From 03f539c766780a083010636cc67f96fcb2bab30f Mon Sep 17 00:00:00 2001

From: Karel Zak <kzak@redhat.com>

Date: Fri, 24 Jun 2016 12:16:24 +0200

Subject: [PATCH 76/84] lsns: backport new command

Addresses: http://bugzilla.redhat.com/show_bug.cgi?id=1332084

Signed-off-by: Karel Zak <kzak@redhat.com>

---

 bash-completion/lsns    |  55 ++++

 configure.ac            |   6 +

 include/Makemodule.am   |   1 +

 include/c.h             |   8 +

 include/debug.h         |   2 +-

 include/idcache.h       |  28 ++

 include/procutils.h     |   2 +

 lib/Makemodule.am       |   1 +

 lib/idcache.c           | 117 ++++++++

 lib/procutils.c         |  43 +++

 sys-utils/Makemodule.am |   7 +

 sys-utils/lsns.8        |  78 +++++

 sys-utils/lsns.c        | 748 ++++++++++++++++++++++++++++++++++++++++++++++++

 13 files changed, 1095 insertions(+), 1 deletion(-)

 create mode 100644 bash-completion/lsns

 create mode 100644 include/idcache.h

 create mode 100644 lib/idcache.c

 create mode 100644 sys-utils/lsns.8

 create mode 100644 sys-utils/lsns.c

diff --git a/bash-completion/lsns b/bash-completion/lsns

new file mode 100644

index 0000000..d02df3b

--- /dev/null

+++ b/bash-completion/lsns

@@ -0,0 +1,55 @@

+_lsns_module()

+{

+	local cur prev OPTS LSNS_COLS_ALL

+	COMPREPLY=()

+	cur="${COMP_WORDS[COMP_CWORD]}"

+	prev="${COMP_WORDS[COMP_CWORD-1]}"

+	LSNS_COLS_ALL="

+		NS TYPE PATH NPROCS PID PPID COMMAND UID USER

+	"

+	case $prev in

+		'-o'|'--output')

+			local prefix realcur LSNS_COLS

+			realcur="${cur##*,}"

+			prefix="${cur%$realcur}"

+			for WORD in $LSNS_COLS_ALL; do

+				if ! [[ $prefix == *"$WORD"* ]]; then

+					LSNS_COLS="$WORD $LSNS_COLS"

+				fi

+			done

+			compopt -o nospace

+			COMPREPLY=( $(compgen -P "$prefix" -W "$LSNS_COLS" -S ',' -- $realcur) )

+			return 0

+			;;

+		'-p'|'--task')

+			COMPREPLY=( $(compgen -W "$(cd /proc && echo [0-9]*)" -- $cur) )

+			return 0

+			;;

+		'-t'|'--type')

+			COMPREPLY=( $(compgen -W "mnt net ipc user pid uts" -- $cur) )

+			return 0

+			;;

+		'-h'|'--help'|'-V'|'--version')

+			return 0

+			;;

+	esac

+	case $cur in

+		-*)

+			COMPREPLY=( $(compgen -W "

+					--list

+					--noheadings

+					--output

+					--task

+					--raw

+					--notruncate

+					--type

+					--help

+					--version

+				" -- $cur) )

+			return 0

+			;;

+	esac

+	COMPREPLY=( $(compgen -W "mnt net pid uts ipc user" -- $cur ) )

+	return 0

+}

+complete -F _lsns_module lsns

diff --git a/configure.ac b/configure.ac

index f3c7214..5d9ea39 100644

--- a/configure.ac

+++ b/configure.ac

@@ -1032,6 +1032,12 @@ UL_REQUIRES_BUILD([lslogins], [libsmartcols])

 AM_CONDITIONAL([BUILD_LSLOGINS], [test "x$build_lslogins" = xyes])

+UL_BUILD_INIT([lsns], [check])

+UL_REQUIRES_LINUX([lsns])

+UL_REQUIRES_BUILD([lsns], [libsmartcols])

+AM_CONDITIONAL([BUILD_LSNS], [test "x$build_lsns" = xyes])

+

+

 UL_BUILD_INIT([chcpu], [check])

