[ashd.git] / src / htparser.c

/*
    ashd - A Sane HTTP Daemon
    Copyright (C) 2008  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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <sys/socket.h>
#include <pwd.h>
#include <sys/signal.h>
#include <errno.h>

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <utils.h>
#include <mt.h>
#include <mtio.h>
#include <log.h>
#include <req.h>
#include <proc.h>
#include <bufio.h>

#include "htparser.h"

static int plex;
static char *pidfile = NULL;
static int daemonize, usesyslog;
struct mtbuf listeners;

static void trimx(struct hthead *req)
{
    int i;
    
    i = 0;
    while(i < req->noheaders) {
	if(!strncasecmp(req->headers[i][0], "x-ash-", 6)) {
	    free(req->headers[i][0]);
	    free(req->headers[i][1]);
	    free(req->headers[i]);
	    memmove(req->headers + i, req->headers + i + 1, sizeof(*req->headers) * (--req->noheaders - i));
	} else {
	    i++;
	}
    }
}

static struct hthead *parsereq(struct bufio *in)
{
    struct hthead *req;
    struct charbuf method, url, ver;
    int c;
    
    req = NULL;
    bufinit(method);
    bufinit(url);
    bufinit(ver);
    while(1) {
	c = biogetc(in);
	if(c == ' ') {
	    break;
	} else if((c == EOF) || (c < 32) || (c >= 128)) {
	    goto fail;
	} else {
	    bufadd(method, c);
	    if(method.d >= 128)
		goto fail;
	}
    }
    while(1) {
	c = biogetc(in);
	if(c == ' ') {
	    break;
	} else if((c == EOF) || (c < 32)) {
	    goto fail;
	} else {
	    bufadd(url, c);
	    if(url.d >= 65536)
		goto fail;
	}
    }
    while(1) {
	c = biogetc(in);
	if(c == 10) {
	    break;
	} else if(c == 13) {
	} else if((c == EOF) || (c < 32) || (c >= 128)) {
	    goto fail;
	} else {
	    bufadd(ver, c);
	    if(ver.d >= 128)
		goto fail;
	}
    }
    bufadd(method, 0);
    bufadd(url, 0);
    bufadd(ver, 0);
    req = mkreq(method.b, url.b, ver.b);
    if(parseheadersb(req, in))
	goto fail;
    trimx(req);
    goto out;
    
fail:
    if(req != NULL) {
	freehthead(req);
	req = NULL;
    }
out:
    buffree(method);
    buffree(url);
    buffree(ver);
    return(req);
}

static off_t passdata(struct bufio *in, struct bufio *out, off_t max)
{
    ssize_t read;
    off_t total;
    
    total = 0;
    while(!bioeof(in) && ((max < 0) || (total < max))) {
	if((read = biordata(in)) > 0) {
	    if(max >= 0)
		read = min(max - total, read);
	    if((read = biowritesome(out, in->rbuf.b + in->rh, read)) < 0)
		return(-1);
	    in->rh += read;
	    total += read;
	}
	if(biorspace(in) && ((max < 0) || (biordata(in) < max - total)) && (biofillsome(in) < 0))
	    return(-1);
    }
    return(total);
}

static int recvchunks(struct bufio *in, struct bufio *out)
{
    size_t read, chlen;
    int c, r;
    
    while(1) {
	chlen = 0;
	r = 0;
	while(1) {
	    c = biogetc(in);
	    if(c == 10) {
		if(!r)
		    return(-1);
		break;
	    } else if(c == 13) {
	    } else if((c >= '0') && (c <= '9')) {
		chlen = (chlen << 4) + (c - '0');
		r = 1;
	    } else if((c >= 'A') && (c <= 'F')) {
		chlen = (chlen << 4) + (c + 10 - 'A');
		r = 1;
	    } else if((c >= 'a') && (c <= 'f')) {
		chlen = (chlen << 4) + (c + 10 - 'a');
		r = 1;
	    } else {
		/* XXX: Technically, there may be chunk extensions to
		 * be read, but since that will likely never actually
		 * happen in practice, I can just as well add support
		 * for that if it actually does become relevant. */
		return(-1);
	    }
	}
	if(chlen == 0)
	    break;
	while(chlen > 0) {
	    if((read = biordata(in)) > 0) {
		if((read = biowritesome(out, in->rbuf.b + in->rh, min(read, chlen))) < 0)
		    return(-1);
		in->rh += read;
		chlen -= read;
	    }
	    if(biorspace(in) && (biordata(in) < chlen) && (biofillsome(in) <= 0))
		return(-1);
	}
	if((biogetc(in) != 13) || (biogetc(in) != 10))
	    return(-1);
    }
    /* XXX: Technically, there may be trailers to be read, but that's
     * just about as likely as chunk extensions. */
    if((biogetc(in) != 13) || (biogetc(in) != 10))
	return(-1);
    return(0);
}

static int passchunks(struct bufio *in, struct bufio *out)
{
    size_t read;
    
    while(!bioeof(in)) {
	if((read = biordata(in)) > 0) {
	    bioprintf(out, "%zx\r\n", read);
	    if(biowrite(out, in->rbuf.b + in->rh, read) != read)
		return(-1);
	    in->rh += read;
	    bioprintf(out, "\r\n");
	    if(bioflush(out) < 0)
		return(-1);
	}
	if(biorspace(in) && (biofillsome(in) < 0))
	    return(-1);
    }
    bioprintf(out, "0\r\n\r\n");
    return(0);
}

