[ashd.git] / src / callscgi.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/>.
*/

/*
 * XXX: All the various ways to start a child process makes this
 * program quite ugly at the moment. It is unclear whether it is
 * meaningfully possible to unify them better than they currently are.
 */

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <ctype.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netdb.h>
#include <signal.h>
#include <errno.h>

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

static char **progspec;
static char *sockid, *unspec, *inspec;
static int nolisten;
static struct sockaddr *curaddr;
static size_t caddrlen;
static int cafamily, isanon;
static pid_t child;

static struct addrinfo *resolv(int flags)
{
    int ret;
    struct addrinfo *ai, h;
    char *name, *srv, *p;
    
    if((p = strchr(inspec, ':')) != NULL) {
	name = smalloc(p - inspec + 1);
	memcpy(name, inspec, p - inspec);
	name[p - inspec] = 0;
	srv = p + 1;
    } else {
	name = sstrdup("localhost");
	srv = inspec;
    }
    memset(&h, 0, sizeof(h));
    h.ai_family = AF_UNSPEC;
    h.ai_socktype = SOCK_STREAM;
    h.ai_flags = flags;
    ret = getaddrinfo(name, srv, &h, &ai);
    free(name);
    if(ret != 0) {
	flog(LOG_ERR, "could not resolve TCP specification `%s': %s", inspec, gai_strerror(ret));
	exit(1);
    }
    return(ai);
}

static char *mksockid(char *sockid)
{
    char *home;
    
    home = getenv("HOME");
    if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
	return(sprintf3("%s/.ashd/sockets/scgi-p-%s", home, sockid));
    return(sprintf3("/tmp/scgi-%i-%s", getuid(), sockid));
}

static char *mkanonid(void)
{
    char *home;
    char *tmpl;
    int fd;
    
    home = getenv("HOME");
    if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
	tmpl = sprintf2("%s/.ashd/sockets/scgi-a-XXXXXX", home);
    else
	tmpl = sprintf2("/tmp/scgi-a-%i-XXXXXX", getuid());
    if((fd = mkstemp(tmpl)) < 0) {
	flog(LOG_ERR, "could not create anonymous socket `%s': %s", tmpl, strerror(errno));
	exit(1);
    }
    close(fd);
    unlink(tmpl);
    return(tmpl);
}

static void startlisten(void)
{
    int i, fd;
    struct addrinfo *ai, *cai;
    char *unpath;
    struct sockaddr_un unm;
    char *aname;
    
    isanon = 0;
    if(inspec != NULL) {
	fd = -1;
	for(cai = ai = resolv(AI_PASSIVE); cai != NULL; cai = cai->ai_next) {
	    if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
		continue;
	    if(bind(fd, cai->ai_addr, cai->ai_addrlen)) {
		close(fd);
		fd = -1;
		continue;
	    }
	    if(listen(fd, 128)) {
		close(fd);
		fd = -1;
		continue;
	    }
	    break;
	}
	freeaddrinfo(ai);
	if(fd < 0) {
	    flog(LOG_ERR, "could not bind to specified TCP address: %s", strerror(errno));
	    exit(1);
	}
    } else if((unspec != NULL) || (sockid != NULL)) {
	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	    flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	    exit(1);
	}
	if(unspec != NULL)
	    unpath = unspec;
	else
	    unpath = mksockid(sockid);
	unlink(unpath);
	unm.sun_family = AF_UNIX;
	strcpy(unm.sun_path, unpath);
	if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
	    flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
	    exit(1);
	}
	if(listen(fd, 128)) {
	    flog(LOG_ERR, "listen: %s", strerror(errno));
	    exit(1);
	}
    } else {
	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	    flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	    exit(1);
	}
	memset(&unm, 0, sizeof(unm));
	aname = mkanonid();
	unm.sun_family = AF_UNIX;
	strcpy(unm.sun_path, aname);
	free(aname);
	if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
	    flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
	    exit(1);
	}
	if(listen(fd, 128)) {
	    flog(LOG_ERR, "listen: %s", strerror(errno));
	    exit(1);
	}
	
	curaddr = smalloc(caddrlen = sizeof(unm));
	memcpy(curaddr, &unm, sizeof(unm));
	cafamily = AF_UNIX;
	isanon = 1;
    }
    if((child = fork()) < 0) {
	flog(LOG_ERR, "could not fork: %s", strerror(errno));
	exit(1);
    }
    if(child == 0) {
	dup2(fd, 0);
	for(i = 3; i < FD_SETSIZE; i++)
	    close(i);
	execvp(*progspec, progspec);
	flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
	_exit(127);
    }
    close(fd);
}

static void startnolisten(void)
{
    int i, fd;
    
