#if 0 /* -*- mode: c; c-file-style: "gnu"; tab-width: 8; -*-
# This program is easy to compile. For example the following ways:
# $ sh identd.c
# $ sh identd.c -g -DDEBUG
# $ sh identd.c -s -DXXXMULTI
# $ sh identd.c TRG=fake_identd -s -DBIND_ADDRESS=127.0.0.1
# $ sh identd.c CC=cc
# $ sh identd.c CC=egcs -s -fomit-frame-pointer
set -eu
CC= TRG=`basename "$0" .c` OIFS=$IFS
for arg in "$@" ''
do case $arg in TRG=*) TRG=`echo "$arg" | sed 's/TRG=//'`; shift ;;
CC=*) CC=`echo "$arg" | sed 's/CC=//'`; shift ;;
clean) set -x; exec rm -f "$TRG" ;;
readme) set -x; exec sed -n '1,/[e]nd/d;/\*\//q;s/..//p' "$0";;
'') set 0 -s -O2; shift; break ;;
*) break ;;
esac; done
case `uname` in SunOS) L='-lsocket -lnsl' ;; *) L= ;; esac
WARN="-Wall -Wstrict-prototypes -pedantic -Wno-long-long"
WARN="$WARN -Wcast-align -Wpointer-arith " # -Wfloat-equal #-Werror
WARN="$WARN -W -Wwrite-strings -Wcast-qual -Wshadow" # -Wconversion
VERSION=`sed -n '/^ [*] Version / {
s/.*Version \([^ ]*\) *\([^ ]*\).*./\1 (\2)/p; q; }' "$0"`
case $VERSION in '') echo Could not read version information. >&2; exit 1; esac
TRGNAME=`basename "$TRG"`
set -x; exec ${CC:-gcc} $WARN "$@" -DTRG="\"$TRGNAME\"" \
-DVERSION="\"$VERSION\"" -o "$TRG" "$0" $L
exit 1
# */
#endif
/*
* identd.c 2.6 2012-05-31 20:37:27 UTC
*
* Author: Tomi Ollila -- too ät iki fi
*
* Created: Sat Nov 25 15:34:07 EET 1995 too
* Last modified: Thu 31 May 2012 23:37:27 EEST too
*
* This program is standalone 'fake' ident daemon. This program does
* not fork() but is configured to handle up to 20 concurrent connections.
* Since one connection should not last long, if all 20 connections are
* in use, the next connection will close the oldest connection data
* has been read. This way this program is not very vulnerable to so
* called `denial of service' attack, thus making this ideal "identd"
* to be used in a firewall, IP masquerading hosts etc.
*
* Program takes one (or many) arguments, which if exist, determines the
* `user' name(s) that is returned for successful ident query.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* HISTORY
*
* Version 2.6 2012-05-31 20:37:27 UTC
* Applied patches from the wl500g project, including IPv6 support, with
* minor tweaks (patches provided by Daniel Gimpelevich. Thanks).
*
* Version 2.5 $Id: identd.c 862 2006-05-18 14:16:34Z too $
* Minor build and readme updates.
*
* Version 2.4 identd.c 568 2005-09-07 20:18:39Z too
* More compilation warnings options set -- iov.base being non-const
* gives warnings that are hard to avoid...
*
* Version 2.3 identd.c 564 2005-09-06 19:15:20Z too
* Randident code from Matthias Jung tuned in.
*
* Version 2.2 identd.c 12 2004-09-08 21:46:54Z too
* Fixed getservbyname() to look port for "auth" instead of "identd"
* port. This "bug" also revealed port number byte order handling bug,
* which was fixed.
* Now this file is stored in subversion repository -- I entered
* $ svn propset svn:keywords Id identd.c -- let's see how it works...
* ... ``svn propset svn:keywords 'Id Rev' identd.c'' !!!
*
* Revision 2.1 2004/01/15 18:14:42 too
* Made BIND_ADDRESS definable (in compiler command line).
* Added some typecasts (using checked_cast() macro).
* Thanks to Jeffrey D. Wheelhouse for his content.
*
* Revision 2.0 2003/05/05 15:21:01 too
* Major update. Removed fdprintf(); replaced with use of
* writev() and newly added outputstrings().
* Removed many now obsolete defines and converted one to
* constant character string.
* Added one assert() (and left room for more). Did some
* relativily small other adjustments.
