* [iptables PATCH 1/9] man: DNAT: Describe shifted port range feature
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 2/9] Revert "libipt_[SD]NAT: avoid false error about multiple destinations specified" Phil Sutter
` (7 subsequent siblings)
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
This wasn't mentioned anywhere.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/libxt_DNAT.man | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/extensions/libxt_DNAT.man b/extensions/libxt_DNAT.man
index c3daea9a40394..e044c8216fc09 100644
--- a/extensions/libxt_DNAT.man
+++ b/extensions/libxt_DNAT.man
@@ -10,7 +10,7 @@ should be modified (and all future packets in this connection will
also be mangled), and rules should cease being examined. It takes the
following options:
.TP
-\fB\-\-to\-destination\fP [\fIipaddr\fP[\fB\-\fP\fIipaddr\fP]][\fB:\fP\fIport\fP[\fB\-\fP\fIport\fP]]
+\fB\-\-to\-destination\fP [\fIipaddr\fP[\fB\-\fP\fIipaddr\fP]][\fB:\fP\fIport\fP[\fB\-\fP\fIport\fP[\fB/\fIbaseport\fP]]]
which can specify a single new destination IP address, an inclusive
range of IP addresses. Optionally a port range,
if the rule also specifies one of the following protocols:
@@ -18,6 +18,9 @@ if the rule also specifies one of the following protocols:
If no port range is specified, then the destination port will never be
modified. If no IP address is specified then only the destination port
will be modified.
+If \fBbaseport\fP is given, the difference of the original destination port and
+its value is used as offset into the mapping port range. This allows to create
+shifted portmap ranges and is available since kernel version 4.18.
.TP
\fB\-\-random\fP
If option
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [iptables PATCH 2/9] Revert "libipt_[SD]NAT: avoid false error about multiple destinations specified"
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 1/9] man: DNAT: Describe shifted port range feature Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 3/9] extensions: ipt_DNAT: Merge v1 and v2 parsers Phil Sutter
` (6 subsequent siblings)
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
This reverts commit f25b2355e889290879c8cecad3dd24ec0c384fb8.
The workaround is not needed anymore since commit 30b178b9bf11e
("extensions: *NAT: Kill multiple IPv4 range support").
While being at it, drop the same hidden flag logic from
libip6t_[SD]NAT extensions as well and just don't set XTOPT_MULTI so
guided option parser will reject multiple parameters automatically.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/libip6t_DNAT.c | 9 +--------
extensions/libip6t_SNAT.c | 9 +--------
extensions/libipt_DNAT.c | 8 ++------
extensions/libipt_SNAT.c | 3 ---
4 files changed, 4 insertions(+), 25 deletions(-)
diff --git a/extensions/libip6t_DNAT.c b/extensions/libip6t_DNAT.c
index f1ad81436316b..d51994c09e7f2 100644
--- a/extensions/libip6t_DNAT.c
+++ b/extensions/libip6t_DNAT.c
@@ -19,10 +19,8 @@ enum {
O_TO_DEST = 0,
O_RANDOM,
O_PERSISTENT,
- O_X_TO_DEST,
F_TO_DEST = 1 << O_TO_DEST,
F_RANDOM = 1 << O_RANDOM,
- F_X_TO_DEST = 1 << O_X_TO_DEST,
};
static void DNAT_help(void)
@@ -45,7 +43,7 @@ static void DNAT_help_v2(void)
static const struct xt_option_entry DNAT_opts[] = {
{.name = "to-destination", .id = O_TO_DEST, .type = XTTYPE_STRING,
- .flags = XTOPT_MAND | XTOPT_MULTI},
+ .flags = XTOPT_MAND},
{.name = "random", .id = O_RANDOM, .type = XTTYPE_NONE},
{.name = "persistent", .id = O_PERSISTENT, .type = XTTYPE_NONE},
XTOPT_TABLEEND,
@@ -183,12 +181,7 @@ static void _DNAT_parse(struct xt_option_call *cb,
xtables_option_parse(cb);
switch (cb->entry->id) {
case O_TO_DEST:
- if (cb->xflags & F_X_TO_DEST) {
- xtables_error(PARAMETER_PROBLEM,
- "DNAT: Multiple --to-destination not supported");
- }
parse_to(cb->arg, portok, range, rev);
- cb->xflags |= F_X_TO_DEST;
break;
case O_PERSISTENT:
range->flags |= NF_NAT_RANGE_PERSISTENT;
diff --git a/extensions/libip6t_SNAT.c b/extensions/libip6t_SNAT.c
index 6d19614c7c708..4fe272b262a3d 100644
--- a/extensions/libip6t_SNAT.c
+++ b/extensions/libip6t_SNAT.c
@@ -20,11 +20,9 @@ enum {
O_RANDOM,
O_RANDOM_FULLY,
O_PERSISTENT,
- O_X_TO_SRC,
F_TO_SRC = 1 << O_TO_SRC,
F_RANDOM = 1 << O_RANDOM,
F_RANDOM_FULLY = 1 << O_RANDOM_FULLY,
- F_X_TO_SRC = 1 << O_X_TO_SRC,
};
