/* get buflen bytes from proxy server;
handles EINTR;
returns <0 when error occurs
*/
static ssize_t
xioproxy_recvbytes(struct single *xfd, char *buff, size_t buflen, int level) {
ssize_t result;
do {
/* we need at least 16 bytes... */
result = Read(xfd->rfd, buff, buflen);
} while (result < 0 && errno == EINTR); /*! EAGAIN? */
if (result < 0) {
Msg4(level, "read(%d, %p, "F_Zu"): %s",
xfd->rfd, buff, buflen, strerror(errno));
return result;
}
if (result == 0) {
Msg(level, "proxy_connect: connection closed by proxy");
}
return result;
}
/* creates the listening socket, bind, applies options; waits for incoming
connection, checks its source address and port. Depending on fork option, it
may fork a subprocess.
pf specifies the syntax expected for range option. In the case of generic
socket it is 0 (expecting raw binary data), and the real pf can be obtained
from us->af_family; for other socket types pf == us->af_family
Returns 0 if a connection was accepted; with fork option, this is always in
a subprocess!
Other return values indicate a problem; this can happen in the master
process or in a subprocess.
This function does not retry. If you need retries, handle this in a
loop in the calling function (and always provide the options...)
After fork, we set the forever/retry of the child process to 0
applies and consumes the following option:
PH_INIT, PH_PASTSOCKET, PH_PREBIND, PH_BIND, PH_PASTBIND, PH_EARLY,
PH_PREOPEN, PH_FD, PH_CONNECTED, PH_LATE, PH_LATE2
OPT_FORK, OPT_SO_TYPE, OPT_SO_PROTOTYPE, OPT_BACKLOG, OPT_RANGE, tcpwrap,
OPT_SOURCEPORT, OPT_LOWPORT, cloexec
*/
int _xioopen_listen(struct single *xfd, int xioflags, struct sockaddr *us, socklen_t uslen,
struct opt *opts, int pf, int socktype, int proto, int level) {
struct sockaddr sa;
socklen_t salen;
int backlog = 5; /* why? 1 seems to cause problems under some load */
char *rangename;
bool dofork = false;
int maxchildren = 0;
char infobuff[256];
char lisname[256];
union sockaddr_union _peername;
union sockaddr_union _sockname;
union sockaddr_union *pa = &_peername; /* peer address */
union sockaddr_union *la = &_sockname; /* local address */
socklen_t pas = sizeof(_peername); /* peer address size */
socklen_t las = sizeof(_sockname); /* local address size */
int result;
retropt_bool(opts, OPT_FORK, &dofork);
if (dofork) {
if (!(xioflags & XIO_MAYFORK)) {
Error("option fork not allowed here");
return STAT_NORETRY;
}
xfd->flags |= XIO_DOESFORK;
}
retropt_int(opts, OPT_MAX_CHILDREN, &maxchildren);
if (! dofork && maxchildren) {
Error("option max-children not allowed without option fork");
return STAT_NORETRY;
}
if (applyopts_single(xfd, opts, PH_INIT) < 0) return -1;
if (dofork) {
xiosetchilddied(); /* set SIGCHLD handler */
}
if ((xfd->fd = xiosocket(opts, us->sa_family, socktype, proto, level)) < 0) {
return STAT_RETRYLATER;
}
applyopts_cloexec(xfd->fd, opts);
applyopts(xfd->fd, opts, PH_PREBIND);
applyopts(xfd->fd, opts, PH_BIND);
if (Bind(xfd->fd, (struct sockaddr *)us, uslen) < 0) {
Msg4(level, "bind(%d, {%s}, "F_socklen"): %s", xfd->fd,
