From: ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org (Eric W. Biederman)
To: "Nicolas François"
<nicolas.francois-Fa7rcPG4DJn7nK0/Xc0eeg@public.gmane.org>
Cc: Linux Containers
<containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>,
Pkg-shadow-devel-XbBxUvOt3X2LieD7tvxI8l/i77bcL1HB@public.gmane.org,
"Michael Kerrisk (man-pages)"
<mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: [PATCH 11/11] newuidmap, newgidmap: New suid helpers for using subordinate uids and gids
Date: Tue, 22 Jan 2013 01:20:07 -0800 [thread overview]
Message-ID: <87ehhdpoag.fsf@xmission.com> (raw)
In-Reply-To: <87d2wxshu0.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org> (Eric W. Biederman's message of "Tue, 22 Jan 2013 01:11:19 -0800")
Signed-off-by: "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
---
libmisc/Makefile.am | 2 +
libmisc/idmapping.c | 126 +++++++++++++++++++++++++++++++++++
libmisc/idmapping.h | 44 ++++++++++++
man/Makefile.am | 4 +
man/newgidmap.1.xml | 157 +++++++++++++++++++++++++++++++++++++++++++
man/newuidmap.1.xml | 154 +++++++++++++++++++++++++++++++++++++++++++
src/Makefile.am | 5 +-
src/newgidmap.c | 183 +++++++++++++++++++++++++++++++++++++++++++++++++++
src/newuidmap.c | 183 +++++++++++++++++++++++++++++++++++++++++++++++++++
9 files changed, 856 insertions(+), 2 deletions(-)
create mode 100644 libmisc/idmapping.c
create mode 100644 libmisc/idmapping.h
create mode 100644 man/newgidmap.1.xml
create mode 100644 man/newuidmap.1.xml
create mode 100644 src/newgidmap.c
create mode 100644 src/newuidmap.c
diff --git a/libmisc/Makefile.am b/libmisc/Makefile.am
index 5de9193..76f3c05 100644
--- a/libmisc/Makefile.am
+++ b/libmisc/Makefile.am
@@ -32,6 +32,8 @@ libmisc_a_SOURCES = \
getgr_nam_gid.c \
getrange.c \
hushed.c \
+ idmapping.h \
+ idmapping.c \
isexpired.c \
limits.c \
list.c log.c \
diff --git a/libmisc/idmapping.c b/libmisc/idmapping.c
new file mode 100644
index 0000000..cb9e898
--- /dev/null
+++ b/libmisc/idmapping.c
@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2013 Eric Biederman
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the copyright holders or contributors may not be used to
+ * endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <config.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdlib.h>
+#include "prototypes.h"
+#include "idmapping.h"
+
+struct map_range *get_map_ranges(int ranges, int argc, char **argv)
+{
+ struct map_range *mappings, *mapping;
+ int idx, argidx;
+
+ if ((ranges * 3) > argc) {
+ fprintf(stderr, "ranges: %u argc: %d\n",
+ ranges, argc);
+ fprintf(stderr,
+ _( "%s: Not enough arguments to form %u mappings\n"),
+ Prog, ranges);
+ return NULL;
+ }
+
+ mappings = calloc(ranges, sizeof(*mappings));
+ if (!mappings) {
+ fprintf(stderr, _( "%s: Memory allocation failure\n"),
+ Prog);
+ exit(EXIT_FAILURE);
+ }
+
+ /* Gather up the ranges from the command line */
+ mapping = mappings;
+ for (idx = 0; idx < ranges; idx++, argidx += 3, mapping++) {
+ if (!getulong(argv[argidx + 0], &mapping->upper))
+ return NULL;
+ if (!getulong(argv[argidx + 1], &mapping->lower))
+ return NULL;
+ if (!getulong(argv[argidx + 2], &mapping->count))
+ return NULL;
+ }
+ return mappings;
+}
+
+/* Number of ascii digits needed to print any unsigned long in decimal.
+ * There are approximately 10 bits for every 3 decimal digits.
+ * So from bits to digits the formula is roundup((Number of bits)/10) * 3.
