NetBSD/libexec/httpd/cgi-bozo.c

482 lines
13 KiB
C

/* $NetBSD: cgi-bozo.c,v 1.14 2009/05/23 02:26:03 mrg Exp $ */
/* $eterna: cgi-bozo.c,v 1.32 2009/05/22 21:51:38 mrg Exp $ */
/*
* Copyright (c) 1997-2009 Matthew R. Green
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer and
* dedication in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/* this code implements CGI/1.2 for bozohttpd */
#ifndef NO_CGIBIN_SUPPORT
#include <sys/param.h>
#include <sys/socket.h>
#include <ctype.h>
#include <errno.h>
#include <paths.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <netinet/in.h>
#include "bozohttpd.h"
#define CGIBIN_PREFIX "cgi-bin/"
#define CGIBIN_PREFIX_LEN (sizeof(CGIBIN_PREFIX)-1)
static char *cgibin; /* cgi-bin directory */
static int Cflag; /* added a cgi handler, always process_cgi() */
static const char * content_cgihandler(http_req *, const char *);
static void finish_cgi_output(http_req *request, int, int);
static int parse_header(const char *, ssize_t, char **, char **);
static void append_index_html(char **);
void
set_cgibin(char *path)
{
cgibin = path;
debug((DEBUG_OBESE, "cgibin (cgi-bin directory) is %s", cgibin));
}
/* help build up the environ pointer */
void
spsetenv(const char *env, const char *val, char **envp)
{
char *s1 = bozomalloc(strlen(env) + strlen(val) + 2);
strcpy(s1, env);
strcat(s1, "=");
strcat(s1, val);
debug((DEBUG_OBESE, "spsetenv: %s", s1));
*envp = s1;
}
/*
* Checks if the request has asked for a cgi-bin. Should only be called if
* cgibin is set. If it starts CGIBIN_PREFIX or has a ncontent handler,
* process the cgi, otherwise just return. Returns 0 if it did not handle
* the request.
*/
int
process_cgi(http_req *request)
{
char buf[WRSZ];
struct headers *headp;
const char *type, *clen, *info, *cgihandler;
char *query, *s, *t, *path, *env, *command, *file, *url;
char **envp, **curenvp, *argv[4];
size_t len;
ssize_t rbytes;
pid_t pid;
int envpsize, ix, nph;
int sv[2];
if (!cgibin && !Cflag)
return 0;
asprintf(&file, "/%s", request->hr_file);
if (file == NULL)
return 0;
if (request->hr_query && strlen(request->hr_query))
query = bozostrdup(request->hr_query);
else
query = NULL;
asprintf(&url, "%s%s%s", file, query ? "?" : "", query ? query : "");
if (url == NULL)
goto out;
debug((DEBUG_NORMAL, "process_cgi: url `%s'", url));
path = NULL;
envp = NULL;
cgihandler = NULL;
command = NULL;
info = NULL;
len = strlen(url);
if (auth_check(request, url + 1))
goto out;
if (!cgibin || strncmp(url + 1, CGIBIN_PREFIX, CGIBIN_PREFIX_LEN) != 0) {
cgihandler = content_cgihandler(request, file + 1);
if (cgihandler == NULL) {
debug((DEBUG_FAT, "process_cgi: no handler, returning"));
goto out;
}
if (len == 0 || file[len - 1] == '/')
append_index_html(&file);
debug((DEBUG_NORMAL, "process_cgi: cgihandler `%s'",
cgihandler));
} else if (len - 1 == CGIBIN_PREFIX_LEN) /* url is "/cgi-bin/" */
append_index_html(&file);
ix = 0;
if (cgihandler) {
command = file + 1;
path = bozostrdup(cgihandler);
argv[ix++] = path;
/* argv[] = [ path, command, query, NULL ] */
} else {
command = file + CGIBIN_PREFIX_LEN + 1;
if ((s = strchr(command, '/')) != NULL) {
info = bozostrdup(s);
*s = '\0';
}
path = bozomalloc(strlen(cgibin) + 1 + strlen(command) + 1);
strcpy(path, cgibin);
strcat(path, "/");
strcat(path, command);
/* argv[] = [ command, query, NULL ] */
}
argv[ix++] = command;
argv[ix++] = query;
argv[ix++] = NULL;
nph = strncmp(command, "nph-", 4) == 0;
type = request->hr_content_type;
clen = request->hr_content_length;
envpsize = 13 + request->hr_nheaders +
(info && *info ? 1 : 0) +
(query && *query ? 1 : 0) +
(type && *type ? 1 : 0) +
(clen && *clen ? 1 : 0) +
(request->hr_remotehost && *request->hr_remotehost ? 1 : 0) +
(request->hr_remoteaddr && *request->hr_remoteaddr ? 1 : 0) +
auth_cgi_count(request) +
(request->hr_serverport && *request->hr_serverport ? 1 : 0);
debug((DEBUG_FAT,
