[doldaconnect.git] / daemon / fnet-adc.c

/*
 *  Dolda Connect - Modular multiuser Direct Connect-style client
 *  Copyright (C) 2004 Fredrik Tolf <fredrik@dolda2000.com>
 *  
 *  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 of the License, 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.
 *  
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdarg.h>
#include <string.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <wctype.h>
#include <iconv.h>
#include <errno.h>

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "filenet.h"
#include "log.h"
#include "module.h"
#include "utils.h"
#include "client.h"
#include "transfer.h"
#include "sysevents.h"
#include "net.h"
#include <tiger.h>

/* Protocol states */
#define ADC_PROTOCOL 0
#define ADC_IDENTIFY 1
#define ADC_VERIFY 2
#define ADC_NORMAL 3
#define ADC_DATA 4

struct command {
    wchar_t *name;
    int minargs, needsid, needsender;
    void (*func)(struct fnetnode *fn, wchar_t *command, wchar_t *sender, int argc, wchar_t **argv);
};

struct qcmd {
    struct qcmd *next;
    wchar_t **args;
};

struct qcmdqueue {
    struct qcmd *f, *l;
    int size;
};

struct adchub {
    struct socket *sk;
    char *inbuf;
    size_t inbufdata, inbufsize;
    wchar_t *sid;
    wchar_t *cb;
    size_t cbdata, cbsize;
    wchar_t **sup;
    iconv_t ich;
    int state;
    struct wcspair *hubinf;
    struct qcmdqueue queue;
};

static wchar_t *eoc, *ns, *fmt;
/* I've never understood why both of these are necessary, but... */
static wchar_t *privid, *cid;
struct socket *udpsock, *tcpsock;

static wchar_t **parseadc(wchar_t *cmdline)
{
    wchar_t **ret;
    size_t retsize, retdata;
    wchar_t *p, *p2, *ep;
    wchar_t r;
    ssize_t len;
    
    ret = NULL;
    retsize = retdata = 0;
    p = cmdline;
    do {
	if((p2 = wcschr(p, L' ')) != NULL)
	    *(p2++) = L'\0';
	len = wcslen(p);
	for(ep = p; len > 0; ep++, len--) {
	    if(*ep == L'\\') {
		if(ep[1] == L's') {
		    r = L' ';
		} else if(ep[1] == L'n') {
		    r = L'\n';
		} else if(ep[1] == L'\\') {
		    r = L'\\';
		} else {
		    memmove(ep, ep + 2, (len -= 2) * sizeof(*ep));
		    ep--;
		    continue;
		}
		memmove(ep, ep + 1, --len * sizeof(*ep));
		*ep = r;
	    }
	}
	*ep = L'\0';
	addtobuf(ret, swcsdup(p));
	p = p2;
    } while(p2 != NULL);
    addtobuf(ret, NULL);
    return(ret);
}

static void sendeoc(struct socket *sk)
{
    sockqueue(sk, "\n", 1);
}

static void sendadc1(struct socket *sk, int sep, wchar_t *arg)
{
    char *mbsbuf;
    wchar_t *buf;
    size_t bufsize, bufdata;
    
    buf = NULL;
    bufsize = bufdata = 0;
    if(sep)
	addtobuf(buf, L' ');
    for(; *arg != L'\0'; arg++) {
	if(*arg == L' ')
	    bufcat(buf, L"\\s", 2);
	else if(*arg == L'\n')
	    bufcat(buf, L"\\n", 2);
	else if(*arg == L'\\')
	    bufcat(buf, L"\\\\", 2);
	else
	    addtobuf(buf, *arg);
    }
    addtobuf(buf, L'\0');
    mbsbuf = icwcstombs(buf, "utf-8");
    sockqueue(sk, mbsbuf, strlen(mbsbuf));
    free(mbsbuf);
}

static void sendadc(struct socket *sk, int sep, ...)
{
    int i;
    va_list args;
    wchar_t *arg;
    wchar_t *type, *buf;
    
    va_start(args, sep);
    for(i = 0; (arg = va_arg(args, wchar_t *)) != NULL; i++) {
	if(arg == eoc) {
	    sendeoc(sk);
	} else if(arg == ns) {
	    sep = 0;
	} else if(arg == fmt) {
	    type = va_arg(args, wchar_t *);
	    if(!wcscmp(type, L"i")) {
		buf = swprintf2(L"%i", va_arg(args, int));
	    } else if(!wcscmp(type, L"mi")) {
		buf = swprintf2(L"%ji", va_arg(args, intmax_t));
	    }
	    sendadc1(sk, sep, buf);
	    free(buf);
	    sep = 1;
	} else {
	    sendadc1(sk, sep, arg);
	    sep = 1;
	}
    }
    va_end(args);
}

static wchar_t *findkv(wchar_t **argv, wchar_t *name)
{
    while(*argv != NULL) {
	if(!wcsncmp(*argv, name, 2))
	    return((*argv) + 2);
    }
    return(NULL);
}

static struct qcmd *newqcmd(struct qcmdqueue *queue, wchar_t **args)
{
    struct qcmd *new;
    
    new = smalloc(sizeof(*new));
    new->next = NULL;
    new->args = args;
    if(queue->l == NULL)
	queue->f = new;
    else
	queue->l->next = new;
    queue->l = new;
    queue->size++;
    return(new);
}

static struct qcmd *ulqcmd(struct qcmdqueue *queue)
{
    struct qcmd *ret;
    
    if((ret = queue->f) == NULL)
	return(NULL);
    if((queue->f = ret->next) == NULL)
	queue->l = NULL;
    queue->size--;
    return(ret);
}

static void freeqcmd(struct qcmd *qcmd)
{
    freeparr(qcmd->args);
    free(qcmd);
}

