int cache;
grub_uint16_t id;
int dns_err;
- const char *name;
+ char *name;
};
static int
-check_name (const grub_uint8_t *name_at, const grub_uint8_t *head,
- const grub_uint8_t *tail, const char *check_with)
+check_name_real (const grub_uint8_t *name_at, const grub_uint8_t *head,
+ const grub_uint8_t *tail, const char *check_with,
+ int *length, char *set)
{
const char *readable_ptr = check_with;
const grub_uint8_t *ptr;
+ char *optr = set;
int bytes_processed = 0;
+ if (length)
+ *length = 0;
for (ptr = name_at; ptr < tail && bytes_processed < tail - head + 2; )
{
/* End marker. */
if (!*ptr)
- return (*readable_ptr == 0);
+ {
+ if (length && *length)
+ (*length)--;
+ if (optr && optr != set)
+ optr--;
+ if (optr)
+ *optr = 0;
+ return !readable_ptr || (*readable_ptr == 0);
+ }
if (*ptr & 0xc0)
{
bytes_processed += 2;
ptr = head + (((ptr[0] & 0x3f) << 8) | ptr[1]);
continue;
}
- if (grub_memcmp (ptr + 1, readable_ptr, *ptr) != 0)
+ if (readable_ptr && grub_memcmp (ptr + 1, readable_ptr, *ptr) != 0)
return 0;
if (grub_memchr (ptr + 1, 0, *ptr)
|| grub_memchr (ptr + 1, '.', *ptr))
return 0;
- if (readable_ptr[*ptr] != '.' && readable_ptr[*ptr] != 0)
+ if (readable_ptr)
+ readable_ptr += *ptr;
+ if (readable_ptr && *readable_ptr != '.' && *readable_ptr != 0)
return 0;
bytes_processed += *ptr + 1;
- readable_ptr += *ptr;
- if (*readable_ptr)
+ if (length)
+ *length += *ptr + 1;
+ if (optr)
+ {
+ grub_memcpy (optr, ptr + 1, *ptr);
+ optr += *ptr;
+ }
+ if (optr)
+ *optr++ = '.';
+ if (readable_ptr && *readable_ptr)
readable_ptr++;
ptr += *ptr + 1;
}
return 0;
}
+static int
+check_name (const grub_uint8_t *name_at, const grub_uint8_t *head,
+ const grub_uint8_t *tail, const char *check_with)
+{
+ return check_name_real (name_at, head, tail, check_with, NULL, NULL);
+}
+
+static char *
+get_name (const grub_uint8_t *name_at, const grub_uint8_t *head,
+ const grub_uint8_t *tail)
+{
+ int length;
+ char *ret;
+
+ if (!check_name_real (name_at, head, tail, NULL, &length, NULL))
+ return NULL;
+ ret = grub_malloc (length + 1);
+ if (!ret)
+ return NULL;
+ if (!check_name_real (name_at, head, tail, NULL, NULL, ret))
+ {
+ grub_free (ret);
+ return NULL;
+ }
+ return ret;
+}
+
+enum
+ {
+ DNS_CLASS_A = 1,
+ DNS_CLASS_CNAME = 5,
+ DNS_CLASS_AAAA = 28
+ };
+
static grub_err_t
recv_hook (grub_net_udp_socket_t sock __attribute__ ((unused)),
struct grub_net_buff *nb,
struct dns_header *head;
struct recv_data *data = data_;
int i, j;
- grub_uint8_t *ptr;
+ grub_uint8_t *ptr, *reparse_ptr;
+ int redirect_cnt = 0;
+ char *redirect_save = NULL;
head = (struct dns_header *) nb->data;
ptr = (grub_uint8_t *) (head + 1);
grub_netbuff_free (nb);
return GRUB_ERR_NONE;
}
- for (i = 0; i < grub_cpu_to_be16 (head->ancount); i++)
+ reparse_ptr = ptr;
+ reparse:
+ for (i = 0, ptr = reparse_ptr; i < grub_cpu_to_be16 (head->ancount); i++)
{
int ignored = 0;
- int is_ipv6 = 0;
+ grub_uint8_t class;
grub_uint32_t ttl = 0;
grub_uint16_t length;
if (ptr >= nb->tail)
}
if (*ptr++ != 0)
ignored = 1;
- if (*ptr != 1 && *ptr != 28)
