1 |
/* |
2 |
firedns.c - firedns library |
3 |
Copyright (C) 2002 Ian Gulliver |
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|
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This file has been gutted and mucked with for use in BOPM - see the |
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real library at http://ares.penguinhosting.net/~ian/ before you judge |
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firedns based on this.. |
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|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of version 2 of the GNU General Public License as |
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published by the Free Software Foundation. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program; if not, write to the Free Software |
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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*/ |
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|
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#include "setup.h" |
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|
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#include <stdlib.h> |
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#include <time.h> |
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <poll.h> |
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#include <sys/time.h> |
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#include <netinet/in.h> |
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#include <arpa/inet.h> |
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#include <string.h> |
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#include <unistd.h> |
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#include <stdio.h> |
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#include <errno.h> |
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#include <fcntl.h> |
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|
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#include "compat.h" |
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#include "memory.h" |
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#include "firedns.h" |
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#include "config.h" |
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#include "list.h" |
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#include "log.h" |
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#include "dnsbl.h" |
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|
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#define FIREDNS_TRIES 3 |
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|
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int firedns_errno = FDNS_ERR_NONE; |
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|
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/* Variables local to this file */ |
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static unsigned int firedns_fdinuse; |
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|
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/* up to FDNS_MAX nameservers; populated by firedns_init() */ |
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static struct in_addr servers4[FDNS_MAX]; |
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static struct in6_addr servers6[FDNS_MAX]; |
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/* actual count of nameservers; set by firedns_init() */ |
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static int i4; |
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static int i6; |
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|
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/* |
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* Linked list of open DNS queries; populated by firedns_add_query(), |
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* decimated by firedns_getresult() |
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*/ |
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static list_t *CONNECTIONS; |
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|
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/* |
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* List of errors, in order of values used in FDNS_ERR_*, returned by |
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* firedns_strerror |
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*/ |
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static const char *errors[] = |