static int hasheader(struct hthead *head, char *name, char *val)
{
    char *hd;
    
    if((hd = getheader(head, name)) == NULL)
	return(0);
    return(!strcasecmp(hd, val));
}

static int canonreq(struct hthead *req)
{
    char *p, *p2, *r;
    int n;

    if(req->url[0] == '/') {
	replrest(req, req->url + 1);
	if((p = strchr(req->rest, '?')) != NULL)
	    *p = 0;
	return(1);
    }
    if((p = strstr(req->url, "://")) != NULL) {
	n = p - req->url;
	if(((n == 4) && !strncasecmp(req->url, "http", 4)) ||
	   ((n == 5) && !strncasecmp(req->url, "https", 5))) {
	    if(getheader(req, "host"))
		return(0);
	    p += 3;
	    if((p2 = strchr(p, '/')) == NULL) {
		headappheader(req, "Host", p);
		free(req->url);
		req->url = sstrdup("/");
	    } else {
		r = sstrdup(p2);
		*(p2++) = 0;
		headappheader(req, "Host", p);
		free(req->url);
		req->url = r;
	    }
	    replrest(req, req->url + 1);
	    if((p = strchr(req->rest, '?')) != NULL)
		*p = 0;
	    return(1);
	}
    }
    return(0);
}

static int http10keep(struct hthead *req, struct hthead *resp)
{
    int fc;
    
    fc = hasheader(resp, "connection", "close");
    headrmheader(resp, "connection");
    if(!fc && hasheader(req, "connection", "keep-alive")) {
	headappheader(resp, "Connection", "Keep-Alive");
	return(1);
    } else {
	return(0);
    }
}

static char *connid(void)
{
    static struct charbuf cur;
    int i;
    char *ret;
    
    for(i = 0; i < cur.d; i++) {
	if((++cur.b[i]) > 'Z')
	    cur.b[i] = 'A';
	else
	    goto done;
    }
    bufadd(cur, 'A');
done:
    ret = memcpy(smalloc(cur.d + 1), cur.b, cur.d);
    ret[cur.d] = 0;
    return(ret);
}

static void passduplex(struct bufio *a, int afd, struct bufio *b, int bfd)
{
    struct selected pfd[4], sel;
    struct bufio *sio;
    int n, ev;
    
    while(!bioeof(a) && !bioeof(b)) {
	biocopybuf(b, a);
	biocopybuf(a, b);
	n = 0;
	if(!a->eof) {
	    ev = 0;
	    if(biorspace(a))
		ev |= EV_READ;
	    if(biowdata(a))
		ev |= EV_WRITE;
	    if(ev)
		pfd[n++] = (struct selected){.fd = afd, .ev = ev};
	}
	if(!b->eof) {
	    ev = 0;
	    if(!b->eof && biorspace(b))
		ev |= EV_READ;
	    if(biowdata(b))
		ev |= EV_WRITE;
	    if(ev)
		pfd[n++] = (struct selected){.fd = bfd, .ev = ev};
	}
	sel = mblock(600, n, pfd);
	if(sel.fd == afd)
	    sio = a;
	else if(sel.fd == bfd)
	    sio = b;
	else
	    break;
	if((sel.ev & EV_READ) && (biofillsome(sio) < 0))
	    break;
	if((sel.ev & EV_WRITE) && (bioflushsome(sio) < 0))
	    break;
    }
}

void serve(struct bufio *in, int infd, struct conn *conn)
{
    int pfds[2];
    struct bufio *out, *dout;
    struct stdiofd *outi;
    struct hthead *req, *resp;
    char *hd, *id;
    off_t dlen;
    int keep, duplex;
    
    id = connid();
    out = NULL;
    req = resp = NULL;
    while(plex >= 0) {
	bioflush(in);
	if((req = parsereq(in)) == NULL)
	    break;
	if(!canonreq(req))
	    break;
	
	headappheader(req, "X-Ash-Connection-ID", id);
	if((conn->initreq != NULL) && conn->initreq(conn, req))
	    break;
	
	if((plex < 0) || block(plex, EV_WRITE, 60) <= 0)
	    break;
	if(socketpair(PF_UNIX, SOCK_STREAM, 0, pfds))
	    break;
	if(sendreq(plex, req, pfds[0]))
	    break;
	close(pfds[0]);
	out = mtbioopen(pfds[1], 1, 600, "r+", &outi);

	if(getheader(req, "content-type") != NULL) {
	    if((hd = getheader(req, "content-length")) != NULL) {
		dlen = atoo(hd);
		if(dlen > 0) {
		    if(passdata(in, out, dlen) != dlen)
			break;
		}
	    } else if(((hd = getheader(req, "transfer-encoding")) != NULL) && !strcasecmp(hd, "chunked")) {
		if(recvchunks(in, out))
		    break;
	    } else {
		/* Ignore rather than abort, to be kinder to broken clients. */
		headrmheader(req, "content-type");
	    }
	}
	if(bioflush(out))
	    break;
	/* Make sure to send EOF */
	shutdown(pfds[1], SHUT_WR);
	
	if((resp = parseresponseb(out)) == NULL)
	    break;
	replstr(&resp->ver, req->ver);
	