    if((child = fork()) < 0) {
	flog(LOG_ERR, "could not fork: %s", strerror(errno));
	exit(1);
    }
    if(child == 0) {
	for(i = 3; i < FD_SETSIZE; i++)
	    close(i);
	if((fd = open("/dev/null", O_RDONLY)) < 0) {
	    flog(LOG_ERR, "/dev/null: %s", strerror(errno));
	    _exit(127);
	}
	dup2(fd, 0);
	close(fd);
	execvp(*progspec, progspec);
	flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
	_exit(127);
    }
}

static int sconnect(void)
{
    int fd;
    int err;
    socklen_t errlen;

    fd = socket(cafamily, SOCK_STREAM, 0);
    fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
    while(1) {
	if(connect(fd, curaddr, caddrlen)) {
	    if(errno == EINPROGRESS) {
		block(fd, EV_WRITE, 30);
		errlen = sizeof(err);
		if(getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errlen) || ((errno = err) != 0)) {
		    close(fd);
		    return(-1);
		}
		return(fd);
	    }
	    close(fd);
	    return(-1);
	}
	return(fd);
    }
}

static int econnect(void)
{
    int fd;
    struct addrinfo *ai, *cai;
    int tries;
    char *unpath;
    struct sockaddr_un unm;
    
    tries = 0;
retry:
    if(inspec != NULL) {
	fd = -1;
	for(cai = ai = resolv(0); cai != NULL; cai = cai->ai_next) {
	    if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
		continue;
	    if(connect(fd, cai->ai_addr, cai->ai_addrlen)) {
		close(fd);
		fd = -1;
		continue;
	    }
	    break;
	}
	if(fd < 0) {
	    if(tries++ < nolisten) {
		sleep(1);
		goto retry;
	    }
	    flog(LOG_ERR, "could not connect to specified TCP address: %s", strerror(errno));
	    exit(1);
	}
	curaddr = smalloc(caddrlen = cai->ai_addrlen);
	memcpy(curaddr, cai->ai_addr, caddrlen);
	cafamily = cai->ai_family;
	isanon = 0;
	freeaddrinfo(ai);
	return(fd);
    } else if((unspec != NULL) || (sockid != NULL)) {
	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	    flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	    exit(1);
	}
	if(unspec != NULL)
	    unpath = unspec;
	else
	    unpath = mksockid(sockid);
	unlink(unpath);
	unm.sun_family = AF_UNIX;
	strcpy(unm.sun_path, unpath);
	if(connect(fd, (struct sockaddr *)&unm, sizeof(unm))) {
	    close(fd);
	    if(tries++ < nolisten) {
		sleep(1);
		goto retry;
	    }
	    flog(LOG_ERR, "could not connect to Unix socket `%s': %s", unspec, strerror(errno));
	    exit(1);
	}
	curaddr = smalloc(caddrlen = sizeof(unm));
	memcpy(curaddr, &unm, sizeof(unm));
	cafamily = AF_UNIX;
	isanon = 0;
	return(fd);
    } else {
	flog(LOG_ERR, "callscgi: cannot use an anonymous socket without a program to start");
	exit(1);
    }
}

static int startconn(void)
{
    if(*progspec) {
	if(nolisten == 0)
	    startlisten();
	else
	    startnolisten();
    }
    if(curaddr != NULL)
	return(sconnect());
    return(econnect());
}

static void killcuraddr(void)
{
    if(curaddr == NULL)
	return;
    if(isanon) {
	unlink(((struct sockaddr_un *)curaddr)->sun_path);
	if(child > 0)
	    kill(child, SIGTERM);
    }
    free(curaddr);
    curaddr = NULL;
}

static int reconn(void)
{
    int fd;
    
    if(curaddr != NULL) {
	if((fd = sconnect()) >= 0)
	    return(fd);
	killcuraddr();
    }
    return(startconn());
}

static off_t passdata(FILE *in, FILE *out)
{
    size_t read;
    off_t total;
    char buf[8192];
    
    total = 0;
    while(!feof(in)) {
	read = fread(buf, 1, sizeof(buf), in);
	if(ferror(in))
	    return(-1);
	if(fwrite(buf, 1, read, out) != read)
	    return(-1);
	total += read;
    }
    return(total);
}

static void bufaddenv(struct charbuf *dst, char *name, char *fmt, ...)
{
    va_list args;
    
    bufcatstr2(*dst, name);
    va_start(args, fmt);
    bvprintf(dst, fmt, args);
    va_end(args);
    bufadd(*dst, 0);
}

static char *absolutify(char *file)
{
    static int inited = 0;
    static char cwd[1024];
    
    if(*file != '/') {
	if(!inited) {
	    getcwd(cwd, sizeof(cwd));
	    inited = 1;
	}
	return(sprintf2("%s/%s", cwd, file));
    }
    return(sstrdup(file));
}