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{ |
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"Success", |
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"Format error", |
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"Server failure", |
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"Name error", |
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"Not implemented", |
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"Refused", |
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"Timeout", |
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"Network error", |
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"FD Limit reached", |
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"Unknown error" |
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}; |
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|
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/* Structures */ |
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|
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/* open DNS query */ |
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struct s_connection |
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{ |
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/* |
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* unique ID (random number), matches header ID; both set by |
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* firedns_add_query() |
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*/ |
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unsigned char id[2]; |
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uint16_t class; |
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uint16_t type; |
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|
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/* file descriptor returned from sockets */ |
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int fd; |
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void *info; |
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time_t start; |
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char lookup[256]; |
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int v6; |
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}; |
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|
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struct s_rr_middle |
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{ |
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uint16_t type; |
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uint16_t class; |
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|
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/* XXX - firedns depends on this being 4 bytes */ |
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uint32_t ttl; |
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uint16_t rdlength; |
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}; |
115 |
|
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/* DNS query header */ |
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struct s_header |
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{ |
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unsigned char id[2]; |
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unsigned char flags1; |
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#define FLAGS1_MASK_QR 0x80 |
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/* bitshift right 3 */ |
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#define FLAGS1_MASK_OPCODE 0x78 |
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#define FLAGS1_MASK_AA 0x04 |
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#define FLAGS1_MASK_TC 0x02 |
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#define FLAGS1_MASK_RD 0x01 |
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|
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unsigned char flags2; |
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#define FLAGS2_MASK_RA 0x80 |
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#define FLAGS2_MASK_Z 0x70 |
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#define FLAGS2_MASK_RCODE 0x0f |
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|
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uint16_t qdcount; |
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uint16_t ancount; |
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uint16_t nscount; |
