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connect-or-cut.c
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connect-or-cut.c
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/* connect-or-cut -- block unwanted connect() calls.
*
* Copyright Ⓒ 2015-2019 Thomas Girard <[email protected]>
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * 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.
*
* * Neither the name of the author 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 AUTHOR 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 AUTHOR 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.
*/
#define _GNU_SOURCE
#ifndef _WIN32
#include <arpa/inet.h>
#include <dlfcn.h>
#include <fnmatch.h>
#include <netdb.h>
#include <netinet/in.h>
#include <pthread.h>
#include <resolv.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <syslog.h>
#define SOCKET int
#define HOOK(fn) fn
#define WSAAPI /* nothing */
#else
#define _CRT_SECURE_NO_WARNINGS
#include <SDKDDKVer.h>
#define WIN32_LEAN_AND_MEAN
#ifdef COC_EXPORTS
#define COC_API __declspec(dllexport)
#else
#define COC_API __declspec(dllimport)
#endif
#define HOOK(fn) COC_API __stdcall hook_##fn
#include <windows.h>
#include <WinSock2.h>
#include <Ws2tcpip.h>
#include <Shlwapi.h>
#include <iphlpapi.h>
#include "sys_queue.h"
#include "inject.h"
#include "MinHook.h"
#pragma comment(lib, "Ws2_32.lib")
#pragma comment(lib, "shlwapi.lib")
#pragma comment(lib, "IPHLPAPI.lib")
#ifdef _M_X64
#ifdef _DEBUG
#pragma comment(lib, "libMinHook-x64-v140-mtd.lib")
#else
#pragma comment(lib, "libMinHook-x64-v140-mt.lib")
#endif
#elif defined _M_IX86
#ifdef _DEBUG
#pragma comment(lib, "libMinHook-x86-v140-mtd.lib")
#else
#pragma comment(lib, "libMinHook-x86-v140-mt.lib")
#endif
#endif
#endif
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <sys/types.h>
#include <time.h>
#ifdef _WIN32
typedef uint16_t in_port_t;
#define MISSING_STRNDUP
#define MAXNS 30
#define LOG_ERR 3
#define LOG_WARNING 4
#define LOG_INFO 6
#define LOG_DEBUG 7
#define vsyslog(l,f,a) /* Not supported */
#define pthread_testcancel() /* Not supported */
#define localtime_r(ti,tm) localtime_s(tm, ti)
#define fnmatch(p,s,f) (!PathMatchSpecA(s,p))
#endif
#if defined(__APPLE__) && defined(__MACH__)
#include <AvailabilityMacros.h>
#if __MAC_OS_X_VERSION_MAX_ALLOWED < 1070
#define MISSING_STRNDUP
#endif
#endif
#ifdef __SunOS_5_11
#undef MISSING_STRNDUP
#endif
#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
#include <sys/param.h>
#if defined(BSD)
#define HAVE_GETPROGNAME
#endif
#endif
#if (defined(sun) || defined(__sun)) && (defined(__SVR4) || defined(__svr4__))
#define HAVE_GETEXECNAME
#include <libgen.h>
#endif
typedef enum coc_address_type
{
COC_IPV4_ADDR = 1 << 0, /* 1 */
COC_IPV6_ADDR = 1 << 1, /* 2 */
COC_GLOB_ADDR = 1 << 2 /* 4 */
} coc_address_type_t;
#define COC_HOST_ADDR (1 << 3) /* 8 */
typedef enum coc_log_level
{
COC_SILENT_LOG_LEVEL = -1, /* mapped from 0. */
COC_ERROR_LOG_LEVEL = LOG_ERR, /* mapped from 1 (to 3). */
COC_BLOCK_LOG_LEVEL = LOG_WARNING, /* mapped from 2 (to 4). */
COC_ALLOW_LOG_LEVEL = LOG_INFO, /* mapped from 3 (to 6). */
COC_DEBUG_LOG_LEVEL = LOG_DEBUG /* mapped from 4 (to 7). */
} coc_log_level_t;