*
* Revision 1.7 2002/09/29 07:50:20 too
* No longer chops up to IDSTR_MAX chars, but uses "%.*s" to limit length;
* now works also when XXXMULTI defined.
* Back-hacked self-compilable trick, with more tricks to avoid compiler
* warnings.
* Removed own define of FD_SETSIZE altogether;
* systems has it small to begin with.
* Line '415' (or whatever that is now) fixed. () -> (void) in func def.
* Some fine-tuning.
* Thanks to Cristian for his patches.
*
* Revision 1.6.1 2002-09-28 12:30:29 +0200 cii
* + added defines for IDSTR_MAX, IDENT_SUBSTR, IDSTR_BUFLEN and IDSTR_MAX
* (length limit on the id-string)
* + program arg 1 chopped after IDSTR_MAX characters (when applicable);
* reason is:
* - if the program is called with a relativelly long string as arg 1
* (tested with about 400 chars), a segfault occurs due to an internal
* buffer overflow (buffer space reserved for id-string is 128 chars,
* but never verified)
* - it may trigger buffer overflows in clients
* + put a proper comment at the top of the file
* + sorted out FD_SETSIZE (on Linux it's already defined)
* - moved it down below all the includes
* + added time.h include
* + added some short comments
* + conditionals '{', '}' enclosed
* + variable index -> idx in function closeOldest (killed a warning)
* + splitted multiple statements on a singel line
* + splitted long lines
* + prototypes ending in '()' -> '(void)'; changed by protoize
* + corrected most warnings, but "function declaration isn't a prototype"
* which still occurs on line: 415
* + added IDENT_PORT
* + added IDENT_SUBSTR
*
* Revision 1.6 2002/07/31 16:25:20 too
* Now works when started as root (in Linux). Stupid me, tested
* only starting as an ordinary loser.
*
* Revision 1.5 2002/07/29 14:02:42 too
* Added possibility to have multible reply users, one (pseudo)randomly
* chosen at each time.
*
* Revision 1.4 2001/02/09 08:45:42 too
* Now GID is also changed to nobody/nogroup.
*
* Revision 1.3 2000/06/07 05:55:44 too
* Fixed some Solaris compilation "bugs".
* Changed LOG_PERROR to LOG_CONS
*
* Revision 1.2 1999/07/30 04:08:42 too
* Added printing version string (and exit) with `-V' command line option.
*
* Revision 1.1 1999/04/21 17:23:20 too
* - Writes process id to /var/run/identd.pid.
* - Changes (effective) user id to `nobody' after initialization
* (binding socket etc.).
* - Ignores some signals (HUP and PIPE).
* - Handles some signals that aborts by default. The handler function
* tries to get rid of the pidfile.
*
* Revision 0.9b 1999/04/15 20:45:12 too
* Not so much spaghetti anymore. Added documentation and more replies.
*
* Revision 0.9 1999/04/12 18:30:00 too
* Version for unix systems. Standalone, supports 20 concurrent connections.
* The code is quite a spaghetti. But that does not matter.
