static void
slave_dead(slave *s)
{
if (s->fd >= 0) {
close (s->fd);
s->fd = -1;
}
s->flags |= SLAVE_F_DEAD;
slave_seen(s);
}
static void
slave_dead(krb5_context context, slave *s)
{
krb5_warnx(context, "slave %s dead", s->name);
if (!rk_IS_BAD_SOCKET(s->fd)) {
rk_closesocket (s->fd);
s->fd = rk_INVALID_SOCKET;
}
s->flags |= SLAVE_F_DEAD;
slave_seen(s);
}
static int
process_msg (krb5_context context, slave *s, int log_fd,
const char *database, u_int32_t current_version)
{
int ret = 0;
krb5_data out;
krb5_storage *sp;
int32_t tmp;
ret = krb5_read_priv_message(context, s->ac, &s->fd, &out);
if(ret) {
krb5_warn (context, ret, "error reading message from %s", s->name);
return 1;
}
sp = krb5_storage_from_mem (out.data, out.length);
if (sp == NULL) {
krb5_warnx (context, "process_msg: no memory");
krb5_data_free (&out);
return 1;
}
if (krb5_ret_int32 (sp, &tmp) != 0) {
krb5_warnx (context, "process_msg: client send too short command");
krb5_data_free (&out);
return 1;
}
switch (tmp) {
case I_HAVE :
ret = krb5_ret_int32 (sp, &tmp);
if (ret != 0) {
krb5_warnx (context, "process_msg: client send too I_HAVE data");
break;
}
s->version = tmp;
ret = send_diffs (context, s, log_fd, database, current_version);
break;
case I_AM_HERE :
break;
case ARE_YOU_THERE:
case FOR_YOU :
default :
krb5_warnx (context, "Ignoring command %d", tmp);
break;
}
krb5_data_free (&out);
slave_seen(s);
return ret;
}
static int
send_diffs (krb5_context context, slave *s, int log_fd,
const char *database, u_int32_t current_version)
{
krb5_storage *sp;
u_int32_t ver;
time_t timestamp;
enum kadm_ops op;
u_int32_t len;
off_t right, left;
krb5_data data;
int ret = 0;
if (s->version == current_version)
return 0;
if (s->flags & SLAVE_F_DEAD)
return 0;
sp = kadm5_log_goto_end (log_fd);
right = krb5_storage_seek(sp, 0, SEEK_CUR);
for (;;) {
if (kadm5_log_previous (sp, &ver, ×tamp, &op, &len))
abort ();
left = krb5_storage_seek(sp, -16, SEEK_CUR);
if (ver == s->version)
return 0;
if (ver == s->version + 1)
break;
if (left == 0)
return send_complete (context, s, database, current_version);
}
ret = krb5_data_alloc (&data, right - left + 4);
if (ret) {
krb5_warn (context, ret, "send_diffs: krb5_data_alloc");
slave_dead(s);
return 1;
}
krb5_storage_read (sp, (char *)data.data + 4, data.length - 4);
krb5_storage_free(sp);
sp = krb5_storage_from_data (&data);
if (sp == NULL) {
krb5_warnx (context, "send_diffs: krb5_storage_from_data");
slave_dead(s);
return 1;
}
krb5_store_int32 (sp, FOR_YOU);
krb5_storage_free(sp);
ret = krb5_write_priv_message(context, s->ac, &s->fd, &data);
krb5_data_free(&data);
if (ret) {
krb5_warn (context, ret, "send_diffs: krb5_write_priv_message");
slave_dead(s);
return 1;
}
slave_seen(s);
return 0;
}
static int
send_complete (krb5_context context, slave *s,
const char *database, u_int32_t current_version)
{
krb5_error_code ret;
krb5_storage *sp;
HDB *db;
krb5_data data;
char buf[8];
ret = hdb_create (context, &db, database);
if (ret)
krb5_err (context, 1, ret, "hdb_create: %s", database);
ret = db->hdb_open (context, db, O_RDONLY, 0);
if (ret)
krb5_err (context, 1, ret, "db->open");
sp = krb5_storage_from_mem (buf, 4);
if (sp == NULL)
krb5_errx (context, 1, "krb5_storage_from_mem");
krb5_store_int32 (sp, TELL_YOU_EVERYTHING);
krb5_storage_free (sp);
data.data = buf;
data.length = 4;
ret = krb5_write_priv_message(context, s->ac, &s->fd, &data);
if (ret) {
krb5_warn (context, ret, "krb5_write_priv_message");
slave_dead(s);
return ret;
}
ret = hdb_foreach (context, db, 0, prop_one, s);
if (ret) {
krb5_warn (context, ret, "hdb_foreach");
slave_dead(s);
return ret;
}
(*db->hdb_close)(context, db);
(*db->hdb_destroy)(context, db);
sp = krb5_storage_from_mem (buf, 8);
if (sp == NULL)
krb5_errx (context, 1, "krb5_storage_from_mem");
krb5_store_int32 (sp, NOW_YOU_HAVE);
krb5_store_int32 (sp, current_version);
krb5_storage_free (sp);
data.length = 8;
s->version = current_version;