 UL_REQUIRES_LINUX([chcpu])

 UL_REQUIRES_HAVE([chcpu], [cpu_set_t], [cpu_set_t type])

diff --git a/include/Makemodule.am b/include/Makemodule.am

index 7b53244..757f317 100644

--- a/include/Makemodule.am

+++ b/include/Makemodule.am

@@ -15,6 +15,7 @@ dist_noinst_HEADERS += \

 	include/exec_shell.h \

 	include/exitcodes.h \

 	include/fileutils.h \

+	include/idcache.h \

 	include/ismounted.h \

 	include/linux_reboot.h \

 	include/linux_version.h \

diff --git a/include/c.h b/include/c.h

index 7b59ce8..a2779a5 100644

--- a/include/c.h

+++ b/include/c.h

@@ -110,6 +110,14 @@

 	_max1 > _max2 ? _max1 : _max2; })

 #endif

+#ifndef cmp_numbers

+# define cmp_numbers(x, y) __extension__ ({	\

+	__typeof__(x) _a = (x);			\

+	__typeof__(y) _b = (y);			\

+	(void) (&_a == &_b);			\

+	_a == _b ? 0 : _a > _b ? 1 : -1; })

+#endif

+

 #ifndef offsetof

 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)

 #endif

diff --git a/include/debug.h b/include/debug.h

index 25045aa..848e474 100644

--- a/include/debug.h

+++ b/include/debug.h

@@ -15,7 +15,7 @@ struct dbg_mask { char *mname; int val; };

 #define UL_DEBUG_DEFINE_MASK(m) int m ## _debug_mask

 #define UL_DEBUG_DECLARE_MASK(m) extern UL_DEBUG_DEFINE_MASK(m)

-#define UL_DEBUG_DEFINE_MASKANEMS(m) static const struct dbg_mask m ## _masknames[]

+#define UL_DEBUG_DEFINE_MASKNAMES(m) static const struct dbg_mask m ## _masknames[]

 /* p - flag prefix, m - flag postfix */

 #define UL_DEBUG_DEFINE_FLAG(p, m) p ## m

diff --git a/include/idcache.h b/include/idcache.h

new file mode 100644

index 0000000..912edd5

--- /dev/null

+++ b/include/idcache.h

@@ -0,0 +1,28 @@

+#ifndef UTIL_LINUX_IDCACHE_H

+#define UTIL_LINUX_IDCACHE_H

+

+#include <sys/types.h>

+#include <pwd.h>

+

+#define IDCACHE_FLAGS_NAMELEN	(1 << 1)

+

+struct identry {

+	unsigned long int	id;

+	char			*name;

+	struct identry		*next;

+};

+

+struct idcache {

+	struct identry	*ent;	/* first entry */

+	int		width;	/* name width */

+};

+

+

+extern struct idcache *new_idcache(void);

+extern void add_gid(struct idcache *cache, unsigned long int id);

+extern void add_uid(struct idcache *cache, unsigned long int id);

+

+extern void free_idcache(struct idcache *ic);

+extern struct identry *get_id(struct idcache *ic, unsigned long int id);

+

+#endif /* UTIL_LINUX_IDCACHE_H */

diff --git a/include/procutils.h b/include/procutils.h

index 14b766c..9f8dd76 100644

--- a/include/procutils.h

+++ b/include/procutils.h

@@ -28,5 +28,7 @@ extern void proc_processes_filter_by_name(struct proc_processes *ps, const char

 extern void proc_processes_filter_by_uid(struct proc_processes *ps, uid_t uid);

 extern int proc_next_pid(struct proc_processes *ps, pid_t *pid);

+extern char *proc_get_command(pid_t pid);

+extern char *proc_get_command_name(pid_t pid);

