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|
/* $OpenBSD: log.c,v 1.51 2005/02/27 13:12:12 hshoexer Exp $ */
/* $EOM: log.c,v 1.30 2000/09/29 08:19:23 niklas Exp $ */
/*
* Copyright (c) 1998, 1999, 2001 Niklas Hallqvist. All rights reserved.
* Copyright (c) 1999, 2000, 2001, 2003 Håkan Olsson. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
/*
* This code was written under funding by Ericsson Radio Systems.
*/
#include <sys/types.h>
#include <sys/time.h>
#ifdef USE_DEBUG
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/udp.h>
#include <arpa/inet.h>
#ifdef HAVE_PCAP
#include <pcap.h>
#else
#include "sysdep/common/pcap.h"
#endif
#endif /* USE_DEBUG */
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <stdarg.h>
#include <unistd.h>
#include "conf.h"
#include "isakmp_num.h"
#include "log.h"
#include "monitor.h"
#include "util.h"
static void _log_print(int, int, const char *, va_list, int, int);
static FILE *log_output;
int verbose_logging = 0;
#if defined (USE_DEBUG)
static int log_level[LOG_ENDCLASS];
#define TCPDUMP_MAGIC 0xa1b2c3d4
#define SNAPLEN (64 * 1024)
struct packhdr {
struct pcap_pkthdr pcap;/* pcap file packet header */
u_int32_t sa_family; /* address family */
union {
struct ip ip4; /* IPv4 header (w/o options) */
struct ip6_hdr ip6; /* IPv6 header */
} ip;
};
struct isakmp_hdr {
u_int8_t icookie[8], rcookie[8];
u_int8_t next, ver, type, flags;
u_int32_t msgid, len;
};
static char *pcaplog_file = NULL;
static FILE *packet_log;
static u_int8_t *packet_buf = NULL;
static int udp_cksum(struct packhdr *, const struct udphdr *,
u_int16_t *);
static u_int16_t in_cksum(const u_int16_t *, int);
#endif /* USE_DEBUG */
void
log_init(int debug)
{
if (debug)
log_output = stderr;
else
log_to(0); /* syslog */
}
void
log_reinit(void)
{
struct conf_list *logging;
#ifdef USE_DEBUG
struct conf_list_node *logclass;
int class, level;
#endif /* USE_DEBUG */
logging = conf_get_list("General", "Logverbose");
if (logging) {
verbose_logging = 1;
conf_free_list(logging);
}
#ifdef USE_DEBUG
logging = conf_get_list("General", "Loglevel");
if (!logging)
return;
for (logclass = TAILQ_FIRST(&logging->fields); logclass;
logclass = TAILQ_NEXT(logclass, link)) {
if (sscanf(logclass->field, "%d=%d", &class, &level) != 2) {
if (sscanf(logclass->field, "A=%d", &level) == 1)
for (class = 0; class < LOG_ENDCLASS; class++)
log_debug_cmd(class, level);
else {
log_print("init: invalid logging class or "
"level: %s", logclass->field);
continue;
}
} else
log_debug_cmd(class, level);
}
conf_free_list(logging);
#endif /* USE_DEBUG */
}
void
log_to(FILE *f)
{
if (!log_output && f)
closelog();
log_output = f;
if (!f)
openlog("isakmpd", LOG_PID | LOG_CONS, LOG_DAEMON);
}
FILE *
log_current(void)
{
return log_output;
}
static char *
_log_get_class(int error_class)
{
/* XXX For test purposes. To be removed later on? */
static char *class_text[] = LOG_CLASSES_TEXT;
if (error_class < 0)
return "Dflt";
else if (error_class >= LOG_ENDCLASS)
return "Unkn";
else
return class_text[error_class];
}
static void
_log_print(int error, int syslog_level, const char *fmt, va_list ap,
int class, int level)
{
char buffer[LOG_SIZE], nbuf[LOG_SIZE + 32];
static const char fallback_msg[] =
"write to log file failed (errno %d), redirecting to syslog";
int len;
struct tm *tm;
struct timeval now;
time_t t;
len = vsnprintf(buffer, sizeof buffer, fmt, ap);