+ * For common sizes of integers this works out to:
+ * 2bytes --> 6 ascii estimate -> 65536 (5 real)
+ * 4bytes --> 12 ascii estimated -> 4294967296 (10 real)
+ * 8bytes --> 21 ascii estimated -> 18446744073709551616 (20 real)
+ * 16bytes --> 39 ascii estimated -> 340282366920938463463374607431768211456 (39 real)
+ */
+#define ULONG_DIGITS ((((sizeof(unsigned long) * CHAR_BIT) + 9)/10)*3)
+
+
+void write_mapping(int proc_dir_fd, int ranges, struct map_range *mappings,
+ const char *map_file)
+{
+ int idx;
+ struct map_range *mapping;
+ size_t bufsize;
+ char *buf, *pos;
+ int fd;
+
+ bufsize = ranges * ((ULONG_DIGITS + 1) * 3);
+ pos = buf = xmalloc(bufsize);
+
+ /* Build the mapping command */
+ mapping = mappings;
+ for (idx = 0; idx < ranges; idx++, mapping++) {
+ /* Append this range to the string that will be written */
+ int written = snprintf(pos, bufsize - (pos - buf),
+ "%lu %lu %lu\n",
+ mapping->upper,
+ mapping->lower,
+ mapping->count);
+ if ((written <= 0) || (written >= (bufsize - (pos - buf)))) {
+ fprintf(stderr, _("%s: snprintf failed!\n"), Prog);
+ exit(EXIT_FAILURE);
+ }
+ pos += written;
+ }
+
+ /* Write the mapping to the maping file */
+ fd = openat(proc_dir_fd, map_file, O_WRONLY);
+ if (fd < 0) {
+ fprintf(stderr, _("%s: open of %s failed: %s\n"),
+ Prog, map_file, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ if (write(fd, buf, pos - buf) != (pos - buf)) {
+ fprintf(stderr, _("%s: write to %s failed: %s\n"),
+ Prog, map_file, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ close(fd);
+}
diff --git a/libmisc/idmapping.h b/libmisc/idmapping.h
new file mode 100644
index 0000000..88cf761
--- /dev/null
+++ b/libmisc/idmapping.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2013 Eric Biederman
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the copyright holders or contributors may not be used to
+ * endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _IDMAPPING_H_
+#define _IDMAPPING_H_
+
+struct map_range {
+ unsigned long upper;
+ unsigned long lower;
+ unsigned long count;
+};
+
+extern struct map_range *get_map_ranges(int ranges, int argc, char **argv);
+extern void write_mapping(int proc_dir_fd, int ranges,
+ struct map_range *mappings, const char *map_file);
+
+#endif /* _ID_MAPPING_H_ */
+
diff --git a/man/Makefile.am b/man/Makefile.am
index fc617e9..b50ca41 100644
--- a/man/Makefile.am
+++ b/man/Makefile.am
@@ -30,7 +30,9 @@ man_MANS = \
man1/login.1 \
man5/login.defs.5 \
man8/logoutd.8 \
+ man1/newgidmap.1 \
man1/newgrp.1 \
+ man1/newuidmap.1 \
man8/newusers.8 \
man8/nologin.8 \
man1/passwd.1 \
@@ -83,7 +85,9 @@ man_XMANS = \
login.access.5.xml \
login.defs.5.xml \
logoutd.8.xml \
+ newgidmap.1.xml \
newgrp.1.xml \
+ newuidmap.1.xml \
newusers.8.xml \
nologin.8.xml \
passwd.1.xml \
diff --git a/man/newgidmap.1.xml b/man/newgidmap.1.xml
new file mode 100644
index 0000000..424a480
--- /dev/null
+++ b/man/newgidmap.1.xml
@@ -0,0 +1,157 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ Copyright (c) 2013 Eric W. Biederman
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+ 3. The name of the copyright holders or contributors may not be used to
+ endorse or promote products derived from this software without
+ specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
+ "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
+<!-- SHADOW-CONFIG-HERE -->
+]>
+
+<refentry id='newgidmap.1'>
+ <refmeta>
+ <refentrytitle>newgidmap</refentrytitle>
+ <manvolnum>1</manvolnum>
+ <refmiscinfo class="sectdesc">User Commands</refmiscinfo>
+ <refmiscinfo class="source">shadow-utils</refmiscinfo>
+ <refmiscinfo class="version">&SHADOW_UTILS_VERSION;</refmiscinfo>
+ </refmeta>
+ <refnamediv id='name'>
+ <refname>newgidmap</refname>
+ <refpurpose>set the gid mapping of a user namespace</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv id='synopsis'>
+ <cmdsynopsis>
+ <command>newgidmap</command>
+ <arg choice='plain'>
+ <replaceable>pid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>gid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>lowergid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>count</replaceable>
+ </arg>
+ <arg choice='opt'>
+ <arg choice='plain'>
+ <replaceable>pid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>gid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>lowergid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>count</replaceable>
+ </arg>
+ <arg choice='opt'>
+ <replaceable>...</replaceable>
+ </arg>
+ </arg>
+ </cmdsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1 id='description'>
+ <title>DESCRIPTION</title>
+ <para>
+ The <command>newgidmap</command> sets <filename>/proc/[pid]/gid_map</filename> based on it's
+ command line arguments and the gids allowed in <filename>/etc/subgid</filename>.
