/*
* Copyright (C) 2015 John Crispin <blogic@openwrt.org>
* Copyright (C) 2015 Etienne Champetier <champetier.etienne@gmail.com>
+ * Copyright (C) 2020 Daniel Golle <daniel@makrotopia.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1
#include <fcntl.h>
#include <linux/limits.h>
#include <stdlib.h>
+#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <unistd.h>
+#include <libgen.h>
#include <libubox/avl.h>
#include <libubox/avl-cmp.h>
+#include <libubox/blobmsg.h>
+#include <libubox/list.h>
+#include <libubox/utils.h>
#include "elf.h"
#include "fs.h"
#include "jail.h"
#include "log.h"
+#define UJAIL_NOAFILE "/tmp/.ujailnoafile"
+
struct mount {
- struct avl_node avl;
- const char *path;
- int readonly;
- int error;
+ struct avl_node avl;
+ const char *source;
+ const char *target;
+ const char *filesystemtype;
+ unsigned long mountflags;
+ unsigned long propflags;
+ const char *optstr;
+ int error;
+ bool inner;
};
struct avl_tree mounts;
-int add_mount(const char *path, int readonly, int error)
+static int do_mount(const char *root, const char *orig_source, const char *target, const char *filesystemtype,
+ unsigned long orig_mountflags, unsigned long propflags, const char *optstr, int error, bool inner)
{
- assert(path != NULL);
+ struct stat s;
+ char new[PATH_MAX];
+ char *source = (char *)orig_source;
+ int fd;
+ bool is_bind = (orig_mountflags & MS_BIND);
+ bool is_mask = (source == (void *)(-1));
+ unsigned long mountflags = orig_mountflags;
+
+ if (source && is_bind && stat(source, &s)) {
+ ERROR("stat(%s) failed: %m\n", source);
+ return error;
+ }
+
+ if (!is_mask && orig_source && inner) {
+ if (asprintf(&source, "%s%s", root, orig_source) < 0)
+ return ENOMEM;
+ }
+
+ snprintf(new, sizeof(new), "%s%s", root, target?target:source);
+
+ if (is_mask) {
+ if (stat(new, &s))
+ return 0; /* doesn't exists, nothing to mask */
+
+ if (S_ISDIR(s.st_mode)) {/* use empty 0-sized tmpfs for directories */
+ if (mount(NULL, new, "tmpfs", MS_RDONLY | MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_NOATIME, "size=0,mode=000"))
+ return error;
+ } else {
+ /* mount-bind 0-sized file having mode 000 */
+ if (mount(UJAIL_NOAFILE, new, "bind", MS_BIND, NULL))
+ return error;
+
+ if (mount(UJAIL_NOAFILE, new, "bind", MS_REMOUNT | MS_BIND | MS_RDONLY | MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_NOATIME, NULL))
+ return error;
+ }
+
+ DEBUG("masked path %s\n", new);
+ return 0;
+ }
+
+
+ if (!is_bind || (source && S_ISDIR(s.st_mode))) {
+ mkdir_p(new, 0755);
+ } else if (is_bind && source) {
+ mkdir_p(dirname(new), 0755);
+ snprintf(new, sizeof(new), "%s%s", root, target?target:source);
+ fd = creat(new, 0644);
+ if (fd == -1) {
+ ERROR("creat(%s) failed: %m\n", new);
+ return error;
+ }
+ close(fd);
+ }
+
+ if (is_bind) {
+ if (mount(source?:new, new, filesystemtype?:"bind", MS_BIND | (mountflags & MS_REC), optstr)) {
+ if (error)
+ ERROR("failed to mount -B %s %s: %m\n", source, new);
+
+ if (inner)
+ free(source);
+
+ return error;
+ }
+ mountflags |= MS_REMOUNT;
+ }
+
