utils.c

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/*
 * Copyright 2004-2022 the Pacemaker project contributors
 *
 * The version control history for this file may have further details.
 *
 * This source code is licensed under the GNU Lesser General Public License
 * version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
 */

#include <crm_internal.h>

#ifndef _GNU_SOURCE
#  define _GNU_SOURCE
#endif

#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/utsname.h>

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>
#include <pwd.h>
#include <time.h>
#include <libgen.h>
#include <signal.h>
#include <grp.h>

#include <qb/qbdefs.h>

#include <crm/crm.h>
#include <crm/services.h>
#include <crm/msg_xml.h>
#include <crm/cib/internal.h>
#include <crm/common/xml.h>
#include <crm/common/util.h>
#include <crm/common/ipc.h>
#include <crm/common/iso8601.h>
#include <crm/common/mainloop.h>
#include <libxml2/libxml/relaxng.h>

#include "crmcommon_private.h"

CRM_TRACE_INIT_DATA(common);

gboolean crm_config_error = FALSE;
gboolean crm_config_warning = FALSE;
char *crm_system_name = NULL;

bool
pcmk__is_user_in_group(const char *user, const char *group)
{
    struct group *grent;
    char **gr_mem;

    if (user == NULL || group == NULL) {
        return false;
    }
    
    setgrent();
    while ((grent = getgrent()) != NULL) {
        if (grent->gr_mem == NULL) {
            continue;
        }

        if(strcmp(group, grent->gr_name) != 0) {
            continue;
        }

        gr_mem = grent->gr_mem;
        while (*gr_mem != NULL) {
            if (!strcmp(user, *gr_mem++)) {
                endgrent();
                return true;
            }
        }
    }
    endgrent();
    return false;
}

int
crm_user_lookup(const char *name, uid_t * uid, gid_t * gid)
{
    int rc = pcmk_ok;
    char *buffer = NULL;
    struct passwd pwd;
    struct passwd *pwentry = NULL;

    buffer = calloc(1, PCMK__PW_BUFFER_LEN);
    if (buffer == NULL) {
        return -ENOMEM;
    }

    rc = getpwnam_r(name, &pwd, buffer, PCMK__PW_BUFFER_LEN, &pwentry);
    if (pwentry) {
        if (uid) {
            *uid = pwentry->pw_uid;
        }
        if (gid) {
            *gid = pwentry->pw_gid;
        }
        crm_trace("User %s has uid=%d gid=%d", name, pwentry->pw_uid, pwentry->pw_gid);

    } else {
        rc = rc? -rc : -EINVAL;
        crm_info("User %s lookup: %s", name, pcmk_strerror(rc));
    }

    free(buffer);
    return rc;
}

int
pcmk_daemon_user(uid_t *uid, gid_t *gid)
{
    static uid_t daemon_uid;
    static gid_t daemon_gid;
    static bool found = false;
    int rc = pcmk_ok;

    if (!found) {
        rc = crm_user_lookup(CRM_DAEMON_USER, &daemon_uid, &daemon_gid);
        if (rc == pcmk_ok) {
            found = true;
        }
    }
    if (found) {
        if (uid) {
            *uid = daemon_uid;
        }
        if (gid) {
            *gid = daemon_gid;
        }
    }
    return rc;
}

static int
version_helper(const char *text, const char **end_text)
{
    int atoi_result = -1;

    CRM_ASSERT(end_text != NULL);

    errno = 0;

    if (text != NULL && text[0] != 0) {
        /* seemingly sacrificing const-correctness -- because while strtol
           doesn't modify the input, it doesn't want to artificially taint the
           "end_text" pointer-to-pointer-to-first-char-in-string with constness
           in case the input wasn't actually constant -- by semantic definition
           not a single character will get modified so it shall be perfectly
           safe to make compiler happy with dropping "const" qualifier here */
        atoi_result = (int) strtol(text, (char **) end_text, 10);

        if (errno == EINVAL) {
            crm_err("Conversion of '%s' %c failed", text, text[0]);
            atoi_result = -1;
        }
    }
    return atoi_result;
}