	if(!getheader(resp, "server"))
	    headappheader(resp, "Server", sprintf3("ashd/%s", VERSION));
	duplex = hasheader(resp, "x-ash-switch", "duplex");
	trimx(resp);

	if(duplex) {
	    if(outi->rights < 0)
		break;
	    writerespb(in, resp);
	    bioprintf(in, "\r\n");
	    dout = mtbioopen(outi->rights, 1, 600, "r+", NULL);
	    passduplex(in, infd, dout, outi->rights);
	    outi->rights = -1;
	    bioclose(dout);
	    break;
	} else if(!strcasecmp(req->ver, "HTTP/1.0")) {
	    if(!strcasecmp(req->method, "head")) {
		keep = http10keep(req, resp);
		writerespb(in, resp);
		bioprintf(in, "\r\n");
	    } else if((hd = getheader(resp, "content-length")) != NULL) {
		keep = http10keep(req, resp);
		dlen = atoo(hd);
		writerespb(in, resp);
		bioprintf(in, "\r\n");
		if(passdata(out, in, dlen) != dlen)
		    break;
	    } else {
		headrmheader(resp, "connection");
		writerespb(in, resp);
		bioprintf(in, "\r\n");
		passdata(out, in, -1);
		break;
	    }
	    if(!keep)
		break;
	} else if(!strcasecmp(req->ver, "HTTP/1.1")) {
	    if(!strcasecmp(req->method, "head")) {
		writerespb(in, resp);
		bioprintf(in, "\r\n");
	    } else if((hd = getheader(resp, "content-length")) != NULL) {
		writerespb(in, resp);
		bioprintf(in, "\r\n");
		dlen = atoo(hd);
		if(passdata(out, in, dlen) != dlen)
		    break;
	    } else if(!getheader(resp, "transfer-encoding")) {
		headappheader(resp, "Transfer-Encoding", "chunked");
		writerespb(in, resp);
		bioprintf(in, "\r\n");
		if(passchunks(out, in))
		    break;
	    } else {
		writerespb(in, resp);
		bioprintf(in, "\r\n");
		passdata(out, in, -1);
		break;
	    }
	    if(hasheader(req, "connection", "close") || hasheader(resp, "connection", "close"))
		break;
	} else {
	    break;
	}

	bioclose(out);
	out = NULL;
	freehthead(req);
	freehthead(resp);
	req = resp = NULL;
    }
    
    if(out != NULL)
	bioclose(out);
    if(req != NULL)
	freehthead(req);
    if(resp != NULL)
	freehthead(resp);
    bioclose(in);
    free(id);
}

static void plexwatch(struct muth *muth, va_list args)
{
    vavar(int, fd);
    char *buf;
    int i, s, ret;
    
    s = 0;
    while(1) {
	if(block(fd, EV_READ, 0) == 0)
	    break;
	buf = smalloc(65536);
	ret = recv(fd, buf, 65536, 0);
	if(ret < 0) {
	    flog(LOG_WARNING, "received error on rootplex read channel: %s", strerror(errno));
	    exit(1);
	} else if(ret == 0) {
	    s = 1;
	    free(buf);
	    break;
	}
	/* Maybe I'd like to implement some protocol in this direction
	 * some day... */
	free(buf);
    }
    shutdown(plex, SHUT_RDWR);
    for(i = 0; i < listeners.d; i++) {
	if(listeners.b[i] == muth)
	    bufdel(listeners, i);
    }
    if(s) {
	flog(LOG_INFO, "root handler exited, so shutting down listening...");
	while(listeners.d > 0)
	    resume(listeners.b[0], 0);
    }
}

static void initroot(void *uu)
{
    int fd;
    
    setsid();
    if(daemonize) {
	chdir("/");
	if((fd = open("/dev/null", O_RDWR)) >= 0) {
	    dup2(fd, 0);
	    dup2(fd, 1);
	    dup2(fd, 2);
	    close(fd);
	}
    }
    if(usesyslog)
	putenv("ASHD_USESYSLOG=1");
    else
	unsetenv("ASHD_USESYSLOG");
}

static void usage(FILE *out)
{
    fprintf(out, "usage: htparser [-hSf] [-u USER] [-r ROOT] [-p PIDFILE] PORTSPEC... -- ROOT [ARGS...]\n");
    fprintf(out, "\twhere PORTSPEC is HANDLER[:PAR[=VAL][(,PAR[=VAL])...]] (try HANDLER:help)\n");
    fprintf(out, "\tavailable handlers are `plain' and `ssl'.\n");
}

static void addport(char *spec)
{
    char *nm, *p, *p2, *n;
    struct charvbuf pars, vals;
    
    bufinit(pars);
    bufinit(vals);
    if((p = strchr(spec, ':')) == NULL) {
	nm = spec;
    } else {
	nm = spec;
	*(p++) = 0;
	do {
	    if((n = strchr(p, ',')) != NULL)
		*(n++) = 0;
	    if((p2 = strchr(p, '=')) != NULL)
		*(p2++) = 0;
	    if(!*p) {
		usage(stderr);
		exit(1);
	    }
	    bufadd(pars, p);
	    if(p2)
		bufadd(vals, p2);
	    else
		bufadd(vals, "");
	} while((p = n) != NULL);
    }
    
