2 * @brief IRC resolver API.
3 * @version $Id: res.h 1823 2007-08-09 03:41:18Z entrope $
9 #ifndef INCLUDED_config_h
13 #ifndef INCLUDED_sys_types_h
14 #include <sys/types.h>
15 #define INCLUDED_sys_types_h
18 #ifndef INCLUDED_sys_socket_h
19 #include <sys/socket.h>
20 #define INCLUDED_sys_socket_h
25 #ifndef INCLUDED_netinet_in_h
26 #include <netinet/in.h>
27 #define INCLUDED_netinet_in_h
31 #ifndef INCLUDED_stdint_h
33 #define INCLUDED_stdint_h
40 /* Here we define some values lifted from nameser.h */
41 #define NS_INT16SZ 2 /**< Size of a 16-bit value. */
42 #define NS_INT32SZ 4 /**< Size of a 32-bit value. */
43 #define NS_CMPRSFLGS 0xc0 /**< Prefix flags that indicate special types */
44 #define NS_MAXCDNAME 255 /**< Maximum length of a compressed domain name. */
45 #define QUERY 0 /**< Forward (normal) DNS query operation. */
46 #define NO_ERRORS 0 /**< No errors processing a query. */
47 #define SERVFAIL 2 /**< Server error while processing a query. */
48 #define NXDOMAIN 3 /**< Domain name in query does not exist. */
49 #define T_A 1 /**< Hostname -> IPv4 query type. */
50 #define T_AAAA 28 /**< Hostname -> IPv6 query type. */
51 #define T_PTR 12 /**< IP(v4 or v6) -> hostname query type. */
52 #define T_CNAME 5 /**< Canonical name resolution query type. */
53 #define C_IN 1 /**< Internet query class. */
54 #define QFIXEDSZ 4 /**< Length of fixed-size part of query. */
55 #define HFIXEDSZ 12 /**< Length of fixed-size DNS header. */
57 /** Structure to store an IP address. */
60 unsigned short in6_16[8]; /**< IPv6 encoded parts, little-endian. */
63 /** Structure to store an IP address and port number. */
66 struct irc_in_addr addr; /**< IP address. */
67 unsigned short port; /**< Port number, host-endian. */
70 /** DNS callback function signature. */
71 typedef void (*dns_callback_f)(void *vptr, const struct irc_in_addr *addr, const char *h_name);
73 /** DNS query and response header. */
76 unsigned id :16; /**< query identification number */
77 #ifdef WORDS_BIGENDIAN
78 /* fields in third byte */
79 unsigned qr: 1; /**< response flag */
80 unsigned opcode: 4; /**< purpose of message */
81 unsigned aa: 1; /**< authoritive answer */
82 unsigned tc: 1; /**< truncated message */
83 unsigned rd: 1; /**< recursion desired */
84 /* fields in fourth byte */
85 unsigned ra: 1; /**< recursion available */
86 unsigned unused :1; /**< unused bits (MBZ as of 4.9.3a3) */
87 unsigned ad: 1; /**< authentic data from named */
88 unsigned cd: 1; /**< checking disabled by resolver */
89 unsigned rcode :4; /**< response code */
91 /* fields in third byte */
92 unsigned rd :1; /**< recursion desired */
93 unsigned tc :1; /**< truncated message */
94 unsigned aa :1; /**< authoritive answer */
95 unsigned opcode :4; /**< purpose of message */
96 unsigned qr :1; /**< response flag */
97 /* fields in fourth byte */
98 unsigned rcode :4; /**< response code */
99 unsigned cd: 1; /**< checking disabled by resolver */
100 unsigned ad: 1; /**< authentic data from named */
