From: Antonio Quartulli <anto...@openvpn.net>
With this change a server is allowed to allocate an
IPv6-only pool. This is required to make it capable
of managing an IPv6-only tunnel.
Trac: #208
Signed-off-by: Antonio Quartulli <anto...@openvpn.net>
---
Changes from v3:
- properly compute pool size taking into account the actual base address
src/openvpn/multi.c | 10 ++-
src/openvpn/pool.c | 181 ++++++++++++++++++++++++++++++++------------
src/openvpn/pool.h | 8 +-
3 files changed, 146 insertions(+), 53 deletions(-)
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 7f61350d..2fbbe9ec 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -388,7 +388,8 @@ multi_init(struct multi_context *m, struct context *t, bool
tcp_mode, int thread
* differently based on whether a tun or tap style
* tunnel.
*/
- if (t->options.ifconfig_pool_defined)
+ if (t->options.ifconfig_pool_defined
+ || t->options.ifconfig_ipv6_pool_defined)
{
int pool_type = IFCONFIG_POOL_INDIV;
@@ -397,7 +398,8 @@ multi_init(struct multi_context *m, struct context *t, bool
tcp_mode, int thread
pool_type = IFCONFIG_POOL_30NET;
}
- m->ifconfig_pool = ifconfig_pool_init(pool_type,
+ m->ifconfig_pool = ifconfig_pool_init(t->options.ifconfig_pool_defined,
+ pool_type,
t->options.ifconfig_pool_start,
t->options.ifconfig_pool_end,
t->options.duplicate_cn,
@@ -1495,7 +1497,9 @@ multi_select_virtual_addr(struct multi_context *m, struct
multi_instance *mi)
const int tunnel_topology = TUNNEL_TOPOLOGY(mi->context.c1.tuntap);
msg( M_INFO, "MULTI_sva: pool returned IPv4=%s, IPv6=%s",
- print_in_addr_t( remote, 0, &gc ),
+ (mi->context.options.ifconfig_pool_defined
+ ? print_in_addr_t(remote, 0, &gc)
+ : "(Not enabled)"),
(mi->context.options.ifconfig_ipv6_pool_defined
? print_in6_addr( remote_ipv6, 0, &gc )
: "(Not enabled)") );
diff --git a/src/openvpn/pool.c b/src/openvpn/pool.c
index 6dd72bb9..48f3ec95 100644
--- a/src/openvpn/pool.c
+++ b/src/openvpn/pool.c
@@ -58,6 +58,29 @@ ifconfig_pool_entry_free(struct ifconfig_pool_entry *ipe,
bool hard)
}
}
+static const int
+ifconfig_pool_size(const struct ifconfig_pool *pool)
+{
+ int min = INT_MAX;
+
+ if (!pool->ipv4.enabled && !pool->ipv6.enabled)
+ {
+ return 0;
+ }
+
+ if (pool->ipv4.enabled)
+ {
+ min = pool->ipv4.size;
+ }
+
+ if (pool->ipv6.enabled && pool->ipv6.size < min)
+ {
+ min = pool->ipv6.size;
+ }
+
+ return min;
+}
+
static int
ifconfig_pool_find(struct ifconfig_pool *pool, const char *common_name)
{
@@ -65,8 +88,9 @@ ifconfig_pool_find(struct ifconfig_pool *pool, const char
*common_name)
time_t earliest_release = 0;
int previous_usage = -1;
int new_usage = -1;
+ int pool_size = ifconfig_pool_size(pool);
- for (i = 0; i < pool->ipv4.size; ++i)
+ for (i = 0; i < pool_size; ++i)
{
struct ifconfig_pool_entry *ipe = &pool->list[i];
if (!ipe->in_use)
@@ -147,34 +171,43 @@ ifconfig_pool_verify_range(const int msglevel, const
in_addr_t start, const in_a
}
struct ifconfig_pool *
-ifconfig_pool_init(enum pool_type type, in_addr_t start, in_addr_t end,
- const bool duplicate_cn,
+ifconfig_pool_init(const bool ipv4_pool, enum pool_type type, in_addr_t start,
+ in_addr_t end, const bool duplicate_cn,
const bool ipv6_pool, const struct in6_addr ipv6_base,
const int ipv6_netbits )
{
struct gc_arena gc = gc_new();
struct ifconfig_pool *pool = NULL;
+ int pool_size = -1;
ASSERT(start <= end && end - start < IFCONFIG_POOL_MAX);
ALLOC_OBJ_CLEAR(pool, struct ifconfig_pool);
- pool->ipv4.type = type;