typedef enum coc_log_target
{
COC_STDERR_LOG = 1 << 0, /* 1 */
COC_SYSLOG_LOG = 1 << 1, /* 2 */
COC_FILE_LOG = 1 << 2 /* 4 */
} coc_log_target_t;
typedef enum coc_rule_type
{
COC_ALLOW = 0,
COC_BLOCK = 1
} coc_rule_type_t;
static const char *rule_type_name[] = {
"ALLOW",
"BLOCK"
};
static const char *address_type_name[] = {
[COC_IPV4_ADDR] = "IPv4",
[COC_IPV6_ADDR] = "IPv6",
[COC_GLOB_ADDR] = "glob",
[COC_HOST_ADDR] = "host"
};
typedef struct coc_entry {
union {
struct in_addr ipv4;
struct in6_addr ipv6;
char *glob;
} addr;
union {
struct in_addr ipv4;
struct in6_addr ipv6;
} netmask;
in_port_t port;
coc_address_type_t addr_type;
coc_rule_type_t rule_type;
SLIST_ENTRY(coc_entry) entries;
bool is_subnet;
} coc_entry_t;
static inline
coc_entry_t *
coc_entry_alloc (void)
{
return (coc_entry_t *) malloc (sizeof(coc_entry_t));
}
SLIST_HEAD(coc_list, coc_entry) coc_list_head = { NULL };
#define COC_ALLOW_ENV_VAR_NAME "COC_ALLOW"
#define COC_BLOCK_ENV_VAR_NAME "COC_BLOCK"
#define COC_LOG_LEVEL_ENV_VAR_NAME "COC_LOG_LEVEL"
#define COC_LOG_PATH_ENV_VAR_NAME "COC_LOG_PATH"
#define COC_LOG_TARGET_ENV_VAR_NAME "COC_LOG_TARGET"
#if defined(__APPLE__) && defined(__MACH__)
#define COC_PRELOAD_ENV_VAR_NAME "DYLD_INSERT_LIBRARIES"
#else
#define COC_PRELOAD_ENV_VAR_NAME "LD_PRELOAD"
#endif
#if defined(HAVE_GETEXECNAME)
static inline const char *
getprogname ()
{
const char *fullpath = getexecname ();
return basename ((char *) fullpath);
}
#elif !defined(HAVE_GETPROGNAME)
#ifdef _WIN32
char __progname[_MAX_FNAME];
#else
extern char *__progname;
#endif
static inline const char *
getprogname ()
{
#ifdef _WIN32
char szThisModule[MAX_PATH] = { 0 };
GetModuleFileNameA(NULL, szThisModule, MAX_PATH);
_splitpath(szThisModule, NULL, NULL, __progname, NULL);
#endif
return __progname;
}
#endif
static const char version[] = "connect-or-cut v1.0.4";
static volatile bool initialized = false;
static bool needs_dns_lookup = false;
static coc_log_level_t log_level = COC_BLOCK_LOG_LEVEL;
static coc_log_target_t log_target = COC_STDERR_LOG;
static char *log_file_name = NULL;
#ifdef __GNUC__
static void
coc_log (coc_log_level_t level, const char *format, ...)
__attribute__ ((__format__ (__printf__, 2, 3)));
#endif
static void
coc_log (coc_log_level_t level, const char *format, ...)
{
if (log_level >= level)
{
struct tm now_tm;
time_t now;
char buffer[sizeof ("YYYY-MM-DDTHH:MM:SS ")];
time (&now);
localtime_r (&now, &now_tm);
strftime (buffer, sizeof (buffer), "%Y-%m-%dT%H:%M:%S ", &now_tm);
if ((log_target & COC_FILE_LOG) == COC_FILE_LOG)
{
va_list ap;
va_start (ap, format);
FILE *log_stream = fopen (log_file_name, "a");
if (!log_stream)
{
fprintf (stderr, "Unable to create log file %s; discarding file logs\n", log_file_name);
log_target &= ~COC_FILE_LOG;
}
else
{
fprintf (log_stream, "%s", buffer);
vfprintf (log_stream, format, ap);
fclose (log_stream);
}
va_end (ap);
}
if ((log_target & COC_STDERR_LOG) == COC_STDERR_LOG)
{
va_list ap;
va_start (ap, format);
fprintf (stderr, "%s", buffer);
vfprintf (stderr, format, ap);
fflush (stderr);
va_end (ap);
}
if ((log_target & COC_SYSLOG_LOG) == COC_SYSLOG_LOG)
{
va_list ap;
va_start (ap, format);
/*
* syslog will be automatically opened at first invocation.