    /* XXX: It would be nice to decentralize this, but, meh... */
    if(!strcmp(nm, "plain")) {
	handleplain(pars.d, pars.b, vals.b);
#ifdef HAVE_GNUTLS
    } else if(!strcmp(nm, "ssl")) {
	handlegnussl(pars.d, pars.b, vals.b);
#endif
    } else {
	flog(LOG_ERR, "htparser: unknown port handler `%s'", nm);
	exit(1);
    }
    
    buffree(pars);
    buffree(vals);
}

static void sighandler(int sig)
{
    exitioloop(1);
}

int main(int argc, char **argv)
{
    int c, d;
    int i, s1;
    char *root;
    FILE *pidout;
    struct passwd *pwent;
    
    daemonize = usesyslog = 0;
    root = NULL;
    pwent = NULL;
    while((c = getopt(argc, argv, "+hSfu:r:p:")) >= 0) {
	switch(c) {
	case 'h':
	    usage(stdout);
	    exit(0);
	case 'f':
	    daemonize = 1;
	    break;
	case 'S':
	    usesyslog = 1;
	    break;
	case 'u':
	    if((pwent = getpwnam(optarg)) == NULL) {
		flog(LOG_ERR, "could not find user %s", optarg);
		exit(1);
	    }
	    break;
	case 'r':
	    root = optarg;
	    break;
	case 'p':
	    pidfile = optarg;
	    break;
	default:
	    usage(stderr);
	    exit(1);
	}
    }
    s1 = 0;
    for(i = optind; i < argc; i++) {
	if(!strcmp(argv[i], "--"))
	    break;
	s1 = 1;
	addport(argv[i]);
    }
    if(!s1 || (i == argc)) {
	usage(stderr);
	exit(1);
    }
    if((plex = stdmkchild(argv + ++i, initroot, NULL)) < 0) {
	flog(LOG_ERR, "could not spawn root multiplexer: %s", strerror(errno));
	return(1);
    }
    bufadd(listeners, mustart(plexwatch, plex));
    pidout = NULL;
    if(pidfile != NULL) {
	if((pidout = fopen(pidfile, "w")) == NULL) {
	    flog(LOG_ERR, "could not open %s for writing: %s", pidfile, strerror(errno));
	    return(1);
	}
    }
    if(usesyslog)
	opensyslog();
    if(root) {
	if(chdir(root) || chroot(root)) {
	    flog(LOG_ERR, "could not chroot to %s: %s", root, strerror(errno));
	    exit(1);
	}
    }
    if(pwent) {
	if(setgid(pwent->pw_gid)) {
	    flog(LOG_ERR, "could not switch group to %i: %s", (int)pwent->pw_gid, strerror(errno));
	    exit(1);
	}
	if(setuid(pwent->pw_uid)) {
	    flog(LOG_ERR, "could not switch user to %i: %s", (int)pwent->pw_uid, strerror(errno));
	    exit(1);
	}
    }
    signal(SIGPIPE, SIG_IGN);
    signal(SIGCHLD, SIG_IGN);
    signal(SIGINT, sighandler);
    signal(SIGTERM, sighandler);
    if(daemonize) {
	daemon(0, 0);
    }
    if(pidout != NULL) {
	fprintf(pidout, "%i\n", getpid());
	fclose(pidout);
    }
    d = 0;
    while(!d) {
	switch(ioloop()) {
	case 0:
	    d = 1;
	    break;
	case 1:
	    if(listeners.d > 0) {
		while(listeners.d > 0)
		    resume(listeners.b[0], 0);
		flog(LOG_INFO, "no longer listening");
	    } else {
		d = 1;
	    }
	    break;
	}
    }
    return(0);
}
Commit	Line	Data
	1	/*
	2	ashd - A Sane HTTP Daemon
	3	Copyright (C) 2008 Fredrik Tolf <fredrik@dolda2000.com>
	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 3 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, see <http://www.gnu.org/licenses/>.
	17	*/
	18
	19	#include <stdlib.h>
	20	#include <unistd.h>
	21	#include <stdio.h>
	22	#include <fcntl.h>
	23	#include <string.h>
	24	#include <sys/socket.h>
	25	#include <pwd.h>
	26	#include <sys/signal.h>
	27	#include <errno.h>
	28
	29	#ifdef HAVE_CONFIG_H
	30	#include <config.h>
	31	#endif
	32	#include <utils.h>
	33	#include <mt.h>
	34	#include <mtio.h>
	35	#include <log.h>
	36	#include <req.h>
	37	#include <proc.h>
	38	#include <bufio.h>
	39
	40	#include "htparser.h"
	41
	42	static int plex;
	43	static char *pidfile = NULL;
	44	static int daemonize, usesyslog;
	45	struct mtbuf listeners;
	46
	47	static void trimx(struct hthead *req)
	48	{
	49	int i;
	50
	51	i = 0;
	52	while(i < req->noheaders) {
	53	if(!strncasecmp(req->headers[i][0], "x-ash-", 6)) {
	54	free(req->headers[i][0]);
	55	free(req->headers[i][1]);
	56	free(req->headers[i]);
	57	memmove(req->headers + i, req->headers + i + 1, sizeof(req->headers) (--req->noheaders - i));