ret = krb5_write_priv_message(context, s->ac, &s->fd, &data);
if (ret) {
slave_dead(s);
krb5_warn (context, ret, "krb5_write_priv_message");
return ret;
}
slave_seen(s);
return 0;
}
static void
add_slave (krb5_context context, krb5_keytab keytab, slave **root, int fd)
{
krb5_principal server;
krb5_error_code ret;
slave *s;
socklen_t addr_len;
krb5_ticket *ticket = NULL;
char hostname[128];
s = malloc(sizeof(*s));
if (s == NULL) {
krb5_warnx (context, "add_slave: no memory");
return;
}
s->name = NULL;
s->ac = NULL;
addr_len = sizeof(s->addr);
s->fd = accept (fd, (struct sockaddr *)&s->addr, &addr_len);
if (s->fd < 0) {
krb5_warn (context, errno, "accept");
goto error;
}
gethostname(hostname, sizeof(hostname));
ret = krb5_sname_to_principal (context, hostname, IPROP_NAME,
KRB5_NT_SRV_HST, &server);
if (ret) {
krb5_warn (context, ret, "krb5_sname_to_principal");
goto error;
}
ret = krb5_recvauth (context, &s->ac, &s->fd,
IPROP_VERSION, server, 0, keytab, &ticket);
krb5_free_principal (context, server);
if (ret) {
krb5_warn (context, ret, "krb5_recvauth");
goto error;
}
ret = krb5_unparse_name (context, ticket->client, &s->name);
if (ret) {
krb5_warn (context, ret, "krb5_unparse_name");
goto error;
}
if (check_acl (context, s->name)) {
krb5_warnx (context, "%s not in acl", s->name);
goto error;
}
krb5_free_ticket (context, ticket);
ticket = NULL;
{
slave *l = *root;
while (l) {
if (strcmp(l->name, s->name) == 0)
break;
l = l->next;
}
if (l) {
if (l->flags & SLAVE_F_DEAD) {
remove_slave(context, l, root);
} else {
krb5_warnx (context, "second connection from %s", s->name);
goto error;
}
}
}
krb5_warnx (context, "connection from %s", s->name);
s->version = 0;
s->flags = 0;
slave_seen(s);
s->next = *root;
*root = s;
return;
error:
remove_slave(context, s, root);
}
static int
process_msg (kadm5_server_context *server_context, slave *s, int log_fd,
const char *database, uint32_t current_version,
uint32_t current_tstamp)
{
krb5_context context = server_context->context;
int ret = 0;
krb5_data out;
krb5_storage *sp;
uint32_t tmp;
ret = krb5_read_priv_message(context, s->ac, &s->fd, &out);
if(ret) {
krb5_warn(context, ret, "error reading message from %s", s->name);
return 1;
}
sp = krb5_storage_from_mem(out.data, out.length);
if (sp == NULL) {
krb5_warnx(context, "process_msg: no memory");
krb5_data_free(&out);
return 1;
}
if (krb5_ret_uint32(sp, &tmp) != 0) {
krb5_warnx(context, "process_msg: client send too short command");
krb5_data_free(&out);
return 1;
}
switch (tmp) {
case I_HAVE :
ret = krb5_ret_uint32(sp, &tmp);
if (ret != 0) {
krb5_warnx(context, "process_msg: client send too little I_HAVE data");
break;
}
/* new started slave that have old log */
if (s->version == 0 && tmp != 0) {
if (current_version < tmp) {
krb5_warnx(context, "Slave %s (version %u) have later version "
"the master (version %u) OUT OF SYNC",
s->name, tmp, current_version);
}
if (verbose)
krb5_warnx(context, "slave %s updated from %u to %u",
s->name, s->version, tmp);
s->version = tmp;
}
if (tmp < s->version) {
krb5_warnx(context, "Slave %s claims to not have "
"version we already sent to it", s->name);
s->version = tmp;
}
ret = send_diffs(server_context, s, log_fd, database, current_version,
current_tstamp);
break;
case I_AM_HERE :
if (verbose)
krb5_warnx(context, "slave %s is there", s->name);
break;
case ARE_YOU_THERE:
case FOR_YOU :
default :
krb5_warnx(context, "Ignoring command %d", tmp);
break;
}
krb5_data_free(&out);
krb5_storage_free(sp);
slave_seen(s);
return ret;
}
static int
send_diffs (kadm5_server_context *server_context, slave *s, int log_fd,
const char *database, uint32_t current_version,
uint32_t current_tstamp)
{
krb5_context context = server_context->context;
krb5_storage *sp;
uint32_t ver, initial_version, initial_version2;
uint32_t initial_tstamp, initial_tstamp2;
enum kadm_ops op;
uint32_t len;
off_t right, left;
krb5_ssize_t bytes;
krb5_data data;