pool->duplicate_cn = duplicate_cn;
- switch (pool->ipv4.type)
+ pool->ipv4.enabled = ipv4_pool;
+
+ if (pool->ipv4.enabled)
{
- case IFCONFIG_POOL_30NET:
- pool->ipv4.base = start & ~3;
- pool->ipv4.size = (((end | 3) + 1) - pool->ipv4.base) >> 2;
- break;
+ pool->ipv4.type = type;
+ switch (pool->ipv4.type)
+ {
+ case IFCONFIG_POOL_30NET:
+ pool->ipv4.base = start & ~3;
+ pool->ipv4.size = (((end | 3) + 1) - pool->ipv4.base) >> 2;
+ break;
- case IFCONFIG_POOL_INDIV:
- pool->ipv4.base = start;
- pool->ipv4.size = end - start + 1;
- break;
+ case IFCONFIG_POOL_INDIV:
+ pool->ipv4.base = start;
+ pool->ipv4.size = end - start + 1;
+ break;
- default:
- ASSERT(0);
+ default:
+ ASSERT(0);
+ }
+
+ msg(D_IFCONFIG_POOL, "IFCONFIG POOL: base=%s size=%d",
+ print_in_addr_t(pool->ipv4.base, 0, &gc), pool->ipv4.size);
}
/* IPv6 pools are always "INDIV" type */
@@ -182,26 +215,60 @@ ifconfig_pool_init(enum pool_type type, in_addr_t start,
in_addr_t end,
if (pool->ipv6.enabled)
{
+ /* the host portion of the address will always be contained in the last
+ * 4 bytes, therefore we can just extract that and use it as base in
+ * integer form
+ */
+ uint32_t base = (ipv6_base.s6_addr[12] << 24)
+ | (ipv6_base.s6_addr[13] << 16)
+ | (ipv6_base.s6_addr[14] << 8)
+ | ipv6_base.s6_addr[15];
+ /* some bits of the last 4 bytes may still be part of the network
+ * portion of the address, therefore we need to set them to 0
+ */
+ if ((128 - ipv6_netbits) < 32)
+ {
+ /* extract only the bits that are really part of the host portion
of
+ * the address.
+ *
+ * Example: if we have netbits=31, the first bit has to be zero'd,
+ * the following operation first computes off=0x3fffff and then
uses
+ * mask to extract the wanted bits from base
+ */
+ uint32_t mask = (1 << (128 - ipv6_netbits - 1)) - 1;
+ base &= mask;
+ }
+
pool->ipv6.base = ipv6_base;
- pool->ipv6.size = ipv6_netbits > 112 ? (1 << (128 - ipv6_netbits))
+ pool->ipv6.size = ipv6_netbits > 112
+ ? (1 << (128 - ipv6_netbits)) - base
: IFCONFIG_POOL_MAX;
- msg( D_IFCONFIG_POOL, "IFCONFIG POOL IPv6: (IPv4) size=%d,
size_ipv6=%d, netbits=%d, base_ipv6=%s",
- pool->ipv4.size, pool->ipv6.size, ipv6_netbits,
- print_in6_addr(pool->ipv6.base, 0, &gc));
+ msg(D_IFCONFIG_POOL, "IFCONFIG POOL IPv6: base=%s size=%d netbits=%d",
+ print_in6_addr(pool->ipv6.base, 0, &gc), pool->ipv6.size,
+ ipv6_netbits);
+ }
- /* the current code is very simple and assumes that the IPv6
- * pool is at least as big as the IPv4 pool, and we don't need
- * to do separate math etc. for IPv6
- */
- ASSERT(pool->ipv4.size < pool->ipv6.size);
+ if (pool->ipv4.enabled && pool->ipv6.enabled)
+ {
+ if (pool->ipv4.size < pool->ipv6.size)
+ {
+ msg(M_INFO, "NOTE: IPv4 pool size is %d, IPv6 pool size is %d. "
+ "IPv4 pool size limits the number of clients that can be "
+ "served from the pool", pool->ipv4.size, pool->ipv6.size);
+ }
+ else if (pool->ipv4.size > pool->ipv6.size)
+ {
+ msg(M_WARN, "WARNING: IPv4 pool size is %d, IPv6 pool size is %d. "
+ "IPv6 pool size limits the number of clients that can be "
+ "served from the pool. This is likely a MISTAKE - please check
"
+ "your configuration", pool->ipv4.size, pool->ipv6.size);
+ }
}
- ALLOC_ARRAY_CLEAR(pool->list, struct ifconfig_pool_entry, pool->ipv4.size);
+ pool_size = ifconfig_pool_size(pool);
- msg(D_IFCONFIG_POOL, "IFCONFIG POOL: base=%s size=%d, ipv6=%d",
- print_in_addr_t(pool->ipv4.base, 0, &gc),
- pool->ipv4.size, pool->ipv6.enabled);