static void SNAT_help(void)
@@ -38,7 +36,7 @@ static void SNAT_help(void)
static const struct xt_option_entry SNAT_opts[] = {
{.name = "to-source", .id = O_TO_SRC, .type = XTTYPE_STRING,
- .flags = XTOPT_MAND | XTOPT_MULTI},
+ .flags = XTOPT_MAND},
{.name = "random", .id = O_RANDOM, .type = XTTYPE_NONE},
{.name = "random-fully", .id = O_RANDOM_FULLY, .type = XTTYPE_NONE},
{.name = "persistent", .id = O_PERSISTENT, .type = XTTYPE_NONE},
@@ -163,12 +161,7 @@ static void SNAT_parse(struct xt_option_call *cb)
xtables_option_parse(cb);
switch (cb->entry->id) {
case O_TO_SRC:
- if (cb->xflags & F_X_TO_SRC) {
- xtables_error(PARAMETER_PROBLEM,
- "SNAT: Multiple --to-source not supported");
- }
parse_to(cb->arg, portok, range);
- cb->xflags |= F_X_TO_SRC;
break;
case O_PERSISTENT:
range->flags |= NF_NAT_RANGE_PERSISTENT;
diff --git a/extensions/libipt_DNAT.c b/extensions/libipt_DNAT.c
index eefa95eb73630..e93ab6958969b 100644
--- a/extensions/libipt_DNAT.c
+++ b/extensions/libipt_DNAT.c
@@ -12,10 +12,8 @@ enum {
O_TO_DEST = 0,
O_RANDOM,
O_PERSISTENT,
- O_X_TO_DEST, /* hidden flag */
- F_TO_DEST = 1 << O_TO_DEST,
- F_RANDOM = 1 << O_RANDOM,
- F_X_TO_DEST = 1 << O_X_TO_DEST,
+ F_TO_DEST = 1 << O_TO_DEST,
+ F_RANDOM = 1 << O_RANDOM,
};
static void DNAT_help(void)
@@ -145,7 +143,6 @@ static void DNAT_parse(struct xt_option_call *cb)
switch (cb->entry->id) {
case O_TO_DEST:
parse_to(cb->arg, portok, mr->range);
- cb->xflags |= F_X_TO_DEST;
break;
case O_PERSISTENT:
mr->range->flags |= NF_NAT_RANGE_PERSISTENT;
@@ -367,7 +364,6 @@ static void DNAT_parse_v2(struct xt_option_call *cb)
switch (cb->entry->id) {
case O_TO_DEST:
parse_to_v2(cb->arg, portok, range);
- cb->xflags |= F_X_TO_DEST;
break;
case O_PERSISTENT:
range->flags |= NF_NAT_RANGE_PERSISTENT;
diff --git a/extensions/libipt_SNAT.c b/extensions/libipt_SNAT.c
index bd36830ae91ce..211a20bc45bfe 100644
--- a/extensions/libipt_SNAT.c
+++ b/extensions/libipt_SNAT.c
@@ -13,11 +13,9 @@ enum {
O_RANDOM,
O_RANDOM_FULLY,
O_PERSISTENT,
- O_X_TO_SRC,
F_TO_SRC = 1 << O_TO_SRC,
F_RANDOM = 1 << O_RANDOM,
F_RANDOM_FULLY = 1 << O_RANDOM_FULLY,
- F_X_TO_SRC = 1 << O_X_TO_SRC,
};
static void SNAT_help(void)
@@ -139,7 +137,6 @@ static void SNAT_parse(struct xt_option_call *cb)
switch (cb->entry->id) {
case O_TO_SRC:
parse_to(cb->arg, portok, mr->range);
- cb->xflags |= F_X_TO_SRC;
break;
case O_PERSISTENT:
mr->range->flags |= NF_NAT_RANGE_PERSISTENT;
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [iptables PATCH 3/9] extensions: ipt_DNAT: Merge v1 and v2 parsers
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 1/9] man: DNAT: Describe shifted port range feature Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 2/9] Revert "libipt_[SD]NAT: avoid false error about multiple destinations specified" Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 4/9] extensions: ipt_DNAT: Merge v1/v2 print/save code Phil Sutter
` (5 subsequent siblings)
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
Use v2 parser for both and copy field values into v1 data structure if
needed.
While being at it:
* Introduce parse_ports() function similar to the one in
libipt_REDIRECT.c.
* Use xtables_strtoui() in the above instead of atoi() for integrated
range checking.
* Parse IP addresses using inet_pton(), writing directly into
struct nf_nat_range2 fields.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/libipt_DNAT.c | 290 +++++++++++++++------------------------
1 file changed, 111 insertions(+), 179 deletions(-)
diff --git a/extensions/libipt_DNAT.c b/extensions/libipt_DNAT.c
index e93ab6958969b..2a7b1bc4ec0a6 100644
--- a/extensions/libipt_DNAT.c
+++ b/extensions/libipt_DNAT.c
@@ -5,6 +5,7 @@
#include <xtables.h>
#include <iptables.h> /* get_kernel_version */
#include <limits.h> /* INT_MAX in ip_tables.h */
+#include <arpa/inet.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter/nf_nat.h>
@@ -42,54 +43,83 @@ static const struct xt_option_entry DNAT_opts[] = {
XTOPT_TABLEEND,
};
+/* Parses ports */
+static void
+parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
+{
+ unsigned int port, maxport, baseport;
+ char *end = NULL;
+
+ if (!portok)
+ xtables_error(PARAMETER_PROBLEM,
+ "Need TCP, UDP, SCTP or DCCP with port specification");
+
+ range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
+
