1 /*
2  * include/irc_reslib.h
3  *
4  * $Id: reslib.h 26094 2008-09-19 15:33:46Z androsyn $
5  */
6 
7 #ifndef _CHARYBDIS_RESLIB_H
8 #define _CHARYBDIS_RESLIB_H
9 
10 /* Here we define some values lifted from nameser.h */
11 #define NS_NOTIFY_OP 4
12 #define NS_INT16SZ 2
13 #define NS_IN6ADDRSZ    16
14 #define NS_INADDRSZ      4
15 #define NS_INT32SZ 4
16 #define NS_CMPRSFLGS    0xc0
17 #define NS_MAXCDNAME 255
18 #define QUERY 0
19 #define IQUERY 1
20 #define NO_ERRORS 0
21 #define SERVFAIL 2
22 #define NXDOMAIN 3
23 #define T_A 1
24 #define T_AAAA 28
25 #define T_PTR 12
26 #define T_CNAME 5
27 #define T_NULL 10
28 #define C_IN 1
29 #define QFIXEDSZ 4
30 #define RRFIXEDSZ 10
31 #define HFIXEDSZ 12
32 
33 typedef struct
34 {
35 	unsigned id:16;		/* query identification number */
36 #ifdef WORDS_BIGENDIAN
37 	/* fields in third byte */
38 	unsigned qr:1;		/* response flag */
39 	unsigned opcode:4;	/* purpose of message */
40 	unsigned aa:1;		/* authoritive answer */
41 	unsigned tc:1;		/* truncated message */
42 	unsigned rd:1;		/* recursion desired */
43 	/* fields in fourth byte */
44 	unsigned ra:1;		/* recursion available */
45 	unsigned unused:1;	/* unused bits (MBZ as of 4.9.3a3) */
46 	unsigned ad:1;		/* authentic data from named */
47 	unsigned cd:1;		/* checking disabled by resolver */
48 	unsigned rcode:4;	/* response code */
49 #else
50 	/* fields in third byte */
51 	unsigned rd:1;		/* recursion desired */
52 	unsigned tc:1;		/* truncated message */
53 	unsigned aa:1;		/* authoritive answer */
54 	unsigned opcode:4;	/* purpose of message */
55 	unsigned qr:1;		/* response flag */
56 	/* fields in fourth byte */
57 	unsigned rcode:4;	/* response code */
58 	unsigned cd:1;		/* checking disabled by resolver */
59 	unsigned ad:1;		/* authentic data from named */
60 	unsigned unused:1;	/* unused bits (MBZ as of 4.9.3a3) */
61 	unsigned ra:1;		/* recursion available */
62 #endif
63 	/* remaining bytes */
64 	unsigned qdcount:16;	/* number of question entries */
65 	unsigned ancount:16;	/* number of answer entries */
66 	unsigned nscount:16;	/* number of authority entries */
67 	unsigned arcount:16;	/* number of resource entries */
68 } HEADER;
69 
70 /*
71  * Inline versions of get/put short/long.  Pointer is advanced.
72  */
73 #define IRC_NS_GET16(s, cp) { \
74 	const unsigned char *t_cp = (const unsigned char *)(cp); \
75 	(s) = ((uint16_t)t_cp[0] << 8) \
76 	    | ((uint16_t)t_cp[1]) \
77 	    ; \
78 	(cp) += NS_INT16SZ; \
79 }
80 
81 #define IRC_NS_GET32(l, cp) { \
82 	const unsigned char *t_cp = (const unsigned char *)(cp); \
83 	(l) = ((uint32_t)t_cp[0] << 24) \
84 	    | ((uint32_t)t_cp[1] << 16) \
85 	    | ((uint32_t)t_cp[2] << 8) \
86 	    | ((uint32_t)t_cp[3]) \
87 	    ; \
88 	(cp) += NS_INT32SZ; \
89 }
90 
91 #define IRC_NS_PUT16(s, cp) { \
92 	uint16_t t_s = (uint16_t)(s); \
93 	unsigned char *t_cp = (unsigned char *)(cp); \
94 	*t_cp++ = t_s >> 8; \
95 	*t_cp   = t_s; \
96 	(cp) += NS_INT16SZ; \
97 }
98 
99 #define IRC_NS_PUT32(l, cp) { \
100 	uint32_t t_l = (uint32_t)(l); \
101 	unsigned char *t_cp = (unsigned char *)(cp); \
102 	*t_cp++ = t_l >> 24; \
103 	*t_cp++ = t_l >> 16; \
104 	*t_cp++ = t_l >> 8; \
105 	*t_cp   = t_l; \
106 	(cp) += NS_INT32SZ; \
107 }
108 
109 extern int irc_res_init(void);
110 extern int irc_dn_expand(const unsigned char *msg, const unsigned char *eom,
111 			 const unsigned char *src, char *dst, int dstsiz);
112 extern int irc_dn_skipname(const unsigned char *ptr, const unsigned char *eom);
113 extern unsigned int irc_ns_get16(const unsigned char *src);
114 extern unsigned long irc_ns_get32(const unsigned char *src);
115 extern void irc_ns_put16(unsigned int src, unsigned char *dst);
116 extern void irc_ns_put32(unsigned long src, unsigned char *dst);
117 extern int irc_res_mkquery(const char *dname, int class, int type, void *buf, int buflen);
118 
119 #endif
120