if (len > 0 && len < (int) sizeof buffer - 1 && error)
snprintf(buffer + len, sizeof buffer - len, ": %s",
strerror(errno));
if (log_output) {
gettimeofday(&now, 0);
t = now.tv_sec;
tm = localtime(&t);
if (class >= 0)
snprintf(nbuf, sizeof nbuf,
"%02d%02d%02d.%06ld %s %02d ",
tm->tm_hour, tm->tm_min, tm->tm_sec, now.tv_usec,
_log_get_class(class), level);
else /* LOG_PRINT (-1) or LOG_REPORT (-2) */
snprintf(nbuf, sizeof nbuf, "%02d%02d%02d.%06ld %s ",
tm->tm_hour, tm->tm_min, tm->tm_sec, now.tv_usec,
class == LOG_PRINT ? "Default" : "Report>");
strlcat(nbuf, buffer, sizeof nbuf);
#if defined (USE_PRIVSEP)
strlcat(nbuf, getuid() ? "" : " [priv]", LOG_SIZE + 32);
#endif
strlcat(nbuf, "\n", sizeof nbuf);
if (fwrite(nbuf, strlen(nbuf), 1, log_output) == 0) {
/* Report fallback. */
syslog(LOG_ALERT, fallback_msg, errno);
fprintf(log_output, fallback_msg, errno);
/*
* Close log_output to prevent isakmpd from locking
* the file. We may need to explicitly close stdout
* to do this properly.
* XXX - Figure out how to match two FILE *'s and
* rewrite.
*/
if (fileno(log_output) != -1 &&
fileno(stdout) == fileno(log_output))
fclose(stdout);
fclose(log_output);
/* Fallback to syslog. */
log_to(0);
/* (Re)send current message to syslog(). */
syslog(class == LOG_REPORT ? LOG_ALERT :
syslog_level, "%s", buffer);
}
} else
syslog(class == LOG_REPORT ? LOG_ALERT : syslog_level, "%s",
buffer);
}
#ifdef USE_DEBUG
void
log_debug(int cls, int level, const char *fmt, ...)
{
va_list ap;
/*
* If we are not debugging this class, or the level is too low, just
* return.
*/
if (cls >= 0 && (log_level[cls] == 0 || level > log_level[cls]))
return;
va_start(ap, fmt);
_log_print(0, LOG_INFO, fmt, ap, cls, level);
va_end(ap);
}
void
log_debug_buf(int cls, int level, const char *header, const u_int8_t *buf,
size_t sz)
{
size_t i, j;
char s[73];
/*
* If we are not debugging this class, or the level is too low, just
* return.
*/
if (cls >= 0 && (log_level[cls] == 0 || level > log_level[cls]))
return;
log_debug(cls, level, "%s:", header);
for (i = j = 0; i < sz;) {
snprintf(s + j, sizeof s - j, "%02x", buf[i++]);
j += 2;
if (i % 4 == 0) {
if (i % 32 == 0) {
s[j] = '\0';
log_debug(cls, level, "%s", s);
j = 0;
} else
s[j++] = ' ';
}
}
if (j) {
s[j] = '\0';
log_debug(cls, level, "%s", s);
}
}
void
log_debug_cmd(int cls, int level)
{
if (cls < 0 || cls >= LOG_ENDCLASS) {
log_print("log_debug_cmd: invalid debugging class %d", cls);
return;
}
if (level < 0) {
log_print("log_debug_cmd: invalid debugging level %d for "
"class %d", level, cls);
return;
}
if (level == log_level[cls])
log_print("log_debug_cmd: log level unchanged for class %d",
cls);
else {
log_print("log_debug_cmd: log level changed from %d to %d "
"for class %d", log_level[cls], level, cls);
log_level[cls] = level;
}
}
void
log_debug_toggle(void)
{
static int log_level_copy[LOG_ENDCLASS], toggle = 0;
if (!toggle) {
LOG_DBG((LOG_MISC, 50, "log_debug_toggle: "
"debug levels cleared"));
memcpy(&log_level_copy, &log_level, sizeof log_level);
bzero(&log_level, sizeof log_level);
} else {
memcpy(&log_level, &log_level_copy, sizeof log_level);
LOG_DBG((LOG_MISC, 50, "log_debug_toggle: "
"debug levels restored"));
}
toggle = !toggle;
}
#endif /* USE_DEBUG */
void
log_print(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
_log_print(0, LOG_NOTICE, fmt, ap, LOG_PRINT, 0);
va_end(ap);
}
void
log_verbose(const char *fmt, ...)