/* Mostly copied from callcgi. */
static void mkcgienv(struct hthead *req, struct charbuf *dst)
{
    int i;
    char *url, *pi, *tmp, *qp, *h, *p;
    
    bufaddenv(dst, "SERVER_SOFTWARE", "ashd/%s", VERSION);
    bufaddenv(dst, "GATEWAY_INTERFACE", "CGI/1.1");
    bufaddenv(dst, "SCGI", "1");
    bufaddenv(dst, "SERVER_PROTOCOL", "%s", req->ver);
    bufaddenv(dst, "REQUEST_METHOD", "%s", req->method);
    bufaddenv(dst, "REQUEST_URI", "%s", req->url);
    url = sstrdup(req->url);
    if((qp = strchr(url, '?')) != NULL)
	*(qp++) = 0;
    /* XXX: This is an ugly hack (I think), but though I can think of
     * several alternatives, none seem to be better. */
    if(*req->rest && (strlen(url) >= strlen(req->rest)) &&
       !strcmp(req->rest, url + strlen(url) - strlen(req->rest))) {
	url[strlen(url) - strlen(req->rest)] = 0;
    }
    if((pi = unquoteurl(req->rest)) == NULL)
	pi = sstrdup(req->rest);
    if(!strcmp(url, "/")) {
	/* This seems to be normal CGI behavior, but see callcgi.c for
	 * details. */
	url[0] = 0;
	pi = sprintf2("/%s", tmp = pi);
	free(tmp);
    }
    bufaddenv(dst, "PATH_INFO", pi);
    bufaddenv(dst, "SCRIPT_NAME", url);
    bufaddenv(dst, "QUERY_STRING", "%s", qp?qp:"");
    free(pi);
    free(url);
    if((h = getheader(req, "Host")) != NULL)
	bufaddenv(dst, "SERVER_NAME", "%s", h);
    if((h = getheader(req, "X-Ash-Server-Address")) != NULL)
	bufaddenv(dst, "SERVER_ADDR", "%s", h);
    if((h = getheader(req, "X-Ash-Server-Port")) != NULL)
	bufaddenv(dst, "SERVER_PORT", "%s", h);
    if((h = getheader(req, "X-Ash-Remote-User")) != NULL)
	bufaddenv(dst, "REMOTE_USER", "%s", h);
    if(((h = getheader(req, "X-Ash-Protocol")) != NULL) && !strcmp(h, "https"))
	bufaddenv(dst, "HTTPS", "on");
    if((h = getheader(req, "X-Ash-Address")) != NULL)
	bufaddenv(dst, "REMOTE_ADDR", "%s", h);
    if((h = getheader(req, "X-Ash-Port")) != NULL)
	bufaddenv(dst, "REMOTE_PORT", "%s", h);
    if((h = getheader(req, "Content-Type")) != NULL)
	bufaddenv(dst, "CONTENT_TYPE", "%s", h);
    if((h = getheader(req, "Content-Length")) != NULL)
	bufaddenv(dst, "CONTENT_LENGTH", "%s", h);
    else
	bufaddenv(dst, "CONTENT_LENGTH", "0");
    if((h = getheader(req, "X-Ash-File")) != NULL) {
	h = absolutify(h);
	bufaddenv(dst, "SCRIPT_FILENAME", "%s", h);
	free(h);
    }
    for(i = 0; i < req->noheaders; i++) {
	h = sprintf2("HTTP_%s", req->headers[i][0]);
	for(p = h; *p; p++) {
	    if(isalnum(*p))
		*p = toupper(*p);
	    else
		*p = '_';
	}
	bufcatstr2(*dst, h);
	free(h);
	bufcatstr2(*dst, req->headers[i][1]);
    }
}

static struct hthead *parseresp(FILE *in)
{
    struct hthead *resp;
    char *st, *p;
    
    omalloc(resp);
    resp->ver = sstrdup("HTTP/1.1");
    if(parseheaders(resp, in)) {
	freehthead(resp);
	return(NULL);
    }
    if((st = getheader(resp, "Status")) != NULL) {
	if((p = strchr(st, ' ')) != NULL) {
	    *(p++) = 0;
	    resp->code = atoi(st);
	    resp->msg = sstrdup(p);
	} else {
	    resp->code = atoi(st);
	    resp->msg = sstrdup(httpdefstatus(resp->code));
	}
	headrmheader(resp, "Status");
    } else if(getheader(resp, "Location")) {
	resp->code = 303;
	resp->msg = sstrdup("See Other");
    } else {
	resp->code = 200;
	resp->msg = sstrdup("OK");
    }
    return(resp);
}

static void serve(struct muth *muth, va_list args)
{
    vavar(struct hthead *, req);
    vavar(int, fd);
    vavar(int, sfd);
    FILE *is, *os;
    struct charbuf head;
    struct hthead *resp;
    