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uint16_t arcount; |
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|
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/* DNS question, populated by firedns_build_query_payload() */ |
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unsigned char payload[512]; |
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}; |
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|
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/* Function prototypes */ |
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static struct s_connection *firedns_add_query(void); |
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static int firedns_doquery(struct s_connection *); |
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static int firedns_build_query_payload(const char *const, uint16_t, uint16_t, unsigned char *); |
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static int firedns_send_requests(struct s_header *, struct s_connection *, int); |
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|
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|
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void |
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firedns_init(void) |
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{ |
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/* |
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* populates servers4 (or -6) struct with up to FDNS_MAX nameserver IP |
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* addresses from /etc/firedns.conf (or /etc/resolv.conf) |
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*/ |
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FILE *f; |
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int i; |
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struct in_addr addr4; |
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struct in6_addr addr6; |
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char buf[1024]; |
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char *p = NULL; |
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|
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i6 = 0; |
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i4 = 0; |
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|
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/* Initialize connections list */ |
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CONNECTIONS = list_create(); |
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|
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srand((unsigned int)time(NULL)); |
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memset(servers4, 0, sizeof(struct in_addr) * FDNS_MAX); |
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memset(servers6, 0, sizeof(struct in6_addr) * FDNS_MAX); |
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|
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/* read etc/firedns.conf if we've got it, otherwise parse /etc/resolv.conf */ |
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f = fopen(FDNS_CONFIG_PREF, "r"); |
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|
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if (f == NULL) |
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{ |
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f = fopen(FDNS_CONFIG_FBCK, "r"); |
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|
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if (f == NULL) |
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{ |
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log_printf("Unable to open %s", FDNS_CONFIG_FBCK); |
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return; |
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} |
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|
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while (fgets(buf, sizeof(buf), f)) |
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{ |
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if ((p = strchr(buf, '\n'))) |
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*p = '\0'; |
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|
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if (strncmp(buf, "nameserver", 10) == 0) |
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{ |
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i = 10; |
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|
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while (buf[i] == ' ' || buf[i] == '\t') |