- ignored = 1;
- if (*ptr == 28)
- is_ipv6 = 1;
- ptr++;
+ class = *ptr++;
if (*ptr++ != 0)
ignored = 1;
if (*ptr++ != 1)
grub_netbuff_free (nb);
return GRUB_ERR_NONE;
}
- if (!ignored && !is_ipv6 && length == 4)
- {
- (*data->addresses)[*data->naddresses].type
- = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4;
- grub_memcpy (&(*data->addresses)[*data->naddresses].ipv4,
- ptr, 4);
- (*data->naddresses)++;
- }
- if (!ignored && is_ipv6 && length == 16)
- {
- (*data->addresses)[*data->naddresses].type
- = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV6;
- grub_memcpy (&(*data->addresses)[*data->naddresses].ipv6,
+ if (!ignored)
+ switch (class)
+ {
+ case DNS_CLASS_A:
+ if (length != 4)
+ break;
+ (*data->addresses)[*data->naddresses].type
+ = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV4;
+ grub_memcpy (&(*data->addresses)[*data->naddresses].ipv4,
+ ptr, 4);
+ (*data->naddresses)++;
+ break;
+ case DNS_CLASS_AAAA:
+ if (length != 16)
+ break;
+ (*data->addresses)[*data->naddresses].type
+ = GRUB_NET_NETWORK_LEVEL_PROTOCOL_IPV6;
+ grub_memcpy (&(*data->addresses)[*data->naddresses].ipv6,
ptr, 16);
- (*data->naddresses)++;
+ (*data->naddresses)++;
+ break;
+ case DNS_CLASS_CNAME:
+ if (!(redirect_cnt & (redirect_cnt - 1)))
+ {
+ grub_free (redirect_save);
+ redirect_save = data->name;
+ }
+ else
+ grub_free (data->name);
+ redirect_cnt++;
+ data->name = get_name (ptr, nb->data, nb->tail);
+ if (!data->name)
+ {
+ data->dns_err = 1;
+ grub_errno = 0;
+ return GRUB_ERR_NONE;
+ }
+ grub_dprintf ("dns", "CNAME %s\n", data->name);
+ if (grub_strcmp (redirect_save, data->name) == 0)
+ {
+ data->dns_err = 1;
+ grub_free (redirect_save);
+ return GRUB_ERR_NONE;
+ }
+ goto reparse;
}
ptr += length;
}
grub_netbuff_free (nb);
+ grub_free (redirect_save);
return GRUB_ERR_NONE;
}
static grub_uint16_t id = 1;
grub_err_t err = GRUB_ERR_NONE;
struct recv_data data = {naddresses, addresses, cache,
- grub_cpu_to_be16 (id++), 0, name};
+ grub_cpu_to_be16 (id++), 0, 0};
grub_uint8_t *nbd;
int have_server = 0;
+ data.name = grub_strdup (name);
+ if (!data.name)
+ return grub_errno;
+
*naddresses = 0;
/* if (cache && cache_lookup (name, servers, n_servers, addresses))
return GRUB_ERR_NONE;*/
+ grub_strlen (name) + 2 + 4
+ 2 + 4);
if (!nb)
- return grub_errno;
+ {
+ grub_free (data.name);
+ return grub_errno;
+ }
grub_netbuff_reserve (nb, GRUB_NET_OUR_MAX_IP_HEADER_SIZE
+ GRUB_NET_MAX_LINK_HEADER_SIZE
+ GRUB_NET_UDP_HEADER_SIZE);
if (!dot)
dot = iptr + grub_strlen (iptr);
if ((dot - iptr) >= 64)
- return grub_error (GRUB_ERR_BAD_ARGUMENT,
- "domain component is too long");
+ {
+ grub_free (data.name);
+ return grub_error (GRUB_ERR_BAD_ARGUMENT,
+ "domain component is too long");
+ }
*optr = (dot - iptr);
optr++;
grub_memcpy (optr, iptr, dot - iptr);
grub_net_poll_cards (200);
}
out:
+ grub_free (data.name);
grub_netbuff_free (nb);
for (j = 0; j < send_servers; j++)
grub_net_udp_close (sockets[j]);
+
if (*data.naddresses)
return GRUB_ERR_NONE;
if (data.dns_err)
projects / thirdparty / grub.git / commitdiff
