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-rw-r--r--geo-replication/src/gsyncd.c367
1 files changed, 367 insertions, 0 deletions
diff --git a/geo-replication/src/gsyncd.c b/geo-replication/src/gsyncd.c
new file mode 100644
index 0000000..9c4a5bd
--- /dev/null
+++ b/geo-replication/src/gsyncd.c
@@ -0,0 +1,367 @@
+/*
+ Copyright (c) 2011-2012 Red Hat, Inc. <http://www.redhat.com>
+ This file is part of GlusterFS.
+
+ This file is licensed to you under your choice of the GNU Lesser
+ General Public License, version 3 or any later version (LGPLv3 or
+ later), or the GNU General Public License, version 2 (GPLv2), in all
+ cases as published by the Free Software Foundation.
+*/
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/param.h> /* for PATH_MAX */
+
+/* NOTE (USE_LIBGLUSTERFS):
+ * ------------------------
+ * When USE_LIBGLUSTERFS debugging sumbol is passed; perform
+ * glusterfs translator like initialization so that glusterfs
+ * globals, contexts are valid when glustefs api's are invoked.
+ * We unconditionally pass then while building gsyncd binary.
+ */
+#ifdef USE_LIBGLUSTERFS
+#include "glusterfs.h"
+#include "globals.h"
+#endif
+
+#include "common-utils.h"
+#include "run.h"
+#include "procdiggy.h"
+
+#define _GLUSTERD_CALLED_ "_GLUSTERD_CALLED_"
+#define _GSYNCD_DISPATCHED_ "_GSYNCD_DISPATCHED_"
+#define GSYNCD_CONF "geo-replication/gsyncd.conf"
+#define GSYNCD_PY "gsyncd.py"
+#define RSYNC "rsync"
+
+int restricted = 0;
+
+static int
+duplexpand (void **buf, size_t tsiz, size_t *len)
+{
+ size_t osiz = tsiz * *len;
+ char *p = realloc (*buf, osiz << 1);
+ if (!p) {
+ free(*buf);
+ return -1;
+ }
+
+ memset (p + osiz, 0, osiz);
+ *buf = p;
+ *len <<= 1;
+
+ return 0;
+}
+
+static int
+str2argv (char *str, char ***argv)
+{
+ char *p = NULL;
+ char *savetok = NULL;
+ int argc = 0;
+ size_t argv_len = 32;
+ int ret = 0;
+
+ assert (str);
+ str = strdup (str);
+ if (!str)
+ return -1;
+
+ *argv = calloc (argv_len, sizeof (**argv));
+ if (!*argv)
+ goto error;
+
+ while ((p = strtok_r (str, " ", &savetok))) {
+ str = NULL;
+
+ argc++;
+ if (argc == argv_len) {
+ ret = duplexpand ((void *)argv,
+ sizeof (**argv),
+ &argv_len);
+ if (ret == -1)
+ goto error;
+ }
+ (*argv)[argc - 1] = p;
+ }
+
+ return argc;
+
+ error:
+ fprintf (stderr, "out of memory\n");
+ return -1;
+}
+
+static int
+invoke_gsyncd (int argc, char **argv)
+{
+ char config_file[PATH_MAX] = {0,};
+ size_t gluster_workdir_len = 0;
+ runner_t runner = {0,};
+ int i = 0;
+ int j = 0;
+ char *nargv[argc + 4];
+ char *python = NULL;
+
+ if (restricted) {
+ size_t len;
+ /* in restricted mode we forcibly use the system-wide config */
+ runinit (&runner);
+ runner_add_args (&runner, SBIN_DIR"/gluster",
+ "--log-file=-", "system::", "getwd",