+ if (!xtables_strtoui(arg, &end, &port, 1, UINT16_MAX))
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
+
+ switch (*end) {
+ case '\0':
+ range->min_proto.tcp.port
+ = range->max_proto.tcp.port
+ = htons(port);
+ return;
+ case '-':
+ arg = end + 1;
+ break;
+ case ':':
+ xtables_error(PARAMETER_PROBLEM,
+ "Invalid port:port syntax - use dash");
+ default:
+ xtables_error(PARAMETER_PROBLEM,
+ "Garbage after port value: `%s'", end);
+ }
+
+ if (!xtables_strtoui(arg, &end, &maxport, 1, UINT16_MAX))
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
+
+ if (maxport < port)
+ /* People are stupid. */
+ xtables_error(PARAMETER_PROBLEM,
+ "Port range `%s' funky", arg);
+
+ range->min_proto.tcp.port = htons(port);
+ range->max_proto.tcp.port = htons(maxport);
+
+ switch (*end) {
+ case '\0':
+ return;
+ case '/':
+ arg = end + 1;
+ break;
+ default:
+ xtables_error(PARAMETER_PROBLEM,
+ "Garbage after port range: `%s'", end);
+ }
+
+ if (!xtables_strtoui(arg, &end, &baseport, 1, UINT16_MAX))
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
+
+ range->flags |= NF_NAT_RANGE_PROTO_OFFSET;
+ range->base_proto.tcp.port = htons(baseport);
+}
+
/* Ranges expected in network order. */
static void
-parse_to(const char *orig_arg, int portok, struct nf_nat_ipv4_range *range)
+parse_to(const char *orig_arg, bool portok, struct nf_nat_range2 *range)
{
- char *arg, *colon, *dash, *error;
- const struct in_addr *ip;
+ char *arg, *colon, *dash;
arg = xtables_strdup(orig_arg);
colon = strchr(arg, ':');
if (colon) {
- int port;
-
- if (!portok)
- xtables_error(PARAMETER_PROBLEM,
- "Need TCP, UDP, SCTP or DCCP with port specification");
-
- range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
+ parse_ports(colon + 1, portok, range);
- port = atoi(colon+1);
- if (port <= 0 || port > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", colon+1);
-
- error = strchr(colon+1, ':');
- if (error)
- xtables_error(PARAMETER_PROBLEM,
- "Invalid port:port syntax - use dash\n");
-
- dash = strchr(colon, '-');
- if (!dash) {
- range->min.tcp.port
- = range->max.tcp.port
- = htons(port);
- } else {
- int maxport;
-
- maxport = atoi(dash + 1);
- if (maxport <= 0 || maxport > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", dash+1);
- if (maxport < port)
- /* People are stupid. */
- xtables_error(PARAMETER_PROBLEM,
- "Port range `%s' funky\n", colon+1);
- range->min.tcp.port = htons(port);
- range->max.tcp.port = htons(maxport);
- }
/* Starts with a colon? No IP info...*/
if (colon == arg) {
free(arg);
@@ -106,46 +136,57 @@ parse_to(const char *orig_arg, int portok, struct nf_nat_ipv4_range *range)
if (dash)
*dash = '\0';
- ip = xtables_numeric_to_ipaddr(arg);
- if (!ip)
- xtables_error(PARAMETER_PROBLEM, "Bad IP address \"%s\"\n",
- arg);
- range->min_ip = ip->s_addr;
+ if (!inet_pton(AF_INET, arg, &range->min_addr))
+ xtables_error(PARAMETER_PROBLEM,
+ "Bad IP address \"%s\"\n", arg);
if (dash) {
- ip = xtables_numeric_to_ipaddr(dash+1);
- if (!ip)
- xtables_error(PARAMETER_PROBLEM, "Bad IP address \"%s\"\n",
- dash+1);
- range->max_ip = ip->s_addr;
- } else
- range->max_ip = range->min_ip;
-
+ if (!inet_pton(AF_INET, dash + 1, &range->max_addr))
+ xtables_error(PARAMETER_PROBLEM,
+ "Bad IP address \"%s\"\n", dash + 1);
+ } else {
+ range->max_addr = range->min_addr;
+ }
free(arg);
return;
}
+static void __DNAT_parse(struct xt_option_call *cb, __u16 proto,
+ struct nf_nat_range2 *range)
+{
+ bool portok = proto == IPPROTO_TCP ||
+ proto == IPPROTO_UDP ||
+ proto == IPPROTO_SCTP ||
+ proto == IPPROTO_DCCP ||
+ proto == IPPROTO_ICMP;
+
+ xtables_option_parse(cb);
+ switch (cb->entry->id) {
+ case O_TO_DEST:
+ parse_to(cb->arg, portok, range);
+ break;
+ case O_PERSISTENT:
+ range->flags |= NF_NAT_RANGE_PERSISTENT;
+ break;
+ }
+}
+
static void DNAT_parse(struct xt_option_call *cb)
{
struct nf_nat_ipv4_multi_range_compat *mr = (void *)cb->data;
const struct ipt_entry *entry = cb->xt_entry;
- int portok;
+ struct nf_nat_range2 range = {};
- if (entry->ip.proto == IPPROTO_TCP
- || entry->ip.proto == IPPROTO_UDP
- || entry->ip.proto == IPPROTO_SCTP
- || entry->ip.proto == IPPROTO_DCCP
- || entry->ip.proto == IPPROTO_ICMP)
- portok = 1;
- else
- portok = 0;
+ __DNAT_parse(cb, entry->ip.proto, &range);
- xtables_option_parse(cb);