*
* We do not change anything to this because:
* - we know that syslog will not be used during initialization
* of our library
* - the program that will be invoked after our library is
* preloaded can use syslog with non default settings. So
* we reuse these in order not to interfere with the
* program.
*/
vsyslog (level, format, ap);
va_end (ap);
}
}
}
#define DIE(...) do { \
coc_log (COC_ERROR_LOG_LEVEL,"ERROR " __VA_ARGS__); \
exit (EXIT_FAILURE); \
} while (0)
#ifdef MISSING_STRNDUP
static inline char *
strndup (const char *s, size_t n)
{
size_t len = strlen (s);
if (len > n)
{
len = n;
}
char *ns = (char *) malloc (len + 1);
if (ns != NULL)
{
ns[len] = '\0';
memcpy (ns, s, len);
}
return ns;
}
#endif
static inline void
mask_ipv4 (struct in_addr *addr, const struct in_addr *netmask)
{
addr->s_addr &= netmask->s_addr;
}
static inline void
mask_ipv6 (struct in6_addr *addr, const struct in6_addr *netmask)
{
uint32_t *_addr = (uint32_t *) addr;
const uint32_t *_netmask = (uint32_t *) netmask;
int i;
for (i = 0; i < 4; i++)
{
_addr[i] &= _netmask[i];
}
}
static void
make_ipv4_netmask (struct in_addr *netmask, uint8_t cidr_prefix_length)
{
memset (netmask, 0, sizeof(struct in_addr));
if (cidr_prefix_length > 0)
{
netmask->s_addr = htonl (0xFFFFFFFFu << (32u - cidr_prefix_length));
}
}
static void
make_ipv6_netmask (struct in6_addr *netmask, uint8_t cidr_prefix_length)
{
memset (netmask, 0, sizeof(struct in6_addr));
uint8_t *p_netmask = netmask->s6_addr;
while (8 < cidr_prefix_length)
{
*p_netmask = 0xFFu;
p_netmask++;
cidr_prefix_length -= 8;
}
if (cidr_prefix_length > 0)
{
*p_netmask = (0xFFu << (8u - cidr_prefix_length));
}
}
static int
coc_rule_add (const char * const str, const size_t len, const size_t rule_type)
{
int type = COC_IPV4_ADDR | COC_IPV6_ADDR | COC_GLOB_ADDR | COC_HOST_ADDR;
const char *p = str;
const char *service = NULL;
const char *cidr_prefix_length_start = NULL;
enum
{
IPV6_SB_NONE,
IPV6_SB_OPEN,
IPV6_SB_CLOSE
} sb = IPV6_SB_NONE;
size_t colon_count = 0;
size_t ipv4_segment = 1;
uint16_t segment = 0; /* IPv4 or IPv6 */
while (p < str + len)
{
unsigned char c = *p;
/* `*' allowed only for glob. Let's go on to check for errors. */
if (c == '*')
{
/* `*' not allowed if only remaining choices are IPv4 or IPv6. */
if (!(type & ~(COC_IPV4_ADDR | COC_IPV6_ADDR)))
{
DIE ("`*' not allowed for IPv4 or IPv6, aborting\n");
}
else
{
type = COC_GLOB_ADDR;
}
}
/* `[' allowed only at beginning of address for IPv6. */
else if (c == '[')
{
if (p == str)
{
type = COC_IPV6_ADDR;
sb = IPV6_SB_OPEN;
}
else
{
DIE ("`[' allowed only once for IPv6, aborting\n");
}
}
else if (c == ']')
{
if (type == COC_IPV6_ADDR && sb == IPV6_SB_OPEN)
{
sb = IPV6_SB_CLOSE;
}
else
{
DIE ("`]' unexpected, aborting\n");
}
}
else if (c == ':')
{
/* IPv6 uses `:' as a segment separator. So we count them.