static void sendinf(struct fnetnode *fn)
{
    struct adchub *hub = fn->data;
    struct socket *sk = hub->sk;
    struct sockaddr_in *a4;
    socklen_t alen;
    
    sendadc(sk, 0, L"BINF", hub->sid, NULL);
    sendadc(sk, 1, L"PD", ns, privid, L"ID", ns, cid, NULL);
    sendadc(sk, 1, L"VEDolda ", ns, icsmbstowcs(VERSION, "us-ascii", NULL), NULL);
    sendadc(sk, 1, L"NI", ns, fn->mynick, NULL);
    sendadc(sk, 1, L"SS", ns, fmt, L"mi", (intmax_t)sharesize, L"SF", ns, fmt, L"i", sharedfiles, NULL);
    if(sk->family == AF_INET)
	sendadc(sk, 1, L"I40.0.0.0", NULL);
    else if(sk->family == AF_INET6)
	sendadc(sk, 1, L"I6::", NULL);
    sendadc(sk, 1, L"SL", ns, fmt, L"i", confgetint("transfer", "slot"), NULL);
    if(tcpsock != NULL) {
	if((sk->family == AF_INET) && !sockgetremotename(udpsock, (struct sockaddr **)&a4, &alen)) {
	    sendadc(sk, 1, L"U4", ns, fmt, L"i", ntohs(a4->sin_port), NULL);
	    free(a4);
	}
    }
    sendadc(sk, 1, eoc, NULL);
}

#define ADC_CMDFN(name) static void name(struct fnetnode *fn, wchar_t *command, wchar_t *sender, int argc, wchar_t **argv)
#ifdef __GNUC__
#define UNUSED __attribute__ ((unused))
#else
#define UNUSED
#endif
#define ADC_CMDCOM \
	struct adchub *hub UNUSED = fn->data; \
	struct socket *sk UNUSED = hub->sk;

ADC_CMDFN(cmd_sup)
{
    ADC_CMDCOM;
    int i, o, f;
    
    for(i = 1; i < argc; i++) {
	if(wcslen(argv[i]) < 3)
	    continue;
	for(o = 0, f = 0; hub->sup[o]; o++) {
	    if(!wcscmp(argv[i] + 2, hub->sup[o])) {
		f = 1;
		break;
	    }
	}
	if(!wcsncmp(argv[i], L"AD", 2)) {
	    if(f)
		continue;
	    hub->sup = srealloc(hub->sup, sizeof(*(hub->sup)) * (o + 1));
	    hub->sup[o] = swcsdup(argv[i] + 2);
	} else if(!wcsncmp(argv[i], L"RM", 2)) {
	    if(!f)
		continue;
	    free(hub->sup[o]);
	    memmove(hub->sup[o], hub->sup[o + 1], parrlen(hub->sup) - o);
	}
    }
}

ADC_CMDFN(cmd_sid)
{
    ADC_CMDCOM;
    
    if(hub->sid != NULL)
	free(hub->sid);
    hub->sid = swcsdup(argv[1]);
    if(hub->state == ADC_PROTOCOL) {
	hub->state = ADC_IDENTIFY;
	sendinf(fn);
    }
}

ADC_CMDFN(cmd_inf)
{
    ADC_CMDCOM;
    wchar_t *p;
    
    if(sender == NULL) {
	if((p = findkv(argv, L"NI")) != NULL)
	    fnetsetname(fn, p);
    }
}

static struct command hubcmds[] = {
    {L"SUP", 1, 0, 0, cmd_sup},
    {L"SID", 2, 0, 0, cmd_sid},
    {L"INF", 1, 0, 0, cmd_inf},
    {NULL, 0, 0, 0, NULL}
};

static void dispatch(struct qcmd *qcmd, struct fnetnode *fn)
{
    struct command *cmd;
    int argc;
    wchar_t *cmdnm, *sender, **argv;
    
    if((argc = parrlen(argv = qcmd->args)) < 1)
	return;
    cmdnm = *(argv++);
    argc--;
    if(wcslen(cmdnm) < 2)
	return;
    sender = NULL;
    if((*cmdnm == L'B') || (*cmdnm == L'F')) {
	if(argc < 1)
	    return;
	sender = *(argv++);
	argc--;
    } else if((*cmdnm == L'D') || (*cmdnm == L'E')) {
	if(argc < 2)
	    return;
	sender = *argv;
	argv += 2;
	argc -= 2;
    }
    for(cmd = hubcmds; cmd->func != NULL; cmd++) {
	if(!wcscmp(cmd->name, qcmd->args[0] + 1)) {
	    if(argc < cmd->minargs)
		return;
	    cmd->func(fn, cmdnm, sender, argc, argv);
	    return;
	}
    }
    flog(LOG_DEBUG, "unknown adc command: %ls", qcmd->args[0]);
}

static void peeraccept(struct socket *sk, struct socket *newsk, void *uudata)
{
}

static void udpread(struct socket *sk, void *uudata)
{
}

static void hubread(struct socket *sk, struct fnetnode *fn)
{
    int ret;
    struct adchub *hub;
    char *newbuf, *p1, *p2;
    wchar_t *p;
    size_t datalen, cblen;
    
