boinc/sched/file_upload_handler.cpp

676 lines
20 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 <cstdio>
#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 "crypt.h"
#include "parse.h"
#include "util.h"
#include "error_numbers.h"
#include "filesys.h"
#include "sched_config.h"
#include "sched_util.h"
#ifdef _USING_FCGI_
#include "boinc_fcgi.h"
#endif
#include "sched_msgs.h"
#define ERR_TRANSIENT true
#define ERR_PERMANENT false
char this_filename[256];
struct FILE_INFO {
char name[256];
double max_nbytes;
char* xml_signature;
char* signed_xml;
int parse(FILE*);
};
int FILE_INFO::parse(FILE* in) {
char buf[256];
int retval;
memset(this, 0, sizeof(FILE_INFO));
signed_xml = strdup("");
while (fgets(buf, 256, in)) {
//log_messages.printf(MSG_DEBUG, buf, "FILE_INFO::parse: ");
if (match_tag(buf, "</file_info>")) return 0;
if (match_tag(buf, "<xml_signature>")) {
retval = dup_element_contents(in, "</xml_signature>", &xml_signature);
if (retval) return retval;
continue;
}
retval = strcatdup(signed_xml, buf);
if (retval) return retval;
if (parse_str(buf, "<name>", name, sizeof(name))) {
strcpy(this_filename, name);
continue;
}
if (parse_double(buf, "<max_nbytes>", max_nbytes)) continue;
if (match_tag(buf, "<generated_locally/>")) continue;
if (match_tag(buf, "<upload_when_present/>")) continue;
if (match_tag(buf, "<url>")) continue;
if (match_tag(buf, "<gzip_when_done")) continue;
log_messages.printf(MSG_NORMAL,
"FILE_INFO::parse: unrecognized: %s \n", buf
);
}
return ERR_XML_PARSE;
}
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 16382
double bytes_left=-1;
// 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;
// open file. 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.
//
int fd = open(path,
O_WRONLY|O_CREAT|O_APPEND,
S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH
);
if (fd<0) {
return return_error(ERR_TRANSIENT,
"can't open file %s: %s\n", path, strerror(errno)
);
}
// Put an advisory lock on the file.
// This will prevent OTHER instances of file_upload_handler
// from being able to write to the file.
//
if ((pid=mylockf(fd))) {
close(fd);
return return_error(ERR_TRANSIENT,
"can't lock file %s: %s locked by PID=%d\n",
path, strerror(errno), pid
);
}
// 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 (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
);
}
// 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);
// 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[512], temp[256];
FILE_INFO file_info;
int retval;
double nbytes=-1, offset=0;
bool is_valid;
while (fgets(buf, 256, in)) {
#if 0
log_messages.printf(MSG_NORMAL, "got:%s\n", buf);
#endif
if (match_tag(buf, "<file_info>")) {
retval = file_info.parse(in);
if (retval) {
return return_error(ERR_PERMANENT, "FILE_INFO::parse");
}
#if 0
log_messages.printf(MSG_NORMAL,
"file info:\n%s\n", file_info.signed_xml
);
#endif
if (!config.ignore_upload_certificates) {
if (!file_info.signed_xml || !file_info.xml_signature) {
log_messages.printf(MSG_CRITICAL,
"file info is missing signature\n"
);
return return_error(ERR_PERMANENT, "invalid signature");
} else {
retval = verify_string(
file_info.signed_xml, file_info.xml_signature, key, is_valid
);
if (retval || !is_valid) {
log_messages.printf(MSG_CRITICAL,
"verify_string() [%s] [%s] retval %d, is_valid = %d\n",
file_info.signed_xml, file_info.xml_signature,
retval, is_valid
);
log_messages.printf(MSG_NORMAL,
"signed xml: %s", file_info.signed_xml
);
log_messages.printf(MSG_NORMAL,
"signature: %s", file_info.xml_signature
);
return return_error(ERR_PERMANENT, "invalid signature");
}
}
}
continue;
}
if (parse_double(buf, "<offset>", offset)) continue;
if (parse_double(buf, "<nbytes>", nbytes)) continue;
if (parse_str(buf, "<md5_cksum>", temp, sizeof(temp))) continue;
if (match_tag(buf, "<data>")) {
if (nbytes <= 0) {
return return_error(ERR_PERMANENT, "nbytes missing or negative");
}
// enforce limits in signed XML
//
if (!config.ignore_upload_certificates) {
if (nbytes > file_info.max_nbytes) {
sprintf(buf,
"file size (%d KB) exceeds limit (%d KB)",
(int)(nbytes/1024), (int)(file_info.max_nbytes/1024)
);
copy_socket_to_null(in);
return return_error(ERR_PERMANENT, buf);
}
}
// make sure filename is legit
//
if (strstr(file_info.name, "..")) {
return return_error(ERR_PERMANENT,
"file_upload_handler: .. found in filename: %s",
file_info.name
);
}
if (strlen(file_info.name) == 0) {
return return_error(ERR_PERMANENT,
"file_upload_handler: no filename; nbytes %f", nbytes
);
}
retval = dir_hier_path(
file_info.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",
file_info.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",
file_info.name,
get_remote_addr(),
offset, nbytes
);
#ifndef _USING_FCGI_
fflush(stderr);
#endif
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",
file_info.name,
get_remote_addr(),
retval
);
#ifndef _USING_FCGI_
fflush(stderr);
#endif
return retval;
}
log_messages.printf(MSG_CRITICAL,
"unrecognized: %s", buf
);
}
return return_error(ERR_PERMANENT, "Missing <data> tag");
}
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[512], 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;
#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", elapsed_wallclock_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;
retval = scan_key_hex(f, (KEY*)&key, sizeof(key));
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] elapsed time %f seconds\n",
buffer, get_remote_addr(),
signal_num, strsignal(signal_num), elapsed_wallclock_time()
);
// 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
}
int main() {
int retval;
R_RSA_PUBLIC_KEY key;
char log_path[256];
#ifdef _USING_FCGI_
unsigned int counter=0;
#endif
elapsed_wallclock_time();
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\n");
return_error(ERR_TRANSIENT, "can't open log file");
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) {
exit(1);
}
log_messages.pid = getpid();
log_messages.set_debug_level(config.fuh_debug_level);
if (boinc_file_exists("../stop_upload")) {
return_error(ERR_TRANSIENT, "Maintenance underway: file uploads are temporarily disabled.");
exit(1);
}
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);
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 = "$Id$";