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 response 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 or -1 on failure 52 */ 53 int ldns_udp_bgsend2(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 54 55 /** 56 * Send an udp query and don't wait for an answer but return 57 * the socket 58 * This function has the flaw that it returns 0 on failure, but 0 could be a 59 * valid socket. Please use ldns_udp_bgsend2 instead of this function. 60 * \param[in] qbin the ldns_buffer to be send 61 * \param[in] to the ip addr to send to 62 * \param[in] tolen length of the ip addr 63 * \param[in] timeout *unused*, was the timeout value for the network 64 * \return the socket used or 0 on failure 65 */ 66 int ldns_udp_bgsend(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 67 68 /** 69 * Send an tcp query and don't wait for an answer but return 70 * the socket 71 * \param[in] qbin the ldns_buffer to be send 72 * \param[in] to the ip addr to send to 73 * \param[in] tolen length of the ip addr 74 * \param[in] timeout the timeout value for the connect attempt 75 * \return the socket used or -1 on failure 76 */ 77 int ldns_tcp_bgsend2(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 78 79 /** 80 * Send an tcp query and don't wait for an answer but return 81 * the socket 82 * This function has the flaw that it returns 0 on failure, but 0 could be a 83 * valid socket. Please use ldns_tcp_bgsend2 instead of this function. 84 * \param[in] qbin the ldns_buffer to be send 85 * \param[in] to the ip addr to send to 86 * \param[in] tolen length of the ip addr 87 * \param[in] timeout the timeout value for the connect attempt 88 * \return the socket used or 0 on failure 89 */ 90 int ldns_tcp_bgsend(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 91 92 /** 93 * Sends a buffer to an ip using tcp and return the response as a ldns_pkt 94 * \param[in] qbin the ldns_buffer to be send 95 * \param[in] qbin the ldns_buffer to be send 96 * \param[in] to the ip addr to send to 97 * \param[in] tolen length of the ip addr 98 * \param[in] timeout the timeout value for the network 99 * \param[out] answersize size of the packet 100 * \param[out] result packet with the answer 101 * \return status 102 */ 103 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); 104 105 /** 106 * Sends ptk to the nameserver at the resolver object. Returns the data 107 * as a ldns_pkt 108 * 109 * \param[out] pkt packet received from the nameserver 110 * \param[in] r the resolver to use 111 * \param[in] query_pkt the query to send 112 * \return status 113 */ 114 ldns_status ldns_send(ldns_pkt **pkt, ldns_resolver *r, const ldns_pkt *query_pkt); 115 116 /** 117 * Sends and ldns_buffer (presumably containing a packet to the nameserver at the resolver object. Returns the data 118 * as a ldns_pkt 119 * 120 * \param[out] pkt packet received from the nameserver 121 * \param[in] r the resolver to use 122 * \param[in] qb the buffer to send 123 * \param[in] tsig_mac the tsig MAC to authenticate the response with (NULL to do no TSIG authentication) 124 * \return status 125 */ 126 ldns_status ldns_send_buffer(ldns_pkt **pkt, ldns_resolver *r, ldns_buffer *qb, ldns_rdf *tsig_mac); 127 128 /** 129 * Create a tcp socket to the specified address 130 * \param[in] to ip and family 131 * \param[in] tolen length of to 132 * \param[in] timeout timeout for the connect attempt 133 * \return a socket descriptor or -1 on failure 134 */ 135 int ldns_tcp_connect2(const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 136 137 /** 138 * Create a tcp socket to the specified address 139 * This function has the flaw that it returns 0 on failure, but 0 could be a 140 * valid socket. Please use ldns_tcp_connect2 instead of this function. 141 * \param[in] to ip and family 142 * \param[in] tolen length of to 143 * \param[in] timeout timeout for the connect attempt 144 * \return a socket descriptor or 0 on failure 145 */ 146 int ldns_tcp_connect(const struct sockaddr_storage *to, socklen_t tolen, struct timeval timeout); 147 148 /** 149 * Create a udp socket to the specified address 150 * \param[in] to ip and family 151 * \param[in] timeout *unused*, was timeout for the socket 152 * \return a socket descriptor or -1 on failure 153 */ 154 int ldns_udp_connect2(const struct sockaddr_storage *to, struct timeval timeout); 155 156 /** 157 * Create a udp socket to the specified address 158 * This function has the flaw that it returns 0 on failure, but 0 could be a 159 * valid socket. Please use ldns_udp_connect2 instead of this function. 