AuroraRuntime/Source/IO/Net/AuNetAdapter.Linux.cpp
J Reece Wilson 9ce314a838 [*] Linux DirMks shall copy the stat of the parent dir before assuming 775.
[*] Added missing null allocation checks under linux net adapter list
2022-12-17 15:37:46 +00:00

519 lines
14 KiB
C++

/***
Copyright (C) 2022 J Reece Wilson (a/k/a "Reece"). All rights reserved.
File: AuNetAdapter.Linux.cpp
Date: 2022-11-15
Author: Reece
***/
#include "Networking.hpp"
#include "AuNetAdapter.hpp"
#include "AuNetEndpoint.hpp"
#include <asm/types.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <sys/socket.h>
namespace Aurora::IO::Net
{
AuString NetAdapter::GetHostname()
{
char name[128];
if (::gethostname(name, AuArraySize(name)) != 0)
{
return "";
}
return name;
}
// Based on https://gist.github.com/Yawning/c70d804d4b8ae78cc698
struct NetlinkDevice
{
NetlinkDevice();
~NetlinkDevice();
bool Connect();
AuSInt Send(const void *pBuffer, size_t uLength);
AuSInt Recv(void *pBuffer, size_t uLength);
AuList<NetAdapter> GetAdaptersForFamily(sa_family_t family);
AuList<AuPair<int, NetEndpoint>> ReadRoutes(int index, int family, AuString &name);
void UpdateAdapterInfo(int family, NetAdapter &adapter);
int fd { -1 };
};
static NetlinkDevice gNetlinkDevice;
NetlinkDevice::NetlinkDevice()
{
}
NetlinkDevice::~NetlinkDevice()
{
if (this->fd != -1)
{
::close(this->fd);
}
}
bool NetlinkDevice::Connect()
{
sockaddr_nl nladdr {};
this->fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
if (this->fd < 0)
{
return false;
}
int flags = ::fcntl(this->fd, F_GETFL, 0);
if (flags != -1)
{
::fcntl(this->fd, F_SETFL, flags | FD_CLOEXEC);
}
nladdr.nl_family = AF_NETLINK;
if (::bind(this->fd, (struct sockaddr *) &nladdr, sizeof(nladdr)) != 0)
{
return false;
}
return true;
}
AuSInt NetlinkDevice::Send(const void *pBuffer, size_t uLength)
{
sockaddr_nl nladdr {};
msghdr msg {};
iovec vec {};
nladdr.nl_family = AF_NETLINK;
msg.msg_name = &nladdr;
msg.msg_namelen = sizeof(nladdr);
vec.iov_base = (char *)pBuffer;
vec.iov_len = uLength;
msg.msg_iov = &vec;
msg.msg_iovlen = 1;
return ::sendmsg(fd, &msg, 0);
}
AuSInt NetlinkDevice::Recv(void *pBuffer, size_t uLength)
{
sockaddr_nl nladdr {};
msghdr msg {};
iovec vec;
nladdr.nl_family = AF_NETLINK;
msg.msg_name = &nladdr;
msg.msg_namelen = sizeof(nladdr);
vec.iov_base = pBuffer;
vec.iov_len = uLength;
msg.msg_iov = &vec;
msg.msg_iovlen = 1;
auto ret = ::recvmsg(fd, &msg, 0);
if (msg.msg_flags & MSG_TRUNC)
{
return -1;
}
return ret;
}
struct addr_t
{
sa_family_t family;
union
{
in_addr in_addr;
in6_addr in6_addr;
} u;
};
AuList<NetAdapter> NetlinkDevice::GetAdaptersForFamily(sa_family_t family)
{
static const auto kRouteBufferSize = 12 * 1024;
struct nlmsghdr *hdr;
struct rtmsg *rt;
ssize_t len;
size_t reqlen;
reqlen = NLMSG_SPACE(sizeof(*rt));
auto pReq = AuMakeSharedArray<AuUInt8>(kRouteBufferSize);
if (!pReq)
{
SysPushErrorMemory();
return {};
}
hdr = (struct nlmsghdr *)pReq.get();
hdr->nlmsg_len = NLMSG_LENGTH(sizeof(*rt));
hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
hdr->nlmsg_type = RTM_GETROUTE;