*/
#ifdef DEBUG
#undef ndebug
#else
#define ndebug 1
#endif
#include <assert.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <fcntl.h>
#include <signal.h>
#include <syslog.h>
#include <pwd.h>
#include <netdb.h>
#include <sys/syslog.h>
#include <sys/types.h>
#include <sys/time.h>
#include <time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <arpa/inet.h>
#include <sys/uio.h>
#include <endian.h>
#if __BYTE_ORDER == __BIG_ENDIAN
#define IPADDR(a,b,c,d) ((in_addr_t)((a << 24) + (b << 16) + (c << 8) + d))
#define IPPORT(v) ((in_port_t)v)
#define A_x_256(a)((a<<8))
#elif __BYTE_ORDER == __LITTLE_ENDIAN
#define IPADDR(a,b,c,d) (a + (b << 8) + (c << 16) + (d << 24))
#define IPPORT(v) ((in_port_t)((v >> 8) | (v << 8)))
#define A_x_256(a) (a)
#else
#error unknown ENDIAN
#endif
#ifndef __STRING
#define __STRING(x) #x
#endif
/* Let's see how long-lived this is... */
#define __STRINGIFY_MACRO(x) __STRING(x)
#ifndef BIND_ADDRESS
#define BIND_ADDRESS 0.0.0.0
#endif
#ifndef BIND_ADDRESS6
#define BIND_ADDRESS6 ::
#endif
#define IDENT_PORT 113
#define MAXCONNS 20
#define MAXIDLETIME 45
#ifndef USE_UNIX_OS
static const char ident_substr[] = " : USERID : OTHER : ";
#else
static const char ident_substr[] = " : USERID : UNIX : ";
#endif
static const int ident_substr_len = sizeof ident_substr - 1;
#if !defined __cplusplus
typedef enum { false = 0, true = 1 } bool;
#endif
#if (__GNUC__ >= 3)
#define GCCATTR_UNUSED __attribute ((unused))
#define from_type(ft, v) \
__builtin_choose_expr (__builtin_types_compatible_p (typeof (v), ft), \
(v), (void)0)
#define checked_cast(ft, tt, v) \
__builtin_choose_expr (__builtin_types_compatible_p (typeof (v), ft), \
((tt)(v)), (void)0)
#else
#define GCCATTR_UNUSED
#define from_type(ft, v) (v)
#define checked_cast(ft, tt, v) ((tt)(v))
#endif
/* ... */
#define CVP (const void *)
#ifndef DEBUG
#define FCS 2 /* First Connection Socket */
#define TRACE(x, y);
#else
#define FCS 4
#define TRACE(x, y) if (x) printf y
#endif
/* descriptors when debugging:
* 0 = server socket
* 1 = standard output (debugging output)
* 2 = standard error
* 3 = syslog fd (hopefully -- otherwise may work a bit wierdly)
* 4 - 4 + MAXCONNS = connection sockets
*
* descriptors when not debugging
* 0 = server socket
* 1 = syslog fd (hopefully -- otherwise this won't work)
* 2 = connection socket after detached from tty. standard error before that
* 3 - 2 + MAXCONNS = rest connection sockets
*
* To try to make sure that syslog fd is what is "requested", the that fd
* is closed before openlog() call. It can only severely fail if fd 0
* is initially closed.
*/
/*
* FD of the connection is always the index of the connection structure
* in `conns' array + FCS
*/
struct {
char buf[20];
int len;
time_t lasttime;
} conns[MAXCONNS];
/*
* To support multible usernames that can be replied by this fake identd
* define `XXXMULTI' in compilation command line. This doesn't look guite
* pretty, but alternatives looks even uglier.
* XXX NOTE: multi currently only slightly tested XXXX.
*/
#ifdef XXXMULTI
#define IU_IN_STRUCT const char * const * identuserlist; int identusers
#define SET_IU(s, c) do { G.identuserlist = &(s); G.identusers = c; } while (0)
#define IU_IN_USAGESTR "[identuser [identuser2...]]"
#else
#define IU_IN_STRUCT const char * identuser
#define SET_IU(s, c) G.identuser = (s)
#define IU_IN_USAGESTR "[identuser]"
#endif
/* When using global variables, bind those at least to a structure. */
struct {
IU_IN_STRUCT;
fd_set readfds;
int conncnt;
bool randident;
} G;
/*
* Prototypes
*/
static void reply(int s, char * buf);
static void replyError(int s, const char * buf);
static const char * strerrno(void);
static const int one = 1;
static const char * const nobodystr = "nobody";
static const char * alphanum =
"0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
static inline void movefd(int from, int to)
{
TRACE(1, ("movefd(from = %d, to = %d)\n", from, to));
if (from != to)
{
dup2(from, to);
close(from);
}
}
/*
* inetbind() must always return 0 or value < 0.
* ... i.e. this version -- saves need for storage of the return value.