switch (cb->entry->id) {
case O_TO_DEST:
- parse_to(cb->arg, portok, mr->range);
- break;
+ mr->range->min_ip = range.min_addr.ip;
+ mr->range->max_ip = range.max_addr.ip;
+ mr->range->min = range.min_proto;
+ mr->range->max = range.max_proto;
+ /* fall through */
case O_PERSISTENT:
- mr->range->flags |= NF_NAT_RANGE_PERSISTENT;
+ mr->range->flags |= range.flags;
break;
}
}
@@ -159,6 +200,10 @@ static void DNAT_fcheck(struct xt_fcheck_call *cb)
mr->range[0].flags |= NF_NAT_RANGE_PROTO_RANDOM;
mr->rangesize = 1;
+
+ if (mr->range[0].flags & NF_NAT_RANGE_PROTO_OFFSET)
+ xtables_error(PARAMETER_PROBLEM,
+ "Shifted portmap ranges not supported with this kernel");
}
static void print_range(const struct nf_nat_ipv4_range *r)
@@ -251,124 +296,11 @@ static int DNAT_xlate(struct xt_xlate *xl,
return 1;
}
-static void
-parse_to_v2(const char *orig_arg, int portok, struct nf_nat_range2 *range)
-{
- char *arg, *colon, *dash, *error;
- const struct in_addr *ip;
-
- arg = xtables_strdup(orig_arg);
-
- colon = strchr(arg, ':');
- if (colon) {
- int port;
-
- if (!portok)
- xtables_error(PARAMETER_PROBLEM,
- "Need TCP, UDP, SCTP or DCCP with port specification");
-
- range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
-
- port = atoi(colon+1);
- if (port <= 0 || port > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", colon+1);
-
- error = strchr(colon+1, ':');
- if (error)
- xtables_error(PARAMETER_PROBLEM,
- "Invalid port:port syntax - use dash\n");
-
- dash = strchr(colon, '-');
- if (!dash) {
- range->min_proto.tcp.port
- = range->max_proto.tcp.port
- = htons(port);
- } else {
- int maxport;
- char *slash;
-
- maxport = atoi(dash + 1);
- if (maxport <= 0 || maxport > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", dash+1);
- if (maxport < port)
- /* People are stupid. */
- xtables_error(PARAMETER_PROBLEM,
- "Port range `%s' funky\n", colon+1);
- range->min_proto.tcp.port = htons(port);
- range->max_proto.tcp.port = htons(maxport);
-
- slash = strchr(dash, '/');
- if (slash) {
- int baseport;
-
- baseport = atoi(slash + 1);
- if (baseport <= 0 || baseport > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", slash+1);
- range->flags |= NF_NAT_RANGE_PROTO_OFFSET;
- range->base_proto.tcp.port = htons(baseport);
- }
- }
- /* Starts with a colon? No IP info...*/
- if (colon == arg) {
- free(arg);
- return;
- }
- *colon = '\0';
- }
-
- range->flags |= NF_NAT_RANGE_MAP_IPS;
- dash = strchr(arg, '-');
- if (colon && dash && dash > colon)
- dash = NULL;
-
- if (dash)
- *dash = '\0';
-
- ip = xtables_numeric_to_ipaddr(arg);
- if (!ip)
- xtables_error(PARAMETER_PROBLEM, "Bad IP address \"%s\"\n",
- arg);
- range->min_addr.in = *ip;
- if (dash) {
- ip = xtables_numeric_to_ipaddr(dash+1);
- if (!ip)
- xtables_error(PARAMETER_PROBLEM, "Bad IP address \"%s\"\n",
- dash+1);
- range->max_addr.in = *ip;
- } else
- range->max_addr = range->min_addr;
-
- free(arg);
- return;
-}
-
static void DNAT_parse_v2(struct xt_option_call *cb)
{
const struct ipt_entry *entry = cb->xt_entry;
- struct nf_nat_range2 *range = cb->data;
- int portok;
-
- if (entry->ip.proto == IPPROTO_TCP
- || entry->ip.proto == IPPROTO_UDP
- || entry->ip.proto == IPPROTO_SCTP
- || entry->ip.proto == IPPROTO_DCCP
- || entry->ip.proto == IPPROTO_ICMP)
- portok = 1;
- else
- portok = 0;
- xtables_option_parse(cb);
- switch (cb->entry->id) {
- case O_TO_DEST:
- parse_to_v2(cb->arg, portok, range);
- break;
- case O_PERSISTENT:
- range->flags |= NF_NAT_RANGE_PERSISTENT;
- break;
- }
+ __DNAT_parse(cb, entry->ip.proto, cb->data);
}
static void DNAT_fcheck_v2(struct xt_fcheck_call *cb)
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [iptables PATCH 4/9] extensions: ipt_DNAT: Merge v1/v2 print/save code
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
` (2 preceding siblings ...)
2022-03-30 15:58 ` [iptables PATCH 3/9] extensions: ipt_DNAT: Merge v1 and v2 parsers Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 5/9] extensions: ipt_DNAT: Combine xlate functions also Phil Sutter
` (4 subsequent siblings)
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
Turn print_range() function into sprint_range() so it becomes more
versatile. Make it accept the new nf_nat_range2 data structure and
make v1 callers convert their nf_nat_ipv4_multi_range_compat structs
to that.