* Validation for IPv6 is done later with inet_pton. */
colon_count++;
/* Assume `:' precedes port. We will check if not empty later. */
service = p + 1;
if (colon_count > 1)
{
if ((type & COC_IPV6_ADDR) == COC_IPV6_ADDR)
{
type = COC_IPV6_ADDR;
}
if (type != COC_IPV6_ADDR ||
((sb == IPV6_SB_OPEN && colon_count > 7) ||
colon_count > 8))
{
DIE ("Extra `:' unexpected, aborting\n");
}
if (colon_count == 8 || sb == IPV6_SB_CLOSE)
{
break;
}
else
{
service = NULL;
}
}
else
{
/* If so far IPv4 was still a valid choice, then it is it now. */
if (p != str && ((type & COC_IPV4_ADDR) == COC_IPV4_ADDR))
{
type = COC_IPV4_ADDR;
if (ipv4_segment == 4)
{
break;
}
}
}
}
/* We can see dots for IPv4, glob, or hostnames. We can rule
* out IPv4 when we have a segment that does not fit what is
* expected (e.g. higher than 255).
*/
else if (c == '.')
{
if (type == COC_IPV6_ADDR)
{
DIE ("`.' not allowed for IPv6, aborting\n");
}
type &= ~COC_IPV6_ADDR;
segment = 0;
ipv4_segment++;
if (ipv4_segment > 4)
{
if (type == COC_IPV4_ADDR) /* not possible for now. */
{
DIE ("Extra `.' unexpected, aborting\n");
}
else
{
type &= ~COC_IPV4_ADDR;
}
}
}
else if (isdigit (c))
{
if ((type & COC_IPV4_ADDR) == COC_IPV4_ADDR && cidr_prefix_length_start == NULL)
{
/* INT30-C */
if ((segment > UINT16_MAX / 10) ||
(UINT16_MAX - (c - '0') < segment * 10))
{
DIE ("Invalid IPv4 segment, aborting\n");
}
else
{
segment = segment * 10 + (c - '0');
}
if (segment > 255)
{
if (type == COC_IPV4_ADDR) /* not possible */
{
DIE ("Invalid IPv4 address, aborting\n");
}
else
{
coc_log (COC_DEBUG_LOG_LEVEL,
"DEBUG %hd... is not an IPv4 segment\n",
segment);
type &= ~COC_IPV4_ADDR;
}
}
}
}
else if (isxdigit (c)) /* and not a digit */
{
if (type == COC_IPV4_ADDR) /* not possible */
{
DIE ("Invalid IPv4 address, aborting\n");
}
else
{
type &= ~COC_IPV4_ADDR;
}
}
else if (isalnum (c)) /* not a digit nor an xdigit */
{
if (!(type & ~(COC_IPV4_ADDR | COC_IPV6_ADDR)))
{
DIE ("`%c' unexpected, aborting\n", c);
}
else
{
type &= ~(COC_IPV4_ADDR | COC_IPV6_ADDR);
}
}
else if (c == '-' || c == '_')
{
if (!(type & ~(COC_IPV4_ADDR | COC_IPV6_ADDR)) || p == str)
{
DIE ("`%c' unexpected, aborting\n", c);
}
else
{
type &= ~(COC_IPV4_ADDR | COC_IPV6_ADDR);
}
}
else if (c == '/')
{
if (!(type & (COC_IPV4_ADDR | COC_IPV6_ADDR)) || cidr_prefix_length_start != NULL)
{
DIE ("`%c' unexpected, aborting\n", c);
}
else
{
cidr_prefix_length_start = p + 1;
type &= (COC_IPV4_ADDR | COC_IPV6_ADDR);
}
}
else
{
/* We may revisit this later for UTF-8 */
DIE ("`%c' unexpected here, aborting\n", c);
}
p++;
}
/* If so far IPv4 was still a valid choice, then it is it now. */
if ((type & COC_IPV4_ADDR) == COC_IPV4_ADDR)
{
type = COC_IPV4_ADDR;
}
/* If so far host was still a valid choice, then it is it now. */
else if ((type & COC_HOST_ADDR) == COC_HOST_ADDR)
{
type = COC_HOST_ADDR;
}
if (type == COC_IPV6_ADDR && sb == IPV6_SB_OPEN)
{
DIE ("`]' missing, aborting\n");
}
assert (type == COC_IPV4_ADDR ||
type == COC_IPV6_ADDR ||
type == COC_HOST_ADDR || type == COC_GLOB_ADDR);
in_port_t port = 0;
/* If we have a port here, check if everything after that port is valid. */
if (service != NULL)
{
