boinc/sched/file_upload_handler.cpp

744 lines
22 KiB
C++

// This file is part of BOINC.
// http://boinc.berkeley.edu
// Copyright (C) 2008 University of California
//
// BOINC is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License
// as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// BOINC 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with BOINC. If not, see <http://www.gnu.org/licenses/>.
// The BOINC file upload handler.
// See doc/upload.php for protocol spec.
//
#include "config.h"
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <sys/stat.h>
#include <sys/types.h>
#include <cerrno>
#include <unistd.h>
#include <csignal>
#include <fcntl.h>
#include <string>
#ifdef _USING_FCGI_
#include "boinc_fcgi.h"
#else
#include <cstdio>
#endif
#include "crypt.h"
#include "error_numbers.h"
#include "filesys.h"
#include "parse.h"
#include "str_replace.h"
#include "str_util.h"
#include "svn_version.h"
#include "util.h"
#include "sched_config.h"
#include "sched_msgs.h"
#include "sched_util.h"
using std::string;
#define LOCK_FILES
// comment this out to not lock files
// this may avoid filesystem hangs
#define ERR_TRANSIENT true
#define ERR_PERMANENT false
char this_filename[256];
double start_time();
inline static const char* get_remote_addr() {
char* p = getenv("REMOTE_ADDR");
if (p) return p;
return "Unknown remote address";
}
int return_error(bool transient, const char* message, ...) {
va_list va;
va_start(va, message);
char buf[10240];
vsprintf(buf, message, va);
va_end(va);
fprintf(stdout,
"Content-type: text/plain\n\n"
"<data_server_reply>\n"
" <status>%d</status>\n"
" <message>%s</message>\n"
"</data_server_reply>\n",
transient?1:-1,
buf
);
log_messages.printf(MSG_NORMAL,
"Returning error to client %s: %s (%s)\n",
get_remote_addr(), buf,
transient?"transient":"permanent"
);
return 1;
}
int return_success(const char* text) {
fprintf(stdout,
"Content-type: text/plain\n\n"
"<data_server_reply>\n"
" <status>0</status>\n"
);
if (text) {
fprintf(stdout, " %s\n", text);
}
fprintf(stdout, "</data_server_reply>\n");
return 0;
}
#define BLOCK_SIZE (256*1024)
double bytes_left=-1;
int accept_empty_file(char* path) {
int fd = open(path,
O_WRONLY|O_CREAT,
S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH
);
if (fd<0) {
return return_error(ERR_TRANSIENT,
"can't open file %s: %s\n", path, strerror(errno)
);
}
close(fd);
return return_success(0);
}
// read from socket, write to file
// ALWAYS returns an HTML reply
//
int copy_socket_to_file(FILE* in, char* path, double offset, double nbytes) {
unsigned char buf[BLOCK_SIZE];
struct stat sbuf;
int pid, fd=0;
// caller guarantees that nbytes > offset
//
bytes_left = nbytes - offset;
while (bytes_left > 0) {
int n, m, to_write;
m = bytes_left<(double)BLOCK_SIZE ? (int)bytes_left : BLOCK_SIZE;
// try to get m bytes from socket (n>=0 is number actually returned)
//
n = fread(buf, 1, m, in);
// delay opening the file until we've done the first socket read
// to avoid filesystem lockups (WCG, possible paranoia)
//
if (!fd) {
// Use raw IO not buffered IO so that we can use reliable
// posix file locking.
// Advisory file locking is not guaranteed reliable when
// used with stream buffered IO.
//
fd = open(path,
O_WRONLY|O_CREAT,
S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH
);
if (fd<0) {
return return_error(ERR_TRANSIENT,
"can't open file %s: %s\n", path, strerror(errno)
);
}
#ifdef LOCK_FILES
// Put an advisory lock on the file.
// This will prevent OTHER instances of file_upload_handler
// from being able to write to the file.