    sfd = reconn();
    is = mtstdopen(fd, 1, 60, "r+");
    os = mtstdopen(sfd, 1, 600, "r+");
    
    bufinit(head);
    mkcgienv(req, &head);
    fprintf(os, "%zi:", head.d);
    fwrite(head.b, head.d, 1, os);
    fputc(',', os);
    buffree(head);
    if(passdata(is, os) < 0)
	goto out;
    
    if((resp = parseresp(os)) == NULL)
	goto out;
    writeresp(is, resp);
    freehthead(resp);
    fputc('\n', is);
    if(passdata(os, is) < 0)
	goto out;
    
out:
    freehthead(req);
    fclose(is);
    fclose(os);
}

static void listenloop(struct muth *muth, va_list args)
{
    vavar(int, lfd);
    int fd;
    struct hthead *req;
    
    while(1) {
	block(0, EV_READ, 0);
	if((fd = recvreq(lfd, &req)) < 0) {
	    if(errno != 0)
		flog(LOG_ERR, "recvreq: %s", strerror(errno));
	    break;
	}
	mustart(serve, req, fd);
    }
}

static void sigign(int sig)
{
}

static void sigexit(int sig)
{
    shutdown(0, SHUT_RDWR);
}

static void usage(FILE *out)
{
    fprintf(out, "usage: callscgi [-h] [-N RETRIES] [-i ID] [-u UNIX-PATH] [-t [HOST:]TCP-PORT] [PROGRAM [ARGS...]]\n");
}

int main(int argc, char **argv)
{
    int c;
    
