diff options
Diffstat (limited to 'third_party/heimdal/lib/kadm5/ipropd_master.c')
| -rw-r--r-- | third_party/heimdal/lib/kadm5/ipropd_master.c | 1868 |
1 files changed, 1868 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/kadm5/ipropd_master.c b/third_party/heimdal/lib/kadm5/ipropd_master.c new file mode 100644 index 00000000000..a27d8f75a38 --- /dev/null +++ b/third_party/heimdal/lib/kadm5/ipropd_master.c @@ -0,0 +1,1868 @@ +/* + * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "iprop.h" +#include <rtbl.h> + +static krb5_log_facility *log_facility; + +static int verbose; + +static const char *slave_stats_file; +static const char *slave_stats_temp_file; +static const char *slave_time_missing = "2 min"; +static const char *slave_time_gone = "5 min"; + +static int time_before_missing; +static int time_before_gone; + +const char *master_hostname; +const char *pidfile_basename; + +static krb5_socket_t +make_signal_socket (krb5_context context) +{ +#ifndef NO_UNIX_SOCKETS + struct sockaddr_un addr; + const char *fn; + krb5_socket_t fd; + + fn = kadm5_log_signal_socket(context); + + fd = socket (AF_UNIX, SOCK_DGRAM, 0); + if (fd < 0) + krb5_err (context, 1, errno, "socket AF_UNIX"); + memset (&addr, 0, sizeof(addr)); + addr.sun_family = AF_UNIX; + strlcpy (addr.sun_path, fn, sizeof(addr.sun_path)); + unlink (addr.sun_path); + if (bind (fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) + krb5_err (context, 1, errno, "bind %s", addr.sun_path); + return fd; +#else + struct addrinfo *ai = NULL; + krb5_socket_t fd; + + kadm5_log_signal_socket_info(context, 1, &ai); + + fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); + if (rk_IS_BAD_SOCKET(fd)) + krb5_err (context, 1, rk_SOCK_ERRNO, "socket AF=%d", ai->ai_family); + + if (rk_IS_SOCKET_ERROR( bind (fd, ai->ai_addr, ai->ai_addrlen) )) + krb5_err (context, 1, rk_SOCK_ERRNO, "bind"); + return fd; +#endif +} + +static krb5_socket_t +make_listen_socket (krb5_context context, const char *port_str) +{ + krb5_socket_t fd; + int one = 1; + struct sockaddr_in addr; + + fd = socket (AF_INET, SOCK_STREAM, 0); + if (rk_IS_BAD_SOCKET(fd)) + krb5_err (context, 1, rk_SOCK_ERRNO, "socket AF_INET"); + setsockopt (fd, SOL_SOCKET, SO_REUSEADDR, (void *)&one, sizeof(one)); + memset (&addr, 0, sizeof(addr)); + addr.sin_family = AF_INET; + + if (port_str) { + addr.sin_port = krb5_getportbyname (context, + port_str, "tcp", + 0); + if (addr.sin_port == 0) { + char *ptr; + long port; + + port = strtol (port_str, &ptr, 10); + if (port == 0 && ptr == port_str) + krb5_errx (context, 1, "bad port `%s'", port_str); + addr.sin_port = htons(port); + } + } else { + addr.sin_port = krb5_getportbyname (context, IPROP_SERVICE, + "tcp", IPROP_PORT); + } + if(bind(fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) + krb5_err (context, 1, errno, "bind"); + if (listen(fd, SOMAXCONN) < 0) + krb5_err (context, 1, errno, "listen"); + return fd; +} + + +struct slave { + krb5_socket_t fd; + struct sockaddr_in addr; + char *name; + krb5_auth_context ac; + uint32_t version; + uint32_t version_tstamp; + uint32_t version_ack; + time_t seen; + unsigned long flags; +#define SLAVE_F_DEAD 0x1 +#define SLAVE_F_AYT 0x2 +#define SLAVE_F_READY 0x4 + /* + * We'll use non-blocking I/O so no slave can hold us back. + * + * We call the state left over from a partial write a "tail". + * + * The krb5_data holding an KRB-PRIV will be the write buffer. + */ + struct { + /* Every message we send is a KRB-PRIV with a 4-byte length prefixed */ + uint8_t header_buf[4]; + krb5_data header; + krb5_data packet; + size_t packet_off; + /* For send_complete() we need an sp as part of the tail */ + krb5_storage *dump; + uint32_t vno; + } tail; + struct { + uint8_t header_buf[4]; + krb5_data packet; + size_t offset; + int hlen; + } input; + /* + * Continuation for fair diff sending we send N entries at a time. + */ + struct { + off_t off_next_version; /* offset in log of next diff */ + uint32_t initial_version; /* at time of previous diff */ + uint32_t initial_tstamp; /* at time of previous diff */ + uint32_t last_version_sent; + int more; /* need to send more diffs */ + } next_diff; + struct slave *next; +}; + +typedef struct slave slave; + +static int +check_acl (krb5_context context, const char *name) +{ + const char *fn; + FILE *fp; + char buf[256]; + int ret = 1; + char *slavefile = NULL; + + if (asprintf(&slavefile, "%s/slaves", hdb_db_dir(context)) == -1 + || slavefile == NULL) + errx(1, "out of memory"); + + fn = krb5_config_get_string_default(context, + NULL, + slavefile, + "kdc", + "iprop-acl", + NULL); + + fp = fopen (fn, "r"); + free(slavefile); + if (fp == NULL) + return 1; + while (fgets(buf, sizeof(buf), fp) != NULL) { + buf[strcspn(buf, "\r\n")] = '\0'; + if (strcmp (buf, name) == 0) { + ret = 0; + break; + } + } + fclose (fp); + return ret; +} + +static void +slave_seen(slave *s) +{ + s->flags &= ~SLAVE_F_AYT; + s->seen = time(NULL); +} + +static int +slave_missing_p (slave *s) +{ + if (time(NULL) > s->seen + time_before_missing) + return 1; + return 0; +} + +static int +slave_gone_p (slave *s) +{ + if (time(NULL) > s->seen + time_before_gone) + return 1; + return 0; +} + +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 void +remove_slave (krb5_context context, slave *s, slave **root) +{ + slave **p; + + if (!rk_IS_BAD_SOCKET(s->fd)) + rk_closesocket (s->fd); + if (s->name) + free (s->name); + if (s->ac) + krb5_auth_con_free (context, s->ac); + + /* Free any pending input/output state */ + krb5_data_free(&s->input.packet); + krb5_data_free(&s->tail.packet); + krb5_storage_free(s->tail.dump); + + for (p = root; *p; p = &(*p)->next) + if (*p == s) { + *p = s->next; + break; + } + free (s); +} + +static void +add_slave (krb5_context context, krb5_keytab keytab, slave **root, + krb5_socket_t fd) +{ + krb5_principal server; + krb5_error_code ret; + slave *s; + socklen_t addr_len; + krb5_ticket *ticket = NULL; + char hostname[128]; + + s = calloc(1, sizeof(*s)); + if (s == NULL) { + krb5_warnx (context, "add_slave: no memory"); + return; + } + s->name = NULL; + s->ac = NULL; + s->input.packet.data = NULL; + s->tail.header.data = NULL; + s->tail.packet.data = NULL; + s->tail.dump = NULL; + + addr_len = sizeof(s->addr); + s->fd = accept (fd, (struct sockaddr *)&s->addr, &addr_len); + if (rk_IS_BAD_SOCKET(s->fd)) { + krb5_warn (context, rk_SOCK_ERRNO, "accept"); + goto error; + } + + if (master_hostname) + strlcpy(hostname, master_hostname, sizeof(hostname)); + else + 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); + + /* + * We'll be doing non-blocking I/O only after authentication. We don't + * want to get stuck talking to any one slave. + * + * If we get a partial write, we'll finish writing when the socket becomes + * writable. + * + * Partial reads will be treated as EOF, causing the slave to be marked + * dead. + * + * To do non-blocking I/O for authentication we'll have to implement our + * own krb5_recvauth(). + */ + socket_set_nonblocking(s->fd, 1); + + /* + * We write message lengths separately from the payload, and may do + * back-to-back small writes when flushing pending input and then a new + * update. Avoid Nagle delays. + */ +#if defined(IPPROTO_TCP) && defined(TCP_NODELAY) + { + int nodelay = 1; + (void) setsockopt(s->fd, IPPROTO_TCP, TCP_NODELAY, + (void *)&nodelay, sizeof(nodelay)); + } +#endif + + krb5_free_principal (context, server); + if (ret) { + krb5_warn (context, ret, "krb5_recvauth"); + goto error; + } + ret = krb5_unparse_name (context, ticket->client, &s->name); + krb5_free_ticket (context, ticket); + 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; + } + + { + 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->version_ack = 0; + s->flags = 0; + slave_seen(s); + s->next = *root; + *root = s; + return; +error: + remove_slave(context, s, root); +} + +static int +dump_one (krb5_context context, HDB *db, hdb_entry_ex *entry, void *v) +{ + krb5_error_code ret; + krb5_storage *dump = (krb5_storage *)v; + krb5_storage *sp; + krb5_data data; + + ret = hdb_entry2value (context, &entry->entry, &data); + if (ret) + return ret; + ret = krb5_data_realloc (&data, data.length + 4); + if (ret) + goto done; + memmove ((char *)data.data + 4, data.data, data.length - 4); + sp = krb5_storage_from_data(&data); + if (sp == NULL) { + ret = krb5_enomem(context); + goto done; + } + ret = krb5_store_uint32(sp, ONE_PRINC); + krb5_storage_free(sp); + + if (ret == 0) + ret = krb5_store_data(dump, data); + +done: + krb5_data_free (&data); + return ret; +} + +static int +write_dump (krb5_context context, krb5_storage *dump, + const char *database, uint32_t current_version) +{ + krb5_error_code ret; + krb5_storage *sp; + HDB *db; + krb5_data data; + char buf[8]; + + /* we assume that the caller has obtained an exclusive lock */ + + ret = krb5_storage_truncate(dump, 0); + if (ret) + return ret; + + if (krb5_storage_seek(dump, 0, SEEK_SET) != 0) + return errno; + + /* + * First we store zero as the HDB version, this will indicate to a + * later reader that the dumpfile is invalid. We later write the + * correct version in the file after we have written all of the + * messages. A dump with a zero version will not be considered + * to be valid. + */ + + ret = krb5_store_uint32(dump, 0); + + ret = hdb_create (context, &db, database); + if (ret) + krb5_err (context, IPROPD_RESTART, ret, "hdb_create: %s", database); + ret = db->hdb_open (context, db, O_RDONLY, 0); + if (ret) + krb5_err (context, IPROPD_RESTART, ret, "db->open"); + + sp = krb5_storage_from_mem (buf, 4); + if (sp == NULL) + krb5_errx (context, IPROPD_RESTART, "krb5_storage_from_mem"); + krb5_store_uint32 (sp, TELL_YOU_EVERYTHING); + krb5_storage_free (sp); + + data.data = buf; + data.length = 4; + + ret = krb5_store_data(dump, data); + if (ret) { + krb5_warn (context, ret, "write_dump"); + return ret; + } + + ret = hdb_foreach (context, db, HDB_F_ADMIN_DATA, dump_one, dump); + if (ret) { + krb5_warn (context, ret, "write_dump: hdb_foreach"); + 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, IPROPD_RESTART, "krb5_storage_from_mem"); + ret = krb5_store_uint32(sp, NOW_YOU_HAVE); + if (ret == 0) + krb5_store_uint32(sp, current_version); + krb5_storage_free (sp); + + data.length = 8; + + if (ret == 0) + ret = krb5_store_data(dump, data); + + /* + * We must ensure that the entire valid dump is written to disk + * before we write the current version at the front thus making + * it a valid dump file. If we crash around here, this can be + * important upon reboot. + */ + + if (ret == 0) + ret = krb5_storage_fsync(dump); + + if (ret == 0 && krb5_storage_seek(dump, 0, SEEK_SET) == -1) + ret = errno; + + /* Write current