//
pid = mylockf(fd);
if (pid>0) {
close(fd);
return return_error(ERR_TRANSIENT,
"can't lock file %s: %s locked by PID=%d\n",
path, strerror(errno), pid
);
} else if (pid < 0) {
close(fd);
return return_error(ERR_TRANSIENT, "can't lock file %s\n", path);
}
#endif
// check that file length corresponds to offset
// TODO: use a 64-bit variant
//
if (stat(path, &sbuf)) {
close(fd);
return return_error(ERR_TRANSIENT,
"can't stat file %s: %s\n", path, strerror(errno)
);
}
if (sbuf.st_size < offset) {
close(fd);
return return_error(ERR_TRANSIENT,
"length of file %s %d bytes < offset %.0f bytes",
path, (int)sbuf.st_size, offset
);
}
if (offset) lseek(fd, offset, SEEK_SET);
if (sbuf.st_size > offset) {
log_messages.printf(MSG_CRITICAL,
"file %s length on disk %d bytes; host upload starting at %.0f bytes.\n",
this_filename, (int)sbuf.st_size, offset
);
}
}
// try to write n bytes to file
//
to_write=n;
while (to_write > 0) {
ssize_t ret = write(fd, buf+n-to_write, to_write);
if (ret < 0) {
close(fd);
const char* errmsg;
if (errno == ENOSPC) {
errmsg = "No space left on server";
} else {
errmsg = strerror(errno);
}
return return_error(ERR_TRANSIENT,
"can't write file %s: %s\n", path, errmsg
);
}
to_write -= ret;
}
// check that we got all bytes from socket that were requested
// Note: fread() reads less than requested only if there's
// an error or EOF (see the man page)
//
if (n != m) {
close(fd);
if (feof(in)) {
return return_error(ERR_TRANSIENT,
"EOF on socket read : asked for %d, got %d\n",
m, n
);
} else if (ferror(in)) {
return return_error(ERR_TRANSIENT,
"error %d (%s) on socket read: asked for %d, got %d\n",
ferror(in), strerror(ferror(in)), m, n
);
} else {
return return_error(ERR_TRANSIENT,
"incomplete socket read: asked for %d, got %d\n",
m, n
);
}
}
bytes_left -= n;
}
close(fd);
return return_success(0);
}
// read from socket, discard data
//
void copy_socket_to_null(FILE* in) {
unsigned char buf[BLOCK_SIZE];
while (1) {
int n = fread(buf, 1, BLOCK_SIZE, in);
if (n <= 0) return;
}
}
// ALWAYS generates an HTML reply
//
int handle_file_upload(FILE* in, R_RSA_PUBLIC_KEY& key) {
char buf[256], path[MAXPATHLEN], signed_xml[1024];
char name[256], stemp[256];
double max_nbytes=-1;
char xml_signature[1024];
int retval;
double offset=0, nbytes = -1;
bool is_valid, btemp;
strcpy(name, "");
strcpy(xml_signature, "");
bool found_data = false;
while (fgets(buf, 256, in)) {
#if 1
log_messages.printf(MSG_NORMAL, "got:%s\n", buf);
#endif
if (match_tag(buf, "<file_info>")) continue;
if (match_tag(buf, "</file_info>")) continue;
if (match_tag(buf, "<signed_xml>")) continue;
if (match_tag(buf, "</signed_xml>")) continue;
if (parse_bool(buf, "generated_locally", btemp)) continue;
if (parse_bool(buf, "upload_when_present", btemp)) continue;
if (parse_str(buf, "<url>", stemp, sizeof(stemp))) continue;
if (parse_str(buf, "<md5_cksum>", stemp, sizeof(stemp))) continue;
if (match_tag(buf, "<xml_signature>")) {
copy_element_contents(
in, "</xml_signature>", xml_signature, sizeof(xml_signature)
);
continue;
}
if (parse_str(buf, "<name>", name, sizeof(name))) {
safe_strcpy(this_filename, name);
continue;
}
if (parse_double(buf, "<max_nbytes>", max_nbytes)) continue;
if (parse_double(buf, "<offset>", offset)) continue;
if (parse_double(buf, "<nbytes>", nbytes)) continue;
if (match_tag(buf, "<data>")) {
found_data = true;
break;
}
log_messages.printf(MSG_CRITICAL, "unrecognized: %s", buf);
}
if (strlen(name) == 0) {
return return_error(ERR_PERMANENT, "Missing name");
}
if (!found_data) {
return return_error(ERR_PERMANENT, "Missing <data> tag");
}
if (!config.ignore_upload_certificates) {
if (strlen(xml_signature) == 0) {
return return_error(ERR_PERMANENT, "missing signature");
}
if (max_nbytes < 0) {
return return_error(ERR_PERMANENT, "missing max_nbytes");
}
sprintf(signed_xml,
"<name>%s</name><max_nbytes>%.0f</max_nbytes>",