    while((c = getopt(argc, argv, "+hN:i:u:t:")) >= 0) {
	switch(c) {
	case 'h':
	    usage(stdout);
	    exit(0);
	case 'N':
	    nolisten = atoi(optarg);
	    break;
	case 'i':
	    sockid = optarg;
	    break;
	case 'u':
	    unspec = optarg;
	    break;
	case 't':
	    inspec = optarg;
	    break;
	default:
	    usage(stderr);
	    exit(1);
	}
    }
    progspec = argv + optind;
    if(((sockid != NULL) + (unspec != NULL) + (inspec != NULL)) > 1) {
	flog(LOG_ERR, "callscgi: at most one of -i, -u or -t may be given");
	exit(1);
    }
    signal(SIGCHLD, SIG_IGN);
    signal(SIGPIPE, sigign);
    signal(SIGINT, sigexit);
    signal(SIGTERM, sigexit);
    mustart(listenloop, 0);
    atexit(killcuraddr);
    ioloop();
    return(0);
}
Commit	Line	Data
f89ce57a FT	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	/*
	20	* XXX: All the various ways to start a child process makes this
	21	* program quite ugly at the moment. It is unclear whether it is
	22	* meaningfully possible to unify them better than they currently are.
	23	*/
	24
	25	#include <stdlib.h>
	26	#include <stdio.h>
	27	#include <unistd.h>
	28	#include <string.h>
	29	#include <fcntl.h>
	30	#include <ctype.h>
	31	#include <sys/socket.h>
	32	#include <sys/un.h>
	33	#include <netinet/in.h>
	34	#include <netdb.h>
cc5adcf9	35	#include <signal.h>
f89ce57a FT	36	#include <errno.h>
	37
	38	#ifdef HAVE_CONFIG_H
	39	#include <config.h>
	40	#endif
	41	#include <utils.h>
	42	#include <req.h>
62e76c42	43	#include <resp.h>
f89ce57a FT	44	#include <log.h>
	45	#include <mt.h>
	46	#include <mtio.h>
	47
	48	static char **progspec;
	49	static char sockid, unspec, *inspec;
	50	static int nolisten;
	51	static struct sockaddr *curaddr;
	52	static size_t caddrlen;
	53	static int cafamily, isanon;
	54	static pid_t child;
	55
	56	static struct addrinfo *resolv(int flags)
	57	{
	58	int ret;
	59	struct addrinfo *ai, h;
	60	char name, srv, *p;
	61
	62	if((p = strchr(inspec, ':')) != NULL) {
	63	name = smalloc(p - inspec + 1);
	64	memcpy(name, inspec, p - inspec);
	65	name[p - inspec] = 0;
	66	srv = p + 1;
	67	} else {
	68	name = sstrdup("localhost");
	69	srv = inspec;
	70	}
	71	memset(&h, 0, sizeof(h));
	72	h.ai_family = AF_UNSPEC;
	73	h.ai_socktype = SOCK_STREAM;
	74	h.ai_flags = flags;
	75	ret = getaddrinfo(name, srv, &h, &ai);
	76	free(name);
	77	if(ret != 0) {
	78	flog(LOG_ERR, "could not resolve TCP specification `%s': %s", inspec, gai_strerror(ret));
	79	exit(1);
	80	}
	81	return(ai);
	82	}
	83
	84	static char mksockid(char sockid)
	85	{
	86	char *home;
	87
	88	home = getenv("HOME");
	89	if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
	90	return(sprintf3("%s/.ashd/sockets/scgi-p-%s", home, sockid));
	91	return(sprintf3("/tmp/scgi-%i-%s", getuid(), sockid));
	92	}
	93
	94	static char *mkanonid(void)
	95	{
	96	char *home;
	97	char *tmpl;
	98	int fd;
	99
	100	home = getenv("HOME");
	101	if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
1376c0cd	102	tmpl = sprintf2("%s/.ashd/sockets/scgi-a-XXXXXX", home);
f89ce57a FT	103	else
	104	tmpl = sprintf2("/tmp/scgi-a-%i-XXXXXX", getuid());
	105	if((fd = mkstemp(tmpl)) < 0) {
	106	flog(LOG_ERR, "could not create anonymous socket `%s': %s", tmpl, strerror(errno));
	107	exit(1);
	108	}
1376c0cd	109	close(fd);
f89ce57a FT	110	unlink(tmpl);
	111	return(tmpl);
	112	}
	113
	114	static void startlisten(void)
	115	{
	116	int i, fd;
	117	struct addrinfo ai, cai;
	118	char *unpath;
	119	struct sockaddr_un unm;
	120	char *aname;
	121
	122	isanon = 0;
	123	if(inspec != NULL) {
	124	fd = -1;
	125	for(cai = ai = resolv(AI_PASSIVE); cai != NULL; cai = cai->ai_next) {
	126	if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
	127	continue;
	128	if(bind(fd, cai->ai_addr, cai->ai_addrlen)) {
	129	close(fd);
	130	fd = -1;
	131	continue;
	132	}
	133	if(listen(fd, 128)) {
	134	close(fd);
	135	fd = -1;
	136	continue;
	137	}
	138	break;
	139	}
	140	freeaddrinfo(ai);
	141	if(fd < 0) {
	142	flog(LOG_ERR, "could not bind to specified TCP address: %s", strerror(errno));
	143	exit(1);
	144	}
	145	} else if((unspec != NULL) \|\| (sockid != NULL)) {
