1 /*
2  *  $Id: libnet_build_stp.c,v 1.9 2004/04/13 17:32:28 mike Exp $
3  *
4  *  libnet
5  *  libnet_build_stp.c - STP packet assembler
6  *
7  *  Copyright (c) 1998 - 2004 Mike D. Schiffman <mike@infonexus.com>
8  *  All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  */
32 
33 #if (HAVE_CONFIG_H)
34 #include "../include/config.h"
35 #endif
36 #if (!(_WIN32) || (__CYGWIN__))
37 #include "../include/libnet.h"
38 #else
39 #include "../include/win32/libnet.h"
40 #endif
41 
42 libnet_ptag_t
libnet_build_stp_conf(uint16_t id,uint8_t version,uint8_t bpdu_type,uint8_t flags,const uint8_t * root_id,uint32_t root_pc,const uint8_t * bridge_id,uint16_t port_id,uint16_t message_age,uint16_t max_age,uint16_t hello_time,uint16_t f_delay,const uint8_t * payload,uint32_t payload_s,libnet_t * l,libnet_ptag_t ptag)43 libnet_build_stp_conf(uint16_t id, uint8_t version, uint8_t bpdu_type,
44 uint8_t flags, const uint8_t *root_id, uint32_t root_pc, const uint8_t *bridge_id,
45 uint16_t port_id, uint16_t message_age, uint16_t max_age,
46 uint16_t hello_time, uint16_t f_delay, const uint8_t *payload,
47 uint32_t payload_s, libnet_t *l, libnet_ptag_t ptag)
48 {
49     uint32_t n, h;
50     libnet_pblock_t *p;
51 
52     /* until we get some data marshalling in place we can't use this */
53     /* struct libnet_stp_conf_hdr stp_hdr; */
54     uint8_t stp_hdr[35];
55     uint16_t value_s;
56     uint32_t value_l;
57 
58     if (l == NULL)
59     {
60         return (-1);
61     }
62 
63     n = LIBNET_STP_CONF_H + payload_s;          /* size of memory block */
64     h = 0;                                      /* no checksum */
65 
66     /*
67      *  Find the existing protocol block if a ptag is specified, or create
68      *  a new one.
69      */
70     p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_STP_CONF_H);
71     if (p == NULL)
72     {
73         return (-1);
74     }
75 
76     /* until we get some data marshalling in place we can't use this */
77     /*
78     stp_hdr.stp_id      = htons(id);
79     stp_hdr.stp_version = version;
80     stp_hdr.stp_bpdu_type = bpdu_type;
81     stp_hdr.stp_flags   = flags;
82     memcpy(&stp_hdr.stp_rootid, root_id, 8);
83     stp_hdr.stp_rootpc = htonl(root_pc);
84     memcpy(&stp_hdr.stp_bridgeid, bridge_id, 8);
85     stp_hdr.stp_portid  = htons(port_id);
86     stp_hdr.stp_mage    = htons(message_age);
87     stp_hdr.stp_maxage  = htons(max_age);
88     stp_hdr.stp_hellot  = htons(hello_time);
89     stp_hdr.stp_fdelay  = htons(f_delay);
90     */
91 
92     value_s = htons(id);
93     memcpy(stp_hdr, &value_s, 2);
94     stp_hdr[2] = version;
95     stp_hdr[3] = bpdu_type;
96     stp_hdr[4] = flags;
97     memcpy(&stp_hdr[5], root_id, 8);
98     value_l = htonl(root_pc);
99     memcpy(&stp_hdr[13], &value_l, 4);
100     memcpy(&stp_hdr[17], bridge_id, 8);
101     value_s = htons(port_id);
102     memcpy(&stp_hdr[25], &value_s, 2);
103 #if (LIBNET_BIG_ENDIAN == 1)
104     value_s = htons(message_age);
105 #else
106     value_s = message_age;
107 #endif
108     memcpy(&stp_hdr[27], &value_s, 2);
109 #if (LIBNET_BIG_ENDIAN == 1)
110     value_s = htons(max_age);
111 #else
112     value_s = max_age;
113 #endif
114     memcpy(&stp_hdr[29], &value_s, 2);
115 #if (LIBNET_BIG_ENDIAN == 1)
116     value_s = htons(hello_time);
117 #else
118     value_s = hello_time;
119 #endif
120     memcpy(&stp_hdr[31], &value_s, 2);
121 #if (LIBNET_BIG_ENDIAN == 1)
122     value_s = htons(f_delay);
123 #else
124     value_s = f_delay;
125 #endif
126     memcpy(&stp_hdr[33], &value_s, 2);
127 
128 
129     /* until we get some data marshalling in place we can't use this */
130     /*n = libnet_pblock_append(l, p, (uint8_t *)&stp_hdr, LIBNET_STP_CONF_H); */
131     n = libnet_pblock_append(l, p, stp_hdr, LIBNET_STP_CONF_H);
132     if (n == -1)
133     {
134         goto bad;
135     }
136 
137     /* boilerplate payload sanity check / append macro */
138     LIBNET_DO_PAYLOAD(l, p);
139 
140     return (ptag ? ptag : libnet_pblock_update(l, p, h,
141             LIBNET_PBLOCK_STP_CONF_H));
142 bad:
143     libnet_pblock_delete(l, p);
144     return (-1);
145 }
146 
147 
148 libnet_ptag_t
libnet_build_stp_tcn(uint16_t id,uint8_t version,uint8_t bpdu_type,const uint8_t * payload,uint32_t payload_s,libnet_t * l,libnet_ptag_t ptag)149 libnet_build_stp_tcn(uint16_t id, uint8_t version, uint8_t bpdu_type,
150 const uint8_t *payload, uint32_t payload_s, libnet_t *l, libnet_ptag_t ptag)
151 {
152     uint32_t n, h;
153     libnet_pblock_t *p;
154 
155     struct libnet_stp_tcn_hdr stp_hdr;
156 
157     if (l == NULL)
158     {
159         return (-1);
160     }
161 
162     n = LIBNET_STP_TCN_H + payload_s;           /* size of memory block */
163     h = 0;                                      /* no checksum */
164 
165     /*
166      *  Find the existing protocol block if a ptag is specified, or create
167      *  a new one.
168      */
169     p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_STP_TCN_H);
170     if (p == NULL)
171     {
172         return (-1);
173     }
174 
175     memset(&stp_hdr, 0, sizeof(stp_hdr));
176     stp_hdr.stp_id        = htons(id);
177     stp_hdr.stp_version   = version;
178     stp_hdr.stp_bpdu_type = bpdu_type;
179 
180     n = libnet_pblock_append(l, p, (uint8_t *)&stp_hdr, LIBNET_STP_TCN_H);
181     if (n == -1)
182     {
183         goto bad;
184     }
185 
186     /* boilerplate payload sanity check / append macro */
187     LIBNET_DO_PAYLOAD(l, p);
188 
189     return (ptag ? ptag : libnet_pblock_update(l, p, h,
190             LIBNET_PBLOCK_STP_TCN_H));
191 bad:
192     libnet_pblock_delete(l, p);
193     return (-1);
194 }
195 
196 /* EOF */
197