granicus.if.org Git - strace/blob - rtnl_rule.c

   1 /*
   2  * Copyright (c) 2016 Fabien Siron <fabien.siron@epita.fr>
   3  * Copyright (c) 2017 JingPiao Chen <chenjingpiao@gmail.com>
   4  * Copyright (c) 2016-2018 The strace developers.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #include "defs.h"
  31
  32 #include "netlink_route.h"
  33 #include "nlattr.h"
  34 #include "print_fields.h"
  35
  36 #include "netlink.h"
  37 #include <linux/rtnetlink.h>
  38 #ifdef HAVE_LINUX_FIB_RULES_H
  39 # include <linux/fib_rules.h>
  40 #endif
  41
  42 #include "xlat/fib_rule_actions.h"
  43 #include "xlat/fib_rule_flags.h"
  44 #include "xlat/rtnl_rule_attrs.h"
  45
  46 static bool
  47 decode_rule_addr(struct tcb *const tcp,
  48                  const kernel_ulong_t addr,
  49                  const unsigned int len,
  50                  const void *const opaque_data)
  51 {
  52         const struct rtmsg *const rtmsg = opaque_data;
  53
  54         decode_inet_addr(tcp, addr, len, rtmsg->rtm_family, NULL);
  55
  56         return true;
  57 }
  58
  59 static bool
  60 decode_fib_rule_uid_range(struct tcb *const tcp,
  61                           const kernel_ulong_t addr,
  62                           const unsigned int len,
  63                           const void *const opaque_data)
  64 {
  65 #ifdef HAVE_STRUCT_FIB_RULE_UID_RANGE
  66         struct fib_rule_uid_range range;
  67
  68         if (len < sizeof(range))
  69                 return false;
  70         else if (!umove_or_printaddr(tcp, addr, &range)) {
  71                 PRINT_FIELD_U("{", range, start);
  72                 PRINT_FIELD_U(", ", range, end);
  73                 tprints("}");
  74         }
  75
  76         return true;
  77 #else
  78         return false;
  79 #endif
  80 }
  81
  82 static bool
  83 decode_rule_port_range(struct tcb *const tcp,
  84                        const kernel_ulong_t addr,
  85                        const unsigned int len,
  86                        const void *const opaque_data)
  87 {
  88         struct /* fib_rule_port_range */ {
  89                 uint16_t start;
  90                 uint16_t end;
  91         } range;
  92
  93         if (len < sizeof(range))
  94                 return false;
  95         else if (!umove_or_printaddr(tcp, addr, &range)) {
  96                 PRINT_FIELD_U("{", range, start);
  97                 PRINT_FIELD_U(", ", range, end);
  98                 tprints("}");
  99         }
 100
 101         return true;
 102 }
 103
 104 static const nla_decoder_t fib_rule_hdr_nla_decoders[] = {
 105         [FRA_DST]                       = decode_rule_addr,
 106         [FRA_SRC]                       = decode_rule_addr,
 107         [FRA_IIFNAME]                   = decode_nla_str,
 108         [FRA_GOTO]                      = decode_nla_u32,
 109         [FRA_PRIORITY]                  = decode_nla_u32,
 110         [FRA_FWMARK]                    = decode_nla_u32,
 111         [FRA_FLOW]                      = decode_nla_u32,
 112         [FRA_TUN_ID]                    = decode_nla_be64,
 113         [FRA_SUPPRESS_IFGROUP]          = decode_nla_u32,
 114         [FRA_SUPPRESS_PREFIXLEN]        = decode_nla_u32,
 115         [FRA_TABLE]                     = decode_nla_rt_class,
 116         [FRA_FWMASK]                    = decode_nla_u32,
 117         [FRA_OIFNAME]                   = decode_nla_str,
 118         [FRA_PAD]                       = NULL,
 119         [FRA_L3MDEV]                    = decode_nla_u8,
 120         [FRA_UID_RANGE]                 = decode_fib_rule_uid_range,
 121         [FRA_PROTOCOL]                  = decode_nla_rt_proto,
 122         [FRA_IP_PROTO]                  = decode_nla_ip_proto,
 123         [FRA_SPORT_RANGE]               = decode_rule_port_range,
 124         [FRA_DPORT_RANGE]               = decode_rule_port_range,
 125 };
 126
 127 DECL_NETLINK_ROUTE_DECODER(decode_fib_rule_hdr)
 128 {
 129         /*
 130          * struct rtmsg and struct fib_rule_hdr are essentially
 131          * the same structure, use struct rtmsg but treat it as
 132          * struct fib_rule_hdr.
 133          */
 134         struct rtmsg msg = { .rtm_family = family };
 135         size_t offset = sizeof(msg.rtm_family);
 136         bool decode_nla = false;
 137
 138         tprints("{family=");
 139         printxval(addrfams, msg.rtm_family, "AF_???");
 140
 141         tprints(", ");
 142         if (len >= sizeof(msg)) {
 143                 if (!umoven_or_printaddr(tcp, addr + offset,
 144                                          sizeof(msg) - offset,
 145                                          (char *) &msg + offset)) {
 146                         tprintf("dst_len=%u, src_len=%u",
 147                                 msg.rtm_dst_len, msg.rtm_src_len);
 148                         tprints(", tos=");
 149                         printflags(ip_type_of_services, msg.rtm_tos,
 150                                    "IPTOS_TOS_???");
 151                         tprints(", table=");
 152                         printxval(routing_table_ids, msg.rtm_table, NULL);
 153                         tprints(", action=");
 154                         printxval(fib_rule_actions, msg.rtm_type, "FR_ACT_???");
 155                         tprints(", flags=");
 156                         printflags(fib_rule_flags, msg.rtm_flags,
 157                                    "FIB_RULE_???");
 158                         decode_nla = true;
 159                 }
 160         } else
 161                 tprints("...");
 162         tprints("}");
 163
 164         offset = NLMSG_ALIGN(sizeof(msg));
 165         if (decode_nla && len > offset) {
 166                 tprints(", ");
 167                 decode_nlattr(tcp, addr + offset, len - offset,
 168                               rtnl_rule_attrs, "FRA_???",
 169                               fib_rule_hdr_nla_decoders,
 170                               ARRAY_SIZE(fib_rule_hdr_nla_decoders), &msg);
 171         }
 172 }