name, max_nbytes
);
retval = check_string_signature(
signed_xml, xml_signature, key, is_valid
);
if (retval || !is_valid) {
log_messages.printf(MSG_CRITICAL,
"check_string_signature() [%s] [%s] retval %d, is_valid = %d\n",
signed_xml, xml_signature,
retval, is_valid
);
log_messages.printf(MSG_NORMAL, "signed xml: %s\n", signed_xml);
log_messages.printf(MSG_NORMAL, "signature: %s\n", xml_signature);
return return_error(ERR_PERMANENT, "invalid signature");
}
}
if (nbytes < 0) {
return return_error(ERR_PERMANENT, "nbytes missing or negative");
}
// enforce limits in signed XML
//
if (!config.ignore_upload_certificates) {
if (nbytes > max_nbytes) {
sprintf(buf,
"file size (%d KB) exceeds limit (%d KB)",
(int)(nbytes/1024), (int)(max_nbytes/1024)
);
copy_socket_to_null(in);
return return_error(ERR_PERMANENT, buf);
}
}
// make sure filename is legit
//
if (strstr(name, "..")) {
return return_error(ERR_PERMANENT,
"file_upload_handler: .. found in filename: %s",
name
);
}
if (strlen(name) == 0) {
return return_error(ERR_PERMANENT,
"file_upload_handler: no filename; nbytes %f", nbytes
);
}
retval = dir_hier_path(
name, config.upload_dir, config.uldl_dir_fanout,
path, true
);
if (retval) {
log_messages.printf(MSG_CRITICAL,
"Failed to find/create directory for file '%s' in '%s'\n",
name, config.upload_dir
);
return return_error(ERR_TRANSIENT, "can't open file");
}
log_messages.printf(MSG_NORMAL,
"Starting upload of %s from %s [offset=%.0f, nbytes=%.0f]\n",
name,
get_remote_addr(),
offset, nbytes
);
#ifndef _USING_FCGI_
fflush(stderr);
#endif
if (nbytes == 0) {
retval = accept_empty_file(path);
log_messages.printf(MSG_NORMAL,
"accepted empty file %s from %s\n", name, get_remote_addr()
);
} else {
if (offset >= nbytes) {
log_messages.printf(MSG_CRITICAL,
"ERROR: offset >= nbytes!!\n"
);
return return_success(0);
}
retval = copy_socket_to_file(in, path, offset, nbytes);
log_messages.printf(MSG_NORMAL,
"Ended upload of %s from %s; retval %d\n",
name,
get_remote_addr(),
retval
);
}
#ifndef _USING_FCGI_
fflush(stderr);
#endif
return retval;
}
bool volume_full(char* path) {
double total, avail;
int retval = get_filesystem_info(total, avail, path);
if (retval) return false;
if (avail<1e6) {
return true;
}
return false;
}
// always returns HTML reply
//
int handle_get_file_size(char* file_name) {
struct stat sbuf;
char path[MAXPATHLEN], buf[256];
int retval, pid, fd;
// TODO: check to ensure path doesn't point somewhere bad
// Use 64-bit variant
//
retval = dir_hier_path(
file_name, config.upload_dir, config.uldl_dir_fanout, path
);
if (retval) {
log_messages.printf(MSG_CRITICAL,
"Failed to find/create directory for file '%s' in '%s'.\n",
file_name, config.upload_dir
);
return return_error(ERR_TRANSIENT, "can't open file");
}
// if the volume is full, report a transient error
// to prevent the client from starting a transfer
//
if (volume_full(config.upload_dir)) {
return return_error(ERR_TRANSIENT, "Server is out of disk space");
}
fd = open(path, O_WRONLY|O_APPEND);
if (fd<0 && ENOENT==errno) {
// file does not exist: return zero length
//
log_messages.printf(MSG_NORMAL,
"handle_get_file_size(): [%s] returning zero\n", file_name
);
return return_success("<file_size>0</file_size>");
}
if (fd<0) {
// can't get file descriptor: try again later
//
log_messages.printf(MSG_CRITICAL,
"handle_get_file_size(): cannot open [%s] %s\n",
file_name, strerror(errno)
);
return return_error(ERR_TRANSIENT, "can't open file");
}
if ((pid = mylockf(fd))) {
// file locked by another file_upload_handler: try again later
//
close(fd);
log_messages.printf(MSG_CRITICAL,
"handle_get_file_size(): [%s] returning error\n", file_name
);
return return_error(ERR_TRANSIENT,
"[%s] locked by file_upload_handler PID=%d", file_name, pid
);
}
// file exists, writable, not locked by anyone else, so return length.