+ NULL);
+ runner_redir (&runner, STDOUT_FILENO, RUN_PIPE);
+ if (runner_start (&runner) == 0 &&
+ fgets (config_file, PATH_MAX,
+ runner_chio (&runner, STDOUT_FILENO)) != NULL &&
+ (len = strlen (config_file)) &&
+ config_file[len - 1] == '\n' &&
+ runner_end (&runner) == 0)
+ gluster_workdir_len = len - 1;
+
+ if (gluster_workdir_len) {
+ if (gluster_workdir_len + 1 + strlen (GSYNCD_CONF) + 1 >
+ PATH_MAX)
+ goto error;
+ config_file[gluster_workdir_len] = '/';
+ strcat (config_file, GSYNCD_CONF);
+ } else
+ goto error;
+
+ if (setenv ("_GSYNCD_RESTRICTED_", "1", 1) == -1)
+ goto error;
+ }
+
+ if (chdir ("/") == -1)
+ goto error;
+
+ j = 0;
+ python = getenv("PYTHON");
+ if(!python)
+ python = PYTHON;
+ nargv[j++] = python;
+ nargv[j++] = GSYNCD_PREFIX"/python/syncdaemon/"GSYNCD_PY;
+ for (i = 1; i < argc; i++)
+ nargv[j++] = argv[i];
+ if (config_file[0]) {
+ nargv[j++] = "-c";
+ nargv[j++] = config_file;
+ }
+ nargv[j++] = NULL;
+
+ execvp (python, nargv);
+
+ fprintf (stderr, "exec of '%s' failed\n", python);
+ return 127;
+
+ error:
+ fprintf (stderr, "gsyncd initializaion failed\n");
+ return 1;
+}
+
+
+static int
+find_gsyncd (pid_t pid, pid_t ppid, char *name, void *data)
+{
+ char buf[NAME_MAX * 2] = {0,};
+ char path[PATH_MAX] = {0,};
+ char *p = NULL;
+ int zeros = 0;
+ int ret = 0;
+ int fd = -1;
+ pid_t *pida = (pid_t *)data;
+
+ if (ppid != pida[0])
+ return 0;
+
+ sprintf (path, PROC"/%d/cmdline", pid);
+ fd = open (path, O_RDONLY);
+ if (fd == -1)
+ return 0;
+ ret = read (fd, buf, sizeof (buf));
+ close (fd);
+ if (ret == -1)
+ return 0;
+ for (zeros = 0, p = buf; zeros < 2 && p < buf + ret; p++)
+ zeros += !*p;
+
+ ret = 0;
+ switch (zeros) {
+ case 2:
+ if ((strcmp (basename (buf), basename (PYTHON)) ||
+ strcmp (basename (buf + strlen (buf) + 1), GSYNCD_PY)) == 0) {
+ ret = 1;
+ break;
+ }
+ /* fallthrough */
+ case 1:
+ if (strcmp (basename (buf), GSYNCD_PY) == 0)
+ ret = 1;
+ }
+
+ if (ret == 1) {
+ if (pida[1] != -1) {
+ fprintf (stderr, GSYNCD_PY" sibling is not unique");
+ return -1;
+ }
+ pida[1] = pid;
+ }
+
+ return 0;
+}
+
+static int
+invoke_rsync (int argc, char **argv)
+{
+ int i = 0;
+ char path[PATH_MAX] = {0,};
+ pid_t pid = -1;
+ pid_t ppid = -1;
+ pid_t pida[] = {-1, -1};
+ char *name = NULL;
+ char buf[PATH_MAX + 1] = {0,};
+ int ret = 0;
+
+ assert (argv[argc] == NULL);
+
+ if (argc < 2 || strcmp (argv[1], "--server") != 0)
+ goto error;
+
+ for (i = 2; i < argc && argv[i][0] == '-'; i++);
+
+ if (!(i == argc - 2 && strcmp (argv[i], ".") == 0 && argv[i + 1][0] == '/')) {
+ fprintf (stderr, "need an rsync invocation without protected args\n");
+ goto error;
+ }
+
+ /* look up sshd we are spawned from */
+ for (pid = getpid () ;; pid = ppid) {