sockaddr_info(us, uslen, infobuff, sizeof(infobuff)), uslen,
strerror(errno));
Close(xfd->fd);
return STAT_RETRYLATER;
}
#if WITH_UNIX
if (us->sa_family == AF_UNIX) {
applyopts_named(((struct sockaddr_un *)us)->sun_path, opts, PH_FD);
}
#endif
/* under some circumstances (e.g., TCP listen on port 0) bind() fills empty
fields that we want to know. */
salen = sizeof(sa);
if (Getsockname(xfd->fd, us, &uslen) < 0) {
Warn4("getsockname(%d, %p, {%d}): %s",
xfd->fd, &us, uslen, strerror(errno));
}
applyopts(xfd->fd, opts, PH_PASTBIND);
#if WITH_UNIX
if (us->sa_family == AF_UNIX) {
/*applyopts_early(((struct sockaddr_un *)us)->sun_path, opts);*/
applyopts_named(((struct sockaddr_un *)us)->sun_path, opts, PH_EARLY);
applyopts_named(((struct sockaddr_un *)us)->sun_path, opts, PH_PREOPEN);
}
#endif /* WITH_UNIX */
#if WITH_IP4 /*|| WITH_IP6*/
if (retropt_string(opts, OPT_RANGE, &rangename) >= 0) {
if (xioparserange(rangename, pf, &xfd->para.socket.range)
< 0) {
free(rangename);
return STAT_NORETRY;
}
free(rangename);
xfd->para.socket.dorange = true;
}
#endif
#if (WITH_TCP || WITH_UDP) && WITH_LIBWRAP
xio_retropt_tcpwrap(xfd, opts);
#endif /* && (WITH_TCP || WITH_UDP) && WITH_LIBWRAP */
#if WITH_TCP || WITH_UDP
if (retropt_ushort(opts, OPT_SOURCEPORT, &xfd->para.socket.ip.sourceport) >= 0) {
xfd->para.socket.ip.dosourceport = true;
}
retropt_bool(opts, OPT_LOWPORT, &xfd->para.socket.ip.lowport);
#endif /* WITH_TCP || WITH_UDP */
applyopts(xfd->fd, opts, PH_PRELISTEN);
retropt_int(opts, OPT_BACKLOG, &backlog);
if (Listen(xfd->fd, backlog) < 0) {
Error3("listen(%d, %d): %s", xfd->fd, backlog, strerror(errno));
return STAT_RETRYLATER;
}
if (xioopts.logopt == 'm') {
Info("starting accept loop, switching to syslog");
diag_set('y', xioopts.syslogfac); xioopts.logopt = 'y';
} else {
Info("starting accept loop");
}
while (true) { /* but we only loop if fork option is set */
char peername[256];
char sockname[256];
int ps; /* peer socket */
pa = &_peername;
la = &_sockname;
salen = sizeof(struct sockaddr);
do {
/*? int level = E_ERROR;*/
Notice1("listening on %s", sockaddr_info(us, uslen, lisname, sizeof(lisname)));
ps = Accept(xfd->fd, (struct sockaddr *)&sa, &salen);
if (ps >= 0) {
/*0 Info4("accept(%d, %p, {"F_Zu"}) -> %d", xfd->fd, &sa, salen, ps);*/
break; /* success, break out of loop */
}
if (errno == EINTR) {
continue;
}
if (errno == ECONNABORTED) {
Notice4("accept(%d, %p, {"F_socklen"}): %s",
xfd->fd, &sa, salen, strerror(errno));
continue;
}
Msg4(level, "accept(%d, %p, {"F_socklen"}): %s",
xfd->fd, &sa, salen, strerror(errno));
Close(xfd->fd);
return STAT_RETRYLATER;
} while (true);
applyopts_cloexec(ps, opts);
if (Getpeername(ps, &pa->soa, &pas) < 0) {
Warn4("getpeername(%d, %p, {"F_socklen"}): %s",
ps, pa, pas, strerror(errno));
pa = NULL;
}
if (Getsockname(ps, &la->soa, &las) < 0) {
Warn4("getsockname(%d, %p, {"F_socklen"}): %s",
ps, la, las, strerror(errno));
la = NULL;
}
Notice2("accepting connection from %s on %s",
pa?
sockaddr_info(&pa->soa, pas, peername, sizeof(peername)):"NULL",
la?