+ </para>
+
+ </refsect1>
+
+ <refsect1 id='options'>
+ <title>OPTIONS</title>
+ <para>
+ There currently are no options to the <command>newgidmap</command> command.
+ </para>
+ <variablelist remap='IP'>
+ </variablelist>
+ </refsect1>
+
+ <refsect1 id='note'>
+ <title>NOTE</title>
+ <para>
+ The only restriction placed on the login shell is that the command
+ name must be listed in <filename>/etc/shells</filename>, unless the
+ invoker is the superuser, and then any value may be added. An
+ account with a restricted login shell may not change her login shell.
+ For this reason, placing <filename>/bin/rsh</filename> in
+ <filename>/etc/shells</filename> is discouraged since accidentally
+ changing to a restricted shell would prevent the user from ever
+ changing her login shell back to its original value.
+ </para>
+ </refsect1>
+
+
+ <refsect1 id='files'>
+ <title>FILES</title>
+ <variablelist>
+ <varlistentry>
+ <term><filename>/etc/subgid</filename></term>
+ <listitem>
+ <para>List of users subordinate user IDs.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/[pid]/gid_map</filename></term>
+ <listitem>
+ <para>Mapping of gids from one between user namespaces.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1 id='see_also'>
+ <title>SEE ALSO</title>
+ <para>
+ <citerefentry>
+ <refentrytitle>login.defs</refentrytitle><manvolnum>5</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>useradd</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>usermod</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>newusers</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>userdel</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>subgid</refentrytitle><manvolnum>5</manvolnum>
+ </citerefentry>.
+ </para>
+ </refsect1>
+</refentry>
diff --git a/man/newuidmap.1.xml b/man/newuidmap.1.xml
new file mode 100644
index 0000000..c6687ea
--- /dev/null
+++ b/man/newuidmap.1.xml
@@ -0,0 +1,154 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ Copyright (c) 2013 Eric W. Biederman
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+ 3. The name of the copyright holders or contributors may not be used to
+ endorse or promote products derived from this software without
+ specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
+ "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
+<!-- SHADOW-CONFIG-HERE -->
+]>
+
+<refentry id='newuidmap.1'>
+ <refmeta>
+ <refentrytitle>newuidmap</refentrytitle>
+ <manvolnum>1</manvolnum>
+ <refmiscinfo class="sectdesc">User Commands</refmiscinfo>
+ <refmiscinfo class="source">shadow-utils</refmiscinfo>
+ <refmiscinfo class="version">&SHADOW_UTILS_VERSION;</refmiscinfo>
+ </refmeta>
+ <refnamediv id='name'>
+ <refname>newuidmap</refname>
+ <refpurpose>set the uid mapping of a user namespace</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv id='synopsis'>
+ <cmdsynopsis>
+ <command>newuidmap</command>
+ <arg choice='plain'>
+ <replaceable>pid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>uid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>loweruid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>count</replaceable>
+ </arg>
+ <arg choice='opt'>
+ <arg choice='plain'>
+ <replaceable>uid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>loweruid</replaceable>
+ </arg>
+ <arg choice='plain'>
+ <replaceable>count</replaceable>
+ </arg>
+ <arg choice='opt'>
+ <replaceable>...</replaceable>
+ </arg>
+ </arg>
+ </cmdsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1 id='description'>
+ <title>DESCRIPTION</title>
+ <para>
+ The <command>newuidmap</command> sets <filename>/proc/[pid]/uid_map</filename> based on it's
+ command line arguments and the uids allowed in <filename>/etc/subuid</filename>.