 #endif /* UTIL_LINUX_PROCUTILS */

diff --git a/lib/Makemodule.am b/lib/Makemodule.am

index eed31f1..73280f9 100644

--- a/lib/Makemodule.am

+++ b/lib/Makemodule.am

@@ -8,6 +8,7 @@ libcommon_la_SOURCES = \

 	lib/colors.c \

 	lib/crc32.c \

 	lib/env.c \

+	lib/idcache.c \

 	lib/fileutils.c \

 	lib/ismounted.c \

 	lib/mangle.c \

diff --git a/lib/idcache.c b/lib/idcache.c

new file mode 100644

index 0000000..3c358b8

--- /dev/null

+++ b/lib/idcache.c

@@ -0,0 +1,117 @@

+

+#include <wchar.h>

+#include <pwd.h>

+#include <grp.h>

+#include <sys/types.h>

+

+#include "c.h"

+#include "idcache.h"

+

+#ifndef LOGIN_NAME_MAX

+#define LOGIN_NAME_MAX 256

+#endif

+

+struct identry *get_id(struct idcache *ic, unsigned long int id)

+{

+	struct identry *ent;

+

+	if (!ic)

+		return NULL;

+

+	for (ent = ic->ent; ent; ent = ent->next) {

+		if (ent->id == id)

+			return ent;

+	}

+

+	return NULL;

+}

+

+struct idcache *new_idcache()

+{

+	return calloc(1, sizeof(struct idcache));

+}

+

+void free_idcache(struct idcache *ic)

+{

+	struct identry *ent = ic->ent;

+

+	while (ent) {

+		struct identry *next = ent->next;

+		free(ent->name);

+		free(ent);

+		ent = next;

+	}

+

+	free(ic);

+}

+

+static void add_id(struct idcache *ic, char *name, unsigned long int id)

+{

+	struct identry *ent, *x;

+	int w = 0;

+

+	ent = calloc(1, sizeof(struct identry));

+	if (!ent)

+		return;

+	ent->id = id;

+

+	if (name) {

+#ifdef HAVE_WIDECHAR

+		wchar_t wc[LOGIN_NAME_MAX + 1];

+

+		if (mbstowcs(wc, name, LOGIN_NAME_MAX) > 0) {

+			wc[LOGIN_NAME_MAX] = '\0';

+			w = wcswidth(wc, LOGIN_NAME_MAX);

+		}

+		else

+#endif

+			w = strlen(name);

+	}

+

+	/* note, we ignore names with non-printable widechars */

+	if (w > 0) {

+		ent->name = strdup(name);

+		if (!ent->name) {

+			free(ent);

+			return;

+		}

+	} else {

+		if (asprintf(&ent->name, "%lu", id) < 0) {

+			free(ent);

+			return;

+		}

+	}

+

+	for (x = ic->ent; x && x->next; x = x->next);

+

+	if (x)

+		x->next = ent;

+	else

+		ic->ent = ent;

+

+	if (w <= 0)

+		w = ent->name ? strlen(ent->name) : 0;

+	ic->width = ic->width < w ? w : ic->width;

+	return;

+}

+

+void add_uid(struct idcache *cache, unsigned long int id)

+{

+	struct identry *ent= get_id(cache, id);

+

+	if (!ent) {

+		struct passwd *pw = getpwuid((uid_t) id);

+		add_id(cache, pw ? pw->pw_name : NULL, id);

+	}

+}

+

+void add_gid(struct idcache *cache, unsigned long int id)

+{

+	struct identry *ent = get_id(cache, id);

+

+	if (!ent) {

+		struct group *gr = getgrgid((gid_t) id);

+		add_id(cache, gr ? gr->gr_name : NULL, id);

+	}

+}

+

diff --git a/lib/procutils.c b/lib/procutils.c

index d633261..8dfdec9 100644

--- a/lib/procutils.c

+++ b/lib/procutils.c

@@ -25,6 +25,7 @@

 #include "procutils.h"

 #include "at.h"

 #include "c.h"

+#include "all-io.h"

 /*

  * @pid: process ID for which we want to obtain the threads group

@@ -193,6 +194,48 @@ int proc_next_pid(struct proc_processes *ps, pid_t *pid)

 	return 0;

 }

+/* returns process command path, use free() for result */

+static char *proc_file_strdup(pid_t pid, const char *name)

+{

+	char buf[BUFSIZ], *res = NULL;

+	ssize_t sz = 0;

+	size_t i;

+	int fd;

+

+	snprintf(buf, sizeof(buf), "/proc/%d/%s", (int) pid, name);