/*
 * version1 < version2 : -1
 * version1 = version2 :  0
 * version1 > version2 :  1
 */
int
compare_version(const char *version1, const char *version2)
{
    int rc = 0;
    int lpc = 0;
    const char *ver1_iter, *ver2_iter;

    if (version1 == NULL && version2 == NULL) {
        return 0;
    } else if (version1 == NULL) {
        return -1;
    } else if (version2 == NULL) {
        return 1;
    }

    ver1_iter = version1;
    ver2_iter = version2;

    while (1) {
        int digit1 = 0;
        int digit2 = 0;

        lpc++;

        if (ver1_iter == ver2_iter) {
            break;
        }

        if (ver1_iter != NULL) {
            digit1 = version_helper(ver1_iter, &ver1_iter);
        }

        if (ver2_iter != NULL) {
            digit2 = version_helper(ver2_iter, &ver2_iter);
        }

        if (digit1 < digit2) {
            rc = -1;
            break;

        } else if (digit1 > digit2) {
            rc = 1;
            break;
        }

        if (ver1_iter != NULL && *ver1_iter == '.') {
            ver1_iter++;
        }
        if (ver1_iter != NULL && *ver1_iter == '\0') {
            ver1_iter = NULL;
        }

        if (ver2_iter != NULL && *ver2_iter == '.') {
            ver2_iter++;
        }
        if (ver2_iter != NULL && *ver2_iter == 0) {
            ver2_iter = NULL;
        }
    }

    if (rc == 0) {
        crm_trace("%s == %s (%d)", version1, version2, lpc);
    } else if (rc < 0) {
        crm_trace("%s < %s (%d)", version1, version2, lpc);
    } else if (rc > 0) {
        crm_trace("%s > %s (%d)", version1, version2, lpc);
    }

    return rc;
}

guint
crm_parse_interval_spec(const char *input)
{
    long long msec = -1;

    errno = 0;
    if (input == NULL) {
        return 0;

    } else if (input[0] == 'P') {
        crm_time_t *period_s = crm_time_parse_duration(input);

        if (period_s) {
            msec = 1000 * crm_time_get_seconds(period_s);
            crm_time_free(period_s);
        }

    } else {
        msec = crm_get_msec(input);
    }

    if (msec < 0) {
        crm_warn("Using 0 instead of '%s'", input);
        errno = EINVAL;
        return 0;
    }
    return (msec >= G_MAXUINT)? G_MAXUINT : (guint) msec;
}

static void
log_assertion_as(const char *file, const char *function, int line,
                 const char *assert_condition)
{
    if (!pcmk__is_daemon) {
        crm_enable_stderr(TRUE); // Make sure command-line user sees message
    }
    crm_err("%s: Triggered fatal assertion at %s:%d : %s",
            function, file, line, assert_condition);
}

/* coverity[+kill] */
static _Noreturn void
abort_as(const char *file, const char *function, int line,
         const char *assert_condition)
{
    log_assertion_as(file, function, line, assert_condition);
    abort();
}

/* coverity[+kill] */
static void
fail_assert_as(const char *file, const char *function, int line,
               const char *assert_condition)
{
    int status = 0;
    pid_t pid = 0;

    if (!pcmk__is_daemon) {
        abort_as(file, function, line, assert_condition); // does not return
    }

    pid = fork();
    switch (pid) {
        case -1: // Fork failed
            crm_warn("%s: Cannot dump core for non-fatal assertion at %s:%d "
                     ": %s", function, file, line, assert_condition);
            break;

        case 0: // Child process: just abort to dump core
            abort();
            break;

        default: // Parent process: wait for child
            crm_err("%s: Forked child [%d] to record non-fatal assertion at "
                    "%s:%d : %s", function, pid, file, line, assert_condition);
            crm_write_blackbox(SIGTRAP, NULL);
            do {
                if (waitpid(pid, &status, 0) == pid) {
                    return; // Child finished dumping core
                }
            } while (errno == EINTR);
            if (errno == ECHILD) {
                // crm_mon ignores SIGCHLD
                crm_trace("Cannot wait on forked child [%d] "
                          "(SIGCHLD is probably ignored)", pid);
            } else {
                crm_err("Cannot wait on forked child [%d]: %s",
                        pid, pcmk_rc_str(errno));
            }
            break;
    }
}

/* coverity[+kill] */
void
crm_abort(const char *file, const char *function, int line,
          const char *assert_condition, gboolean do_core, gboolean do_fork)
{
    if (!do_fork) {
        abort_as(file, function, line, assert_condition);
    } else if (do_core) {
        fail_assert_as(file, function, line, assert_condition);
    } else {
        log_assertion_as(file, function, line, assert_condition);
    }
}

void
pcmk__daemonize(const char *name, const char *pidfile)
{
    int rc;
    pid_t pid;

