[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 <sys/signal.h>
#include <errno.h>

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <utils.h>
#include <req.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, "servescgi: 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, *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);
    if(*req->rest)
	bufaddenv(dst, "PATH_INFO", "/%s", req->rest);
    else
	bufaddenv(dst, "PATH_INFO", "");
    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) - 1] == '/')) {
	bufaddenv(dst, "SCRIPT_NAME", "%.*s", (int)(strlen(url) - strlen(req->rest) - 1), url);
    } else {
	bufaddenv(dst, "SCRIPT_NAME", "%s", url);
    }
    bufaddenv(dst, "QUERY_STRING", "%s", qp?qp:"");
    if((h = getheader(req, "Host")) != NULL)
	bufaddenv(dst, "SERVER_NAME", "%s", h);
    if((h = getheader(req, "X-Ash-Server-Port")) != NULL)
	bufaddenv(dst, "SERVER_PORT", "%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, "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)
	bufaddenv(dst, "SCRIPT_FILENAME", "%s", absolutify(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 char *defstatus(int code)
{
    if(code == 200)
	return("OK");
    else if(code == 201)
	return("Created");
    else if(code == 202)
	return("Accepted");
    else if(code == 204)
	return("No Content");
    else if(code == 300)
	return("Multiple Choices");
    else if(code == 301)
	return("Moved Permanently");
    else if(code == 302)
	return("Found");
    else if(code == 303)
	return("See Other");
    else if(code == 304)
	return("Not Modified");
    else if(code == 307)
	return("Moved Temporarily");
    else if(code == 400)
	return("Bad Request");
    else if(code == 401)
	return("Unauthorized");
    else if(code == 403)
	return("Forbidden");
    else if(code == 404)
	return("Not Found");
    else if(code == 500)
	return("Internal Server Error");
    else if(code == 501)
	return("Not Implemented");
    else if(code == 503)
	return("Service Unavailable");
    else
	return("Unknown status");
}

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(defstatus(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 sigexit(int sig)
{
    exit(0);
}

static void usage(FILE *out)
{
    fprintf(out, "usage: servescgi [-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, "servescgi: at most one of -i, -u or -t may be given");
	exit(1);
    }
    signal(SIGCHLD, SIG_IGN);
    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>
	35	#include <sys/signal.h>
	36	#include <errno.h>
	37
	38	#ifdef HAVE_CONFIG_H
	39	#include <config.h>
	40	#endif
	41	#include <utils.h>
	42	#include <req.h>
	43	#include <log.h>
	44	#include <mt.h>
	45	#include <mtio.h>
	46
	47	static char **progspec;
	48	static char sockid, unspec, *inspec;
	49	static int nolisten;
	50	static struct sockaddr *curaddr;
	51	static size_t caddrlen;
	52	static int cafamily, isanon;
	53	static pid_t child;
	54
	55	static struct addrinfo *resolv(int flags)
	56	{
	57	int ret;
	58	struct addrinfo *ai, h;
	59	char name, srv, *p;
	60
	61	if((p = strchr(inspec, ':')) != NULL) {
	62	name = smalloc(p - inspec + 1);
	63	memcpy(name, inspec, p - inspec);
	64	name[p - inspec] = 0;
65	srv = p + 1;
66	} else {
67	name = sstrdup("localhost");
68	srv = inspec;
69	}
70	memset(&h, 0, sizeof(h));
71	h.ai_family = AF_UNSPEC;
72	h.ai_socktype = SOCK_STREAM;
73	h.ai_flags = flags;
74	ret = getaddrinfo(name, srv, &h, &ai);
75	free(name);
76	if(ret != 0) {
77	flog(LOG_ERR, "could not resolve TCP specification `%s': %s", inspec, gai_strerror(ret));
78	exit(1);
79	}
80	return(ai);
81	}
82
83	static char mksockid(char sockid)