//
retval = stat(path, &sbuf);
close(fd);
if (retval) {
// file DOES perhaps exist, but can't stat it: try again later
//
log_messages.printf(MSG_CRITICAL,
"handle_get_file_size(): [%s] returning error %s\n",
file_name, strerror(errno)
);
return return_error(ERR_TRANSIENT, "cannot stat file" );
}
log_messages.printf(MSG_NORMAL,
"handle_get_file_size(): [%s] returning %d\n",
file_name, (int)sbuf.st_size
);
sprintf(buf, "<file_size>%d</file_size>", (int)sbuf.st_size);
return return_success(buf);
}
// always generates an HTML reply
//
int handle_request(FILE* in, R_RSA_PUBLIC_KEY& key) {
char buf[256];
char file_name[256];
int major, minor, release, retval=0;
bool got_version = true;
bool did_something = false;
double start_time = dtime();
#ifdef _USING_FCGI_
log_messages.set_indent_level(1);
#endif
while (fgets(buf, 256, in)) {
log_messages.printf(MSG_DEBUG, "handle_request: %s", buf);
if (parse_int(buf, "<core_client_major_version>", major)) {
continue;
} else if (parse_int(buf, "<core_client_minor_version>", minor)) {
continue;
} else if (parse_int(buf, "<core_client_release>", release)) {
continue;
} else if (match_tag(buf, "<file_upload>")) {
if (!got_version) {
retval = return_error(ERR_PERMANENT, "Missing version");
} else {
retval = handle_file_upload(in, key);
}
did_something = true;
break;
} else if (parse_str(buf, "<get_file_size>", file_name, sizeof(file_name))) {
if (strstr(file_name, "..")) {
return return_error(ERR_PERMANENT, "Bad filename");
}
if (!got_version) {
retval = return_error(ERR_PERMANENT, "Missing version");
} else {
retval = handle_get_file_size(file_name);
}
did_something = true;
break;
} else if (match_tag(buf, "<data_server_request>")) {
// DO NOTHING
} else {
log_messages.printf(MSG_DEBUG, "handle_request: unrecognized %s\n", buf);
}
}
if (!did_something) {
log_messages.printf(MSG_CRITICAL, "handle_request: no command\n");
return return_error(ERR_TRANSIENT, "no command");
}
log_messages.printf(MSG_DEBUG, "elapsed time %f seconds\n", dtime()-start_time);
return retval;
}
int get_key(R_RSA_PUBLIC_KEY& key) {
int retval;
char buf[256];
sprintf(buf, "%s/upload_public", config.key_dir);
#ifndef _USING_FCGI_
FILE *f = fopen(buf, "r");
#else
FCGI_FILE *f = FCGI::fopen(buf, "r");
#endif
if (!f) return -1;
#ifdef _USING_FCGI_
retval = scan_key_hex(FCGI_ToFILE(f), (KEY*)&key, sizeof(key));
#else
retval = scan_key_hex(f, (KEY*)&key, sizeof(key));
#endif
fclose(f);
if (retval) return retval;
return 0;
}
void boinc_catch_signal(int signal_num) {
char buffer[512]="";
if (this_filename[0]) {
sprintf(buffer, "FILE=%s (%.0f bytes left) ", this_filename, bytes_left);
}
log_messages.printf(MSG_CRITICAL,
"%sIP=%s caught signal %d [%s]\n",
buffer, get_remote_addr(),
signal_num, strsignal(signal_num)
);
// there is no point in trying to return an error.