+ ppid = pidinfo (pid, &name);
+ if (ppid < 0) {
+ fprintf (stderr, "sshd ancestor not found\n");
+ goto error;
+ }
+ if (strcmp (name, "sshd") == 0) {
+ GF_FREE (name);
+ break;
+ }
+ GF_FREE (name);
+ }
+ /* look up "ssh-sibling" gsyncd */
+ pida[0] = pid;
+ ret = prociter (find_gsyncd, pida);
+ if (ret == -1 || pida[1] == -1) {
+ fprintf (stderr, "gsyncd sibling not found\n");
+ goto error;
+ }
+ /* check if rsync target matches gsyncd target */
+ sprintf (path, PROC"/%d/cwd", pida[1]);
+ ret = readlink (path, buf, sizeof (buf));
+ if (ret == -1 || ret == sizeof (buf))
+ goto error;
+ if (strcmp (argv[argc - 1], "/") == 0 /* root dir cannot be a target */ ||
+ (strcmp (argv[argc - 1], path) /* match against gluster target */ &&
+ strcmp (argv[argc - 1], buf) /* match against file target */) != 0) {
+ fprintf (stderr, "rsync target does not match "GEOREP" session\n");
+ goto error;
+ }
+
+ argv[0] = RSYNC;
+
+ execvp (RSYNC, argv);
+
+ fprintf (stderr, "exec of "RSYNC" failed\n");
+ return 127;
+
+ error:
+ fprintf (stderr, "disallowed "RSYNC" invocation\n");
+ return 1;
+}
+
+
+struct invocable {
+ char *name;
+ int (*invoker) (int argc, char **argv);
+};
+
+struct invocable invocables[] = {
+ { "rsync", invoke_rsync },
+ { "gsyncd", invoke_gsyncd },
+ { NULL, NULL}
+};
+
+int
+main (int argc, char **argv)
+{
+ char *evas = NULL;
+ struct invocable *i = NULL;
+ char *b = NULL;
+ char *sargv = NULL;
+
+#ifdef USE_LIBGLUSTERFS
+ glusterfs_ctx_t *ctx = NULL;
+
+ ctx = glusterfs_ctx_new ();
+ if (!ctx)
+ return ENOMEM;
+
+ if (glusterfs_globals_init (ctx))
+ return 1;
+
+ THIS->ctx = ctx;
+#endif
+
+ evas = getenv (_GLUSTERD_CALLED_);
+ if (evas && strcmp (evas, "1") == 0)
+ /* OK, we know glusterd called us, no need to look for further config
+ * ... altough this conclusion should not inherit to our children
+ */
+ unsetenv (_GLUSTERD_CALLED_);
+ else {
+ /* we regard all gsyncd invocations unsafe
+ * that do not come from glusterd and
+ * therefore restrict it
+ */
+ restricted = 1;
+
+ if (!getenv (_GSYNCD_DISPATCHED_)) {
+ evas = getenv ("SSH_ORIGINAL_COMMAND");
+ if (evas)
+ sargv = evas;
+ else {
+ evas = getenv ("SHELL");
+ if (evas && strcmp (basename (evas), "gsyncd") == 0 &&
+ argc == 3 && strcmp (argv[1], "-c") == 0)
+ sargv = argv[2];
+ }
+ }
+
+ }
+
+ if (!(sargv && restricted))
+ return invoke_gsyncd (argc, argv);
+
+ argc = str2argv (sargv, &argv);
+ if (argc == -1 || setenv (_GSYNCD_DISPATCHED_, "1", 1) == -1) {
+ fprintf (stderr, "internal error\n");
+ return 1;
+ }
+
+ b = basename (argv[0]);
+ for (i = invocables; i->name; i++) {
+ if (strcmp (b, i->name) == 0)
+ return i->invoker (argc, argv);
+ }
+
+ fprintf (stderr, "invoking %s in restricted SSH session is not allowed\n",
+ b);
+
+ return 1;
+}