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-rw-r--r--src/resolve/resolved-etc-hosts.c448
1 files changed, 0 insertions, 448 deletions
diff --git a/src/resolve/resolved-etc-hosts.c b/src/resolve/resolved-etc-hosts.c
deleted file mode 100644
index 40d650949d..0000000000
--- a/src/resolve/resolved-etc-hosts.c
+++ /dev/null
@@ -1,448 +0,0 @@
-/***
- This file is part of systemd.
-
- Copyright 2016 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include "fd-util.h"
-#include "fileio.h"
-#include "hostname-util.h"
-#include "resolved-etc-hosts.h"
-#include "resolved-dns-synthesize.h"
-#include "string-util.h"
-#include "strv.h"
-#include "time-util.h"
-
-/* Recheck /etc/hosts at most once every 2s */
-#define ETC_HOSTS_RECHECK_USEC (2*USEC_PER_SEC)
-
-typedef struct EtcHostsItem {
- int family;
- union in_addr_union address;
-
- char **names;
-} EtcHostsItem;
-
-typedef struct EtcHostsItemByName {
- char *name;
-
- EtcHostsItem **items;
- size_t n_items, n_allocated;
-} EtcHostsItemByName;
-
-void manager_etc_hosts_flush(Manager *m) {
- EtcHostsItem *item;
- EtcHostsItemByName *bn;
-
- while ((item = set_steal_first(m->etc_hosts_by_address))) {
- strv_free(item->names);
- free(item);
- }
-
- while ((bn = hashmap_steal_first(m->etc_hosts_by_name))) {
- free(bn->name);
- free(bn->items);
- free(bn);
- }
-
- m->etc_hosts_by_address = set_free(m->etc_hosts_by_address);
- m->etc_hosts_by_name = hashmap_free(m->etc_hosts_by_name);
-
- m->etc_hosts_mtime = USEC_INFINITY;
-}
-
-static void etc_hosts_item_hash_func(const void *p, struct siphash *state) {
- const EtcHostsItem *item = p;
-
- siphash24_compress(&item->family, sizeof(item->family), state);
-
- if (item->family == AF_INET)
- siphash24_compress(&item->address.in, sizeof(item->address.in), state);
- else if (item->family == AF_INET6)
- siphash24_compress(&item->address.in6, sizeof(item->address.in6), state);
-}
-
-static int etc_hosts_item_compare_func(const void *a, const void *b) {
- const EtcHostsItem *x = a, *y = b;
-
- if (x->family != y->family)
- return x->family - y->family;
-
- if (x->family == AF_INET)
- return memcmp(&x->address.in.s_addr, &y->address.in.s_addr, sizeof(struct in_addr));
-
- if (x->family == AF_INET6)
- return memcmp(&x->address.in6.s6_addr, &y->address.in6.s6_addr, sizeof(struct in6_addr));
-
- return trivial_compare_func(a, b);
-}
-
-static const struct hash_ops etc_hosts_item_ops = {
- .hash = etc_hosts_item_hash_func,
- .compare = etc_hosts_item_compare_func,
-};
-
-static int add_item(Manager *m, int family, const union in_addr_union *address, char **names) {
-
- EtcHostsItem key = {
- .family = family,
- .address = *address,
- };
- EtcHostsItem *item;
- char **n;
- int r;
-
- assert(m);
- assert(address);
-
- r = in_addr_is_null(family, address);
- if (r < 0)
- return r;
- if (r > 0)
- /* This is an 0.0.0.0 or :: item, which we assume means that we shall map the specified hostname to
- * nothing. */
- item = NULL;
- else {
- /* If this is a normal address, then, simply add entry mapping it to the specified names */
-
- item = set_get(m->etc_hosts_by_address, &key);
- if (item) {
- r = strv_extend_strv(&item->names, names, true);
- if (r < 0)
- return log_oom();
- } else {
-
- r = set_ensure_allocated(&m->etc_hosts_by_address, &etc_hosts_item_ops);
- if (r < 0)
- return log_oom();
-
- item = new0(EtcHostsItem, 1);
- if (!item)
- return log_oom();
-