+	fd = open(buf, O_RDONLY);

+	if (fd < 0)

+		goto done;

+

+	sz = read_all(fd, buf, sizeof(buf));

+	if (sz <= 0)

+		goto done;

+

+	for (i = 0; i < (size_t) sz; i++) {

+

+		if (buf[i] == '\0')

+			buf[i] = ' ';

+	}

+	buf[sz - 1] = '\0';

+	res = strdup(buf);

+done:

+	if (fd >= 0)

+		close(fd);

+	return res;

+}

+

+/* returns process command path, use free() for result */

+char *proc_get_command(pid_t pid)

+{

+	return proc_file_strdup(pid, "cmdline");

+}

+

+/* returns process command name, use free() for result */

+char *proc_get_command_name(pid_t pid)

+{

+	return proc_file_strdup(pid, "comm");

+}

+

 #ifdef TEST_PROGRAM

 static int test_tasks(int argc, char *argv[])

diff --git a/sys-utils/Makemodule.am b/sys-utils/Makemodule.am

index c6c561c..9baf5a3 100644

--- a/sys-utils/Makemodule.am

+++ b/sys-utils/Makemodule.am

@@ -182,6 +182,13 @@ prlimit_SOURCES = sys-utils/prlimit.c

 prlimit_LDADD = $(LDADD) libcommon.la

 endif

+if BUILD_LSNS

+usrbin_exec_PROGRAMS += lsns

+dist_man_MANS += sys-utils/lsns.8

+lsns_SOURCES =	sys-utils/lsns.c

+lsns_LDADD = $(LDADD) libcommon.la libsmartcols.la

+lsns_CFLAGS = $(AM_CFLAGS) -I$(ul_libsmartcols_incdir)

+endif

 if BUILD_MOUNT

 #

diff --git a/sys-utils/lsns.8 b/sys-utils/lsns.8

new file mode 100644

index 0000000..328df47

--- /dev/null

+++ b/sys-utils/lsns.8

@@ -0,0 +1,78 @@

+.\" Man page for the lsns command.

+.\" Copyright 2015 Karel Zak <kzak@redhat.com>

+.\" May be distributed under the GNU General Public License

+

+.TH LSNS 8 "December 2015" "util-linux" "System Administration"

+.SH NAME

+lsns \- list namespaces

+.SH SYNOPSIS

+.B lsns

+[options]

+.RI [ namespace ]

+

+.SH DESCRIPTION

+.B lsns

+lists information about all the currently accessible namespaces or about the

+given \fInamespace\fP.  The \fInamespace\fP identifier is an inode number.

+

+The default output is subject to change.  So whenever possible, you should

+avoid using default outputs in your scripts.  Always explicitly define expected

+columns by using the \fB\-\-output\fR option together with a columns list in

+environments where a stable output is required.

+

+Note that \fBlsns\fR reads information directly from the /proc filesystem and

+for non-root users it may return incomplete information.  The current /proc

+filesystem may be unshared and affected by a PID namespace

+(see \fBunshare \-\-mount\-proc\fP for more details).

+.B lsns

+is not able to see persistent namespaces without processes where the namespace

+instance is held by a bind mount to /proc/\fIpid\fR/ns/\fItype\fR.

+

+.SH OPTIONS

+.TP

+.BR \-l , " \-\-list"

+Use list output format.

+.TP

+.BR \-n , " \-\-noheadings"

+Do not print a header line.

+.TP

+.BR \-o , " \-\-output " \fIlist\fP

+Specify which output columns to print.  Use \fB\-\-help\fR

+to get a list of all supported columns.

+

+The default list of columns may be extended if \fIlist\fP is

+specified in the format \fB+\fIlist\fP (e.g. \fBlsns \-o +PATH\fP).

+.TP

+.BR \-p , " \-\-task " \fIpid\fP

+Display only the namespaces held by the process with this \fIpid\fR.

+.TP

+.BR \-r , " \-\-raw"

+Use the raw output format.

+.TP

+.BR \-t , " \-\-type " \fItype\fP

+Display the specified \fItype\fP of namespaces only.  The supported types are

+\fBmnt\fP, \fBnet\fP, \fBipc\fP, \fBuser\fP, \fBpid\fP and \fButs\fP.  This

+option may be given more than once.

