diff options
Diffstat (limited to 'contrib/blocklist/bin/blocklistd.c')
| -rw-r--r-- | contrib/blocklist/bin/blocklistd.c | 592 |
1 files changed, 592 insertions, 0 deletions
diff --git a/contrib/blocklist/bin/blocklistd.c b/contrib/blocklist/bin/blocklistd.c new file mode 100644 index 000000000000..03a1dbbf056c --- /dev/null +++ b/contrib/blocklist/bin/blocklistd.c @@ -0,0 +1,592 @@ +/* $NetBSD: blocklistd.c,v 1.10 2025/03/26 17:09:35 christos Exp $ */ + +/*- + * Copyright (c) 2015 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Christos Zoulas. + * + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. + */ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#ifdef HAVE_SYS_CDEFS_H +#include <sys/cdefs.h> +#endif +__RCSID("$NetBSD: blocklistd.c,v 1.10 2025/03/26 17:09:35 christos Exp $"); + +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/queue.h> + +#ifdef HAVE_LIBUTIL_H +#include <libutil.h> +#endif +#ifdef HAVE_UTIL_H +#include <util.h> +#endif +#include <string.h> +#include <signal.h> +#include <netdb.h> +#include <stdio.h> +#include <stdbool.h> +#include <string.h> +#include <inttypes.h> +#include <syslog.h> +#include <ctype.h> +#include <limits.h> +#include <errno.h> +#include <poll.h> +#include <fcntl.h> +#include <err.h> +#include <stdlib.h> +#include <unistd.h> +#include <time.h> +#include <ifaddrs.h> +#include <netinet/in.h> + +#include "bl.h" +#include "internal.h" +#include "conf.h" +#include "run.h" +#include "state.h" +#include "support.h" + +static const char *configfile = _PATH_BLCONF; +static DB *state; +static const char *dbfile = _PATH_BLSTATE; +static sig_atomic_t readconf; +static sig_atomic_t done; +static int vflag; + +static void +sigusr1(int n __unused) +{ + debug++; +} + +static void +sigusr2(int n __unused) +{ + debug--; +} + +static void +sighup(int n __unused) +{ + readconf++; +} + +static void +sigdone(int n __unused) +{ + done++; +} + +static __dead void +usage(int c) +{ + if (c != '?') + warnx("Unknown option `%c'", (char)c); + fprintf(stderr, "Usage: %s [-vdfr] [-c <config>] [-R <rulename>] " + "[-P <sockpathsfile>] [-C <controlprog>] [-D <dbfile>] " + "[-s <sockpath>] [-t <timeout>]\n", getprogname()); + exit(EXIT_FAILURE); +} + +static int +getremoteaddress(bl_info_t *bi, struct sockaddr_storage *rss, socklen_t *rsl) +{ + *rsl = sizeof(*rss); + memset(rss, 0, *rsl); + + if (getpeername(bi->bi_fd, (void *)rss, rsl) != -1) + return 0; + + if (errno != ENOTCONN) { + (*lfun)(LOG_ERR, "getpeername failed (%m)"); + return -1; + } + + if (bi->bi_slen == 0) { + (*lfun)(LOG_ERR, "unconnected socket with no peer in message"); + return -1; + } + + switch (bi->bi_ss.ss_family) { + case AF_INET: + *rsl = sizeof(struct sockaddr_in); + break; + case AF_INET6: + *rsl = sizeof(struct sockaddr_in6); + break; + default: + (*lfun)(LOG_ERR, "bad client passed socket family %u", + (unsigned)bi->bi_ss.ss_family); + return -1; + } + + if (*rsl != bi->bi_slen) { + (*lfun)(LOG_ERR, "bad client passed socket length %u != %u", + (unsigned)*rsl, (unsigned)bi->bi_slen); + return -1; + } + + memcpy(rss, &bi->bi_ss, *rsl); + +#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN + if (*rsl != rss->ss_len) { + (*lfun)(LOG_ERR, + "bad client passed socket internal length %u != %u", + (unsigned)*rsl, (unsigned)rss->ss_len); + return -1; + } +#endif + return 0; +} + +static void +process(bl_t bl) +{ + struct sockaddr_storage rss; + socklen_t rsl; + char rbuf[BUFSIZ]; + bl_info_t *bi; + struct conf c; + struct dbinfo dbi; + struct timespec ts; + + memset(&dbi, 0, sizeof(dbi)); + memset(&c, 0, sizeof(c)); + if (clock_gettime(CLOCK_REALTIME, &ts) == -1) { + (*lfun)(LOG_ERR, "clock_gettime failed (%m)"); + return; + } + + if ((bi = bl_recv(bl)) == NULL) { + (*lfun)(LOG_ERR, "no message (%m)"); + return; + } + + if (getremoteaddress(bi, &rss, &rsl) == -1) + goto out; + + if (debug || bi->bi_msg[0]) { + sockaddr_snprintf(rbuf, sizeof(rbuf), "%a:%p", (void *)&rss); + (*lfun)(bi->bi_msg[0] ? LOG_INFO : LOG_DEBUG, + "processing type=%d fd=%d remote=%s msg=%s uid=%lu gid=%lu", + bi->bi_type, bi->bi_fd, rbuf, + bi->bi_msg, (unsigned long)bi->bi_uid, + (unsigned long)bi->bi_gid); + } + + if (conf_find(bi->bi_fd, bi->bi_uid, &rss, &c) == NULL) { + (*lfun)(LOG_DEBUG, "no rule matched"); + goto out; + } + + + if (state_get(state, &c, &dbi) == -1) + goto out; + + if (debug) { + char b1[128], b2[128]; + (*lfun)(LOG_DEBUG, "%s: initial db state for %s: count=%d/%d " + "last=%s now=%s", __func__, rbuf, dbi.count, c.c_nfail, + fmttime(b1, sizeof(b1), dbi.last), + fmttime(b2, sizeof(b2), ts.tv_sec)); + } + + switch (bi->bi_type) { + case BL_ABUSE: + /* + * If the application has signaled abusive behavior, + * set the number of fails to be one less than the + * configured limit. Fallthrough to the normal BL_ADD + * processing, which will increment the failure count + * to the threshhold, and block the abusive address. + */ + if (c.c_nfail != -1) + dbi.count = c.c_nfail - 1; + /*FALLTHROUGH*/ + case BL_ADD: + dbi.count++; + dbi.last = ts.tv_sec; + if (c.c_nfail != -1 && dbi.count >= c.c_nfail) { + /* + * No point in re-adding the rule. + * It might exist already due to latency in processing + * and removing the rule is the wrong thing to do as + * it allows a window to attack again. + */ + if (dbi.id[0] == '\0') { + int res = run_change("add", &c, + dbi.id, sizeof(dbi.id)); + if (res == -1) + goto out; + } + sockaddr_snprintf(rbuf, sizeof(rbuf), "%a", + (void *)&rss); + (*lfun)(LOG_INFO, + "blocked %s/%d:%d for %d seconds", + rbuf, c.c_lmask, c.c_port, c.c_duration); + } + break; + case BL_DELETE: + if (dbi.last == 0) + goto out; + dbi.count = 0; + dbi.last = 0; + break; + case BL_BADUSER: + /* ignore for now */ + break; + default: + (*lfun)(LOG_ERR, "unknown message %d", bi->bi_type); + } + state_put(state, &c, &dbi); + +out: + close(bi->bi_fd); + + if (debug) { + char b1[128], b2[128]; + (*lfun)(LOG_DEBUG, "%s: final db state for %s: count=%d/%d " + "last=%s now=%s", __func__, rbuf, dbi.count, c.c_nfail, + fmttime(b1, sizeof(b1), dbi.last), + fmttime(b2, sizeof(b2), ts.tv_sec)); + } +} + +static void +update_interfaces(void) +{ + struct ifaddrs *oifas, *nifas; + + if (getifaddrs(&nifas) == -1) + return; + + oifas = ifas; + ifas = nifas; + + if (oifas) + freeifaddrs(oifas); +} + +static void +update(void) +{ + struct timespec ts; + struct conf c; + struct dbinfo dbi; + unsigned int f, n; + char buf[128]; + void *ss = &c.c_ss; + + if (clock_gettime(CLOCK_REALTIME, &ts) == -1) { + (*lfun)(LOG_ERR, "clock_gettime failed (%m)"); + return; + } + +again: + for (n = 0, f = 1; state_iterate(state, &c, &dbi, f) == 1; + f = 0, n++) + { + time_t when = c.c_duration + dbi.last; + if (debug > 1) { + char b1[64], b2[64]; + sockaddr_snprintf(buf, sizeof(buf), "%a:%p", ss); + (*lfun)(LOG_DEBUG, "%s:[%u] %s count=%d duration=%d " + "last=%s " "now=%s", __func__, n, buf, dbi.count, + c.c_duration, fmttime(b1, sizeof(b1), dbi.last), + fmttime(b2, sizeof(b2), ts.tv_sec)); + } + if (c.c_duration == -1 || when >= ts.tv_sec) + continue; + if (dbi.id[0]) { + run_change("rem", &c, dbi.id, 0); + sockaddr_snprintf(buf, sizeof(buf), "%a", ss); + (*lfun)(LOG_INFO, "released %s/%d:%d after %d seconds", + buf, c.c_lmask, c.c_port, c.c_duration); + } + state_del(state, &c); + goto again; + } +} + +static void +addfd(struct pollfd **pfdp, bl_t **blp, size_t *nfd, size_t *maxfd, + const char *path) +{ + bl_t bl = bl_create(true, path, vflag ? vdlog : vsyslog_r); + if (bl == NULL || !bl_isconnected(bl)) + exit(EXIT_FAILURE); + if (*nfd >= *maxfd) { + *maxfd += 10; + *blp = realloc(*blp, sizeof(**blp) * *maxfd); + if (*blp == NULL) + err(EXIT_FAILURE, "malloc"); + *pfdp = realloc(*pfdp, sizeof(**pfdp) * *maxfd); + if (*pfdp == NULL) + err(EXIT_FAILURE, "malloc"); + } + + (*pfdp)[*nfd].fd = bl_getfd(bl); + (*pfdp)[*nfd].events = POLLIN; + (*blp)[*nfd] = bl; + *nfd += 1; +} + +static void +uniqueadd(struct conf ***listp, size_t *nlist, size_t *mlist, struct conf *c) +{ + struct conf **list = *listp; + + if (c->c_name[0] == '\0') + return; + for (size_t i = 0; i < *nlist; i++) { + if (strcmp(list[i]->c_name, c->c_name) == 0) + return; + } + if (*nlist == *mlist) { + *mlist += 10; + void *p = realloc(*listp, *mlist * sizeof(*list)); + if (p == NULL) + err(EXIT_FAILURE, "Can't allocate for rule list"); + list = *listp = p; + } + list[(*nlist)++] = c; +} + +static void +rules_flush(void) +{ + struct conf **list; + size_t nlist, mlist; + + list = NULL; + mlist = nlist = 0; + for (size_t i = 0; i < rconf.cs_n; i++) + uniqueadd(&list, &nlist, &mlist, &rconf.cs_c[i]); + for (size_t i = 0; i < lconf.cs_n; i++) + uniqueadd(&list, &nlist, &mlist, &lconf.cs_c[i]); + + for (size_t i = 0; i < nlist; i++) + run_flush(list[i]); + free(list); +} + +static void +rules_restore(void) +{ + DB *db; + struct conf c; + struct dbinfo dbi; + unsigned int f; + + db = state_open(dbfile, O_RDONLY, 0); + if (db == NULL) { + (*lfun)(LOG_ERR, "Can't open `%s' to restore state (%m)", + dbfile); + return; + } + for (f = 1; state_iterate(db, &c, &dbi, f) == 1; f = 0) { + if (dbi.id[0] == '\0') + continue; + (void)run_change("add", &c, dbi.id, sizeof(dbi.id)); + state_put(state, &c, &dbi); + } + state_close(db); + state_sync(state); +} + +int +main(int argc, char *argv[]) +{ + int c, tout, flags, flush, restore, ret; + const char *spath, **blsock; + size_t nblsock, maxblsock; + + setprogname(argv[0]); + + spath = NULL; + blsock = NULL; + maxblsock = nblsock = 0; + flush = 0; + restore = 0; + tout = 0; + flags = O_RDWR|O_EXCL|O_CLOEXEC; + while ((c = getopt(argc, argv, "C:c:D:dfP:rR:s:t:v")) != -1) { + switch (c) { + case 'C': + controlprog = optarg; + break; + case 'c': + configfile = optarg; + break; + case 'D': + dbfile = optarg; + break; + case 'd': + debug++; + break; + case 'f': + flush++; + break; + case 'P': + spath = optarg; + break; + case 'R': + rulename = optarg; + break; + case 'r': + restore++; + break; + case 's': + if (nblsock >= maxblsock) { + maxblsock += 10; + void *p = realloc(blsock, + sizeof(*blsock) * maxblsock); + if (p == NULL) + err(EXIT_FAILURE, + "Can't allocate memory for %zu sockets", + maxblsock); + blsock = p; + } + blsock[nblsock++] = optarg; + break; + case 't': + tout = atoi(optarg) * 1000; + break; + case 'v': + vflag++; + break; + default: + usage(c); + } + } + + argc -= optind; + if (argc) + usage('?'); + + signal(SIGHUP, sighup); + signal(SIGINT, sigdone); + signal(SIGQUIT, sigdone); + signal(SIGTERM, sigdone); + signal(SIGUSR1, sigusr1); + signal(SIGUSR2, sigusr2); + + openlog(getprogname(), LOG_PID, LOG_DAEMON); + + if (debug) { + lfun = dlog; + if (tout == 0) + tout = 5000; + } else { + if (tout == 0) + tout = 15000; + } + + update_interfaces(); + conf_parse(configfile); + if (flush) { + rules_flush(); + if (!restore) + flags |= O_TRUNC; + } + + struct pollfd *pfd = NULL; + bl_t *bl = NULL; + size_t nfd = 0; + size_t maxfd = 0; + + for (size_t i = 0; i < nblsock; i++) + addfd(&pfd, &bl, &nfd, &maxfd, blsock[i]); + free(blsock); + + if (spath) { + FILE *fp = fopen(spath, "r"); + char *line; + if (fp == NULL) + err(EXIT_FAILURE, "Can't open `%s'", spath); + for (; (line = fparseln(fp, NULL, NULL, NULL, 0)) != NULL; + free(line)) + addfd(&pfd, &bl, &nfd, &maxfd, line); + fclose(fp); + } + if (nfd == 0) + addfd(&pfd, &bl, &nfd, &maxfd, _PATH_BLSOCK); + + state = state_open(dbfile, flags, 0600); + if (state == NULL) + state = state_open(dbfile, flags | O_CREAT, 0600); + if (state == NULL) + return EXIT_FAILURE; + + if (restore) { + if (!flush) + rules_flush(); + rules_restore(); + } + + if (!debug) { + if (daemon(0, 0) == -1) + err(EXIT_FAILURE, "daemon failed"); + if (pidfile(NULL) == -1) + err(EXIT_FAILURE, "Can't create pidfile"); + } + + for (size_t t = 0; !done; t++) { + if (readconf) { + readconf = 0; + conf_parse(configfile); + } + ret = poll(pfd, (nfds_t)nfd, tout); + if (debug) + (*lfun)(LOG_DEBUG, "received %d from poll()", ret); + switch (ret) { + case -1: + if (errno == EINTR) + continue; + (*lfun)(LOG_ERR, "poll (%m)"); + return EXIT_FAILURE; + case 0: + state_sync(state); + break; + default: + for (size_t i = 0; i < nfd; i++) + if (pfd[i].revents & POLLIN) + process(bl[i]); + } + if (t % 100 == 0) + state_sync(state); + if (t % 10000 == 0) + update_interfaces(); + update(); + } + state_close(state); + return 0; +} |