src/shared/memfd.c

	memfd.c revision 4632777024b7ba210e4efe5cfabc8cd0b5991045
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering/***
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  This file is part of systemd.
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  Copyright 2013 Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  systemd is free software; you can redistribute it and/or modify it
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  under the terms of the GNU Lesser General Public License as published by
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  the Free Software Foundation; either version 2.1 of the License, or
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  (at your option) any later version.
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  systemd is distributed in the hope that it will be useful, but
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  WITHOUT ANY WARRANTY; without even the implied warranty of
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  Lesser General Public License for more details.
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  You should have received a copy of the GNU Lesser General Public License
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering  along with systemd; If not, see <http://www.gnu.org/licenses/>.
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering***/
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include <stdio.h>
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include <fcntl.h>
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include <sys/ioctl.h>
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include <sys/mman.h>
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include <sys/prctl.h>
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include "util.h"
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include "bus-label.h"
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include "missing.h"
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include "memfd.h"
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering#include "sd-bus.h"
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringstruct sd_memfd {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int fd;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        FILE *f;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering};
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_new(sd_memfd **m, const char *name) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        _cleanup_close_ int kdbus = -1;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        _cleanup_free_ char *g = NULL;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        sd_memfd *n;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        kdbus = open("/dev/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (kdbus < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (name) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                /* The kernel side is pretty picky about the character
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                 * set here, let's do the usual bus escaping to deal
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                 * with that. */
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                g = bus_label_escape(name);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                if (!g)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        return -ENOMEM;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                name = g;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        } else {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                char pr[17] = {};
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                /* If no name is specified we generate one. We include
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                 * a hint indicating our library implementation, and
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                 * add the thread name to it */
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                assert_se(prctl(PR_GET_NAME, (unsigned long) pr) >= 0);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                if (isempty(pr))
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        name = "sd";
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                else {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        _cleanup_free_ char *e = NULL;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        e = bus_label_escape(pr);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        if (!e)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                                return -ENOMEM;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        g = strappend("sd-", e);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        if (!g)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                                return -ENOMEM;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        name = g;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                }
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        }
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        n = new0(struct sd_memfd, 1);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!n)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -ENOMEM;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        n->fd = memfd_create(name, MFD_ALLOW_SEALING);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (n->fd < 0) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                free(n);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        }
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        *m = n;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_new_from_fd(sd_memfd **m, int fd) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        sd_memfd *n;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(fd >= 0, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        /* Check if this is a sealable fd */
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (fcntl(fd, F_GET_SEALS) < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -ENOTTY;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        n = new0(struct sd_memfd, 1);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!n)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -ENOMEM;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        n->fd = fd;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        *m = n;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringvoid sd_memfd_free(sd_memfd *m) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!m)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (m->f)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                fclose(m->f);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        else
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                safe_close(m->fd);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        free(m);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_get_fd(sd_memfd *m) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return m->fd;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_get_file(sd_memfd *m, FILE **f) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(f, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!m->f) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                m->f = fdopen(m->fd, "r+");
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                if (!m->f)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                        return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        }
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        *f = m->f;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_dup_fd(sd_memfd *m) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int fd;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        fd = fcntl(m->fd, F_DUPFD_CLOEXEC, 3);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (fd < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return fd;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_map(sd_memfd *m, uint64_t offset, size_t size, void **p) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        void *q;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int sealed;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(size > 0, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(p, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        sealed = sd_memfd_get_sealed(m);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (sealed < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return sealed;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        q = mmap(NULL, size, sealed ? PROT_READ : PROT_READ|PROT_WRITE, MAP_PRIVATE, m->fd, offset);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (q == MAP_FAILED)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        *p = q;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_set_sealed(sd_memfd *m) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        r = fcntl(m->fd, F_ADD_SEALS, F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (r < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_get_sealed(sd_memfd *m) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        r = fcntl(m->fd, F_GET_SEALS);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (r < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return (r & (F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE)) ==
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                    (F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_get_size(sd_memfd *m, uint64_t *sz) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        struct stat stat;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(sz, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        r = fstat(m->fd, &stat);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (r < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        *sz = stat.st_size;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_set_size(sd_memfd *m, uint64_t sz) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        r = ftruncate(m->fd, sz);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (r < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_new_and_map(sd_memfd **m, const char *name, size_t sz, void **p) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        sd_memfd *n;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        int r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        r = sd_memfd_new(&n, name);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (r < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        r = sd_memfd_set_size(n, sz);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (r < 0) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                sd_memfd_free(n);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        }
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        r = sd_memfd_map(n, 0, sz, p);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (r < 0) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                sd_memfd_free(n);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return r;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        }
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        *m = n;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poetteringint sd_memfd_get_name(sd_memfd *m, char **name) {
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        char path[sizeof("/proc/self/fd/") + DECIMAL_STR_MAX(int)], buf[FILENAME_MAX+1], *e;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        const char *delim, *end;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        _cleanup_free_ char *n = NULL;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        ssize_t k;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(m, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        assert_return(name, -EINVAL);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        sprintf(path, "/proc/self/fd/%i", m->fd);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        k = readlink(path, buf, sizeof(buf));
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (k < 0)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -errno;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if ((size_t) k >= sizeof(buf))
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -E2BIG;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        buf[k] = 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        delim = strstr(buf, ":[");
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!delim)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -EIO;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        delim = strchr(delim + 2, ':');
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!delim)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -EIO;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        delim++;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        end = strchr(delim, ']');
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!end)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -EIO;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        n = strndup(delim, end - delim);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!n)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -ENOMEM;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        e = bus_label_unescape(n);
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        if (!e)
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering                return -ENOMEM;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        *name = e;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering        return 0;
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering}
839a4a20d8b4f6ebf3a342fd05c821358be5a313Lennart Poettering