160 * \param[in] to ip and family 161 * \param[in] timeout *unused*, was timeout for the socket 162 * \return a socket descriptor or 0 on failure 163 */ 164 int ldns_udp_connect(const struct sockaddr_storage *to, struct timeval timeout); 165 166 /** 167 * send a query via tcp to a server. Don't want for the answer 168 * 169 * \param[in] qbin the buffer to send 170 * \param[in] sockfd the socket to use 171 * \param[in] to which ip to send it 172 * \param[in] tolen socketlen 173 * \return number of bytes sent 174 */ 175 ssize_t ldns_tcp_send_query(ldns_buffer *qbin, int sockfd, const struct sockaddr_storage *to, socklen_t tolen); 176 177 /** 178 * send a query via udp to a server. Don;t want for the answer 179 * 180 * \param[in] qbin the buffer to send 181 * \param[in] sockfd the socket to use 182 * \param[in] to which ip to send it 183 * \param[in] tolen socketlen 184 * \return number of bytes sent 185 */ 186 ssize_t ldns_udp_send_query(ldns_buffer *qbin, int sockfd, const struct sockaddr_storage *to, socklen_t tolen); 187 188 /** 189 * Gives back a raw packet from the wire and reads the header data from the given 190 * socket. Allocates the data (of size size) itself, so don't forget to free 191 * 192 * \param[in] sockfd the socket to read from 193 * \param[out] size the number of bytes that are read 194 * \param[in] timeout the time allowed between packets. 195 * \return the data read 196 */ 197 uint8_t *ldns_tcp_read_wire_timeout(int sockfd, size_t *size, struct timeval timeout); 198 199 /** 200 * This routine may block. Use ldns_tcp_read_wire_timeout, it checks timeouts. 201 * Gives back a raw packet from the wire and reads the header data from the given 202 * socket. Allocates the data (of size size) itself, so don't forget to free 203 * 204 * \param[in] sockfd the socket to read from 205 * \param[out] size the number of bytes that are read 206 * \return the data read 207 */ 208 uint8_t *ldns_tcp_read_wire(int sockfd, size_t *size); 209 210 /** 211 * Gives back a raw packet from the wire and reads the header data from the given 212 * socket. Allocates the data (of size size) itself, so don't forget to free 213 * 214 * \param[in] sockfd the socket to read from 215 * \param[in] fr the address of the client (if applicable) 216 * \param[in] *frlen the length of the client's addr (if applicable) 217 * \param[out] size the number of bytes that are read 218 * \return the data read 219 */ 220 uint8_t *ldns_udp_read_wire(int sockfd, size_t *size, struct sockaddr_storage *fr, socklen_t *frlen); 221 222 /** 223 * returns the native sockaddr representation from the rdf. 224 * \param[in] rd the ldns_rdf to operate on 225 * \param[in] port what port to use. 0 means; use default (53) 226 * \param[out] size what is the size of the sockaddr_storage 227 * \return struct sockaddr* the address in the format so other 228 * functions can use it (sendto) 229 */ 230 struct sockaddr_storage * ldns_rdf2native_sockaddr_storage(const ldns_rdf *rd, uint16_t port, size_t *size); 231 232 /** 233 * returns an rdf with the sockaddr info. works for ip4 and ip6 234 * \param[in] sock the struct sockaddr_storage to convert 235 * \param[in] port what port was used. When NULL this is not set 236 * \return ldns_rdf* with the address 237 */ 238 ldns_rdf * ldns_sockaddr_storage2rdf(const struct sockaddr_storage *sock, uint16_t *port); 239 240 /** 241 * Prepares the resolver for an axfr query 242 * The query is sent and the answers can be read with ldns_axfr_next 243 * \param[in] resolver the resolver to use 244 * \param[in] domain the domain to axfr 245 * \param[in] c the class to use 246 * \return ldns_status the status of the transfer 247 */ 248 ldns_status ldns_axfr_start(ldns_resolver *resolver, const ldns_rdf *domain, ldns_rr_class c); 249 250 #ifdef __cplusplus 251 } 252 #endif 253 254 #endif /* LDNS_NET_H */ 255