strace/sock.c

/*
 * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
 * Copyright (c) 1996-2018 The strace developers.
 * All rights reserved.
 *
 * SPDX-License-Identifier: LGPL-2.1-or-later
 */

#include "defs.h"
#include "print_fields.h"

#include <sys/socket.h>
#if defined ALPHA || defined SH || defined SH64
# include <linux/ioctl.h>
#endif
#include <linux/sockios.h>
#include <arpa/inet.h>
#include <net/if.h>

#include DEF_MPERS_TYPE(struct_ifconf)
#include DEF_MPERS_TYPE(struct_ifreq)

typedef struct ifconf struct_ifconf;
typedef struct ifreq struct_ifreq;

#include MPERS_DEFS

#include "xlat/iffflags.h"

#define XLAT_MACROS_ONLY
#include "xlat/arp_hardware_types.h"
#undef XLAT_MACROS_ONLY

static void
print_ifname(const char *ifname)
{
	print_quoted_string(ifname, IFNAMSIZ + 1, QUOTE_0_TERMINATED);
}

DIAG_PUSH_IGNORE_OVERRIDE_INIT

static void
print_ifreq(struct tcb *const tcp, const unsigned int code,
	    const kernel_ulong_t arg, const struct_ifreq *const ifr)
{
	switch (code) {
	case SIOCSIFADDR:
	case SIOCGIFADDR:
		PRINT_FIELD_SOCKADDR("", *ifr, ifr_addr);
		break;
	case SIOCSIFDSTADDR:
	case SIOCGIFDSTADDR:
		PRINT_FIELD_SOCKADDR("", *ifr, ifr_dstaddr);
		break;
	case SIOCSIFBRDADDR:
	case SIOCGIFBRDADDR:
		PRINT_FIELD_SOCKADDR("", *ifr, ifr_broadaddr);
		break;
	case SIOCSIFNETMASK:
	case SIOCGIFNETMASK:
		PRINT_FIELD_SOCKADDR("", *ifr, ifr_netmask);
		break;
	case SIOCSIFHWADDR:
	case SIOCGIFHWADDR: {
		static uint8_t hwaddr_sizes[] = {
			[0 ... ARPHRD_IEEE802_TR] = 255,

