/*

* uhttpd - Tiny single-threaded httpd

*

* Copyright (C) 2010-2013 Jo-Philipp Wich <xm@subsignal.org>

* Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>

*

* Permission to use, copy, modify, and/or distribute this software for any

* purpose with or without fee is hereby granted, provided that the above

* copyright notice and this permission notice appear in all copies.

*

* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

*/

#include <arpa/inet.h>

#include <libubox/blobmsg.h>

#include "uhttpd.h"

#define __headers \

#undef __header

#define __header __enum_header

enum client_hdr {

__headers

__HDR_MAX,

};

#undef __header

#define __header __blobmsg_header

static const struct blobmsg_policy hdr_policy[__HDR_MAX] = {

__headers

};

static const struct {

const char *name;

int idx;

} proc_header_env[] = {

{ "HTTP_ACCEPT", HDR_accept },

{ "HTTP_ACCEPT_CHARSET", HDR_accept_charset },

{ "HTTP_ACCEPT_ENCODING", HDR_accept_encoding },

{ "HTTP_ACCEPT_LANGUAGE", HDR_accept_language },

{ "HTTP_AUTHORIZATION", HDR_authorization },

{ "HTTP_CONNECTION", HDR_connection },

{ "HTTP_COOKIE", HDR_cookie },

{ "HTTP_HOST", HDR_host },

{ "HTTP_REFERER", HDR_referer },

{ "HTTP_USER_AGENT", HDR_user_agent },

{ "HTTP_X_HTTP_METHOD_OVERRIDE", HDR_x_http_method_override },

{ "CONTENT_TYPE", HDR_content_type },

{ "CONTENT_LENGTH", HDR_content_length },

};

enum extra_vars {

};

static char local_addr[INET6_ADDRSTRLEN], remote_addr[INET6_ADDRSTRLEN];

static char local_port[6], remote_port[6];

static char redirect_status[4];

static struct env_var extra_vars[] = {

[_VAR_GW] = { "GATEWAY_INTERFACE", "CGI/1.1" },

[_VAR_SOFTWARE] = { "SERVER_SOFTWARE", "uhttpd" },

[VAR_SCRIPT_NAME] = { "SCRIPT_NAME" },

[VAR_SCRIPT_FILE] = { "SCRIPT_FILENAME" },

[VAR_DOCROOT] = { "DOCUMENT_ROOT" },

[VAR_QUERY] = { "QUERY_STRING" },

[VAR_REQUEST] = { "REQUEST_URI" },

[VAR_PROTO] = { "SERVER_PROTOCOL" },

[VAR_METHOD] = { "REQUEST_METHOD" },

[VAR_PATH_INFO] = { "PATH_INFO" },

[VAR_USER] = { "REMOTE_USER" },

[VAR_HTTPS] = { "HTTPS" },

[VAR_REDIRECT] = { "REDIRECT_STATUS", redirect_status },

[VAR_SERVER_NAME] = { "SERVER_NAME", local_addr },

[VAR_SERVER_ADDR] = { "SERVER_ADDR", local_addr },

[VAR_SERVER_PORT] = { "SERVER_PORT", local_port },

[VAR_REMOTE_NAME] = { "REMOTE_HOST", remote_addr },

[VAR_REMOTE_ADDR] = { "REMOTE_ADDR", remote_addr },

[VAR_REMOTE_PORT] = { "REMOTE_PORT", remote_port },

};

struct env_var *uh_get_process_vars(struct client *cl, struct path_info *pi)

{

struct http_request *req = &cl->request;

struct blob_attr *data = cl->hdr.head;

struct env_var *vars = (void *) uh_buf;

struct blob_attr *tb[__HDR_MAX];

const char *url;

int len;

int i;

url = blobmsg_data(blob_data(cl->hdr.head));

len = ARRAY_SIZE(proc_header_env);

len += ARRAY_SIZE(extra_vars);

len *= sizeof(struct env_var);

BUILD_BUG_ON(sizeof(uh_buf) < len);

extra_vars[VAR_SCRIPT_NAME].value = pi->name;

extra_vars[VAR_SCRIPT_FILE].value = pi->phys;

extra_vars[VAR_DOCROOT].value = pi->root;

extra_vars[VAR_QUERY].value = pi->query ? pi->query : "";

extra_vars[VAR_REQUEST].value = url;

extra_vars[VAR_PROTO].value = http_versions[req->version];

extra_vars[VAR_METHOD].value = http_methods[req->method];

extra_vars[VAR_PATH_INFO].value = pi->info;

extra_vars[VAR_USER].value = req->realm ? req->realm->user : NULL;

extra_vars[VAR_HTTPS].value = cl->tls ? "on" : NULL;

snprintf(redirect_status, sizeof(redirect_status),

"%d", req->redirect_status);

inet_ntop(cl->srv_addr.family, &cl->srv_addr.in, local_addr, sizeof(local_addr));

snprintf(local_port, sizeof(local_port), "%d", cl->srv_addr.port);

inet_ntop(cl->peer_addr.family, &cl->peer_addr.in, remote_addr, sizeof(remote_addr));

snprintf(remote_port, sizeof(remote_port), "%d", cl->peer_addr.port);

blobmsg_parse(hdr_policy, __HDR_MAX, tb, blob_data(data), blob_len(data));

for (i = 0; i < ARRAY_SIZE(proc_header_env); i++) {

struct blob_attr *cur;

cur = tb[proc_header_env[i].idx];

vars[i].name = proc_header_env[i].name;

vars[i].value = cur ? blobmsg_data(cur) : "";