+ ALLOC_ARRAY_CLEAR(pool->list, struct ifconfig_pool_entry, pool_size);
gc_free(&gc);
return pool;
@@ -212,8 +279,9 @@ ifconfig_pool_free(struct ifconfig_pool *pool)
{
if (pool)
{
- int i;
- for (i = 0; i < pool->ipv4.size; ++i)
+ int i, pool_size = ifconfig_pool_size(pool);
+
+ for (i = 0; i < pool_size; ++i)
{
ifconfig_pool_entry_free(&pool->list[i], true);
}
@@ -239,26 +307,29 @@ ifconfig_pool_acquire(struct ifconfig_pool *pool,
in_addr_t *local, in_addr_t *r
ipe->common_name = string_alloc(common_name, NULL);
}
- switch (pool->ipv4.type)
+ if (pool->ipv4.enabled && local && remote)
{
- case IFCONFIG_POOL_30NET:
+ switch (pool->ipv4.type)
{
- in_addr_t b = pool->ipv4.base + (i << 2);
- *local = b + 1;
- *remote = b + 2;
- break;
- }
+ case IFCONFIG_POOL_30NET:
+ {
+ in_addr_t b = pool->ipv4.base + (i << 2);
+ *local = b + 1;
+ *remote = b + 2;
+ break;
+ }
- case IFCONFIG_POOL_INDIV:
- {
- in_addr_t b = pool->ipv4.base + i;
- *local = 0;
- *remote = b;
- break;
- }
+ case IFCONFIG_POOL_INDIV:
+ {
+ in_addr_t b = pool->ipv4.base + i;
+ *local = 0;
+ *remote = b;
+ break;
+ }
- default:
- ASSERT(0);
+ default:
+ ASSERT(0);
+ }
}
/* IPv6 pools are always INDIV (--linear) */
@@ -274,7 +345,9 @@ bool
ifconfig_pool_release(struct ifconfig_pool *pool, ifconfig_pool_handle hand,
const bool hard)
{
bool ret = false;
- if (pool && hand >= 0 && hand < pool->ipv4.size)
+ int pool_size = ifconfig_pool_size(pool);
+
+ if (pool && hand >= 0 && hand < pool_size)
{
ifconfig_pool_entry_free(&pool->list[hand], hard);
ret = true;
@@ -286,6 +359,7 @@ ifconfig_pool_release(struct ifconfig_pool *pool,
ifconfig_pool_handle hand, con
* private access functions
*/
+/* currently handling IPv4 logic only */
static ifconfig_pool_handle
ifconfig_pool_ip_base_to_handle(const struct ifconfig_pool *pool, const
in_addr_t addr)
{
@@ -380,9 +454,9 @@ ifconfig_pool_list(const struct ifconfig_pool *pool, struct
status_output *out)
if (pool && out)
{
struct gc_arena gc = gc_new();
- int i;
+ int i, pool_size = ifconfig_pool_size(pool);
- for (i = 0; i < pool->ipv4.size; ++i)
+ for (i = 0; i < pool_size; ++i)
{
const struct ifconfig_pool_entry *e = &pool->list[i];
if (e->common_name)
@@ -475,6 +549,15 @@ ifconfig_pool_read(struct ifconfig_pool_persist *persist,
struct ifconfig_pool *
const int buf_size = 128;
update_time();
+
+ /* IPv6 logic not implemented yet, therefore bail out if no IPv4 pool was
+ * configured
+ */
+ if (pool && !pool->ipv4.enabled)
+ {
+ return;
+ }
+
if (persist && persist->file && pool)
{
struct gc_arena gc = gc_new();
diff --git a/src/openvpn/pool.h b/src/openvpn/pool.h
index 73ea5599..6af04645 100644
--- a/src/openvpn/pool.h
+++ b/src/openvpn/pool.h
@@ -52,6 +52,7 @@ struct ifconfig_pool
{
bool duplicate_cn;
struct {
+ bool enabled;
enum pool_type type;
in_addr_t base;
int size;
@@ -72,7 +73,12 @@ struct ifconfig_pool_persist
typedef int ifconfig_pool_handle;
-struct ifconfig_pool *ifconfig_pool_init(enum pool_type type, in_addr_t start,
in_addr_t end, const bool duplicate_cn, const bool ipv6_pool, const struct
in6_addr ipv6_base, const int ipv6_netbits );
+struct ifconfig_pool *ifconfig_pool_init(const bool ipv4_pool,
+ enum pool_type type, in_addr_t start,
+ in_addr_t end, const bool
duplicate_cn,
+ const bool ipv6_pool,
+ const struct in6_addr ipv6_base,
+ const int ipv6_netbits);
void ifconfig_pool_free(struct ifconfig_pool *pool);
--
2.26.2
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