"process_cgi: path `%s' cmd `%s' info `%s' query `%s' nph `%d' envpsize `%d'",
path, command, strornull(info), strornull(query), nph, envpsize));
envp = bozomalloc(sizeof(*envp) * envpsize);
for (ix = 0; ix < envpsize; ix++)
envp[ix] = NULL;
curenvp = envp;
SIMPLEQ_FOREACH(headp, &request->hr_headers, h_next) {
const char *s2;
env = bozomalloc(6 + strlen(headp->h_header) + 1 +
strlen(headp->h_value));
t = env;
strcpy(t, "HTTP_");
t += strlen(t);
for (s2 = headp->h_header; *s2; t++, s2++)
if (islower((u_int)*s2))
*t = toupper((u_int)*s2);
else if (*s2 == '-')
*t = '_';
else
*t = *s2;
*t = '\0';
debug((DEBUG_OBESE, "setting header %s as %s = %s",
headp->h_header, env, headp->h_value));
spsetenv(env, headp->h_value, curenvp++);
free(env);
}
#ifndef _PATH_DEFPATH
#define _PATH_DEFPATH "/usr/bin:/bin"
#endif
spsetenv("PATH", _PATH_DEFPATH, curenvp++);
spsetenv("IFS", " \t\n", curenvp++);
spsetenv("SERVER_NAME", myname, curenvp++);
spsetenv("GATEWAY_INTERFACE", "CGI/1.1", curenvp++);
spsetenv("SERVER_PROTOCOL", request->hr_proto, curenvp++);
spsetenv("REQUEST_METHOD", request->hr_methodstr, curenvp++);
spsetenv("SCRIPT_NAME", file, curenvp++);
spsetenv("SCRIPT_FILENAME", file + 1, curenvp++);
spsetenv("SERVER_SOFTWARE", server_software, curenvp++);
spsetenv("REQUEST_URI", request->hr_file, curenvp++);
spsetenv("DATE_GMT", http_date(), curenvp++);
if (query && *query)
spsetenv("QUERY_STRING", query, curenvp++);
if (info && *info)
spsetenv("PATH_INFO", info, curenvp++);
if (type && *type)
spsetenv("CONTENT_TYPE", type, curenvp++);
if (clen && *clen)
spsetenv("CONTENT_LENGTH", clen, curenvp++);
if (request->hr_serverport && *request->hr_serverport)
spsetenv("SERVER_PORT", request->hr_serverport, curenvp++);
if (request->hr_remotehost && *request->hr_remotehost)
spsetenv("REMOTE_HOST", request->hr_remotehost, curenvp++);
if (request->hr_remoteaddr && *request->hr_remoteaddr)
spsetenv("REMOTE_ADDR", request->hr_remoteaddr, curenvp++);
auth_cgi_setenv(request, &curenvp);
free(file);
free(url);
debug((DEBUG_FAT, "process_cgi: going exec %s, %s %s %s",
path, argv[0], strornull(argv[1]), strornull(argv[2])));
if (-1 == socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, sv))
error(1, "child socketpair failed: %s", strerror(errno));
/*
* We create 2 procs: one to become the CGI, one read from
* the CGI and output to the network, and this parent will
* continue reading from the network and writing to the
* CGI procsss.
*/
switch (fork()) {
case -1: /* eep, failure */
error(1, "child fork failed: %s", strerror(errno));
case 0:
close(sv[0]);
dup2(sv[1], STDIN_FILENO);
dup2(sv[1], STDOUT_FILENO);
close(2);
close(sv[1]);
closelog();
daemon_closefds();
if (-1 == execve(path, argv, envp))
error(1, "child exec failed: %s: %s",
path, strerror(errno));
/* NOT REACHED */
error(1, "child execve returned?!");
}
close(sv[1]);
/* parent: read from stdin (bozoread()) write to sv[0] */
/* child: read from sv[0] (bozowrite()) write to stdout */
pid = fork();
if (pid == -1)
error(1, "io child fork failed: %s", strerror(errno));
else if (pid == 0) {
/* child reader/writer */
close(STDIN_FILENO);
finish_cgi_output(request, sv[0], nph);
/* if we're done output, our parent is useless... */
kill(getppid(), SIGKILL);
debug((DEBUG_FAT, "done processing cgi output"));
_exit(0);
}
close(STDOUT_FILENO);
/* XXX we should have some goo that times us out
*/
while ((rbytes = bozoread(STDIN_FILENO, buf, sizeof buf)) > 0) {
ssize_t wbytes;
char *bp = buf;
while (rbytes) {
wbytes = write(sv[0], buf , rbytes);
if (wbytes > 0) {
rbytes -= wbytes;
bp += wbytes;
} else
error(1, "write failed: %s", strerror(errno));
}
}
debug((DEBUG_FAT, "done processing cgi input"));
exit(0);
out:
if (query)
free(query);
if (file)
free(file);
if (url)
free(url);
return 0;
}
/*
* handle parsing a CGI header output, transposing a Status: header
* into the HTTP reply (ie, instead of "200 OK").