sockaddr_info(&la->soa, las, sockname, sizeof(sockname)):"NULL");
if (pa != NULL && la != NULL && xiocheckpeer(xfd, pa, la) < 0) {
if (Shutdown(ps, 2) < 0) {
Info2("shutdown(%d, 2): %s", ps, strerror(errno));
}
Close(ps);
continue;
}
if (pa != NULL)
Info1("permitting connection from %s",
sockaddr_info((struct sockaddr *)pa, pas,
infobuff, sizeof(infobuff)));
if (dofork) {
pid_t pid; /* mostly int; only used with fork */
sigset_t mask_sigchld;
/* we must prevent that the current packet triggers another fork;
therefore we wait for a signal from the recent child: USR1
indicates that is has consumed the last packet; CHLD means it has
terminated */
/* block SIGCHLD and SIGUSR1 until parent is ready to react */
sigemptyset(&mask_sigchld);
sigaddset(&mask_sigchld, SIGCHLD);
Sigprocmask(SIG_BLOCK, &mask_sigchld, NULL);
if ((pid = xio_fork(false, level==E_ERROR?level:E_WARN)) < 0) {
Close(xfd->fd);
Sigprocmask(SIG_UNBLOCK, &mask_sigchld, NULL);
return STAT_RETRYLATER;
}
if (pid == 0) { /* child */
pid_t cpid = Getpid();
Sigprocmask(SIG_UNBLOCK, &mask_sigchld, NULL);
Info1("just born: child process "F_pid, cpid);
xiosetenvulong("PID", cpid, 1);
if (Close(xfd->fd) < 0) {
Info2("close(%d): %s", xfd->fd, strerror(errno));
}
xfd->fd = ps;
#if WITH_RETRY
/* !? */
xfd->forever = false; xfd->retry = 0;
level = E_ERROR;
#endif /* WITH_RETRY */
break;
}
/* server: continue loop with listen */
/* shutdown() closes the socket even for the child process, but
close() does what we want */
if (Close(ps) < 0) {
Info2("close(%d): %s", ps, strerror(errno));
}
/* now we are ready to handle signals */
Sigprocmask(SIG_UNBLOCK, &mask_sigchld, NULL);
while (maxchildren) {
if (num_child < maxchildren) break;
Notice("maxchildren are active, waiting");
/* UINT_MAX would even be nicer, but Openindiana works only
with 31 bits */
while (!Sleep(INT_MAX)) ; /* any signal lets us continue */
}
Info("still listening");
} else {
if (Close(xfd->fd) < 0) {
Info2("close(%d): %s", xfd->fd, strerror(errno));
}
xfd->fd = ps;
break;
}
}
applyopts(xfd->fd, opts, PH_FD);
applyopts(xfd->fd, opts, PH_PASTSOCKET);
applyopts(xfd->fd, opts, PH_CONNECTED);
if ((result = _xio_openlate(xfd, opts)) < 0)
return result;
/* set the env vars describing the local and remote sockets */
if (la != NULL) xiosetsockaddrenv("SOCK", la, las, proto);
if (pa != NULL) xiosetsockaddrenv("PEER", pa, pas, proto);
return 0;
}
/* perform socks4 client dialog on existing FD.
Called within fork/retry loop, after connect() */
int _xioopen_socks4_connect(struct single *xfd,
struct socks4 *sockhead,
size_t headlen,
int level) {
ssize_t bytes;
int result;
unsigned char buff[SIZEOF_STRUCT_SOCKS4];
struct socks4 *replyhead = (struct socks4 *)buff;
char *destdomname = NULL;
/* send socks header (target addr+port, +auth) */
#if WITH_MSGLEVEL <= E_INFO
if (ntohl(sockhead->dest) <= 0x000000ff) {
destdomname = strchr(sockhead->userid, '\0')+1;
}
Info11("sending socks4%s request VN=%d DC=%d DSTPORT=%d DSTIP=%d.%d.%d.%d USERID=%s%s%s",
destdomname?"a":"",
sockhead->version, sockhead->action, ntohs(sockhead->port),
((unsigned char *)&sockhead->dest)[0],
((unsigned char *)&sockhead->dest)[1],
((unsigned char *)&sockhead->dest)[2],
((unsigned char *)&sockhead->dest)[3],