rt = (struct rtmsg *)NLMSG_DATA(hdr);
rt->rtm_family = family;
rt->rtm_table = RT_TABLE_MAIN | RT_TABLE_LOCAL;
if (this->Send(pReq.get(), reqlen) < 0)
{
SysPushErrorIO("netlink error");
return {};
}
auto pResp = AuMakeSharedArray<AuUInt8>(kRouteBufferSize);
if (!pResp)
{
SysPushErrorMemory();
return {};
}
AuList<NetAdapter> ret;
while (1)
{
len = this->Recv(pResp.get(), kRouteBufferSize);
if (len < 0)
{
SysPushErrorIO("netlink error");
return {};
}
for (hdr = (struct nlmsghdr *)pResp.get();
NLMSG_OK(hdr, len);
hdr = NLMSG_NEXT(hdr, len))
{
NetAdapter adapter;
if (hdr->nlmsg_type == NLMSG_DONE)
{
return ret;
}
if (hdr->nlmsg_type == NLMSG_ERROR)
{
return {};
}
rt = (struct rtmsg *)NLMSG_DATA(hdr);
auto attr = RTM_RTA(rt);
auto attrlen = RTM_PAYLOAD(hdr);
for (; RTA_OK(attr, attrlen); attr = RTA_NEXT(attr, attrlen))
{
const size_t expectedAddressLength = (family == AF_INET) ? 4 : 16;
size_t dstlen = RTA_PAYLOAD(attr);
switch (attr->rta_type)
{
case RTA_GATEWAY:
case RTA_DST:
case RTA_SRC:
{
if (dstlen != expectedAddressLength)
{
continue;
}
NetEndpoint ep;
addr_t *address2 = (addr_t*)ep.hint;
address2->family = family;
AuMemcpy(&address2->u.in_addr, RTA_DATA(attr), dstlen);
DeoptimizeEndpoint(ep);
if (attr->rta_type == RTA_GATEWAY)
{
adapter.gateway = ep.ip;
}
if (attr->rta_type == RTA_DST)
{
adapter.address = ep.ip;
}
break;
}
case RTA_OIF:
{
adapter.index = *(int*)RTA_DATA(attr);
break;
}
default:
{
break;
}
}
}
ret.push_back(adapter);
}
}
return ret;
}
AuList<AuPair<int, NetEndpoint>> NetlinkDevice::ReadRoutes(int index, int family, AuString &name)
{
static const auto kAddrBufferSize = 12 * 1024;
AuList<AuPair<int, NetEndpoint>> ret;
nlmsghdr *hdr {};
ifaddrmsg *ifa {};
ssize_t len;
size_t reqlen;
/* Allocate space for the request. */
reqlen = NLMSG_SPACE(sizeof(*ifa));
auto pReq = AuMakeSharedArray<AuUInt8>(kAddrBufferSize);
if (!pReq)
{
SysPushErrorMemory();
return {};
}
hdr = (struct nlmsghdr *)pReq.get();
hdr->nlmsg_len = NLMSG_LENGTH(sizeof(*ifa));
hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ROOT;
hdr->nlmsg_type = RTM_GETADDR;
ifa = (struct ifaddrmsg *)NLMSG_DATA(hdr);
ifa->ifa_family = family;
ifa->ifa_index = index;
if (this->Send(pReq.get(), reqlen) < 0)
{
SysPushErrorIO("netlink error");
return {};
}
auto pResp = AuMakeSharedArray<AuUInt8>(kAddrBufferSize);
if (!pResp)
{
SysPushErrorMemory();
return {};
}
while (1)
{
len = this->Recv(pResp.get(), kAddrBufferSize);
if (len < 0)
{
SysPushErrorIO("netlink error");
return {};
}
for (hdr = (struct nlmsghdr *)pResp.get(); NLMSG_OK(hdr, len); hdr = NLMSG_NEXT(hdr, len))
{
if (hdr->nlmsg_type == NLMSG_DONE)
{
return ret;
}
if (hdr->nlmsg_type == NLMSG_ERROR)
{
return {};
}
ifa = (struct ifaddrmsg *)NLMSG_DATA(hdr);
if ((ifa->ifa_family != family) ||
(ifa->ifa_index != index))
{
continue;
}
if (ifa->ifa_scope != RT_SCOPE_UNIVERSE)
{
continue;
}
auto attr = IFA_RTA(ifa);
auto attrlen = RTM_PAYLOAD(hdr);
for (; RTA_OK(attr, attrlen); attr = RTA_NEXT(attr, attrlen))
{
size_t dstlen = RTA_PAYLOAD(attr);
const size_t addrlen = (family == AF_INET) ? sizeof(struct in_addr) : sizeof(struct in6_addr);