+ </para>
+
+ </refsect1>
+
+ <refsect1 id='options'>
+ <title>OPTIONS</title>
+ <para>
+ There currently are no options to the <command>newuidmap</command> command.
+ </para>
+ <variablelist remap='IP'>
+ </variablelist>
+ </refsect1>
+
+ <refsect1 id='note'>
+ <title>NOTE</title>
+ <para>
+ The only restriction placed on the login shell is that the command
+ name must be listed in <filename>/etc/shells</filename>, unless the
+ invoker is the superuser, and then any value may be added. An
+ account with a restricted login shell may not change her login shell.
+ For this reason, placing <filename>/bin/rsh</filename> in
+ <filename>/etc/shells</filename> is discouraged since accidentally
+ changing to a restricted shell would prevent the user from ever
+ changing her login shell back to its original value.
+ </para>
+ </refsect1>
+
+
+ <refsect1 id='files'>
+ <title>FILES</title>
+ <variablelist>
+ <varlistentry>
+ <term><filename>/etc/subuid</filename></term>
+ <listitem>
+ <para>List of users subordinate user IDs.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/[pid]/uid_map</filename></term>
+ <listitem>
+ <para>Mapping of uids from one between user namespaces.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1 id='see_also'>
+ <title>SEE ALSO</title>
+ <para>
+ <citerefentry>
+ <refentrytitle>login.defs</refentrytitle><manvolnum>5</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>useradd</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>usermod</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>newusers</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>userdel</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>subuid</refentrytitle><manvolnum>5</manvolnum>
+ </citerefentry>.
+ </para>
+ </refsect1>
+</refentry>
diff --git a/src/Makefile.am b/src/Makefile.am
index 88cae99..1390cae 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -24,7 +24,8 @@ INCLUDES = \
bin_PROGRAMS = groups login su
sbin_PROGRAMS = nologin
-ubin_PROGRAMS = faillog lastlog chage chfn chsh expiry gpasswd newgrp passwd
+ubin_PROGRAMS = faillog lastlog chage chfn chsh expiry gpasswd newgrp passwd \
+ newgidmap newuidmap
usbin_PROGRAMS = \
chgpasswd \
chpasswd \
@@ -49,7 +50,7 @@ usbin_PROGRAMS = \
noinst_PROGRAMS = id sulogin
suidbins = su
-suidubins = chage chfn chsh expiry gpasswd newgrp passwd
+suidubins = chage chfn chsh expiry gpasswd newgrp passwd newuidmap newgidmap
if ACCT_TOOLS_SETUID
suidubins += chage chgpasswd chpasswd groupadd groupdel groupmod newusers useradd userdel usermod
endif
diff --git a/src/newgidmap.c b/src/newgidmap.c
new file mode 100644
index 0000000..1527a61
--- /dev/null
+++ b/src/newgidmap.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2013 Eric Biederman
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the copyright holders or contributors may not be used to
+ * endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "defines.h"
+#include "prototypes.h"
+#include "subordinateio.h"
+#include "idmapping.h"
+
+/*
+ * Global variables
+ */
+const char *Prog;
+
+static bool verify_range(struct passwd *pw, struct map_range *range)
+{
+ /* An empty range is invalid */
+ if (range->count == 0)
+ return false;
+
+ /* Test /etc/subgid */
+ if (have_sub_gids(pw->pw_name, range->lower, range->count))
+ return true;
+
+ /* Allow a process to map it's own gid */
+ if ((range->count == 1) && (pw->pw_gid == range->lower))
+ return true;
+
+ return false;
+}
+
+static void verify_ranges(struct passwd *pw, int ranges,
+ struct map_range *mappings)
+{
+ struct map_range *mapping;
+ int idx;
+
+ mapping = mappings;
+ for (idx = 0; idx < ranges; idx++, mapping++) {
+ if (!verify_range(pw, mapping)) {
+ fprintf(stderr, _( "%s: gid range [%lu-%lu) -> [%lu-%lu) not allowed\n"),
+ Prog,
+ mapping->upper,
+ mapping->upper + mapping->count,
+ mapping->lower,
+ mapping->lower + mapping->count);
+ exit(EXIT_FAILURE);
+ }
+ }
+}
+
+static void usage(void)
+{
+ fprintf(stderr, _("usage: %s <pid> <gid> <lowergid> <count> [ <gid> <lowergid> <count> ] ... \n"), Prog);
+ exit(EXIT_FAILURE);
+}
+
+/*
+ * newgidmap - Set the gid_map for the specified process
+ */
+int main(int argc, char **argv)
+{
+ char proc_dir_name[PATH_MAX];
+ char *target_str;
+ pid_t target, parent;
+ int proc_dir_fd;
+ int ranges;
+ struct map_range *mappings;
+ struct stat st;
+ struct passwd *pw;
+ int written;
+
+ Prog = Basename (argv[0]);
+
+ /*
+ * The valid syntax are
+ * newgidmap target_pid
+ */
+ if (argc < 2)
+ usage();
+
+ /* Find the process that needs it's user namespace
+ * gid mapping set.
+ */
+ target_str = argv[1];
+ if (!get_pid(target_str, &target))
+ usage();
+
+ written = snprintf(proc_dir_name, sizeof(proc_dir_name), "/proc/%u/",
+ target);
+ if ((written <= 0) || (written >= sizeof(proc_dir_name))) {
+ fprintf(stderr, "%s: snprintf of proc path failed: %s\n",
+ Prog, strerror(errno));
+ }
+
+ proc_dir_fd = open(proc_dir_name, O_DIRECTORY);
+ if (proc_dir_fd < 0) {
+ fprintf(stderr, _("%s: Could not open proc directory for target %u\n"),
+ Prog, target);
+ return EXIT_FAILURE;
+ }
+
+ /* Who am i? */
+ pw = get_my_pwent ();
+ if (NULL == pw) {
+ fprintf (stderr,
+ _("%s: Cannot determine your user name.\n"),
+ Prog);
+ SYSLOG ((LOG_WARN, "Cannot determine the user name of the caller (UID %lu)",
+ (unsigned long) getuid ()));
+ return EXIT_FAILURE;
+ }
+
+ /* Get the effective uid and effective gid of the target process */
+ if (fstat(proc_dir_fd, &st) < 0) {
+ fprintf(stderr, _("%s: Could not stat directory for target %u\n"),
+ Prog, target);
+ return EXIT_FAILURE;
+ }
+
+ /* Verify real user and real group matches the password entry
+ * and the effective user and group of the program whose
+ * mappings we have been asked to set.