sockhead->userid,
destdomname?" DESTNAME=":"",
destdomname?destdomname:"");
#endif /* WITH_MSGLEVEL <= E_INFO */
#if WITH_MSGLEVEL <= E_DEBUG
{
char *msgbuff;
if ((msgbuff = Malloc(3*headlen)) != NULL) {
xiohexdump((const unsigned char *)sockhead, headlen, msgbuff);
Debug1("sending socks4(a) request data %s", msgbuff);
}
}
#endif /* WITH_MSGLEVEL <= E_DEBUG */
if (writefull(xfd->fd, sockhead, headlen) < 0) {
Msg4(level, "write(%d, %p, "F_Zu"): %s",
xfd->fd, sockhead, headlen, strerror(errno));
if (Close(xfd->fd) < 0) {
Info2("close(%d): %s", xfd->fd, strerror(errno));
}
return STAT_RETRYLATER; /* retry complete open cycle */
}
bytes = 0;
Info("waiting for socks reply");
while (bytes >= 0) { /* loop over answer chunks until complete or error */
/* receive socks answer */
do {
result = Read(xfd->fd, buff+bytes, SIZEOF_STRUCT_SOCKS4-bytes);
} while (result < 0 && errno == EINTR);
if (result < 0) {
Msg4(level, "read(%d, %p, "F_Zu"): %s",
xfd->fd, buff+bytes, SIZEOF_STRUCT_SOCKS4-bytes,
strerror(errno));
if (Close(xfd->fd) < 0) {
Info2("close(%d): %s", xfd->fd, strerror(errno));
}
}
if (result == 0) {
Msg(level, "read(): EOF during read of socks reply, peer might not be a socks4 server");
if (Close(xfd->fd) < 0) {
Info2("close(%d): %s", xfd->fd, strerror(errno));
}
return STAT_RETRYLATER;
}
#if WITH_MSGLEVEL <= E_DEBUG
{
char msgbuff[3*SIZEOF_STRUCT_SOCKS4];
* xiohexdump((const unsigned char *)replyhead+bytes, result, msgbuff)
= '\0';
Debug2("received socks4 reply data (offset "F_Zd"): %s", bytes, msgbuff);
}
#endif /* WITH_MSGLEVEL <= E_DEBUG */
bytes += result;
if (bytes == SIZEOF_STRUCT_SOCKS4) {
Debug1("received all "F_Zd" bytes", bytes);
break;
}
Debug2("received %d bytes, waiting for "F_Zu" more bytes",
result, SIZEOF_STRUCT_SOCKS4-bytes);
}
if (result <= 0) { /* we had a problem while reading socks answer */
return STAT_RETRYLATER; /* retry complete open cycle */
}
Info7("received socks reply VN=%u CD=%u DSTPORT=%u DSTIP=%u.%u.%u.%u",
replyhead->version, replyhead->action, ntohs(replyhead->port),
((uint8_t *)&replyhead->dest)[0],
((uint8_t *)&replyhead->dest)[1],
((uint8_t *)&replyhead->dest)[2],
((uint8_t *)&replyhead->dest)[3]);
if (replyhead->version != 0) {
Warn1("socks: reply code version is not 0 (%d)",
replyhead->version);
}
switch (replyhead->action) {
case SOCKS_CD_GRANTED:
/* Notice("socks: connect request succeeded"); */
#if 0
if (Getsockname(xfd->fd, (struct sockaddr *)&us, &uslen) < 0) {
Warn4("getsockname(%d, %p, {%d}): %s",
xfd->fd, &us, uslen, strerror(errno));
}
Notice1("successfully connected from %s via socks4",
sockaddr_info((struct sockaddr *)&us, infobuff, sizeof(infobuff)));
#else
Notice("successfully connected via socks4");
#endif
break;
case SOCKS_CD_FAILED:
Msg(level, "socks: connect request rejected or failed");
return STAT_RETRYLATER;
case SOCKS_CD_NOIDENT:
Msg(level, "socks: ident refused by client");
return STAT_RETRYLATER;
case SOCKS_CD_IDENTFAILED:
Msg(level, "socks: ident failed");
return STAT_RETRYLATER;
default:
Msg1(level, "socks: undefined status %u", replyhead->action);
}
return STAT_OK;
}
int _xioopen_proxy_connect(struct single *xfd,
struct proxyvars *proxyvars,
int level) {
size_t offset;
char request[CONNLEN];
char buff[BUFLEN+1];
#if CONNLEN > BUFLEN
