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// The contents of this file are subject to the BOINC Public License
// Version 1.0 (the "License"); you may not use this file except in
// compliance with the License. You may obtain a copy of the License at
// http://boinc.berkeley.edu/license_1.0.txt
//
// Software distributed under the License is distributed on an "AS IS"
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
// License for the specific language governing rights and limitations
// under the License.
//
// The Original Code is the Berkeley Open Infrastructure for Network Computing.
//
// The Initial Developer of the Original Code is the SETI@home project.
// Portions created by the SETI@home project are Copyright (C) 2002
// University of California at Berkeley. All Rights Reserved.
//
// Contributor(s):
//
#include "cpp.h"
#ifdef _WIN32
#include "boinc_win.h"
#define SHUT_WR SD_SEND
#endif
#ifndef _WIN32
#include <cstring>
#include <sstream>
#include <algorithm>
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if HAVE_ERRNO_H
#include <errno.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#endif
#include "error_numbers.h"
#include "filesys.h"
#include "util.h"
#include "client_msgs.h"
#include "http.h"
#include "base64.h"
#define HTTP_BLOCKSIZE 16384
using std::string;
using std::istringstream;
using std::vector;
// Breaks a HTTP url down into its server and file path components
//
void parse_url(const char* url, char* host, int &port, char* file) {
char* p;
char buf[256];
if (strncmp(url, "http://", 7) == 0) {
safe_strcpy(buf, url+7);
} else {
safe_strcpy(buf, url);
}
p = strchr(buf, '/');
if (p) {
strcpy(file, p+1);
*p = 0;
} else {
strcpy(file, "");
}
p=strchr(buf,':');
if (p) {
port = atol(p+1);
*p = 0;
} else {
port=80;
}
strcpy(host, buf);
}
// Prints an HTTP 1.1 GET request header into buf
// Hopefully there won't be chunked transfers in a GET
//
static void http_get_request_header(
char* buf, char* host, int port, char* file, double offset
) {
char offset_info[256];
if (offset) sprintf( offset_info, "Range: bytes=%.0f-\015\012", offset );
sprintf(buf,
"GET %s HTTP/1.0\015\012"
"User-Agent: BOINC client\015\012"
"Host: %s:%d\015\012"
"%s"
"Connection: close\015\012"
"Accept: */*\015\012"
"\015\012",
file, host, port, offset?offset_info:""
);
}
static void http_get_request_header_proxy(
char* buf, char* host, int port, char* file, double offset, char* encstr
) {
char offset_info[256];
if (offset) sprintf( offset_info, "Range: bytes=%.0f-\015\012", offset );
sprintf(buf,
"GET %s HTTP/1.0\015\012"
"User-Agent: BOINC client\015\012"
"Host: %s:%d\015\012"
"%s"
"Connection: close\015\012"
"Accept: */*\015\012"
"Proxy-Authorization: Basic %s\015\012"
"\015\012",
file, host, port, offset?offset_info:"", encstr
);
}
// Prints an HTTP 1.1 HEAD request header into buf
//
static void http_head_request_header(char* buf, char* host, int port, char* file) {
sprintf(buf,
"HEAD %s HTTP/1.0\015\012"
"User-Agent: BOINC client\015\012"
"Host: %s:%d\015\012"
"Connection: close\015\012"
"Accept: */*\015\012"
"\015\012",
file, host, port
);
}
static void http_head_request_header_proxy(char* buf, char* host, int port, char* file, char* encstr
) {
sprintf(buf,
"HEAD %s HTTP/1.0\015\012"
"User-Agent: BOINC client\015\012"
"Host: %s:%d\015\012"
