mirrors/haproxy
1
0
Fork 0
mirror of https://git.haproxy.org/git/haproxy.git/ synced 2025-08-07 23:56:57 +02:00
Code Issues Projects Releases Wiki Activity

MINOR: dns: Implement parse-resolv-conf directive

Browse Source 
This introduces a new directive for the `resolvers` section:
`parse-resolv-conf`. When present, it will attempt to add any
nameservers in `/etc/resolv.conf` to the list of nameservers
for the current `resolvers` section.

[Mailing list thread][1].

[1]: https://www.mail-archive.com/haproxy@formilux.org/msg29600.html
This commit is contained in:
Ben Draut 2018-05-29 15:40:08 -06:00 committed by Willy Tarreau
parent 082627af77
commit 44e609bfa5
2 changed files with 120 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
doc/configuration.txt
View File

@ -12042,6 +12042,11 @@ nameserver <id> <ip>:<port>
<ip> : IP address of the server
<port> : port where the DNS service actually runs
parse-resolv-conf
Adds all nameservers found in /etc/resolv.conf to this resolvers nameservers
list. Ordered as if each nameserver in /etc/resolv.conf was individually
placed in the resolvers section in place of this directive.
hold <status> <period>
Defines <period> during which the last name resolution should be kept based
on last resolution <status>
@ -12085,6 +12090,7 @@ timeout <event> <time>
resolvers mydns
nameserver dns1 10.0.0.1:53
nameserver dns2 10.0.0.2:53
parse-resolv-conf
resolve_retries 3
timeout resolve 1s
timeout retry 1s

115
src/cfgparse.c
View File

@ -2256,7 +2256,7 @@ int cfg_parse_resolvers(const char *file, int linenum, char **args, int kwm)
/* Error if two resolvers owns the same name */
if (strcmp(newnameserver->id, args[1]) == 0) {
ha_alert("Parsing [%s:%d]: nameserver '%s' has same name as another nameserver (declared at %s:%d).\n",
file, linenum, args[1], curr_resolvers->conf.file, curr_resolvers->conf.line);
file, linenum, args[1], newnameserver->conf.file, newnameserver->conf.line);
err_code |= ERR_ALERT | ERR_FATAL;
}
}
@ -2305,6 +2305,119 @@ int cfg_parse_resolvers(const char *file, int linenum, char **args, int kwm)
newnameserver->addr = *sk;
}
else if (strcmp(args[0], "parse-resolv-conf") == 0) {
const char *whitespace = "\r\n\t ";
char *resolv_line = NULL;
int resolv_linenum = 0;
FILE *f = NULL;
char *address = NULL;
struct sockaddr_storage *sk = NULL;
struct protocol *proto;
int duplicate_name = 0;
if ((resolv_line = malloc(sizeof(*resolv_line) * LINESIZE)) == NULL) {
ha_alert("parsing [%s:%d] : out of memory.\n",
file, linenum);
err_code |= ERR_ALERT | ERR_FATAL;
goto resolv_out;
}
if ((f = fopen("/etc/resolv.conf", "r")) == NULL) {
ha_alert("parsing [%s:%d] : failed to open /etc/resolv.conf.\n",
file, linenum);
err_code |= ERR_ALERT | ERR_FATAL;
goto resolv_out;
}
sk = calloc(1, sizeof(*sk));
if (sk == NULL) {
ha_alert("parsing [/etc/resolv.conf:%d] : out of memory.\n",
resolv_linenum);
err_code |= ERR_ALERT | ERR_FATAL;
goto resolv_out;
}
while (fgets(resolv_line, LINESIZE, f) != NULL) {
resolv_linenum++;
if (strncmp(resolv_line, "nameserver", 10) != 0)
continue;
address = strtok(resolv_line + 10, whitespace);
if (address == resolv_line + 10)
continue;
if (address == NULL) {
ha_warning("parsing [/etc/resolv.conf:%d] : nameserver line is missing address.\n",
resolv_linenum);
err_code |= ERR_WARN;
continue;
}
duplicate_name = 0;
list_for_each_entry(newnameserver, &curr_resolvers->nameservers, list) {
if (strcmp(newnameserver->id, address) == 0) {
ha_warning("Parsing [/etc/resolv.conf:%d] : generated name for /etc/resolv.conf nameserver '%s' conflicts with another nameserver (declared at %s:%d), it appears to be a duplicate and will be excluded.\n",
resolv_linenum, address, newnameserver->conf.file, newnameserver->conf.line);
err_code |= ERR_WARN;
duplicate_name = 1;
}
}
if (duplicate_name)
continue;
memset(sk, 0, sizeof(*sk));
sk = str2ip2(address, sk, 1);
if (!sk) {
ha_warning("parsing [/etc/resolv.conf:%d] : address '%s' could not be recognized, namerserver will be excluded.\n",
resolv_linenum, address);
err_code |= ERR_WARN;
continue;
}
set_host_port(sk, 53);
proto = protocol_by_family(sk->ss_family);
if (!proto || !proto->connect) {
ha_warning("parsing [/etc/resolv.conf:%d] : '%s' : connect() not supported for this address family.\n",
resolv_linenum, address);
err_code |= ERR_WARN;
continue;
}
if ((newnameserver = calloc(1, sizeof(*newnameserver))) == NULL) {
ha_alert("parsing [/etc/resolv.conf:%d] : out of memory.\n", resolv_linenum);
err_code |= ERR_ALERT | ERR_FATAL;
goto resolv_out;
}
newnameserver->conf.file = strdup("/etc/resolv.conf");
if (newnameserver->conf.file == NULL) {
ha_alert("parsing [/etc/resolv.conf:%d] : out of memory.\n", resolv_linenum);
err_code |= ERR_ALERT | ERR_FATAL;
goto resolv_out;
}
newnameserver->id = strdup(address);
if (newnameserver->id == NULL) {
ha_alert("parsing [/etc/resolv.conf:%d] : out of memory.\n", resolv_linenum);
err_code |= ERR_ALERT | ERR_FATAL;
goto resolv_out;
}
newnameserver->resolvers = curr_resolvers;
newnameserver->conf.line = resolv_linenum;
newnameserver->addr = *sk;
LIST_ADDQ(&curr_resolvers->nameservers, &newnameserver->list);
}
resolv_out:
free(sk);
free(resolv_line);
if (f != NULL)
fclose(f);
}
else if (strcmp(args[0], "hold") == 0) { /* hold periods */
const char *res;
unsigned int time;