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++i; |
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|
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if (i6 < FDNS_MAX) |
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{ |
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if (inet_pton(AF_INET6, &buf[i], &addr6) > 0) |
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{ |
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memcpy(&servers6[i6++], &addr6, sizeof(struct in6_addr)); |
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continue; |
204 |
} |
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} |
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|
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if (i4 < FDNS_MAX) |
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{ |
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if (inet_pton(AF_INET, &buf[i], &addr4) > 0) |
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memcpy(&servers4[i4++], &addr4, sizeof(struct in_addr)); |
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} |
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} |
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} |
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} |
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else |
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{ |
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while (fgets(buf, sizeof(buf), f)) |
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{ |
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if ((p = strchr(buf, '\n'))) |
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*p = '\0'; |
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|
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if (i6 < FDNS_MAX) |
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{ |
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if (inet_pton(AF_INET6, buf, &addr6) > 0) |
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{ |
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memcpy(&servers6[i6++], &addr6, sizeof(struct in6_addr)); |
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continue; |
228 |
} |
229 |
} |
230 |
|
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if (i4 < FDNS_MAX) |
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{ |
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if (inet_pton(AF_INET, buf, &addr4) > 0) |
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memcpy(&servers4[i4++], &addr4, sizeof(struct in_addr)); |
235 |
} |
236 |
} |
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} |
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|
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fclose(f); |
240 |
} |
241 |
|
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/* immediate A query */ |
243 |
struct in_addr * |
244 |
firedns_resolveip4(const char *const name) |
245 |
{ |
246 |
static struct in_addr addr; |
247 |
|
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if (inet_pton(AF_INET, name, &addr) > 0) |
249 |
return &addr; |
250 |
|
251 |
return (struct in_addr *)firedns_resolveip(FDNS_QRY_A, name); |
252 |
} |
253 |
|
254 |
/* immediate AAAA query */ |
255 |
struct in6_addr * |
256 |
firedns_resolveip6(const char * const name) |
257 |
{ |
258 |
static struct in6_addr addr; |
259 |
|
260 |
if (inet_pton(AF_INET6, name, &addr) > 0) |
261 |
return &addr; |
262 |
|
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return (struct in6_addr *)firedns_resolveip(FDNS_QRY_AAAA, name); |
264 |
} |
265 |
|
266 |
/* resolve a query of a given type */ |
267 |
char * |
268 |
firedns_resolveip(int type, const char *const name) |
269 |
{ |
270 |
struct firedns_result *result; |
271 |
struct timeval tv; |
272 |
fd_set s; |
273 |
|
274 |
for (int t = 0; t < FIREDNS_TRIES; ++t) |
275 |
{ |
276 |
int fd = firedns_getip(type, name, NULL); |
277 |
|
278 |
if (fd == -1) |
279 |
return NULL; |
280 |
|
281 |
tv.tv_sec = 5; |
282 |
tv.tv_usec = 0; |
283 |
FD_ZERO(&s); |
284 |
FD_SET(fd, &s); |
285 |
select(fd + 1, &s, NULL, NULL, &tv); |
286 |
|
287 |
result = firedns_getresult(fd); |
288 |
|
289 |
if (firedns_errno == FDNS_ERR_NONE) |
290 |
/* |
291 |
* Return is from static memory in getresult, so there is no need to |
292 |
* copy it until the next call to firedns. |
293 |
*/ |
294 |
return result->text; |
295 |
else if (firedns_errno == FDNS_ERR_NXDOMAIN) |
296 |
return NULL; |
297 |
} |
298 |
|
299 |
