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/*
* Copyright 2004-2025 the Pacemaker project contributors
*
* The version control history for this file may have further details.
*
* This source code is licensed under the GNU General Public License version 2
* or later (GPLv2+) WITHOUT ANY WARRANTY.
*/
#include <crm_internal.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <dirent.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <glib.h>
#include <libxml/tree.h>
#include <crm/crm.h>
#include <crm/cib.h>
#include <crm/common/util.h>
#include <crm/common/xml.h>
#include <crm/cib/internal.h>
#include <crm/cluster.h>
#include <pacemaker-based.h>
crm_trigger_t *cib_writer = NULL;
int write_cib_contents(gpointer p);
static void
cib_rename(const char *old)
{
int new_fd;
char *new = crm_strdup_printf("%s/cib.auto.XXXXXX", cib_root);
umask(S_IWGRP | S_IWOTH | S_IROTH);
new_fd = mkstemp(new);
if ((new_fd < 0) || (rename(old, new) < 0)) {
crm_err("Couldn't archive unusable file %s (disabling disk writes and continuing)",
old);
cib_writes_enabled = FALSE;
} else {
crm_err("Archived unusable file %s as %s", old, new);
}
if (new_fd > 0) {
close(new_fd);
}
free(new);
}
/*
* It is the callers responsibility to free the output of this function
*/
static xmlNode *
retrieveCib(const char *filename, const char *sigfile)
{
xmlNode *root = NULL;
int rc = cib_file_read_and_verify(filename, sigfile, &root);
if (rc == pcmk_ok) {
crm_info("Loaded CIB from %s (with digest %s)", filename, sigfile);
} else {
crm_warn("Continuing but NOT using CIB from %s (with digest %s): %s",
filename, sigfile, pcmk_strerror(rc));
if (rc == -pcmk_err_cib_modified) {
// Archive the original files so the contents are not lost
cib_rename(filename);
cib_rename(sigfile);
}
}
return root;
}
static int cib_archive_filter(const struct dirent * a)
{
int rc = 0;
// Looking for regular files starting with "cib-" and not ending in .sig
struct stat s;
char *a_path = crm_strdup_printf("%s/%s", cib_root, a->d_name);
if(stat(a_path, &s) != 0) {
rc = errno;
crm_trace("%s - stat failed: %s (%d)", a->d_name, pcmk_rc_str(rc), rc);
rc = 0;
} else if (!S_ISREG(s.st_mode)) {
crm_trace("%s - wrong type (%#o)",
a->d_name, (unsigned int) (s.st_mode & S_IFMT));
} else if(strstr(a->d_name, "cib-") != a->d_name) {
crm_trace("%s - wrong prefix", a->d_name);
} else if (pcmk__ends_with_ext(a->d_name, ".sig")) {
crm_trace("%s - wrong suffix", a->d_name);
} else {
crm_debug("%s - candidate", a->d_name);
rc = 1;
}
free(a_path);
return rc;
}
static int cib_archive_sort(const struct dirent ** a, const struct dirent **b)
{
/* Order by creation date - most recently created file first */
int rc = 0;
struct stat buf;
time_t a_age = 0;
time_t b_age = 0;
char *a_path = crm_strdup_printf("%s/%s", cib_root, a[0]->d_name);
char *b_path = crm_strdup_printf("%s/%s", cib_root, b[0]->d_name);
if(stat(a_path, &buf) == 0) {
a_age = buf.st_ctime;
}
if(stat(b_path, &buf) == 0) {
b_age = buf.st_ctime;
}
free(a_path);
free(b_path);
if(a_age > b_age) {
rc = 1;
} else if(a_age < b_age) {
rc = -1;
}
crm_trace("%s (%lu) vs. %s (%lu) : %d",
a[0]->d_name, (unsigned long)a_age,
b[0]->d_name, (unsigned long)b_age, rc);
return rc;
}
xmlNode *