	146	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	147	flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	148	exit(1);
	149	}
	150	if(unspec != NULL)
	151	unpath = unspec;
	152	else
	153	unpath = mksockid(sockid);
	154	unlink(unpath);
	155	unm.sun_family = AF_UNIX;
	156	strcpy(unm.sun_path, unpath);
	157	if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
	158	flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
	159	exit(1);
	160	}
	161	if(listen(fd, 128)) {
	162	flog(LOG_ERR, "listen: %s", strerror(errno));
	163	exit(1);
	164	}
	165	} else {
	166	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	167	flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	168	exit(1);
	169	}
	170	memset(&unm, 0, sizeof(unm));
	171	aname = mkanonid();
	172	unm.sun_family = AF_UNIX;
	173	strcpy(unm.sun_path, aname);
174	free(aname);
175	if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
176	flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
177	exit(1);
178	}
179	if(listen(fd, 128)) {
180	flog(LOG_ERR, "listen: %s", strerror(errno));
181	exit(1);
182	}
183
184	curaddr = smalloc(caddrlen = sizeof(unm));
185	memcpy(curaddr, &unm, sizeof(unm));
186	cafamily = AF_UNIX;
187	isanon = 1;
188	}
189	if((child = fork()) < 0) {
190	flog(LOG_ERR, "could not fork: %s", strerror(errno));
191	exit(1);
192	}
193	if(child == 0) {
194	dup2(fd, 0);
195	for(i = 3; i < FD_SETSIZE; i++)
196	close(i);
197	execvp(*progspec, progspec);
7b9c1cff	198	flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
107aa2ef	199	_exit(127);
f89ce57a FT	200	}
	201	close(fd);
	202	}
	203
	204	static void startnolisten(void)
	205	{
02cb2a3d	206	int i, fd;
f89ce57a FT	207
	208	if((child = fork()) < 0) {
	209	flog(LOG_ERR, "could not fork: %s", strerror(errno));
	210	exit(1);
	211	}
	212	if(child == 0) {
	213	for(i = 3; i < FD_SETSIZE; i++)
	214	close(i);
02cb2a3d FT	215	if((fd = open("/dev/null", O_RDONLY)) < 0) {
02cb2a3d FT	216	flog(LOG_ERR, "/dev/null: %s", strerror(errno));
107aa2ef	217	_exit(127);
02cb2a3d FT	218	}
	219	dup2(fd, 0);
	220	close(fd);
f89ce57a	221	execvp(*progspec, progspec);
7b9c1cff	222	flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
107aa2ef	223	_exit(127);
f89ce57a FT	224	}
	225	}
	226
	227	static int sconnect(void)
	228	{
	229	int fd;
	230	int err;
	231	socklen_t errlen;
	232
	233	fd = socket(cafamily, SOCK_STREAM, 0);
	234	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) \| O_NONBLOCK);
	235	while(1) {
	236	if(connect(fd, curaddr, caddrlen)) {
	237	if(errno == EINPROGRESS) {
	238	block(fd, EV_WRITE, 30);
	239	errlen = sizeof(err);
	240	if(getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errlen) \|\| ((errno = err) != 0)) {
	241	close(fd);
	242	return(-1);
	243	}
	244	return(fd);
	245	}
	246	close(fd);
	247	return(-1);
	248	}
	249	return(fd);
	250	}
	251	}
	252
	253	static int econnect(void)
	254	{
	255	int fd;
	256	struct addrinfo ai, cai;
	257	int tries;
	258	char *unpath;
	259	struct sockaddr_un unm;
	260
	261	tries = 0;
	262	retry:
	263	if(inspec != NULL) {
	264	fd = -1;
	265	for(cai = ai = resolv(0); cai != NULL; cai = cai->ai_next) {
	266	if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
	267	continue;
	268	if(connect(fd, cai->ai_addr, cai->ai_addrlen)) {
	269	close(fd);
	270	fd = -1;
	271	continue;
	272	}
	273	break;
	274	}
f89ce57a	275	if(fd < 0) {
02cb2a3d FT	276	if(tries++ < nolisten) {
	277	sleep(1);
	278	goto retry;
	279	}
f89ce57a FT	280	flog(LOG_ERR, "could not connect to specified TCP address: %s", strerror(errno));
	281	exit(1);
	282	}
	283	curaddr = smalloc(caddrlen = cai->ai_addrlen);
	284	memcpy(curaddr, cai->ai_addr, caddrlen);
	285	cafamily = cai->ai_family;
	286	isanon = 0;
	287	freeaddrinfo(ai);
	288	return(fd);
	289	} else if((unspec != NULL) \|\| (sockid != NULL)) {
	290	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	291	flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	292	exit(1);
	293	}
	294	if(unspec != NULL)
	295	unpath = unspec;
	296	else
	297	unpath = mksockid(sockid);
	298	unlink(unpath);
	299	unm.sun_family = AF_UNIX;
	300	strcpy(unm.sun_path, unpath);
	301	if(connect(fd, (struct sockaddr *)&unm, sizeof(unm))) {
	302	close(fd);
	303	if(tries++ < nolisten) {