	58	} else {
	59	i++;
	60	}
	61	}
	62	}
	63
	64	static struct hthead parsereq(struct bufio in)
	65	{
	66	struct hthead *req;
	67	struct charbuf method, url, ver;
	68	int c;
	69
	70	req = NULL;
	71	bufinit(method);
	72	bufinit(url);
	73	bufinit(ver);
	74	while(1) {
	75	c = biogetc(in);
	76	if(c == ' ') {
	77	break;
	78	} else if((c == EOF) \|\| (c < 32) \|\| (c >= 128)) {
	79	goto fail;
	80	} else {
	81	bufadd(method, c);
	82	if(method.d >= 128)
	83	goto fail;
	84	}
	85	}
	86	while(1) {
	87	c = biogetc(in);
	88	if(c == ' ') {
	89	break;
	90	} else if((c == EOF) \|\| (c < 32)) {
	91	goto fail;
	92	} else {
	93	bufadd(url, c);
	94	if(url.d >= 65536)
	95	goto fail;
	96	}
	97	}
	98	while(1) {
	99	c = biogetc(in);
	100	if(c == 10) {
	101	break;
	102	} else if(c == 13) {
	103	} else if((c == EOF) \|\| (c < 32) \|\| (c >= 128)) {
	104	goto fail;
	105	} else {
	106	bufadd(ver, c);
	107	if(ver.d >= 128)
	108	goto fail;
	109	}
	110	}
	111	bufadd(method, 0);
	112	bufadd(url, 0);
	113	bufadd(ver, 0);
	114	req = mkreq(method.b, url.b, ver.b);
	115	if(parseheadersb(req, in))
	116	goto fail;
	117	trimx(req);
	118	goto out;
	119
	120	fail:
	121	if(req != NULL) {
	122	freehthead(req);
	123	req = NULL;
	124	}
	125	out:
	126	buffree(method);
	127	buffree(url);
	128	buffree(ver);
	129	return(req);
	130	}
	131
	132	static off_t passdata(struct bufio in, struct bufio out, off_t max)
	133	{
	134	ssize_t read;
	135	off_t total;
	136
	137	total = 0;
	138	while(!bioeof(in) && ((max < 0) \|\| (total < max))) {
	139	if((read = biordata(in)) > 0) {
	140	if(max >= 0)
	141	read = min(max - total, read);
	142	if((read = biowritesome(out, in->rbuf.b + in->rh, read)) < 0)
	143	return(-1);
	144	in->rh += read;
	145	total += read;
	146	}
	147	if(biorspace(in) && ((max < 0) \|\| (biordata(in) < max - total)) && (biofillsome(in) < 0))
	148	return(-1);
	149	}
	150	return(total);
	151	}
	152
	153	static int recvchunks(struct bufio in, struct bufio out)
	154	{
	155	size_t read, chlen;
	156	int c, r;
	157
	158	while(1) {
	159	chlen = 0;
	160	r = 0;
	161	while(1) {
	162	c = biogetc(in);
	163	if(c == 10) {
	164	if(!r)
	165	return(-1);
	166	break;
	167	} else if(c == 13) {
	168	} else if((c >= '0') && (c <= '9')) {
	169	chlen = (chlen << 4) + (c - '0');
	170	r = 1;
	171	} else if((c >= 'A') && (c <= 'F')) {
	172	chlen = (chlen << 4) + (c + 10 - 'A');
	173	r = 1;
	174	} else if((c >= 'a') && (c <= 'f')) {
	175	chlen = (chlen << 4) + (c + 10 - 'a');
	176	r = 1;
	177	} else {
	178	/* XXX: Technically, there may be chunk extensions to
	179	* be read, but since that will likely never actually
	180	* happen in practice, I can just as well add support
	181	* for that if it actually does become relevant. */
	182	return(-1);
	183	}
	184	}
	185	if(chlen == 0)
	186	break;
	187	while(chlen > 0) {
	188	if((read = biordata(in)) > 0) {
	189	if((read = biowritesome(out, in->rbuf.b + in->rh, min(read, chlen))) < 0)
	190	return(-1);
	191	in->rh += read;
	192	chlen -= read;
	193	}
	194	if(biorspace(in) && (biordata(in) < chlen) && (biofillsome(in) <= 0))
	195	return(-1);
	196	}
	197	if((biogetc(in) != 13) \|\| (biogetc(in) != 10))
	198	return(-1);
	199	}
	200	/* XXX: Technically, there may be trailers to be read, but that's
	201	* just about as likely as chunk extensions. */
	202	if((biogetc(in) != 13) \|\| (biogetc(in) != 10))
	203	return(-1);
	204	return(0);
	205	}
	206
	207	static int passchunks(struct bufio in, struct bufio out)
	208	{
	209	size_t read;
	210
	211	while(!bioeof(in)) {
	212	if((read = biordata(in)) > 0) {
	213	bioprintf(out, "%zx\r\n", read);
	214	if(biowrite(out, in->rbuf.b + in->rh, read) != read)
	215	return(-1);
	216	in->rh += read;
	217	bioprintf(out, "\r\n");
	218	if(bioflush(out) < 0)
	219	return(-1);
	220	}
	221	if(biorspace(in) && (biofillsome(in) < 0))
	222	return(-1);
	223	}