#error not enough buffer space
#endif
char textbuff[2*BUFLEN+1]; /* just for sanitizing print data */
char *eol = buff;
int state;
ssize_t sresult;
/* generate proxy request header - points to final target */
sprintf(request, "CONNECT %s:%u HTTP/1.0\r\n",
proxyvars->targetaddr, proxyvars->targetport);
/* send proxy CONNECT request (target addr+port) */
* xiosanitize(request, strlen(request), textbuff) = '\0';
Info1("sending \"%s\"", textbuff);
/* write errors are assumed to always be hard errors, no retry */
do {
sresult = Write(xfd->wfd, request, strlen(request));
} while (sresult < 0 && errno == EINTR);
if (sresult < 0) {
Msg4(level, "write(%d, %p, "F_Zu"): %s",
xfd->wfd, request, strlen(request), strerror(errno));
if (Close(xfd->wfd) < 0) {
Info2("close(%d): %s", xfd->wfd, strerror(errno));
}
return STAT_RETRYLATER;
}
if (proxyvars->authstring) {
/* send proxy authentication header */
# define XIOAUTHHEAD "Proxy-authorization: Basic "
# define XIOAUTHLEN 27
static const char *authhead = XIOAUTHHEAD;
# define HEADLEN 256
char *header, *next;
/* ...\r\n\0 */
if ((header =
Malloc(XIOAUTHLEN+((strlen(proxyvars->authstring)+2)/3)*4+3))
== NULL) {
return -1;
}
strcpy(header, authhead);
next = xiob64encodeline(proxyvars->authstring,
strlen(proxyvars->authstring),
strchr(header, '\0'));
*next = '\0';
Info1("sending \"%s\\r\\n\"", header);
*next++ = '\r'; *next++ = '\n'; *next++ = '\0';
do {
sresult = Write(xfd->wfd, header, strlen(header));
} while (sresult < 0 && errno == EINTR);
if (sresult < 0) {
Msg4(level, "write(%d, %p, "F_Zu"): %s",
xfd->wfd, header, strlen(header), strerror(errno));
if (Close(xfd->wfd/*!*/) < 0) {
Info2("close(%d): %s", xfd->wfd, strerror(errno));
}
return STAT_RETRYLATER;
}
free(header);
}
Info("sending \"\\r\\n\"");
do {
sresult = Write(xfd->wfd, "\r\n", 2);
} while (sresult < 0 && errno == EINTR);
/*! */
/* request is kept for later error messages */
*strstr(request, " HTTP") = '\0';
/* receive proxy answer; looks like "HTTP/1.0 200 .*\r\nHeaders..\r\n\r\n" */
/* socat version 1 depends on a valid fd for data transfer; address
therefore cannot buffer data. So, to prevent reading beyond the end of
the answer headers, only single bytes are read. puh. */
state = XIOSTATE_HTTP1;
offset = 0; /* up to where the buffer is filled (relative) */
/*eol;*/ /* points to the first lineterm of the current line */
do {
sresult = xioproxy_recvbytes(xfd, buff+offset, 1, level);
if (sresult <= 0) {
state = XIOSTATE_ERROR;
break; /* leave read cycles */
}
switch (state) {
case XIOSTATE_HTTP1:
/* 0 or more bytes of first line received, no '\r' yet */
if (*(buff+offset) == '\r') {
eol = buff+offset;
state = XIOSTATE_HTTP2;
break;
}
if (proxyvars->ignorecr && *(buff+offset) == '\n') {
eol = buff+offset;
state = XIOSTATE_HTTP3;
break;
}
break;
case XIOSTATE_HTTP2:
/* first line received including '\r' */
if (*(buff+offset) != '\n') {
state = XIOSTATE_HTTP1;
break;
}
state = XIOSTATE_HTTP3;
break;
case XIOSTATE_HTTP3:
/* received status (first line) and "\r\n" */
if (*(buff+offset) == '\r') {
state = XIOSTATE_HTTP7;
break;
}
if (proxyvars->ignorecr && *(buff+offset) == '\n') {
state = XIOSTATE_HTTP8;
break;
}
state = XIOSTATE_HTTP4;
break;
case XIOSTATE_HTTP4:
/* within header */