- item->family = family;
- item->address = *address;
- item->names = names;
-
- r = set_put(m->etc_hosts_by_address, item);
- if (r < 0) {
- free(item);
- return log_oom();
- }
- }
- }
-
- STRV_FOREACH(n, names) {
- EtcHostsItemByName *bn;
-
- bn = hashmap_get(m->etc_hosts_by_name, *n);
- if (!bn) {
- r = hashmap_ensure_allocated(&m->etc_hosts_by_name, &dns_name_hash_ops);
- if (r < 0)
- return log_oom();
-
- bn = new0(EtcHostsItemByName, 1);
- if (!bn)
- return log_oom();
-
- bn->name = strdup(*n);
- if (!bn->name) {
- free(bn);
- return log_oom();
- }
-
- r = hashmap_put(m->etc_hosts_by_name, bn->name, bn);
- if (r < 0) {
- free(bn->name);
- free(bn);
- return log_oom();
- }
- }
-
- if (item) {
- if (!GREEDY_REALLOC(bn->items, bn->n_allocated, bn->n_items+1))
- return log_oom();
-
- bn->items[bn->n_items++] = item;
- }
- }
-
- return 0;
-}
-
-static int parse_line(Manager *m, unsigned nr, const char *line) {
- _cleanup_free_ char *address = NULL;
- _cleanup_strv_free_ char **names = NULL;
- union in_addr_union in;
- bool suppressed = false;
- int family, r;
-
- assert(m);
- assert(line);
-
- r = extract_first_word(&line, &address, NULL, EXTRACT_RELAX);
- if (r < 0)
- return log_error_errno(r, "Couldn't extract address, in line /etc/hosts:%u.", nr);
- if (r == 0) {
- log_error("Premature end of line, in line /etc/hosts:%u.", nr);
- return -EINVAL;
- }
-
- r = in_addr_from_string_auto(address, &family, &in);
- if (r < 0)
- return log_error_errno(r, "Address '%s' is invalid, in line /etc/hosts:%u.", address, nr);
-
- for (;;) {
- _cleanup_free_ char *name = NULL;
-
- r = extract_first_word(&line, &name, NULL, EXTRACT_RELAX);
- if (r < 0)
- return log_error_errno(r, "Couldn't extract host name, in line /etc/hosts:%u.", nr);
- if (r == 0)
- break;
-
- r = dns_name_is_valid(name);
- if (r <= 0)
- return log_error_errno(r, "Hostname %s is not valid, ignoring, in line /etc/hosts:%u.", name, nr);
-
- if (is_localhost(name)) {
- /* Suppress the "localhost" line that is often seen */
- suppressed = true;
- continue;
- }
-
- r = strv_push(&names, name);
- if (r < 0)
- return log_oom();
-
- name = NULL;
- }
-
- if (strv_isempty(names)) {
-
- if (suppressed)
- return 0;
-
- log_error("Line is missing any host names, in line /etc/hosts:%u.", nr);
- return -EINVAL;
- }
-
- /* Takes possession of the names strv */
- r = add_item(m, family, &in, names);
- if (r < 0)
- return r;
-
- names = NULL;
- return r;
-}
-
-int manager_etc_hosts_read(Manager *m) {
- _cleanup_fclose_ FILE *f = NULL;
- char line[LINE_MAX];
- struct stat st;
- usec_t ts;
- unsigned nr = 0;
- int r;
-
- assert_se(sd_event_now(m->event, clock_boottime_or_monotonic(), &ts) >= 0);
-
- /* See if we checked /etc/hosts recently already */
- if (m->etc_hosts_last != USEC_INFINITY && m->etc_hosts_last + ETC_HOSTS_RECHECK_USEC > ts)
- return 0;
-
- m->etc_hosts_last = ts;
-
- if (m->etc_hosts_mtime != USEC_INFINITY) {
- if (stat("/etc/hosts", &st) < 0) {
- if (errno == ENOENT) {
- r = 0;
- goto clear;
- }
-
- return log_error_errno(errno, "Failed to stat /etc/hosts: %m");
- }
-
- /* Did the mtime change? If not, there's no point in re-reading the file. */
- if (timespec_load(&st.st_mtim) == m->etc_hosts_mtime)
- return 0;
- }
-
- f = fopen("/etc/hosts", "re");
- if (!f) {
- if (errno == ENOENT) {
- r = 0;
- goto clear;
- }
-
- return log_error_errno(errno, "Failed to open /etc/hosts: %m");
- }
-