version at the front making the dump valid */ + + if (ret == 0) + ret = krb5_store_uint32(dump, current_version); + + /* + * We don't need to fsync(2) after the real version is written as + * it is not a disaster if it doesn't make it to disk if we crash. + * After all, we'll just create a new dumpfile. + */ + + if (ret == 0) + krb5_warnx(context, "wrote new dumpfile (version %u)", + current_version); + else + krb5_warn(context, ret, "failed to write new dumpfile (version %u)", + current_version); + + return ret; +} + +static int +mk_priv_tail(krb5_context context, slave *s, krb5_data *data) +{ + uint32_t len; + int ret; + + ret = krb5_mk_priv(context, s->ac, data, &s->tail.packet, NULL); + if (ret) + return ret; + + len = s->tail.packet.length; + _krb5_put_int(s->tail.header_buf, len, sizeof(s->tail.header_buf)); + s->tail.header.length = sizeof(s->tail.header_buf); + s->tail.header.data = s->tail.header_buf; + return 0; +} + +static int +have_tail(slave *s) +{ + return s->tail.header.length || s->tail.packet.length || s->tail.dump; +} + +static int +more_diffs(slave *s) +{ + return s->next_diff.more; +} + +#define SEND_COMPLETE_MAX_RECORDS 50 +#define SEND_DIFFS_MAX_RECORDS 50 + +static int +send_tail(krb5_context context, slave *s) +{ + krb5_data data; + ssize_t bytes = 0; + size_t rem = 0; + size_t n; + int ret; + + if (! have_tail(s)) + return 0; + + /* + * For the case where we're continuing a send_complete() send up to + * SEND_COMPLETE_MAX_RECORDS records now, and the rest asynchronously + * later. This ensures that sending a complete dump to a slow-to-drain + * client does not prevent others from getting serviced. + */ + for (n = 0; n < SEND_COMPLETE_MAX_RECORDS; n++) { + if (! have_tail(s)) + return 0; + + if (s->tail.header.length) { + bytes = krb5_net_write(context, &s->fd, + s->tail.header.data, + s->tail.header.length); + if (bytes < 0) + goto err; + + s->tail.header.length -= bytes; + s->tail.header.data = (char *)s->tail.header.data + bytes; + rem = s->tail.header.length; + if (rem) + goto ewouldblock; + } + + if (s->tail.packet.length) { + bytes = krb5_net_write(context, &s->fd, + (char *)s->tail.packet.data + s->tail.packet_off, + s->tail.packet.length - s->tail.packet_off); + if (bytes < 0) + goto err; + s->tail.packet_off += bytes; + if (bytes) + slave_seen(s); + rem = s->tail.packet.length - s->tail.packet_off; + if (rem) + goto ewouldblock; + + krb5_data_free(&s->tail.packet); + s->tail.packet_off = 0; + } + + if (s->tail.dump == NULL) + return 0; + + /* + * We're in the middle of a send_complete() that was interrupted by + * EWOULDBLOCK. Continue the sending of the dump. + */ + ret = krb5_ret_data(s->tail.dump, &data); + if (ret == HEIM_ERR_EOF) { + krb5_storage_free(s->tail.dump); + s->tail.dump = NULL; + s->version = s->tail.vno; + return 0; + } + + if (ret) { + krb5_warn(context, ret, "failed to read entry from dump!"); + } else { + ret = mk_priv_tail(context, s, &data); + krb5_data_free(&data); + if (ret == 0) + continue; + krb5_warn(context, ret, "failed to make and send a KRB-PRIV to %s", + s->name); + } + + slave_dead(context, s); + return ret; + } + + if (ret == 0 && s->tail.dump != NULL) + return EWOULDBLOCK; + +err: + if (errno != EAGAIN && errno != EWOULDBLOCK) { + krb5_warn(context, ret = errno, + "error sending diffs to now-dead slave %s", s->name); + slave_dead(context, s); + return ret; + } + +ewouldblock: + if (verbose) + krb5_warnx(context, "would block writing %llu bytes to slave %s", + (unsigned long long)rem, s->name); + return EWOULDBLOCK; +} + +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; + int fd = -1; + struct stat st; + char *dfn; + + ret = asprintf(&dfn, "%s/ipropd.dumpfile", hdb_db_dir(context)); + if (ret == -1 || !dfn) + return krb5_enomem(context); + + 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 start sending + * the data down the wire. + * + * Note: (krb5_storage_from_fd() dup()'s the fd) + */ + + s->tail.dump = dump; + s->tail.vno = vno; + dump = NULL; + ret = send_tail(context, s); + +done: + if (fd != -1) + close(fd); + if (dump) + krb5_storage_free(dump); + return ret; +} + +static int +send_are_you_there (krb5_context context, slave *s) +{ + krb5_storage *sp; + krb5_data data; + char buf[4]; + int ret; + + if (s->flags & (SLAVE_F_DEAD|SLAVE_F_AYT)) + return 0; + + /* + * Write any remainder of previous write, if we can. If we'd block we'll + * return EWOULDBLOCK. + */ + ret = send_tail(context, s); + if (ret) + return ret; + + krb5_warnx(context, "slave %s missing, sending AYT", s->name); + + s->flags |= SLAVE_F_AYT; + + data.data = buf; + data.length = 4; + + sp = krb5_storage_from_mem (buf, 4); + if (sp == NULL) { + krb5_warnx (context, "are_you_there: krb5_data_alloc"); + slave_dead(context, s); + return ENOMEM; + } + ret = krb5_store_uint32(sp, ARE_YOU_THERE); + krb5_storage_free (sp); + + if (ret == 0) + ret = mk_priv_tail(context, s, &data); + if (ret == 0) + ret = send_tail(context, s); + if (ret && ret != EWOULDBLOCK) { + krb5_warn(context, ret, "are_you_there"); + slave_dead(context, s); + } + return ret; +} + +static int +diffready(krb5_context context, slave *s) +{ + /* + * Don't send any diffs until slave has sent an I_HAVE telling us the + * initial version number! + */ + if ((s->flags & SLAVE_F_READY) == 0) + return 0; + + if (s->flags & SLAVE_F_DEAD) { + if (verbose) + krb5_warnx(context, "not sending diffs to dead slave %s", s->name); + return 0; + } + + /* Write any remainder of previous write, if we can. */ + if (send_tail(context, s) != 0) + return 0; + + return 1; +} + +static int +nodiffs(krb5_context context, slave *s, uint32_t current_version) +{ + krb5_storage *sp; + krb5_data data; + int ret; + + if (s->version < current_version) + return 0; + + /* + * If we had sent a partial diff, and now they're caught up, then there's + * no more. + */ + s->next_diff.more = 0; + + if (verbose) + krb5_warnx(context, "slave %s version %ld already sent", s->name, + (long)s->version); + sp = krb5_storage_emem(); + if (sp == NULL) + krb5_errx(context, IPROPD_RESTART, "krb5_storage_from_mem"); + + ret = krb5_store_uint32(sp, YOU_HAVE_LAST_VERSION); + if (ret == 0) { + krb5_data_zero(&data); + ret = krb5_storage_to_data(sp, &data); + } + krb5_storage_free(sp); + if (ret == 0) { + ret = mk_priv_tail(context, s, &data); + krb5_data_free(&data); + } + if (ret == 0) + send_tail(context, s); + + return 1; +} + +/* + * Lock the log and return initial version and timestamp + */ +static int +get_first(kadm5_server_context *server_context, int log_fd, + uint32_t *initial_verp, uint32_t *initial_timep) +{ + krb5_context context = server_context->context; + int ret; + + /* + * We don't want to perform tight retry loops on log access errors, so on + * error mark the slave dead. The slave reconnect after a delay... + */ + if (flock(log_fd, LOCK_SH) == -1) { + krb5_warn(context, errno, "could not obtain shared lock on log file"); + return -1; + } + + ret = kadm5_log_get_version_fd(server_context, log_fd, LOG_VERSION_FIRST, + initial_verp, initial_timep); + if (ret == HEIM_ERR_EOF) + ret = kadm5_log_get_version_fd(server_context, log_fd, + LOG_VERSION_UBER, initial_verp, + initial_timep); + if (ret != 0) { + flock(log_fd, LOCK_UN); + krb5_warn(context, ret, "could not read initial log entry"); + return -1; + } + + return 0; +} + +/*- + * Find the left end of the diffs in the log we want to send. + * + * - On success, return a positive offset to the first new entry, retaining + * a read lock on the log file. + * - On error, return a negative offset, with the lock released. + * - If we simply find no successor entry in the log, return zero + * with the lock released, which indicates that fallback to send_complete() + * is needed. + */ +static off_t +get_left(kadm5_server_context *server_context, slave *s, krb5_storage *sp, + int log_fd, uint32_t current_version, + uint32_t *initial_verp, uint32_t *initial_timep) +{ + krb5_context context = server_context->context; + off_t pos; + off_t left; + int ret; + + for (;;) { + uint32_t ver = s->version; + + /* This acquires a read lock on success */ + ret = get_first(server_context, log_fd, + initial_verp, initial_timep); + if (ret != 0) + return -1; + + /* When the slave version is out of range, send the whole database. */ + if (ver == 0 || ver < *initial_verp || ver > current_version) { + flock(log_fd, LOCK_UN); + return 0; + } + + /* Avoid seeking past the last committed record */ + if (kadm5_log_goto_end(server_context, sp) != 0 || + (pos = krb5_storage_seek(sp, 0, SEEK_CUR)) < 0) + goto err; + + /* + * First try to see if we can find it quickly by seeking to the right + * end of the previous diff sent. + */ + if (s->next_diff.last_version_sent > 0 && + s->next_diff.off_next_version > 0 && + s->next_diff.off_next_version < pos && + s->next_diff.initial_version == *initial_verp && + s->next_diff.initial_tstamp == *initial_timep) { + /* + * Sanity check that the left version matches what we wanted, the + * log may have been truncated since. + */ + left = s->next_diff.off_next_version; + if (krb5_storage_seek(sp, left, SEEK_SET) != left) + goto err; + if (kadm5_log_next(context, sp, &ver, NULL, NULL, NULL) == 0 && + ver == s->next_diff.last_version_sent + 1) + return left; + } + + if (krb5_storage_seek(sp, pos, SEEK_SET) != pos) + goto err; + + /* + * Drop the lock and try to find the left entry by seeking backward + * from the end of the end of the log. If we succeed, re-acquire the + * lock, update "next_diff", and retry the fast-path. + */ + flock(log_fd, LOCK_UN); + + /* Slow path: seek backwards, entry by entry, from the end */ + for (;;) { + enum kadm_ops op; + uint32_t len; + + ret = kadm5_log_previous(context, sp, &ver, NULL, &op, &len); + if (ret) + return -1; + left = krb5_storage_seek(sp, -16, SEEK_CUR); + if (left < 0) + return left; + if (ver == s->version + 1) + break; + + /* + * We don't expect to reach the slave's version, unless the log + * has been modified after we released the lock. + */ + if (ver == s->version) { + krb5_warnx(context, "iprop log truncated while sending diffs " + "to slave?? ver = %lu", (unsigned long)ver); + return -1; + } + + /* If we've reached the uber record, send the complete database */ + if (left == 0 || (ver == 0 && op == kadm_nop)) + return 0; + } + assert(ver == s->version + 1); + + /* Set up the fast-path pre-conditions */ + s->next_diff.last_version_sent = s->version; + s->next_diff.off_next_version = left; + s->next_diff.initial_version = *initial_verp; + s->next_diff.initial_tstamp = *initial_timep; + + /* + * If we loop then we're hoping to hit the fast path so we can return a + * non-zero, positive left offset with the lock held. + * + * We