+ */
+ if ((getuid() != pw->pw_uid) ||
+ (getgid() != pw->pw_gid) ||
+ (pw->pw_uid != st.st_uid) ||
+ (pw->pw_gid != st.st_gid)) {
+ fprintf(stderr, _( "%s: Target %u is owned by a different user\n" ),
+ Prog, target);
+ return EXIT_FAILURE;
+ }
+
+ if (!sub_gid_open(O_RDONLY)) {
+ return EXIT_FAILURE;
+ }
+
+ ranges = ((argc - 2) + 2) / 3;
+ mappings = get_map_ranges(ranges, argc - 2, argv + 2);
+ if (!mappings)
+ usage();
+
+ verify_ranges(pw, ranges, mappings);
+
+ write_mapping(proc_dir_fd, ranges, mappings, "gid_map");
+ sub_gid_close();
+
+ return EXIT_SUCCESS;
+}
diff --git a/src/newuidmap.c b/src/newuidmap.c
new file mode 100644
index 0000000..69c5094
--- /dev/null
+++ b/src/newuidmap.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2013 Eric Biederman
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the copyright holders or contributors may not be used to
+ * endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "defines.h"
+#include "prototypes.h"
+#include "subordinateio.h"
+#include "idmapping.h"
+
+/*
+ * Global variables
+ */
+const char *Prog;
+
+static bool verify_range(struct passwd *pw, struct map_range *range)
+{
+ /* An empty range is invalid */
+ if (range->count == 0)
+ return false;
+
+ /* Test /etc/subuid */
+ if (have_sub_uids(pw->pw_name, range->lower, range->count))
+ return true;
+
+ /* Allow a process to map it's own uid */
+ if ((range->count == 1) && (pw->pw_uid == range->lower))
+ return true;
+
+ return false;
+}
+
+static void verify_ranges(struct passwd *pw, int ranges,
+ struct map_range *mappings)
+{
+ struct map_range *mapping;
+ int idx;
+
+ mapping = mappings;
+ for (idx = 0; idx < ranges; idx++, mapping++) {
+ if (!verify_range(pw, mapping)) {
+ fprintf(stderr, _( "%s: uid range [%lu-%lu) -> [%lu-%lu) not allowed\n"),
+ Prog,
+ mapping->upper,
+ mapping->upper + mapping->count,
+ mapping->lower,
+ mapping->lower + mapping->count);
+ exit(EXIT_FAILURE);
+ }
+ }
+}
+
+void usage(void)
+{
+ fprintf(stderr, _("usage: %s <pid> <uid> <loweruid> <count> [ <uid> <loweruid> <count> ] ... \n"), Prog);
+ exit(EXIT_FAILURE);
+}
+
+/*
+ * newuidmap - Set the uid_map for the specified process
+ */
+int main(int argc, char **argv)
+{
+ char proc_dir_name[PATH_MAX];
+ char *target_str;
+ pid_t target, parent;
+ int proc_dir_fd;
+ int ranges;
+ struct map_range *mappings;
+ struct stat st;
+ struct passwd *pw;
+ int written;
+
+ Prog = Basename (argv[0]);
+
+ /*
+ * The valid syntax are
+ * newuidmap target_pid
+ */
+ if (argc < 2)
+ usage();
+
+ /* Find the process that needs it's user namespace
+ * uid mapping set.
+ */
+ target_str = argv[1];
+ if (!get_pid(target_str, &target))
+ usage();
+
+ written = snprintf(proc_dir_name, sizeof(proc_dir_name), "/proc/%u/",
+ target);
+ if ((written <= 0) || (written >= sizeof(proc_dir_name))) {
+ fprintf(stderr, "%s: snprintf of proc path failed: %s\n",
+ Prog, strerror(errno));
+ }
+
+ proc_dir_fd = open(proc_dir_name, O_DIRECTORY);
+ if (proc_dir_fd < 0) {
+ fprintf(stderr, _("%s: Could not open proc directory for target %u\n"),
+ Prog, target);
+ return EXIT_FAILURE;
+ }
+
+ /* Who am i? */
+ pw = get_my_pwent ();
+ if (NULL == pw) {
+ fprintf (stderr,
+ _("%s: Cannot determine your user name.\n"),
+ Prog);
+ SYSLOG ((LOG_WARN, "Cannot determine the user name of the caller (UID %lu)",
+ (unsigned long) getuid ()));
+ return EXIT_FAILURE;
+ }
+
+ /* Get the effective uid and effective gid of the target process */
+ if (fstat(proc_dir_fd, &st) < 0) {
+ fprintf(stderr, _("%s: Could not stat directory for target %u\n"),
+ Prog, target);
+ return EXIT_FAILURE;
+ }
+
+ /* Verify real user and real group matches the password entry
+ * and the effective user and group of the program whose
+ * mappings we have been asked to set.