			[ARPHRD_NETROM]     =  7 /* AX25_ADDR_LEN */,
			[ARPHRD_ETHER]      =  6 /* ETH_ALEN */,
			/* ARPHRD_EETHER - no actual devices in Linux */
			[ARPHRD_AX25]       =  7 /* AX25_ADDR_LEN */,
			/* ARPHRD_PRONET - no actual devices in Linux */
			/* ARPHRD_CHAOS - no actual devices in Linux */
			[ARPHRD_IEEE802]    =  6 /* FC_ALEN */,
			[ARPHRD_ARCNET]     =  1 /* ARCNET_ALEN */,
			/* ARPHRD_APPLETLK - no actual devices in Linux */
			[ARPHRD_DLCI]       = sizeof(short),
			/* ARPHRD_ATM - no explicit setting */
			/* ARPHRD_METRICOM - no actual devices in Linux */
			[ARPHRD_IEEE1394]   = 16 /* FWNET_ALEN */,
			[ARPHRD_EUI64]      =  8 /* EUI64_ADDR_LEN */,
			[ARPHRD_INFINIBAND] = 20 /* INFINIBAND_ALEN */,
			[ARPHRD_SLIP]       =  0,
			/* ARPHRD_CSLIP - no actual devices in Linux */
			/* ARPHRD_SLIP6 - no actual devices in Linux */
			/* ARPHRD_CSLIP6 - no actual devices in Linux */
			/* ARPHRD_RSRVD - no actual devices in Linux */
			/* ARPHRD_ADAPT - no actual devices in Linux */
			[ARPHRD_ROSE]       =  5 /* ROSE_ADDR_LEN */,
			[ARPHRD_X25]        =  0,
			/* ARPHRD_HWX25 - no actual devices in Linux */
			[ARPHRD_CAN]        =  0,
			[ARPHRD_PPP]        =  0,
			/* ARPHRD_CISCO - no actual devices in Linux */
			/* ARPHRD_LAPB - no actual devices in Linux */
			/* ARPHRD_DDCMP - no actual devices in Linux */
			[ARPHRD_RAWHDLC]    =  0,
			[ARPHRD_RAWIP]      =  0,
			[ARPHRD_TUNNEL]     =  4 /* IPIP */,
			[ARPHRD_TUNNEL6]    = 16 /* sizeof(struct in6_addr) */,
			/* ARPHRD_FRAD - no actual devices in Linux */
			/* ARPHRD_SKIP - no actual devices in Linux */
			[ARPHRD_LOOPBACK]   =  6 /* ETH_ALEN */,
			[ARPHRD_LOCALTLK]   =  1 /* LTALK_ALEN */,
			[ARPHRD_FDDI]       =  6 /* FDDI_K_ALEN */,
			/* ARPHRD_BIF - no actual devices in Linux */
			[ARPHRD_SIT]        =  4,
			[ARPHRD_IPDDP]      =  0,
			[ARPHRD_IPGRE]      =  4,
			[ARPHRD_PIMREG]     =  0,
			[ARPHRD_HIPPI]      =  6 /* HIPPI_ALEN */,
			/* ARPHRD_ASH - no actual devices in Linux */
			/* ARPHRD_ECONET - no actual devices in Linux */
			[ARPHRD_IRDA]       =  4 /* LAP_ALEN */,
			/* ARPHRD_FCPP - no actual devices in Linux */
			/* ARPHRD_FCAL - no actual devices in Linux */
			/* ARPHRD_FCPL - no actual devices in Linux */
			/* ARPHRD_FCFABRIC - no actual devices in Linux */
			/* ARPHRD_IEEE802_TR - no actual devices in Linux */
			[ARPHRD_IEEE80211]  =  6 /* ETH_ALEN */,
			[ARPHRD_IEEE80211_PRISM] = 6 /* ETH_ALEN */,
			[ARPHRD_IEEE80211_RADIOTAP] = 6 /* ETH_ALEN */,
			[ARPHRD_IEEE802154]
				= 8 /* IEEE802154_EXTENDED_ADDR_LEN */,
			[ARPHRD_IEEE802154_MONITOR]
				= 8 /* IEEE802154_EXTENDED_ADDR_LEN */,
			[ARPHRD_PHONET]     =  1,
			[ARPHRD_PHONET_PIPE] = 1,
			[ARPHRD_CAIF]       =  0,
			[ARPHRD_IP6GRE]     = 16 /* sizeof(struct in6_addr) */,
			[ARPHRD_NETLINK]    =  0,
			[ARPHRD_6LOWPAN]    =  8 /* EUI64_ADDR_LEN */
				/* ^ or ETH_ALEN, depending on lltype */,
			[ARPHRD_VSOCKMON]   =  0,
		};

		uint16_t proto = ifr->ifr_hwaddr.sa_family;
		uint8_t sz = (proto < ARRAY_SIZE(hwaddr_sizes))
				? hwaddr_sizes[proto] : 255;

		PRINT_FIELD_XVAL_SORTED_SIZED("ifr_hwaddr={", ifr->ifr_hwaddr,
					      sa_family, arp_hardware_types,
					      arp_hardware_types_size,
					      "ARPHRD_???");
		PRINT_FIELD_MAC_SZ(", ", ifr->ifr_hwaddr, sa_data,
				   MIN(sizeof(ifr->ifr_hwaddr.sa_data), sz));
		tprints("}");
		break;
	}
	case SIOCSIFFLAGS:
	case SIOCGIFFLAGS:
		tprints("ifr_flags=");
		printflags(iffflags, (unsigned short) ifr->ifr_flags, "IFF_???");
		break;
	case SIOCSIFMETRIC:
	case SIOCGIFMETRIC:
		tprintf("ifr_metric=%d", ifr->ifr_metric);
		break;
	case SIOCSIFMTU:
	case SIOCGIFMTU:
		tprintf("ifr_mtu=%d", ifr->ifr_mtu);
		break;
	case SIOCSIFSLAVE:
	case SIOCGIFSLAVE:
		tprints("ifr_slave=");
		print_ifname(ifr->ifr_slave);
		break;
	case SIOCSIFTXQLEN:
	case SIOCGIFTXQLEN:
		tprintf("ifr_qlen=%d", ifr->ifr_qlen);
		break;
	case SIOCSIFMAP:
	case SIOCGIFMAP:
		tprintf("ifr_map={mem_start=%#" PRI_klx ", "
			"mem_end=%#" PRI_klx ", base_addr=%#x, "
			"irq=%u, dma=%u, port=%u}",
			(kernel_ulong_t) ifr->ifr_map.mem_start,
			(kernel_ulong_t) ifr->ifr_map.mem_end,
			(unsigned) ifr->ifr_map.base_addr,
			(unsigned) ifr->ifr_map.irq,
			(unsigned) ifr->ifr_map.dma,
			(unsigned) ifr->ifr_map.port);
		break;
	}
}

