2 * wire2host.h - from wire conversion routines
4 * a Net::DNS like library for C
6 * (c) NLnet Labs, 2005-2006
8 * See the file LICENSE for the license
14 * Contains functions that translate dns data from the wire format (as sent
15 * by servers and clients) to the internal structures.
18 #ifndef LDNS_WIRE2HOST_H
19 #define LDNS_WIRE2HOST_H
21 #include <ldns/rdata.h>
22 #include <ldns/common.h>
23 #include <ldns/error.h>
25 #include <ldns/packet.h>
27 /* The length of the header */
28 #define LDNS_HEADER_SIZE 12
30 /* First octet of flags */
31 #define LDNS_RD_MASK 0x01U
32 #define LDNS_RD_SHIFT 0
33 #define LDNS_RD_WIRE(wirebuf) (*(wirebuf+2) & LDNS_RD_MASK)
34 #define LDNS_RD_SET(wirebuf) (*(wirebuf+2) |= LDNS_RD_MASK)
35 #define LDNS_RD_CLR(wirebuf) (*(wirebuf+2) &= ~LDNS_RD_MASK)
37 #define LDNS_TC_MASK 0x02U
38 #define LDNS_TC_SHIFT 1
39 #define LDNS_TC_WIRE(wirebuf) (*(wirebuf+2) & LDNS_TC_MASK)
40 #define LDNS_TC_SET(wirebuf) (*(wirebuf+2) |= LDNS_TC_MASK)
41 #define LDNS_TC_CLR(wirebuf) (*(wirebuf+2) &= ~LDNS_TC_MASK)
43 #define LDNS_AA_MASK 0x04U
44 #define LDNS_AA_SHIFT 2
45 #define LDNS_AA_WIRE(wirebuf) (*(wirebuf+2) & LDNS_AA_MASK)
46 #define LDNS_AA_SET(wirebuf) (*(wirebuf+2) |= LDNS_AA_MASK)
47 #define LDNS_AA_CLR(wirebuf) (*(wirebuf+2) &= ~LDNS_AA_MASK)
49 #define LDNS_OPCODE_MASK 0x78U
50 #define LDNS_OPCODE_SHIFT 3
51 #define LDNS_OPCODE_WIRE(wirebuf) ((*(wirebuf+2) & LDNS_OPCODE_MASK) >> LDNS_OPCODE_SHIFT)
52 #define LDNS_OPCODE_SET(wirebuf, opcode) \
53 (*(wirebuf+2) = ((*(wirebuf+2)) & ~LDNS_OPCODE_MASK) | ((opcode) << LDNS_OPCODE_SHIFT))
55 #define LDNS_QR_MASK 0x80U
56 #define LDNS_QR_SHIFT 7
57 #define LDNS_QR_WIRE(wirebuf) (*(wirebuf+2) & LDNS_QR_MASK)
58 #define LDNS_QR_SET(wirebuf) (*(wirebuf+2) |= LDNS_QR_MASK)
59 #define LDNS_QR_CLR(wirebuf) (*(wirebuf+2) &= ~LDNS_QR_MASK)
61 /* Second octet of flags */
62 #define LDNS_RCODE_MASK 0x0fU
63 #define LDNS_RCODE_SHIFT 0
64 #define LDNS_RCODE_WIRE(wirebuf) (*(wirebuf+3) & LDNS_RCODE_MASK)
65 #define LDNS_RCODE_SET(wirebuf, rcode) \
66 (*(wirebuf+3) = ((*(wirebuf+3)) & ~LDNS_RCODE_MASK) | (rcode))
68 #define LDNS_CD_MASK 0x10U
69 #define LDNS_CD_SHIFT 4
70 #define LDNS_CD_WIRE(wirebuf) (*(wirebuf+3) & LDNS_CD_MASK)
71 #define LDNS_CD_SET(wirebuf) (*(wirebuf+3) |= LDNS_CD_MASK)
72 #define LDNS_CD_CLR(wirebuf) (*(wirebuf+3) &= ~LDNS_CD_MASK)
74 #define LDNS_AD_MASK 0x20U
75 #define LDNS_AD_SHIFT 5
76 #define LDNS_AD_WIRE(wirebuf) (*(wirebuf+3) & LDNS_AD_MASK)
77 #define LDNS_AD_SET(wirebuf) (*(wirebuf+3) |= LDNS_AD_MASK)
78 #define LDNS_AD_CLR(wirebuf) (*(wirebuf+3) &= ~LDNS_AD_MASK)
80 #define LDNS_Z_MASK 0x40U
81 #define LDNS_Z_SHIFT 6
82 #define LDNS_Z_WIRE(wirebuf) (*(wirebuf+3) & LDNS_Z_MASK)
83 #define LDNS_Z_SET(wirebuf) (*(wirebuf+3) |= LDNS_Z_MASK)
84 #define LDNS_Z_CLR(wirebuf) (*(wirebuf+3) &= ~LDNS_Z_MASK)
86 #define LDNS_RA_MASK 0x80U
87 #define LDNS_RA_SHIFT 7
88 #define LDNS_RA_WIRE(wirebuf) (*(wirebuf+3) & LDNS_RA_MASK)
89 #define LDNS_RA_SET(wirebuf) (*(wirebuf+3) |= LDNS_RA_MASK)
90 #define LDNS_RA_CLR(wirebuf) (*(wirebuf+3) &= ~LDNS_RA_MASK)
93 #define LDNS_ID_WIRE(wirebuf) (ldns_read_uint16(wirebuf))
94 #define LDNS_ID_SET(wirebuf, id) (ldns_write_uint16(wirebuf, id))
96 /* Counter of the question section */
97 #define LDNS_QDCOUNT_OFF 4
99 #define QDCOUNT(wirebuf) (ntohs(*(uint16_t *)(wirebuf+QDCOUNT_OFF)))
101 #define LDNS_QDCOUNT(wirebuf) (ldns_read_uint16(wirebuf+LDNS_QDCOUNT_OFF))
103 /* Counter of the answer section */
104 #define LDNS_ANCOUNT_OFF 6
105 #define LDNS_ANCOUNT(wirebuf) (ldns_read_uint16(wirebuf+LDNS_ANCOUNT_OFF))
107 /* Counter of the authority section */