+.TP

+.BR \-u , " \-\-notruncate"

+Do not truncate text in columns.

+.TP

+.BR \-V , " \-\-version"

+Display version information and exit.

+.TP

+.BR \-h , " \-\-help"

+Display help text and exit.

+

+.SH AUTHORS

+.nf

+Karel Zak <kzak@redhat.com>

+.fi

+

+.SH "SEE ALSO"

+.BR unshare (1),

+.BR nsenter (1),

+.BR clone (2)

+

+.SH AVAILABILITY

+The lsns command is part of the util-linux package and is available from

+ftp://ftp.kernel.org/pub/linux/utils/util-linux/.

diff --git a/sys-utils/lsns.c b/sys-utils/lsns.c

new file mode 100644

index 0000000..5ee2981

--- /dev/null

+++ b/sys-utils/lsns.c

@@ -0,0 +1,748 @@

+/*

+ * lsns(8) - list system namespaces

+ *

+ * Copyright (C) 2015 Karel Zak <kzak@redhat.com>

+ *

+ * This program is free software; you can redistribute it and/or modify

+ * it under the terms of the GNU General Public License as published by

+ * the Free Software Foundation; either version 2 of the License, or

+ * (at your option) any later version.

+ *

+ * This program is distributed in the hope that it would be useful,

+ * but WITHOUT ANY WARRANTY; without even the implied warranty of

+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+ * GNU General Public License for more details.

+ *

+ * You should have received a copy of the GNU General Public License

+ * along with this program; if not, write to the Free Software Foundation,

+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

+ */

+#include <stdio.h>

+#include <string.h>

+#include <getopt.h>

+#include <stdlib.h>

+#include <assert.h>

+#include <dirent.h>

+#include <unistd.h>

+#include <sys/stat.h>

+#include <sys/types.h>

+#include <wchar.h>

+#include <libsmartcols.h>

+

+#include "pathnames.h"

+#include "nls.h"

+#include "xalloc.h"

+#include "c.h"

+#include "list.h"

+#include "closestream.h"

+#include "optutils.h"

+#include "procutils.h"

+#include "strutils.h"

+#include "namespace.h"

+#include "path.h"

+#include "idcache.h"

+

+#include "debug.h"

+

+UL_DEBUG_DEFINE_MASK(lsns);

+UL_DEBUG_DEFINE_MASKNAMES(lsns) = UL_DEBUG_EMPTY_MASKNAMES;

+

+#define LSNS_DEBUG_INIT		(1 << 1)

+#define LSNS_DEBUG_PROC		(1 << 2)

+#define LSNS_DEBUG_NS		(1 << 3)

+#define LSNS_DEBUG_ALL		0xFFFF

+

+#define DBG(m, x)       __UL_DBG(lsns, LSNS_DEBUG_, m, x)

+#define ON_DBG(m, x)    __UL_DBG_CALL(lsns, LSNS_DEBUG_, m, x)

+

+struct idcache *uid_cache = NULL;

+

+/* column IDs */

+enum {

+	COL_NS = 0,

+	COL_TYPE,

+	COL_PATH,

+	COL_NPROCS,

+	COL_PID,

+	COL_PPID,

+	COL_COMMAND,

+	COL_UID,

+	COL_USER

+};

+

+/* column names */

+struct colinfo {

+	const char *name; /* header */

+	double	   whint; /* width hint (N < 1 is in percent of termwidth) */

+	int	   flags; /* SCOLS_FL_* */

+	const char *help;

+};

+

+/* columns descriptions */

+static const struct colinfo infos[] = {

+	[COL_NS]      = { "NS",     10, SCOLS_FL_RIGHT, N_("namespace identifier (inode number)") },

+	[COL_TYPE]    = { "TYPE",    5, 0, N_("kind of namespace") },

+	[COL_PATH]    = { "PATH",    0, 0, N_("path to the namespace")},

+	[COL_NPROCS]  = { "NPROCS",  5, SCOLS_FL_RIGHT, N_("number of processes in the namespace") },

