1 /*
2  * Copyright (c) 2007 - Andrey "nording" Chernyak <andrew@nording.ru>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that: (1) source code distributions
6  * retain the above copyright notice and this paragraph in its entirety, (2)
7  * distributions including binary code include the above copyright notice and
8  * this paragraph in its entirety in the documentation or other materials
9  * provided with the distribution, and (3) all advertising materials mentioning
10  * features or use of this software display the following acknowledgement:
11  * ``This product includes software developed by the University of California,
12  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
13  * the University nor the names of its contributors may be used to endorse
14  * or promote products derived from this software without specific prior
15  * written permission.
16  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
17  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19  *
20  * Format and print Realtek Remote Control Protocol (RRCP)
21  * and Realtek Echo Protocol (RRCP-REP) packets.
22  */
23 
24 #define NETDISSECT_REWORKED
25 #ifdef HAVE_CONFIG_H
26 #include "config.h"
27 #endif
28 
29 #include <tcpdump-stdinc.h>
30 
31 #include "interface.h"
32 #include "addrtoname.h"
33 #include "extract.h"
34 #include "ether.h"
35 
36 #define RRCP_OPCODE_MASK	0x7F	/* 0x00 = hello, 0x01 = get, 0x02 = set */
37 #define RRCP_ISREPLY		0x80	/* 0 = request to switch, 0x80 = reply from switch */
38 
39 #define RRCP_PROTO_OFFSET		0	/* proto - 1 byte, must be 1 */
40 #define RRCP_OPCODE_ISREPLY_OFFSET	1	/* opcode and isreply flag - 1 byte */
41 #define RRCP_AUTHKEY_OFFSET		2	/* authorization key - 2 bytes, 0x2379 by default */
42 
43 /* most packets */
44 #define RRCP_REG_ADDR_OFFSET		4	/* register address - 2 bytes */
45 #define RRCP_REG_DATA_OFFSET		6	/* register data - 4 bytes */
46 #define RRCP_COOKIE1_OFFSET		10	/* 4 bytes */
47 #define RRCP_COOKIE2_OFFSET		14	/* 4 bytes */
48 
49 /* hello reply packets */
50 #define RRCP_DOWNLINK_PORT_OFFSET	4	/* 1 byte */
51 #define RRCP_UPLINK_PORT_OFFSET		5	/* 1 byte */
52 #define RRCP_UPLINK_MAC_OFFSET		6	/* 6 byte MAC address */
53 #define RRCP_CHIP_ID_OFFSET		12	/* 2 bytes */
54 #define RRCP_VENDOR_ID_OFFSET		14	/* 4 bytes */
55 
56 static const struct tok proto_values[] = {
57 	{ 1, "RRCP" },
58 	{ 2, "RRCP-REP" },
59 	{ 0, NULL }
60 };
61 
62 static const struct tok opcode_values[] = {
63 	{ 0, "hello" },
64 	{ 1, "get" },
65 	{ 2, "set" },
66 	{ 0, NULL }
67 };
68 
69 /*
70  * Print RRCP requests
71  */
72 void
rrcp_print(netdissect_options * ndo,register const u_char * cp,u_int length _U_)73 rrcp_print(netdissect_options *ndo,
74 	  register const u_char *cp,
75 	  u_int length _U_)
76 {
77 	const u_char *rrcp;
78 	uint8_t rrcp_proto;
79 	uint8_t rrcp_opcode;
80 	register const struct ether_header *ep;
81 	char proto_str[16];
82 	char opcode_str[32];
83 
84 	ep = (const struct ether_header *)cp;
85 	rrcp = cp + ETHER_HDRLEN;
86 
87 	ND_TCHECK(*(rrcp + RRCP_PROTO_OFFSET));
88 	rrcp_proto = *(rrcp + RRCP_PROTO_OFFSET);
89 	ND_TCHECK(*(rrcp + RRCP_OPCODE_ISREPLY_OFFSET));
90 	rrcp_opcode = (*(rrcp + RRCP_OPCODE_ISREPLY_OFFSET)) & RRCP_OPCODE_MASK;
91         ND_PRINT((ndo, "%s > %s, %s %s",
92 		etheraddr_string(ndo, ESRC(ep)),
93 		etheraddr_string(ndo, EDST(ep)),
94 		tok2strbuf(proto_values,"RRCP-0x%02x",rrcp_proto,proto_str,sizeof(proto_str)),
95 		((*(rrcp + RRCP_OPCODE_ISREPLY_OFFSET)) & RRCP_ISREPLY) ? "reply" : "query"));
96 	if (rrcp_proto==1){
97     	    ND_PRINT((ndo, ": %s",
98 		     tok2strbuf(opcode_values,"unknown opcode (0x%02x)",rrcp_opcode,opcode_str,sizeof(opcode_str))));
99 	}
100 	if (rrcp_opcode==1 || rrcp_opcode==2){
101 	    ND_TCHECK2(*(rrcp + RRCP_REG_ADDR_OFFSET), 6);
102     	    ND_PRINT((ndo, " addr=0x%04x, data=0x%08x",
103                      EXTRACT_LE_16BITS(rrcp + RRCP_REG_ADDR_OFFSET),
104                      EXTRACT_LE_32BITS(rrcp + RRCP_REG_DATA_OFFSET)));
105 	}
106 	if (rrcp_proto==1){
107 	    ND_TCHECK2(*(rrcp + RRCP_AUTHKEY_OFFSET), 2);
108     	    ND_PRINT((ndo, ", auth=0x%04x",
109 		  EXTRACT_16BITS(rrcp + RRCP_AUTHKEY_OFFSET)));
110 	}
111 	if (rrcp_proto==1 && rrcp_opcode==0 &&
112 	     ((*(rrcp + RRCP_OPCODE_ISREPLY_OFFSET)) & RRCP_ISREPLY)){
113 	    ND_TCHECK2(*(rrcp + RRCP_VENDOR_ID_OFFSET), 4);
114 	    ND_PRINT((ndo, " downlink_port=%d, uplink_port=%d, uplink_mac=%s, vendor_id=%08x ,chip_id=%04x ",
115 		     *(rrcp + RRCP_DOWNLINK_PORT_OFFSET),
116 		     *(rrcp + RRCP_UPLINK_PORT_OFFSET),
117 		     etheraddr_string(ndo, rrcp + RRCP_UPLINK_MAC_OFFSET),
118 		     EXTRACT_32BITS(rrcp + RRCP_VENDOR_ID_OFFSET),
119 		     EXTRACT_16BITS(rrcp + RRCP_CHIP_ID_OFFSET)));
120 	}else if (rrcp_opcode==1 || rrcp_opcode==2 || rrcp_proto==2){
121 	    ND_TCHECK2(*(rrcp + RRCP_COOKIE2_OFFSET), 4);
122 	    ND_PRINT((ndo, ", cookie=0x%08x%08x ",
123 		    EXTRACT_32BITS(rrcp + RRCP_COOKIE2_OFFSET),
124 		    EXTRACT_32BITS(rrcp + RRCP_COOKIE1_OFFSET)));
125 	}
126 	return;
127 
128 trunc:
129 	ND_PRINT((ndo, "[|rrcp]"));
130 }
131