+ const char *hack_fstype = ((!filesystemtype || strcmp(filesystemtype, "cgroup"))?filesystemtype:"cgroup2");
+ if (mount(source?:(is_bind?new:NULL), new, hack_fstype?:"none", mountflags, optstr)) {
+ if (error)
+ ERROR("failed to mount %s %s: %m\n", source, new);
+
+ if (inner)
+ free(source);
+
+ return error;
+ }
+
+ DEBUG("mount %s%s %s (%s)\n", (mountflags & MS_BIND)?"-B ":"", source, new,
+ (mountflags & MS_RDONLY)?"ro":"rw");
+
+ if (propflags && mount("none", new, "none", propflags, NULL)) {
+ if (error)
+ ERROR("failed to mount --make-... %s \n", new);
+
+ if (inner)
+ free(source);
+
+ return error;
+ }
+
+ if (inner)
+ free(source);
- if (avl_find(&mounts, path))
+ return 0;
+}
+
+static int _add_mount(const char *source, const char *target, const char *filesystemtype,
+ unsigned long mountflags, unsigned long propflags, const char *optstr,
+ int error, bool inner)
+{
+ assert(target != NULL);
+
+ if (avl_find(&mounts, target))
return 1;
struct mount *m;
m = calloc(1, sizeof(struct mount));
assert(m != NULL);
- m->avl.key = m->path = strdup(path);
- m->readonly = readonly;
+ m->avl.key = m->target = strdup(target);
+ if (source) {
+ if (source != (void*)(-1))
+ m->source = strdup(source);
+ else
+ m->source = (void*)(-1);
+ }
+ if (filesystemtype)
+ m->filesystemtype = strdup(filesystemtype);
+
+ if (optstr)
+ m->optstr = strdup(optstr);
+
+ m->mountflags = mountflags;
+ m->propflags = propflags;
m->error = error;
+ m->inner = inner;
avl_insert(&mounts, &m->avl);
- DEBUG("adding mount %s ro(%d) err(%d)\n", m->path, m->readonly, m->error != 0);
+ DEBUG("adding mount %s %s bind(%d) ro(%d) err(%d)\n", (m->source == (void*)(-1))?"mask":m->source, m->target,
+ !!(m->mountflags & MS_BIND), !!(m->mountflags & MS_RDONLY), m->error != 0);
+
+ return 0;
+}
+
+int add_mount(const char *source, const char *target, const char *filesystemtype,
+ unsigned long mountflags, unsigned long propflags, const char *optstr, int error)
+{
+ return _add_mount(source, target, filesystemtype, mountflags, propflags, optstr, error, false);
+}
+
+int add_mount_inner(const char *source, const char *target, const char *filesystemtype,
+ unsigned long mountflags, unsigned long propflags, const char *optstr, int error)
+{
+ return _add_mount(source, target, filesystemtype, mountflags, propflags, optstr, error, true);
+}
+
+int add_mount_bind(const char *path, int readonly, int error)
+{
+ unsigned long mountflags = MS_BIND;
+
+ if (readonly)
+ mountflags |= MS_RDONLY;
+
+ return add_mount(path, path, NULL, mountflags, 0, NULL, error);
+}
+
+enum {
+ OCI_MOUNT_SOURCE,
+ OCI_MOUNT_DESTINATION,
+ OCI_MOUNT_TYPE,
+ OCI_MOUNT_OPTIONS,
+ __OCI_MOUNT_MAX,
+};
+
+static const struct blobmsg_policy oci_mount_policy[] = {
+ [OCI_MOUNT_SOURCE] = { "source", BLOBMSG_TYPE_STRING },
+ [OCI_MOUNT_DESTINATION] = { "destination", BLOBMSG_TYPE_STRING },
+ [OCI_MOUNT_TYPE] = { "type", BLOBMSG_TYPE_STRING },
+ [OCI_MOUNT_OPTIONS] = { "options", BLOBMSG_TYPE_ARRAY },
+};
+
+struct mount_opt {
+ struct list_head list;
+ char *optstr;
+};
+