84	{
85	char *home;
86
87	home = getenv("HOME");
88	if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
89	return(sprintf3("%s/.ashd/sockets/scgi-p-%s", home, sockid));
90	return(sprintf3("/tmp/scgi-%i-%s", getuid(), sockid));
91	}
92
93	static char *mkanonid(void)
94	{
95	char *home;
96	char *tmpl;
97	int fd;
98
99	home = getenv("HOME");
100	if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
1376c0cd	101	tmpl = sprintf2("%s/.ashd/sockets/scgi-a-XXXXXX", home);
f89ce57a FT	102	else
	103	tmpl = sprintf2("/tmp/scgi-a-%i-XXXXXX", getuid());
	104	if((fd = mkstemp(tmpl)) < 0) {
	105	flog(LOG_ERR, "could not create anonymous socket `%s': %s", tmpl, strerror(errno));
	106	exit(1);
	107	}
1376c0cd	108	close(fd);
f89ce57a FT	109	unlink(tmpl);
	110	return(tmpl);
	111	}
	112
	113	static void startlisten(void)
	114	{
	115	int i, fd;
	116	struct addrinfo ai, cai;
	117	char *unpath;
	118	struct sockaddr_un unm;
	119	char *aname;
	120
	121	isanon = 0;
	122	if(inspec != NULL) {
	123	fd = -1;
	124	for(cai = ai = resolv(AI_PASSIVE); cai != NULL; cai = cai->ai_next) {
	125	if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
	126	continue;
	127	if(bind(fd, cai->ai_addr, cai->ai_addrlen)) {
	128	close(fd);
	129	fd = -1;
	130	continue;
	131	}
	132	if(listen(fd, 128)) {
	133	close(fd);
	134	fd = -1;
	135	continue;
	136	}
	137	break;
	138	}
	139	freeaddrinfo(ai);
	140	if(fd < 0) {
	141	flog(LOG_ERR, "could not bind to specified TCP address: %s", strerror(errno));
	142	exit(1);
	143	}
	144	} else if((unspec != NULL) \|\| (sockid != NULL)) {
	145	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	146	flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	147	exit(1);
	148	}
	149	if(unspec != NULL)
	150	unpath = unspec;
	151	else
	152	unpath = mksockid(sockid);
	153	unlink(unpath);
	154	unm.sun_family = AF_UNIX;
	155	strcpy(unm.sun_path, unpath);
	156	if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
	157	flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
	158	exit(1);
	159	}
	160	if(listen(fd, 128)) {
	161	flog(LOG_ERR, "listen: %s", strerror(errno));
	162	exit(1);
	163	}
	164	} else {
	165	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	166	flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	167	exit(1);
	168	}
	169	memset(&unm, 0, sizeof(unm));
	170	aname = mkanonid();
	171	unm.sun_family = AF_UNIX;
	172	strcpy(unm.sun_path, aname);
173	free(aname);
174	if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
175	flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
176	exit(1);
177	}
178	if(listen(fd, 128)) {
179	flog(LOG_ERR, "listen: %s", strerror(errno));
180	exit(1);
181	}
182
183	curaddr = smalloc(caddrlen = sizeof(unm));
184	memcpy(curaddr, &unm, sizeof(unm));
185	cafamily = AF_UNIX;
186	isanon = 1;
187	}
188	if((child = fork()) < 0) {
189	flog(LOG_ERR, "could not fork: %s", strerror(errno));
190	exit(1);
191	}
192	if(child == 0) {
193	dup2(fd, 0);
194	for(i = 3; i < FD_SETSIZE; i++)
195	close(i);
196	execvp(*progspec, progspec);
7b9c1cff	197	flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
f89ce57a FT	198	exit(127);
	199	}
	200	close(fd);
	201	}
	202
	203	static void startnolisten(void)
	204	{
02cb2a3d	205	int i, fd;
f89ce57a FT	206
	207	if((child = fork()) < 0) {
	208	flog(LOG_ERR, "could not fork: %s", strerror(errno));
	209	exit(1);
	210	}
	211	if(child == 0) {
	212	for(i = 3; i < FD_SETSIZE; i++)
	213	close(i);
02cb2a3d FT	214	if((fd = open("/dev/null", O_RDONLY)) < 0) {
	215	flog(LOG_ERR, "/dev/null: %s", strerror(errno));
	216	exit(127);
	217	}
	218	dup2(fd, 0);
	219	close(fd);
f89ce57a	220	execvp(*progspec, progspec);