	224	bioprintf(out, "0\r\n\r\n");
	225	return(0);
	226	}
	227
	228	static int hasheader(struct hthead head, char name, char *val)
	229	{
	230	char *hd;
	231
	232	if((hd = getheader(head, name)) == NULL)
	233	return(0);
	234	return(!strcasecmp(hd, val));
	235	}
	236
	237	static int canonreq(struct hthead *req)
	238	{
	239	char p, p2, *r;
	240	int n;
	241
	242	if(req->url[0] == '/') {
	243	replrest(req, req->url + 1);
	244	if((p = strchr(req->rest, '?')) != NULL)
	245	*p = 0;
	246	return(1);
	247	}
	248	if((p = strstr(req->url, "://")) != NULL) {
	249	n = p - req->url;
	250	if(((n == 4) && !strncasecmp(req->url, "http", 4)) \|\|
	251	((n == 5) && !strncasecmp(req->url, "https", 5))) {
	252	if(getheader(req, "host"))
	253	return(0);
	254	p += 3;
	255	if((p2 = strchr(p, '/')) == NULL) {
	256	headappheader(req, "Host", p);
	257	free(req->url);
	258	req->url = sstrdup("/");
	259	} else {
	260	r = sstrdup(p2);
	261	*(p2++) = 0;
	262	headappheader(req, "Host", p);
	263	free(req->url);
	264	req->url = r;
	265	}
	266	replrest(req, req->url + 1);
	267	if((p = strchr(req->rest, '?')) != NULL)
	268	*p = 0;
	269	return(1);
	270	}
	271	}
	272	return(0);
	273	}
	274
	275	static int http10keep(struct hthead req, struct hthead resp)
	276	{
	277	int fc;
	278
	279	fc = hasheader(resp, "connection", "close");
	280	headrmheader(resp, "connection");
	281	if(!fc && hasheader(req, "connection", "keep-alive")) {
	282	headappheader(resp, "Connection", "Keep-Alive");
	283	return(1);
	284	} else {
	285	return(0);
	286	}
	287	}
	288
	289	static char *connid(void)
	290	{
	291	static struct charbuf cur;
	292	int i;
	293	char *ret;
	294
	295	for(i = 0; i < cur.d; i++) {
	296	if((++cur.b[i]) > 'Z')
	297	cur.b[i] = 'A';
	298	else
	299	goto done;
	300	}
	301	bufadd(cur, 'A');
	302	done:
	303	ret = memcpy(smalloc(cur.d + 1), cur.b, cur.d);
	304	ret[cur.d] = 0;
	305	return(ret);
	306	}
	307
	308	static void passduplex(struct bufio a, int afd, struct bufio b, int bfd)
	309	{
	310	struct selected pfd[4], sel;
	311	struct bufio *sio;
	312	int n, ev;
	313
	314	while(!bioeof(a) && !bioeof(b)) {
	315	biocopybuf(b, a);
	316	biocopybuf(a, b);
	317	n = 0;
	318	if(!a->eof) {
	319	ev = 0;
	320	if(biorspace(a))
	321	ev \|= EV_READ;
	322	if(biowdata(a))
	323	ev \|= EV_WRITE;
	324	if(ev)
	325	pfd[n++] = (struct selected){.fd = afd, .ev = ev};
	326	}
	327	if(!b->eof) {
	328	ev = 0;
	329	if(!b->eof && biorspace(b))
	330	ev \|= EV_READ;
	331	if(biowdata(b))
	332	ev \|= EV_WRITE;
	333	if(ev)
	334	pfd[n++] = (struct selected){.fd = bfd, .ev = ev};
	335	}
	336	sel = mblock(600, n, pfd);
	337	if(sel.fd == afd)
	338	sio = a;
	339	else if(sel.fd == bfd)
	340	sio = b;
	341	else
	342	break;
	343	if((sel.ev & EV_READ) && (biofillsome(sio) < 0))
	344	break;
	345	if((sel.ev & EV_WRITE) && (bioflushsome(sio) < 0))
	346	break;
	347	}
	348	}
	349
	350	void serve(struct bufio in, int infd, struct conn conn)
	351	{
	352	int pfds[2];
	353	struct bufio out, dout;
	354	struct stdiofd *outi;
	355	struct hthead req, resp;
	356	char hd, id;
	357	off_t dlen;
	358	int keep, duplex;
	359
	360	id = connid();
	361	out = NULL;
	362	req = resp = NULL;
	363	while(plex >= 0) {
	364	bioflush(in);
	365	if((req = parsereq(in)) == NULL)
	366	break;
	367	if(!canonreq(req))
	368	break;
	369
	370	headappheader(req, "X-Ash-Connection-ID", id);
	371	if((conn->initreq != NULL) && conn->initreq(conn, req))
	372	break;
	373
	374	if((plex < 0) \|\| block(plex, EV_WRITE, 60) <= 0)
	375	break;
	376	if(socketpair(PF_UNIX, SOCK_STREAM, 0, pfds))
	377	break;
	378	if(sendreq(plex, req, pfds[0]))
	379	break;
	380	close(pfds[0]);
	381	out = mtbioopen(pfds[1], 1, 600, "r+", &outi);
	382
	383	if(getheader(req, "content-type") != NULL) {
	384	if((hd = getheader(req, "content-length")) != NULL) {
	385	dlen = atoo(hd);
	386	if(dlen > 0) {
	387	if(passdata(in, out, dlen) != dlen)
	388	break;
	389	}