"Connection: close\015\012"
"Accept: */*\015\012"
"Proxy-Authorization: Basic %s\015\012"
"\015\012",
file, host, port, encstr
);
}
// Prints an HTTP 1.0 POST request header into buf
// Use HTTP 1.0 so we don't have to deal with chunked transfers
//
static void http_post_request_header(
char* buf, char* host, int port, char* file, int size
) {
sprintf(buf,
"POST %s HTTP/1.0\015\012"
"Pragma: no-cache\015\012"
"Cache-Control: no-cache\015\012"
"Host: %s:%d\015\012"
"Connection: close\015\012"
"Content-Type: application/octet-stream\015\012"
"Content-Length: %d\015\012"
"\015\012",
file, host, port, size
);
}
static void http_post_request_header_proxy(
char* buf, char* host, int port, char* file, int size, char* encstr
) {
sprintf(buf,
"POST %s HTTP/1.0\015\012"
"Pragma: no-cache\015\012"
"Cache-Control: no-cache\015\012"
"Host: %s:%d\015\012"
"Connection: close\015\012"
"Content-Type: application/octet-stream\015\012"
"Content-Length: %d\015\012"
"Proxy-Authorization: Basic %s\015\012"
"\015\012",
file, host, port, size, encstr
);
}
void HTTP_REPLY_HEADER::init() {
http_status = 500;
content_length = 0;
redirect_location.erase();
recv_buf.erase();
}
void HTTP_REPLY_HEADER::parse() {
SCOPE_MSG_LOG scope_messages(log_messages, CLIENT_MSG_LOG::DEBUG_HTTP);
istringstream h(recv_buf);
string line, w;
if (getline(h, line)) {
istringstream iline(line);
iline >> w;
if (!starts_with(w,"HTTP/")) {
scope_messages.printf("HTTP_REPLY_HEADER::parse(): not HTTP\n");
return;
}
iline >> http_status;
scope_messages.printf("HTTP_REPLY_HEADER::parse(): status=%d\n", http_status);
}
while (getline(h, line)) {
istringstream iline(line);
iline >> w;
downcase_string(w);
if (w == "content-length:") {
iline >> content_length;
scope_messages.printf("HTTP_REPLY_HEADER::parse(): content_length=%d\n", content_length);
} else if (w == "location:") {
iline >> redirect_location;
scope_messages.printf("HTTP_REPLY_HEADER::parse(): redirect_location=%s\n", redirect_location.c_str());
}
}
}
const unsigned int MAX_HEADER_SIZE = 1024;
// Parse an http reply header into the header struct
//
// Returns 1 if not done yet, 0 if done (header.http_status indicates success)
//
int HTTP_REPLY_HEADER::read_reply(int socket) {
SCOPE_MSG_LOG scope_messages(log_messages, CLIENT_MSG_LOG::DEBUG_HTTP);
while (recv_buf.size() < MAX_HEADER_SIZE) {
char c;
errno = 0;
int n = recv(socket, &c, 1, 0);
if (n != 1) {
scope_messages.printf(
"HTTP_REPLY_HEADER::read_reply(): recv() on socket %d returned %d errno %d sockerr %d\n",
socket, n, errno, get_socket_error(socket)
);
}
if (n == -1 && errno == EAGAIN) {
return 1;
}
// if n is zero, we've reached EOF (and that's an error)
//
if (n != 1) {
break;
}
if (c == '\r') continue;
recv_buf += c;
if (ends_with(recv_buf, "\n\n")) {
scope_messages.printf_multiline(recv_buf.c_str(),
"HTTP_REPLY_HEADER::read_reply(): header: "
);
parse();
return 0;
}
}
// error occurred; status will be 500 (from constructor)
//
scope_messages.printf(
"HTTP_REPLY_HEADER::read_reply(): returning error (recv_buf=%s)\n",
recv_buf.c_str()
);
return 0;
}
// Read the contents of the socket into buf
//
static int read_reply(int socket, char* buf, int len) {
int i, n;
for (i=0; i<len-1; i++) {
n = recv(socket, buf+i, 1, 0);
if (n != 1) break;
}
buf[i] = 0;
return 0;
}
HTTP_OP::HTTP_OP() {
strcpy(url_hostname, "");