const char *t = service;
bool getservbyname_needed = false;
if (t == str + len)
{
DIE ("No port specified after `:', aborting\n");
}
while (t < str + len)
{
unsigned char u = *t;
if (isdigit (u))
{
/* INT30-C */
if ((port > UINT16_MAX / 10) ||
(UINT16_MAX - (u - '0') < port * 10))
{
DIE ("Invalid port number, aborting\n");
}
else
{
port = port * 10 + (u - '0');
}
}
else if (isalnum (u) || u == '-')
{
getservbyname_needed = true;
}
else
{
DIE ("`%c' unexpected for port, aborting\n", u);
}
t++;
}
if (getservbyname_needed)
{
#ifdef _WIN32
/* We need to initialize WinSock. It's safe to do so. */
WSADATA wsaData;
int iWSErr = WSAStartup(MAKEWORD(2, 2), &wsaData);
if (iWSErr != 0)
{
DIE("Cannot initialize WinSock 2 API, aborting\n");
}
#endif
char *svc = strndup (service, len - (service - str));
struct servent *svt = getservbyname (svc, "tcp");
if (svt != NULL)
{
port = ntohs (svt->s_port);
free (svc);
#ifdef _WIN32
WSACleanup();
#endif
}
else
{
fprintf (stderr, "service `%s' not found, aborting\n", svc);
free (svc);
#ifdef _WIN32
WSACleanup();
#endif
exit (EXIT_FAILURE);
}
}
if (port == 0)
{
DIE ("`0' not allowed for port, aborting\n");
}
}
uint8_t cidr_prefix_length = 0;
if (cidr_prefix_length_start != NULL)
{
const char *p_end = str + len;
if (service != NULL)
{
p_end = service - 1;
}
if (sb == IPV6_SB_CLOSE)
{
p_end--;
}
if (p_end - cidr_prefix_length_start <= 0)
{
DIE ("No CIDR prefix length specified after `/', aborting\n");
}
else if (p_end - cidr_prefix_length_start > 3)
{
DIE ("Too long CIDR prefix length, aborting\n");
}
const char *t;
for (t = cidr_prefix_length_start; t < p_end; t++)
{
unsigned char u = *t;
if (!isdigit (u))
{
DIE ("`%c' unexpected for CIDR prefix length, aborting\n", u);
}
cidr_prefix_length = cidr_prefix_length * 10 + (u - '0');
}
if ((type == COC_IPV4_ADDR && cidr_prefix_length > 32) ||
(type == COC_IPV6_ADDR && cidr_prefix_length > 128))
{
DIE ("`%u' not allowed for CIDR prefix length, aborting\n", cidr_prefix_length);
}
}
const char *host_start = str;
const char *host_end = host_start + len;
if (service != NULL)
{
host_end = service - 1;
}
if (sb == IPV6_SB_CLOSE)
{
host_start++;
host_end--;
}
if (cidr_prefix_length_start != NULL)
{
host_end = cidr_prefix_length_start - 1;
}
size_t host_len = host_end - host_start;
char *host = strndup (host_start, host_len);
coc_log (COC_DEBUG_LOG_LEVEL,
"DEBUG Adding %s rule for %s connection to %s:%hu\n",
rule_type_name[rule_type], address_type_name[type], host, port);
switch (type)
{
case COC_IPV6_ADDR:
{
coc_entry_t *e = coc_entry_alloc ();
e->rule_type = rule_type;
e->addr_type = COC_IPV6_ADDR;
e->port = htons (port);
e->is_subnet = cidr_prefix_length_start != NULL;
if (inet_pton (AF_INET6, host, &e->addr.ipv6) != 1)
{
DIE ("Invalid IPv6 address: `%s', aborting\n", host);
}
if (e->is_subnet)
{
make_ipv6_netmask (&e->netmask.ipv6, cidr_prefix_length);
mask_ipv6 (&e->addr.ipv6, &e->netmask.ipv6);
}
SLIST_INSERT_HEAD (&coc_list_head, e, entries);
free (host);
break;
}
case COC_IPV4_ADDR:
{
coc_entry_t *e = coc_entry_alloc ();
e->rule_type = rule_type;
e->addr_type = COC_IPV4_ADDR;
e->port = htons (port);
e->is_subnet = cidr_prefix_length_start != NULL;