	304	sleep(1);
	305	goto retry;
	306	}
	307	flog(LOG_ERR, "could not connect to Unix socket `%s': %s", unspec, strerror(errno));
	308	exit(1);
	309	}
	310	curaddr = smalloc(caddrlen = sizeof(unm));
	311	memcpy(curaddr, &unm, sizeof(unm));
	312	cafamily = AF_UNIX;
	313	isanon = 0;
	314	return(fd);
	315	} else {
425eccf6	316	flog(LOG_ERR, "callscgi: cannot use an anonymous socket without a program to start");
f89ce57a FT	317	exit(1);
	318	}
	319	}
	320
	321	static int startconn(void)
	322	{
	323	if(*progspec) {
	324	if(nolisten == 0)
	325	startlisten();
	326	else
	327	startnolisten();
	328	}
	329	if(curaddr != NULL)
	330	return(sconnect());
	331	return(econnect());
	332	}
	333
	334	static void killcuraddr(void)
	335	{
	336	if(curaddr == NULL)
	337	return;
	338	if(isanon) {
	339	unlink(((struct sockaddr_un *)curaddr)->sun_path);
	340	if(child > 0)
	341	kill(child, SIGTERM);
	342	}
	343	free(curaddr);
	344	curaddr = NULL;
	345	}
	346
	347	static int reconn(void)
	348	{
	349	int fd;
	350
	351	if(curaddr != NULL) {
	352	if((fd = sconnect()) >= 0)
	353	return(fd);
	354	killcuraddr();
	355	}
	356	return(startconn());
	357	}
	358
	359	static off_t passdata(FILE in, FILE out)
	360	{
	361	size_t read;
	362	off_t total;
	363	char buf[8192];
	364
	365	total = 0;
	366	while(!feof(in)) {
	367	read = fread(buf, 1, sizeof(buf), in);
	368	if(ferror(in))
	369	return(-1);
	370	if(fwrite(buf, 1, read, out) != read)
	371	return(-1);
	372	total += read;
	373	}
	374	return(total);
	375	}
	376
	377	static void bufaddenv(struct charbuf dst, char name, char *fmt, ...)
	378	{
	379	va_list args;
	380
381	bufcatstr2(*dst, name);
382	va_start(args, fmt);
383	bvprintf(dst, fmt, args);
384	va_end(args);
385	bufadd(*dst, 0);
386	}
387
388	static char absolutify(char file)
389	{
390	static int inited = 0;
391	static char cwd[1024];
392
393	if(*file != '/') {
394	if(!inited) {
395	getcwd(cwd, sizeof(cwd));
396	inited = 1;
397	}
398	return(sprintf2("%s/%s", cwd, file));
399	}
400	return(sstrdup(file));
401	}
402
403	/* Mostly copied from callcgi. */
404	static void mkcgienv(struct hthead req, struct charbuf dst)
405	{
406	int i;
53d666ca	407	char url, pi, tmp, qp, h, p;
f89ce57a FT	408
	409	bufaddenv(dst, "SERVER_SOFTWARE", "ashd/%s", VERSION);
	410	bufaddenv(dst, "GATEWAY_INTERFACE", "CGI/1.1");
	411	bufaddenv(dst, "SCGI", "1");
	412	bufaddenv(dst, "SERVER_PROTOCOL", "%s", req->ver);
	413	bufaddenv(dst, "REQUEST_METHOD", "%s", req->method);
	414	bufaddenv(dst, "REQUEST_URI", "%s", req->url);
f89ce57a FT	415	url = sstrdup(req->url);
	416	if((qp = strchr(url, '?')) != NULL)
	417	*(qp++) = 0;
	418	/* XXX: This is an ugly hack (I think), but though I can think of
	419	* several alternatives, none seem to be better. */
2d65add0 FT	420	if(*req->rest && (strlen(url) >= strlen(req->rest)) &&
2d65add0 FT	421	!strcmp(req->rest, url + strlen(url) - strlen(req->rest))) {
53d666ca FT	422	url[strlen(url) - strlen(req->rest)] = 0;
	423	}
	424	if((pi = unquoteurl(req->rest)) == NULL)
	425	pi = sstrdup(req->rest);
	426	if(!strcmp(url, "/")) {
	427	/* This seems to be normal CGI behavior, but see callcgi.c for
	428	* details. */
	429	url[0] = 0;
	430	pi = sprintf2("/%s", tmp = pi);
	431	free(tmp);
f89ce57a	432	}
53d666ca FT	433	bufaddenv(dst, "PATH_INFO", pi);
53d666ca FT	434	bufaddenv(dst, "SCRIPT_NAME", url);
f89ce57a	435	bufaddenv(dst, "QUERY_STRING", "%s", qp?qp:"");
53d666ca	436	free(pi);
b77076c4	437	free(url);
f89ce57a FT	438	if((h = getheader(req, "Host")) != NULL)
f89ce57a FT	439	bufaddenv(dst, "SERVER_NAME", "%s", h);
1af656d2 FT	440	if((h = getheader(req, "X-Ash-Server-Address")) != NULL)
1af656d2 FT	441	bufaddenv(dst, "SERVER_ADDR", "%s", h);
f89ce57a FT	442	if((h = getheader(req, "X-Ash-Server-Port")) != NULL)
f89ce57a FT	443	bufaddenv(dst, "SERVER_PORT", "%s", h);
381f9919 FT	444	if((h = getheader(req, "X-Ash-Remote-User")) != NULL)
381f9919 FT	445	bufaddenv(dst, "REMOTE_USER", "%s", h);
9230295c	446	if(((h = getheader(req, "X-Ash-Protocol")) != NULL) && !strcmp(h, "https"))
f89ce57a FT	447	bufaddenv(dst, "HTTPS", "on");
	448	if((h = getheader(req, "X-Ash-Address")) != NULL)
	449	bufaddenv(dst, "REMOTE_ADDR", "%s", h);