+ */
+ if ((getuid() != pw->pw_uid) ||
+ (getgid() != pw->pw_gid) ||
+ (pw->pw_uid != st.st_uid) ||
+ (pw->pw_gid != st.st_gid)) {
+ fprintf(stderr, _( "%s: Target %u is owned by a different user\n" ),
+ Prog, target);
+ return EXIT_FAILURE;
+ }
+
+ if (!sub_uid_open(O_RDONLY)) {
+ return EXIT_FAILURE;
+ }
+
+ ranges = ((argc - 2) + 2) / 3;
+ mappings = get_map_ranges(ranges, argc - 2, argv + 2);
+ if (!mappings)
+ usage();
+
+ verify_ranges(pw, ranges, mappings);
+
+ write_mapping(proc_dir_fd, ranges, mappings, "uid_map");
+ sub_uid_close();
+
+ return EXIT_SUCCESS;
+}
--
1.7.5.4
next prev parent reply other threads:[~2013-01-22 9:20 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-22 9:11 [PATCH 00/11] pkg-shadow support subordinate ids with user namespaces Eric W. Biederman
[not found] ` <87d2wxshu0.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-01-22 9:12 ` [PATCH 01/11] Documentation for /etc/subuid and /etc/subgid Eric W. Biederman
2013-01-22 9:12 ` [PATCH 02/11] login.defs.5: Document the new variables in login.defs Eric W. Biederman
2013-01-22 9:13 ` [PATCH 03/11] Implement commonio_append Eric W. Biederman
2013-01-22 9:13 ` Eric W. Biederman
2013-01-22 9:14 ` [PATCH 04/11] Add backend support for suboridnate uids and gids Eric W. Biederman
[not found] ` <87liblr344.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-01-23 18:22 ` Serge E. Hallyn
[not found] ` <20130123182206.GA4468-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-01-24 22:42 ` Eric W. Biederman
[not found] ` <87a9ryyzh2.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-01-24 22:50 ` Serge Hallyn
2013-01-24 22:59 ` Eric W. Biederman
2013-01-24 23:13 ` [PATCH] subordinateio: Fix subordinate_parse to have an internal static buffer Eric W. Biederman
2013-01-22 9:15 ` [PATCH 05/11] Implement find_new_sub_uids find_new_sub_gids Eric W. Biederman
2013-01-22 9:16 ` [PATCH 06/11] userdel: Add support for removing subordinate user and group ids Eric W. Biederman
2013-01-22 9:17 ` [PATCH 07/11] useradd: Add support for subordinate user identifiers Eric W. Biederman
2013-01-22 9:17 ` [PATCH 08/11] Add support for detecting busy subordinate user ids Eric W. Biederman
2013-01-22 9:18 ` [PATCH 09/11] usermod: Add support for subordinate uids and gids Eric W. Biederman
2013-01-22 9:19 ` [PATCH 10/11] newusers: Add support for assiging " Eric W. Biederman
2013-01-22 9:20 ` Eric W. Biederman [this message]
[not found] ` <87ehhdpoag.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-02-04 18:31 ` [PATCH 11/11] newuidmap,newgidmap: New suid helpers for using " Serge E. Hallyn
[not found] ` <20130204183129.GA27179-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-02-05 17:20 ` Serge E. Hallyn
2013-02-06 0:28 ` [PATCH 11/11] newuidmap, newgidmap: " Eric W. Biederman
[not found] ` <87sj5ai8us.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-02-06 3:00 ` [PATCH 11/11] newuidmap,newgidmap: " Serge E. Hallyn
[not found] ` <87fw1tr33a.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-06-15 0:15 ` [PATCH 05/11] Implement find_new_sub_uids find_new_sub_gids Seth Arnold
2013-10-25 20:30 ` [PATCH 11/11] newuidmap,newgidmap: New suid helpers for using subordinate uids and gids Serge E. Hallyn
[not found] ` <20131025203025.GA2467-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-10-26 0:42 ` [PATCH 11/11] newuidmap, newgidmap: " Eric W. Biederman