if (inet_pton (AF_INET, host, &e->addr.ipv4) != 1)
{
DIE ("Invalid IPv4 address: `%s', aborting\n", host);
}
if (e->is_subnet)
{
make_ipv4_netmask (&e->netmask.ipv4, cidr_prefix_length);
mask_ipv4 (&e->addr.ipv4, &e->netmask.ipv4);
}
SLIST_INSERT_HEAD (&coc_list_head, e, entries);
free (host);
break;
}
case COC_GLOB_ADDR:
{
coc_entry_t *e = coc_entry_alloc ();
e->rule_type = rule_type;
e->addr_type = COC_GLOB_ADDR;
e->port = htons (port);
e->is_subnet = false;
/* Here we transfer ownership of `host' to the entry. */
e->addr.glob = host;
SLIST_INSERT_HEAD (&coc_list_head, e, entries);
/* Do not perform DNS lookups for '*' rules. We don't need to. */
if (host[0] != '*' || host[1] != '\0')
{
needs_dns_lookup = true;
}
break;
}
case COC_HOST_ADDR:
{
struct addrinfo *ailist, *aip;
struct addrinfo hints;
int err;
memset (&hints, 0, sizeof(struct addrinfo));
#ifdef AI_ADDRCONFIG
hints.ai_flags |= AI_ADDRCONFIG;
#endif
hints.ai_family = AF_UNSPEC; /* IPv4 or IPv6 or others */
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
#ifdef _WIN32
/* We need to initialize WinSock. It's safe to do so. */
WSADATA wsaData;
int iWSErr = WSAStartup(MAKEWORD(2, 2), &wsaData);
if (iWSErr != 0)
{
DIE("Cannot initialize WinSock 2 API, aborting\n");
}
#endif
if ((err = getaddrinfo (host, NULL, &hints, &ailist)) != 0)
{
DIE ("%s, aborting\n", gai_strerror (err));
}
for (aip = ailist; aip != NULL; aip = aip->ai_next)
{
if (aip->ai_family == AF_INET)
{
struct sockaddr_in *sa = (struct sockaddr_in *) aip->ai_addr;
coc_entry_t *e = coc_entry_alloc ();
e->rule_type = rule_type;
e->addr_type = COC_IPV4_ADDR;
e->port = htons (port);
e->is_subnet = false;
e->addr.ipv4 = sa->sin_addr;
SLIST_INSERT_HEAD (&coc_list_head, e, entries);
}
else if (aip->ai_family == AF_INET6)
{
struct sockaddr_in6 *sa =
(struct sockaddr_in6 *) aip->ai_addr;
coc_entry_t *e = coc_entry_alloc ();
e->rule_type = rule_type;
e->addr_type = COC_IPV6_ADDR;
e->port = htons (port);
e->is_subnet = false;
e->addr.ipv6 = sa->sin6_addr;
SLIST_INSERT_HEAD (&coc_list_head, e, entries);
}
}
freeaddrinfo (ailist);
free (host);
#ifdef _WIN32
WSACleanup();
#endif
break;
}
}
return 0;
}
static size_t
coc_rules_add (const char *rules, size_t rule_type)
{
size_t count = 0;
if (rules)
{
const char *p = rules + strlen (rules);
size_t len = 0;
while (p >= rules)
{
if (*p == ';')
{
if (len > 1)
{
coc_rule_add (p + 1, len - 1, rule_type);
}
len = 1;
count++;
}
else
{
len++;
}
p--;
}
if (len - 1 > 0)
{
coc_rule_add (p + 1, len - 1, rule_type);
count++;
}
}
return count;
}
static long
coc_long_value (const char *name, const char *value, long lower_bound,
long upper_bound)
{
char *endptr;
errno = 0;
long v = strtol (value, &endptr, 10);
if ((errno == ERANGE && (v == LONG_MAX || v == LONG_MIN)) ||
(errno != 0 && value == 0L) ||
*endptr != '\0' || (v < lower_bound || v > upper_bound))
{
DIE ("`%s' not valid for %s (should be between `%ld' and `%ld')\n",
value, name, lower_bound, upper_bound);
}
return v;
}
/* The real connect function. WARNING: cancellation point. */
static int (WSAAPI *real_connect) (SOCKET fd, const struct sockaddr * addr,
socklen_t addrlen);
typedef struct coc_resolver {