+#ifndef MS_LAZYTIME
+#define MS_LAZYTIME (1 << 25)
+#endif
+
+static int parseOCImountopts(struct blob_attr *msg, unsigned long *mount_flags, unsigned long *propagation_flags, char **mount_data, int *error)
+{
+ struct blob_attr *cur;
+ int rem;
+ unsigned long mf = 0;
+ unsigned long pf = 0;
+ char *tmp;
+ struct list_head fsopts = LIST_HEAD_INIT(fsopts);
+ size_t len = 0;
+ struct mount_opt *opt, *tmpopt;
+
+ blobmsg_for_each_attr(cur, msg, rem) {
+ tmp = blobmsg_get_string(cur);
+ if (!strcmp("ro", tmp))
+ mf |= MS_RDONLY;
+ else if (!strcmp("rw", tmp))
+ mf &= ~MS_RDONLY;
+ else if (!strcmp("bind", tmp))
+ mf = MS_BIND;
+ else if (!strcmp("rbind", tmp))
+ mf |= MS_BIND | MS_REC;
+ else if (!strcmp("sync", tmp))
+ mf |= MS_SYNCHRONOUS;
+ else if (!strcmp("async", tmp))
+ mf &= ~MS_SYNCHRONOUS;
+ else if (!strcmp("atime", tmp))
+ mf &= ~MS_NOATIME;
+ else if (!strcmp("noatime", tmp))
+ mf |= MS_NOATIME;
+ else if (!strcmp("defaults", tmp))
+ mf = 0; /* rw, suid, dev, exec, auto, nouser, and async */
+ else if (!strcmp("dev", tmp))
+ mf &= ~MS_NODEV;
+ else if (!strcmp("nodev", tmp))
+ mf |= MS_NODEV;
+ else if (!strcmp("iversion", tmp))
+ mf |= MS_I_VERSION;
+ else if (!strcmp("noiversion", tmp))
+ mf &= ~MS_I_VERSION;
+ else if (!strcmp("diratime", tmp))
+ mf &= ~MS_NODIRATIME;
+ else if (!strcmp("nodiratime", tmp))
+ mf |= MS_NODIRATIME;
+ else if (!strcmp("dirsync", tmp))
+ mf |= MS_DIRSYNC;
+ else if (!strcmp("exec", tmp))
+ mf &= ~MS_NOEXEC;
+ else if (!strcmp("noexec", tmp))
+ mf |= MS_NOEXEC;
+ else if (!strcmp("mand", tmp))
+ mf |= MS_MANDLOCK;
+ else if (!strcmp("nomand", tmp))
+ mf &= ~MS_MANDLOCK;
+ else if (!strcmp("relatime", tmp))
+ mf |= MS_RELATIME;
+ else if (!strcmp("norelatime", tmp))
+ mf &= ~MS_RELATIME;
+ else if (!strcmp("strictatime", tmp))
+ mf |= MS_STRICTATIME;
+ else if (!strcmp("nostrictatime", tmp))
+ mf &= ~MS_STRICTATIME;
+ else if (!strcmp("lazytime", tmp))
+ mf |= MS_LAZYTIME;
+ else if (!strcmp("nolazytime", tmp))
+ mf &= ~MS_LAZYTIME;
+ else if (!strcmp("suid", tmp))
+ mf &= ~MS_NOSUID;
+ else if (!strcmp("nosuid", tmp))
+ mf |= MS_NOSUID;
+ else if (!strcmp("remount", tmp))
+ mf |= MS_REMOUNT;
+ /* propagation flags */
+ else if (!strcmp("private", tmp))
+ pf |= MS_PRIVATE;
+ else if (!strcmp("rprivate", tmp))
+ pf |= MS_PRIVATE | MS_REC;
+ else if (!strcmp("slave", tmp))
+ pf |= MS_SLAVE;
+ else if (!strcmp("rslave", tmp))
+ pf |= MS_SLAVE | MS_REC;
+ else if (!strcmp("shared", tmp))
+ pf |= MS_SHARED;
+ else if (!strcmp("rshared", tmp))
+ pf |= MS_SHARED | MS_REC;
+ else if (!strcmp("unbindable", tmp))
+ pf |= MS_UNBINDABLE;
+ else if (!strcmp("runbindable", tmp))
+ pf |= MS_UNBINDABLE | MS_REC;
+ /* special case: 'nofail' */
+ else if(!strcmp("nofail", tmp))
+ *error = 0;
+ else if (!strcmp("auto", tmp) ||
+ !strcmp("noauto", tmp) ||
+ !strcmp("user", tmp) ||
+ !strcmp("group", tmp) ||
+ !strcmp("_netdev", tmp))
+ DEBUG("ignoring built-in mount option %s\n", tmp);
+ else {
+ /* filesystem-specific free-form option */
+ opt = calloc(1, sizeof(*opt));