7b9c1cff	221	flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
f89ce57a FT	222	exit(127);
	223	}
	224	}
	225
	226	static int sconnect(void)
	227	{
	228	int fd;
	229	int err;
	230	socklen_t errlen;
	231
	232	fd = socket(cafamily, SOCK_STREAM, 0);
	233	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) \| O_NONBLOCK);
	234	while(1) {
	235	if(connect(fd, curaddr, caddrlen)) {
	236	if(errno == EINPROGRESS) {
	237	block(fd, EV_WRITE, 30);
	238	errlen = sizeof(err);
	239	if(getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errlen) \|\| ((errno = err) != 0)) {
	240	close(fd);
	241	return(-1);
	242	}
	243	return(fd);
	244	}
	245	close(fd);
	246	return(-1);
	247	}
	248	return(fd);
	249	}
	250	}
	251
	252	static int econnect(void)
	253	{
	254	int fd;
	255	struct addrinfo ai, cai;
	256	int tries;
	257	char *unpath;
	258	struct sockaddr_un unm;
	259
	260	tries = 0;
	261	retry:
	262	if(inspec != NULL) {
	263	fd = -1;
	264	for(cai = ai = resolv(0); cai != NULL; cai = cai->ai_next) {
	265	if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
	266	continue;
	267	if(connect(fd, cai->ai_addr, cai->ai_addrlen)) {
	268	close(fd);
	269	fd = -1;
	270	continue;
	271	}
	272	break;
	273	}
f89ce57a	274	if(fd < 0) {
02cb2a3d FT	275	if(tries++ < nolisten) {
	276	sleep(1);
	277	goto retry;
	278	}
f89ce57a FT	279	flog(LOG_ERR, "could not connect to specified TCP address: %s", strerror(errno));
	280	exit(1);
	281	}
	282	curaddr = smalloc(caddrlen = cai->ai_addrlen);
	283	memcpy(curaddr, cai->ai_addr, caddrlen);
	284	cafamily = cai->ai_family;
	285	isanon = 0;
	286	freeaddrinfo(ai);
	287	return(fd);
	288	} else if((unspec != NULL) \|\| (sockid != NULL)) {
	289	if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	290	flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
	291	exit(1);
	292	}
	293	if(unspec != NULL)
	294	unpath = unspec;
	295	else
	296	unpath = mksockid(sockid);
	297	unlink(unpath);
	298	unm.sun_family = AF_UNIX;
	299	strcpy(unm.sun_path, unpath);
	300	if(connect(fd, (struct sockaddr *)&unm, sizeof(unm))) {
	301	close(fd);
	302	if(tries++ < nolisten) {
	303	sleep(1);
	304	goto retry;
	305	}
	306	flog(LOG_ERR, "could not connect to Unix socket `%s': %s", unspec, strerror(errno));
	307	exit(1);
	308	}
	309	curaddr = smalloc(caddrlen = sizeof(unm));
	310	memcpy(curaddr, &unm, sizeof(unm));
	311	cafamily = AF_UNIX;
	312	isanon = 0;
	313	return(fd);
	314	} else {
	315	flog(LOG_ERR, "servescgi: cannot use an anonymous socket without a program to start");
	316	exit(1);
	317	}
	318	}
	319
	320	static int startconn(void)
	321	{
	322	if(*progspec) {
	323	if(nolisten == 0)
	324	startlisten();
	325	else
	326	startnolisten();
	327	}
	328	if(curaddr != NULL)
	329	return(sconnect());
	330	return(econnect());
	331	}
	332
	333	static void killcuraddr(void)
	334	{
	335	if(curaddr == NULL)
	336	return;
	337	if(isanon) {
	338	unlink(((struct sockaddr_un *)curaddr)->sun_path);
	339	if(child > 0)
	340	kill(child, SIGTERM);
	341	}
	342	free(curaddr);
343	curaddr = NULL;
344	}
345
346	static int reconn(void)
347	{
348	int fd;
349
350	if(curaddr != NULL) {
351	if((fd = sconnect()) >= 0)
352	return(fd);
353	killcuraddr();
354	}
355	return(startconn());
356	}
357
358	static off_t passdata(FILE in, FILE out)
359	{
360	size_t read;
361	off_t total;
362	char buf[8192];
363
364	total = 0;
365	while(!feof(in)) {
366	read = fread(buf, 1, sizeof(buf), in);
367	if(ferror(in))
368	return(-1);
369	if(fwrite(buf, 1, read, out) != read)
370	return(-1);
371	total += read;
372	}
373	return(total);
374	}
375
376	static void bufaddenv(struct charbuf dst, char name, char *fmt, ...)