    hub = fn->data;
    if((newbuf = sockgetinbuf(sk, &datalen)) == NULL)
	return;
    if(hub->inbufdata > 1024)
	hub->inbufdata = 0;
    bufcat(hub->inbuf, newbuf, datalen);
    free(newbuf);
    /* Memory eating protection */
    if(hub->cbdata > 65536)
	hub->cbdata = 0;
    while(hub->inbufdata > 0) {
	if(hub->cbdata == hub->cbsize)
	    sizebuf2(hub->cb, hub->cbdata + datalen, 1);
	p1 = hub->inbuf;
	p2 = (char *)(hub->cb + hub->cbdata);
	cblen = sizeof(*(hub->cb)) * (hub->cbsize - hub->cbdata);
	ret = iconv(hub->ich, &p1, &hub->inbufdata, &p2, &cblen);
	memmove(hub->inbuf, p1, hub->inbufdata);
	if(((p2 - ((char *)hub->cb)) % sizeof(*hub->cb)) != 0) {
	    flog(LOG_CRIT, "Spotted a dismembered wchar_t!");
	    abort();
	}
	hub->cbdata = hub->cbsize - (cblen / sizeof(*(hub->cb)));
	if(ret < 0) {
	    if(errno == EILSEQ) {
		flog(LOG_DEBUG, "adc fnetnode %i sent illegal utf-8 sequence", fn->id);
		killfnetnode(fn);
		return;
	    } else if(errno == EINVAL) {
		break;
	    } else if(errno == E2BIG) {
		/* continue; */
	    } else {
		flog(LOG_WARNING, "bug? iconv returned unexpected error: %s", strerror(errno));
		return;
	    }
	}
    }
    while((p = wmemchr(hub->cb, L'\n', hub->cbdata)) != NULL) {
	*(p++) = L'\0';
	newqcmd(&hub->queue, parseadc(hub->cb));
	memmove(hub->cb, p, (hub->cbdata -= (p - hub->cb)) * sizeof(*(hub->cb)));
    }
}

static void huberr(struct socket *sk, int err, struct fnetnode *fn)
{
    killfnetnode(fn);
}

static void hubconnect(struct fnetnode *fn, struct socket *sk)
{
    struct adchub *hub;
    
    sk->readcb = (void (*)(struct socket *, void *))hubread;
    sk->errcb = (void (*)(struct socket *, int, void *))huberr;
    sk->data = fn;
    
    hub = smalloc(sizeof(*hub));
    memset(hub, 0, sizeof(*hub));
    getsock(hub->sk = sk);
    if((hub->ich = iconv_open("wchar_t", "utf-8")) == (iconv_t)-1) {
	flog(LOG_CRIT, "iconv cannot handle UTF-8: %s", strerror(errno));
	killfnetnode(fn);
	return;
    }
    fn->data = hub;
    sendadc(sk, 0, L"HSUP", L"ADBASE", L"ADTIGR", eoc, NULL);
}

static void hubdestroy(struct fnetnode *fn)
{
    struct adchub *hub;
    
    hub = fn->data;
    iconv_close(hub->ich);
    if(hub->inbuf != NULL)
	free(hub->inbuf);
    if(hub->sup != NULL)
	freeparr(hub->sup);
    free(hub);
}

static void hubkill(struct fnetnode *fn)
{
    struct adchub *hub;
    
    hub = fn->data;
    hub->sk->close = 1;
}

static int hubsetnick(struct fnetnode *fn, wchar_t *newnick)
{
    return(0);
}

static int hubreqconn(struct fnetpeer *peer)
{
    return(0);
}

static struct fnet adcnet_store = {
    .connect = hubconnect,
    .destroy = hubdestroy,
    .kill = hubkill,
    .setnick = hubsetnick,
    .reqconn = hubreqconn,
    .name = L"adc"
};

static struct fnet *adcnet = &adcnet_store;

static int run(void)
{
    int ret;
    struct fnetnode *fn, *nextfn;
    struct adchub *hub;
    struct qcmd *qcmd;
    
    ret = 0;
    for(fn = fnetnodes; fn != NULL; fn = nextfn) {
	nextfn = fn->next;
	if(fn->fnet != adcnet)
	    continue;
	if((hub = fn->data) == NULL)
	    continue;
	if((qcmd = ulqcmd(&hub->queue)) != NULL) {
	    if((hub->sk != NULL) && (hub->sk->state == SOCK_EST))
		dispatch(qcmd, fn);
	    freeqcmd(qcmd);
	    ret = 1;
	    break;
	}
    }
    return(ret);
}

static void preinit(int hup)
{
    if(hup)
	return;
    regfnet(adcnet);
}

static void makepid(char *idbuf)
{
    int i;
    int fd, ret;
    
    i = 0;
    if((fd = open("/dev/urandom", O_RDONLY)) >= 0) {
	for(i = 0; i < 24; i += ret) {
	    if((ret = read(fd, idbuf + i, 24 - i)) <= 0) {
		flog(LOG_WARNING, "could not read random data from /dev/urandom for ADC PID: %s", (errno == 0)?"EOF":strerror(errno));
		break;
	    }
	}
	close(fd);
    } else {
	flog(LOG_WARNING, "could not open /dev/urandom: %s", strerror(errno));
    }
    if(i != 24) {
	for(i = 0; i < sizeof(idbuf); i++)
	    idbuf[i] = rand() % 256;
    }
}

static int updateudpport(struct configvar *var, void *uudata)
{
    struct sockaddr_in addr;
    struct socket *newsock;
    
    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_port = htons(var->val.num);
    if((newsock = netcsdgram((struct sockaddr *)&addr, sizeof(addr))) == NULL)
    {
	flog(LOG_WARNING, "could not create new DC UDP socket, reverting to old: %s", strerror(errno));
	return(0);
    }
    newsock->readcb = udpread;
    if(udpsock != NULL)
	putsock(udpsock);
    udpsock = newsock;
    return(0);
}

static int updatetcpport(struct configvar *var, void *uudata)
{
    struct sockaddr_in addr;
    struct socket *newsock;
    