*/
#if 0 /* unused */
static int inetbind(int port)
{
return inetbind(htons(port));
}
#endif
static int inetbind(int ipport)
{
int s, len;
union {
struct sockaddr_in sin4;
struct sockaddr_in6 sin6;
} addr;
close(0);
memset(&addr, 0, sizeof addr);
if ((s = socket(AF_INET6, SOCK_STREAM, 0)) >= 0)
{
len = sizeof addr.sin6;
inet_pton(AF_INET6, __STRINGIFY_MACRO(BIND_ADDRESS6), &addr.sin6.sin6_addr);
addr.sin6.sin6_family = AF_INET6;
addr.sin6.sin6_port = ipport;
}
else
if ((s = socket(AF_INET, SOCK_STREAM, 0)) >= 0)
{
len = sizeof addr.sin4;
addr.sin4.sin_addr.s_addr = inet_addr(__STRINGIFY_MACRO(BIND_ADDRESS));
addr.sin4.sin_family = AF_INET;
addr.sin4.sin_port = ipport;
}
else
{
syslog(LOG_CRIT, "Can not create server socket: %s.", strerrno());
return -1;
}
setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
if (bind(s, (struct sockaddr *)&addr, len) < 0)
{
syslog(LOG_CRIT, "Can not bind() server socket: %s.", strerrno());
return -1;
}
if (listen(s, 5) < 0)
{
syslog(LOG_CRIT, "Can not listen() server socket: %s.", strerrno());
return -1;
}
movefd(s, 0);
return 0;
}
static void deleteConn(int s)
{
int i = s - FCS;
TRACE(1, ("deleteConn(): socket %d, conncnt %d\n", s, G.conncnt));
close(s);
G.conncnt--;
/*
* Most of the time there is 0 connections. Most often that there
* is connections, there is just one connection. When this one connection
* closes, i == G.conncnt = 0 -> no copying.
* When there is more than one connection, the oldest connections closes
* earlier on average. When this happens, the code below starts copying
* the connection structure w/ highest index to the place which which is
* just deleted. This means that the connection structures are no longer
* in chronological order. I'd quess this means that when there is more
* than 1 connection, on average every other connection structure needs
* to be copied over the time all these connections are deleted.
*/
if (i != G.conncnt)
{
memcpy(&conns[i], &conns[G.conncnt], sizeof conns[0]);
movefd(G.conncnt + FCS, s);
}
TRACE(1, ("Clearing fd %d, readfds now 0x%x\n\n",
G.conncnt + FCS, *(int *)&G.readfds));
FD_CLR(G.conncnt + FCS, &G.readfds);
}
static int closeOldest(void)
{
time_t min = conns[0].lasttime;
int idx = 0;
int i;
for (i = 1; i < MAXCONNS; i++)
if (conns[i].lasttime < min)
idx = i;
TRACE(1, ("closeOldest(): index %d, socket %d\n", idx, idx + FCS));
replyError(idx + FCS, "X-SERVER-TOO-BUSY");
close(idx + FCS);
return idx;
}
static int checkInput(char * buf, int len, int l)
{
int i;
for (i = len; i < len + l; i++)
if (buf[i] == '\n')
return 1;
return 0;
}
static int getport(void)
{
struct servent * se;
if ((se = getservbyname("auth", "tcp")) == NULL)
return IPPORT(IDENT_PORT);
else
return se->s_port;
}
static const char * strerrno()
{
#if 1
return strerror(errno);
#else
extern char * sys_errlist[];
return sys_errlist[errno];
#endif
}
#define WriteCS(f, s) write(f, s, sizeof s - 1)
static void writestrings(int fd, const char * str, ...)
{
va_list ap;
va_start(ap, str);
while (str)
{
write(fd, str, strlen(str));
str = va_arg(ap, const char *);
}
va_end(ap);
}
#ifndef DEBUG
static void godaemon(void)
{
switch(fork())
{
case -1: exit(-1);
case 0: close(1); close(2); setsid(); break;
default: exit(0);
}
}
#endif
#ifdef TRG
#define PIDFILE "/var/run/" TRG ".pid"
#else
#define PIDFILE "/var/run/identd.pid"
#endif
static void delpidfile(void)
{
/*
