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// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "debug.h"
#include "sandbox_impl.h"
namespace playground {
int Sandbox::sandbox_stat(const char *path, void *buf) {
Debug::syscall(__NR_stat, "Executing handler");
size_t len = strlen(path);
struct Request {
int sysnum;
long long cookie;
Stat stat_req;
char pathname[0];
} __attribute__((packed)) *request;
char data[sizeof(struct Request) + len];
request = reinterpret_cast<struct Request*>(data);
request->sysnum = __NR_stat;
request->cookie = cookie();
request->stat_req.sysnum = __NR_stat;
request->stat_req.path_length = len;
request->stat_req.buf = buf;
memcpy(request->pathname, path, len);
long rc;
SysCalls sys;
if (write(sys, processFdPub(), request, sizeof(data)) != (int)sizeof(data) ||
read(sys, threadFdPub(), &rc, sizeof(rc)) != sizeof(rc)) {
die("Failed to forward stat() request [sandbox]");
}
return static_cast<int>(rc);
}
int Sandbox::sandbox_lstat(const char *path, void *buf) {
Debug::syscall(__NR_lstat, "Executing handler");
size_t len = strlen(path);
struct Request {
int sysnum;
long long cookie;
Stat stat_req;
char pathname[0];
} __attribute__((packed)) *request;
char data[sizeof(struct Request) + len];
request = reinterpret_cast<struct Request*>(data);
request->sysnum = __NR_lstat;
request->cookie = cookie();
request->stat_req.sysnum = __NR_lstat;
request->stat_req.path_length = len;
request->stat_req.buf = buf;
memcpy(request->pathname, path, len);
long rc;
SysCalls sys;
if (write(sys, processFdPub(), request, sizeof(data)) != (int)sizeof(data) ||
read(sys, threadFdPub(), &rc, sizeof(rc)) != sizeof(rc)) {
die("Failed to forward lstat() request [sandbox]");
}
return static_cast<int>(rc);
}
#if defined(__NR_stat64)
int Sandbox::sandbox_stat64(const char *path, void *buf) {
Debug::syscall(__NR_stat64, "Executing handler");
size_t len = strlen(path);
struct Request {
int sysnum;
long long cookie;
Stat stat_req;
char pathname[0];
} __attribute__((packed)) *request;
char data[sizeof(struct Request) + len];
request = reinterpret_cast<struct Request*>(data);
request->sysnum = __NR_stat64;
request->cookie = cookie();
request->stat_req.sysnum = __NR_stat64;
request->stat_req.path_length = len;
request->stat_req.buf = buf;
memcpy(request->pathname, path, len);
long rc;
SysCalls sys;
if (write(sys, processFdPub(), request, sizeof(data)) != (int)sizeof(data) ||
read(sys, threadFdPub(), &rc, sizeof(rc)) != sizeof(rc)) {
die("Failed to forward stat64() request [sandbox]");
}
return static_cast<int>(rc);
}
int Sandbox::sandbox_lstat64(const char *path, void *buf) {
Debug::syscall(__NR_lstat64, "Executing handler");
size_t len = strlen(path);
struct Request {
int sysnum;
long long cookie;
Stat stat_req;
char pathname[0];
} __attribute__((packed)) *request;
char data[sizeof(struct Request) + len];
request = reinterpret_cast<struct Request*>(data);
request->sysnum = __NR_lstat64;
request->cookie = cookie();
request->stat_req.sysnum = __NR_lstat64;
request->stat_req.path_length = len;
request->stat_req.buf = buf;
memcpy(request->pathname, path, len);
long rc;
SysCalls sys;
if (write(sys, processFdPub(), request, sizeof(data)) != (int)sizeof(data) ||
read(sys, threadFdPub(), &rc, sizeof(rc)) != sizeof(rc)) {
die("Failed to forward lstat64() request [sandbox]");
}
return static_cast<int>(rc);
}
#endif
bool Sandbox::process_stat(int parentMapsFd, int sandboxFd, int threadFdPub,
int threadFd, SecureMem::Args* mem) {
// Read request
SysCalls sys;
Stat stat_req;
if (read(sys, sandboxFd, &stat_req, sizeof(stat_req)) != sizeof(stat_req)) {
read_parm_failed:
die("Failed to read parameters for stat() [process]");
}
int rc = -ENAMETOOLONG;
if (stat_req.path_length >= (int)sizeof(mem->pathname)) {
char buf[32];
while (stat_req.path_length > 0) {
size_t len = stat_req.path_length > sizeof(buf) ?
sizeof(buf) : stat_req.path_length;
ssize_t i = read(sys, sandboxFd, buf, len);
if (i <= 0) {
goto read_parm_failed;
}
stat_req.path_length -= i;
}
if (write(sys, threadFd, &rc, sizeof(rc)) != sizeof(rc)) {
die("Failed to return data from stat() [process]");
}
return false;
}
// We implement a strict policy of denying all file accesses
char tmp[stat_req.path_length + 1];
if (read(sys, sandboxFd, tmp, stat_req.path_length) !=
(ssize_t)stat_req.path_length) {
goto read_parm_failed;
}
tmp[stat_req.path_length] = '\000';
Debug::message(("Denying access to \"" + std::string(tmp) + "\"").c_str());
SecureMem::abandonSystemCall(threadFd, -EACCES);
return false;
}
} // namespace
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