int ret = 0;
if (s->flags & SLAVE_F_DEAD) {
krb5_warnx(context, "not sending diffs to dead slave %s", s->name);
return 0;
}
if (s->version == current_version) {
char buf[4];
sp = krb5_storage_from_mem(buf, 4);
if (sp == NULL)
krb5_errx(context, IPROPD_RESTART, "krb5_storage_from_mem");
ret = krb5_store_uint32(sp, YOU_HAVE_LAST_VERSION);
krb5_storage_free(sp);
data.data = buf;
data.length = 4;
if (ret == 0) {
ret = krb5_write_priv_message(context, s->ac, &s->fd, &data);
if (ret) {
krb5_warn(context, ret, "send_diffs: failed to send to slave");
slave_dead(context, s);
}
krb5_warnx(context, "slave %s in sync already at version %ld",
s->name, (long)s->version);
}
return ret;
}
if (verbose)
krb5_warnx(context, "sending diffs to live-seeming slave %s", s->name);
/*
* XXX The code that makes the diffs should be made a separate function,
* then error handling (send_are_you_there() or slave_dead()) can be done
* here.
*/
if (flock(log_fd, LOCK_SH) == -1) {
krb5_warn(context, errno, "could not obtain shared lock on log file");
send_are_you_there(context, s);
return errno;
}
ret = kadm5_log_get_version_fd(server_context, log_fd, LOG_VERSION_FIRST,
&initial_version, &initial_tstamp);
sp = kadm5_log_goto_end(server_context, log_fd);
flock(log_fd, LOCK_UN);
if (ret) {
if (sp != NULL)
krb5_storage_free(sp);
krb5_warn(context, ret, "send_diffs: failed to read log");
send_are_you_there(context, s);
return ret;
}
if (sp == NULL) {
send_are_you_there(context, s);
krb5_warn(context, errno ? errno : EINVAL,
"send_diffs: failed to read log");
return errno ? errno : EINVAL;
}
/*
* We're not holding any locks here, so we can't prevent truncations.
*
* We protect against this by re-checking that the initial version and
* timestamp are the same before and after this loop.
*/
right = krb5_storage_seek(sp, 0, SEEK_CUR);
if (right == (off_t)-1) {
krb5_storage_free(sp);
send_are_you_there(context, s);
return errno;
}
for (;;) {
ret = kadm5_log_previous (context, sp, &ver, NULL, &op, &len);
if (ret)
krb5_err(context, IPROPD_RESTART, ret,
"send_diffs: failed to find previous entry");
left = krb5_storage_seek(sp, -16, SEEK_CUR);
if (left == (off_t)-1) {
krb5_storage_free(sp);
send_are_you_there(context, s);
return errno;
}
if (ver == s->version + 1)
break;
/*
* We don't expect to reach the slave's version, except when it is
* starting empty with the uber record.
*/
if (ver == s->version && !(ver == 0 && op == kadm_nop)) {
/*
* This shouldn't happen, but recall we're not holding a lock on
* the log.
*/
krb5_storage_free(sp);
krb5_warnx(context, "iprop log truncated while sending diffs to "
"slave?? ver = %lu", (unsigned long)ver);
send_are_you_there(context, s);
return 0;
}
/* If we've reached the uber record, send the complete database */
if (left == 0 || (ver == 0 && op == kadm_nop)) {
krb5_storage_free(sp);
krb5_warnx(context,
"slave %s (version %lu) out of sync with master "
"(first version in log %lu), sending complete database",
s->name, (unsigned long)s->version, (unsigned long)ver);
return send_complete (context, s, database, current_version, ver,
initial_tstamp);
}
}
assert(ver == s->version + 1);
krb5_warnx(context,
"syncing slave %s from version %lu to version %lu",
s->name, (unsigned long)s->version,
(unsigned long)current_version);
ret = krb5_data_alloc (&data, right - left + 4);
if (ret) {
krb5_storage_free(sp);
krb5_warn (context, ret, "send_diffs: krb5_data_alloc");
send_are_you_there(context, s);
return 1;
}
bytes = krb5_storage_read(sp, (char *)data.data + 4, data.length - 4);
krb5_storage_free(sp);
if (bytes != data.length - 4) {
krb5_warnx(context, "iprop log truncated while sending diffs to "
"slave?? ver = %lu", (unsigned long)ver);
send_are_you_there(context, s);
return 1;
}
/*
* Check that we have the same log initial version and timestamp now as
* when we dropped the shared lock on the log file! Else we could be
* sending garbage to the slave.