strcpy(filename, "");
req1 = NULL;
strcpy(infile, "");
strcpy(outfile, "");
content_length = 0;
file_offset = 0;
strcpy(request_header, "");
http_op_state = HTTP_STATE_IDLE;
http_op_type = HTTP_OP_NONE;
http_op_retval = 0;
//// proxy_auth_done = false;
}
HTTP_OP::~HTTP_OP() {
}
// Initialize HTTP HEAD operation
//
int HTTP_OP::init_head(const char* url) {
char proxy_buf[256];
parse_url(url, url_hostname, port, filename);
//// if(!proxy_auth_done){
//// parse_url(url, url_hostname, port, filename);
//// }
PROXY::init(url_hostname, port);
NET_XFER::init(get_proxy_server_name(url_hostname),get_proxy_port(port), HTTP_BLOCKSIZE);
http_op_type = HTTP_OP_HEAD;
http_op_state = HTTP_STATE_CONNECTING;
if (pi.use_http_proxy) {
sprintf(proxy_buf, "http://%s:%d/%s", url_hostname, port, filename);
} else {
sprintf(proxy_buf, "/%s", filename);
}
// http_head_request_header(request_header, url_hostname, port, proxy_buf);
//// if(!proxy_auth_done){
if(!pi.use_http_auth){
http_head_request_header(
request_header, url_hostname, port, proxy_buf
);
}else{
char id_passwd[512];
string encstr = "";
memset(id_passwd,0,sizeof(id_passwd));
strcpy(id_passwd,pi.http_user_name);
strcat(id_passwd,":");
strcat(id_passwd,pi.http_user_passwd);
encstr = r_base64_encode(id_passwd,strlen(id_passwd));
http_head_request_header_proxy(
request_header, url_hostname, port, proxy_buf, (char*)encstr.c_str()
);
}
return 0;
}
// Initialize HTTP GET operation
//
int HTTP_OP::init_get(const char* url, char* out, bool del_old_file, double off) {
char proxy_buf[256];
if (del_old_file) {
unlink(out);
}
file_offset = off;
parse_url(url, url_hostname, port, filename);
//// if(!proxy_auth_done){
//// parse_url(url, url_hostname, port, filename);
//// }
PROXY::init(url_hostname, port);
NET_XFER::init(get_proxy_server_name(url_hostname),get_proxy_port(port), HTTP_BLOCKSIZE);
safe_strcpy(outfile, out);
if (off != 0){
bytes_xferred = off;
}
http_op_type = HTTP_OP_GET;
http_op_state = HTTP_STATE_CONNECTING;
if (pi.use_http_proxy) {
sprintf(proxy_buf, "http://%s:%d/%s", url_hostname, port, filename);
} else {
sprintf(proxy_buf, "/%s", filename);
}
// http_get_request_header(request_header, url_hostname, port, proxy_buf, (int)file_offset);
//// if(!proxy_auth_done){
if(!pi.use_http_auth){
http_get_request_header(request_header, url_hostname, port, proxy_buf, (int)file_offset);
}else{
char id_passwd[512];
string encstr = "";
memset(id_passwd,0,sizeof(id_passwd));
strcpy(id_passwd,pi.http_user_name);
strcat(id_passwd,":");
strcat(id_passwd,pi.http_user_passwd);
encstr = r_base64_encode(id_passwd,strlen(id_passwd));
http_get_request_header_proxy(request_header, url_hostname,
port, proxy_buf, (int)file_offset, (char*)encstr.c_str() );
}
return 0;
}
// Initialize HTTP POST operation
//
int HTTP_OP::init_post(const char* url, char* in, char* out) {
int retval;
double size;
char proxy_buf[256];
SCOPE_MSG_LOG scope_messages(log_messages, CLIENT_MSG_LOG::DEBUG_HTTP);
parse_url(url, url_hostname, port, filename);
PROXY::init(url_hostname, port);
NET_XFER::init(get_proxy_server_name(url_hostname),get_proxy_port(port), HTTP_BLOCKSIZE);
safe_strcpy(infile, in);
safe_strcpy(outfile, out);
retval = file_size(infile, size);
if (retval) return retval;
content_length = (int)size;
http_op_type = HTTP_OP_POST;
http_op_state = HTTP_STATE_CONNECTING;