This allows to introduce an inner __DNAT_print() which acts for v1 and
v2 and prints either 'print' or 'save' syntax.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/libipt_DNAT.c | 111 ++++++++++++++++-----------------------
1 file changed, 46 insertions(+), 65 deletions(-)
diff --git a/extensions/libipt_DNAT.c b/extensions/libipt_DNAT.c
index 2a7b1bc4ec0a6..b72437d5e92f2 100644
--- a/extensions/libipt_DNAT.c
+++ b/extensions/libipt_DNAT.c
@@ -9,6 +9,15 @@
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter/nf_nat.h>
+#define TO_IPV4_MRC(ptr) ((const struct nf_nat_ipv4_multi_range_compat *)(ptr))
+#define RANGE2_INIT_FROM_IPV4_MRC(ptr) { \
+ .flags = TO_IPV4_MRC(ptr)->range[0].flags, \
+ .min_addr.ip = TO_IPV4_MRC(ptr)->range[0].min_ip, \
+ .max_addr.ip = TO_IPV4_MRC(ptr)->range[0].max_ip, \
+ .min_proto = TO_IPV4_MRC(ptr)->range[0].min, \
+ .max_proto = TO_IPV4_MRC(ptr)->range[0].max, \
+};
+
enum {
O_TO_DEST = 0,
O_RANDOM,
@@ -206,51 +215,55 @@ static void DNAT_fcheck(struct xt_fcheck_call *cb)
"Shifted portmap ranges not supported with this kernel");
}
-static void print_range(const struct nf_nat_ipv4_range *r)
+static char *sprint_range(const struct nf_nat_range2 *r)
{
- if (r->flags & NF_NAT_RANGE_MAP_IPS) {
- struct in_addr a;
+ static char buf[INET_ADDRSTRLEN * 2 + 1 + 6 * 3];
- a.s_addr = r->min_ip;
- printf("%s", xtables_ipaddr_to_numeric(&a));
- if (r->max_ip != r->min_ip) {
- a.s_addr = r->max_ip;
- printf("-%s", xtables_ipaddr_to_numeric(&a));
- }
+ if (r->flags & NF_NAT_RANGE_MAP_IPS) {
+ sprintf(buf, "%s", xtables_ipaddr_to_numeric(&r->min_addr.in));
+ if (memcmp(&r->min_addr, &r->max_addr, sizeof(r->min_addr)))
+ sprintf(buf + strlen(buf), "-%s",
+ xtables_ipaddr_to_numeric(&r->max_addr.in));
+ } else {
+ buf[0] = '\0';
}
if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- printf(":");
- printf("%hu", ntohs(r->min.tcp.port));
- if (r->max.tcp.port != r->min.tcp.port)
- printf("-%hu", ntohs(r->max.tcp.port));
+ sprintf(buf + strlen(buf), ":%hu",
+ ntohs(r->min_proto.tcp.port));
+ if (r->max_proto.tcp.port != r->min_proto.tcp.port)
+ sprintf(buf + strlen(buf), "-%hu",
+ ntohs(r->max_proto.tcp.port));
+ if (r->flags & NF_NAT_RANGE_PROTO_OFFSET)
+ sprintf(buf + strlen(buf), "/%hu",
+ ntohs(r->base_proto.tcp.port));
}
+ return buf;
+}
+
+static void __DNAT_print(const struct nf_nat_range2 *r, bool save)
+{
+ const char *dashdash = save ? "--" : "";
+
+ printf(" %s%s", save ? "--to-destination " : "to:", sprint_range(r));
+ if (r->flags & NF_NAT_RANGE_PROTO_RANDOM)
+ printf(" %srandom", dashdash);
+ if (r->flags & NF_NAT_RANGE_PERSISTENT)
+ printf(" %spersistent", dashdash);
}
static void DNAT_print(const void *ip, const struct xt_entry_target *target,
int numeric)
{
- const struct nf_nat_ipv4_multi_range_compat *mr =
- (const void *)target->data;
-
- printf(" to:");
- print_range(mr->range);
- if (mr->range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" random");
- if (mr->range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" persistent");
+ struct nf_nat_range2 range = RANGE2_INIT_FROM_IPV4_MRC(target->data);
+
+ __DNAT_print(&range, false);
}
static void DNAT_save(const void *ip, const struct xt_entry_target *target)
{
- const struct nf_nat_ipv4_multi_range_compat *mr =
- (const void *)target->data;
-
- printf(" --to-destination ");
- print_range(mr->range);
- if (mr->range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" --random");
- if (mr->range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" --persistent");
+ struct nf_nat_range2 range = RANGE2_INIT_FROM_IPV4_MRC(target->data);
+
+ __DNAT_print(&range, true);
}
static void print_range_xlate(const struct nf_nat_ipv4_range *r,
@@ -312,47 +325,15 @@ static void DNAT_fcheck_v2(struct xt_fcheck_call *cb)
range->flags |= NF_NAT_RANGE_PROTO_RANDOM;
}
-static void print_range_v2(const struct nf_nat_range2 *range)
-{
- if (range->flags & NF_NAT_RANGE_MAP_IPS) {
- printf("%s", xtables_ipaddr_to_numeric(&range->min_addr.in));
- if (memcmp(&range->min_addr, &range->max_addr,
- sizeof(range->min_addr)))
- printf("-%s", xtables_ipaddr_to_numeric(&range->max_addr.in));
- }
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- printf(":");
- printf("%hu", ntohs(range->min_proto.tcp.port));
- if (range->max_proto.tcp.port != range->min_proto.tcp.port)
- printf("-%hu", ntohs(range->max_proto.tcp.port));
- if (range->flags & NF_NAT_RANGE_PROTO_OFFSET)
- printf("/%hu", ntohs(range->base_proto.tcp.port));
- }
-}
-
static void DNAT_print_v2(const void *ip, const struct xt_entry_target *target,
int numeric)
{
- const struct nf_nat_range2 *range = (const void *)target->data;
-
- printf(" to:");
- print_range_v2(range);
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" random");
- if (range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" persistent");
+ __DNAT_print((const void *)target->data, false);
}
static void DNAT_save_v2(const void *ip, const struct xt_entry_target *target)
{
- const struct nf_nat_range2 *range = (const void *)target->data;
-
- printf(" --to-destination ");
- print_range_v2(range);
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" --random");
- if (range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" --persistent");
+ __DNAT_print((const void *)target->data, true);
}
static void print_range_xlate_v2(const struct nf_nat_range2 *range,
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [iptables PATCH 5/9] extensions: ipt_DNAT: Combine xlate functions also
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
` (3 preceding siblings ...)
2022-03-30 15:58 ` [iptables PATCH 4/9] extensions: ipt_DNAT: Merge v1/v2 print/save code Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 6/9] extensions: DNAT: Rename from libipt to libxt Phil Sutter
` (3 subsequent siblings)
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
Make use of the new sprint_range() to introduce a common inner function
for both v1 and v2 xlate functions.