{
va_list ap;
#ifdef USE_DEBUG
int i;
#endif /* USE_DEBUG */
if (verbose_logging == 0)
return;
#ifdef USE_DEBUG
for (i = 0; i < LOG_ENDCLASS; i++)
if (log_level[i] > 0)
return;
#endif
va_start(ap, fmt);
_log_print(0, LOG_NOTICE, fmt, ap, LOG_PRINT, 0);
va_end(ap);
}
void
log_error(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
_log_print(1, LOG_ERR, fmt, ap, LOG_PRINT, 0);
va_end(ap);
}
void
log_fatal(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
_log_print(1, LOG_CRIT, fmt, ap, LOG_PRINT, 0);
va_end(ap);
#ifdef USE_PRIVSEP
monitor_exit(1);
#else
exit(1);
#endif
}
#ifdef USE_DEBUG
void
log_packet_init(char *newname)
{
struct pcap_file_header sf_hdr;
struct stat st;
mode_t old_umask;
char *mode;
/* Allocate packet buffer first time through. */
if (!packet_buf)
packet_buf = malloc(SNAPLEN);
if (!packet_buf) {
log_error("log_packet_init: malloc (%d) failed", SNAPLEN);
return;
}
if (pcaplog_file && strcmp(pcaplog_file, PCAP_FILE_DEFAULT) != 0)
free(pcaplog_file);
pcaplog_file = strdup(newname);
if (!pcaplog_file) {
log_error("log_packet_init: strdup (\"%s\") failed", newname);
return;
}
/* Does the file already exist? XXX lstat() or stat()? */
#if defined (USE_PRIVSEP)
/* XXX This is a fstat! */
if (monitor_stat(pcaplog_file, &st) == 0) {
#else
if (lstat(pcaplog_file, &st) == 0) {
#endif
/* Sanity checks. */
if ((st.st_mode & S_IFMT) != S_IFREG) {
log_print("log_packet_init: existing capture file is "
"not a regular file");
return;
}
if ((st.st_mode & (S_IRWXG | S_IRWXO)) != 0) {
log_print("log_packet_init: existing capture "
"file has bad modes");
return;
}
/*
* XXX It would be nice to check if it actually is a pcap
* file...
*/
mode = "a";
} else
mode = "w";
old_umask = umask(S_IRWXG | S_IRWXO);
packet_log = monitor_fopen(pcaplog_file, mode);
umask(old_umask);
if (!packet_log) {
log_error("log_packet_init: fopen (\"%s\", \"%s\") failed",
pcaplog_file, mode);
return;
}
log_print("log_packet_init: "
"starting IKE packet capture to file \"%s\"", pcaplog_file);
/* If this is a new file, we need to write a PCAP header to it. */
if (*mode == 'w') {
sf_hdr.magic = TCPDUMP_MAGIC;
sf_hdr.version_major = PCAP_VERSION_MAJOR;
sf_hdr.version_minor = PCAP_VERSION_MINOR;
sf_hdr.thiszone = 0;
sf_hdr.snaplen = SNAPLEN;
sf_hdr.sigfigs = 0;
sf_hdr.linktype = DLT_LOOP;
fwrite((char *) &sf_hdr, sizeof sf_hdr, 1, packet_log);
fflush(packet_log);
}
}
void
log_packet_restart(char *newname)
{
if (packet_log) {
log_print("log_packet_restart: capture already active on "
"file \"%s\"", pcaplog_file);
return;
}
if (newname)
log_packet_init(newname);
else if (!pcaplog_file)
log_packet_init(PCAP_FILE_DEFAULT);