1af656d2 FT	450	if((h = getheader(req, "X-Ash-Port")) != NULL)
1af656d2 FT	451	bufaddenv(dst, "REMOTE_PORT", "%s", h);
f89ce57a FT	452	if((h = getheader(req, "Content-Type")) != NULL)
	453	bufaddenv(dst, "CONTENT_TYPE", "%s", h);
	454	if((h = getheader(req, "Content-Length")) != NULL)
	455	bufaddenv(dst, "CONTENT_LENGTH", "%s", h);
	456	else
	457	bufaddenv(dst, "CONTENT_LENGTH", "0");
e25bf4f9 FT	458	if((h = getheader(req, "X-Ash-File")) != NULL) {
	459	h = absolutify(h);
	460	bufaddenv(dst, "SCRIPT_FILENAME", "%s", h);
	461	free(h);
	462	}
f89ce57a	463	for(i = 0; i < req->noheaders; i++) {
02cb2a3d	464	h = sprintf2("HTTP_%s", req->headers[i][0]);
f89ce57a FT	465	for(p = h; *p; p++) {
	466	if(isalnum(*p))
	467	p = toupper(p);
	468	else
	469	*p = '_';
	470	}
	471	bufcatstr2(*dst, h);
	472	free(h);
	473	bufcatstr2(*dst, req->headers[i][1]);
	474	}
	475	}
	476
f89ce57a FT	477	static struct hthead parseresp(FILE in)
	478	{
	479	struct hthead *resp;
	480	char st, p;
	481
	482	omalloc(resp);
	483	resp->ver = sstrdup("HTTP/1.1");
	484	if(parseheaders(resp, in)) {
	485	freehthead(resp);
	486	return(NULL);
	487	}
	488	if((st = getheader(resp, "Status")) != NULL) {
	489	if((p = strchr(st, ' ')) != NULL) {
	490	*(p++) = 0;
	491	resp->code = atoi(st);
	492	resp->msg = sstrdup(p);
	493	} else {
	494	resp->code = atoi(st);
62e76c42	495	resp->msg = sstrdup(httpdefstatus(resp->code));
f89ce57a FT	496	}
	497	headrmheader(resp, "Status");
	498	} else if(getheader(resp, "Location")) {
	499	resp->code = 303;
	500	resp->msg = sstrdup("See Other");
	501	} else {
	502	resp->code = 200;
	503	resp->msg = sstrdup("OK");
	504	}
	505	return(resp);
	506	}
	507
	508	static void serve(struct muth *muth, va_list args)
	509	{
	510	vavar(struct hthead *, req);
	511	vavar(int, fd);
	512	vavar(int, sfd);
	513	FILE is, os;
	514	struct charbuf head;
	515	struct hthead *resp;
	516
	517	sfd = reconn();
	518	is = mtstdopen(fd, 1, 60, "r+");
	519	os = mtstdopen(sfd, 1, 600, "r+");
	520
	521	bufinit(head);
	522	mkcgienv(req, &head);
	523	fprintf(os, "%zi:", head.d);
	524	fwrite(head.b, head.d, 1, os);
	525	fputc(',', os);
	526	buffree(head);
	527	if(passdata(is, os) < 0)
	528	goto out;
	529
	530	if((resp = parseresp(os)) == NULL)
	531	goto out;
	532	writeresp(is, resp);
	533	freehthead(resp);
	534	fputc('\n', is);
	535	if(passdata(os, is) < 0)
	536	goto out;
	537
	538	out:
	539	freehthead(req);
	540	fclose(is);
	541	fclose(os);
	542	}
	543
	544	static void listenloop(struct muth *muth, va_list args)
	545	{
	546	vavar(int, lfd);
	547	int fd;
	548	struct hthead *req;
	549
	550	while(1) {
	551	block(0, EV_READ, 0);
	552	if((fd = recvreq(lfd, &req)) < 0) {
	553	if(errno != 0)
	554	flog(LOG_ERR, "recvreq: %s", strerror(errno));
	555	break;
	556	}
	557	mustart(serve, req, fd);
	558	}
	559	}
560
fd735432 FT	561	static void sigign(int sig)
	562	{
	563	}
	564
9c86e336 FT	565	static void sigexit(int sig)
9c86e336 FT	566	{
254eb937	567	shutdown(0, SHUT_RDWR);
9c86e336 FT	568	}
9c86e336 FT	569
f89ce57a FT	570	static void usage(FILE *out)
f89ce57a FT	571	{
425eccf6	572	fprintf(out, "usage: callscgi [-h] [-N RETRIES] [-i ID] [-u UNIX-PATH] [-t [HOST:]TCP-PORT] [PROGRAM [ARGS...]]\n");
f89ce57a FT	573	}
	574
	575	int main(int argc, char **argv)
	576	{
	577	int c;
	578
	579	while((c = getopt(argc, argv, "+hN:i:u:t:")) >= 0) {
	580	switch(c) {
	581	case 'h':
	582	usage(stdout);
	583	exit(0);
	584	case 'N':
	585	nolisten = atoi(optarg);
	586	break;
	587	case 'i':
	588	sockid = optarg;
	589	break;
	590	case 'u':
	591	unspec = optarg;
	592	break;
	593	case 't':
	594	inspec = optarg;
	595	break;
	596	default:
	597	usage(stderr);
	598	exit(1);
	599	}
	600	}
	601	progspec = argv + optind;
	602	if(((sockid != NULL) + (unspec != NULL) + (inspec != NULL)) > 1) {
425eccf6	603	flog(LOG_ERR, "callscgi: at most one of -i, -u or -t may be given");
f89ce57a FT	604	exit(1);
	605	}
	606	signal(SIGCHLD, SIG_IGN);
fd735432	607	signal(SIGPIPE, sigign);
9c86e336 FT	608	signal(SIGINT, sigexit);
9c86e336 FT	609	signal(SIGTERM, sigexit);
f89ce57a FT	610	mustart(listenloop, 0);
	611	atexit(killcuraddr);
	612	ioloop();
	613	return(0);
	614	}