/*
* Copyright (c) 2004-2005 Sergey Lyubka <valenok@gmail.com>
* All rights reserved
*
* "THE BEER-WARE LICENSE" (Revision 42):
* Sergey Lyubka wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return.
*/
#include "defs.h"
#if !defined(NO_CGI)
struct env_block {
char buf[ENV_MAX]; /* Environment buffer */
int len; /* Space taken */
char *vars[CGI_ENV_VARS]; /* Point into the buffer */
int nvars; /* Number of variables */
};
/*
* Verify that given file has CGI extension
*/
int
is_cgi(struct shttpd_ctx *ctx, const char *path)
{
size_t len, path_len;
const char *s = ctx->cgi_extensions;
path_len = strlen(path);
FOR_EACH_WORD_IN_LIST(s, len)
if (len < path_len &&
!my_strncasecmp(path + path_len - len, s, len))
return (1);
return (0);
}
/*
* UNIX socketpair() implementation. Why? Because Windows does not have it.
* Return 0 on success, -1 on error.
*/
static int
my_socketpair(struct conn *c, int sp[2])
{
struct sockaddr_in sa;
int sock, ret = -1;
socklen_t len = sizeof(sa);
(void) memset(&sa, 0, sizeof(sa));
sa.sin_family = AF_INET;
sa.sin_port = htons(0);
sa.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
if ((sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
} else if (bind(sock, (struct sockaddr *) &sa, len) != 0) {
elog(E_LOG, c, "mysocketpair: bind(): %d", ERRNO);
(void) closesocket(sock);
} else if (listen(sock, 1) != 0) {
elog(E_LOG, c, "mysocketpair: listen(): %d", ERRNO);
(void) closesocket(sock);
} else if (getsockname(sock, (struct sockaddr *) &sa, &len) != 0) {
elog(E_LOG, c, "mysocketpair: getsockname(): %d", ERRNO);
(void) closesocket(sock);
} else if ((sp[0] = socket(AF_INET, SOCK_STREAM, 6)) == -1) {
elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
(void) closesocket(sock);
} else if (connect(sp[0], (struct sockaddr *) &sa, len) != 0) {
elog(E_LOG, c, "mysocketpair: connect(): %d", ERRNO);
(void) closesocket(sock);
(void) closesocket(sp[0]);
} else if ((sp[1] = accept(sock,(struct sockaddr *) &sa, &len)) == -1) {
elog(E_LOG, c, "mysocketpair: accept(): %d", ERRNO);
(void) closesocket(sock);
(void) closesocket(sp[0]);
} else {
/* Success */
ret = 0;
(void) closesocket(sock);
}
#ifndef _WIN32
(void) fcntl(sp[0], F_SETFD, FD_CLOEXEC);
(void) fcntl(sp[1], F_SETFD, FD_CLOEXEC);
#endif /* _WIN32*/
return (ret);
}
static void
addenv(struct env_block *block, const char *fmt, ...)
{
int n, space;
va_list ap;
space = sizeof(block->buf) - block->len - 2;
assert(space >= 0);
va_start(ap, fmt);
n = vsnprintf(block->buf + block->len, space, fmt, ap);
va_end(ap);
if (n > 0 && n < space && block->nvars < CGI_ENV_VARS - 2) {
block->vars[block->nvars++] = block->buf + block->len;
block->len += n + 1; /* Include \0 terminator */
}
}
static void
add_http_headers_to_env(struct env_block *b, const char *s, int len)
{
const char *p, *v, *e = s + len;
int space, n, i, ch;
/* Loop through all headers in the request */
while (s < e) {
/* Find where this header ends. Remember where value starts */
for (p = s, v = NULL; p < e && *p != '\n'; p++)
if (v == NULL && *p == ':')
v = p;
/* 2 null terminators and "HTTP_" */
space = (sizeof(b->buf) - b->len) - (2 + 5);
assert(space >= 0);
/* Copy header if enough space in the environment block */
if (v > s && p > v + 2 && space > p - s) {
/* Store var */
if (b->nvars < (int) NELEMS(b->vars) - 1)
b->vars[b->nvars++] = b->buf + b->len;
(void) memcpy(b->buf + b->len, "HTTP_", 5);
b->len += 5;
/* Copy header name. Substitute '-' to '_' */
n = v - s;
for (i = 0; i < n; i++) {
ch = s[i] == '-' ? '_' : s[i];
b->buf[b->len++] = toupper(ch);
}
b->buf[b->len++] = '=';
