static int thistcp (struct dns_transmit *d) { struct taia now; const char *ip = NULL; socketfree (d); packetfree (d); for (; d->curserver < 16; ++d->curserver) { ip = d->servers + 4 * d->curserver; if (byte_diff (ip, 4, "\0\0\0\0")) { d->query[2] = dns_random (256); d->query[3] = dns_random (256); d->s1 = 1 + socket_tcp (); if (!d->s1) { dns_transmit_free (d); return -1; } if (randombind (d) == -1) { dns_transmit_free (d); return -1; } taia_now (&now); taia_uint (&d->deadline, 10); taia_add (&d->deadline, &d->deadline, &now); if (socket_connect4 (d->s1 - 1, ip, 53) == 0) { d->pos = 0; d->tcpstate = 2; return 0; } if (errno == error_inprogress || errno == error_wouldblock) { d->tcpstate = 1; return 0; } socketfree(d); } } dns_transmit_free(d); return -1; }
void dns_transmit_free (struct dns_transmit *d) { queryfree (d); socketfree (d); packetfree (d); }
static int thisudp(struct dns_transmit *d) { const char *ip; socketfree(d); while (d->udploop < 4) { for (;d->curserver < 16;++d->curserver) { ip = d->servers + 4 * d->curserver; if (byte_diff(ip,4,"\0\0\0\0")) { d->query[2] = dns_random(256); d->query[3] = dns_random(256); d->s1 = 1 + socket_udp(); if (!d->s1) { dns_transmit_free(d); return -1; } if (randombind(d) == -1) { dns_transmit_free(d); return -1; } if (socket_connect4(d->s1 - 1,ip,53) == 0) if (send(d->s1 - 1,d->query + 2,d->querylen - 2,0) == d->querylen - 2) { struct taia now; taia_now(&now); taia_uint(&d->deadline,timeouts[d->udploop]); taia_add(&d->deadline,&d->deadline,&now); d->tcpstate = 0; return 0; } socketfree(d); } } ++d->udploop; d->curserver = 0; } dns_transmit_free(d); return -1; }
static int thistcp(struct dns_transmit *d) { struct taia now; const char *ip; socketfree(d); packetfree(d); for (;d->curserver < 16;++d->curserver) { ip = d->servers + 16 * d->curserver; if (byte_diff(ip,16,V6any)) { d->query[2] = dns_random(256); d->query[3] = dns_random(256); d->s1 = 1 + socket_tcp6(); if (!d->s1) { dns_transmit_free(d); return -1; } if (randombind(d) == -1) { dns_transmit_free(d); return -1; } taia_now(&now); taia_uint(&d->deadline,10); taia_add(&d->deadline,&d->deadline,&now); if (socket_connect6(d->s1 - 1,ip,53,d->scope_id) == 0) { d->tcpstate = 2; return 0; } if ((errno == error_inprogress) || (errno == error_wouldblock)) { d->tcpstate = 1; return 0; } socketfree(d); } } dns_transmit_free(d); return -1; }
int dns_transmit_get(struct dns_transmit *d,const iopause_fd *x,const struct taia *when) { char udpbuf[513]; unsigned char ch; int r; int fd; errno = error_io; fd = d->s1 - 1; if (!x->revents) { if (taia_less(when,&d->deadline)) return 0; errno = error_timeout; if (d->tcpstate == 0) return nextudp(d); return nexttcp(d); } if (d->tcpstate == 0) { /* have attempted to send UDP query to each server udploop times have sent query to curserver on UDP socket s */ r = recv(fd,udpbuf,sizeof udpbuf,0); if (r <= 0) { if (errno == error_connrefused) if (d->udploop == 2) return 0; return nextudp(d); } if (r + 1 > sizeof udpbuf) return 0; if (irrelevant(d,udpbuf,r)) return 0; if (serverwantstcp(udpbuf,r)) return firsttcp(d); if (serverfailed(udpbuf,r)) { if (d->udploop == 2) return 0; return nextudp(d); } socketfree(d); d->packetlen = r; d->packet = alloc(d->packetlen); if (!d->packet) { dns_transmit_free(d); return -1; } byte_copy(d->packet,d->packetlen,udpbuf); queryfree(d); return 1; } if (d->tcpstate == 1) { /* have sent connection attempt to curserver on TCP socket s pos not defined */ if (!socket_connected(fd)) return nexttcp(d); d->pos = 0; d->tcpstate = 2; return 0; } if (d->tcpstate == 2) { /* have connection to curserver on TCP socket s have sent pos bytes of query */ r = write(fd,d->query + d->pos,d->querylen - d->pos); if (r <= 0) return nexttcp(d); d->pos += r; if (d->pos == d->querylen) { struct taia now; taia_now(&now); taia_uint(&d->deadline,10); taia_add(&d->deadline,&d->deadline,&now); d->tcpstate = 3; } return 0; } if (d->tcpstate == 3) { /* have sent entire query to curserver on TCP socket s pos not defined */ r = read(fd,&ch,1); if (r <= 0) return nexttcp(d); d->packetlen = ch; d->tcpstate = 4; return 0; } if (d->tcpstate == 4) { /* have sent entire query to curserver on TCP socket s pos not defined have received one byte of packet length into packetlen */ r = read(fd,&ch,1); if (r <= 0) return nexttcp(d); d->packetlen <<= 8; d->packetlen += ch; d->tcpstate = 5; d->pos = 0; d->packet = alloc(d->packetlen); if (!d->packet) { dns_transmit_free(d); return -1; } return 0; } if (d->tcpstate == 5) { /* have sent entire query to curserver on TCP socket s have received entire packet length into packetlen packet is allocated have received pos bytes of packet */ r = read(fd,d->packet + d->pos,d->packetlen - d->pos); if (r <= 0) return nexttcp(d); d->pos += r; if (d->pos < d->packetlen) return 0; socketfree(d); if (irrelevant(d,d->packet,d->packetlen)) return nexttcp(d); if (serverwantstcp(d->packet,d->packetlen)) return nexttcp(d); if (serverfailed(d->packet,d->packetlen)) return nexttcp(d); queryfree(d); return 1; } return 0; }
static int thisudp (struct dns_transmit *d) { const char *ip = NULL; socketfree (d); mergefree (d); while (d->udploop < 4) { for (; d->curserver < 16; ++d->curserver) { ip = d->servers + 4 * d->curserver; if (byte_diff (ip, 4, "\0\0\0\0")) { if (merge_enable && try_merge (d)) { if (merge_logger) merge_logger (ip, d->qtype, d->query + 14); return 0; } d->query[2] = dns_random (256); d->query[3] = dns_random (256); d->s1 = 1 + socket_udp (); if (!d->s1) { dns_transmit_free (d); return -1; } if (randombind (d) == -1) { dns_transmit_free (d); return -1; } if (socket_connect4 (d->s1 - 1, ip, 53) == 0) { if (send (d->s1 - 1, d->query + 2, d->querylen - 2, 0) == d->querylen - 2) { struct taia now; taia_now (&now); taia_uint (&d->deadline, timeouts[d->udploop]); taia_add (&d->deadline, &d->deadline, &now); d->tcpstate = 0; if (merge_enable) register_inprogress (d); return 0; } } socketfree (d); } } ++d->udploop; d->curserver = 0; } dns_transmit_free (d); return -1; }