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Diffstat (limited to 'src/resolve/resolved-resolv-conf.c')
-rw-r--r--src/resolve/resolved-resolv-conf.c276
1 files changed, 0 insertions, 276 deletions
diff --git a/src/resolve/resolved-resolv-conf.c b/src/resolve/resolved-resolv-conf.c
deleted file mode 100644
index 801014caf5..0000000000
--- a/src/resolve/resolved-resolv-conf.c
+++ /dev/null
@@ -1,276 +0,0 @@
-/***
- This file is part of systemd.
-
- Copyright 2014 Tom Gundersen <teg@jklm.no>
-
- 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 <resolv.h>
-
-#include "alloc-util.h"
-#include "dns-domain.h"
-#include "fd-util.h"
-#include "fileio-label.h"
-#include "fileio.h"
-#include "ordered-set.h"
-#include "resolved-conf.h"
-#include "resolved-resolv-conf.h"
-#include "string-util.h"
-#include "strv.h"
-
-int manager_read_resolv_conf(Manager *m) {
- _cleanup_fclose_ FILE *f = NULL;
- struct stat st, own;
- char line[LINE_MAX];
- usec_t t;
- int r;
-
- assert(m);
-
- /* Reads the system /etc/resolv.conf, if it exists and is not
- * symlinked to our own resolv.conf instance */
-
- if (!m->read_resolv_conf)
- return 0;
-
- r = stat("/etc/resolv.conf", &st);
- if (r < 0) {
- if (errno == ENOENT)
- return 0;
-
- r = log_warning_errno(errno, "Failed to stat /etc/resolv.conf: %m");
- goto clear;
- }
-
- /* Have we already seen the file? */
- t = timespec_load(&st.st_mtim);
- if (t == m->resolv_conf_mtime)
- return 0;
-
- /* Is it symlinked to our own file? */
- if (stat("/run/systemd/resolve/resolv.conf", &own) >= 0 &&
- st.st_dev == own.st_dev &&
- st.st_ino == own.st_ino)
- return 0;
-
- f = fopen("/etc/resolv.conf", "re");
- if (!f) {
- if (errno == ENOENT)
- return 0;
-
- r = log_warning_errno(errno, "Failed to open /etc/resolv.conf: %m");
- goto clear;
- }
-
- if (fstat(fileno(f), &st) < 0) {
- r = log_error_errno(errno, "Failed to stat open file: %m");
- goto clear;
- }
-
- dns_server_mark_all(m->dns_servers);
- dns_search_domain_mark_all(m->search_domains);
-
- FOREACH_LINE(line, f, r = -errno; goto clear) {
- const char *a;
- char *l;
-
- l = strstrip(line);
- if (*l == '#' || *l == ';')
- continue;
-
- a = first_word(l, "nameserver");
- if (a) {
- r = manager_parse_dns_server_string_and_warn(m, DNS_SERVER_SYSTEM, a);
- if (r < 0)
- log_warning_errno(r, "Failed to parse DNS server address '%s', ignoring.", a);
-
- continue;
- }
-
- a = first_word(l, "domain");
- if (!a) /* We treat "domain" lines, and "search" lines as equivalent, and add both to our list. */
- a = first_word(l, "search");
- if (a) {
- r = manager_parse_search_domains_and_warn(m, a);
- if (r < 0)
- log_warning_errno(r, "Failed to parse search domain string '%s', ignoring.", a);
- }
- }
-
- m->resolv_conf_mtime = t;
-
- /* Flush out all servers and search domains that are still
- * marked. Those are then ones that didn't appear in the new
- * /etc/resolv.conf */
- dns_server_unlink_marked(m->dns_servers);
- dns_search_domain_unlink_marked(m->search_domains);
-
- /* Whenever /etc/resolv.conf changes, start using the first
- * DNS server of it. This is useful to deal with broken
- * network managing implementations (like NetworkManager),
- * that when connecting to a VPN place both the VPN DNS
- * servers and the local ones in /etc/resolv.conf. Without
- * resetting the DNS server to use back to the first entry we
- * will continue to use the local one thus being unable to
- * resolve VPN domains. */
- manager_set_dns_server(m, m->dns_servers);
-
- /* Unconditionally flush the cache when /etc/resolv.conf is
- * modified, even if the data it contained was completely
- * identical to the previous version we used. We do this
- * because altering /etc/resolv.conf is typically done when
- * the network configuration changes, and that should be
- * enough to flush the global unicast DNS cache. */
- if (m->unicast_scope)
- dns_cache_flush(&m->unicast_scope->cache);
-
- return 0;
-
-clear:
- dns_server_unlink_all(m->dns_servers);
- dns_search_domain_unlink_all(m->search_domains);
- return r;
-}
-
-static void write_resolv_conf_server(DnsServer *s, FILE *f, unsigned *count) {
- assert(s);
- assert(f);
- assert(count);
-
- if (!dns_server_string(s)) {
- log_warning("Our of memory, or invalid DNS address. Ignoring server.");
- return;
- }
-
- /* Check if the DNS server is limited to particular domains;
- * resolv.conf does not have a syntax to express that, so it must not
- * appear as a global name server to avoid routing unrelated domains to
- * it (which is a privacy violation, will most probably fail anyway,
- * and adds unnecessary load) */
- if (dns_server_limited_domains(s)) {
- log_debug("DNS server %s has route-only domains, not using as global name server", dns_server_string(s));
- return;
- }
-
- if (*count == MAXNS)
- fputs("# Too many DNS servers configured, the following entries may be ignored.\n", f);
- (*count)++;
-
- fprintf(f, "nameserver %s\n", dns_server_string(s));
-}
-
-static void write_resolv_conf_search(
- OrderedSet *domains,
- FILE *f) {
- unsigned length = 0, count = 0;
- Iterator i;
- char *domain;
-
- assert(domains);
- assert(f);
-
- fputs("search", f);
-
- ORDERED_SET_FOREACH(domain, domains, i) {
- if (++count > MAXDNSRCH) {
- fputs("\n# Too many search domains configured, remaining ones ignored.", f);
- break;
- }
- length += strlen(domain) + 1;
- if (length > 256) {
- fputs("\n# Total length of all search domains is too long, remaining ones ignored.", f);
- break;
- }
- fputc(' ', f);
- fputs(domain, f);
- }
-
- fputs("\n", f);
-}
-
-static int write_resolv_conf_contents(FILE *f, OrderedSet *dns, OrderedSet *domains) {
- Iterator i;
-
- fputs("# This file is managed by systemd-resolved(8). Do not edit.\n#\n"
- "# This is a dynamic resolv.conf file for connecting local clients directly to\n"
- "# all known DNS servers.\n#\n"
- "# Third party programs must not access this file directly, but only through the\n"
- "# symlink at /etc/resolv.conf. To manage resolv.conf(5) in a different way,\n"
- "# replace this symlink by a static file or a different symlink.\n#\n"
- "# See systemd-resolved.service(8) for details about the supported modes of\n"
- "# operation for /etc/resolv.conf.\n\n", f);
-
- if (ordered_set_isempty(dns))
- fputs("# No DNS servers known.\n", f);
- else {
- unsigned count = 0;
- DnsServer *s;
-
- ORDERED_SET_FOREACH(s, dns, i)
- write_resolv_conf_server(s, f, &count);
- }
-
- if (!ordered_set_isempty(domains))
- write_resolv_conf_search(domains, f);
-
- return fflush_and_check(f);
-}
-
-int manager_write_resolv_conf(Manager *m) {
-
- _cleanup_ordered_set_free_ OrderedSet *dns = NULL, *domains = NULL;
- _cleanup_free_ char *temp_path = NULL;
- _cleanup_fclose_ FILE *f = NULL;
- int r;
-
- assert(m);
-
- /* Read the system /etc/resolv.conf first */
- (void) manager_read_resolv_conf(m);
-
- /* Add the full list to a set, to filter out duplicates */
- r = manager_compile_dns_servers(m, &dns);
- if (r < 0)
- return log_warning_errno(r, "Failed to compile list of DNS servers: %m");
-
- r = manager_compile_search_domains(m, &domains, false);
- if (r < 0)
- return log_warning_errno(r, "Failed to compile list of search domains: %m");
-
- r = fopen_temporary_label(PRIVATE_RESOLV_CONF, PRIVATE_RESOLV_CONF, &f, &temp_path);
- if (r < 0)
- return log_warning_errno(r, "Failed to open private resolv.conf file for writing: %m");
-
- (void) fchmod(fileno(f), 0644);
-
- r = write_resolv_conf_contents(f, dns, domains);
- if (r < 0) {
- log_error_errno(r, "Failed to write private resolv.conf contents: %m");
- goto fail;
- }
-
- if (rename(temp_path, PRIVATE_RESOLV_CONF) < 0) {
- r = log_error_errno(errno, "Failed to move private resolv.conf file into place: %m");
- goto fail;
- }
-
- return 0;
-
-fail:
- (void) unlink(PRIVATE_RESOLV_CONF);
- (void) unlink(temp_path);
-
- return r;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 10:34:38 +0000