+ opt->optstr = tmp;
+ list_add_tail(&opt->list, &fsopts);
+ }
+ };
+
+ *mount_flags = mf;
+ *propagation_flags = pf;
+
+ list_for_each_entry(opt, &fsopts, list) {
+ if (len)
+ ++len;
+
+ len += strlen(opt->optstr);
+ };
+
+ if (len) {
+ *mount_data = calloc(len + 1, sizeof(char));
+ if (!mount_data)
+ return ENOMEM;
+
+ len = 0;
+ list_for_each_entry(opt, &fsopts, list) {
+ if (len)
+ strcat(*mount_data, ",");
+
+ strcat(*mount_data, opt->optstr);
+ ++len;
+ }
+
+ list_for_each_entry_safe(opt, tmpopt, &fsopts, list) {
+ list_del(&opt->list);
+ free(opt);
+ }
+ }
+
+ DEBUG("mount flags(%08lx) propagation(%08lx) fsopts(\"%s\")\n", mf, pf, *mount_data?:"");
+
return 0;
}
+int parseOCImount(struct blob_attr *msg)
+{
+ struct blob_attr *tb[__OCI_MOUNT_MAX];
+ unsigned long mount_flags = 0;
+ unsigned long propagation_flags = 0;
+ char *mount_data = NULL;
+ int ret, err = -1;
+
+ blobmsg_parse(oci_mount_policy, __OCI_MOUNT_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
+
+ if (!tb[OCI_MOUNT_DESTINATION])
+ return EINVAL;
+
+ if (tb[OCI_MOUNT_OPTIONS]) {
+ ret = parseOCImountopts(tb[OCI_MOUNT_OPTIONS], &mount_flags, &propagation_flags, &mount_data, &err);
+ if (ret)
+ return ret;
+ }
+
+ ret = add_mount(tb[OCI_MOUNT_SOURCE] ? blobmsg_get_string(tb[OCI_MOUNT_SOURCE]) : NULL,
+ blobmsg_get_string(tb[OCI_MOUNT_DESTINATION]),
+ tb[OCI_MOUNT_TYPE] ? blobmsg_get_string(tb[OCI_MOUNT_TYPE]) : NULL,
+ mount_flags, propagation_flags, mount_data, err);
+
+ if (mount_data)
+ free(mount_data);
+
+ return ret;
+}
+
+static void build_noafile(void) {
+ int fd;
+
+ fd = creat(UJAIL_NOAFILE, 0000);
+ if (fd == -1)
+ return;
+
+ close(fd);
+ return;
+}
+
int mount_all(const char *jailroot) {
struct library *l;
struct mount *m;
+ build_noafile();
+
avl_for_each_element(&libraries, l, avl)
- add_mount(l->path, 1, -1);
+ add_mount_bind(l->path, 1, -1);
avl_for_each_element(&mounts, m, avl)
- if (mount_bind(jailroot, m->path, m->readonly, m->error))
+ if (do_mount(jailroot, m->source, m->target, m->filesystemtype, m->mountflags,
+ m->propflags, m->optstr, m->error, m->inner))
return -1;
return 0;
}
+void mount_free(void) {
+ struct mount *m, *tmp;
+
+ avl_remove_all_elements(&mounts, m, avl, tmp) {
+ if (m->source != (void*)(-1))
+ free((void*)m->source);
+ free((void*)m->target);
+ free((void*)m->filesystemtype);
+ free((void*)m->optstr);
+ free(m);
+ }
+}
+
void mount_list_init(void) {
avl_init(&mounts, avl_strcmp, false, NULL);
}
fd = open(path, O_RDONLY|O_CLOEXEC);
if (fd == -1)
return error;
- add_mount(path, readonly, error);
+ add_mount_bind(path, readonly, error);
} else {
if (avl_find(&libraries, path))
return 0;
struct stat s;
if (fstat(fd, &s) == -1) {
- ERROR("fstat(%s) failed: %s\n", path, strerror(errno));
+ ERROR("fstat(%s) failed: %m\n", path);
ret = error;
goto out;
}
map = mmap(NULL, s.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (map == MAP_FAILED) {
- ERROR("failed to mmap %s\n", path);
+ ERROR("failed to mmap %s: %m\n", path);
ret = -1;
goto out;
}
projects / project / procd.git / blobdiff