readCibXmlFile(const char *dir, const char *file, gboolean discard_status)
{
struct dirent **namelist = NULL;
int lpc = 0;
char *sigfile = NULL;
char *sigfilepath = NULL;
char *filename = NULL;
const char *name = NULL;
const char *value = NULL;
const char *use_valgrind = pcmk__env_option(PCMK__ENV_VALGRIND_ENABLED);
xmlNode *root = NULL;
xmlNode *status = NULL;
sigfile = crm_strdup_printf("%s.sig", file);
if (pcmk__daemon_can_write(dir, file) == FALSE
|| pcmk__daemon_can_write(dir, sigfile) == FALSE) {
cib_status = -EACCES;
return NULL;
}
filename = crm_strdup_printf("%s/%s", dir, file);
sigfilepath = crm_strdup_printf("%s/%s", dir, sigfile);
free(sigfile);
cib_status = pcmk_ok;
root = retrieveCib(filename, sigfilepath);
free(filename);
free(sigfilepath);
if (root == NULL) {
lpc = scandir(cib_root, &namelist, cib_archive_filter, cib_archive_sort);
if (lpc < 0) {
crm_err("Could not check for CIB backups in %s: %s",
cib_root, pcmk_rc_str(errno));
}
}
while (root == NULL && lpc > 1) {
int rc = pcmk_ok;
lpc--;
filename = crm_strdup_printf("%s/%s", cib_root, namelist[lpc]->d_name);
sigfile = crm_strdup_printf("%s.sig", filename);
rc = cib_file_read_and_verify(filename, sigfile, &root);
if (rc == pcmk_ok) {
crm_notice("Loaded CIB from last valid backup %s (with digest %s)",
filename, sigfile);
} else {
crm_warn("Not using next most recent CIB backup from %s "
"(with digest %s): %s",
filename, sigfile, pcmk_strerror(rc));
}
free(namelist[lpc]);
free(filename);
free(sigfile);
}
free(namelist);
if (root == NULL) {
root = createEmptyCib(0);
crm_warn("Continuing with an empty configuration");
}
if (cib_writes_enabled && (use_valgrind != NULL)
&& (crm_is_true(use_valgrind)
|| (strstr(use_valgrind, PCMK__SERVER_BASED) != NULL))) {
cib_writes_enabled = FALSE;
crm_err("*** Disabling disk writes to avoid confusing Valgrind ***");
}
status = pcmk__xe_first_child(root, PCMK_XE_STATUS, NULL, NULL);
if (discard_status && status != NULL) {
// Strip out the PCMK_XE_STATUS section if there is one
pcmk__xml_free(status);
status = NULL;
}
if (status == NULL) {
pcmk__xe_create(root, PCMK_XE_STATUS);
}
/* Do this before schema validation happens */
/* fill in some defaults */
value = crm_element_value(root, PCMK_XA_ADMIN_EPOCH);
if (value == NULL) { // Not possible with schema validation enabled
crm_warn("Defaulting missing " PCMK_XA_ADMIN_EPOCH " to 0, but "
"cluster may get confused about which node's configuration "
"is most recent");
crm_xml_add_int(root, PCMK_XA_ADMIN_EPOCH, 0);
}
name = PCMK_XA_EPOCH;
value = crm_element_value(root, name);
if (value == NULL) {
crm_xml_add_int(root, name, 0);
}
name = PCMK_XA_NUM_UPDATES;
value = crm_element_value(root, name);
if (value == NULL) {
crm_xml_add_int(root, name, 0);
}
// Unset (DC should set appropriate value)
pcmk__xe_remove_attr(root, PCMK_XA_DC_UUID);
if (discard_status) {
crm_log_xml_trace(root, "[on-disk]");
}
if (!pcmk__configured_schema_validates(root)) {
cib_status = -pcmk_err_schema_validation;
}
return root;
}
gboolean
uninitializeCib(void)
{
xmlNode *tmp_cib = the_cib;
if (tmp_cib == NULL) {
return FALSE;
}
the_cib = NULL;
pcmk__xml_free(tmp_cib);
return TRUE;
}
/*
* This method will free the old CIB pointer on success and the new one
* on failure.
