/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/assert.h"
#include "libc/bits/bits.h"
#include "libc/bits/weaken.h"
#include "libc/calls/ioctl.h"
#include "libc/calls/strace.internal.h"
#include "libc/calls/syscall-sysv.internal.h"
#include "libc/macros.internal.h"
#include "libc/mem/mem.h"
#include "libc/sock/internal.h"
#include "libc/sock/sock.h"
#include "libc/sock/struct/ifconf.h"
#include "libc/sock/struct/ifreq.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/af.h"
#include "libc/sysv/consts/sio.h"
#include "libc/sysv/errfuns.h"
/* SIOCGIFCONF:
* Takes an struct ifconf object of a given size
* Modifies the following:
* - ifc_len: set it to the number of valid ifreq structures representing
* the interfaces
* - ifc_ifcu.ifcu_req: sets the name of the interface for each interface
* The ifc_len is an input/output parameter: set it to the total size of
* the ifcu_buf (ifcu_req) buffer on input.
*/
int ioctl_siocgifconf_nt(int, struct ifconf *) hidden;
int ioctl_siocgifaddr_nt(int, struct ifreq *) hidden;
int ioctl_siocgifflags_nt(int, struct ifreq *) hidden;
int ioctl_siocgifnetmask_nt(int, struct ifreq *) hidden;
int ioctl_siocgifbrdaddr_nt(int, struct ifreq *) hidden;
static int ioctl_siocgifconf_sysv(int fd, struct ifconf *ifc) {
/*
* We're 100% compatible with Linux.
* BSD ABIs mainly differ by having sockaddr::sa_len
* XNU uses a 32-bit length in a struct that's packed!
*/
int i, rc, fam;
char *b, *p, *e;
char ifcBsd[16];
struct ifreq *req;
struct ifreq *end;
uint32_t bufLen, ip;
size_t numReq, bufMax;
if (IsLinux()) return sys_ioctl(fd, SIOCGIFCONF, ifc);
if (!weaken(malloc)) return enomem();
bufMax = 15000; /* conservative guesstimate */
if (!(b = weaken(malloc)(bufMax))) return enomem();
memcpy(ifcBsd, &bufMax, 8); /* ifc_len */
memcpy(ifcBsd + (IsXnu() ? 4 : 8), &b, 8); /* ifc_buf */
if ((rc = sys_ioctl(fd, SIOCGIFCONF, &ifcBsd)) != -1) {
/*
* On XNU the size of the struct ifreq is different than Linux.
* On Linux is fixed (40 bytes), but on XNU the struct sockaddr
* has variable length, making the whole struct ifreq a variable
* sized record.
*/
memcpy(&bufLen, b, 4);
req = ifc->ifc_req;
end = req + ifc->ifc_len / sizeof(*req);
for (p = b, e = p + MIN(bufMax, READ32LE(ifcBsd)); p + 16 + 16 <= e;
p += IsBsd() ? 16 + MAX(16, p[16] & 255) : 40) {
fam = p[IsBsd() ? 17 : 16] & 255;
if (fam != AF_INET) continue;
ip = READ32BE(p + 20);
bzero(req, sizeof(*req));
memcpy(req->ifr_name, p, 16);
memcpy(&req->ifr_addr, p + 16, 16);
req->ifr_addr.sa_family = fam;
((struct sockaddr_in *)&req->ifr_addr)->sin_addr.s_addr = htonl(ip);
++req;
}
ifc->ifc_len = (char *)req - ifc->ifc_buf; /* Adjust len */
}
if (weaken(free)) weaken(free)(b);
return rc;
}
forceinline void Sockaddr2linux(void *saddr) {
char *p;
if (saddr) {
p = saddr;
p[0] = p[1];
p[1] = 0;
}
}
/* Used for all the ioctl that returns sockaddr structure that
* requires adjustment between Linux and XNU
*/
static int ioctl_siocgifaddr_sysv(int fd, uint64_t op, struct ifreq *ifr) {
if (sys_ioctl(fd, op, ifr) == -1) return -1;
if (IsBsd()) Sockaddr2linux(&ifr->ifr_addr);
return 0;
}
/**
* Returns information about network interfaces.
*
* @see ioctl(fd, SIOCGIFCONF, tio) dispatches here
*/
int ioctl_siocgifconf(int fd, ...) {
int rc;
va_list va;
struct ifconf *ifc;
va_start(va, fd);
ifc = va_arg(va, struct ifconf *);
va_end(va);
if (!IsWindows()) {
rc = ioctl_siocgifconf_sysv(fd, ifc);
} else {
rc = ioctl_siocgifconf_nt(fd, ifc);
}
STRACE("%s(%d) → %d% m", "ioctl_siocgifconf", fd, rc);
return rc;
}
int ioctl_siocgifaddr(int fd, ...) {
va_list va;
struct ifreq *ifr;
va_start(va, fd);
ifr = va_arg(va, struct ifreq *);
va_end(va);
if (!IsWindows()) {
return ioctl_siocgifaddr_sysv(fd, SIOCGIFADDR, ifr);
} else {
return ioctl_siocgifaddr_nt(fd, ifr);
}
}
int ioctl_siocgifnetmask(int fd, ...) {
va_list va;
struct ifreq *ifr;
va_start(va, fd);
ifr = va_arg(va, struct ifreq *);
va_end(va);
if (!IsWindows()) {
return ioctl_siocgifaddr_sysv(fd, SIOCGIFNETMASK, ifr);
} else {
return ioctl_siocgifnetmask_nt(fd, ifr);
}
}
int ioctl_siocgifbrdaddr(int fd, ...) {
va_list va;
struct ifreq *ifr;
va_start(va, fd);
ifr = va_arg(va, struct ifreq *);
va_end(va);
if (!IsWindows()) {
return ioctl_siocgifaddr_sysv(fd, SIOCGIFBRDADDR, ifr);
} else {
return ioctl_siocgifbrdaddr_nt(fd, ifr);
}
}
int ioctl_siocgifdstaddr(int fd, ...) {
va_list va;
struct ifreq *ifr;
va_start(va, fd);
ifr = va_arg(va, struct ifreq *);
va_end(va);
if (!IsWindows()) {
return ioctl_siocgifaddr_sysv(fd, SIOCGIFDSTADDR, ifr);
} else {
return enotsup();
/* Not supported - Unknown how to find out how to retrieve the destination
* address of a PPP from the interface list returned by the
* GetAdaptersAddresses function
*
return ioctl_siocgifdstaddr_nt(fd, ifc);
*/
}
}
int ioctl_siocgifflags(int fd, ...) {
va_list va;
struct ifreq *ifr;
va_start(va, fd);
ifr = va_arg(va, struct ifreq *);
va_end(va);
if (!IsWindows()) {
/* Both XNU and Linux are for once compatible here... */
return ioctl_default(fd, SIOCGIFFLAGS, ifr);
} else {
return ioctl_siocgifflags_nt(fd, ifr);
}
}