else
log_packet_init(pcaplog_file);
}
void
log_packet_stop(void)
{
/* Stop capture. */
if (packet_log) {
fclose(packet_log);
log_print("log_packet_stop: stopped capture");
}
packet_log = 0;
}
void
log_packet_iov(struct sockaddr *src, struct sockaddr *dst, struct iovec *iov,
int iovcnt)
{
struct isakmp_hdr *isakmphdr;
struct packhdr hdr;
struct udphdr udp;
struct timeval tv;
int off, datalen, hdrlen, i, add_espmarker = 0;
const u_int32_t espmarker = 0;
for (i = 0, datalen = 0; i < iovcnt; i++)
datalen += iov[i].iov_len;
if (!packet_log || datalen > SNAPLEN)
return;
/* copy packet into buffer */
for (i = 0, off = 0; i < iovcnt; i++) {
memcpy(packet_buf + off, iov[i].iov_base, iov[i].iov_len);
off += iov[i].iov_len;
}
bzero(&hdr, sizeof hdr);
bzero(&udp, sizeof udp);
/* isakmp - turn off the encryption bit in the isakmp hdr */
isakmphdr = (struct isakmp_hdr *) packet_buf;
isakmphdr->flags &= ~(ISAKMP_FLAGS_ENC);
/* udp */
udp.uh_sport = sockaddr_port(src);
udp.uh_dport = sockaddr_port(dst);
datalen += sizeof udp;
#if defined (USE_NAT_TRAVERSAL)
if (ntohs(udp.uh_sport) == 4500 ||
ntohs(udp.uh_dport) == 4500) { /* XXX Quick and dirty */
add_espmarker = 1;
datalen += sizeof espmarker;
}
#endif
udp.uh_ulen = htons(datalen);
/* ip */
hdr.sa_family = htonl(src->sa_family);
switch (src->sa_family) {
default:
/* Assume IPv4. XXX Can 'default' ever happen here? */
hdr.sa_family = htonl(AF_INET);
hdr.ip.ip4.ip_src.s_addr = 0x02020202;
hdr.ip.ip4.ip_dst.s_addr = 0x01010101;
/* The rest of the setup is common to AF_INET. */
goto setup_ip4;
case AF_INET:
hdr.ip.ip4.ip_src.s_addr =
((struct sockaddr_in *)src)->sin_addr.s_addr;
hdr.ip.ip4.ip_dst.s_addr =
((struct sockaddr_in *)dst)->sin_addr.s_addr;
setup_ip4:
hdrlen = sizeof hdr.ip.ip4;
hdr.ip.ip4.ip_v = 0x4;
hdr.ip.ip4.ip_hl = 0x5;
hdr.ip.ip4.ip_p = IPPROTO_UDP;
hdr.ip.ip4.ip_len = htons(datalen + hdrlen);
/* Let's use the IP ID as a "packet counter". */
i = ntohs(hdr.ip.ip4.ip_id) + 1;
hdr.ip.ip4.ip_id = htons(i);
/* Calculate IP header checksum. */
hdr.ip.ip4.ip_sum = in_cksum((u_int16_t *) & hdr.ip.ip4,
hdr.ip.ip4.ip_hl << 2);
break;
case AF_INET6:
hdrlen = sizeof(hdr.ip.ip6);
hdr.ip.ip6.ip6_vfc = IPV6_VERSION;
hdr.ip.ip6.ip6_nxt = IPPROTO_UDP;
hdr.ip.ip6.ip6_plen = udp.uh_ulen;
memcpy(&hdr.ip.ip6.ip6_src,
&((struct sockaddr_in6 *)src)->sin6_addr,
sizeof hdr.ip.ip6.ip6_src);
memcpy(&hdr.ip.ip6.ip6_dst,
&((struct sockaddr_in6 *)dst)->sin6_addr,
sizeof hdr.ip.ip6.ip6_dst);
break;
}
/* Calculate UDP checksum. */
udp.uh_sum = udp_cksum(&hdr, &udp, (u_int16_t *) packet_buf);
hdrlen += sizeof hdr.sa_family;
/* pcap file packet header */
gettimeofday(&tv, 0);
