capability rights");
if (cap_ioctls_limit(out.fd, cmds, nitems(cmds)) == -1 &&
errno != ENOSYS)
err(1, "unable to limit capability rights");
if (in.fd != STDERR_FILENO && out.fd != STDERR_FILENO) {
if (caph_limit_stderr() == -1)
err(1, "unable to limit capability rights");
}
/*
* Allocate space for the input and output buffers. If not doing
* record oriented I/O, only need a single buffer.