377	{
378	va_list args;
379
380	bufcatstr2(*dst, name);
381	va_start(args, fmt);
382	bvprintf(dst, fmt, args);
383	va_end(args);
384	bufadd(*dst, 0);
385	}
386
387	static char absolutify(char file)
388	{
389	static int inited = 0;
390	static char cwd[1024];
391
392	if(*file != '/') {
393	if(!inited) {
394	getcwd(cwd, sizeof(cwd));
395	inited = 1;
396	}
397	return(sprintf2("%s/%s", cwd, file));
398	}
399	return(sstrdup(file));
400	}
401
402	/* Mostly copied from callcgi. */
403	static void mkcgienv(struct hthead req, struct charbuf dst)
404	{
405	int i;
406	char url, qp, h, p;
407
408	bufaddenv(dst, "SERVER_SOFTWARE", "ashd/%s", VERSION);
409	bufaddenv(dst, "GATEWAY_INTERFACE", "CGI/1.1");
410	bufaddenv(dst, "SCGI", "1");
411	bufaddenv(dst, "SERVER_PROTOCOL", "%s", req->ver);
412	bufaddenv(dst, "REQUEST_METHOD", "%s", req->method);
413	bufaddenv(dst, "REQUEST_URI", "%s", req->url);
414	if(*req->rest)
415	bufaddenv(dst, "PATH_INFO", "/%s", req->rest);
416	else
417	bufaddenv(dst, "PATH_INFO", "");
418	url = sstrdup(req->url);
419	if((qp = strchr(url, '?')) != NULL)
420	*(qp++) = 0;
421	/* XXX: This is an ugly hack (I think), but though I can think of
422	* several alternatives, none seem to be better. */
423	if(*req->rest && (strlen(url) > strlen(req->rest)) &&
424	!strcmp(req->rest, url + strlen(url) - strlen(req->rest)) &&
425	(url[strlen(url) - strlen(req->rest) - 1] == '/')) {
426	bufaddenv(dst, "SCRIPT_NAME", "%.*s", (int)(strlen(url) - strlen(req->rest) - 1), url);
427	} else {
428	bufaddenv(dst, "SCRIPT_NAME", "%s", url);
429	}
430	bufaddenv(dst, "QUERY_STRING", "%s", qp?qp:"");
431	if((h = getheader(req, "Host")) != NULL)
432	bufaddenv(dst, "SERVER_NAME", "%s", h);
433	if((h = getheader(req, "X-Ash-Server-Port")) != NULL)
434	bufaddenv(dst, "SERVER_PORT", "%s", h);
9230295c	435	if(((h = getheader(req, "X-Ash-Protocol")) != NULL) && !strcmp(h, "https"))
f89ce57a FT	436	bufaddenv(dst, "HTTPS", "on");
	437	if((h = getheader(req, "X-Ash-Address")) != NULL)
	438	bufaddenv(dst, "REMOTE_ADDR", "%s", h);
	439	if((h = getheader(req, "Content-Type")) != NULL)
	440	bufaddenv(dst, "CONTENT_TYPE", "%s", h);
	441	if((h = getheader(req, "Content-Length")) != NULL)
	442	bufaddenv(dst, "CONTENT_LENGTH", "%s", h);
	443	else
	444	bufaddenv(dst, "CONTENT_LENGTH", "0");
	445	if((h = getheader(req, "X-Ash-File")) != NULL)
	446	bufaddenv(dst, "SCRIPT_FILENAME", "%s", absolutify(h));
	447	for(i = 0; i < req->noheaders; i++) {
02cb2a3d	448	h = sprintf2("HTTP_%s", req->headers[i][0]);
f89ce57a FT	449	for(p = h; *p; p++) {
	450	if(isalnum(*p))
	451	p = toupper(p);
	452	else
	453	*p = '_';
	454	}
	455	bufcatstr2(*dst, h);
	456	free(h);
	457	bufcatstr2(*dst, req->headers[i][1]);
	458	}
	459	}
	460
	461	static char *defstatus(int code)
	462	{
	463	if(code == 200)
	464	return("OK");
	465	else if(code == 201)
	466	return("Created");
	467	else if(code == 202)
	468	return("Accepted");
	469	else if(code == 204)
	470	return("No Content");
	471	else if(code == 300)
	472	return("Multiple Choices");
	473	else if(code == 301)
	474	return("Moved Permanently");
	475	else if(code == 302)
	476	return("Found");
	477	else if(code == 303)
	478	return("See Other");
	479	else if(code == 304)
	480	return("Not Modified");
	481	else if(code == 307)
	482	return("Moved Temporarily");
	483	else if(code == 400)
	484	return("Bad Request");