Also abort translation with shifted port ranges to not hide the missing
feature in nftables.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/libipt_DNAT.c | 88 ++++++++++------------------------------
1 file changed, 21 insertions(+), 67 deletions(-)
diff --git a/extensions/libipt_DNAT.c b/extensions/libipt_DNAT.c
index b72437d5e92f2..9a179919f522d 100644
--- a/extensions/libipt_DNAT.c
+++ b/extensions/libipt_DNAT.c
@@ -266,47 +266,36 @@ static void DNAT_save(const void *ip, const struct xt_entry_target *target)
__DNAT_print(&range, true);
}
-static void print_range_xlate(const struct nf_nat_ipv4_range *r,
- struct xt_xlate *xl)
+static int __DNAT_xlate(struct xt_xlate *xl, const struct nf_nat_range2 *r)
{
- if (r->flags & NF_NAT_RANGE_MAP_IPS) {
- struct in_addr a;
+ char *range_str = sprint_range(r);
+ const char *sep = " ";
- a.s_addr = r->min_ip;
- xt_xlate_add(xl, "%s", xtables_ipaddr_to_numeric(&a));
- if (r->max_ip != r->min_ip) {
- a.s_addr = r->max_ip;
- xt_xlate_add(xl, "-%s", xtables_ipaddr_to_numeric(&a));
- }
+ /* shifted portmap ranges are not supported by nftables */
+ if (r->flags & NF_NAT_RANGE_PROTO_OFFSET)
+ return 0;
+
+ xt_xlate_add(xl, "dnat");
+ if (strlen(range_str))
+ xt_xlate_add(xl, " to %s", range_str);
+ if (r->flags & NF_NAT_RANGE_PROTO_RANDOM) {
+ xt_xlate_add(xl, "%srandom", sep);
+ sep = ",";
}
- if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- xt_xlate_add(xl, ":%hu", ntohs(r->min.tcp.port));
- if (r->max.tcp.port != r->min.tcp.port)
- xt_xlate_add(xl, "-%hu", ntohs(r->max.tcp.port));
+ if (r->flags & NF_NAT_RANGE_PERSISTENT) {
+ xt_xlate_add(xl, "%spersistent", sep);
+ sep = ",";
}
+ return 1;
}
static int DNAT_xlate(struct xt_xlate *xl,
const struct xt_xlate_tg_params *params)
{
- const struct nf_nat_ipv4_multi_range_compat *mr =
- (const void *)params->target->data;
- bool sep_need = false;
- const char *sep = " ";
-
- xt_xlate_add(xl, "dnat to ");
- print_range_xlate(mr->range, xl);
- if (mr->range->flags & NF_NAT_RANGE_PROTO_RANDOM) {
- xt_xlate_add(xl, " random");
- sep_need = true;
- }
- if (mr->range->flags & NF_NAT_RANGE_PERSISTENT) {
- if (sep_need)
- sep = ",";
- xt_xlate_add(xl, "%spersistent", sep);
- }
+ struct nf_nat_range2 range =
+ RANGE2_INIT_FROM_IPV4_MRC(params->target->data);
- return 1;
+ return __DNAT_xlate(xl, &range);
}
static void DNAT_parse_v2(struct xt_option_call *cb)
@@ -336,45 +325,10 @@ static void DNAT_save_v2(const void *ip, const struct xt_entry_target *target)
__DNAT_print((const void *)target->data, true);
}
-static void print_range_xlate_v2(const struct nf_nat_range2 *range,
- struct xt_xlate *xl)
-{
- if (range->flags & NF_NAT_RANGE_MAP_IPS) {
- xt_xlate_add(xl, "%s", xtables_ipaddr_to_numeric(&range->min_addr.in));
- if (memcmp(&range->min_addr, &range->max_addr,
- sizeof(range->min_addr))) {
- xt_xlate_add(xl, "-%s", xtables_ipaddr_to_numeric(&range->max_addr.in));
- }
- }
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- xt_xlate_add(xl, ":%hu", ntohs(range->min_proto.tcp.port));
- if (range->max_proto.tcp.port != range->min_proto.tcp.port)
- xt_xlate_add(xl, "-%hu", ntohs(range->max_proto.tcp.port));
- if (range->flags & NF_NAT_RANGE_PROTO_OFFSET)
- xt_xlate_add(xl, ";%hu", ntohs(range->base_proto.tcp.port));
- }
-}
-
static int DNAT_xlate_v2(struct xt_xlate *xl,
const struct xt_xlate_tg_params *params)
{
- const struct nf_nat_range2 *range = (const void *)params->target->data;
- bool sep_need = false;
- const char *sep = " ";
-
- xt_xlate_add(xl, "dnat to ");
- print_range_xlate_v2(range, xl);
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM) {
- xt_xlate_add(xl, " random");
- sep_need = true;
- }
- if (range->flags & NF_NAT_RANGE_PERSISTENT) {
- if (sep_need)
- sep = ",";
- xt_xlate_add(xl, "%spersistent", sep);
- }
-
- return 1;
+ return __DNAT_xlate(xl, (const void *)params->target->data);
}
static struct xtables_target dnat_tg_reg[] = {
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [iptables PATCH 6/9] extensions: DNAT: Rename from libipt to libxt
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
` (4 preceding siblings ...)