if (firedns_errno == FDNS_ERR_NONE) |
300 |
firedns_errno = FDNS_ERR_TIMEOUT; |
301 |
|
302 |
return NULL; |
303 |
} |
304 |
|
305 |
/* |
306 |
* build, add and send specified query; retrieve result with |
307 |
* firedns_getresult() |
308 |
*/ |
309 |
int |
310 |
firedns_getip(int type, const char * const name, void *info) |
311 |
{ |
312 |
struct s_connection *s; |
313 |
node_t *node; |
314 |
int fd; |
315 |
|
316 |
s = firedns_add_query(); |
317 |
s->class = 1; |
318 |
s->type = type; |
319 |
s->info = info; |
320 |
strlcpy(s->lookup, name, sizeof(s->lookup)); |
321 |
|
322 |
if (firedns_fdinuse >= OptionsItem->dns_fdlimit) |
323 |
{ |
324 |
firedns_errno = FDNS_ERR_FDLIMIT; |
325 |
|
326 |
/* Don't add to queue if there is no info */ |
327 |
if (info == NULL) |
328 |
xfree(s); |
329 |
else |
330 |
{ |
331 |
node = node_create(s); |
332 |
list_add(CONNECTIONS, node); |
333 |
} |
334 |
|
335 |
return -1; |
336 |
} |
337 |
|
338 |
fd = firedns_doquery(s); |
339 |
|
340 |
if (fd == -1) |
341 |
{ |
342 |
xfree(s); |
343 |
return -1; |
344 |
} |
345 |
|
346 |
node = node_create(s); |
347 |
list_add(CONNECTIONS, node); |
348 |
|
349 |
return fd; |
350 |
} |
351 |
|
352 |
/* build DNS query, add to list */ |
353 |
static struct s_connection * |
354 |
firedns_add_query(void) |
355 |
{ |
356 |
struct s_connection *s; |
357 |
|
358 |
/* create new connection object */ |
359 |
s = xcalloc(sizeof *s); |
360 |
|
361 |
/* verified by firedns_getresult() */ |
362 |
s->id[0] = rand() % 255; |
363 |
s->id[1] = rand() % 255; |
364 |
s->fd = -1; |
365 |
|
366 |
return s; |
367 |
} |
368 |
|
369 |
static int |
370 |
firedns_doquery(struct s_connection *s) |
371 |
{ |
372 |
int len; |
373 |
struct s_header h; |
374 |
|
375 |
len = firedns_build_query_payload(s->lookup, s->type, 1, (unsigned char *)&h.payload); |
376 |
|
377 |
if (len == -1) |
378 |
{ |
379 |
firedns_errno = FDNS_ERR_FORMAT; |
380 |
return -1; |
381 |
} |
382 |
|
383 |
return firedns_send_requests(&h, s, len); |
384 |
} |
385 |
|
386 |
/* |
387 |
* populate payload with query: name= question, rr= record type |
388 |
*/ |
389 |
static int |
390 |
firedns_build_query_payload(const char *const name, uint16_t rr, uint16_t class, |
391 |
unsigned char *payload) |
392 |
{ |
393 |
int16_t payloadpos = 0; |
394 |
const char *tempchr, *tempchr2; |
395 |
uint16_t l; |
396 |
|
397 |
tempchr2 = name; |
398 |
|
399 |
/* split name up into labels, create query */ |
400 |
while ((tempchr = strchr(tempchr2, '.'))) |
401 |
{ |
402 |
l = tempchr - tempchr2; |
403 |
|
404 |
if (payloadpos + l + 1 > 507) |
405 |
return -1; |
406 |
|
407 |
payload[payloadpos++] = l; |
408 |
memcpy(&payload[payloadpos], tempchr2, l); |
409 |
payloadpos += l; |
410 |
tempchr2 = &tempchr[1]; |
411 |
} |
412 |
|
413 |
l = strlen(tempchr2); |
414 |
|
415 |
if (l) |
416 |
{ |
417 |
if (payloadpos + l + 2 > 507) |
418 |
return -1; |
419 |
|
420 |
payload[payloadpos++] = l; |
421 |
memcpy(&payload[payloadpos], tempchr2, l); |
422 |
payloadpos += l; |
423 |
payload[payloadpos++] = '\0'; |
424 |
} |
425 |
|
426 |
if (payloadpos > 508) |
427 |
return -1; |
428 |
|
429 |
l = htons(rr); |
430 |
memcpy(&payload[payloadpos], &l, 2); |
431 |
|
432 |
l = htons(class); |
433 |
memcpy(&payload[payloadpos + 2], &l, 2); |
434 |
|
435 |
return payloadpos + 4; |
436 |
} |
437 |
|
438 |
/* send DNS query */ |
439 |
static int |
440 |
firedns_send_requests(struct s_header *h, struct s_connection *s, int l) |
441 |
{ |
442 |
int i, sent_ok = 0; |
443 |
struct sockaddr_in addr4; |
444 |
struct sockaddr_in6 addr6; |
445 |
|
446 |
/* set header flags */ |
447 |
h->flags1 = 0 | FLAGS1_MASK_RD; |
448 |
h->flags2 = 0; |
449 |
h->qdcount = htons(1); |
450 |
h->ancount = htons(0); |
451 |
h->nscount = htons(0); |
452 |
h->arcount = htons(0); |
453 |
memcpy(h->id, s->id, 2); |
454 |
|
455 |
/* try to create ipv6 or ipv4 socket */ |
456 |
s->v6 = 0; |
457 |
|
458 |
if (i6 > 0) |
459 |
{ |
460 |
s->fd = socket(PF_INET6, SOCK_DGRAM, 0); |
461 |
|
462 |
if (s->fd != -1) |
463 |
{ |
464 |
if (fcntl(s->fd, F_SETFL, O_NONBLOCK)) |
465 |
{ |
466 |
close(s->fd); |
467 |
s->fd = -1; |
468 |
} |
469 |
} |
470 |
|
471 |
if (s->fd != -1) |
472 |
{ |
473 |
struct sockaddr_in6 addr6; |
474 |
|
475 |
memset(&addr6, 0, sizeof(addr6)); |
476 |
addr6.sin6_family = AF_INET6; |
477 |
|
478 |
if (bind(s->fd, (struct sockaddr *)&addr6, sizeof(addr6)) == 0) |
479 |
s->v6 = 1; |
480 |
else |
481 |
close(s->fd); |
482 |
} |
483 |
} |
484 |
|
485 |
if (s->v6 == 0) |
486 |
{ |
487 |
s->fd = socket(PF_INET, SOCK_DGRAM, 0); |
