kernel: Add options to control DF and ECN header bits/fields via XFRM

The options control whether the DF and ECN header bits/fields are copied
from the unencrypted packets to the encrypted packets in tunnel mode (DF only
for IPv4), and for ECN whether the same is done for inbound packets.

Note: This implementation only works with Linux/Netlink/XFRM.

Based on a patch by Markus Sattler.
This commit is contained in:
Tobias Brunner
2018-08-29 11:36:04 +02:00
parent de4c3d2e76
commit dc8b015d78
6 changed files with 80 additions and 14 deletions
+42 -14
View File
@@ -484,7 +484,6 @@ typedef struct {
linked_list_t *local_ts;
linked_list_t *remote_ts;
uint32_t replay_window;
bool policies;
child_cfg_create_t cfg;
} child_data_t;
@@ -511,7 +510,7 @@ static void log_child_data(child_data_t *data, char *name)
DBG2(DBG_CFG, " ipcomp = %u", has_opt(OPT_IPCOMP));
DBG2(DBG_CFG, " mode = %N%s", ipsec_mode_names, cfg->mode,
has_opt(OPT_PROXY_MODE) ? "_PROXY" : "");
DBG2(DBG_CFG, " policies = %u", data->policies);
DBG2(DBG_CFG, " policies = %u", !has_opt(OPT_NO_POLICIES));
DBG2(DBG_CFG, " policies_fwd_out = %u", has_opt(OPT_FWD_OUT_POLICIES));
if (data->replay_window != REPLAY_UNDEFINED)
{
@@ -535,6 +534,8 @@ static void log_child_data(child_data_t *data, char *name)
DBG2(DBG_CFG, " remote_ts = %#R", data->remote_ts);
DBG2(DBG_CFG, " hw_offload = %N", hw_offload_names, cfg->hw_offload);
DBG2(DBG_CFG, " sha256_96 = %u", has_opt(OPT_SHA256_96));
DBG2(DBG_CFG, " copy_df = %u", !has_opt(OPT_NO_COPY_DF));
DBG2(DBG_CFG, " copy_ecn = %u", !has_opt(OPT_NO_COPY_ECN));
}
/**
@@ -847,16 +848,17 @@ CALLBACK(parse_mode, bool,
}
/**
* Enable a child_cfg_option_t
* Enable a child_cfg_option_t, the flag controls whether the option is enabled
* if the parsed value is TRUE or FALSE.
*/
static bool parse_option(child_cfg_option_t *out, child_cfg_option_t opt,
chunk_t v)
chunk_t v, bool add_if_true)
{
bool val;
if (parse_bool(&val, v))
{
if (val)
if (val == add_if_true)
{
*out |= opt;
}
@@ -871,7 +873,16 @@ static bool parse_option(child_cfg_option_t *out, child_cfg_option_t opt,
CALLBACK(parse_opt_haccess, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_HOSTACCESS, v);
return parse_option(out, OPT_HOSTACCESS, v, TRUE);
}
/**
* Parse OPT_NO_POLICIES option
*/
CALLBACK(parse_opt_policies, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_NO_POLICIES, v, FALSE);
}
/**
@@ -880,7 +891,7 @@ CALLBACK(parse_opt_haccess, bool,
CALLBACK(parse_opt_fwd_out, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_FWD_OUT_POLICIES, v);
return parse_option(out, OPT_FWD_OUT_POLICIES, v, TRUE);
}
/**
@@ -889,17 +900,16 @@ CALLBACK(parse_opt_fwd_out, bool,
CALLBACK(parse_opt_ipcomp, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_IPCOMP, v);
return parse_option(out, OPT_IPCOMP, v, TRUE);
}
/**
* Parse OPT_SHA256_96 option
*/
CALLBACK(parse_opt_sha256_96, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_SHA256_96, v);
return parse_option(out, OPT_SHA256_96, v, TRUE);
}
/**
@@ -908,7 +918,25 @@ CALLBACK(parse_opt_sha256_96, bool,
CALLBACK(parse_opt_mark_in, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_MARK_IN_SA, v);
return parse_option(out, OPT_MARK_IN_SA, v, TRUE);
}
/**
* Parse OPT_NO_COPY_DF option
*/
CALLBACK(parse_opt_copy_df, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_NO_COPY_DF, v, FALSE);
}
/**
* Parse OPT_NO_COPY_ECN option
*/
CALLBACK(parse_opt_copy_ecn, bool,
child_cfg_option_t *out, chunk_t v)
{
return parse_option(out, OPT_NO_COPY_ECN, v, FALSE);
}
/**
@@ -1567,7 +1595,7 @@ CALLBACK(child_kv, bool,
{ "updown", parse_string, &child->cfg.updown },
{ "hostaccess", parse_opt_haccess, &child->cfg.options },
{ "mode", parse_mode, &child->cfg },
{ "policies", parse_bool, &child->policies },
{ "policies", parse_opt_policies, &child->cfg.options },
{ "policies_fwd_out", parse_opt_fwd_out, &child->cfg.options },
{ "replay_window", parse_uint32, &child->replay_window },
{ "rekey_time", parse_time, &child->cfg.lifetime.time.rekey },
@@ -1593,6 +1621,8 @@ CALLBACK(child_kv, bool,
{ "interface", parse_string, &child->cfg.interface },
{ "hw_offload", parse_hw_offload, &child->cfg.hw_offload },
{ "sha256_96", parse_opt_sha256_96,&child->cfg.options },
{ "copy_df", parse_opt_copy_df, &child->cfg.options },
{ "copy_ecn", parse_opt_copy_ecn, &child->cfg.options },
};
return parse_rules(rules, countof(rules), name, value,
@@ -1802,7 +1832,6 @@ CALLBACK(children_sn, bool,
.proposals = linked_list_create(),
.local_ts = linked_list_create(),
.remote_ts = linked_list_create(),
.policies = TRUE,
.replay_window = REPLAY_UNDEFINED,
.cfg = {
.mode = MODE_TUNNEL,
@@ -1858,7 +1887,6 @@ CALLBACK(children_sn, bool,
child.proposals->insert_last(child.proposals, proposal);
}
}
child.cfg.options |= child.policies ? 0 : OPT_NO_POLICIES;
check_lifetimes(&child.cfg.lifetime);