2022-03-30 15:58 ` [iptables PATCH 5/9] extensions: ipt_DNAT: Combine xlate functions also Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 7/9] extensions: Merge IPv4 and IPv6 DNAT targets Phil Sutter
` (2 subsequent siblings)
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
Prepare for merge of libipt and libip6t DNAT extensions, allow for
better code review.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/{libipt_DNAT.c => libxt_DNAT.c} | 0
1 file changed, 0 insertions(+), 0 deletions(-)
rename extensions/{libipt_DNAT.c => libxt_DNAT.c} (100%)
diff --git a/extensions/libipt_DNAT.c b/extensions/libxt_DNAT.c
similarity index 100%
rename from extensions/libipt_DNAT.c
rename to extensions/libxt_DNAT.c
--
2.34.1
^ permalink raw reply [flat|nested] 14+ messages in thread* [iptables PATCH 7/9] extensions: Merge IPv4 and IPv6 DNAT targets
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
` (5 preceding siblings ...)
2022-03-30 15:58 ` [iptables PATCH 6/9] extensions: DNAT: Rename from libipt to libxt Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 8/9] extensions: Merge REDIRECT into DNAT Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots Phil Sutter
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
Make parse_to() family-aware so it serves for both IPv4 and IPv6. Have a
core _DNAT_parse() function which parses into the most modern
(nf_nat_range2) data structure and a bunch of wrappers to copy into
legacy data structures if needed. Treat other callbacks analogous.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/libip6t_DNAT.c | 402 ---------------------------------
extensions/libip6t_DNAT.txlate | 11 -
extensions/libipt_DNAT.txlate | 14 --
extensions/libxt_DNAT.c | 222 ++++++++++++++----
extensions/libxt_DNAT.txlate | 35 +++
5 files changed, 216 insertions(+), 468 deletions(-)
delete mode 100644 extensions/libip6t_DNAT.c
delete mode 100644 extensions/libip6t_DNAT.txlate
delete mode 100644 extensions/libipt_DNAT.txlate
create mode 100644 extensions/libxt_DNAT.txlate
diff --git a/extensions/libip6t_DNAT.c b/extensions/libip6t_DNAT.c
deleted file mode 100644
index d51994c09e7f2..0000000000000
--- a/extensions/libip6t_DNAT.c
+++ /dev/null
@@ -1,402 +0,0 @@
-/*
- * Copyright (c) 2011 Patrick McHardy <kaber@trash.net>
- *
- * Based on Rusty Russell's IPv4 DNAT target. Development of IPv6 NAT
- * funded by Astaro.
- */
-
-#include <stdio.h>
-#include <netdb.h>
-#include <string.h>
-#include <stdlib.h>
-#include <xtables.h>
-#include <iptables.h>
-#include <limits.h> /* INT_MAX in ip_tables.h */
-#include <linux/netfilter_ipv6/ip6_tables.h>
-#include <linux/netfilter/nf_nat.h>
-
-enum {
- O_TO_DEST = 0,
- O_RANDOM,
- O_PERSISTENT,
- F_TO_DEST = 1 << O_TO_DEST,
- F_RANDOM = 1 << O_RANDOM,
-};
-
-static void DNAT_help(void)
-{
- printf(
-"DNAT target options:\n"
-" --to-destination [<ipaddr>[-<ipaddr>]][:port[-port]]\n"
-" Address to map destination to.\n"
-"[--random] [--persistent]\n");
-}
-
-static void DNAT_help_v2(void)
-{
- printf(
-"DNAT target options:\n"
-" --to-destination [<ipaddr>[-<ipaddr>]][:port[-port[/port]]]\n"
-" Address to map destination to.\n"
-"[--random] [--persistent]\n");
-}
-
-static const struct xt_option_entry DNAT_opts[] = {
- {.name = "to-destination", .id = O_TO_DEST, .type = XTTYPE_STRING,
- .flags = XTOPT_MAND},
- {.name = "random", .id = O_RANDOM, .type = XTTYPE_NONE},
- {.name = "persistent", .id = O_PERSISTENT, .type = XTTYPE_NONE},
- XTOPT_TABLEEND,
-};
-
-/* Ranges expected in network order. */
-static void
-parse_to(const char *orig_arg, int portok, struct nf_nat_range2 *range, int rev)
-{
- char *arg, *start, *end = NULL, *colon = NULL, *dash, *error;
- const struct in6_addr *ip;
-
- arg = xtables_strdup(orig_arg);
-
- start = strchr(arg, '[');
- if (start == NULL) {
- start = arg;
- /* Lets assume one colon is port information. Otherwise its an IPv6 address */
- colon = strchr(arg, ':');
- if (colon && strchr(colon+1, ':'))
- colon = NULL;
- }
- else {
- start++;
- end = strchr(start, ']');
- if (end == NULL)
- xtables_error(PARAMETER_PROBLEM,
- "Invalid address format");
-
- *end = '\0';
- colon = strchr(end + 1, ':');
- }
-
- if (colon) {
- int port;
-
- if (!portok)
- xtables_error(PARAMETER_PROBLEM,
- "Need TCP, UDP, SCTP or DCCP with port specification");
-
- range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
-
- port = atoi(colon+1);
- if (port <= 0 || port > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", colon+1);
-
- error = strchr(colon+1, ':');
- if (error)
- xtables_error(PARAMETER_PROBLEM,
- "Invalid port:port syntax - use dash\n");
-
- dash = strchr(colon, '-');
- if (!dash) {
- range->min_proto.tcp.port
- = range->max_proto.tcp.port
- = htons(port);
- } else {
- int maxport;
-
- maxport = atoi(dash + 1);
- if (maxport <= 0 || maxport > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", dash+1);
