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#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);
}
#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);
}
#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;
}
SecureMem::lockSystemCall(parentMapsFd, mem);
if (read(sys, sandboxFd, mem->pathname, stat_req.path_length) !=
(ssize_t)stat_req.path_length) {
goto read_parm_failed;
}
mem->pathname[stat_req.path_length] = '\000';
// TODO(markus): Implement sandboxing policy
Debug::message(("Allowing access to \"" + std::string(mem->pathname) +
"\"").c_str());
// Tell trusted thread to stat the file.
SecureMem::sendSystemCall(threadFdPub, true, parentMapsFd, mem,
#if defined(__i386__)
stat_req.sysnum == __NR_stat64 ? __NR_stat64 :
#endif
__NR_stat,
mem->pathname - (char*)mem + (char*)mem->self,
stat_req.buf);
return true;
}
} // namespace
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