Extend the parsing of forwarding rules (-[tu]) to allow the destination
address on the target side to be specified. For now just parse them, and
give an error if we try to create rules with a specified target address.
We'll implement the actual forwarding logic in another patch.
Format (for either command line or pesto):
-t 2222:192.0.2.1/2222
This should work along with all the other bits, that is, say:
-t 192.0.2.1%eth0/2222-2225:192.0.2.2/22-25
FIXME: Ban for -[TU] for now
FIXME: Check interaction with splice handling
Signed-off-by: Stefano Brivio
[dwg: Syntax from Stefano's earlier draft, largely rewritten on top of new
parsing helpers]
Signed-off-by: David Gibson
---
fwd_rule.c | 38 +++++++++++++++++++++++++++++++-------
1 file changed, 31 insertions(+), 7 deletions(-)
diff --git a/fwd_rule.c b/fwd_rule.c
index ca409eaf..e8abc884 100644
--- a/fwd_rule.c
+++ b/fwd_rule.c
@@ -378,14 +378,17 @@ int fwd_rule_add(struct fwd_table *fwd, const struct fwd_rule *new)
* @first: First port to forward
* @last: Last port to forward
* @exclude: Bitmap of ports to exclude (may be NULL)
- * @to: Port to translate @first to when forwarding
+ * @tgt_addr: Destination address on the target side
+ * @tgt_first: Destination port to use for @first on the traget side
* @flags: Flags for forwarding entries
*/
static void fwd_rule_range_except(struct fwd_table *fwd, bool del,
uint8_t proto, const union inany_addr *addr,
const char *ifname,
uint16_t first, uint16_t last,
- const uint8_t *exclude, uint16_t to,
+ const uint8_t *exclude,
+ const union inany_addr *tgt_addr,
+ uint16_t tgt_first,
uint8_t flags)
{
struct fwd_rule rule = {
@@ -395,9 +398,17 @@ static void fwd_rule_range_except(struct fwd_table *fwd, bool del,
.flags = flags,
};
char rulestr[FWD_RULE_STRLEN];
- unsigned delta = to - first;
+ unsigned delta = tgt_first - first;
unsigned base, i;
+ if (tgt_addr && !inany_is_unspecified(tgt_addr)) {
+ char astr[INANY_ADDRSTRLEN];
+
+ info("Target address: %s",
+ inany_ntop(tgt_addr, astr, sizeof(astr)));
+ die("Target address remapping not yet implemented");
+ }
+
if (!addr)
rule.flags |= FWD_DUAL_STACK_ANY;
if (ifname) {
@@ -458,14 +469,17 @@ enum fwd_port_chunk_kind {
* @cursor: Parsing point (see parse.c)
* @kindp: Updated with kind of chunk we parsed
* @lrange: Updated with listening port range (for INCLUDE & EXCLUDE)
+ * @taddr: Updated with target address (for INCLUDE)
* @trange: Updated with target port range (for INCLUDE)
*/
static bool parse_port_chunk(const char **cursor,
enum fwd_port_chunk_kind *kindp,
struct port_range *lrange,
+ union inany_addr *taddr,
struct port_range *trange)
{
struct port_range lr = { 0 }, tr = { 0 };
+ union inany_addr taddr_tmp = inany_any6;
enum fwd_port_chunk_kind kind;
const char *p = *cursor;
@@ -481,6 +495,12 @@ static bool parse_port_chunk(const char **cursor,
kind = CHUNK_INCLUDE;
if (parse_literal(&p, ":")) {
+ const char *tgtspec = p;
+
+ if (!parse_inany(&p, &taddr_tmp) ||
+ !parse_literal(&p, "/"))
+ p = tgtspec; /* No target address, backtrack */
+
if (!parse_port_range(&p, &tr))
return false;
} else {
@@ -492,6 +512,8 @@ static bool parse_port_chunk(const char **cursor,
*kindp = kind;
*lrange = lr;
+ if (taddr)
+ *taddr = taddr_tmp;
if (trange)
*trange = tr;
*cursor = p;
@@ -561,7 +583,7 @@ static void fwd_rule_parse_ports(struct fwd_table *fwd, bool del, uint8_t proto,
/* Consider excluded ranges and "auto" in the first pass */
p = spec;
do {
- if (!parse_port_chunk(&p, &kind, &lrange, NULL))
+ if (!parse_port_chunk(&p, &kind, &lrange, NULL, NULL))
goto bad;
switch (kind) {
@@ -586,8 +608,9 @@ static void fwd_rule_parse_ports(struct fwd_table *fwd, bool del, uint8_t proto,
p = spec;
do {
struct port_range trange;
+ union inany_addr taddr;
- if (!parse_port_chunk(&p, &kind, &lrange, &trange))
+ if (!parse_port_chunk(&p, &kind, &lrange, &taddr, &trange))
goto bad;
switch (kind) {
@@ -604,7 +627,8 @@ static void fwd_rule_parse_ports(struct fwd_table *fwd, bool del, uint8_t proto,
fwd_rule_range_except(fwd, del, proto, addr, ifname,
lrange.first, lrange.last,
- exclude, trange.first, flags);
+ exclude, &taddr, trange.first,
+ flags);
break;
default:
goto bad;
@@ -620,7 +644,7 @@ static void fwd_rule_parse_ports(struct fwd_table *fwd, bool del, uint8_t proto,
fwd_rule_range_except(fwd, del, proto, addr, ifname,
1, NUM_PORTS - 1, exclude,
- 1, flags | FWD_WEAK);
+ NULL, 1, flags | FWD_WEAK);
}
return;
bad:
--
2.54.0