+	[COL_PID]     = { "PID",     5, SCOLS_FL_RIGHT, N_("lowest PID in the namespace") },

+	[COL_PPID]    = { "PPID",    5, SCOLS_FL_RIGHT, N_("PPID of the PID") },

+	[COL_COMMAND] = { "COMMAND", 0, SCOLS_FL_TRUNC, N_("command line of the PID")},

+	[COL_UID]     = { "UID",     0, SCOLS_FL_RIGHT, N_("UID of the PID")},

+	[COL_USER]    = { "USER",    0, 0, N_("username of the PID")}

+};

+

+static int columns[ARRAY_SIZE(infos) * 2];

+static size_t ncolumns;

+

+enum {

+	LSNS_ID_MNT = 0,

+	LSNS_ID_NET,

+	LSNS_ID_PID,

+	LSNS_ID_UTS,

+	LSNS_ID_IPC,

+	LSNS_ID_USER

+};

+

+static char *ns_names[] = {

+	[LSNS_ID_MNT] = "mnt",

+	[LSNS_ID_NET] = "net",

+	[LSNS_ID_PID] = "pid",

+	[LSNS_ID_UTS] = "uts",

+	[LSNS_ID_IPC] = "ipc",

+	[LSNS_ID_USER] = "user"

+};

+

+struct lsns_namespace {

+	ino_t id;

+	int type;			/* LSNS_* */

+	int nprocs;

+

+	struct lsns_process *proc;

+

+	struct list_head namespaces;	/* lsns->processes member */

+	struct list_head processes;	/* head of lsns_process *siblings */

+};

+

+struct lsns_process {

+	pid_t pid;		/* process PID */

+	pid_t ppid;		/* parent's PID */

+	pid_t tpid;		/* thread group */

+	char state;

+	uid_t uid;

+

+	ino_t            ns_ids[ARRAY_SIZE(ns_names)];

+	struct list_head ns_siblings[ARRAY_SIZE(ns_names)];

+

+	struct list_head processes;	/* list of processes */

+

+	struct libscols_line *outline;

+	struct lsns_process *parent;

+};

+

+struct lsns {

+	struct list_head processes;

+	struct list_head namespaces;

+

+	pid_t	fltr_pid;	/* filter out by PID */

+	ino_t	fltr_ns;	/* filter out by namespace */

+	int	fltr_types[ARRAY_SIZE(ns_names)];

+	int	fltr_ntypes;

+

+	unsigned int raw	: 1,

+		     tree	: 1,

+		     list	: 1,

+		     notrunc	: 1,

+		     no_headings: 1;

+};

+

+static void lsns_init_debug(void)

+{

+	__UL_INIT_DEBUG(lsns, LSNS_DEBUG_, 0, LSNS_DEBUG);

+}

+

+static int ns_name2type(const char *name)

+{

+	size_t i;

+

+	for (i = 0; i < ARRAY_SIZE(ns_names); i++) {

+		if (strcmp(ns_names[i], name) == 0)

+			return i;

+	}

+	return -1;

+}

+

+static int column_name_to_id(const char *name, size_t namesz)

+{

+	size_t i;

+

+	assert(name);

+

+	for (i = 0; i < ARRAY_SIZE(infos); i++) {

+		const char *cn = infos[i].name;

+

+		if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))

+			return i;

+	}

+	warnx(_("unknown column: %s"), name);

+	return -1;

+}

+

+static inline int get_column_id(int num)

+{

+	assert(num >= 0);

+	assert((size_t) num < ncolumns);

+	assert(columns[num] < (int) ARRAY_SIZE(infos));

+

+	return columns[num];

+}

+

+static inline const struct colinfo *get_column_info(unsigned num)

+{

+	return &infos[ get_column_id(num) ];

+}

+

+static ino_t get_ns_ino(int dir, const char *nsname, ino_t *ino)

+{

+	struct stat st;

+	char path[16];

+

+	snprintf(path, sizeof(path), "ns/%s", nsname);

+

+	if (fstatat(dir, path, &st, 0) != 0)

+		return -errno;

+	*ino = st.st_ino;

+	return 0;

+}

+

+

+static int read_process(struct lsns *ls, pid_t pid)

+{