zmap-mark-ii/src/zblocklist.c

264 lines
7.1 KiB
C

/*
* ZMap Copyright 2013 Regents of the University of Michigan
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy
* of the License at http://www.apache.org/licenses/LICENSE-2.0
*/
/*
* ZBlocklist is a simple utility that (1) excludes IP addresses on a specified
* blocklist from being scanned, and (2) ensures the uniqueness of output
* addresses such that no host is scanned twice. ZBlocklist takes in a list
* of addresses on stdin and outputs addresses that are acceptable to scan
* on stdout. The utility uses the blocklist data structures from ZMap for
* checking scan eligibility and a paged bitmap for duplicate prevention.
*/
#define _GNU_SOURCE
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>
#include <assert.h>
#include <sched.h>
#include <errno.h>
#include <pwd.h>
#include <time.h>
#include "../lib/includes.h"
#include "../lib/blocklist.h"
#include "../lib/logger.h"
#include "../lib/pbm.h"
#include "zbopt.h"
// struct zbl_stats {
// uint32_t cidr_entries;
// uint32_t allowed_addrs;
// uint32_t input_addrs;
// uint32_t uniq_input_addrs;
// uint32_t blocked_addrs;
// uint32_t output_addrs;
// uint32_t duplicates;
//};
#undef MIN
#define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
// allow 1mb lines + newline + \0
#define MAX_LINE_LENGTH 1024 * 1024 + 2
static inline char *zmin(char *a, char *b)
{
if (a && !b)
return a;
else if (b && !a)
return b;
else
return MIN(a, b);
}
struct zbl_conf {
char *blocklist_filename;
char *allowlist_filename;
char *log_filename;
int check_duplicates;
int ignore_blocklist_errors;
int ignore_input_errors;
int verbosity;
int disable_syslog;
// struct zbl_stats stats;
};
#define SET_IF_GIVEN(DST, ARG) \
{ \
if (args.ARG##_given) { \
(DST) = args.ARG##_arg; \
}; \
}
#define SET_BOOL(DST, ARG) \
{ \
if (args.ARG##_given) { \
(DST) = 1; \
}; \
}
int main(int argc, char **argv)
{
struct zbl_conf conf;
conf.verbosity = 3;
memset(&conf, 0, sizeof(struct zbl_conf));
int no_dupchk_pres = 0;
conf.ignore_blocklist_errors = 0;
conf.ignore_input_errors = 0;
struct gengetopt_args_info args;
struct cmdline_parser_params *params;
params = cmdline_parser_params_create();
assert(params);
params->initialize = 1;
params->override = 0;
params->check_required = 0;
if (cmdline_parser_ext(argc, argv, &args, params) != 0) {
exit(EXIT_SUCCESS);
}
// Handle help text and version
if (args.help_given) {
cmdline_parser_print_help();
exit(EXIT_SUCCESS);
}
if (args.version_given) {
cmdline_parser_print_version();
exit(EXIT_SUCCESS);
}
// Set the log file and metadata file
if (args.log_file_given) {
conf.log_filename = strdup(args.log_file_arg);
}
if (args.verbosity_given) {
conf.verbosity = args.verbosity_arg;
}
// Blocklist and allowlist
if (args.blocklist_file_given) {
conf.blocklist_filename = strdup(args.blocklist_file_arg);
}
if (args.allowlist_file_given) {
conf.allowlist_filename = strdup(args.allowlist_file_arg);
}
// Read the boolean flags
SET_BOOL(no_dupchk_pres, no_duplicate_checking);
conf.check_duplicates = !no_dupchk_pres;
SET_BOOL(conf.ignore_blocklist_errors, ignore_blocklist_errors);
SET_BOOL(conf.ignore_input_errors, ignore_input_errors);
SET_BOOL(conf.disable_syslog, disable_syslog);
// initialize logging
FILE *logfile = stderr;
if (conf.log_filename) {
logfile = fopen(conf.log_filename, "w");
if (!logfile) {
fprintf(
stderr,
"FATAL: unable to open specified logfile (%s)\n",
conf.log_filename);
exit(1);
}
}
if (log_init(logfile, conf.verbosity, !conf.disable_syslog,
"zblocklist")) {
fprintf(stderr, "FATAL: unable able to initialize logging\n");
exit(1);
}
if (!conf.blocklist_filename && !conf.allowlist_filename) {
log_fatal("zblocklist",
"must specify either a allowlist or blocklist file");
}
// parse blocklist
if (conf.blocklist_filename) {
log_debug("zblocklist", "blocklist file at %s to be used",
conf.blocklist_filename);
} else {
log_debug("zblocklist", "no blocklist file specified");
}
if (conf.blocklist_filename &&
access(conf.blocklist_filename, R_OK) == -1) {
log_fatal("zblocklist",
"unable to read specified blocklist file (%s)",
conf.blocklist_filename);
}
if (conf.allowlist_filename) {
log_debug("zblocklist", "allowlist file at %s to be used",
conf.allowlist_filename);
} else {
log_debug("zblocklist", "no allowlist file specified");
}
if (conf.allowlist_filename &&
access(conf.allowlist_filename, R_OK) == -1) {
log_fatal("zblocklist",
"unable to read specified allowlist file (%s)",
conf.allowlist_filename);
}
if (blocklist_init(conf.allowlist_filename, conf.blocklist_filename,
NULL, 0, NULL, 0, conf.ignore_blocklist_errors)) {
log_fatal("zmap", "unable to initialize blocklist / allowlist");
}
// initialize paged bitmap
uint8_t **seen = NULL;
if (conf.check_duplicates) {
seen = pbm_init();
if (!seen) {
log_fatal("zblocklist",
"unable to initialize paged bitmap");
}
}
// process addresses
char *line = malloc(MAX_LINE_LENGTH);
assert(line);
char *original = malloc(MAX_LINE_LENGTH);
assert(original);
while (fgets(line, MAX_LINE_LENGTH, stdin) != NULL) {
size_t len = strlen(line);
if (len >= (MAX_LINE_LENGTH - 1)) {
log_fatal("zblocklist",
"received line longer than max length: %i",
MAX_LINE_LENGTH);
}
// remove new line
memcpy(original, line, len + 1);
char *n =
zmin(zmin(zmin(zmin(strchr(line, '\n'), strchr(line, ',')),
strchr(line, '\t')),
strchr(line, ' ')),
strchr(line, '#'));
assert(n);
n[0] = 0;
log_debug("zblocklist", "input value %s", line);
// parse into int
struct in_addr addr;
if (!inet_aton(line, &addr)) {
log_warn("zblocklist", "invalid input address: %s",
line);
if (!conf.ignore_input_errors) {
printf("%s", original);
}
continue;
}
if (conf.check_duplicates) {
if (pbm_check(seen, ntohl(addr.s_addr))) {
log_debug("zblocklist",
"%s is a duplicate: skipped", line);
continue;
} else {
log_debug("zblocklist",
"%s not a duplicate: skipped", line);
}
} else {
log_debug("zblocklist", "no duplicate checking for %s",
line);
}
// check if in blocklist
if (blocklist_is_allowed(addr.s_addr)) {
if (conf.check_duplicates) {
if (!pbm_check(seen, ntohl(addr.s_addr))) {
pbm_set(seen, ntohl(addr.s_addr));
printf("%s", original);
}
} else {
printf("%s", original);
}
}
}
return EXIT_SUCCESS;
}