    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_port = htons(var->val.num);
    if((newsock = netcslisten(SOCK_STREAM, (struct sockaddr *)&addr, sizeof(addr), peeraccept, NULL)) == NULL)
	flog(LOG_INFO, "could not listen to a remote address, going into passive mode");
    if(tcpsock != NULL)
	putsock(tcpsock);
    tcpsock = newsock;
    return(0);
}

static int init(int hup)
{
    char idbuf[24], *id32;
    struct tigerhash th;
    struct sockaddr_in addr;
    
    if(!hup) {
	eoc = swcsdup(L"");
	ns = swcsdup(L"");
	fmt = swcsdup(L"");
	
	if((privid = fetchvar("adc.pid", NULL)) == NULL) {
	    makepid(idbuf);
	    id32 = base32encode(idbuf, sizeof(idbuf));
	    id32[39] = 0;
	    privid = icmbstowcs(id32, "us-ascii");
	    free(id32);
	    storevar("adc.pid", privid, sizeof(*privid) * (wcslen(privid) + 1));
	}
	
	id32 = base32decode(icswcstombs(privid, "us-ascii", NULL), NULL);
	inittiger(&th);
	dotiger(&th, id32, 24);
	synctiger(&th);
	free(id32);
	restiger(&th, idbuf);
	id32 = base32encode(idbuf, sizeof(idbuf));
	id32[39] = 0;
	cid = icmbstowcs(id32, "us-ascii");
	free(id32);
	
	memset(&addr, 0, sizeof(addr));
	addr.sin_family = AF_INET;
	addr.sin_port = htons(confgetint("adc", "udpport"));
	if((udpsock = netcsdgram((struct sockaddr *)&addr, sizeof(addr))) == NULL) {
	    flog(LOG_CRIT, "could not create ADC UDP socket: %s", strerror(errno));
	    return(1);
	}
	udpsock->readcb = udpread;
	addr.sin_port = htons(confgetint("adc", "tcpport"));
	if((tcpsock = netcslisten(SOCK_STREAM, (struct sockaddr *)&addr, sizeof(addr), peeraccept, NULL)) == NULL) {
	    flog(LOG_CRIT, "could not create ADC TCP socket: %s", strerror(errno));
	    return(1);
	}
	CBREG(confgetvar("adc", "udpport"), conf_update, updateudpport, NULL, NULL);
	CBREG(confgetvar("adc", "tcpport"), conf_update, updatetcpport, NULL, NULL);
	CBREG(confgetvar("net", "mode"), conf_update, updatetcpport, NULL, NULL);
    }
    return(0);
}

static void terminate(void)
{
    
}

static struct configvar myvars[] = {
    /** Specifies a specific UDP port to use for ADC search
     * results. If left unspecified, a port is allocated
     * dynamically. Useful for NAT routers (see also the
     * net.visibleipv4 address for those cases). */
    {CONF_VAR_INT, "udpport", {.num = 0}},
    /** Specifies a specific TCP port to use for ADC peer
     * connections. If left unspecified, a port is allocated
     * dynamically. Useful for NAT routers (see also the
     * net.visibleipv4 address for those cases). */
    {CONF_VAR_INT, "tcpport", {.num = 0}},
    {CONF_VAR_END}
};

static struct module me = {
    .conf = {
	.vars = myvars
    },
    .preinit = preinit,
    .init = init,
    .run = run,
    .terminate = terminate,
    .name = "adc"
};

