commit - cedef5b09c13d8fac119a7ee5595ee253c2a37b4
commit + 4d9d3093d48025a1a66c125f7878a094cf2c9d10
blob - dd6e6d4684904bc10aeb05d7304a6484d4aed081
blob + 44dae1b06334c739d2a92684c492dda12884a2f5
--- Makefile
+++ Makefile
TITAN_SRCS = titan.c iri.c log.c utf8.c
TITAN_OBJS = ${TITAN_SRCS:.c=.o} ${COBJS}
-SRCS = gmid.h log.h parse.y proc.h \
+SRCS = gmid.h landlock_shim.h log.h parse.y proc.h \
${GMID_SRCS} ${GEMEXP_SRCS} ${GG_SRCS} ${TITAN_SRCS}
DISTNAME = gmid-${VERSION}
DISTFILES = .cirrus.yml .dockerignore .gitignore ChangeLog LICENSE \
Makefile README.md config.c configure configure.local.example \
crypto.c dirs.c fcgi.c ge.c gemexp.1 gg.1 gg.c gmid.8 gmid.c \
- gmid.conf.5 gmid.h iri.c iri.h log.c log.h logger.c mime.c \
- parse.y proc.c proc.h proxy.c puny.c sandbox.c server.c \
- titan.1 titan.c utf8.c utils.c y.tab.c
+ gmid.conf.5 gmid.h iri.c iri.h landlock_shim.h log.c log.h \
+ logger.c mime.c parse.y proc.c proc.h proxy.c puny.c \
+ sandbox.c server.c titan.1 titan.c utf8.c utils.c y.tab.c
release:
sed -i -e '/^RELEASE=/s/no/yes' configure
blob - c77f13ca7fb5f9eb8e00f08d258e0ac3d831af1a
blob + cedf5957d6da765370b832e0ba9816a7d200ab8d
--- configure
+++ configure
runtest getdtablesize GETDTABLESIZE || true
runtest getprogname GETPROGNAME || true
runtest imsg IMSG "" -lutil libimsg || true
+runtest landlock LANDLOCK || true
runtest libevent LIBEVENT "" -levent libevent_core|| true
runtest memmem MEMMEM -D_GNU_SOURCE || true
runtest openssl OPENSSL "" '-lcrypto -lssl' 'libcrypto libssl' || true
#define VERSION "${VERSION}"
#define DISABLE_SANDBOX ${DISABLE_SANDBOX}
+#define HAVE_LANDLOCK ${HAVE_LANDLOCK}
__HEREDOC__
blob - d2a1dfa7860a0922228e753a972ad2787d2ba1fd
blob + b9ff6ec8c2b68c279ee4029198c208292a05a314
--- have/Makefile
+++ have/Makefile
getentropy.c \
getprogname.c \
imsg.c \
+ landlock.c \
libevent.c \
libevent2.c \
libtls.c \
blob - /dev/null
blob + 6548e88e5719dd622485dfda0015ac0c0e51f597 (mode 644)
--- /dev/null
+++ have/landlock.c
+/*
+ * Copyright (c) 2023 Omar Polo <op@omarpolo.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <linux/landlock.h>
+#include <sys/prctl.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+
+#ifndef landlock_create_ruleset
+static inline int
+landlock_create_ruleset(const struct landlock_ruleset_attr *attr, size_t size,
+ __u32 flags)
+{
+ return syscall(__NR_landlock_create_ruleset, attr, size, flags);
+}
+#endif
+
+int
+main(void)
+{
+ int rfd;
+ const struct landlock_ruleset_attr rsattr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE |
+ LANDLOCK_ACCESS_FS_READ_DIR
+ };
+
+ rfd = landlock_create_ruleset(&rsattr, sizeof(rsattr), 0);
+ return rfd == -1;
+}
blob - 0e7e4ada9d08a1068809c56aa8cfb75d00b8f3e1
blob + 0e171106443a77665af287a46178857600fe07d5
--- sandbox.c
+++ sandbox.c
/*
* Copyright (c) 2021, 2023 Omar Polo <op@omarpolo.com>
+ * Copyright (c) 2022 Claudio Jeker <claudio@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
fatal("pledge");
}
+#elif HAVE_LANDLOCK
+
+#include <linux/landlock.h>
+
+#include <sys/prctl.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+
+#include <errno.h>
+
+/*
+ * What's the deal with landlock? While distro with linux >= 5.13
+ * have the struct declarations, libc wrappers are missing. The
+ * sample landlock code provided by the authors includes these "shims"
+ * in their example for the landlock API until libc provides them.
+ */
+
+#ifndef landlock_create_ruleset
+static inline int
+landlock_create_ruleset(const struct landlock_ruleset_attr *attr, size_t size,
+ __u32 flags)
+{
+ return syscall(__NR_landlock_create_ruleset, attr, size, flags);
+}
+#endif
+
+#ifndef landlock_add_rule
+static inline int
+landlock_add_rule(int ruleset_fd, enum landlock_rule_type type,
+ const void *attr, __u32 flags)
+{
+ return syscall(__NR_landlock_add_rule, ruleset_fd, type, attr, flags);
+}
+#endif
+
+#ifndef landlock_restrict_self
+static inline int
+landlock_restrict_self(int ruleset_fd, __u32 flags)
+{
+ return syscall(__NR_landlock_restrict_self, ruleset_fd, flags);
+}
+#endif
+
+/*
+ * Maybe we should ship with a full copy of the linux headers because
+ * you never know...