*/
int
activateCibXml(xmlNode * new_cib, gboolean to_disk, const char *op)
{
if (new_cib) {
xmlNode *saved_cib = the_cib;
pcmk__assert(new_cib != saved_cib);
the_cib = new_cib;
pcmk__xml_free(saved_cib);
if (cib_writes_enabled && cib_status == pcmk_ok && to_disk) {
crm_debug("Triggering CIB write for %s op", op);
mainloop_set_trigger(cib_writer);
}
return pcmk_ok;
}
crm_err("Ignoring invalid CIB");
if (the_cib) {
crm_warn("Reverting to last known CIB");
} else {
crm_crit("Could not write out new CIB and no saved version to revert to");
}
return -ENODATA;
}
static void
cib_diskwrite_complete(mainloop_child_t * p, pid_t pid, int core, int signo, int exitcode)
{
const char *errmsg = "Could not write CIB to disk";
if ((exitcode != 0) && cib_writes_enabled) {
cib_writes_enabled = FALSE;
errmsg = "Disabling CIB disk writes after failure";
}
if ((signo == 0) && (exitcode == 0)) {
crm_trace("Disk write [%d] succeeded", (int) pid);
} else if (signo == 0) {
crm_err("%s: process %d exited %d", errmsg, (int) pid, exitcode);
} else {
crm_err("%s: process %d terminated with signal %d (%s)%s",
errmsg, (int) pid, signo, strsignal(signo),
(core? " and dumped core" : ""));
}
mainloop_trigger_complete(cib_writer);
}
int
write_cib_contents(gpointer p)
{
int exit_rc = pcmk_ok;
xmlNode *cib_local = NULL;
/* Make a copy of the CIB to write (possibly in a forked child) */
if (p) {
/* Synchronous write out */
cib_local = pcmk__xml_copy(NULL, p);
} else {
int pid = 0;
int bb_state = qb_log_ctl(QB_LOG_BLACKBOX, QB_LOG_CONF_STATE_GET, 0);
/* Turn it off before the fork() to avoid:
* - 2 processes writing to the same shared mem
* - the child needing to disable it
* (which would close it from underneath the parent)
* This way, the shared mem files are already closed
*/
qb_log_ctl(QB_LOG_BLACKBOX, QB_LOG_CONF_ENABLED, QB_FALSE);
pid = fork();
if (pid < 0) {
crm_err("Disabling disk writes after fork failure: %s", pcmk_rc_str(errno));
cib_writes_enabled = FALSE;
return FALSE;
}
if (pid) {
/* Parent */
mainloop_child_add(pid, 0, "disk-writer", NULL, cib_diskwrite_complete);
if (bb_state == QB_LOG_STATE_ENABLED) {
/* Re-enable now that it it safe */
qb_log_ctl(QB_LOG_BLACKBOX, QB_LOG_CONF_ENABLED, QB_TRUE);
}
return -1; /* -1 means 'still work to do' */
}
/* Asynchronous write-out after a fork() */
/* In theory, we can scribble on the_cib here and not affect the parent,
* but let's be safe anyway.
*/
cib_local = pcmk__xml_copy(NULL, the_cib);
}
/* Write the CIB */
exit_rc = cib_file_write_with_digest(cib_local, cib_root, "cib.xml");
/* A nonzero exit code will cause further writes to be disabled */
pcmk__xml_free(cib_local);
if (p == NULL) {
crm_exit_t exit_code = CRM_EX_OK;
switch (exit_rc) {
case pcmk_ok:
exit_code = CRM_EX_OK;
break;
case pcmk_err_cib_modified:
exit_code = CRM_EX_DIGEST; // Existing CIB doesn't match digest
break;
case pcmk_err_cib_backup: // Existing CIB couldn't be backed up
case pcmk_err_cib_save: // New CIB couldn't be saved
exit_code = CRM_EX_CANTCREAT;
break;
default:
exit_code = CRM_EX_ERROR;
break;
}
/* Use _exit() because exit() could affect the parent adversely */
pcmk_common_cleanup();
_exit(exit_code);
}
return exit_rc;
}

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