	390	} else if(((hd = getheader(req, "transfer-encoding")) != NULL) && !strcasecmp(hd, "chunked")) {
	391	if(recvchunks(in, out))
	392	break;
	393	} else {
	394	/* Ignore rather than abort, to be kinder to broken clients. */
	395	headrmheader(req, "content-type");
	396	}
	397	}
	398	if(bioflush(out))
	399	break;
	400	/* Make sure to send EOF */
	401	shutdown(pfds[1], SHUT_WR);
	402
	403	if((resp = parseresponseb(out)) == NULL)
	404	break;
	405	replstr(&resp->ver, req->ver);
	406
	407	if(!getheader(resp, "server"))
	408	headappheader(resp, "Server", sprintf3("ashd/%s", VERSION));
	409	duplex = hasheader(resp, "x-ash-switch", "duplex");
	410	trimx(resp);
	411
	412	if(duplex) {
	413	if(outi->rights < 0)
	414	break;
	415	writerespb(in, resp);
	416	bioprintf(in, "\r\n");
	417	dout = mtbioopen(outi->rights, 1, 600, "r+", NULL);
	418	passduplex(in, infd, dout, outi->rights);
	419	outi->rights = -1;
	420	bioclose(dout);
	421	break;
	422	} else if(!strcasecmp(req->ver, "HTTP/1.0")) {
	423	if(!strcasecmp(req->method, "head")) {
	424	keep = http10keep(req, resp);
	425	writerespb(in, resp);
	426	bioprintf(in, "\r\n");
	427	} else if((hd = getheader(resp, "content-length")) != NULL) {
	428	keep = http10keep(req, resp);
	429	dlen = atoo(hd);
	430	writerespb(in, resp);
	431	bioprintf(in, "\r\n");
	432	if(passdata(out, in, dlen) != dlen)
	433	break;
	434	} else {
	435	headrmheader(resp, "connection");
	436	writerespb(in, resp);
	437	bioprintf(in, "\r\n");
	438	passdata(out, in, -1);
	439	break;
	440	}
	441	if(!keep)
	442	break;
	443	} else if(!strcasecmp(req->ver, "HTTP/1.1")) {
	444	if(!strcasecmp(req->method, "head")) {
	445	writerespb(in, resp);
	446	bioprintf(in, "\r\n");
	447	} else if((hd = getheader(resp, "content-length")) != NULL) {
	448	writerespb(in, resp);
	449	bioprintf(in, "\r\n");
	450	dlen = atoo(hd);
	451	if(passdata(out, in, dlen) != dlen)
	452	break;
	453	} else if(!getheader(resp, "transfer-encoding")) {
	454	headappheader(resp, "Transfer-Encoding", "chunked");
	455	writerespb(in, resp);
	456	bioprintf(in, "\r\n");
	457	if(passchunks(out, in))
	458	break;
	459	} else {
	460	writerespb(in, resp);
	461	bioprintf(in, "\r\n");
	462	passdata(out, in, -1);
	463	break;
	464	}
	465	if(hasheader(req, "connection", "close") \|\| hasheader(resp, "connection", "close"))
	466	break;
	467	} else {
	468	break;
	469	}
	470
	471	bioclose(out);
	472	out = NULL;
	473	freehthead(req);
	474	freehthead(resp);
	475	req = resp = NULL;
	476	}
	477
	478	if(out != NULL)
	479	bioclose(out);
	480	if(req != NULL)
	481	freehthead(req);
	482	if(resp != NULL)
	483	freehthead(resp);
	484	bioclose(in);
	485	free(id);
	486	}
	487
	488	static void plexwatch(struct muth *muth, va_list args)
	489	{
	490	vavar(int, fd);
	491	char *buf;
	492	int i, s, ret;
	493
	494	s = 0;
	495	while(1) {
	496	if(block(fd, EV_READ, 0) == 0)
	497	break;
	498	buf = smalloc(65536);
	499	ret = recv(fd, buf, 65536, 0);
	500	if(ret < 0) {
	501	flog(LOG_WARNING, "received error on rootplex read channel: %s", strerror(errno));
	502	exit(1);
	503	} else if(ret == 0) {
	504	s = 1;
	505	free(buf);
	506	break;
	507	}
	508	/* Maybe I'd like to implement some protocol in this direction
	509	* some day... */
	510	free(buf);
	511	}
	512	shutdown(plex, SHUT_RDWR);
	513	for(i = 0; i < listeners.d; i++) {
	514	if(listeners.b[i] == muth)
	515	bufdel(listeners, i);
	516	}
	517	if(s) {
	518	flog(LOG_INFO, "root handler exited, so shutting down listening...");
	519	while(listeners.d > 0)
	520	resume(listeners.b[0], 0);
	521	}
	522	}
	523
	524	static void initroot(void *uu)
	525	{
	526	int fd;
	527
	528	setsid();
	529	if(daemonize) {
	530	chdir("/");
	531	if((fd = open("/dev/null", O_RDWR)) >= 0) {
	532	dup2(fd, 0);
	533	dup2(fd, 1);
	534	dup2(fd, 2);
	535	close(fd);
	536	}
	537	}
	538	if(usesyslog)
	539	putenv("ASHD_USESYSLOG=1");
	540	else
	541	unsetenv("ASHD_USESYSLOG");
