1 /* 2 * net.h 3 * 4 * DNS Resolver definitions 5 * 6 * a Net::DNS like library for C 7 * 8 * (c) NLnet Labs, 2005-2006 9 * 10 * See the file LICENSE for the license 11 */ 12 13 #ifndef LDNS_NET_H 14 #define LDNS_NET_H 15 16 #include <ldns/ldns.h> 17 #include <sys/socket.h> 18 19 #ifdef __cplusplus 20 extern "C" { 21 #endif 22 23 #define LDNS_DEFAULT_TIMEOUT_SEC 5 24 #define LDNS_DEFAULT_TIMEOUT_USEC 0 25 26 /** 27 * \file 28 * 29 * Contains functions to send and receive packets over a network. 30 */ 31 32 /** 33 * Sends a buffer to an ip using udp and return the respons as a ldns_pkt 34 * \param[in] qbin the ldns_buffer to be send 35 * \param[in] to the ip addr to send to 36 * \param[in] tolen length of the ip addr 37 * \param[in] timeout the timeout value for the network 38 * \param[out] answersize size of the packet 39 * \param[out] result packet with the answer 40 * \return status 41 */ 42 ldns_status ldns_udp_send(uint8_t **result, ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout, size_t *answersize); 43 44 /** 45 * Send an udp query and don't wait for an answer but return 46 * the socket 47 * \param[in] qbin the ldns_buffer to be send 48 * \param[in] to the ip addr to send to 49 * \param[in] tolen length of the ip addr 50 * \param[in] timeout *unused*, was the timeout value for the network 51 * \return the socket used 52 */ 53 int ldns_udp_bgsend(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 54 55 /** 56 * Send an tcp query and don't wait for an answer but return 57 * the socket 58 * \param[in] qbin the ldns_buffer to be send 59 * \param[in] to the ip addr to send to 60 * \param[in] tolen length of the ip addr 61 * \param[in] timeout the timeout value for the connect attempt 62 * \return the socket used 63 */ 64 int ldns_tcp_bgsend(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 65 66 /** 67 * Sends a buffer to an ip using tcp and return the respons as a ldns_pkt 68 * \param[in] qbin the ldns_buffer to be send 69 * \param[in] qbin the ldns_buffer to be send 70 * \param[in] to the ip addr to send to 71 * \param[in] tolen length of the ip addr 72 * \param[in] timeout the timeout value for the network 73 * \param[out] answersize size of the packet 74 * \param[out] result packet with the answer 75 * \return status 76 */ 77 ldns_status ldns_tcp_send(uint8_t **result, ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout, size_t *answersize); 78 79 /** 80 * Sends ptk to the nameserver at the resolver object. Returns the data 81 * as a ldns_pkt 82 * 83 * \param[out] pkt packet received from the nameserver 84 * \param[in] r the resolver to use 85 * \param[in] query_pkt the query to send 86 * \return status 87 */ 88 ldns_status ldns_send(ldns_pkt **pkt, ldns_resolver *r, const ldns_pkt *query_pkt); 89 90 /** 91 * Sends and ldns_buffer (presumably containing a packet to the nameserver at the resolver object. Returns the data 92 * as a ldns_pkt 93 * 94 * \param[out] pkt packet received from the nameserver 95 * \param[in] r the resolver to use 96 * \param[in] qb the buffer to send 97 * \param[in] tsig_mac the tsig MAC to authenticate the response with (NULL to do no TSIG authentication) 98 * \return status 99 */ 100 ldns_status ldns_send_buffer(ldns_pkt **pkt, ldns_resolver *r, ldns_buffer *qb, ldns_rdf *tsig_mac); 101 102 /** 103 * Create a tcp socket to the specified address 104 * \param[in] to ip and family 105 * \param[in] tolen length of to 106 * \param[in] timeout timeout for the connect attempt 107 * \return a socket descriptor 108 */ 109 int ldns_tcp_connect(const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 110 111 /** 112 * Create a udp socket to the specified address 113 * \param[in] to ip and family 114 * \param[in] timeout *unused*, was timeout