dnsinfo_internal.h [plain text]
#ifndef _S_DNSINFO_INTERNAL_H
#define _S_DNSINFO_INTERNAL_H
#include <Availability.h>
#include <TargetConditionals.h>
#include <sys/cdefs.h>
#include <SystemConfiguration/SystemConfiguration.h>
#include <SystemConfiguration/SCPrivate.h>
#include <arpa/inet.h>
#include <dnsinfo.h>
#include "dnsinfo_private.h"
#define DNS_CONFIG_BUF_MAX 1024*1024
__BEGIN_DECLS
#ifndef my_log
#define my_log(__level, __format, ...) SC_log(__level, __format, ## __VA_ARGS__)
#define MY_LOG_DEFINED_LOCALLY
#endif // !my_log
static __inline__ boolean_t
__dns_configuration_expand_add_list(void **padding, uint32_t *n_padding, uint32_t count, uint32_t size, void **list)
{
uint32_t need;
need = count * size;
if (need > *n_padding) {
return FALSE;
}
*list = (need == 0) ? NULL : *padding;
*padding += need;
*n_padding -= need;
return TRUE;
}
static __inline__ dns_resolver_t *
_dns_configuration_expand_resolver(_dns_resolver_buf_t *buf, uint32_t n_buf, void **padding, uint32_t *n_padding)
{
dns_attribute_t *attribute;
uint32_t n_attribute;
int32_t n_nameserver = 0;
int32_t n_search = 0;
int32_t n_sortaddr = 0;
void *ptr;
dns_resolver_t *resolver = (dns_resolver_t *)&buf->resolver;
if (n_buf < sizeof(_dns_resolver_buf_t)) {
goto error;
}
resolver->domain = NULL;
resolver->n_nameserver = ntohl(resolver->n_nameserver);
if (!__dns_configuration_expand_add_list(padding,
n_padding,
resolver->n_nameserver,
sizeof(DNS_PTR(struct sockaddr *, x)),
&ptr)) {
goto error;
}
resolver->nameserver = ptr;
resolver->port = ntohs(resolver->port);
resolver->n_search = ntohl(resolver->n_search);
if (!__dns_configuration_expand_add_list(padding,
n_padding,
resolver->n_search,
sizeof(DNS_PTR(char *, x)),
&ptr)) {
goto error;
}
resolver->search = ptr;
resolver->n_sortaddr = ntohl(resolver->n_sortaddr);
if (!__dns_configuration_expand_add_list(padding,
n_padding,
resolver->n_sortaddr,
sizeof(DNS_PTR(dns_sortaddr_t *, x)),
&ptr)) {
goto error;
}
resolver->sortaddr = ptr;
resolver->options = NULL;
resolver->timeout = ntohl(resolver->timeout);
resolver->search_order = ntohl(resolver->search_order);
resolver->if_index = ntohl(resolver->if_index);
resolver->service_identifier = ntohl(resolver->service_identifier);
resolver->flags = ntohl(resolver->flags);
resolver->reach_flags = ntohl(resolver->reach_flags);
n_attribute = n_buf - sizeof(_dns_resolver_buf_t);
attribute = (dns_attribute_t *)(void *)&buf->attribute[0];
if (n_attribute != ntohl(buf->n_attribute)) {
goto error;
}
while (n_attribute >= sizeof(dns_attribute_t)) {
uint32_t attribute_length = ntohl(attribute->length);
switch (ntohl(attribute->type)) {
case RESOLVER_ATTRIBUTE_DOMAIN :
resolver->domain = (char *)&attribute->attribute[0];
break;
case RESOLVER_ATTRIBUTE_ADDRESS :
if (resolver->nameserver == NULL) {
goto error;
}
resolver->nameserver[n_nameserver++] = (struct sockaddr *)&attribute->attribute[0];
break;
case RESOLVER_ATTRIBUTE_SEARCH :
if (resolver->search == NULL) {
goto error;
}
resolver->search[n_search++] = (char *)&attribute->attribute[0];
break;
case RESOLVER_ATTRIBUTE_SORTADDR :
if (resolver->sortaddr == NULL) {
goto error;
}
resolver->sortaddr[n_sortaddr++] = (dns_sortaddr_t *)(void *)&attribute->attribute[0];
break;
case RESOLVER_ATTRIBUTE_OPTIONS :
resolver->options = (char *)&attribute->attribute[0];
break;
case RESOLVER_ATTRIBUTE_CONFIGURATION_ID :
resolver->cid = (char *)&attribute->attribute[0];
break;
case RESOLVER_ATTRIBUTE_INTERFACE_NAME :
resolver->if_name = (char *)&attribute->attribute[0];
break;
default :
break;
}
attribute = (dns_attribute_t *)((void *)attribute + attribute_length);
n_attribute -= attribute_length;
}
if ((n_nameserver != resolver->n_nameserver) ||
(n_search != resolver->n_search ) ||
(n_sortaddr != resolver->n_sortaddr )) {
goto error;
}
return resolver;
error :
return NULL;
}
static __inline__ _dns_config_buf_t *
_dns_configuration_buffer_create(const void *dataRef, size_t dataLen)
{
uint8_t *buf = NULL;
size_t bufLen;
_dns_config_buf_t *config = (_dns_config_buf_t *)dataRef;