- /* Take the timestamp at the beginning of processing, so that any changes made later are read on the next
- * invocation */
- r = fstat(fileno(f), &st);
- if (r < 0)
- return log_error_errno(errno, "Failed to fstat() /etc/hosts: %m");
-
- manager_etc_hosts_flush(m);
-
- FOREACH_LINE(line, f, return log_error_errno(errno, "Failed to read /etc/hosts: %m")) {
- char *l;
-
- nr++;
-
- l = strstrip(line);
- if (isempty(l))
- continue;
- if (l[0] == '#')
- continue;
-
- r = parse_line(m, nr, l);
- if (r == -ENOMEM) /* On OOM we abandon the half-built-up structure. All other errors we ignore and proceed */
- goto clear;
- }
-
- m->etc_hosts_mtime = timespec_load(&st.st_mtim);
- m->etc_hosts_last = ts;
-
- return 1;
-
-clear:
- manager_etc_hosts_flush(m);
- return r;
-}
-
-int manager_etc_hosts_lookup(Manager *m, DnsQuestion* q, DnsAnswer **answer) {
- bool found_a = false, found_aaaa = false;
- EtcHostsItemByName *bn;
- EtcHostsItem k = {};
- DnsResourceKey *t;
- const char *name;
- unsigned i;
- int r;
-
- assert(m);
- assert(q);
- assert(answer);
-
- r = manager_etc_hosts_read(m);
- if (r < 0)
- return r;
-
- name = dns_question_first_name(q);
- if (!name)
- return 0;
-
- r = dns_name_address(name, &k.family, &k.address);
- if (r > 0) {
- EtcHostsItem *item;
- DnsResourceKey *found_ptr = NULL;
-
- item = set_get(m->etc_hosts_by_address, &k);
- if (!item)
- return 0;
-
- /* We have an address in /etc/hosts that matches the queried name. Let's return successful. Actual data
- * we'll only return if the request was for PTR. */
-
- DNS_QUESTION_FOREACH(t, q) {
- if (!IN_SET(t->type, DNS_TYPE_PTR, DNS_TYPE_ANY))
- continue;
- if (!IN_SET(t->class, DNS_CLASS_IN, DNS_CLASS_ANY))
- continue;
-
- r = dns_name_equal(dns_resource_key_name(t), name);
- if (r < 0)
- return r;
- if (r > 0) {
- found_ptr = t;
- break;
- }
- }
-
- if (found_ptr) {
- char **n;
-
- r = dns_answer_reserve(answer, strv_length(item->names));
- if (r < 0)
- return r;
-
- STRV_FOREACH(n, item->names) {
- _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
-
- rr = dns_resource_record_new(found_ptr);
- if (!rr)
- return -ENOMEM;
-
- rr->ptr.name = strdup(*n);
- if (!rr->ptr.name)
- return -ENOMEM;
-
- r = dns_answer_add(*answer, rr, 0, DNS_ANSWER_AUTHENTICATED);
- if (r < 0)
- return r;
- }
- }
-
- return 1;
- }
-
- bn = hashmap_get(m->etc_hosts_by_name, name);
- if (!bn)
- return 0;
-
- r = dns_answer_reserve(answer, bn->n_items);
- if (r < 0)
- return r;
-
- DNS_QUESTION_FOREACH(t, q) {
- if (!IN_SET(t->type, DNS_TYPE_A, DNS_TYPE_AAAA, DNS_TYPE_ANY))
- continue;
- if (!IN_SET(t->class, DNS_CLASS_IN, DNS_CLASS_ANY))
- continue;
-
- r = dns_name_equal(dns_resource_key_name(t), name);
- if (r < 0)
- return r;
- if (r == 0)
- continue;
-
- if (IN_SET(t->type, DNS_TYPE_A, DNS_TYPE_ANY))
- found_a = true;
- if (IN_SET(t->type, DNS_TYPE_AAAA, DNS_TYPE_ANY))
- found_aaaa = true;
-
- if (found_a && found_aaaa)
- break;
- }
-
- for (i = 0; i < bn->n_items; i++) {
- _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
-
- if ((found_a && bn->items[i]->family != AF_INET) &&
- (found_aaaa && bn->items[i]->family != AF_INET6))
- continue;
-
- r = dns_resource_record_new_address(&rr, bn->items[i]->family, &bn->items[i]->address, bn->name);
- if (r < 0)
- return r;
-
- r = dns_answer_add(*answer, rr, 0, DNS_ANSWER_AUTHENTICATED);
- if (r < 0)
- return r;
- }
-
- return 1;
-}
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