+ */
+
+#ifndef LANDLOCK_ACCESS_FS_REFER
+#define LANDLOCK_ACCESS_FS_REFER (1ULL << 13)
+#endif
+
+#ifndef LANDLOCK_ACCESS_FS_TRUNCATE
+#define LANDLOCK_ACCESS_FS_TRUNCATE (1ULL << 14)
+#endif
+
+static int landlock_state;
+static int landlock_fd;
+
+/*
+ * Initialize landlock, which is stupidly complicated.
+ */
+static int
+landlock_init(void)
+{
+ struct landlock_ruleset_attr rattr = {
+ /*
+ * List all capabilities currently defined by landlock.
+ * Failure in doing so will implicitly allow those actions
+ * (i.e. omitting READ_FILE will allow to read _any_ file.)
+ */
+ .handled_access_fs =
+ LANDLOCK_ACCESS_FS_EXECUTE |
+ LANDLOCK_ACCESS_FS_READ_FILE |
+ LANDLOCK_ACCESS_FS_READ_DIR |
+ LANDLOCK_ACCESS_FS_WRITE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_MAKE_CHAR |
+ LANDLOCK_ACCESS_FS_MAKE_DIR |
+ LANDLOCK_ACCESS_FS_MAKE_REG |
+ LANDLOCK_ACCESS_FS_MAKE_SOCK |
+ LANDLOCK_ACCESS_FS_MAKE_FIFO |
+ LANDLOCK_ACCESS_FS_MAKE_BLOCK |
+ LANDLOCK_ACCESS_FS_MAKE_SYM |
+ LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_TRUNCATE,
+ };
+ int fd, abi, saved_errno;
+
+ if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) == -1)
+ return -1;
+
+ abi = landlock_create_ruleset(NULL, 0, LANDLOCK_CREATE_RULESET_VERSION);
+ if (abi == -1)
+ return -1;
+ if (abi < 2)
+ rattr.handled_access_fs &= ~LANDLOCK_ACCESS_FS_REFER;
+ if (abi < 3)
+ rattr.handled_access_fs &= ~LANDLOCK_ACCESS_FS_TRUNCATE;
+
+ landlock_state = 1;
+ return landlock_create_ruleset(&rattr, sizeof(rattr), 0);
+}
+
+static int
+landlock_lock(void)
+{
+ int saved_errno;
+
+ if (landlock_restrict_self(landlock_fd, 0)) {
+ saved_errno = errno;
+ close(landlock_fd);
+ errno = saved_errno;
+ landlock_state = -1;
+ return -1;
+ }
+
+ landlock_state = 2;
+ close(landlock_fd);
+ return 0;
+}
+
+static int
+landlock_unveil(const char *path, const char *permissions)
+{
+ struct landlock_path_beneath_attr lpba;
+ int fd, saved_errno;
+
+ if (landlock_state == 0) {
+ if ((landlock_fd = landlock_init()) == -1) {
+ landlock_state = -1;
+ /* this kernel doesn't have landlock built in */
+ if (errno == ENOSYS || errno == EOPNOTSUPP)
+ return 0;
+ return -1;
+ }
+ }
+
+ /* no landlock available */
+ if (landlock_state == -1)
+ return 0;
+
+ if (path == NULL && permissions == NULL)
+ return landlock_lock();
+
+ if (path == NULL || permissions == NULL || landlock_state != 1) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (!strcmp(permissions, "r")) {
+ fd = open(path, O_PATH | O_CLOEXEC);
+ if (fd == -1)
+ return -1;
+ lpba = (struct landlock_path_beneath_attr){
+ .allowed_access =
+ LANDLOCK_ACCESS_FS_READ_FILE |
+ LANDLOCK_ACCESS_FS_READ_DIR,
+ .parent_fd = fd,
+ };
+ if (landlock_add_rule(landlock_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &lpba, 0) == -1) {
+ saved_errno = errno;
+ close(fd);
+ errno = saved_errno;
+ return -1;
+ }
+ close(fd);
+ }
+
+ return 0;
+}
+
+void
+sandbox_main_process(void)
+{
+ return;
+}
+
+void
+sandbox_server_process(void)
+{
+ if (landlock_unveil("/", "r") == -1)
+ fatal("landlock_unveil(/)");
+
+ if (landlock_unveil(NULL, NULL) == -1)
+ fatal("landlock_unveil(NULL, NULL)");
+}
+
+void
+sandbox_crypto_process(void)
+{
+ /* contrary to unveil(2), this removes all fs access. */
+ if (landlock_unveil(NULL, NULL) == -1)
+ fatal("landlock_unveil(NULL, NULL)");
+}
+
+void
+sandbox_logger_process(void)
+{
+ /* contrary to unveil(2), this removes all fs access. */
+ if (landlock_unveil(NULL, NULL) == -1)
+ fatal("landlock_unveil(NULL, NULL)");
+}
+
#else
void