488 |
|
489 |
if (s->fd != -1) |
490 |
{ |
491 |
if (fcntl(s->fd, F_SETFL, O_NONBLOCK)) |
492 |
{ |
493 |
close(s->fd); |
494 |
s->fd = -1; |
495 |
} |
496 |
} |
497 |
|
498 |
if (s->fd != -1) |
499 |
{ |
500 |
struct sockaddr_in addr; |
501 |
|
502 |
memset(&addr, 0, sizeof(addr)); |
503 |
addr.sin_family = AF_INET; |
504 |
addr.sin_port = 0; |
505 |
addr.sin_addr.s_addr = INADDR_ANY; |
506 |
|
507 |
if (bind(s->fd, (struct sockaddr *)&addr, sizeof(addr)) != 0) |
508 |
{ |
509 |
close(s->fd); |
510 |
s->fd = -1; |
511 |
} |
512 |
} |
513 |
|
514 |
if (s->fd == -1) |
515 |
{ |
516 |
firedns_errno = FDNS_ERR_NETWORK; |
517 |
return -1; |
518 |
} |
519 |
} |
520 |
|
521 |
/* if we've got ipv6 support, an ip v6 socket, and ipv6 servers, send to them */ |
522 |
if (i6 > 0 && s->v6 == 1) |
523 |
{ |
524 |
for (i = 0; i < i6; i++) |
525 |
{ |
526 |
memset(&addr6, 0, sizeof(addr6)); |
527 |
memcpy(&addr6.sin6_addr, &servers6[i], sizeof(addr6.sin6_addr)); |
528 |
|
529 |
addr6.sin6_family = AF_INET6; |
530 |
addr6.sin6_port = htons(FDNS_PORT); |
531 |
|
532 |
if (sendto(s->fd, h, l + 12, 0, (struct sockaddr *)&addr6, sizeof(addr6)) > 0) |
533 |
sent_ok = 1; |
534 |
} |
535 |
} |
536 |
|
537 |
for (i = 0; i < i4; i++) |
538 |
{ |
539 |
/* send via ipv4-over-ipv6 if we've got an ipv6 socket */ |
540 |
if (s->v6 == 1) |
541 |
{ |
542 |
memset(&addr6, 0, sizeof(addr6)); |
543 |
memcpy(addr6.sin6_addr.s6_addr, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12); |
544 |
memcpy(&addr6.sin6_addr.s6_addr[12], &servers4[i].s_addr, 4); |
545 |
addr6.sin6_family = AF_INET6; |
546 |
addr6.sin6_port = htons(FDNS_PORT); |
547 |
|
548 |
if (sendto(s->fd, h, l + 12, 0, (struct sockaddr *)&addr6, sizeof(addr6)) > 0) |
549 |
sent_ok = 1; |
550 |
|
551 |
continue; |
552 |
} |
553 |
|
554 |
/* otherwise send via standard ipv4 boringness */ |
555 |
memset(&addr4, 0, sizeof(addr4)); |
556 |
memcpy(&addr4.sin_addr, &servers4[i], sizeof(addr4.sin_addr)); |
557 |
addr4.sin_family = AF_INET; |
558 |
addr4.sin_port = htons(FDNS_PORT); |
559 |
|
560 |
if (sendto(s->fd, h, l + 12, 0, (struct sockaddr *)&addr4, sizeof(addr4)) > 0) |
561 |
sent_ok = 1; |
562 |
} |
563 |
|
564 |
if (!sent_ok) |
565 |
{ |
566 |
close(s->fd); |
567 |
s->fd = -1; |
568 |
firedns_errno = FDNS_ERR_NETWORK; |
569 |
return -1; |
570 |
} |
571 |
|
572 |
time(&s->start); |
573 |
firedns_fdinuse++; |
574 |
firedns_errno = FDNS_ERR_NONE; |
575 |
|
576 |
return s->fd; |
577 |
} |
578 |
|
579 |
/* retrieve result of DNS query */ |
580 |
struct firedns_result * |
581 |
firedns_getresult(const int fd) |
582 |
{ |
583 |
static struct firedns_result result; |
584 |
struct s_header h; |
585 |
struct s_connection *c; |
586 |
node_t *node; |
587 |
int l, i, q, curanswer; |
588 |
struct s_rr_middle *rr, rrbacking; |
589 |
char *src, *dst; |
590 |
int bytes; |
591 |
|
592 |
firedns_errno = FDNS_ERR_OTHER; |
593 |
result.info = NULL; |
594 |
|
595 |
memset(result.text, 0, sizeof(result.text)); |
596 |
|
597 |
/* Find query in list of dns lookups */ |
598 |
LIST_FOREACH(node, CONNECTIONS->head) |
599 |
{ |
600 |
c = node->data; |
601 |
|
602 |
if (c->fd == fd) |
603 |
break; |
604 |
else |
605 |
c = NULL; |
606 |
} |
607 |
|
608 |
/* query not found */ |
609 |
if (c == NULL) |
610 |
return &result; |
611 |
|
612 |
/* query found -- we remove in cleanup */ |
613 |
l = recv(c->fd, &h,sizeof(struct s_header), 0); |
614 |
result.info = c->info; |
615 |
strlcpy(result.lookup, c->lookup, sizeof(result.lookup)); |
616 |
|
617 |
if (l == -1) |
618 |
{ |
619 |
firedns_errno = FDNS_ERR_NETWORK; |
620 |
goto cleanup; |
621 |
} |
622 |
|
623 |
if (l < 12) |
624 |
goto cleanup; |
625 |
|
626 |
if (c->id[0] != h.id[0] || c->id[1] != h.id[1]) |
627 |
/* |
628 |
* ID mismatch: we keep the connection, as this could be an answer to |
629 |
* a previous lookup.. |
630 |
*/ |
631 |
return NULL; |
632 |
|
633 |
if ((h.flags1 & FLAGS1_MASK_QR) == 0) |
634 |
goto cleanup; |
635 |
|
636 |
if ((h.flags1 & FLAGS1_MASK_OPCODE) != 0) |
637 |
goto cleanup; |
638 |
|
639 |
if ((h.flags2 & FLAGS2_MASK_RCODE) != 0) |
640 |
{ |
641 |
firedns_errno = (h.flags2 & FLAGS2_MASK_RCODE); |
642 |
goto cleanup; |
643 |
} |
644 |
|
645 |
h.ancount = ntohs(h.ancount); |
646 |
|
647 |
if (h.ancount < 1) |
648 |
{ |
649 |
firedns_errno = FDNS_ERR_NXDOMAIN; |
650 |
/* no sense going on if we don't have any answers */ |
651 |
goto cleanup; |
652 |
} |
653 |
|
654 |
/* skip queries */ |
655 |
i = 0; |
656 |
q = 0; |
657 |
l -= 12; |
658 |
h.qdcount = ntohs(h.qdcount); |
659 |
|
660 |
