### Description
`dns_int_match_ip` is broken on 5.3.0 and above
### Troubleshooting
Reproduction
Try this dialplan:
```
if (dns_int_match_ip('dns.google', '8.8.8.8')) {
xlog("L_INFO", "OK dns-ip match with dns_int_match_ip");
} else {
xlog("L_ERR", "FAIL dns-ip match with dns_int_match_ip");
}
if (dns_int_match_ip('100.100.100.100', '8.8.8.8')) {
xlog("L_ERR", "FAIL dns_int_match_ip on 2 ip's");
} else {
xlog("L_INFO", "OK dns_int_match_ip on 2 ip's");
}
```
On 5.2 releases, both checks succeed. On 5.3 and up, both fail.
Debugging Data
I've traced down the problem to `str2ip`.
In 5.2, this is a `static inline` function defined in the header file
`resolve.h`. Therefore, the returned `ip` structure is allocated *once per
compilation unit* - ie. `ipops_mod.c` and `dns_cache.c` both have their own
versions of the variable.
Since fb75e90549a (5.3 and up) this function is defined in it's own compilation
unit (`resolve.c`) and therefore shared by all callers.
See:
https://stackoverflow.com/questions/185624/static-variables-in-an-inlined-function
Log Messages
n/a
SIP Traffic
n/a
### Possible Solutions
- Have `ki_dns_sys_match_ip` make a local copy of the return value of `str2ip`
- Move `str2ip` back to a header file
- Refactor `str2ip` to take a pointer to an output struct
### Additional Information
In 5.3, this is what happens:
```
# - ki_dns_int_match_ip will call str2ip on 8.8.8.8, filling the static variable
# - resolvehost will call dns_a_get_he, which calls str2ip on dns.google.com,
zeroing out the static variable
# - (dns_cache_do_request will call str2ip on dns.google.com, zeroing out the
static variable again)
# - resolvehost queries DNS
# - the resolved IP's will be compared to the zero'd out struct
dns_int_match_ip('dns.google', '8.8.8.8') == false
# - ki_dns_int_match_ip will call str2ip on 8.8.8.8, filling the static variable
# - resolvehost will call dns_a_get_he, which calls str2ip on 100.100.100.100,
overwriting the static variable
# - the static variable will be compared to itself
dns_int_match_ip('100.100.100.100', '8.8.8.8') == true
```
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