size_t configLen;
uint32_t n_attribute = ntohl(config->n_attribute);
uint32_t n_padding = ntohl(config->n_padding);
configLen = sizeof(_dns_config_buf_t) + n_attribute;
#ifdef DEBUG
assert(configLen == dataLen);
#else // DEBUG
if (configLen != dataLen) {
my_log(LOG_ERR, "DNS configuration: size error (%zu != %zu)", configLen, dataLen);
return NULL;
}
#endif // DEBUG
#ifdef DEBUG
assert(n_padding <= (DNS_CONFIG_BUF_MAX - dataLen));
#else // DEBUG
if (n_padding > (DNS_CONFIG_BUF_MAX - dataLen)) {
my_log(LOG_ERR, "DNS configuration: padding error (%u > %zu)",
n_padding,
(DNS_CONFIG_BUF_MAX - dataLen));
return NULL;
}
#endif // DEBUG
bufLen = dataLen + n_padding;
#ifdef DEBUG
assert(bufLen <= DNS_CONFIG_BUF_MAX);
#else // DEBUG
if (bufLen > DNS_CONFIG_BUF_MAX) {
my_log(LOG_ERR, "DNS configuration: length error (%zu > %u)",
bufLen,
DNS_CONFIG_BUF_MAX);
return NULL;
}
#endif // DEBUG
buf = malloc(bufLen);
bcopy((void *)dataRef, buf, dataLen);
bzero(&buf[dataLen], n_padding);
return (_dns_config_buf_t *)(void *)buf;
}
static __inline__ void
_dns_configuration_buffer_free(_dns_config_buf_t **buf)
{
_dns_config_buf_t *config = (_dns_config_buf_t *)*buf;
free(config);
*buf = NULL;
return;
}
static __inline__ dns_config_t *
_dns_configuration_buffer_expand(_dns_config_buf_t *buf)
{
dns_attribute_t *attribute;
dns_config_t *config = (dns_config_t *)buf;
uint32_t n_attribute;
uint32_t n_padding;
int32_t n_resolver = 0;
int32_t n_scoped_resolver = 0;
int32_t n_service_specific_resolver = 0;
void *padding;
void *ptr;
n_attribute = ntohl(buf->n_attribute); n_padding = ntohl(buf->n_padding);
padding = &buf->attribute[n_attribute];
config->n_resolver = ntohl(config->n_resolver);
if (!__dns_configuration_expand_add_list(&padding,
&n_padding,
config->n_resolver,
sizeof(DNS_PTR(dns_resolver_t *, x)),
&ptr)) {
goto error;
}
config->resolver = ptr;
config->n_scoped_resolver = ntohl(config->n_scoped_resolver);
if (!__dns_configuration_expand_add_list(&padding,
&n_padding,
config->n_scoped_resolver,
sizeof(DNS_PTR(dns_resolver_t *, x)),
&ptr)) {
goto error;
}
config->scoped_resolver = ptr;
config->n_service_specific_resolver = ntohl(config->n_service_specific_resolver);
if (!__dns_configuration_expand_add_list(&padding,
&n_padding,
config->n_service_specific_resolver,
sizeof(DNS_PTR(dns_resolver_t *, x)),
&ptr)) {
goto error;
}
config->service_specific_resolver = ptr;
attribute = (dns_attribute_t *)(void *)&buf->attribute[0];
while (n_attribute >= sizeof(dns_attribute_t)) {
uint32_t attribute_length = ntohl(attribute->length);
uint32_t attribute_type = ntohl(attribute->type);
switch (attribute_type) {
case CONFIG_ATTRIBUTE_RESOLVER :
case CONFIG_ATTRIBUTE_SCOPED_RESOLVER :
case CONFIG_ATTRIBUTE_SERVICE_SPECIFIC_RESOLVER : {
dns_resolver_t *resolver;
resolver = _dns_configuration_expand_resolver((_dns_resolver_buf_t *)(void *)&attribute->attribute[0],
attribute_length - sizeof(dns_attribute_t),
&padding,
&n_padding);
if (resolver == NULL) {
goto error;
}
if (attribute_type == CONFIG_ATTRIBUTE_RESOLVER) {
if (config->resolver == NULL) {
goto error;
}
config->resolver[n_resolver++] = resolver;
} else if (attribute_type == CONFIG_ATTRIBUTE_SCOPED_RESOLVER) {
if (config->scoped_resolver == NULL) {
goto error;
}
config->scoped_resolver[n_scoped_resolver++] = resolver;
} else if (attribute_type == CONFIG_ATTRIBUTE_SERVICE_SPECIFIC_RESOLVER) {
if (config->service_specific_resolver == NULL) {
goto error;
}
config->service_specific_resolver[n_service_specific_resolver++] = resolver;
}
break;
}
default :
break;
}
attribute = (dns_attribute_t *)((void *)attribute + attribute_length);
n_attribute -= attribute_length;
}
if (n_resolver != config->n_resolver) {
goto error;
}
if (n_scoped_resolver != config->n_scoped_resolver) {
goto error;
}
if (n_service_specific_resolver != config->n_service_specific_resolver) {
goto error;
}
return config;
error :
return NULL;
}
#ifdef MY_LOG_DEFINED_LOCALLY
#undef my_log
#undef MY_LOG_DEFINED_LOCALLY
#endif // MY_LOG_DEFINED_LOCALLY
__END_DECLS
#endif