*/
if (flock(log_fd, LOCK_SH) == -1) {
krb5_warn(context, errno, "could not obtain shared lock on log file");
send_are_you_there(context, s);
return 1;
}
ret = kadm5_log_get_version_fd(server_context, log_fd, LOG_VERSION_FIRST,
&initial_version2, &initial_tstamp2);
flock(log_fd, LOCK_UN);
if (ret) {
krb5_warn(context, ret,
"send_diffs: failed to read log while producing diffs");
send_are_you_there(context, s);
return 1;
}
if (initial_version != initial_version2 ||
initial_tstamp != initial_tstamp2) {
krb5_warn(context, ret,
"send_diffs: log truncated while producing diffs");
send_are_you_there(context, s);
return 1;
}
sp = krb5_storage_from_data (&data);
if (sp == NULL) {
krb5_warnx (context, "send_diffs: krb5_storage_from_data");
send_are_you_there(context, s);
return 1;
}
krb5_store_uint32 (sp, FOR_YOU);
krb5_storage_free(sp);
ret = krb5_write_priv_message(context, s->ac, &s->fd, &data);
krb5_data_free(&data);
if (ret) {
krb5_warn (context, ret, "send_diffs: krb5_write_priv_message");
slave_dead(context, s);
return 1;
}
slave_seen(s);
s->version = current_version;
krb5_warnx(context, "slave %s is now up to date (%u)", s->name, s->version);
return 0;
}
static int
send_complete (krb5_context context, slave *s, const char *database,
uint32_t current_version, uint32_t oldest_version,
uint32_t initial_log_tstamp)
{
krb5_error_code ret;
krb5_storage *dump = NULL;
uint32_t vno = 0;
krb5_data data;
int fd = -1;
struct stat st;
char *dfn;
ret = asprintf(&dfn, "%s/ipropd.dumpfile", hdb_db_dir(context));
if (ret == -1 || !dfn) {
krb5_warn(context, ENOMEM, "Cannot allocate memory");
return ENOMEM;
}
fd = open(dfn, O_CREAT|O_RDWR, 0600);
if (fd == -1) {
ret = errno;
krb5_warn(context, ret, "Cannot open/create iprop dumpfile %s", dfn);
free(dfn);
return ret;
}
free(dfn);
dump = krb5_storage_from_fd(fd);
if (!dump) {
ret = errno;
krb5_warn(context, ret, "krb5_storage_from_fd");
goto done;
}
for (;;) {
ret = flock(fd, LOCK_SH);
if (ret == -1) {
ret = errno;
krb5_warn(context, ret, "flock(fd, LOCK_SH)");
goto done;
}
if (krb5_storage_seek(dump, 0, SEEK_SET) == (off_t)-1) {
ret = errno;
krb5_warn(context, ret, "krb5_storage_seek(dump, 0, SEEK_SET)");
goto done;
}
vno = 0;
ret = krb5_ret_uint32(dump, &vno);
if (ret && ret != HEIM_ERR_EOF) {
krb5_warn(context, ret, "krb5_ret_uint32(dump, &vno)");
goto done;
}
if (fstat(fd, &st) == -1) {
ret = errno;
krb5_warn(context, ret, "send_complete: could not stat dump file");
goto done;
}
/*
* If the current dump has an appropriate version, then we can
* break out of the loop and send the file below.
*/
if (ret == 0 && vno != 0 && st.st_mtime > initial_log_tstamp &&
vno >= oldest_version && vno <= current_version)
break;
if (verbose)
krb5_warnx(context, "send_complete: dumping HDB");
/*
* Otherwise, we may need to write a new dump file. We
* obtain an exclusive lock on the fd. Because this is
* not guaranteed to be an upgrade of our existing shared
* lock, someone else may have written a new dumpfile while
* we were waiting and so we must first check the vno of
* the dump to see if that happened. If it did, we need
* to go back to the top of the loop so that we can downgrade
* our lock to a shared one.