if (attr->rta_type == IFA_LABEL)
{
name = (const char *)RTA_DATA(attr);
}
else if (addrlen == dstlen)
{
NetEndpoint ep;
addr_t *address2 = (addr_t*)ep.hint;
address2->family = family;
AuMemcpy(&address2->u.in_addr, RTA_DATA(attr), addrlen);
DeoptimizeEndpoint(ep);
ret.push_back(AuMakePair(attr->rta_type, ep));
}
}
}
}
return ret;
}
void NetlinkDevice::UpdateAdapterInfo(int family, NetAdapter &adapter)
{
static const auto kAddrBufferSize = 12 * 1024;
nlmsghdr *hdr {};
ifinfomsg *ifa {};
auto reqlen = NLMSG_SPACE(sizeof(*ifa));
auto pReq = AuMakeSharedArray<AuUInt8>(kAddrBufferSize);
if (!pReq)
{
SysPushErrorMemory();
return;
}
hdr = (struct nlmsghdr *)pReq.get();
hdr->nlmsg_len = NLMSG_LENGTH(sizeof(*ifa));
hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
hdr->nlmsg_type = RTM_GETLINK;
ifa = (struct ifinfomsg *)NLMSG_DATA(hdr);
ifa->ifi_family = family;
ifa->ifi_index = adapter.index;
if (this->Send(pReq.get(), reqlen) < 0)
{
SysPushErrorIO("netlink error");
return;
}
auto pResp = AuMakeSharedArray<AuUInt8>(kAddrBufferSize);
if (!pResp)
{
SysPushErrorMemory();
return ;
}
while (1)
{
auto len = this->Recv(pResp.get(), kAddrBufferSize);
if (len < 0)
{
SysPushErrorIO("netlink error");
return;
}
for (hdr = (struct nlmsghdr *)pResp.get(); NLMSG_OK(hdr, len); hdr = NLMSG_NEXT(hdr, len))
{
if (hdr->nlmsg_type == NLMSG_DONE)
{
return;
}
if (hdr->nlmsg_type == NLMSG_ERROR)
{
return;
}
ifa = (struct ifinfomsg *)NLMSG_DATA(hdr);
if ((ifa->ifi_index != adapter.index))
{
continue;
}
auto attr = IFLA_RTA(ifa);
auto attrlen = hdr->nlmsg_len - NLMSG_LENGTH(sizeof(*ifa));
for (; RTA_OK(attr, attrlen); attr = RTA_NEXT(attr, attrlen)) {
size_t dstlen = RTA_PAYLOAD(attr);
const size_t addrlen = (family == AF_INET) ? sizeof(struct in_addr) : sizeof(struct in6_addr);
if (attr->rta_type == IFLA_IFNAME)
{
adapter.device = (const char *)RTA_DATA(attr);
}
// TODO: we can pull MTU and other stats from here.
}
}
}
}
static AuList<AuSPtr<INetAdapter>> GetForFamily(int family)
{
AuList<AuSPtr<INetAdapter>> ret;
if (gNetlinkDevice.fd == -1)
{
if (!gNetlinkDevice.Connect())
{
return {};
}
}
AuList<IPAddress> dups;
auto adapters = gNetlinkDevice.GetAdaptersForFamily(family);
for (auto &adapter : adapters)
{
gNetlinkDevice.UpdateAdapterInfo(family, adapter);
auto pAdapter = AuMakeShared<NetAdapter>(adapter);
if (!pAdapter)
{
SysPushErrorMemory();
return {};
}
bool bBreak = false;
auto ips = gNetlinkDevice.ReadRoutes(adapter.index, family, pAdapter->name);
for (const auto &[type, endpoint] : ips)
{
if (type == IFA_ANYCAST)
{
pAdapter->anycast = endpoint.ip;
}
if (type == IFA_ADDRESS)
{
bBreak |= AuExists(dups, endpoint.ip);
dups.push_back(endpoint.ip);
pAdapter->address = endpoint.ip;
}
if (type == IFA_BROADCAST)
{
pAdapter->broadcast = endpoint.ip;
}
}
if (bBreak)
{
continue;
}
ret.push_back(pAdapter);
}
return ret;
}
AuList<AuSPtr<INetAdapter>> NetAdapter::GetIPv4s()
{
return GetForFamily(AF_INET);
}
AuList<AuSPtr<INetAdapter>> NetAdapter::GetIPv6s()
{
return GetForFamily(AF_INET6);
}
}