MODULE(me)
Commit	Line	Data
58e83d6a	1	/*
58e83d6a	2	* Dolda Connect - Modular multiuser Direct Connect-style client
302a2600	3	* Copyright (C) 2004 Fredrik Tolf <fredrik@dolda2000.com>
58e83d6a	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation; either version 2 of the License, or
	8	* (at your option) any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	18	*/
	19	#include <stdlib.h>
	20	#include <stdio.h>
	21	#include <unistd.h>
6adc02a2	22	#include <fcntl.h>
58e83d6a	23	#include <stdarg.h>
	24	#include <string.h>
	25	#include <netinet/in.h>
	26	#include <arpa/inet.h>
	27	#include <wctype.h>
	28	#include <iconv.h>
	29	#include <errno.h>
	30
	31	#ifdef HAVE_CONFIG_H
	32	#include <config.h>
	33	#endif
	34	#include "filenet.h"
	35	#include "log.h"
	36	#include "module.h"
	37	#include "utils.h"
	38	#include "client.h"
	39	#include "transfer.h"
	40	#include "sysevents.h"
	41	#include "net.h"
24a794c2	42	#include <tiger.h>
58e83d6a	43
	44	/* Protocol states */
	45	#define ADC_PROTOCOL 0
	46	#define ADC_IDENTIFY 1
	47	#define ADC_VERIFY 2
	48	#define ADC_NORMAL 3
	49	#define ADC_DATA 4
	50
	51	struct command {
	52	wchar_t *name;
e2282058	53	int minargs, needsid, needsender;
58e83d6a	54	void (func)(struct fnetnode fn, wchar_t command, wchar_t sender, int argc, wchar_t **argv);
	55	};
	56
	57	struct qcmd {
	58	struct qcmd *next;
	59	wchar_t **args;
	60	};
	61
ed63a7f8 FT	62	struct qcmdqueue {
	63	struct qcmd f, l;
	64	int size;
	65	};
	66
58e83d6a	67	struct adchub {
ffa81d5f	68	struct socket *sk;
58e83d6a	69	char *inbuf;
	70	size_t inbufdata, inbufsize;
	71	wchar_t *sid;
	72	wchar_t *cb;
	73	size_t cbdata, cbsize;
	74	wchar_t **sup;
	75	iconv_t ich;
	76	int state;
24a794c2	77	struct wcspair *hubinf;
ed63a7f8	78	struct qcmdqueue queue;
58e83d6a	79	};
58e83d6a	80
e2282058	81	static wchar_t eoc, ns, *fmt;
58e83d6a	82	/* I've never understood why both of these are necessary, but... */
58e83d6a	83	static wchar_t privid, cid;
e2282058	84	struct socket udpsock, tcpsock;
58e83d6a	85
	86	static wchar_t *parseadc(wchar_t cmdline)
	87	{
	88	wchar_t **ret;
	89	size_t retsize, retdata;
	90	wchar_t p, p2, *ep;
	91	wchar_t r;
	92	ssize_t len;
	93
	94	ret = NULL;
	95	retsize = retdata = 0;
	96	p = cmdline;
	97	do {
	98	if((p2 = wcschr(p, L' ')) != NULL)
	99	*(p2++) = L'\0';
	100	len = wcslen(p);
	101	for(ep = p; len > 0; ep++, len--) {
	102	if(*ep == L'\\') {
	103	if(ep[1] == L's') {
	104	r = L' ';
	105	} else if(ep[1] == L'n') {
	106	r = L'\n';
	107	} else if(ep[1] == L'\\') {
	108	r = L'\\';
	109	} else {
	110	memmove(ep, ep + 2, (len -= 2) * sizeof(*ep));
	111	ep--;
	112	continue;
	113	}
	114	memmove(ep, ep + 1, --len * sizeof(*ep));
	115	*ep = r;
	116	}
	117	}
	118	*ep = L'\0';
	119	addtobuf(ret, swcsdup(p));
	120	p = p2;
	121	} while(p2 != NULL);
	122	addtobuf(ret, NULL);
	123	return(ret);
	124	}
	125
	126	static void sendeoc(struct socket *sk)
	127	{
	128	sockqueue(sk, "\n", 1);
	129	}
	130
	131	static void sendadc1(struct socket sk, int sep, wchar_t arg)
	132	{
	133	char *mbsbuf;
	134	wchar_t *buf;
	135	size_t bufsize, bufdata;
	136
	137	buf = NULL;
	138	bufsize = bufdata = 0;
	139	if(sep)
	140	addtobuf(buf, L' ');
	141	for(; *arg != L'\0'; arg++) {
	142	if(*arg == L' ')
	143	bufcat(buf, L"\\s", 2);
	144	else if(*arg == L'\n')
	145	bufcat(buf, L"\\n", 2);
	146	else if(*arg == L'\\')
	147	bufcat(buf, L"\\\\", 2);
	148	else
149	addtobuf(buf, *arg);
150	}
151	addtobuf(buf, L'\0');
152	mbsbuf = icwcstombs(buf, "utf-8");
153	sockqueue(sk, mbsbuf, strlen(mbsbuf));
154	free(mbsbuf);
155	}
156
157	static void sendadc(struct socket *sk, int sep, ...)
158	{
e2282058	159	int i;
58e83d6a	160	va_list args;
58e83d6a	161	wchar_t *arg;
e2282058	162	wchar_t type, buf;
58e83d6a	163
	164	va_start(args, sep);
	165	for(i = 0; (arg = va_arg(args, wchar_t *)) != NULL; i++) {
e2282058	166	if(arg == eoc) {
58e83d6a	167	sendeoc(sk);
e2282058 FT	168	} else if(arg == ns) {
	169	sep = 0;
	170	} else if(arg == fmt) {
	171	type = va_arg(args, wchar_t *);
	172	if(!wcscmp(type, L"i")) {
	173	buf = swprintf2(L"%i", va_arg(args, int));
	174	} else if(!wcscmp(type, L"mi")) {
	175	buf = swprintf2(L"%ji", va_arg(args, intmax_t));
	176	}
	177	sendadc1(sk, sep, buf);
	178	free(buf);
	179	sep = 1;
	180	} else {
	181	sendadc1(sk, sep, arg);
	182	sep = 1;
	183	}
58e83d6a	184	}
	185	va_end(args);
	186	}
	187
e2282058 FT	188	static wchar_t findkv(wchar_t argv, wchar_t name)
	189	{
	190	while(*argv != NULL) {
	191	if(!wcsncmp(*argv, name, 2))
	192	return((*argv) + 2);