* Usually nobody has no write/delete access to directory /var/run/
* therefore if file cannot be deleted, it is truncated
*/
if (unlink(PIDFILE) < 0)
close(open(PIDFILE, O_WRONLY|O_CREAT|O_TRUNC, 0644));
}
static void handlexitsigs(void)
{
delpidfile();
exit(0);
}
static void writepid(uid_t nobody, uid_t nogrp)
/* May succeed. If not, won't care. */
{
int fd = open(PIDFILE, O_WRONLY|O_CREAT|O_TRUNC, 0664);
char buf[24];
if (fd < 0)
return;
/* we don't use snprintf() here since it is not so portable...*/
/* Anyway, 64-bit integer is at max 20 characters long. */
sprintf(buf, "%d\n", getpid());
buf[23] = '\0';
write(fd, buf, strlen(buf));
fchown(fd, nobody, nogrp);
close(fd);
signal(SIGTERM, (void(*)(int))handlexitsigs);
signal(SIGINT, (void(*)(int))handlexitsigs);
signal(SIGQUIT, (void(*)(int))handlexitsigs);
/* should this handle ILL, ... (see signal(7)) */
}
static void printversion(void)
{
struct iovec iv[4];
iv[0].iov_base = TRG;
iv[0].iov_len = sizeof TRG - 1;
iv[1].iov_base = " ";
iv[1].iov_len = 1;
iv[2].iov_base = VERSION;
iv[2].iov_len = sizeof VERSION - 1;
iv[3].iov_base = ".\n";
iv[3].iov_len = 2;
writev(1, iv, 4);
}
int main(int argc GCCATTR_UNUSED, const char * argv[])
{
uid_t nobody, nogrp;
memset(conns, 0, sizeof conns);
memset(&G, 0, sizeof G);
FD_ZERO(&G.readfds);
FD_SET(0, &G.readfds);
TRACE(1, ("s: `%s', l = %d\n", ident_substr, ident_substr_len));
if (argv[1])
if (argv[1][0] == '-') {
if (argv[1][1] == 'V')
{
printversion();
return 0;
}
else
{
if (argv[1][1] == 'r')
{
G.randident = true;
srand(time(0));
}
else
{
char b[2]; b[0] = argv[1][1]; b[1]= '\0';
writestrings(2, argv[0], ": invalid option -- ", b, ".\n",
"Usage: ", argv[0], " [-rV] ", IU_IN_USAGESTR "\n",
NULL);
return 1;
}
}}
else
SET_IU(argv[1], argc - 1);
else
SET_IU(nobodystr, 1);
#ifndef DEBUG
close(1); /* not debugging, openlog() hopefully uses fd 1. */
#else
close(3); /* debugging, TRACE uses fd 1, openlog() hopefully fd 3 */
#endif
openlog("identd", LOG_CONS, LOG_DAEMON);
{
struct passwd * pw = getpwnam(nobodystr);
if (pw)
{
nobody = pw->pw_uid;
nogrp = pw->pw_gid;
}
else
{
syslog(LOG_CRIT, "Can not find user `nobody': %s,", strerrno());
return -1;
}
}
if (inetbind(getport()) < 0)
return -1;
/* */
{
int i;
for (i = FCS; i < MAXCONNS + FCS; i++)
close(i);
}
#ifdef DEBUG
#ifndef LOG_PERROR
#define LOG_PERROR 0
#endif
openlog("identd", LOG_PERROR, LOG_DAEMON);
#else /* not DEBUG */
godaemon();
openlog("identd", 0, LOG_DAEMON);
close(2);
signal(SIGHUP, SIG_IGN);
#endif /* DEBUG */
signal(SIGPIPE, SIG_IGN); /* connection closed when writing (raises ???) */
writepid(nobody, nogrp);
setegid(nogrp); setgid(nogrp); setuid(nobody); seteuid(nobody);
{
int i;
for (i = 0; i < 4; i++)
{
const char * id = NULL;
unsigned int rv = 0;
switch (i)
{
case 0: rv = (unsigned int)getegid(); id = "egid"; break;
case 1: rv = (unsigned int)getgid(); id = "gid"; break;
case 2: rv = (unsigned int)geteuid(); id = "euid"; break;
case 3: rv = (unsigned int)getuid(); id = "uid"; break;
}
if (rv == 0)
{
syslog(LOG_ERR,
"Can not drop all root privileges (%s) !!! %s !!!",
id, strerrno());
delpidfile();
return -1;
}
}
}
while (2)
{
fd_set rfds = G.readfds;
struct timeval tv = { 15, 0 };
int i;
int tim = time(NULL);
TRACE(1, ("calling select(): n = %d, rfds = 0x%x\n\n",
G.conncnt + FCS, *(int *)&rfds));
select(G.conncnt + FCS, &rfds, NULL, NULL, G.conncnt? &tv: NULL);