// At this point Apache has broken the connection
// so a write to stdout will just generate a SIGPIPE
//
// return_error(ERR_TRANSIENT, "while downloading %s server caught signal %d", this_filename, signal_num);
_exit(1);
}
void installer() {
signal(SIGHUP, boinc_catch_signal); // terminal line hangup
signal(SIGINT, boinc_catch_signal); // interrupt program
signal(SIGQUIT, boinc_catch_signal); // quit program
signal(SIGILL, boinc_catch_signal); // illegal instruction
signal(SIGTRAP, boinc_catch_signal); // illegal instruction
signal(SIGABRT, boinc_catch_signal); // abort(2) call
signal(SIGFPE, boinc_catch_signal); // bus error
signal(SIGKILL, boinc_catch_signal); // bus error
signal(SIGBUS, boinc_catch_signal); // bus error
signal(SIGSEGV, boinc_catch_signal); // segmentation violation
signal(SIGSYS, boinc_catch_signal); // system call given invalid argument
signal(SIGPIPE, boinc_catch_signal); // write on a pipe with no reader
signal(SIGTERM, boinc_catch_signal); // terminate process
}
void usage(char *name) {
fprintf(stderr,
"This is the BOINC file upload handler.\n"
"It receives the results from the clients\n"
"and puts them on the file server.\n\n"
"Normally this is run as a CGI program.\n\n"
"Usage: %s [OPTION]...\n\n"
"Options:\n"
" [ -h | --help ] Show this help text.\n"
" [ -v | --version ] Show version information.\n",
name
);
}
int main(int argc, char *argv[]) {
int retval;
R_RSA_PUBLIC_KEY key;
char log_path[MAXPATHLEN];
#ifdef _USING_FCGI_
unsigned int counter=0;
#endif
for(int c = 1; c < argc; c++) {
string option(argv[c]);
if(option == "-v" || option == "--version") {
printf("%s\n", SVN_VERSION);
exit(0);
} else if(option == "-h" || option == "--help") {
usage(argv[0]);
exit(0);
} else if (option.length()){
fprintf(stderr, "unknown command line argument: %s\n\n", argv[c]);
usage(argv[0]);
exit(1);
}
}
installer();
get_log_path(log_path, "file_upload_handler.log");
#ifndef _USING_FCGI_
if (!freopen(log_path, "a", stderr)) {
fprintf(stderr, "Can't open log file '%s' (errno: %d)\n",
log_path, errno
);
return_error(ERR_TRANSIENT, "can't open log file '%s' (errno: %d)",
log_path, errno
);
exit(1);
}
#else
FCGI_FILE *f = FCGI::fopen(log_path, "a");
if (f) {
log_messages.redirect(f);
} else {
fprintf(stderr, "Can't redirect FCGI log messages\n");
return_error(ERR_TRANSIENT, "can't open log file (FCGI)");
exit(1);
}
#endif
retval = config.parse_file();
if (retval) {
fprintf(stderr, "Can't parse config.xml: %s\n", boincerror(retval));
return_error(ERR_TRANSIENT,
"can't parse config file", log_path, errno
);
exit(1);
}
log_messages.pid = getpid();
log_messages.set_debug_level(config.fuh_debug_level);
#ifndef _USING_FCGI_
if (boinc_file_exists(config.project_path("stop_upload"))) {
return_error(ERR_TRANSIENT,
"File uploads are temporarily disabled."
);
exit(1);
}
#endif
if (!config.ignore_upload_certificates) {
retval = get_key(key);
if (retval) {
return_error(ERR_TRANSIENT, "can't read key file");
exit(1);
}
}
#ifdef _USING_FCGI_
while(FCGI_Accept() >= 0) {
counter++;
//fprintf(stderr, "file_upload_handler (FCGI): counter: %d\n", counter);
if (boinc_file_exists(config.project_path("stop_upload"))) {
return_error(ERR_TRANSIENT,
"File uploads are temporarily disabled."
);
continue;
}
log_messages.set_indent_level(0);
#endif
handle_request(stdin, key);
#ifdef _USING_FCGI_
// flush log for FCGI, otherwise it just buffers a lot
log_messages.flush();
}
// when exiting, write headers back to apache so it won't complain
// about "incomplete headers"
fprintf(stdout,"Content-type: text/plain\n\n");
#endif
return 0;
}
const char *BOINC_RCSID_470a0d4d11 = "$Id$";