	193	}
	194	return(NULL);
	195	}
	196
ed63a7f8	197	static struct qcmd newqcmd(struct qcmdqueue queue, wchar_t **args)
58e83d6a	198	{
	199	struct qcmd *new;
	200
58e83d6a	201	new = smalloc(sizeof(*new));
	202	new->next = NULL;
	203	new->args = args;
ed63a7f8 FT	204	if(queue->l == NULL)
	205	queue->f = new;
	206	else
	207	queue->l->next = new;
	208	queue->l = new;
	209	queue->size++;
58e83d6a	210	return(new);
	211	}
	212
ed63a7f8	213	static struct qcmd ulqcmd(struct qcmdqueue queue)
58e83d6a	214	{
	215	struct qcmd *ret;
	216
ed63a7f8	217	if((ret = queue->f) == NULL)
58e83d6a	218	return(NULL);
ed63a7f8 FT	219	if((queue->f = ret->next) == NULL)
	220	queue->l = NULL;
	221	queue->size--;
58e83d6a	222	return(ret);
	223	}
	224
	225	static void freeqcmd(struct qcmd *qcmd)
	226	{
	227	freeparr(qcmd->args);
	228	free(qcmd);
	229	}
	230
e2282058 FT	231	static void sendinf(struct fnetnode *fn)
	232	{
	233	struct adchub *hub = fn->data;
	234	struct socket *sk = hub->sk;
	235	struct sockaddr_in *a4;
	236	socklen_t alen;
	237
	238	sendadc(sk, 0, L"BINF", hub->sid, NULL);
	239	sendadc(sk, 1, L"PD", ns, privid, L"ID", ns, cid, NULL);
	240	sendadc(sk, 1, L"VEDolda ", ns, icsmbstowcs(VERSION, "us-ascii", NULL), NULL);
	241	sendadc(sk, 1, L"NI", ns, fn->mynick, NULL);
	242	sendadc(sk, 1, L"SS", ns, fmt, L"mi", (intmax_t)sharesize, L"SF", ns, fmt, L"i", sharedfiles, NULL);
	243	if(sk->family == AF_INET)
	244	sendadc(sk, 1, L"I40.0.0.0", NULL);
	245	else if(sk->family == AF_INET6)
	246	sendadc(sk, 1, L"I6::", NULL);
	247	sendadc(sk, 1, L"SL", ns, fmt, L"i", confgetint("transfer", "slot"), NULL);
	248	if(tcpsock != NULL) {
	249	if((sk->family == AF_INET) && !sockgetremotename(udpsock, (struct sockaddr **)&a4, &alen)) {
	250	sendadc(sk, 1, L"U4", ns, fmt, L"i", ntohs(a4->sin_port), NULL);
	251	free(a4);
	252	}
	253	}
	254	sendadc(sk, 1, eoc, NULL);
	255	}
	256
58e83d6a	257	#define ADC_CMDFN(name) static void name(struct fnetnode fn, wchar_t command, wchar_t sender, int argc, wchar_t *argv)
0d6c5363	258	#ifdef __GNUC__
9db779f4	259	#define UNUSED __attribute__ ((unused))
0d6c5363	260	#else
9db779f4	261	#define UNUSED
0d6c5363	262	#endif
9db779f4	263	#define ADC_CMDCOM \
ffa81d5f FT	264	struct adchub *hub UNUSED = fn->data; \
ffa81d5f FT	265	struct socket *sk UNUSED = hub->sk;
58e83d6a	266
	267	ADC_CMDFN(cmd_sup)
	268	{
	269	ADC_CMDCOM;
	270	int i, o, f;
	271
	272	for(i = 1; i < argc; i++) {
	273	if(wcslen(argv[i]) < 3)
	274	continue;
	275	for(o = 0, f = 0; hub->sup[o]; o++) {
	276	if(!wcscmp(argv[i] + 2, hub->sup[o])) {
	277	f = 1;
	278	break;
	279	}
	280	}
	281	if(!wcsncmp(argv[i], L"AD", 2)) {
	282	if(f)
	283	continue;
	284	hub->sup = srealloc(hub->sup, sizeof((hub->sup)) (o + 1));
	285	hub->sup[o] = swcsdup(argv[i] + 2);
	286	} else if(!wcsncmp(argv[i], L"RM", 2)) {
	287	if(!f)
	288	continue;
24a794c2	289	free(hub->sup[o]);
58e83d6a	290	memmove(hub->sup[o], hub->sup[o + 1], parrlen(hub->sup) - o);
	291	}
	292	}
	293	}
	294
	295	ADC_CMDFN(cmd_sid)
	296	{
	297	ADC_CMDCOM;
	298
	299	if(hub->sid != NULL)
	300	free(hub->sid);
	301	hub->sid = swcsdup(argv[1]);
	302	if(hub->state == ADC_PROTOCOL) {
	303	hub->state = ADC_IDENTIFY;
e2282058	304	sendinf(fn);
58e83d6a	305	}
	306	}
	307
24a794c2	308	ADC_CMDFN(cmd_inf)
	309	{
	310	ADC_CMDCOM;
e2282058	311	wchar_t *p;
24a794c2	312
24a794c2	313	if(sender == NULL) {
e2282058 FT	314	if((p = findkv(argv, L"NI")) != NULL)
e2282058 FT	315	fnetsetname(fn, p);
24a794c2	316	}
	317	}
	318
58e83d6a	319	static struct command hubcmds[] = {
e2282058 FT	320	{L"SUP", 1, 0, 0, cmd_sup},
	321	{L"SID", 2, 0, 0, cmd_sid},
	322	{L"INF", 1, 0, 0, cmd_inf},
	323	{NULL, 0, 0, 0, NULL}
58e83d6a	324	};
	325
	326	static void dispatch(struct qcmd qcmd, struct fnetnode fn)
	327	{
	328	struct command *cmd;
	329	int argc;
	330	wchar_t cmdnm, sender, **argv;
	331
	332	if((argc = parrlen(argv = qcmd->args)) < 1)
	333	return;
	334	cmdnm = *(argv++);
	335	argc--;
	336	if(wcslen(cmdnm) < 2)
	337	return;
	338	sender = NULL;
	339	if((cmdnm == L'B') \|\| (cmdnm == L'F')) {
	340	if(argc < 1)
	341	return;
	342	sender = *(argv++);
	343	argc--;
	344	} else if((cmdnm == L'D') \|\| (cmdnm == L'E')) {
	345	if(argc < 2)
	346	return;
	347	sender = *argv;
	348	argv += 2;
	349	argc -= 2;
	350	}
	351	for(cmd = hubcmds; cmd->func != NULL; cmd++) {
	352	if(!wcscmp(cmd->name, qcmd->args[0] + 1)) {
	353	if(argc < cmd->minargs)
	354	return;
6adc02a2	355	cmd->func(fn, cmdnm, sender, argc, argv);
58e83d6a	356	return;
	357	}
	358	}