for (i = G.conncnt - 1; i >= 0; i--)
{
int s = i + FCS;
if (FD_ISSET(s, &rfds))
{
char * buf = conns[i].buf;
unsigned int len = conns[i].len;
unsigned int l;
TRACE(1, ("data socket fd_isset %d\n", s));
if ((int)(l = read(s, buf + len, sizeof conns[0].buf - len)) > 0)
{
if (checkInput(buf, len, l))
{
reply(s, buf);
goto deleteconn;
}
else if (len + l >= sizeof conns[0].buf)
{
replyError(s, "X-INVALID-REQUEST");
goto deleteconn;
}
else
conns[i].len += l;
}
else
goto deleteconn;
conns[i].lasttime = tim;
continue;
deleteconn:
deleteConn(s);
}
else
{
/* implement as time_after() in linux kernel sources ... */
if (conns[i].lasttime + MAXIDLETIME <= tim)
{
replyError(s, "X-TIMEOUT");
deleteConn(s);
}
}
}
if (FD_ISSET(0, &rfds))
{
int s = accept(0, NULL, 0);
TRACE(1, ("server socket fd_isset, %d accepted\n", s));
if (s < 0)
{
if (errno != EINTR) /* EINTR */
syslog(LOG_ERR, "accept: %s", strerrno());
}
else
{
if (G.conncnt == MAXCONNS)
i = closeOldest();
else
i = G.conncnt++;
movefd(s, i + FCS); /* move if not already there */
FD_SET(i + FCS, &G.readfds);
conns[i].len = 0;
conns[i].lasttime = time(NULL);
}
}
}
}
static int parseAddrs(char * ptr, char ** myaddr, char ** heraddr);
static void replyError(int s, const char * buf)
{
struct iovec iv[3];
iv[0].iov_base = "0, 0 : ERROR : "; iv[0].iov_len = 15;
iv[1].iov_base = buf; iv[1].iov_len = strlen(buf);
iv[2].iov_base = "\r\n"; iv[2].iov_len = 2;
writev(s, iv, 3);
}
static void reply(int s, char * buf)
{
char * myaddr, *heraddr;
myaddr = heraddr = NULL;
if (parseAddrs(buf, &myaddr, &heraddr))
replyError(s, "X-INVALID-REQUEST");
else
{
struct iovec iv[6];
#ifdef XXXMULTI
const char * iul = G.identuserlist[random() % G.identusers];
#endif
iv[0].iov_base = myaddr; iv[0].iov_len = strlen(myaddr);
iv[1].iov_base = ", "; iv[1].iov_len = 2;
iv[2].iov_base = heraddr; iv[2].iov_len = strlen(heraddr);
iv[3].iov_base = checked_cast(const char[], void *, ident_substr);
iv[3].iov_len = ident_substr_len;
#ifdef XXXMULTI
iv[4].iov_base = checked_cast(const char *, void *, iul);
iv[4].iov_len = strlen(iul);
#else
if (G.randident)
{
/* generate random string as reply: */
int i;
char randomstring[8];
int randlen = (random() % 6) + 3; /* random string length 3-8 */
/* have first char letter... */
randomstring[0] = alphanum[10 + random() % 52];
for (i = 1; i < randlen; i++)
randomstring[i] = alphanum[random() % 62];
iv[4].iov_base = checked_cast(char [], void *, randomstring);
iv[4].iov_len = randlen;
}
else
{
/* use usual behaviour */
iv[4].iov_base = checked_cast(const char *, void *, G.identuser);
iv[4].iov_len = strlen(G.identuser);
}
#endif
iv[5].iov_base = "\r\n"; iv[5].iov_len = 2;
writev(s, iv, 6);
}
}
static int chmatch(char c, const char * chars)
{
for (; *chars; chars++)
if (c == *chars)
return 1;
return 0;
}
static int skipchars(char ** p, const char * chars)
{
while (chmatch(**p, chars))
(*p)++;
if (**p == '\r' || **p == '\n')
return 0;
return 1;
}
static int parseAddrs(char * ptr, char ** myaddr, char ** heraddr)
{
/* parse <port-on-server> , <port-on-client> */
if (! skipchars(&ptr, " \t"))
return -1;
*myaddr = ptr;
if (! skipchars(&ptr, "1234567890"))
return -1;
if (! chmatch(*ptr, " \t,"))
return -1;
*ptr++ = '\0';
if (! skipchars(&ptr, " \t,") )
return -1;
*heraddr = ptr;
skipchars(&ptr, "1234567890");
if (! chmatch(*ptr, " \n\r"))
return -1;
*ptr = '\0';
return 0;
}
/* EOF */