108 #define LDNS_NSCOUNT_OFF 8
109 #define LDNS_NSCOUNT(wirebuf) (ldns_read_uint16(wirebuf+LDNS_NSCOUNT_OFF))
111 /* Counter of the additional section */
112 #define LDNS_ARCOUNT_OFF 10
113 #define LDNS_ARCOUNT(wirebuf) (ldns_read_uint16(wirebuf+LDNS_ARCOUNT_OFF))
116 * converts the data on the uint8_t bytearray (in wire format) to a DNS packet.
117 * This function will initialize and allocate memory space for the packet
120 * \param[in] packet pointer to the structure to hold the packet
121 * \param[in] data pointer to the buffer with the data
122 * \param[in] len the length of the data buffer (in bytes)
123 * \return LDNS_STATUS_OK if everything succeeds, error otherwise
125 ldns_status ldns_wire2pkt(ldns_pkt **packet, const uint8_t *data, size_t len);
128 * converts the data on the uint8_t bytearray (in wire format) to a DNS packet.
129 * This function will initialize and allocate memory space for the packet
132 * \param[in] packet pointer to the structure to hold the packet
133 * \param[in] buffer the buffer with the data
134 * \return LDNS_STATUS_OK if everything succeeds, error otherwise
136 ldns_status ldns_buffer2pkt_wire(ldns_pkt **packet, ldns_buffer *buffer);
139 * converts the data on the uint8_t bytearray (in wire format) to a DNS
140 * dname rdata field. This function will initialize and allocate memory
141 * space for the dname structure. The length of the wiredata of this rdf
142 * is added to the *pos value.
144 * \param[in] dname pointer to the structure to hold the rdata value
145 * \param[in] wire pointer to the buffer with the data
146 * \param[in] max the length of the data buffer (in bytes)
147 * \param[in] pos the position of the rdf in the buffer (ie. the number of bytes
148 * from the start of the buffer)
149 * \return LDNS_STATUS_OK if everything succeeds, error otherwise
151 ldns_status ldns_wire2dname(ldns_rdf **dname, const uint8_t *wire, size_t max, size_t *pos);
154 * converts the data on the uint8_t bytearray (in wire format) to DNS
155 * rdata fields, and adds them to the list of rdfs of the given rr.
156 * This function will initialize and allocate memory space for the dname
158 * The length of the wiredata of these rdfs is added to the *pos value.
160 * All rdfs belonging to the RR are read; the rr should have no rdfs
161 * yet. An error is returned if the format cannot be parsed.
163 * \param[in] rr pointer to the ldns_rr structure to hold the rdata value
164 * \param[in] wire pointer to the buffer with the data
165 * \param[in] max the length of the data buffer (in bytes)
166 * \param[in] pos the position of the rdf in the buffer (ie. the number of bytes
167 * from the start of the buffer)
168 * \return LDNS_STATUS_OK if everything succeeds, error otherwise
170 ldns_status ldns_wire2rdf(ldns_rr *rr, const uint8_t *wire, size_t max, size_t *pos);
173 * converts the data on the uint8_t bytearray (in wire format) to a DNS
175 * This function will initialize and allocate memory space for the rr
177 * The length of the wiredata of this rr is added to the *pos value.
179 * \param[in] rr pointer to the structure to hold the rdata value
180 * \param[in] wire pointer to the buffer with the data
181 * \param[in] max the length of the data buffer (in bytes)
182 * \param[in] pos the position of the rr in the buffer (ie. the number of bytes
183 * from the start of the buffer)
184 * \param[in] section the section in the packet the rr is meant for
185 * \return LDNS_STATUS_OK if everything succeeds, error otherwise
187 ldns_status ldns_wire2rr(ldns_rr **rr, const uint8_t *wire, size_t max, size_t *pos, ldns_pkt_section section);
189 #endif /* LDNS_WIRE2HOST_H */