ladybird/Kernel/Syscalls/pledge.cpp
2020-08-02 10:56:43 +02:00

105 lines
3.5 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/StringView.h>
#include <Kernel/Process.h>
namespace Kernel {
int Process::sys$pledge(Userspace<const Syscall::SC_pledge_params*> user_params)
{
Syscall::SC_pledge_params params;
if (!validate_read_and_copy_typed(&params, user_params))
return -EFAULT;
if (params.promises.length > 1024 || params.execpromises.length > 1024)
return -E2BIG;
String promises;
if (params.promises.characters) {
promises = validate_and_copy_string_from_user(params.promises);
if (promises.is_null())
return -EFAULT;
}
String execpromises;
if (params.execpromises.characters) {
execpromises = validate_and_copy_string_from_user(params.execpromises);
if (execpromises.is_null())
return -EFAULT;
}
auto parse_pledge = [&](auto& pledge_spec, u32& mask) {
auto parts = pledge_spec.split_view(' ');
for (auto& part : parts) {
#define __ENUMERATE_PLEDGE_PROMISE(x) \
if (part == #x) { \
mask |= (1u << (u32)Pledge::x); \
continue; \
}
ENUMERATE_PLEDGE_PROMISES
#undef __ENUMERATE_PLEDGE_PROMISE
if (part == "dns") {
// "dns" is an alias for "unix" since DNS queries go via LookupServer
mask |= (1u << (u32)Pledge::unix);
continue;
}
return false;
}
return true;
};
u32 new_promises;
u32 new_execpromises;
if (!promises.is_null()) {
new_promises = 0;
if (!parse_pledge(promises, new_promises))
return -EINVAL;
if (m_promises && (!new_promises || new_promises & ~m_promises))
return -EPERM;
} else {
new_promises = m_promises;
}
if (!execpromises.is_null()) {
new_execpromises = 0;
if (!parse_pledge(execpromises, new_execpromises))
return -EINVAL;
if (m_execpromises && (!new_execpromises || new_execpromises & ~m_execpromises))
return -EPERM;
} else {
new_execpromises = m_execpromises;
}
m_promises = new_promises;
m_execpromises = new_execpromises;
return 0;
}
}