just updated the fast path pre-conditions, so unless a log + * truncation event happens between the point where we dropped the lock + * and the point where we rearcuire it above, we will hit the fast + * path. + */ + } + + err: + flock(log_fd, LOCK_UN); + return -1; +} + +static off_t +get_right(krb5_context context, int log_fd, krb5_storage *sp, + int lastver, slave *s, off_t left, uint32_t *verp) +{ + int ret = 0; + int i = 0; + uint32_t ver = s->version; + off_t right = krb5_storage_seek(sp, left, SEEK_SET); + + if (right <= 0) { + flock(log_fd, LOCK_UN); + return -1; + } + + /* The "lastver" bound should preclude us reaching EOF */ + for (; ret == 0 && i < SEND_DIFFS_MAX_RECORDS && ver < lastver; ++i) { + uint32_t logver; + + ret = kadm5_log_next(context, sp, &logver, NULL, NULL, NULL); + if (logver != ++ver) + ret = KADM5_LOG_CORRUPT; + } + + if (ret == 0) + right = krb5_storage_seek(sp, 0, SEEK_CUR); + else + right = -1; + if (right <= 0) { + flock(log_fd, LOCK_UN); + return -1; + } + *verp = ver; + return right; +} + +static void +send_diffs(kadm5_server_context *server_context, slave *s, int log_fd, + const char *database, uint32_t current_version) +{ + krb5_context context = server_context->context; + krb5_storage *sp; + uint32_t initial_version; + uint32_t initial_tstamp; + uint32_t ver; + off_t left = 0; + off_t right = 0; + krb5_ssize_t bytes; + krb5_data data; + int ret = 0; + + if (!diffready(context, s) || nodiffs(context, s, current_version)) + return; + + if (verbose) + krb5_warnx(context, "sending diffs to live-seeming slave %s", s->name); + + sp = krb5_storage_from_fd(log_fd); + if (sp == NULL) + krb5_err(context, IPROPD_RESTART_SLOW, ENOMEM, + "send_diffs: out of memory"); + + left = get_left(server_context, s, sp, log_fd, current_version, + &initial_version, &initial_tstamp); + if (left < 0) { + krb5_storage_free(sp); + slave_dead(context, s); + return; + } + + if (left == 0) { + /* Slave's version is not in the log, fall back on send_complete() */ + krb5_storage_free(sp); + send_complete(context, s, database, current_version, + initial_version, initial_tstamp); + return; + } + + /* We still hold the read lock, if right > 0 */ + right = get_right(server_context->context, log_fd, sp, current_version, + s, left, &ver); + if (right == left) { + flock(log_fd, LOCK_UN); + krb5_storage_free(sp); + return; + } + if (right < left) { + assert(right < 0); + krb5_storage_free(sp); + slave_dead(context, s); + return; + } + + if (krb5_storage_seek(sp, left, SEEK_SET) != left) { + ret = errno ? errno : EIO; + flock(log_fd, LOCK_UN); + krb5_warn(context, ret, "send_diffs: krb5_storage_seek"); + krb5_storage_free(sp); + slave_dead(context, s); + return; + } + + ret = krb5_data_alloc(&data, right - left + 4); + if (ret) { + flock(log_fd, LOCK_UN); + krb5_warn(context, ret, "send_diffs: krb5_data_alloc"); + krb5_storage_free(sp); + slave_dead(context, s); + return; + } + + bytes = krb5_storage_read(sp, (char *)data.data + 4, data.length - 4); + flock(log_fd, LOCK_UN); + krb5_storage_free(sp); + if (bytes != data.length - 4) + krb5_errx(context, IPROPD_RESTART, "locked log truncated???"); + + sp = krb5_storage_from_data(&data); + if (sp == NULL) { + krb5_err(context, IPROPD_RESTART_SLOW, ENOMEM, "out of memory"); + return; + } + krb5_store_uint32(sp, FOR_YOU); + krb5_storage_free(sp); + + ret = mk_priv_tail(context, s, &data); + krb5_data_free(&data); + if (ret == 0) { + /* Save the fast-path continuation */ + s->next_diff.last_version_sent = ver; + s->next_diff.off_next_version = right; + s->next_diff.initial_version = initial_version; + s->next_diff.initial_tstamp = initial_tstamp; + s->next_diff.more = ver < current_version; + ret = send_tail(context, s); + + krb5_warnx(context, + "syncing slave %s from version %lu to version %lu", + s->name, (unsigned long)s->version, + (unsigned long)ver); + s->version = ver; + } + + if (ret && ret != EWOULDBLOCK) { + krb5_warn(context, ret, "send_diffs: making or sending " + "KRB-PRIV message"); + slave_dead(context, s); + return; + } + slave_seen(s); + return; +} + +/* Sensible bound on slave message size */ +#define SLAVE_MSG_MAX 65536 + +static int +fill_input(krb5_context context, slave *s) +{ + krb5_error_code ret; + + if (s->input.hlen < 4) { + uint8_t *buf = s->input.header_buf + s->input.hlen; + size_t len = 4 - s->input.hlen; + krb5_ssize_t bytes = krb5_net_read(context, &s->fd, buf, len); + + if (bytes == 0) + return HEIM_ERR_EOF; + if (bytes < 0) { + if (errno == EWOULDBLOCK || errno == EAGAIN) + return EWOULDBLOCK; + return errno ? errno : EIO; + } + s->input.hlen += bytes; + if (bytes < len) + return EWOULDBLOCK; + + buf = s->input.header_buf; + len = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3]; + if (len > SLAVE_MSG_MAX) + return EINVAL; + ret = krb5_data_alloc(&s->input.packet, len); + if (ret != 0) + return ret; + } + + if (s->input.offset < s->input.packet.length) { + u_char *buf = (u_char *)s->input.packet.data + s->input.offset; + size_t len = s->input.packet.length - s->input.offset; + krb5_ssize_t bytes = krb5_net_read(context, &s->fd, buf, len); + + if (bytes == 0) + return HEIM_ERR_EOF; + if (bytes < 0) { + if (errno == EWOULDBLOCK || errno == EAGAIN) + return EWOULDBLOCK; + return errno ? errno : EIO; + } + s->input.offset += bytes; + if (bytes != len) + return EWOULDBLOCK; + } + return 