if (*(buff+offset) == '\r') {
eol = buff+offset;
state = XIOSTATE_HTTP5;
break;
}
if (proxyvars->ignorecr && *(buff+offset) == '\n') {
eol = buff+offset;
state = XIOSTATE_HTTP6;
break;
}
break;
case XIOSTATE_HTTP5:
/* within header, '\r' received */
if (*(buff+offset) != '\n') {
state = XIOSTATE_HTTP4;
break;
}
state = XIOSTATE_HTTP6;
break;
case XIOSTATE_HTTP6:
/* received status (first line) and 1 or more headers, "\r\n" */
if (*(buff+offset) == '\r') {
state = XIOSTATE_HTTP7;
break;
}
if (proxyvars->ignorecr && *(buff+offset) == '\n') {
state = XIOSTATE_HTTP8;
break;
}
state = XIOSTATE_HTTP4;
break;
case XIOSTATE_HTTP7:
/* received status (first line), 0 or more headers, "\r\n\r" */
if (*(buff+offset) == '\n') {
state = XIOSTATE_HTTP8;
break;
}
if (*(buff+offset) == '\r') {
if (proxyvars->ignorecr) {
break; /* ignore it, keep waiting for '\n' */
} else {
state = XIOSTATE_HTTP5;
}
break;
}
state = XIOSTATE_HTTP4;
break;
}
++offset;
/* end of status line reached */
if (state == XIOSTATE_HTTP3) {
char *ptr;
/* set a terminating null - on or after CRLF? */
*(buff+offset) = '\0';
* xiosanitize(buff, Min(offset, (sizeof(textbuff)-1)>>1), textbuff)
= '\0';
Info1("proxy_connect: received answer \"%s\"", textbuff);
*eol = '\0';
* xiosanitize(buff, Min(strlen(buff), (sizeof(textbuff)-1)>>1),
textbuff) = '\0';
if (strncmp(buff, "HTTP/1.0 ", 9) &&
strncmp(buff, "HTTP/1.1 ", 9)) {
/* invalid answer */
Msg1(level, "proxy: invalid answer \"%s\"", textbuff);
return STAT_RETRYLATER;
}
ptr = buff+9;
/* skip multiple spaces */
while (*ptr == ' ') ++ptr;
/* HTTP answer */
if (strncmp(ptr, "200", 3)) {
/* not ok */
/* CERN:
"HTTP/1.0 200 Connection established"
"HTTP/1.0 400 Invalid request "CONNECT 10.244.9.3:8080 HTTP/1.0" (unknown method)"
"HTTP/1.0 403 Forbidden - by rule"
"HTTP/1.0 407 Proxy Authentication Required"
Proxy-Authenticate: Basic realm="Squid proxy-caching web server"
> 50 72 6f 78 79 2d 61 75 74 68 6f 72 69 7a 61 74 Proxy-authorizat
> 69 6f 6e 3a 20 42 61 73 69 63 20 61 57 4e 6f 63 ion: Basic aWNoc
> 32 56 73 59 6e 4e 30 4f 6e 4e 30 63 6d 56 75 5a 2VsYnN0OnN0cmVuZ
> 32 64 6c 61 47 56 70 62 51 3d 3d 0d 0a 2dlaGVpbQ==..
b64encode("username:password")
"HTTP/1.0 500 Can't connect to host"
*/
/* Squid:
"HTTP/1.0 400 Bad Request"
"HTTP/1.0 403 Forbidden"
"HTTP/1.0 503 Service Unavailable"
interesting header: "X-Squid-Error: ERR_CONNECT_FAIL 111" */
/* Apache:
"HTTP/1.0 400 Bad Request"
"HTTP/1.1 405 Method Not Allowed"
*/
/* WTE:
"HTTP/1.1 200 Connection established"
"HTTP/1.1 404 Host not found or not responding, errno: 79"
"HTTP/1.1 404 Host not found or not responding, errno: 32"
"HTTP/1.1 404 Host not found or not responding, errno: 13"
*/
/* IIS:
"HTTP/1.1 404 Object Not Found"
*/
ptr += 3;
while (*ptr == ' ') ++ptr;
Msg2(level, "%s: %s", request, ptr);
return STAT_RETRYLATER;
}
/* ok!! */
/* "HTTP/1.0 200 Connection established" */
/*Info1("proxy: \"%s\"", textbuff+13);*/
offset = 0;
} else if (state == XIOSTATE_HTTP6) {
/* end of a header line reached */
char *endp;
/* set a terminating null */
*(buff+offset) = '\0';
endp =
xiosanitize(buff, Min(offset, (sizeof(textbuff)-1)>>1),
textbuff);
*endp = '\0';
Info1("proxy_connect: received header \"%s\"", textbuff);
offset = 0;
}