hdr.pcap.ts.tv_sec = tv.tv_sec;
hdr.pcap.ts.tv_usec = tv.tv_usec;
hdr.pcap.caplen = datalen + hdrlen;
hdr.pcap.len = datalen + hdrlen;
hdrlen += sizeof(struct pcap_pkthdr);
datalen -= sizeof(struct udphdr);
/* Write to pcap file. */
fwrite(&hdr, hdrlen, 1, packet_log); /* pcap + IP */
fwrite(&udp, sizeof(struct udphdr), 1, packet_log); /* UDP */
if (add_espmarker) {
fwrite(&espmarker, sizeof espmarker, 1, packet_log);
datalen -= sizeof espmarker;
}
fwrite(packet_buf, datalen, 1, packet_log); /* IKE-data */
fflush(packet_log);
}
/* Copied from tcpdump/print-udp.c, mostly rewritten. */
static int
udp_cksum(struct packhdr *hdr, const struct udphdr *u, u_int16_t *d)
{
struct ip *ip4;
struct ip6_hdr *ip6;
int i, hdrlen, tlen = ntohs(u->uh_ulen) - sizeof(struct udphdr);
union phu {
struct ip4pseudo {
struct in_addr src;
struct in_addr dst;
u_int8_t z;
u_int8_t proto;
u_int16_t len;
} ip4p;
struct ip6pseudo {
struct in6_addr src;
struct in6_addr dst;
u_int32_t plen;
u_int16_t z0;
u_int8_t z1;
u_int8_t nxt;
} ip6p;
u_int16_t pa[20];
} phu;
const u_int16_t *sp;
u_int32_t sum;
/* Setup pseudoheader. */
bzero(phu.pa, sizeof phu);
switch (ntohl(hdr->sa_family)) {
case AF_INET:
ip4 = &hdr->ip.ip4;
memcpy(&phu.ip4p.src, &ip4->ip_src, sizeof(struct in_addr));
memcpy(&phu.ip4p.dst, &ip4->ip_dst, sizeof(struct in_addr));
phu.ip4p.proto = ip4->ip_p;
phu.ip4p.len = u->uh_ulen;
hdrlen = sizeof phu.ip4p;
break;
case AF_INET6:
ip6 = &hdr->ip.ip6;
memcpy(&phu.ip6p.src, &ip6->ip6_src, sizeof(phu.ip6p.src));
memcpy(&phu.ip6p.dst, &ip6->ip6_dst, sizeof(phu.ip6p.dst));
phu.ip6p.plen = u->uh_ulen;
phu.ip6p.nxt = ip6->ip6_nxt;
hdrlen = sizeof phu.ip6p;
break;
default:
return 0;
}
/* IPv6 wants a 0xFFFF checksum "on error", not 0x0. */
if (tlen < 0)
return (ntohl(hdr->sa_family) == AF_INET ? 0 : 0xFFFF);
sum = 0;
for (i = 0; i < hdrlen; i += 2)
sum += phu.pa[i / 2];
sp = (const u_int16_t *)u;
for (i = 0; i < (int)sizeof(struct udphdr); i += 2)
sum += *sp++;
sp = d;
for (i = 0; i < (tlen & ~1); i += 2)
sum += *sp++;
if (tlen & 1)
sum += htons((*(const char *)sp) << 8);
while (sum > 0xffff)
sum = (sum & 0xffff) + (sum >> 16);
sum = ~sum & 0xffff;
return sum;
}
/* Copied from tcpdump/print-ip.c, modified. */
static u_int16_t
in_cksum(const u_int16_t *w, int len)
{
int nleft = len, sum = 0;
u_int16_t answer;
while (nleft > 1) {
sum += *w++;
nleft -= 2;
}
if (nleft == 1)
sum += htons(*(const u_char *)w << 8);
sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */
sum += (sum >> 16); /* add carry */
answer = ~sum; /* truncate to 16 bits */
return answer;
}
#endif /* USE_DEBUG */
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