0; +} + +static int +read_msg(krb5_context context, slave *s, krb5_data *out) +{ + int ret = fill_input(context, s); + + if (ret != 0) + return ret; + + ret = krb5_rd_priv(context, s->ac, &s->input.packet, out, NULL); + + /* Prepare for next packet */ + krb5_data_free(&s->input.packet); + s->input.offset = 0; + s->input.hlen = 0; + + return ret; +} + +static int +process_msg(kadm5_server_context *server_context, slave *s, int log_fd, + const char *database, uint32_t current_version) +{ + krb5_context context = server_context->context; + int ret = 0; + krb5_data out; + krb5_storage *sp; + uint32_t tmp; + + ret = read_msg(context, s, &out); + if (ret) { + if (ret != EWOULDBLOCK) + krb5_warn(context, ret, "error reading message from %s", s->name); + return ret; + } + + 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; + } + /* + * XXX Make the slave send the timestamp as well, and try to get it + * here, and pass it to send_diffs(). + */ + /* + * New slave whose version number we've not yet seen. If the version + * number is zero, the slave has no data, and we'll send a complete + * database (that happens in send_diffs()). Otherwise, we'll record a + * non-zero initial version and attempt an incremental update. + * + * NOTE!: Once the slave is "ready" (its first I_HAVE has conveyed its + * initial version), we MUST NOT update s->version to the slave's + * I_HAVE version, since we may already have sent later updates, and + * MUST NOT send them again, otherwise we can get further and further + * out of sync resending larger and larger diffs. The "not yet ready" + * is an essential precondition for setting s->version to the value + * in the I_HAVE message. This happens only once when the slave + * first connects. + */ + if (!(s->flags & SLAVE_F_READY)) { + if (current_version < tmp) { + krb5_warnx(context, "Slave %s (version %u) has later version " + "than the master (version %u) OUT OF SYNC", + s->name, tmp, current_version); + /* Force send_complete() */ + tmp = 0; + } + /* + * Mark the slave as ready for updates based on incoming signals. + * Prior to the initial I_HAVE, we don't know the slave's version + * number, and MUST not send it anything, since we'll needlessly + * attempt to send the whole database! + */ + s->version = tmp; + s->flags |= SLAVE_F_READY; + if (verbose) + krb5_warnx(context, "slave %s ready for updates from version %u", + s->name, tmp); + } + if ((s->version_ack = tmp) < s->version) + break; + send_diffs(server_context, s, log_fd, database, current_version); + 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; +} + +#define SLAVE_NAME "Name" +#define SLAVE_ADDRESS "Address" +#define SLAVE_VERSION "Version" +#define SLAVE_STATUS "Status" +#define SLAVE_SEEN "Last Seen" + +static void +init_stats_names(krb5_context context) +{ + const char *fn = NULL; + char *buf = NULL; + + if (slave_stats_file) + fn = slave_stats_file; + else if ((fn = krb5_config_get_string(context, NULL, "kdc", + "iprop-stats", NULL)) == NULL) { + if (asprintf(&buf, "%s/slaves-stats", hdb_db_dir(context)) != -1 + && buf != NULL) + fn = buf; + buf = NULL; + } + if (fn != NULL) { + slave_stats_file = fn; + if (asprintf(&buf, "%s.tmp", fn) != -1 && buf != NULL) + slave_stats_temp_file = buf; + } +} + +static void +write_master_down(krb5_context context) +{ + char str[100]; + time_t t = time(NULL); + FILE *fp = NULL; + + if (slave_stats_temp_file != NULL) + fp = fopen(slave_stats_temp_file, "w"); + if (fp == NULL) + return; + krb5_format_time(context, t, str, sizeof(str), TRUE); + fprintf(fp, "master down at %s\n", str); + + if (fclose(fp) != EOF) + rk_rename(slave_stats_temp_file, slave_stats_file); +} + +static void +write_stats(krb5_context context, slave *slaves, uint32_t current_version) +{ + char str[100]; + rtbl_t tbl; + time_t t = time(NULL); + FILE *fp = NULL; + + if (slave_stats_temp_file != NULL) + fp = fopen(slave_stats_temp_file, "w"); + if (fp == NULL) + return; + + krb5_format_time(context, t, str, sizeof(str), TRUE); + fprintf(fp, "Status for slaves, last updated: %s\n\n", str); + + fprintf(fp, "Master version: %lu\n\n", (unsigned long)current_version); + + tbl = rtbl_create(); + if (tbl == NULL) { + fclose(fp); + return; + } + + rtbl_add_column(tbl, SLAVE_NAME, 0); + rtbl_add_column(tbl, SLAVE_ADDRESS, 0); + rtbl_add_column(tbl, SLAVE_VERSION, RTBL_ALIGN_RIGHT); + rtbl_add_column(tbl, SLAVE_STATUS, 0); + rtbl_add_column(tbl, SLAVE_SEEN, 0); + + rtbl_set_prefix(tbl, " "); + rtbl_set_column_prefix(tbl, SLAVE_NAME, ""); + + while (slaves) { + krb5_address addr; + krb5_error_code ret; + rtbl_add_column_entry(tbl, SLAVE_NAME, slaves->name); + ret = krb5_sockaddr2address (context, + (struct sockaddr*)&slaves->addr, &addr); + if(ret == 0) { + krb5_print_address(&addr, str, sizeof(str), NULL); + krb5_free_address(context, &addr); + rtbl_add_column_entry(tbl, SLAVE_ADDRESS, str); + } else + rtbl_add_column_entry(tbl, SLAVE_ADDRESS, "<unknown>"); + + snprintf(str, sizeof(str), "%u", (unsigned)slaves->version_ack); + rtbl_add_column_entry(tbl, SLAVE_VERSION, str); + + if (slaves->flags & SLAVE_F_DEAD) + rtbl_add_column_entry(tbl, SLAVE_STATUS, "Down"); + else + rtbl_add_column_entry(tbl, SLAVE_STATUS, "Up"); + + ret = krb5_format_time(context, slaves->seen, str, sizeof(str), TRUE); + rtbl_add_column_entry(tbl, SLAVE_SEEN, str); + + slaves = slaves->next; + } + + rtbl_format(tbl, fp); + rtbl_destroy(tbl); + + if (fclose(fp) != EOF) + rk_rename(slave_stats_temp_file, slave_stats_file); +} + + +static char sHDB[] = "HDBGET:"; +static char *realm; +static int version_flag; +static int help_flag; +static char *keytab_str = sHDB; +static char *database; +static char *config_file; +static char *port_str; +static int detach_from_console; +static int daemon_child = -1; + +static struct getargs args[] = { + { "config-file", 'c', arg_string, &config_file, NULL, NULL }, + { "realm", 'r', arg_string, &realm, NULL, NULL }, + { "keytab", 'k', arg_string, &keytab_str, + "keytab to get authentication from", "kspec" }, + { "database", 'd', arg_string, &database, "database", "file"}, + { "slave-stats-file", 0, arg_string, rk_UNCONST(&slave_stats_file), + "file for slave status information", "file"}, + { "time-missing", 0, arg_string, rk_UNCONST(&slave_time_missing), + "time before slave is polled for presence", "time"}, + { "time-gone", 0, arg_string, rk_UNCONST(&slave_time_gone), + "time of inactivity after which a slave is considered gone", "time"}, + { "port", 0, arg_string, &port_str, + "port ipropd will listen to", "port"}, + { "detach", 0, arg_flag, &detach_from_console, + "detach from console", NULL }, + { "daemon-child", 0, arg_integer, &daemon_child, + "private argument, do not use", NULL }, + { "pidfile-basename", 0, arg_string, &pidfile_basename, + "basename of pidfile; private argument for testing", "NAME" }, + { "hostname", 0, arg_string, rk_UNCONST(&master_hostname), + "hostname of master (if not same as hostname)", "hostname" }, + { "verbose", 0, arg_flag, &verbose, NULL, NULL }, + { "version", 0, arg_flag, &version_flag, NULL, NULL }, + { "help", 0, arg_flag, &help_flag, NULL, NULL } +}; +static int num_args = sizeof(args) / sizeof(args[0]); + +int +main(int argc, char **argv) +{ + krb5_error_code ret; + krb5_context context; + void *kadm_handle; + kadm5_server_context *server_context; + kadm5_config_params conf; + krb5_socket_t signal_fd, listen_fd; + int log_fd; + slave *slaves = NULL; + uint32_t current_version = 0, old_version = 0; + krb5_keytab keytab; + char **files; + int aret; + int optidx = 0; + int restarter_fd = -1; + struct stat st; + + setprogname(argv[0]); + + if (getarg(args, num_args, argc, argv, &optidx)) + krb5_std_usage(1, args, num_args); + + if (help_flag) + krb5_std_usage(0, args, num_args); + + if (version_flag) { + print_version(NULL); + exit(0); + } + + if (detach_from_console && daemon_child == -1) + daemon_child = roken_detach_prep(argc, argv, "--daemon-child"); + rk_pidfile(pidfile_basename); + + ret = krb5_init_context(&context); + if (ret) + errx(1, "krb5_init_context failed: %d", ret); + + setup_signal(); + + if (config_file == NULL) { + aret = asprintf(&config_file, "%s/kdc.conf", hdb_db_dir(context)); + if (aret == -1 || config_file == NULL) + errx(1, "out of memory"); + } + + ret = krb5_prepend_config_files_default(config_file, &files); + if (ret) + krb5_err(context, 1, ret, "getting configuration files"); + + ret = krb5_set_config_files(context, files); + krb5_free_config_files(files); + if (ret) + krb5_err(context, 1, ret, "reading configuration files"); + + init_stats_names(context); + + time_before_gone = parse_time (slave_time_gone, "s"); + if (time_before_gone < 0) + krb5_errx (context, 1, "couldn't parse time: %s", slave_time_gone); + time_before_missing = parse_time (slave_time_missing, "s"); + if (time_before_missing < 0) + krb5_errx (context, 1, "couldn't parse time: %s", slave_time_missing); + + krb5_openlog(context, "ipropd-master", &log_facility); + krb5_set_warn_dest(context, log_facility); + + ret = krb5_kt_register(context, &hdb_get_kt_ops); + if(ret) + krb5_err(context, 1, ret, "krb5_kt_register"); + + ret = krb5_kt_resolve(context, keytab_str, &keytab); + if(ret) + krb5_err(context, 1, ret, "krb5_kt_resolve: %s", keytab_str); + + memset(&conf, 0, sizeof(conf)); + if(realm) { + conf.mask |= KADM5_CONFIG_REALM; + conf.realm = realm; + } + ret = kadm5_init_with_skey_ctx (context, + KADM5_ADMIN_SERVICE, + NULL, + KADM5_ADMIN_SERVICE, + &conf, 0, 0, + &kadm_handle); + if (ret) + krb5_err (context, 1, ret, "kadm5_init_with_password_ctx"); + + server_context = (kadm5_server_context *)kadm_handle; + + log_fd = open (server_context->log_context.log_file, O_RDONLY, 0); + if (log_fd < 0) + krb5_err (context, 1, errno, "open %s", + server_context->log_context.log_file); + + if (fstat(log_fd, &st) == -1) + krb5_err(context, 1, errno, "stat %s", + server_context->log_context.log_file); + + if (flock(log_fd, LOCK_SH) == -1) + krb5_err(context, 1, errno, "shared flock %s", + server_context->log_context.log_file); + kadm5_log_get_version_fd(server_context, log_fd, LOG_VERSION_LAST, + ¤t_version, NULL); + flock(log_fd, LOCK_UN); + + signal_fd = make_signal_socket (context); + listen_fd = make_listen_socket (context, port_str); + + krb5_warnx(context, "ipropd-master started at version: %lu", + (unsigned long)current_version); + + roken_detach_finish(NULL, daemon_child); + restarter_fd = restarter(context, NULL); + + while (exit_flag == 0){ + slave *p; + fd_set readset, writeset; + int max_fd = 0; + struct timeval to = {30, 0}; + uint32_t vers; + struct stat st2;; + +#ifndef NO_LIMIT_FD_SETSIZE + if (signal_fd >= FD_SETSIZE || listen_fd >= FD_SETSIZE || + restarter_fd >= FD_SETSIZE) + krb5_errx (context, IPROPD_RESTART, "fd too large"); +#endif + + FD_ZERO(&readset); + FD_ZERO(&writeset); + FD_SET(signal_fd, &readset); + max_fd = max(max_fd, signal_fd); + FD_SET(listen_fd, &readset); + max_fd = max(max_fd, listen_fd); + if (restarter_fd > -1) { + FD_SET(restarter_fd, &readset); + max_fd = max(max_fd, restarter_fd); + } + + for (p = slaves; p != NULL; p = p->next) { + if (p->flags & SLAVE_F_DEAD) + continue; + FD_SET(p->fd, &readset); + if (have_tail(p) || more_diffs(p)) + FD_SET(p->fd, &writeset); + max_fd = max(max_fd, p->fd); + } + + ret = select(max_fd + 1, &readset, &writeset, NULL, &to); + if (ret < 0) { + if (errno == EINTR) + continue; + else + krb5_err (context, IPROPD_RESTART, errno, "select"); + } + + if (stat(server_context->log_context.log_file, &st2) == -1) { + krb5_warn(context, errno, "could not stat log file by path"); + st2 = st; + } + + if (st2.st_dev != st.st_dev || st2.st_ino != st.st_ino) { + (void) close(log_fd); + + log_fd = open(server_context->log_context.log_file, O_RDONLY, 0); + if (log_fd < 0) + krb5_err(context, IPROPD_RESTART_SLOW, errno, "open %s", + server_context->log_context.log_file); + + if (fstat(log_fd, &st) == -1) + krb5_err(context, IPROPD_RESTART_SLOW, errno, "stat %s", + server_context->log_context.log_file); + + if (flock(log_fd, LOCK_SH) == -1) + krb5_err(context, IPROPD_RESTART, errno, "shared flock %s", + server_context->log_context.log_file); + kadm5_log_get_version_fd(server_context, log_fd, LOG_VERSION_LAST, + ¤t_version, NULL); + flock(log_fd, LOCK_UN); + } + + if (ret == 0) { + /* Recover from failed transactions */ + if (kadm5_log_init_nb(server_context) == 0) + kadm5_log_end(server_context); + + if (flock(log_fd, LOCK_SH) == -1) + krb5_err(context, IPROPD_RESTART, errno, + "could not lock log file"); + kadm5_log_get_version_fd(server_context, log_fd, LOG_VERSION_LAST, + ¤t_version, NULL); + flock(log_fd, LOCK_UN); + + if (current_version > old_version) { + if (verbose) + krb5_warnx(context, + "Missed a signal, updating slaves %lu to %lu", + (unsigned long)old_version, + (unsigned long)current_version); + for (p = slaves; p != NULL; p = p->next) { + if (p->flags & SLAVE_F_DEAD) + continue; + send_diffs(server_context, p, log_fd, database, + current_version); + } + old_version = current_version; + } + } + + if (ret && FD_ISSET(restarter_fd, &readset)) { + exit_flag = SIGTERM; + break; + } + + if (ret && FD_ISSET(signal_fd, &readset)) { +#ifndef NO_UNIX_SOCKETS + struct sockaddr_un peer_addr; +#else + struct sockaddr_storage peer_addr; +#endif + socklen_t peer_len = sizeof(peer_addr); + + if(recvfrom(signal_fd, (void *)&vers, sizeof(vers), 0, + (struct sockaddr *)&peer_addr, &peer_len) < 0) { + krb5_warn (context, errno, "recvfrom"); + continue; + } + --ret; + assert(ret >= 0); + old_version = current_version; + if (flock(log_fd, LOCK_SH) == -1) + krb5_err(context, IPROPD_RESTART, errno, "shared flock %s", + server_context->log_context.log_file); + kadm5_log_get_version_fd(server_context, log_fd, LOG_VERSION_LAST, + ¤t_version, NULL); + flock(log_fd, LOCK_UN); + if (current_version != old_version) { + /* + * If current_version < old_version then the log got + * truncated and we'll end up doing full propagations. + * + * Truncating the log when the current version is + * numerically small can lead to race conditions. + * Ideally we should identify log versions as + * {init_or_trunc_time, vno}, then we could not have any + * such race conditions, but this would either require + * breaking backwards compatibility for the protocol or + * adding new messages to it. + */ + if (verbose) + krb5_warnx(context, + "Got a signal, updating slaves %lu to %lu", + (unsigned long)old_version, + (unsigned long)current_version); + for (p = slaves; p != NULL; p = p->next) { + if (p->flags & SLAVE_F_DEAD) + continue; + send_diffs(server_context, p, log_fd, database, + current_version); + } + } else { + if (verbose) + krb5_warnx(context, + "Got a signal, but no update in log version %lu", + (unsigned long)current_version); + } + } + + for (p = slaves; p != NULL; p = p->next) { + if (!(p->flags & SLAVE_F_DEAD) && + FD_ISSET(p->fd, &writeset) && + ((have_tail(p) && send_tail(context, p) == 0) || + (!have_tail(p) && more_diffs(p)))) { + send_diffs(server_context, p, log_fd, database, + current_version); + } + } + + for(p = slaves; p != NULL; p = p->next) { + if (p->flags & SLAVE_F_DEAD) + continue; + if (ret && FD_ISSET(p->fd, &readset)) { + --ret; + assert(ret >= 0); + ret = process_msg(server_context, p, log_fd, database, + current_version); + if (ret && ret != EWOULDBLOCK) + slave_dead(context, p); + } else if (slave_gone_p (p)) + slave_dead(context, p); + else if (slave_missing_p (p)) + send_are_you_there (context, p); + } + + if (ret && FD_ISSET(listen_fd, &readset)) { + add_slave (context, keytab, &slaves, listen_fd); + --ret; + assert(ret >= 0); + } + write_stats(context, slaves, current_version); + } + + if(exit_flag == SIGINT || exit_flag == SIGTERM) + krb5_warnx(context, "%s terminated", getprogname()); +#ifdef SIGXCPU + else if(exit_flag == SIGXCPU) + krb5_warnx(context, "%s CPU time limit exceeded", getprogname()); +#endif + else + krb5_warnx(context, "%s unexpected exit reason: %ld", + getprogname(), (long)exit_flag); + + write_master_down(context); + + return 0; +} |