for the socket 115 * \return a socket descriptor 116 */ 117 int ldns_udp_connect(const struct sockaddr_storage *to, struct timeval timeout); 118 119 /** 120 * send a query via tcp to a server. Don't want for the answer 121 * 122 * \param[in] qbin the buffer to send 123 * \param[in] sockfd the socket to use 124 * \param[in] to which ip to send it 125 * \param[in] tolen socketlen 126 * \return number of bytes sent 127 */ 128 ssize_t ldns_tcp_send_query(ldns_buffer *qbin, int sockfd, const struct sockaddr_storage *to, socklen_t tolen); 129 130 /** 131 * send a query via udp to a server. Don;t want for the answer 132 * 133 * \param[in] qbin the buffer to send 134 * \param[in] sockfd the socket to use 135 * \param[in] to which ip to send it 136 * \param[in] tolen socketlen 137 * \return number of bytes sent 138 */ 139 ssize_t ldns_udp_send_query(ldns_buffer *qbin, int sockfd, const struct sockaddr_storage *to, socklen_t tolen); 140 141 /** 142 * Gives back a raw packet from the wire and reads the header data from the given 143 * socket. Allocates the data (of size size) itself, so don't forget to free 144 * 145 * \param[in] sockfd the socket to read from 146 * \param[out] size the number of bytes that are read 147 * \param[in] timeout the time allowed between packets. 148 * \return the data read 149 */ 150 uint8_t *ldns_tcp_read_wire_timeout(int sockfd, size_t *size, struct timeval timeout); 151 152 /** 153 * This routine may block. Use ldns_tcp_read_wire_timeout, it checks timeouts. 154 * Gives back a raw packet from the wire and reads the header data from the given 155 * socket. Allocates the data (of size size) itself, so don't forget to free 156 * 157 * \param[in] sockfd the socket to read from 158 * \param[out] size the number of bytes that are read 159 * \return the data read 160 */ 161 uint8_t *ldns_tcp_read_wire(int sockfd, size_t *size); 162 163 /** 164 * Gives back a raw packet from the wire and reads the header data from the given 165 * socket. Allocates the data (of size size) itself, so don't forget to free 166 * 167 * \param[in] sockfd the socket to read from 168 * \param[in] fr the address of the client (if applicable) 169 * \param[in] *frlen the length of the client's addr (if applicable) 170 * \param[out] size the number of bytes that are read 171 * \return the data read 172 */ 173 uint8_t *ldns_udp_read_wire(int sockfd, size_t *size, struct sockaddr_storage *fr, socklen_t *frlen); 174 175 /** 176 * returns the native sockaddr representation from the rdf. 177 * \param[in] rd the ldns_rdf to operate on 178 * \param[in] port what port to use. 0 means; use default (53) 179 * \param[out] size what is the size of the sockaddr_storage 180 * \return struct sockaddr* the address in the format so other 181 * functions can use it (sendto) 182 */ 183 struct sockaddr_storage * ldns_rdf2native_sockaddr_storage(const ldns_rdf *rd, uint16_t port, size_t *size); 184 185 /** 186 * returns an rdf with the sockaddr info. works for ip4 and ip6 187 * \param[in] sock the struct sockaddr_storage to convert 188 * \param[in] port what port was used. When NULL this is not set 189 * \return ldns_rdf* wth the address 190 */ 191 ldns_rdf * ldns_sockaddr_storage2rdf(const struct sockaddr_storage *sock, uint16_t *port); 192 193 /** 194 * Prepares the resolver for an axfr query 195 * The query is sent and the answers can be read with ldns_axfr_next 196 * \param[in] resolver the resolver to use 197 * \param[in] domain the domain to exfr 198 * \param[in] c the class to use 199 * \return ldns_status the status of the transfer 200 */ 201 ldns_status ldns_axfr_start(ldns_resolver *resolver, const ldns_rdf *domain, ldns_rr_class c); 202 203 #ifdef __cplusplus 204 } 205 #endif 206 207 #endif /* LDNS_NET_H */ 208