/* Copy header value */
v += 2;
n = p[-1] == '\r' ? (p - v) - 1 : p - v;
for (i = 0; i < n; i++)
b->buf[b->len++] = v[i];
/* Null-terminate */
b->buf[b->len++] = '\0';
}
s = p + 1; /* Shift to the next header */
}
}
static void
prepare_environment(const struct conn *c, const char *prog,
struct env_block *blk)
{
const struct headers *h = &c->ch;
const char *s;
size_t len;
blk->len = blk->nvars = 0;
/* Prepare the environment block */
addenv(blk, "%s", "GATEWAY_INTERFACE=CGI/1.1");
addenv(blk, "%s", "SERVER_PROTOCOL=HTTP/1.1");
addenv(blk, "%s", "REDIRECT_STATUS=200"); /* PHP */
addenv(blk, "SERVER_PORT=%d", c->ctx->port);
addenv(blk, "SERVER_NAME=%s", c->ctx->auth_realm);
addenv(blk, "SERVER_ROOT=%s", c->ctx->document_root);
addenv(blk, "DOCUMENT_ROOT=%s", c->ctx->document_root);
addenv(blk, "REQUEST_METHOD=%s", known_http_methods[c->method].ptr);
addenv(blk, "REMOTE_ADDR=%s", inet_ntoa(c->sa.u.sin.sin_addr));
addenv(blk, "REMOTE_PORT=%hu", ntohs(c->sa.u.sin.sin_port));
addenv(blk, "REQUEST_URI=%s", c->uri);
addenv(blk, "SCRIPT_NAME=%s", prog + strlen(c->ctx->document_root));
addenv(blk, "SCRIPT_FILENAME=%s", prog); /* PHP */
addenv(blk, "PATH_TRANSLATED=%s", prog);
if (h->ct.v_vec.len > 0)
addenv(blk, "CONTENT_TYPE=%.*s",
h->ct.v_vec.len, h->ct.v_vec.ptr);
if (c->query != NULL)
addenv(blk, "QUERY_STRING=%s", c->query);
if (c->path_info != NULL)
addenv(blk, "PATH_INFO=/%s", c->path_info);
if (h->cl.v_big_int > 0)
addenv(blk, "CONTENT_LENGTH=%lu", h->cl.v_big_int);
if ((s = getenv("PATH")) != NULL)
addenv(blk, "PATH=%s", s);
#ifdef _WIN32
if ((s = getenv("COMSPEC")) != NULL)
addenv(blk, "COMSPEC=%s", s);
if ((s = getenv("SYSTEMROOT")) != NULL)
addenv(blk, "SYSTEMROOT=%s", s);
#else
if ((s = getenv("LD_LIBRARY_PATH")) != NULL)
addenv(blk, "LD_LIBRARY_PATH=%s", s);
#endif /* _WIN32 */
if ((s = getenv("PERLLIB")) != NULL)
addenv(blk, "PERLLIB=%s", s);
if (h->user.v_vec.len > 0) {
addenv(blk, "REMOTE_USER=%.*s",
h->user.v_vec.len, h->user.v_vec.ptr);
addenv(blk, "%s", "AUTH_TYPE=Digest");
}
/* Add user-specified variables */
s = c->ctx->cgi_vars;
FOR_EACH_WORD_IN_LIST(s, len)
addenv(blk, "%.*s", len, s);
/* Add all headers as HTTP_* variables */
add_http_headers_to_env(blk, c->headers,
c->rem.headers_len - (c->headers - c->request));
blk->vars[blk->nvars++] = NULL;
blk->buf[blk->len++] = '\0';
assert(blk->nvars < CGI_ENV_VARS);
assert(blk->len > 0);
assert(blk->len < (int) sizeof(blk->buf));
/* Debug stuff to view passed environment */
DBG(("%s: %d vars, %d env size", prog, blk->nvars, blk->len));
{
int i;
for (i = 0 ; i < blk->nvars; i++)
DBG(("[%s]", blk->vars[i] ? blk->vars[i] : "null"));
}
}
int
run_cgi(struct conn *c, const char *prog)
{
struct env_block blk;
char dir[FILENAME_MAX], *p;
int ret, pair[2];
prepare_environment(c, prog, &blk);
/* CGI must be executed in its own directory */
(void) my_snprintf(dir, sizeof(dir), "%s", prog);
for (p = dir + strlen(dir) - 1; p > dir; p--)
if (*p == '/') {
*p++ = '\0';
break;
}
if (my_socketpair(c, pair) != 0) {
ret = -1;
} else if (spawn_process(c, prog, blk.buf, blk.vars, pair[1], dir)) {
ret = -1;
(void) closesocket(pair[0]);
(void) closesocket(pair[1]);
} else {
ret = 0;
c->loc.chan.sock = pair[0];
}
return (ret);
}
void
do_cgi(struct conn *c)
{
DBG(("running CGI: [%s]", c->uri));
assert(c->loc.io.size > CGI_REPLY_LEN);
memcpy(c->loc.io.buf, CGI_REPLY, CGI_REPLY_LEN);
c->loc.io.head = c->loc.io.tail = c->loc.io.total = CGI_REPLY_LEN;
c->loc.io_class = &io_cgi;
c->loc.flags = FLAG_R;
if (c->method == METHOD_POST)
c->loc.flags |= FLAG_W;
}
#endif /* !NO_CGI */