[not found] ` <87zjpw278b.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-10-26 2:33 ` Serge Hallyn
2013-10-26 21:50 ` Eric W. Biederman
[not found] ` <87iowjya4j.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-10-27 23:53 ` Serge E. Hallyn
2013-01-29 18:15 ` [PATCH 00/11] pkg-shadow support subordinate ids with user namespaces Rob Landley
2013-01-29 22:28 ` Eric W. Biederman
2013-01-30 5:35 ` Vasily Kulikov
2013-01-30 6:40 ` Eric W. Biederman
[not found] ` <87vcafyy0k.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-01-30 7:38 ` Vasily Kulikov
2013-02-22 12:16 ` Glauber Costa
[not found] ` <51276189.5040803-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org>
2013-02-22 16:34 ` Eric W. Biederman
[not found] ` <87zjyw489z.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-02-22 17:09 ` Glauber Costa
[not found] ` <5127A657.3010909-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org>
2013-02-25 14:34 ` Serge Hallyn
[not found] ` <20130225143451.GE4387@sergelap>
2013-02-25 14:38 ` Glauber Costa
[not found] ` <512B7773.9060704-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org>
2013-02-25 15:15 ` Serge Hallyn
2013-02-26 1:03 ` Eric W. Biederman
2013-02-25 14:30 ` Serge Hallyn
2013-03-03 15:37 ` Serge E. Hallyn
2013-03-07 15:23 ` Dwight Engen
2013-07-28 17:14 ` [Pkg-shadow-devel] " Christian PERRIER
[not found] ` <20130728171451.GX5670-FvNwPcshoeM/MCprI7ZU+I/wHUNs+SP4HZ5vskTnxNA@public.gmane.org>
2013-07-28 17:58 ` Eric W. Biederman
[not found] ` <87r4eilg6y.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-07-29 0:33 ` Serge Hallyn
[not found] ` <11218395-363e-46cd-b7a1-4488079a4986@email.android.com>
[not found] ` <11218395-363e-46cd-b7a1-4488079a4986-2ueSQiBKiTY7tOexoI0I+QC/G2K4zDHf@public.gmane.org>
2013-08-06 14:54 ` Serge E. Hallyn
[not found] ` <20130806145403.GA20913-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-08-06 22:53 ` Nicolas François
[not found] ` <20130806225332.GA14109-pDMkYksm/NDBVznEOA0nCqMXiC8k1aZu0e7PPNI6Mm0@public.gmane.org>
2013-08-07 15:33 ` Serge Hallyn
2013-08-07 18:04 ` Eric W. Biederman
[not found] ` <87eha5peb8.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-08-09 18:40 ` Nicolas François
[not found] ` <20130303153726.GA14737@austin.hallyn.com>
[not found] ` <20130303153726.GA14737-anj0Drq5vpzx6HRWoRZK3AC/G2K4zDHf@public.gmane.org>
2013-03-04 5:56 ` Christian PERRIER
[not found] ` <20130304055654.GE2629@mykerinos.kheops.frmug.org>
[not found] ` <20130304055654.GE2629-FvNwPcshoeM/MCprI7ZU+I/wHUNs+SP4HZ5vskTnxNA@public.gmane.org>
2013-03-05 22:05 ` Serge E. Hallyn
[not found] ` <20130307102352.4a5943cd@oracle.com>
[not found] ` <20130307102352.4a5943cd-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2013-03-07 21:54 ` Serge E. Hallyn
[not found] ` <20130307215457.GB9348-anj0Drq5vpzx6HRWoRZK3AC/G2K4zDHf@public.gmane.org>
2013-03-07 22:56 ` Eric W. Biederman
[not found] ` <876212rf9b.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-03-08 6:50 ` [Pkg-shadow-devel] " Christian PERRIER
[not found] ` <20130308065019.GI5885-FvNwPcshoeM/MCprI7ZU+I/wHUNs+SP4HZ5vskTnxNA@public.gmane.org>
2013-06-02 13:48 ` Serge E. Hallyn
[not found] ` <20130602134823.GB8004-anj0Drq5vpzx6HRWoRZK3AC/G2K4zDHf@public.gmane.org>
2013-06-02 14:04 ` Christian PERRIER
[not found] ` <20130602140436.GK9152-FvNwPcshoeM/MCprI7ZU+I/wHUNs+SP4HZ5vskTnxNA@public.gmane.org>
2013-06-02 14:33 ` Serge E. Hallyn
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