	542	}
	543
	544	static void usage(FILE *out)
	545	{
	546	fprintf(out, "usage: htparser [-hSf] [-u USER] [-r ROOT] [-p PIDFILE] PORTSPEC... -- ROOT [ARGS...]\n");
	547	fprintf(out, "\twhere PORTSPEC is HANDLER[:PAR[=VAL][(,PAR[=VAL])...]] (try HANDLER:help)\n");
	548	fprintf(out, "\tavailable handlers are `plain' and `ssl'.\n");
	549	}
	550
	551	static void addport(char *spec)
	552	{
	553	char nm, p, p2, n;
	554	struct charvbuf pars, vals;
	555
	556	bufinit(pars);
	557	bufinit(vals);
	558	if((p = strchr(spec, ':')) == NULL) {
	559	nm = spec;
	560	} else {
	561	nm = spec;
	562	*(p++) = 0;
	563	do {
	564	if((n = strchr(p, ',')) != NULL)
	565	*(n++) = 0;
	566	if((p2 = strchr(p, '=')) != NULL)
	567	*(p2++) = 0;
	568	if(!*p) {
	569	usage(stderr);
	570	exit(1);
	571	}
	572	bufadd(pars, p);
	573	if(p2)
	574	bufadd(vals, p2);
	575	else
	576	bufadd(vals, "");
	577	} while((p = n) != NULL);
	578	}
	579
	580	/* XXX: It would be nice to decentralize this, but, meh... */
	581	if(!strcmp(nm, "plain")) {
	582	handleplain(pars.d, pars.b, vals.b);
	583	#ifdef HAVE_GNUTLS
	584	} else if(!strcmp(nm, "ssl")) {
	585	handlegnussl(pars.d, pars.b, vals.b);
	586	#endif
	587	} else {
	588	flog(LOG_ERR, "htparser: unknown port handler `%s'", nm);
	589	exit(1);
	590	}
	591
	592	buffree(pars);
	593	buffree(vals);
	594	}
	595
	596	static void sighandler(int sig)
	597	{
	598	exitioloop(1);
	599	}
	600
	601	int main(int argc, char **argv)
	602	{
	603	int c, d;
	604	int i, s1;
	605	char *root;
	606	FILE *pidout;
	607	struct passwd *pwent;
	608
	609	daemonize = usesyslog = 0;
	610	root = NULL;
	611	pwent = NULL;
	612	while((c = getopt(argc, argv, "+hSfu:r:p:")) >= 0) {
	613	switch(c) {
	614	case 'h':
	615	usage(stdout);
	616	exit(0);
	617	case 'f':
	618	daemonize = 1;
	619	break;
	620	case 'S':
	621	usesyslog = 1;
	622	break;
	623	case 'u':
	624	if((pwent = getpwnam(optarg)) == NULL) {
	625	flog(LOG_ERR, "could not find user %s", optarg);
	626	exit(1);
	627	}
	628	break;
	629	case 'r':
	630	root = optarg;
	631	break;
	632	case 'p':
	633	pidfile = optarg;
	634	break;
	635	default:
	636	usage(stderr);
	637	exit(1);
	638	}
	639	}
	640	s1 = 0;
	641	for(i = optind; i < argc; i++) {
	642	if(!strcmp(argv[i], "--"))
	643	break;
	644	s1 = 1;
	645	addport(argv[i]);
	646	}
	647	if(!s1 \|\| (i == argc)) {
	648	usage(stderr);
	649	exit(1);
	650	}
	651	if((plex = stdmkchild(argv + ++i, initroot, NULL)) < 0) {
	652	flog(LOG_ERR, "could not spawn root multiplexer: %s", strerror(errno));
	653	return(1);
	654	}
	655	bufadd(listeners, mustart(plexwatch, plex));
	656	pidout = NULL;
	657	if(pidfile != NULL) {
	658	if((pidout = fopen(pidfile, "w")) == NULL) {
	659	flog(LOG_ERR, "could not open %s for writing: %s", pidfile, strerror(errno));
	660	return(1);
	661	}
	662	}
	663	if(usesyslog)
	664	opensyslog();
	665	if(root) {
	666	if(chdir(root) \|\| chroot(root)) {
	667	flog(LOG_ERR, "could not chroot to %s: %s", root, strerror(errno));
	668	exit(1);
	669	}
	670	}
	671	if(pwent) {
	672	if(setgid(pwent->pw_gid)) {
	673	flog(LOG_ERR, "could not switch group to %i: %s", (int)pwent->pw_gid, strerror(errno));
	674	exit(1);
	675	}
	676	if(setuid(pwent->pw_uid)) {
	677	flog(LOG_ERR, "could not switch user to %i: %s", (int)pwent->pw_uid, strerror(errno));
	678	exit(1);
	679	}
	680	}
	681	signal(SIGPIPE, SIG_IGN);
	682	signal(SIGCHLD, SIG_IGN);
	683	signal(SIGINT, sighandler);
	684	signal(SIGTERM, sighandler);
	685	if(daemonize) {
	686	daemon(0, 0);
	687	}
	688	if(pidout != NULL) {
	689	fprintf(pidout, "%i\n", getpid());
	690	fclose(pidout);
	691	}
	692	d = 0;
	693	while(!d) {
	694	switch(ioloop()) {
	695	case 0:
	696	d = 1;
	697	break;
	698	case 1:
	699	if(listeners.d > 0) {
	700	while(listeners.d > 0)
	701	resume(listeners.b[0], 0);
	702	flog(LOG_INFO, "no longer listening");
	703	} else {
	704	d = 1;
	705	}
	706	break;
	707	}
	708	}
	709	return(0);
	710	}