	359	flog(LOG_DEBUG, "unknown adc command: %ls", qcmd->args[0]);
	360	}
	361
e2282058 FT	362	static void peeraccept(struct socket sk, struct socket newsk, void *uudata)
	363	{
	364	}
	365
	366	static void udpread(struct socket sk, void uudata)
	367	{
	368	}
	369
cab0b442	370	static void hubread(struct socket sk, struct fnetnode fn)
58e83d6a	371	{
	372	int ret;
	373	struct adchub *hub;
	374	char newbuf, p1, *p2;
	375	wchar_t *p;
	376	size_t datalen, cblen;
	377
	378	hub = fn->data;
	379	if((newbuf = sockgetinbuf(sk, &datalen)) == NULL)
cab0b442	380	return;
58e83d6a	381	if(hub->inbufdata > 1024)
	382	hub->inbufdata = 0;
	383	bufcat(hub->inbuf, newbuf, datalen);
	384	free(newbuf);
	385	/* Memory eating protection */
	386	if(hub->cbdata > 65536)
	387	hub->cbdata = 0;
	388	while(hub->inbufdata > 0) {
	389	if(hub->cbdata == hub->cbsize)
	390	sizebuf2(hub->cb, hub->cbdata + datalen, 1);
	391	p1 = hub->inbuf;
	392	p2 = (char *)(hub->cb + hub->cbdata);
	393	cblen = sizeof((hub->cb)) (hub->cbsize - hub->cbdata);
	394	ret = iconv(hub->ich, &p1, &hub->inbufdata, &p2, &cblen);
	395	memmove(hub->inbuf, p1, hub->inbufdata);
	396	if(((p2 - ((char )hub->cb)) % sizeof(hub->cb)) != 0) {
	397	flog(LOG_CRIT, "Spotted a dismembered wchar_t!");
	398	abort();
	399	}
	400	hub->cbdata = hub->cbsize - (cblen / sizeof(*(hub->cb)));
	401	if(ret < 0) {
	402	if(errno == EILSEQ) {
	403	flog(LOG_DEBUG, "adc fnetnode %i sent illegal utf-8 sequence", fn->id);
	404	killfnetnode(fn);
cab0b442	405	return;
58e83d6a	406	} else if(errno == EINVAL) {
	407	break;
	408	} else if(errno == E2BIG) {
	409	/* continue; */
	410	} else {
	411	flog(LOG_WARNING, "bug? iconv returned unexpected error: %s", strerror(errno));
cab0b442	412	return;
58e83d6a	413	}
	414	}
	415	}
	416	while((p = wmemchr(hub->cb, L'\n', hub->cbdata)) != NULL) {
	417	*(p++) = L'\0';
	418	newqcmd(&hub->queue, parseadc(hub->cb));
	419	memmove(hub->cb, p, (hub->cbdata -= (p - hub->cb)) * sizeof(*(hub->cb)));
	420	}
	421	}
	422
cab0b442	423	static void huberr(struct socket sk, int err, struct fnetnode fn)
58e83d6a	424	{
	425	killfnetnode(fn);
	426	}
	427
ffa81d5f	428	static void hubconnect(struct fnetnode fn, struct socket sk)
58e83d6a	429	{
	430	struct adchub *hub;
	431
ffa81d5f FT	432	sk->readcb = (void ()(struct socket , void *))hubread;
	433	sk->errcb = (void ()(struct socket , int, void *))huberr;
	434	sk->data = fn;
58e83d6a	435
	436	hub = smalloc(sizeof(*hub));
	437	memset(hub, 0, sizeof(*hub));
70d8f2f1	438	getsock(hub->sk = sk);
58e83d6a	439	if((hub->ich = iconv_open("wchar_t", "utf-8")) == (iconv_t)-1) {
	440	flog(LOG_CRIT, "iconv cannot handle UTF-8: %s", strerror(errno));
	441	killfnetnode(fn);
	442	return;
	443	}
	444	fn->data = hub;
6adc02a2	445	sendadc(sk, 0, L"HSUP", L"ADBASE", L"ADTIGR", eoc, NULL);
58e83d6a	446	}
	447
	448	static void hubdestroy(struct fnetnode *fn)
	449	{
	450	struct adchub *hub;
	451
ffa81d5f	452	hub = fn->data;
58e83d6a	453	iconv_close(hub->ich);
	454	if(hub->inbuf != NULL)
	455	free(hub->inbuf);
	456	if(hub->sup != NULL)
	457	freeparr(hub->sup);
	458	free(hub);
	459	}
	460
ffa81d5f FT	461	static void hubkill(struct fnetnode *fn)
	462	{
	463	struct adchub *hub;
	464
	465	hub = fn->data;
	466	hub->sk->close = 1;
	467	}
	468
58e83d6a	469	static int hubsetnick(struct fnetnode fn, wchar_t newnick)
	470	{
	471	return(0);
	472	}
	473
	474	static int hubreqconn(struct fnetpeer *peer)
	475	{
	476	return(0);
	477	}
	478
3ad44ea7	479	static struct fnet adcnet_store = {
58e83d6a	480	.connect = hubconnect,
58e83d6a	481	.destroy = hubdestroy,
ffa81d5f	482	.kill = hubkill,
58e83d6a	483	.setnick = hubsetnick,
	484	.reqconn = hubreqconn,
	485	.name = L"adc"
	486	};
	487
3ad44ea7	488	static struct fnet *adcnet = &adcnet_store;
3ad44ea7	489
58e83d6a	490	static int run(void)
	491	{
	492	int ret;
	493	struct fnetnode fn, nextfn;
	494	struct adchub *hub;
	495	struct qcmd *qcmd;
	496
	497	ret = 0;
	498	for(fn = fnetnodes; fn != NULL; fn = nextfn) {
	499	nextfn = fn->next;
3ad44ea7	500	if(fn->fnet != adcnet)
58e83d6a	501	continue;
	502	if((hub = fn->data) == NULL)
	503	continue;
	504	if((qcmd = ulqcmd(&hub->queue)) != NULL) {
ffa81d5f	505	if((hub->sk != NULL) && (hub->sk->state == SOCK_EST))
58e83d6a	506	dispatch(qcmd, fn);
	507	freeqcmd(qcmd);
	508	ret = 1;
	509	break;
	510	}
	511	}
	512	return(ret);
	513	}
	514
	515	static void preinit(int hup)
	516	{
	517	if(hup)
	518	return;
3ad44ea7	519	regfnet(adcnet);
58e83d6a	520	}
58e83d6a	521
6adc02a2	522	static void makepid(char *idbuf)
58e83d6a	523	{