101 unsigned unused :1; /**< unused bits (MBZ as of 4.9.3a3) */
102 unsigned ra :1; /**< recursion available */
104 /* remaining bytes */
105 unsigned qdcount :16; /**< number of question entries */
106 unsigned ancount :16; /**< number of answer entries */
107 unsigned nscount :16; /**< number of authority entries */
108 unsigned arcount :16; /**< number of resource entries */
111 extern void restart_resolver(void);
112 extern void clear_nameservers(void);
113 extern void add_nameserver(const char *ipaddr);
114 extern void add_local_domain(char *hname, size_t size);
115 extern size_t cres_mem(struct Client* cptr);
116 extern void delete_resolver_queries(const void *vptr);
117 extern void report_dns_servers(struct Client *source_p, const struct StatDesc *sd, char *param);
118 extern void gethost_byname(const char *name, dns_callback_f callback, void *ctx);
119 extern void gethost_byaddr(const struct irc_in_addr *addr, dns_callback_f callback, void *ctx);
121 /** Evaluate to non-zero if \a ADDR is an unspecified (all zeros) address. */
122 #define irc_in_addr_unspec(ADDR) (((ADDR)->in6_16[0] == 0) \
123 && ((ADDR)->in6_16[1] == 0) \
124 && ((ADDR)->in6_16[2] == 0) \
125 && ((ADDR)->in6_16[3] == 0) \
126 && ((ADDR)->in6_16[4] == 0) \
127 && ((ADDR)->in6_16[6] == 0) \
128 && ((ADDR)->in6_16[7] == 0) \
129 && ((ADDR)->in6_16[5] == 0 \
130 || (ADDR)->in6_16[5] == 65535))
131 /** Evaluate to non-zero if \a ADDR is a valid address (not all 0s and not all 1s). */
132 #define irc_in_addr_valid(ADDR) (((ADDR)->in6_16[0] && ~(ADDR)->in6_16[0]) \
133 || (ADDR)->in6_16[1] != (ADDR)->in6_16[0] \
134 || (ADDR)->in6_16[2] != (ADDR)->in6_16[0] \
135 || (ADDR)->in6_16[3] != (ADDR)->in6_16[0] \
136 || (ADDR)->in6_16[4] != (ADDR)->in6_16[0] \
137 || (ADDR)->in6_16[5] != (ADDR)->in6_16[0] \
138 || (ADDR)->in6_16[6] != (ADDR)->in6_16[0] \
139 || (ADDR)->in6_16[7] != (ADDR)->in6_16[0])
140 /** Evaluate to non-zero if \a ADDR (of type struct irc_in_addr) is an IPv4 address. */
141 #define irc_in_addr_is_ipv4(ADDR) (!(ADDR)->in6_16[0] && !(ADDR)->in6_16[1] && !(ADDR)->in6_16[2] \
142 && !(ADDR)->in6_16[3] && !(ADDR)->in6_16[4] \
143 && ((!(ADDR)->in6_16[5] && (ADDR)->in6_16[6]) \
144 || (ADDR)->in6_16[5] == 65535))
145 /** Evaluate to non-zero if \a A is a different IP than \a B. */
146 #define irc_in_addr_cmp(A,B) (irc_in_addr_is_ipv4(A) ? ((A)->in6_16[6] != (B)->in6_16[6] \
147 || (A)->in6_16[7] != (B)->in6_16[7] || !irc_in_addr_is_ipv4(B)) \
148 : memcmp((A), (B), sizeof(struct irc_in_addr)))
149 /** Evaluate to non-zero if \a ADDR is a loopback address. */
150 #define irc_in_addr_is_loopback(ADDR) (!(ADDR)->in6_16[0] && !(ADDR)->in6_16[1] && !(ADDR)->in6_16[2] \
151 && !(ADDR)->in6_16[3] && !(ADDR)->in6_16[4] \
152 && ((!(ADDR)->in6_16[5] \
153 && ((!(ADDR)->in6_16[6] && (ADDR)->in6_16[7] == htons(1)) \
154 || (ntohs((ADDR)->in6_16[6]) & 0xff00) == 0x7f00)) \
155 || (((ADDR)->in6_16[5] == 65535) \
156 && (ntohs((ADDR)->in6_16[6]) & 0xff00) == 0x7f00)))