DIAG_POP_IGNORE_OVERRIDE_INIT

static unsigned int
print_ifc_len(int len)
{
	const unsigned int n = (unsigned int) len / sizeof(struct_ifreq);

	if (len < 0 || n * sizeof(struct_ifreq) != (unsigned int) len)
		tprintf("%d", len);
	else
		tprintf("%u * sizeof(struct ifreq)", n);

	return n;
}

static bool
print_ifconf_ifreq(struct tcb *tcp, void *elem_buf, size_t elem_size,
		   void *dummy)
{
	struct_ifreq *ifr = elem_buf;

	tprints("{ifr_name=");
	print_ifname(ifr->ifr_name);
	PRINT_FIELD_SOCKADDR(", ", *ifr, ifr_addr);
	tprints("}");

	return true;
}

/*
 * There are two different modes of operation:
 *
 * - Get buffer size.  In this case, the callee sets ifc_buf to NULL,
 *   and the kernel returns the buffer size in ifc_len.
 * - Get actual data.  In this case, the callee specifies the buffer address
 *   in ifc_buf and its size in ifc_len.  The kernel fills the buffer with
 *   the data, and its amount is returned in ifc_len.
 *
 * Note that, technically, the whole struct ifconf is overwritten,
 * so ifc_buf could be different on exit, but current ioctl handler
 * implementation does not touch it.
 */
static int
decode_ifconf(struct tcb *const tcp, const kernel_ulong_t addr)
{
	struct_ifconf *entering_ifc = NULL;
	struct_ifconf *ifc =
		entering(tcp) ? malloc(sizeof(*ifc)) : alloca(sizeof(*ifc));

	if (exiting(tcp)) {
		entering_ifc = get_tcb_priv_data(tcp);

		if (!entering_ifc) {
			error_func_msg("where is my ifconf?");
			return 0;
		}
	}

	if (!ifc || umove(tcp, addr, ifc) < 0) {
		if (entering(tcp)) {
			free(ifc);

			tprints(", ");
			printaddr(addr);
		} else {
			/*
			 * We failed to fetch the structure on exiting syscall,
			 * print whatever was fetched on entering syscall.
			 */
			if (!entering_ifc->ifc_buf)
				print_ifc_len(entering_ifc->ifc_len);

			tprints(", ifc_buf=");
			printaddr(ptr_to_kulong(entering_ifc->ifc_buf));

			tprints("}");
		}

		return RVAL_IOCTL_DECODED;
	}

	if (entering(tcp)) {
		tprints(", {ifc_len=");
		if (ifc->ifc_buf)
			print_ifc_len(ifc->ifc_len);

		set_tcb_priv_data(tcp, ifc, free);

		return 0;
	}

	/* exiting */

	if (entering_ifc->ifc_buf && (entering_ifc->ifc_len != ifc->ifc_len))
		tprints(" => ");
	if (!entering_ifc->ifc_buf || (entering_ifc->ifc_len != ifc->ifc_len))
		print_ifc_len(ifc->ifc_len);

	tprints(", ifc_buf=");

	if (!entering_ifc->ifc_buf || syserror(tcp)) {
		printaddr(ptr_to_kulong(entering_ifc->ifc_buf));
		if (entering_ifc->ifc_buf != ifc->ifc_buf) {
			tprints(" => ");
			printaddr(ptr_to_kulong(ifc->ifc_buf));
		}
	} else {
		struct_ifreq ifr;