if (pi.use_http_proxy) {
sprintf(proxy_buf, "http://%s:%d/%s", url_hostname, port, filename);
} else {
sprintf(proxy_buf, "/%s", filename);
}
if (!pi.use_http_auth){
http_post_request_header(
request_header, url_hostname, port, proxy_buf, content_length
);
} else {
char id_passwd[512];
string encstr = "";
memset(id_passwd,0,sizeof(id_passwd));
strcpy(id_passwd,pi.http_user_name);
strcat(id_passwd,":");
strcat(id_passwd,pi.http_user_passwd);
encstr = r_base64_encode(id_passwd,strlen(id_passwd));
http_post_request_header_proxy(
request_header, url_hostname, port, proxy_buf, content_length,
(char*)encstr.c_str()
);
}
scope_messages.printf("HTTP_OP::init_post(): %p io_done %d\n", this, io_done);
return 0;
}
// Initialize HTTP POST operation
//
int HTTP_OP::init_post2(
const char* url, char* r1, char* in, double offset
) {
int retval;
double size;
char proxy_buf[256];
parse_url(url, url_hostname, port, filename);
PROXY::init(url_hostname, port);
NET_XFER::init(get_proxy_server_name(url_hostname),get_proxy_port(port), HTTP_BLOCKSIZE);
req1 = r1;
if (in) {
safe_strcpy(infile, in);
file_offset = offset;
retval = file_size(infile, size);
if (retval) {
printf("HTTP::init_post2: couldn't get file size\n");
return retval;
}
content_length = (int)size - (int)offset;
}
content_length += strlen(req1);
http_op_type = HTTP_OP_POST2;
http_op_state = HTTP_STATE_CONNECTING;
if (pi.use_http_proxy) {
sprintf(proxy_buf, "http://%s:%d/%s", url_hostname, port, filename);
} else {
sprintf(proxy_buf, "/%s", filename);
}
if (!pi.use_http_auth){
http_post_request_header(
request_header, url_hostname, port, proxy_buf, content_length
);
} else {
char id_passwd[512];
string encstr = "";
memset(id_passwd,0,sizeof(id_passwd));
strcpy(id_passwd,pi.http_user_name);
strcat(id_passwd,":");
strcat(id_passwd,pi.http_user_passwd);
encstr = r_base64_encode(id_passwd,strlen(id_passwd));
http_post_request_header_proxy(
request_header, url_hostname, port, proxy_buf, content_length,
(char*)encstr.c_str()
);
}
return 0;
}
// Returns true if the HTTP operation is complete
//
bool HTTP_OP::http_op_done() {
return (http_op_state == HTTP_STATE_DONE);
}
HTTP_OP_SET::HTTP_OP_SET(NET_XFER_SET* p) {
net_xfers = p;
}
// Adds an HTTP_OP to the set
//
int HTTP_OP_SET::insert(HTTP_OP* ho) {
int retval;
retval = net_xfers->insert(ho);
if (retval) return retval;
http_ops.push_back(ho);
return 0;
}
bool HTTP_OP_SET::poll() {
unsigned int i;
HTTP_OP* htp;
int n, retval;
bool action = false;
SCOPE_MSG_LOG scope_messages(log_messages, CLIENT_MSG_LOG::DEBUG_HTTP);
for (i=0; i<http_ops.size(); i++) {
htp = http_ops[i];
if (htp->error) {
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = htp->error;
action = true;
continue;
}
switch(htp->http_op_state) {
case HTTP_STATE_CONNECTING:
if (htp->is_connected) {
htp->http_op_state = HTTP_STATE_SOCKS_CONNECT;
htp->want_upload = true;
action = true;
}
break;
case HTTP_STATE_SOCKS_CONNECT:
// Since the HTTP layer is synchronous with the proxy layer, we
// call proxy_poll() here instead of in do_something()
htp->proxy_poll();
// After negotiation with the proxy is complete, advance to
// the next step of the HTTP layer
if (htp->proxy_negotiated()) {
if (htp->proxy_retval) {
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = htp->proxy_retval;
switch (htp->proxy_retval) {