	485	else if(code == 401)
	486	return("Unauthorized");
	487	else if(code == 403)
	488	return("Forbidden");
	489	else if(code == 404)
	490	return("Not Found");
	491	else if(code == 500)
	492	return("Internal Server Error");
	493	else if(code == 501)
	494	return("Not Implemented");
	495	else if(code == 503)
	496	return("Service Unavailable");
	497	else
	498	return("Unknown status");
	499	}
	500
	501	static struct hthead parseresp(FILE in)
	502	{
	503	struct hthead *resp;
	504	char st, p;
	505
	506	omalloc(resp);
	507	resp->ver = sstrdup("HTTP/1.1");
	508	if(parseheaders(resp, in)) {
	509	freehthead(resp);
	510	return(NULL);
	511	}
	512	if((st = getheader(resp, "Status")) != NULL) {
513	if((p = strchr(st, ' ')) != NULL) {
514	*(p++) = 0;
515	resp->code = atoi(st);
516	resp->msg = sstrdup(p);
517	} else {
518	resp->code = atoi(st);
519	resp->msg = sstrdup(defstatus(resp->code));
520	}
521	headrmheader(resp, "Status");
522	} else if(getheader(resp, "Location")) {
523	resp->code = 303;
524	resp->msg = sstrdup("See Other");
525	} else {
526	resp->code = 200;
527	resp->msg = sstrdup("OK");
528	}
529	return(resp);
530	}
531
532	static void serve(struct muth *muth, va_list args)
533	{
534	vavar(struct hthead *, req);
535	vavar(int, fd);
536	vavar(int, sfd);
537	FILE is, os;
538	struct charbuf head;
539	struct hthead *resp;
540
541	sfd = reconn();
542	is = mtstdopen(fd, 1, 60, "r+");
543	os = mtstdopen(sfd, 1, 600, "r+");
544
545	bufinit(head);
546	mkcgienv(req, &head);
547	fprintf(os, "%zi:", head.d);
548	fwrite(head.b, head.d, 1, os);
549	fputc(',', os);
550	buffree(head);
551	if(passdata(is, os) < 0)
552	goto out;
553
554	if((resp = parseresp(os)) == NULL)
555	goto out;
556	writeresp(is, resp);
557	freehthead(resp);
558	fputc('\n', is);
559	if(passdata(os, is) < 0)
560	goto out;
561
562	out:
563	freehthead(req);
564	fclose(is);
565	fclose(os);
566	}
567
568	static void listenloop(struct muth *muth, va_list args)
569	{
570	vavar(int, lfd);
571	int fd;
572	struct hthead *req;
573
574	while(1) {
575	block(0, EV_READ, 0);
576	if((fd = recvreq(lfd, &req)) < 0) {
577	if(errno != 0)
578	flog(LOG_ERR, "recvreq: %s", strerror(errno));
579	break;
580	}
581	mustart(serve, req, fd);
582	}
583	}
584
9c86e336 FT	585	static void sigexit(int sig)
	586	{
	587	exit(0);
	588	}
	589
f89ce57a FT	590	static void usage(FILE *out)
	591	{
	592	fprintf(out, "usage: servescgi [-h] [-N RETRIES] [-i ID] [-u UNIX-PATH] [-t [HOST:]TCP-PORT] [PROGRAM [ARGS...]]\n");
	593	}
	594
	595	int main(int argc, char **argv)
	596	{
	597	int c;
	598
	599	while((c = getopt(argc, argv, "+hN:i:u:t:")) >= 0) {
	600	switch(c) {
	601	case 'h':
	602	usage(stdout);
	603	exit(0);
	604	case 'N':
	605	nolisten = atoi(optarg);
	606	break;
	607	case 'i':
	608	sockid = optarg;
	609	break;
	610	case 'u':
	611	unspec = optarg;
	612	break;
	613	case 't':
	614	inspec = optarg;
	615	break;
	616	default:
	617	usage(stderr);
	618	exit(1);
	619	}
	620	}
	621	progspec = argv + optind;
	622	if(((sockid != NULL) + (unspec != NULL) + (inspec != NULL)) > 1) {
	623	flog(LOG_ERR, "servescgi: at most one of -i, -u or -t may be given");
	624	exit(1);
	625	}
	626	signal(SIGCHLD, SIG_IGN);
9c86e336 FT	627	signal(SIGINT, sigexit);
9c86e336 FT	628	signal(SIGTERM, sigexit);
f89ce57a FT	629	mustart(listenloop, 0);
	630	atexit(killcuraddr);
	631	ioloop();
	632	return(0);
	633	}