*/
static void
finish_cgi_output(http_req *request, int in, int nph)
{
char buf[WRSZ];
char *str;
ssize_t len;
ssize_t rbytes;
SIMPLEQ_HEAD(, headers) headers;
struct headers *hdr, *nhdr;
int write_header, nheaders = 0;
/* much of this code is like read_request()'s header loop. hmmm... */
SIMPLEQ_INIT(&headers);
write_header = nph == 0;
while (nph == 0 && (str = bozodgetln(in, &len, read)) != NULL) {
char *hdr_name, *hdr_value;
if (parse_header(str, len, &hdr_name, &hdr_value))
break;
/*
* The CGI 1.{1,2} spec both say that if the cgi program
* returns a `Status:' header field then the server MUST
* return it in the response. If the cgi program does
* not return any `Status:' header then the server should
* respond with 200 OK.
* XXX The CGI 1.1 and 1.2 specification differ slightly on
* this in that v1.2 says that the script MUST NOT return a
* `Status:' header if it is returning a `Location:' header.
* For compatibility we are going with the CGI 1.1 behavior.
*/
if (strcasecmp(hdr_name, "status") == 0) {
debug((DEBUG_OBESE, "process_cgi: writing HTTP header "
"from status %s ..", hdr_value));
bozoprintf("%s %s\r\n", request->hr_proto, hdr_value);
bozoflush(stdout);
write_header = 0;
free(hdr_name);
break;
}
hdr = bozomalloc(sizeof *hdr);
hdr->h_header = hdr_name;
hdr->h_value = hdr_value;
SIMPLEQ_INSERT_TAIL(&headers, hdr, h_next);
nheaders++;
}
if (write_header) {
debug((DEBUG_OBESE, "process_cgi: writing HTTP header .."));
bozoprintf("%s 200 OK\r\n", request->hr_proto);
bozoflush(stdout);
}
if (nheaders) {
debug((DEBUG_OBESE, "process_cgi: writing delayed HTTP "
"headers .."));
SIMPLEQ_FOREACH_SAFE(hdr, &headers, h_next, nhdr) {
bozoprintf("%s: %s\r\n", hdr->h_header, hdr->h_value);
free(hdr->h_header);
free(hdr);
}
bozoprintf("\r\n");
bozoflush(stdout);
}
/* XXX we should have some goo that times us out
*/
while ((rbytes = read(in, buf, sizeof buf)) > 0) {
ssize_t wbytes;
char *bp = buf;
while (rbytes) {
wbytes = bozowrite(STDOUT_FILENO, buf, rbytes);
if (wbytes > 0) {
rbytes -= wbytes;
bp += wbytes;
} else
error(1, "cgi output write failed: %s",
strerror(errno));
}
}
}
static int
parse_header(const char *str, ssize_t len, char **hdr_str, char **hdr_val)
{
char *name, *value;
/* if the string passed is zero-length bail out */
if (*str == '\0')
return -1;
value = bozostrdup(str);
/* locate the ':' separator in the header/value */
name = bozostrnsep(&value, ":", &len);
if (NULL == name || -1 == len) {
free(name);
return -1;
}
/* skip leading space/tab */
while (*value == ' ' || *value == '\t')
len--, value++;
*hdr_str = name;
*hdr_val = value;
return 0;
}
/*
* given the file name, return a CGI interpreter
*/
static const char *
content_cgihandler(http_req *request, const char *file)
{
struct content_map *map;
debug((DEBUG_FAT, "content_cgihandler: trying file %s", file));
map = match_content_map(file, 0);
if (map)
return (map->cgihandler);
return (NULL);
}
static void
append_index_html(char **url)
{
*url = bozorealloc(*url, strlen(*url) + strlen(index_html) + 1);
strcat(*url, index_html);
debug((DEBUG_NORMAL, "append_index_html: url adjusted to `%s'", *url));
}
#ifndef NO_DYNAMIC_CONTENT
/* cgi maps are simple ".postfix /path/to/prog" */
void
add_content_map_cgi(char *arg, char *cgihandler)
{
struct content_map *map;
debug((DEBUG_NORMAL, "add_content_map_cgi: name %s cgi %s", arg, cgihandler));
Cflag = 1;
map = get_content_map(arg);
map->name = arg;
map->type = map->encoding = map->encoding11 = NULL;
map->cgihandler = cgihandler;
}
#endif /* NO_DYNAMIC_CONTENT */
#endif /* NO_CGIBIN_SUPPORT */