case ERR_SOCKS_UNKNOWN_FAILURE:
msg_printf(NULL, MSG_ERROR, "An unknown SOCKS server error occurred\n");
break;
case ERR_SOCKS_REQUEST_FAILED:
msg_printf(NULL, MSG_ERROR, "The SOCKS server denied access for this computer\n");
break;
case ERR_SOCKS_BAD_USER_PASS:
msg_printf(NULL, MSG_ERROR, "Incorrect SOCKS user name and/or password\n");
break;
case ERR_SOCKS_UNKNOWN_SERVER_VERSION:
msg_printf(NULL, MSG_ERROR, "The SOCKS server is using an unknown version\n");
break;
case ERR_SOCKS_UNSUPPORTED:
msg_printf(NULL, MSG_ERROR, "The SOCKS server is using unsupported features unknown to BOINC\n");
break;
case ERR_SOCKS_CANT_REACH_HOST:
msg_printf(NULL, MSG_ERROR, "The SOCKS server is unable to contact the host\n");
break;
case ERR_SOCKS_CONN_REFUSED:
msg_printf(NULL, MSG_ERROR, "The connection from the SOCKS server to the host was refused\n");
break;
}
} else {
htp->http_op_state = HTTP_STATE_REQUEST_HEADER;
}
}
break;
case HTTP_STATE_REQUEST_HEADER:
if (htp->io_ready) {
action = true;
n = send(
htp->socket, htp->request_header,
strlen(htp->request_header), 0
);
scope_messages.printf(
"HTTP_OP_SET::poll(): wrote HTTP header to socket %d: %d bytes\n",
htp->socket, n
);
scope_messages.printf_multiline(htp->request_header, "HTTP_OP_SET::poll(): request header: ");
htp->io_ready = false;
switch(htp->http_op_type) {
case HTTP_OP_POST:
htp->http_op_state = HTTP_STATE_REQUEST_BODY;
htp->file = fopen(htp->infile, "rb");
if (!htp->file) {
msg_printf(NULL, MSG_ERROR, "HTTP_OP_SET::poll(): no input file %s\n", htp->infile);
htp->io_done = true;
htp->http_op_retval = ERR_FOPEN;
htp->http_op_state = HTTP_STATE_DONE;
break;
}
htp->do_file_io = true;
break;
case HTTP_OP_GET:
case HTTP_OP_HEAD:
htp->hrh.init();
htp->http_op_state = HTTP_STATE_REPLY_HEADER;
htp->want_upload = false;
htp->want_download = true;
// We don't need to write to the socket anymore.
// Close the read fd on the receiving side.
// This is needed by the scheduler "use_file" mechanism
// NOTE: this is commented out because
// - it seems to cause problems on all platforms
// in Windows it exercises a problem with Norton Firewall
#ifndef _WIN32
//shutdown(htp->socket, SHUT_WR);
#endif
break;
case HTTP_OP_POST2:
htp->http_op_state = HTTP_STATE_REQUEST_BODY1;
break;
}
}
break;
case HTTP_STATE_REQUEST_BODY1:
if (htp->io_ready) {
action = true;
n = send(htp->socket, htp->req1, strlen(htp->req1), 0);
htp->http_op_state = HTTP_STATE_REQUEST_BODY;
if (htp->infile && strlen(htp->infile) > 0) {
htp->file = fopen(htp->infile, "rb");
if (!htp->file) {
msg_printf(NULL, MSG_ERROR, "HTTP_OP_SET::poll(): no input2 file %s\n", htp->infile);
htp->io_done = true;
htp->http_op_retval = ERR_FOPEN;
htp->http_op_state = HTTP_STATE_DONE;
break;
}
fseek(htp->file, (long)htp->file_offset, SEEK_SET);
htp->do_file_io = true;
} else {
htp->io_done = true;
htp->do_file_io = false;
}
htp->io_ready = false;
}
break;
case HTTP_STATE_REQUEST_BODY:
if (htp->io_done) {
action = true;
scope_messages.printf("HTTP_OP_SET::poll(): finished sending request body\n");
htp->hrh.init();
htp->http_op_state = HTTP_STATE_REPLY_HEADER;
if (htp->file) {
fclose(htp->file);
htp->file = 0;
}
htp->do_file_io = false;
htp->want_upload = false;
htp->want_download = true;
htp->io_ready = false;
htp->io_done = false;
// We don't need to write to the socket anymore.