*/
ret = flock(fd, LOCK_EX);
if (ret == -1) {
ret = errno;
krb5_warn(context, ret, "flock(fd, LOCK_EX)");
goto done;
}
ret = krb5_storage_seek(dump, 0, SEEK_SET);
if (ret == -1) {
ret = errno;
krb5_warn(context, ret, "krb5_storage_seek(dump, 0, SEEK_SET)");
goto done;
}
vno = 0;
ret = krb5_ret_uint32(dump, &vno);
if (ret && ret != HEIM_ERR_EOF) {
krb5_warn(context, ret, "krb5_ret_uint32(dump, &vno)");
goto done;
}
if (fstat(fd, &st) == -1) {
ret = errno;
krb5_warn(context, ret, "send_complete: could not stat dump file");
goto done;
}
/* check if someone wrote a better version for us */
if (ret == 0 && vno != 0 && st.st_mtime > initial_log_tstamp &&
vno >= oldest_version && vno <= current_version)
continue;
/* Now, we know that we must write a new dump file. */
ret = write_dump(context, dump, database, current_version);
if (ret)
goto done;
/*
* And we must continue to the top of the loop so that we can
* downgrade to a shared lock.
*/
}
/*
* Leaving the above loop, dump should have a ptr right after the initial
* 4 byte DB version number and we should have a shared lock on the file
* (which we may have just created), so we are reading to simply blast
* the data down the wire.
*/
for (;;) {
ret = krb5_ret_data(dump, &data);
if (ret == HEIM_ERR_EOF) {
ret = 0; /* EOF is not an error, it's success */
goto done;
}
if (ret) {
krb5_warn(context, ret, "krb5_ret_data(dump, &data)");
slave_dead(context, s);
goto done;
}
ret = krb5_write_priv_message(context, s->ac, &s->fd, &data);
krb5_data_free(&data);
if (ret) {
krb5_warn (context, ret, "krb5_write_priv_message");
slave_dead(context, s);
goto done;
}
}
done:
if (!ret) {
s->version = vno;
slave_seen(s);
}
if (fd != -1)
close(fd);
if (dump)
krb5_storage_free(dump);
return ret;
}
static int
send_diffs (krb5_context context, slave *s, int log_fd,
const char *database, uint32_t current_version)
{
krb5_storage *sp;
uint32_t ver;
time_t timestamp;
enum kadm_ops op;
uint32_t len;
off_t right, left;
krb5_data data;
int ret = 0;
if (s->version == current_version) {
krb5_warnx(context, "slave %s in sync already at version %ld",
s->name, (long)s->version);
return 0;
}
if (s->flags & SLAVE_F_DEAD)
return 0;
/* if slave is a fresh client, starting over */
if (s->version == 0) {
krb5_warnx(context, "sending complete log to fresh slave %s",
s->name);
return send_complete (context, s, database, current_version);
}
sp = kadm5_log_goto_end (log_fd);
right = krb5_storage_seek(sp, 0, SEEK_CUR);
for (;;) {
ret = kadm5_log_previous (context, sp, &ver, ×tamp, &op, &len);
if (ret)
krb5_err(context, 1, ret,
"send_diffs: failed to find previous entry");
left = krb5_storage_seek(sp, -16, SEEK_CUR);
if (ver == s->version)
return 0;
if (ver == s->version + 1)
break;
if (left == 0) {
krb5_storage_free(sp);
krb5_warnx(context,
"slave %s (version %lu) out of sync with master "
"(first version in log %lu), sending complete database",
s->name, (unsigned long)s->version, (unsigned long)ver);
return send_complete (context, s, database, current_version);
}
}
krb5_warnx(context,
"syncing slave %s from version %lu to version %lu",
s->name, (unsigned long)s->version,
(unsigned long)current_version);
ret = krb5_data_alloc (&data, right - left + 4);
if (ret) {
krb5_storage_free(sp);
krb5_warn (context, ret, "send_diffs: krb5_data_alloc");
slave_dead(context, s);
return 1;
}
krb5_storage_read (sp, (char *)data.data + 4, data.length - 4);
krb5_storage_free(sp);
sp = krb5_storage_from_data (&data);
if (sp == NULL) {
krb5_warnx (context, "send_diffs: krb5_storage_from_data");
slave_dead(context, s);
return 1;
}
krb5_store_int32 (sp, FOR_YOU);
krb5_storage_free(sp);
ret = krb5_write_priv_message(context, s->ac, &s->fd, &data);
krb5_data_free(&data);
if (ret) {
krb5_warn (context, ret, "send_diffs: krb5_write_priv_message");
slave_dead(context, s);
return 1;
}
slave_seen(s);
s->version = current_version;
return 0;
}
