/** Request the name (PTR) record for an IPv4 address. */ int dns_name4_r(struct dns_transmit* tx, struct dns_result* out, const ipv4addr *ip) { char name[DNS_NAME4_DOMAIN]; dns_name4_domain(name,ip); if (dns_resolve(tx,name,DNS_T_PTR) == -1) return -1; if (dns_name_packet(out,tx->packet,tx->packetlen) == -1) return -1; dns_transmit_free(tx); return 0; }
int main(int argc,char **argv) { struct taia stamp; struct taia deadline; int opt; unsigned long u; int i; int j; int r; while ((opt = getopt(argc,argv,"c:l:")) != opteof) switch(opt) { case 'c': scan_ulong(optarg,&u); if (u < 1) u = 1; if (u > 1000) u = 1000; maxactive = u; break; case 'l': scan_ulong(optarg,&u); if (u < 1) u = 1; if (u > 1000000) u = 1000000; xmax = u; break; default: strerr_die1x(111,"dnsfilter: usage: dnsfilter [ -c concurrency ] [ -l lines ]"); } x = (struct line *) alloc(xmax * sizeof(struct line)); if (!x) nomem(); byte_zero(x,xmax * sizeof(struct line)); io = (iopause_fd *) alloc((xmax + 1) * sizeof(iopause_fd)); if (!io) nomem(); if (!stralloc_copys(&partial,"")) nomem(); while (flag0 || inbuflen || partial.len || xnum) { taia_now(&stamp); taia_uint(&deadline,120); taia_add(&deadline,&deadline,&stamp); iolen = 0; if (flag0) if (inbuflen < sizeof inbuf) { inio = io + iolen++; inio->fd = 0; inio->events = IOPAUSE_READ; } for (i = 0;i < xnum;++i) if (x[i].flagactive) { x[i].io = io + iolen++; dns_transmit_io(&x[i].dt,x[i].io,&deadline); } iopause(io,iolen,&deadline,&stamp); if (flag0) if (inbuflen < sizeof inbuf) if (inio->revents) { r = read(0,inbuf + inbuflen,(sizeof inbuf) - inbuflen); if (r <= 0) flag0 = 0; else inbuflen += r; } for (i = 0;i < xnum;++i) if (x[i].flagactive) { r = dns_transmit_get(&x[i].dt,x[i].io,&stamp); if (r == -1) { errout(i); x[i].flagactive = 0; --numactive; } else if (r == 1) { if (dns_name_packet(&x[i].middle,x[i].dt.packet,x[i].dt.packetlen) == -1) errout(i); if (x[i].middle.len) if (!stralloc_cats(&x[i].left,"=")) nomem(); x[i].flagactive = 0; --numactive; } } for (;;) { if (xnum && !x[0].flagactive) { buffer_put(buffer_1,x[0].left.s,x[0].left.len); buffer_put(buffer_1,x[0].middle.s,x[0].middle.len); buffer_put(buffer_1,x[0].right.s,x[0].right.len); buffer_flush(buffer_1); --xnum; tmp = x[0]; for (i = 0;i < xnum;++i) x[i] = x[i + 1]; x[xnum] = tmp; continue; } if ((xnum < xmax) && (numactive < maxactive)) { i = byte_chr(inbuf,inbuflen,'\n'); if (inbuflen && (i == inbuflen)) { if (!stralloc_catb(&partial,inbuf,inbuflen)) nomem(); inbuflen = 0; continue; } if ((i < inbuflen) || (!flag0 && partial.len)) { if (i < inbuflen) ++i; if (!stralloc_catb(&partial,inbuf,i)) nomem(); inbuflen -= i; for (j = 0;j < inbuflen;++j) inbuf[j] = inbuf[j + i]; if (partial.len) { i = byte_chr(partial.s,partial.len,'\n'); i = byte_chr(partial.s,i,'\t'); i = byte_chr(partial.s,i,' '); if (!stralloc_copyb(&x[xnum].left,partial.s,i)) nomem(); if (!stralloc_copys(&x[xnum].middle,"")) nomem(); if (!stralloc_copyb(&x[xnum].right,partial.s + i,partial.len - i)) nomem(); x[xnum].flagactive = 0; partial.len = i; if (!stralloc_0(&partial)) nomem(); if (ip4_scan(partial.s,ip)) { dns_name4_domain(name,ip); if (dns_resolvconfip(servers) == -1) strerr_die2sys(111,FATAL,"unable to read /etc/resolv.conf: "); if (dns_transmit_start(&x[xnum].dt,servers,1,name,DNS_T_PTR,"\0\0\0\0") == -1) errout(xnum); else { x[xnum].flagactive = 1; ++numactive; } } ++xnum; } partial.len = 0; continue; } } break; } } _exit(0); }