}

memcpy(&vars[i], extra_vars, sizeof(extra_vars));

i += ARRAY_SIZE(extra_vars);

vars[i].name = NULL;

vars[i].value = NULL;

return vars;

}

static void proc_close_fds(struct client *cl)

{

struct dispatch_proc *p = &cl->dispatch.proc;

close(p->r.sfd.fd.fd);

if (p->wrfd.fd >= 0)

close(p->wrfd.fd);

}

static void proc_handle_close(struct relay *r, int ret)

{

if (r->header_cb) {

uh_client_error(r->cl, 502, "Bad Gateway",

"The process did not produce any response");

return;

}

uh_request_done(r->cl);

}

static void proc_handle_header(struct relay *r, const char *name, const char *val)

{

static char status_buf[64];

struct client *cl = r->cl;

char *sep;

char buf[4];

if (!strcmp(name, "Status")) {

sep = strchr(val, ' ');

if (sep != val + 3)

return;

memcpy(buf, val, 3);

buf[3] = 0;

snprintf(status_buf, sizeof(status_buf), "%s", sep + 1);

cl->dispatch.proc.status_msg = status_buf;

cl->dispatch.proc.status_code = atoi(buf);

return;

}

blobmsg_add_string(&cl->dispatch.proc.hdr, name, val);

}

static void proc_handle_header_end(struct relay *r)

{

struct client *cl = r->cl;

struct dispatch_proc *p = &cl->dispatch.proc;

struct blob_attr *cur;

int rem;

uloop_timeout_cancel(&p->timeout);

uh_http_header(cl, cl->dispatch.proc.status_code, cl->dispatch.proc.status_msg);

blob_for_each_attr(cur, cl->dispatch.proc.hdr.head, rem)

ustream_printf(cl->us, "%s: %s\r\n", blobmsg_name(cur), blobmsg_data(cur));

ustream_printf(cl->us, "\r\n");

if (cl->request.method == UH_HTTP_MSG_HEAD)

r->skip_data = true;

}

static void proc_write_close(struct client *cl)

{

struct dispatch_proc *p = &cl->dispatch.proc;

if (p->wrfd.fd < 0)

return;

uloop_fd_delete(&p->wrfd);

close(p->wrfd.fd);

p->wrfd.fd = -1;

}

static void proc_free(struct client *cl)

{

struct dispatch_proc *p = &cl->dispatch.proc;

uloop_timeout_cancel(&p->timeout);

blob_buf_free(&p->hdr);

proc_write_close(cl);

uh_relay_free(&p->r);

}

static void proc_write_cb(struct uloop_fd *fd, unsigned int events)

{

struct client *cl = container_of(fd, struct client, dispatch.proc.wrfd);

client_poll_post_data(cl);

}

static void proc_relay_write_cb(struct client *cl)

{

struct dispatch_proc *p = &cl->dispatch.proc;

if (ustream_pending_data(cl->us, true))

return;

ustream_set_read_blocked(&p->r.sfd.stream, false);

p->r.sfd.stream.notify_read(&p->r.sfd.stream, 0);

}

static int proc_data_send(struct client *cl, const char *data, int len)

{

struct dispatch_proc *p = &cl->dispatch.proc;

int retlen = 0;

int ret;

while (len) {

ret = write(p->wrfd.fd, data, len);

if (ret < 0) {

if (errno == EINTR)

continue;

if (errno == EAGAIN || errno == EWOULDBLOCK)

break;

/* consume all data */

ret = len;

}

if (!ret)

break;

retlen += ret;

len -= ret;

data += ret;

}

if (len)

uloop_fd_add(&p->wrfd, ULOOP_WRITE);

else

uloop_fd_delete(&p->wrfd);

return retlen;

}

static void proc_timeout_cb(struct uloop_timeout *timeout)

{

struct dispatch_proc *proc = container_of(timeout, struct dispatch_proc, timeout);

struct client *cl = container_of(proc, struct client, dispatch.proc);

uh_relay_kill(cl, &proc->r);

}

bool uh_create_process(struct client *cl, struct path_info *pi, char *url,

void (*cb)(struct client *cl, struct path_info *pi, char *url))

{

struct dispatch *d = &cl->dispatch;

struct dispatch_proc *proc = &d->proc;

int rfd[2], wfd[2];

int pid;

blob_buf_init(&proc->hdr, 0);

proc->status_code = 200;

proc->status_msg = "OK";

if (pipe(rfd))

return false;

if (pipe(wfd))

goto close_rfd;

pid = fork();

if (pid < 0)

goto close_wfd;

if (!pid) {

close(0);

close(1);

dup2(rfd[1], 1);

dup2(wfd[0], 0);

close(rfd[0]);

close(rfd[1]);

close(wfd[0]);

close(wfd[1]);

uh_close_fds();

cb(cl, pi, url);

exit(0);

}

close(rfd[1]);

close(wfd[0]);

proc->wrfd.fd = wfd[1];

uh_relay_open(cl, &proc->r, rfd[0], pid);

d->free = proc_free;

d->close_fds = proc_close_fds;

d->data_send = proc_data_send;

d->data_done = proc_write_close;

d->write_cb = proc_relay_write_cb;

proc->r.header_cb = proc_handle_header;

proc->r.header_end = proc_handle_header_end;

proc->r.close = proc_handle_close;

proc->wrfd.cb = proc_write_cb;

proc->timeout.cb = proc_timeout_cb;

if (conf.script_timeout > 0)

uloop_timeout_set(&proc->timeout, conf.script_timeout * 1000);

return true;

close_wfd:

close(wfd[0]);

close(wfd[1]);

close_rfd:

close(rfd[0]);

close(rfd[1]);

return false;

}