// Close the read fd on the receiving side.
// This is needed by the scheduler "use_file" mechanism
// NOTE: this is commented out because
// - it seems to cause problems on all platforms
// in Windows it exercises a problem with Norton Firewall
#ifndef _WIN32
//shutdown(htp->socket, SHUT_WR);
#endif
}
break;
case HTTP_STATE_REPLY_HEADER:
if (htp->io_ready) {
action = true;
scope_messages.printf(
"HTTP_OP_SET::poll(): reading reply header; io_ready %d io_done %d\n",
htp->io_ready, htp->io_done
);
if (htp->hrh.read_reply(htp->socket)) {
// not done yet
htp->io_ready = false;
break;
}
// TODO: handle all kinds of redirects here
if (htp->hrh.http_status == HTTP_STATUS_MOVED_PERM || htp->hrh.http_status == HTTP_STATUS_MOVED_TEMP) {
htp->close_socket();
retval = 0;
const char* new_url = htp->hrh.redirect_location.c_str();
if (!new_url || !strlen(new_url)) {
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = retval;
break;
}
switch (htp->http_op_type) {
case HTTP_OP_HEAD:
htp->init_head(new_url);
break;
case HTTP_OP_GET:
htp->init_get(new_url, htp->outfile, false);
break;
case HTTP_OP_POST:
htp->init_post(new_url, htp->infile, htp->outfile);
break;
case HTTP_OP_POST2:
htp->init_post2(new_url, htp->req1, htp->infile, htp->file_offset);
break;
}
// Open connection to the redirected server
//
retval = htp->open_server();
if (retval) {
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = retval;
}
break;
}
if (htp->hrh.http_status == HTTP_STATUS_PROXY_AUTH_REQ) {
htp->close_socket();
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = htp->hrh.http_status;
msg_printf(NULL, MSG_ERROR, "HTTP_OP_SET::poll(): Proxy Authentication Failed\n");
break;
}
if ((htp->hrh.http_status/100)*100 != HTTP_STATUS_OK) {
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = htp->hrh.http_status;
break;
}
switch (htp->http_op_type) {
case HTTP_OP_HEAD:
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = 0;
break;
case HTTP_OP_POST:
retval = unlink(htp->outfile);
// no error check here because file need not already exist
//
// fall through
case HTTP_OP_GET:
htp->http_op_state = HTTP_STATE_REPLY_BODY;
htp->file = boinc_fopen(htp->outfile, "ab");
if (!htp->file) {
msg_printf(NULL, MSG_ERROR,
"HTTP_OP_SET::poll(): can't open output file %s\n",
htp->outfile
);
htp->io_done = true;
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = ERR_FOPEN;
break;
}
htp->do_file_io = true;
break;
case HTTP_OP_POST2:
htp->http_op_state = HTTP_STATE_REPLY_BODY;
htp->io_ready = false;
htp->io_done = true;
break;
}
}
break;
case HTTP_STATE_REPLY_BODY:
if (htp->io_done) {
action = true;
switch(htp->http_op_type) {
case HTTP_OP_POST2:
read_reply(htp->socket, htp->req1, 256);
// parse reply here?
break;
default:
fclose(htp->file);
htp->file = 0;
break;
}
scope_messages.printf("HTTP_OP_SET::poll(): got reply body\n");
htp->http_op_state = HTTP_STATE_DONE;
htp->http_op_retval = 0;
}
break;
}
}
return action;
}
// Remove an HTTP_OP from the set
//
int HTTP_OP_SET::remove(HTTP_OP* p) {
vector<HTTP_OP*>::iterator iter;
net_xfers->remove(p);
iter = http_ops.begin();
while (iter != http_ops.end()) {
if (*iter == p) {
http_ops.erase(iter);
return 0;
}
iter++;
}
msg_printf(NULL, MSG_ERROR, "HTTP_OP_SET::remove(): not found\n");
return ERR_NOT_FOUND;
}
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