[forward-port] Implement an option, VirtualAddrMask, to set which addresses get handed out in response to mapaddress requests. Needs testing and docs!

svn:r6398
This commit is contained in:
Nick Mathewson 2006-04-18 03:36:28 +00:00
parent 6ebd886511
commit 0df40a393b
3 changed files with 80 additions and 13 deletions

View File

@ -238,6 +238,7 @@ static config_var_t _option_vars[] = {
VAR("User", STRING, User, NULL),
VAR("V1AuthoritativeDirectory",BOOL, V1AuthoritativeDir, "0"),
VAR("VersioningAuthoritativeDirectory",BOOL,VersioningAuthoritativeDir, "0"),
VAR("VirtualAddrNetwork", STRING, VirtualAddrNetwork, "127.192.0.0/10"),
VAR("__LeaveStreamsUnattached", BOOL,LeaveStreamsUnattached, "0"),
{ NULL, CONFIG_TYPE_OBSOLETE, 0, NULL }
};
@ -677,6 +678,7 @@ options_act(or_options_t *old_options)
size_t len;
or_options_t *options = get_options();
int running_tor = options->command == CMD_RUN_TOR;
const char *msg;
clear_trusted_dir_servers();
if (options->DirServers) {
@ -745,6 +747,7 @@ options_act(or_options_t *old_options)
/* Register addressmap directives */
config_register_addressmaps(options);
parse_virtual_addr_network(options->VirtualAddrNetwork, 0, &msg);
/* Update address policies. */
policies_parse_from_options(options);
@ -2404,6 +2407,9 @@ options_validate(or_options_t *old_options, or_options_t *options,
if (rend_config_services(options, 1) < 0)
REJECT("Failed to configure rendezvous options. See logs for details.");
if (parse_virtual_addr_network(options->VirtualAddrNetwork, 1, msg)<0)
return -1;
return 0;
#undef REJECT
#undef COMPLAIN

View File

@ -750,15 +750,65 @@ client_dns_set_addressmap(const char *address, uint32_t val,
time(NULL) + ttl);
}
/* Currently, we hand out 127.192.0.1 through 127.254.254.254.
/* By default, we hand out 127.192.0.1 through 127.254.254.254.
* These addresses should map to localhost, so even if the
* application accidentally tried to connect to them directly (not
* via Tor), it wouldn't get too far astray.
*
* Eventually, we should probably make this configurable.
*/
#define MIN_UNUSED_IPV4 0x7fc00001u
#define MAX_UNUSED_IPV4 0x7ffefefeu
static uint32_t virtual_addr_network = 0x7fc00000u;
static uint32_t virtual_addr_netmask = 0xffc00000u;
static int virtual_addr_netmask_bits = 10;
static uint32_t next_virtual_addr = 0x7fc00000u;
/** Read a netmask of the form 127.192.0.0/10 from "val", and check whether
* it's a valid set of virtual addresses to hand out in response to MAPADDRESS
* requests. Return 0 on success; set *msg and return -1 on failure. If
* validate_only is false, sets the actual virtual address range to the parsed
* value. */
int
parse_virtual_addr_network(const char *val, int validate_only,
const char **msg)
{
uint32_t addr, mask;
uint16_t port_min, port_max;
int bits;
if (parse_addr_and_port_range(val, &addr, &mask, &port_min, &port_max)) {
*msg = "Error parsing VirtualAddressNetwork";
return -1;
}
if (port_min != 1 || port_max != 65535) {
*msg = "Can't specify ports on VirtualAddressNetwork";
return -1;
}
bits = addr_mask_get_bits(mask);
if (bits < 0) {
*msg = "VirtualAddressNetwork must have a mask that can be expressed "
"as a prefix";
return -1;
}
if (bits > 16) {
*msg = "VirtualAddressNetwork expects a class B network or larger";
return -1;
}
if (validate_only)
return 0;
virtual_addr_network = addr & mask;
virtual_addr_netmask = mask;
virtual_addr_netmask_bits = bits;
if ((next_virtual_addr & mask) != addr)
next_virtual_addr = addr;
return 0;
}
/**
* Return true iff <b>addr</b> is likely to have been returned by
@ -773,7 +823,7 @@ address_is_in_virtual_range(const char *address)
return 1;
} else if (tor_inet_aton(address, &in)) {
uint32_t addr = ntohl(in.s_addr);
if (addr >= MIN_UNUSED_IPV4 && addr <= MAX_UNUSED_IPV4)
if ((addr & virtual_addr_netmask) == virtual_addr_network)
return 1;
}
return 0;
@ -787,7 +837,6 @@ static char *
addressmap_get_virtual_address(int type)
{
char buf[64];
static uint32_t next_ipv4 = MIN_UNUSED_IPV4;
struct in_addr in;
if (type == RESOLVED_TYPE_HOSTNAME) {
@ -799,19 +848,26 @@ addressmap_get_virtual_address(int type)
} while (strmap_get(addressmap, buf));
return tor_strdup(buf);
} else if (type == RESOLVED_TYPE_IPV4) {
while (1) {
uint32_t available = 1u << virtual_addr_netmask_bits;
while (available) {
/* Don't hand out any .0 or .255 address. */
while ((next_ipv4 & 0xff) == 0 ||
(next_ipv4 & 0xff) == 0xff)
++next_ipv4;
in.s_addr = htonl(next_ipv4);
while ((next_virtual_addr & 0xff) == 0 ||
(next_virtual_addr & 0xff) == 0xff) {
++next_virtual_addr;
}
in.s_addr = htonl(next_virtual_addr);
tor_inet_ntoa(&in, buf, sizeof(buf));
if (!strmap_get(addressmap, buf))
break;
++next_ipv4;
if (next_ipv4 > MAX_UNUSED_IPV4)
next_ipv4 = MIN_UNUSED_IPV4;
++next_virtual_addr;
--available;
if (! --available) {
log_warn(LD_CONFIG, "Ran out of virtual addresses!");
return NULL;
}
if ((next_virtual_addr & virtual_addr_netmask) != virtual_addr_network)
next_virtual_addr = virtual_addr_network;
}
return tor_strdup(buf);
} else {

View File

@ -1383,6 +1383,9 @@ typedef struct {
* of our PK time by sending CREATE_FAST cells? */
addr_policy_t *reachable_addr_policy; /**< Parsed from ReachableAddresses */
char *VirtualAddrNetwork; /**< Address and mask to hand out for virtual
* MAPADDRESS requests. */
} or_options_t;
/** Persistent state for an onion router, as saved to disk. */
@ -1725,6 +1728,8 @@ void addressmap_rewrite(char *address, size_t maxlen);
int addressmap_already_mapped(const char *address);
void addressmap_register(const char *address, char *new_address,
time_t expires);
int parse_virtual_addr_network(const char *val, int validate_only,
const char **msg);
int client_dns_incr_failures(const char *address);
void client_dns_clear_failures(const char *address);
void client_dns_set_addressmap(const char *address, uint32_t val,