58e83d6a	524	int i;
6adc02a2 FT	525	int fd, ret;
	526
	527	i = 0;
	528	if((fd = open("/dev/urandom", O_RDONLY)) >= 0) {
	529	for(i = 0; i < 24; i += ret) {
	530	if((ret = read(fd, idbuf + i, 24 - i)) <= 0) {
	531	flog(LOG_WARNING, "could not read random data from /dev/urandom for ADC PID: %s", (errno == 0)?"EOF":strerror(errno));
	532	break;
	533	}
	534	}
	535	close(fd);
	536	} else {
	537	flog(LOG_WARNING, "could not open /dev/urandom: %s", strerror(errno));
	538	}
	539	if(i != 24) {
	540	for(i = 0; i < sizeof(idbuf); i++)
	541	idbuf[i] = rand() % 256;
	542	}
	543	}
	544
e2282058 FT	545	static int updateudpport(struct configvar var, void uudata)
	546	{
	547	struct sockaddr_in addr;
	548	struct socket *newsock;
	549
	550	memset(&addr, 0, sizeof(addr));
	551	addr.sin_family = AF_INET;
	552	addr.sin_port = htons(var->val.num);
	553	if((newsock = netcsdgram((struct sockaddr *)&addr, sizeof(addr))) == NULL)
	554	{
	555	flog(LOG_WARNING, "could not create new DC UDP socket, reverting to old: %s", strerror(errno));
	556	return(0);
	557	}
	558	newsock->readcb = udpread;
	559	if(udpsock != NULL)
	560	putsock(udpsock);
	561	udpsock = newsock;
	562	return(0);
	563	}
	564
	565	static int updatetcpport(struct configvar var, void uudata)
	566	{
	567	struct sockaddr_in addr;
	568	struct socket *newsock;
	569
	570	memset(&addr, 0, sizeof(addr));
	571	addr.sin_family = AF_INET;
	572	addr.sin_port = htons(var->val.num);
	573	if((newsock = netcslisten(SOCK_STREAM, (struct sockaddr *)&addr, sizeof(addr), peeraccept, NULL)) == NULL)
	574	flog(LOG_INFO, "could not listen to a remote address, going into passive mode");
	575	if(tcpsock != NULL)
	576	putsock(tcpsock);
	577	tcpsock = newsock;
	578	return(0);
	579	}
	580
6adc02a2 FT	581	static int init(int hup)
6adc02a2 FT	582	{
58e83d6a	583	char idbuf[24], *id32;
58e83d6a	584	struct tigerhash th;
e2282058	585	struct sockaddr_in addr;
58e83d6a	586
	587	if(!hup) {
	588	eoc = swcsdup(L"");
e2282058 FT	589	ns = swcsdup(L"");
e2282058 FT	590	fmt = swcsdup(L"");
58e83d6a	591
58e83d6a	592	if((privid = fetchvar("adc.pid", NULL)) == NULL) {
6adc02a2	593	makepid(idbuf);
58e83d6a	594	id32 = base32encode(idbuf, sizeof(idbuf));
	595	id32[39] = 0;
	596	privid = icmbstowcs(id32, "us-ascii");
	597	free(id32);
	598	storevar("adc.pid", privid, sizeof(privid) (wcslen(privid) + 1));
	599	}
	600
	601	id32 = base32decode(icswcstombs(privid, "us-ascii", NULL), NULL);
	602	inittiger(&th);
	603	dotiger(&th, id32, 24);
	604	synctiger(&th);
	605	free(id32);
	606	restiger(&th, idbuf);
	607	id32 = base32encode(idbuf, sizeof(idbuf));
	608	id32[39] = 0;
	609	cid = icmbstowcs(id32, "us-ascii");
	610	free(id32);
e2282058 FT	611
	612	memset(&addr, 0, sizeof(addr));
	613	addr.sin_family = AF_INET;
	614	addr.sin_port = htons(confgetint("adc", "udpport"));
	615	if((udpsock = netcsdgram((struct sockaddr *)&addr, sizeof(addr))) == NULL) {
	616	flog(LOG_CRIT, "could not create ADC UDP socket: %s", strerror(errno));
	617	return(1);
	618	}
	619	udpsock->readcb = udpread;
	620	addr.sin_port = htons(confgetint("adc", "tcpport"));
	621	if((tcpsock = netcslisten(SOCK_STREAM, (struct sockaddr *)&addr, sizeof(addr), peeraccept, NULL)) == NULL) {
	622	flog(LOG_CRIT, "could not create ADC TCP socket: %s", strerror(errno));
	623	return(1);
	624	}
	625	CBREG(confgetvar("adc", "udpport"), conf_update, updateudpport, NULL, NULL);
	626	CBREG(confgetvar("adc", "tcpport"), conf_update, updatetcpport, NULL, NULL);
	627	CBREG(confgetvar("net", "mode"), conf_update, updatetcpport, NULL, NULL);
58e83d6a	628	}
	629	return(0);
	630	}
	631
	632	static void terminate(void)
	633	{
	634
	635	}
	636
	637	static struct configvar myvars[] = {
d9f89ef5	638	/** Specifies a specific UDP port to use for ADC search
	639	* results. If left unspecified, a port is allocated
	640	* dynamically. Useful for NAT routers (see also the
	641	* net.visibleipv4 address for those cases). */
58e83d6a	642	{CONF_VAR_INT, "udpport", {.num = 0}},
d9f89ef5	643	/** Specifies a specific TCP port to use for ADC peer
	644	* connections. If left unspecified, a port is allocated
	645	* dynamically. Useful for NAT routers (see also the
	646	* net.visibleipv4 address for those cases). */
58e83d6a	647	{CONF_VAR_INT, "tcpport", {.num = 0}},
	648	{CONF_VAR_END}
	649	};
	650
	651	static struct module me = {
	652	.conf = {
	653	.vars = myvars
	654	},
	655	.preinit = preinit,
	656	.init = init,
	657	.run = run,
	658	.terminate = terminate,
	659	.name = "adc"
	660	};
	661
	662	MODULE(me)