while (q < h.qdcount && i < l) |
661 |
{ |
662 |
if (h.payload[i] > 63) |
663 |
{ |
664 |
/* pointer */ |
665 |
i += 6; /* skip pointer, class and type */ |
666 |
q++; |
667 |
} |
668 |
else |
669 |
{ |
670 |
/* label */ |
671 |
if (h.payload[i] == 0) |
672 |
{ |
673 |
q++; |
674 |
i += 5; /* skip nil, class and type */ |
675 |
} |
676 |
else |
677 |
i += h.payload[i] + 1; /* skip length and label */ |
678 |
} |
679 |
} |
680 |
|
681 |
/* &h.payload[i] should now be the start of the first response */ |
682 |
curanswer = 0; |
683 |
|
684 |
while (curanswer < h.ancount) |
685 |
{ |
686 |
q = 0; |
687 |
|
688 |
while (q == 0 && i < l) |
689 |
{ |
690 |
if (h.payload[i] > 63) |
691 |
{ |
692 |
/* pointer */ |
693 |
i += 2; /* skip pointer */ |
694 |
q = 1; |
695 |
} |
696 |
else |
697 |
{ |
698 |
/* label */ |
699 |
if (h.payload[i] == 0) |
700 |
{ |
701 |
i++; |
702 |
q = 1; |
703 |
} |
704 |
else |
705 |
i += h.payload[i] + 1; /* skip length and label */ |
706 |
} |
707 |
} |
708 |
|
709 |
if (l - i < 10) |
710 |
goto cleanup; |
711 |
|
712 |
rr = (struct s_rr_middle *)&h.payload[i]; |
713 |
src = (char *)rr; |
714 |
dst = (char *)&rrbacking; |
715 |
|
716 |
for (bytes = sizeof(rrbacking); bytes; bytes--) |
717 |
*dst++ = *src++; |
718 |
|
719 |
rr = &rrbacking; |
720 |
i += 10; |
721 |
rr->rdlength = ntohs(rr->rdlength); |
722 |
|
723 |
if (ntohs(rr->type) != c->type) |
724 |
{ |
725 |
curanswer++; |
726 |
i += rr->rdlength; |
727 |
continue; |
728 |
} |
729 |
|
730 |
if (ntohs(rr->class) != c->class) |
731 |
{ |
732 |
curanswer++; |
733 |
i += rr->rdlength; |
734 |
continue; |
735 |
} |
736 |
|
737 |
break; |
738 |
} |
739 |
|
740 |
if (curanswer == h.ancount) |
741 |
goto cleanup; |
742 |
if (i + rr->rdlength > l) |
743 |
goto cleanup; |
744 |
if (rr->rdlength > 1023) |
745 |
goto cleanup; |
746 |
|
747 |
firedns_errno = FDNS_ERR_NONE; |
748 |
memcpy(result.text, &h.payload[i], rr->rdlength); |
749 |
result.text[rr->rdlength] = '\0'; |
750 |
|
751 |
/* Clean-up */ |
752 |
cleanup: |
753 |
list_remove(CONNECTIONS, node); |
754 |
node_free(node); |
755 |
close(c->fd); |
756 |
firedns_fdinuse--; |
757 |
xfree(c); |
758 |
|
759 |
return &result; |
760 |
} |
761 |
|
762 |
void |
763 |
firedns_cycle(void) |
764 |
{ |
765 |
node_t *node, *node_next; |
766 |
struct s_connection *p; |
767 |
struct firedns_result *res, new_result; |
768 |
static struct pollfd *ufds = NULL; |
769 |
int fd; |
770 |
unsigned int size, i; |
771 |
time_t timenow; |
772 |
|
773 |
if (LIST_SIZE(CONNECTIONS) == 0) |
774 |
return; |
775 |
|
776 |
if (ufds == NULL) |
777 |
ufds = xcalloc((sizeof *ufds) * OptionsItem->dns_fdlimit); |
778 |
|
779 |
time(&timenow); |
780 |
size = 0; |
781 |
|
782 |
LIST_FOREACH_SAFE(node, node_next, CONNECTIONS->head) |
783 |
{ |
784 |
if (size >= OptionsItem->dns_fdlimit) |
785 |
break; |
786 |
|
787 |
p = node->data; |
788 |
|
789 |
if (p->fd < 0) |
790 |
continue; |
791 |
|
792 |
if (p->fd > 0 && (p->start + FDNS_TIMEOUT) < timenow) |
793 |
{ |
794 |
/* Timed out - remove from list */ |
795 |
list_remove(CONNECTIONS, node); |
796 |
node_free(node); |
797 |
|
798 |
memset(new_result.text, 0, sizeof(new_result.text)); |
799 |
new_result.info = p->info; |
800 |
strlcpy(new_result.lookup, p->lookup, sizeof(new_result.lookup)); |
801 |
|
802 |
close(p->fd); |
803 |
firedns_fdinuse--; |
804 |
xfree(p); |
805 |
|
806 |
firedns_errno = FDNS_ERR_TIMEOUT; |
807 |
|
808 |
if (new_result.info) |
809 |
dnsbl_result(&new_result); |
810 |
|
811 |
continue; |
812 |
} |
813 |
|
814 |
ufds[size].events = 0; |
815 |
ufds[size].revents = 0; |
816 |
ufds[size].fd = p->fd; |
817 |
ufds[size].events = POLLIN; |
818 |
|
819 |
++size; |
820 |
} |
821 |
|
822 |
switch (poll(ufds, size, 0)) |
823 |
{ |
824 |
case -1: |
825 |
case 0: |
826 |
return; |
827 |
} |
828 |
|
829 |
LIST_FOREACH_SAFE(node, node_next, CONNECTIONS->head) |
830 |
{ |
831 |
p = node->data; |
832 |
|
833 |
if (p->fd > 0) |
834 |
{ |
835 |
for (i = 0; i < size; ++i) |
836 |
{ |
837 |
if ((ufds[i].revents & POLLIN) && ufds[i].fd == p->fd) |
838 |
{ |
839 |
fd = p->fd; |
840 |
res = firedns_getresult(fd); |
841 |
|
842 |
if (res && res->info) |
843 |
dnsbl_result(res); |
844 |
|
845 |
break; |
846 |
} |
847 |
} |
848 |
} |
849 |
else if (firedns_fdinuse < OptionsItem->dns_fdlimit) |
850 |
firedns_doquery(p); |
851 |
} |
852 |
} |
853 |
|
854 |
const char * |
855 |
firedns_strerror(int error) |
856 |
{ |
857 |
if (error == FDNS_ERR_NETWORK) |
858 |
return strerror(errno); |
859 |
|
860 |
return errors[error]; |
861 |
} |