    /* Check before we even try... */
    rc = pcmk__pidfile_matches(pidfile, 1, name, &pid);
    if ((rc != pcmk_rc_ok) && (rc != ENOENT)) {
        crm_err("%s: already running [pid %lld in %s]",
                name, (long long) pid, pidfile);
        printf("%s: already running [pid %lld in %s]\n",
               name, (long long) pid, pidfile);
        crm_exit(CRM_EX_ERROR);
    }

    pid = fork();
    if (pid < 0) {
        fprintf(stderr, "%s: could not start daemon\n", name);
        crm_perror(LOG_ERR, "fork");
        crm_exit(CRM_EX_OSERR);

    } else if (pid > 0) {
        crm_exit(CRM_EX_OK);
    }

    rc = pcmk__lock_pidfile(pidfile, name);
    if (rc != pcmk_rc_ok) {
        crm_err("Could not lock '%s' for %s: %s " CRM_XS " rc=%d",
                pidfile, name, pcmk_rc_str(rc), rc);
        printf("Could not lock '%s' for %s: %s (%d)\n",
               pidfile, name, pcmk_rc_str(rc), rc);
        crm_exit(CRM_EX_ERROR);
    }

    umask(S_IWGRP | S_IWOTH | S_IROTH);

    close(STDIN_FILENO);
    pcmk__open_devnull(O_RDONLY);   // stdin (fd 0)

    close(STDOUT_FILENO);
    pcmk__open_devnull(O_WRONLY);   // stdout (fd 1)

    close(STDERR_FILENO);
    pcmk__open_devnull(O_WRONLY);   // stderr (fd 2)
}

char *
crm_meta_name(const char *field)
{
    int lpc = 0;
    int max = 0;
    char *crm_name = NULL;

    CRM_CHECK(field != NULL, return NULL);
    crm_name = crm_strdup_printf(CRM_META "_%s", field);

    /* Massage the names so they can be used as shell variables */
    max = strlen(crm_name);
    for (; lpc < max; lpc++) {
        switch (crm_name[lpc]) {
            case '-':
                crm_name[lpc] = '_';
                break;
        }
    }
    return crm_name;
}

const char *
crm_meta_value(GHashTable * hash, const char *field)
{
    char *key = NULL;
    const char *value = NULL;

    key = crm_meta_name(field);
    if (key) {
        value = g_hash_table_lookup(hash, key);
        free(key);
    }

    return value;
}

#ifdef HAVE_UUID_UUID_H
#  include <uuid/uuid.h>
#endif

char *
crm_generate_uuid(void)
{
    unsigned char uuid[16];
    char *buffer = malloc(37);  /* Including NUL byte */

    CRM_ASSERT(buffer != NULL);
    uuid_generate(uuid);
    uuid_unparse(uuid, buffer);
    return buffer;
}

#ifdef HAVE_GNUTLS_GNUTLS_H
void
crm_gnutls_global_init(void)
{
    signal(SIGPIPE, SIG_IGN);
    gnutls_global_init();
}
#endif

char *
pcmk_hostname(void)
{
    struct utsname hostinfo;

    return (uname(&hostinfo) < 0)? NULL : strdup(hostinfo.nodename);
}

bool
pcmk_str_is_infinity(const char *s) {
    return pcmk__str_any_of(s, CRM_INFINITY_S, CRM_PLUS_INFINITY_S, NULL);
}

bool
pcmk_str_is_minus_infinity(const char *s) {
    return pcmk__str_eq(s, CRM_MINUS_INFINITY_S, pcmk__str_none);
}

void
pcmk__sleep_ms(unsigned int ms)
{
    // @TODO Impose a sane maximum sleep to avoid hanging a process for long
    //CRM_CHECK(ms <= MAX_SLEEP, ms = MAX_SLEEP);

    // Use sleep() for any whole seconds
    if (ms >= 1000) {
        sleep(ms / 1000);
        ms -= ms / 1000;
    }

    if (ms == 0) {
        return;
    }

#if defined(HAVE_NANOSLEEP)
    // nanosleep() is POSIX-2008, so prefer that
    {
        struct timespec req = { .tv_sec = 0, .tv_nsec = (long) (ms * 1000000) };

        nanosleep(&req, NULL);
    }
#elif defined(HAVE_USLEEP)
    // usleep() is widely available, though considered obsolete
    usleep((useconds_t) ms);
#else
    // Otherwise use a trick with select() timeout
    {
        struct timeval tv = { .tv_sec = 0, .tv_usec = (suseconds_t) ms };

        select(0, NULL, NULL, NULL, &tv);
    }
#endif
}