		print_array(tcp, ptr_to_kulong(ifc->ifc_buf),
			    ifc->ifc_len / sizeof(struct_ifreq),
			    &ifr, sizeof(ifr),
			    tfetch_mem, print_ifconf_ifreq, NULL);
	}

	tprints("}");

	return RVAL_IOCTL_DECODED;
}

MPERS_PRINTER_DECL(int, sock_ioctl,
		   struct tcb *tcp, const unsigned int code,
		   const kernel_ulong_t arg)
{
	struct_ifreq ifr;

	switch (code) {
	case SIOCGIFCONF:
		return decode_ifconf(tcp, arg);

#ifdef SIOCBRADDBR
	case SIOCBRADDBR:
	case SIOCBRDELBR:
		tprints(", ");
		printstr(tcp, arg);
		break;
#endif

#ifdef FIOSETOWN
	case FIOSETOWN:
#endif
#ifdef SIOCSPGRP
	case SIOCSPGRP:
#endif
		tprints(", ");
		printnum_int(tcp, arg, "%d");
		break;

#ifdef FIOGETOWN
	case FIOGETOWN:
#endif
#ifdef SIOCGPGRP
	case SIOCGPGRP:
#endif
#ifdef SIOCATMARK
	case SIOCATMARK:
#endif
		if (entering(tcp))
			return 0;
		tprints(", ");
		printnum_int(tcp, arg, "%d");
		break;

#ifdef SIOCBRADDIF
	case SIOCBRADDIF:
#endif
#ifdef SIOCBRDELIF
	case SIOCBRDELIF:
#endif
		/* no arguments */
		break;

	case SIOCSIFNAME:
	case SIOCSIFADDR:
	case SIOCSIFDSTADDR:
	case SIOCSIFBRDADDR:
	case SIOCSIFNETMASK:
	case SIOCSIFFLAGS:
	case SIOCSIFMETRIC:
	case SIOCSIFMTU:
	case SIOCSIFSLAVE:
	case SIOCSIFHWADDR:
	case SIOCSIFTXQLEN:
	case SIOCSIFMAP:
		tprints(", ");
		if (umove_or_printaddr(tcp, arg, &ifr))
			break;

		tprints("{ifr_name=");
		print_ifname(ifr.ifr_name);
		tprints(", ");
		if (code == SIOCSIFNAME) {
			tprints("ifr_newname=");
			print_ifname(ifr.ifr_newname);
		} else {
			print_ifreq(tcp, code, arg, &ifr);
		}
		tprints("}");
		break;

	case SIOCGIFNAME:
	case SIOCGIFINDEX:
	case SIOCGIFADDR:
	case SIOCGIFDSTADDR:
	case SIOCGIFBRDADDR:
	case SIOCGIFNETMASK:
	case SIOCGIFFLAGS:
	case SIOCGIFMETRIC:
	case SIOCGIFMTU:
	case SIOCGIFSLAVE:
	case SIOCGIFHWADDR:
	case SIOCGIFTXQLEN:
	case SIOCGIFMAP:
		if (entering(tcp)) {
			tprints(", ");
			if (umove_or_printaddr(tcp, arg, &ifr))
				break;

			if (SIOCGIFNAME == code) {
				tprintf("{ifr_index=%d", ifr.ifr_ifindex);
			} else {
				tprints("{ifr_name=");
				print_ifname(ifr.ifr_name);
			}
			return 0;
		} else {
			if (syserror(tcp)) {
				tprints("}");
				break;
			}

			tprints(", ");
			if (umove(tcp, arg, &ifr) < 0) {
				tprints("???}");
				break;
			}

			if (SIOCGIFNAME == code) {
				tprints("ifr_name=");
				print_ifname(ifr.ifr_name);
			} else {
				print_ifreq(tcp, code, arg, &ifr);
			}
			tprints("}");
			break;
		}

	default:
		return RVAL_DECODED;
	}

	return RVAL_IOCTL_DECODED;
}