- if (maxport < port)
- /* People are stupid. */
- xtables_error(PARAMETER_PROBLEM,
- "Port range `%s' funky\n", colon+1);
- range->min_proto.tcp.port = htons(port);
- range->max_proto.tcp.port = htons(maxport);
-
- if (rev >= 2) {
- char *slash = strchr(dash, '/');
- if (slash) {
- int baseport;
-
- baseport = atoi(slash + 1);
- if (baseport <= 0 || baseport > 65535)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", slash+1);
- range->flags |= NF_NAT_RANGE_PROTO_OFFSET;
- range->base_proto.tcp.port = htons(baseport);
- }
- }
- }
- /* Starts with colon or [] colon? No IP info...*/
- if (colon == arg || colon == arg+2) {
- free(arg);
- return;
- }
- *colon = '\0';
- }
-
- range->flags |= NF_NAT_RANGE_MAP_IPS;
- dash = strchr(start, '-');
- if (colon && dash && dash > colon)
- dash = NULL;
-
- if (dash)
- *dash = '\0';
-
- ip = xtables_numeric_to_ip6addr(start);
- if (!ip)
- xtables_error(PARAMETER_PROBLEM, "Bad IP address \"%s\"\n",
- start);
- range->min_addr.in6 = *ip;
- if (dash) {
- ip = xtables_numeric_to_ip6addr(dash + 1);
- if (!ip)
- xtables_error(PARAMETER_PROBLEM, "Bad IP address \"%s\"\n",
- dash+1);
- range->max_addr.in6 = *ip;
- } else
- range->max_addr = range->min_addr;
-
- free(arg);
- return;
-}
-
-static void _DNAT_parse(struct xt_option_call *cb,
- struct nf_nat_range2 *range, int rev)
-{
- const struct ip6t_entry *entry = cb->xt_entry;
- int portok;
-
- if (entry->ipv6.proto == IPPROTO_TCP ||
- entry->ipv6.proto == IPPROTO_UDP ||
- entry->ipv6.proto == IPPROTO_SCTP ||
- entry->ipv6.proto == IPPROTO_DCCP ||
- entry->ipv6.proto == IPPROTO_ICMP)
- portok = 1;
- else
- portok = 0;
-
- xtables_option_parse(cb);
- switch (cb->entry->id) {
- case O_TO_DEST:
- parse_to(cb->arg, portok, range, rev);
- break;
- case O_PERSISTENT:
- range->flags |= NF_NAT_RANGE_PERSISTENT;
- break;
- }
-}
-
-static void DNAT_parse(struct xt_option_call *cb)
-{
- struct nf_nat_range *range_v1 = (void *)cb->data;
- struct nf_nat_range2 range = {};
-
- memcpy(&range, range_v1, sizeof(*range_v1));
- _DNAT_parse(cb, &range, 1);
- memcpy(range_v1, &range, sizeof(*range_v1));
-}
-
-static void DNAT_parse_v2(struct xt_option_call *cb)
-{
- _DNAT_parse(cb, (struct nf_nat_range2 *)cb->data, 2);
-}
-
-static void _DNAT_fcheck(struct xt_fcheck_call *cb, unsigned int *flags)
-{
- static const unsigned int f = F_TO_DEST | F_RANDOM;
-
- if ((cb->xflags & f) == f)
- *flags |= NF_NAT_RANGE_PROTO_RANDOM;
-}
-
-static void DNAT_fcheck(struct xt_fcheck_call *cb)
-{
- _DNAT_fcheck(cb, &((struct nf_nat_range *)cb->data)->flags);
-}
-
-static void DNAT_fcheck_v2(struct xt_fcheck_call *cb)
-{
- _DNAT_fcheck(cb, &((struct nf_nat_range2 *)cb->data)->flags);
-}
-
-static void print_range(const struct nf_nat_range2 *range, int rev)
-{
- if (range->flags & NF_NAT_RANGE_MAP_IPS) {
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED)
- printf("[");
- printf("%s", xtables_ip6addr_to_numeric(&range->min_addr.in6));
- if (memcmp(&range->min_addr, &range->max_addr,
- sizeof(range->min_addr)))
- printf("-%s", xtables_ip6addr_to_numeric(&range->max_addr.in6));
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED)
- printf("]");
- }
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- printf(":");
- printf("%hu", ntohs(range->min_proto.tcp.port));
- if (range->max_proto.tcp.port != range->min_proto.tcp.port)
- printf("-%hu", ntohs(range->max_proto.tcp.port));
- if (rev >= 2 && (range->flags & NF_NAT_RANGE_PROTO_OFFSET))
- printf("/%hu", ntohs(range->base_proto.tcp.port));
- }
-}
-
-static void _DNAT_print(const struct nf_nat_range2 *range, int rev)
-{
- printf(" to:");
- print_range(range, rev);
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" random");
- if (range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" persistent");
-}
-
-static void DNAT_print(const void *ip, const struct xt_entry_target *target,
- int numeric)
-{
- const struct nf_nat_range *range_v1 = (const void *)target->data;
- struct nf_nat_range2 range = {};
-
- memcpy(&range, range_v1, sizeof(*range_v1));
- _DNAT_print(&range, 1);
-}
-
-static void DNAT_print_v2(const void *ip, const struct xt_entry_target *target,
- int numeric)
-{
- _DNAT_print((const struct nf_nat_range2 *)target->data, 2);
-}
-
-static void _DNAT_save(const struct nf_nat_range2 *range, int rev)
-{
- printf(" --to-destination ");
- print_range(range, rev);
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" --random");
- if (range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" --persistent");
-}
-
-static void DNAT_save(const void *ip, const struct xt_entry_target *target)
-{
- const struct nf_nat_range *range_v1 = (const void *)target->data;
- struct nf_nat_range2 range = {};
-
- memcpy(&range, range_v1, sizeof(*range_v1));
- _DNAT_save(&range, 1);
-}
-
-static void DNAT_save_v2(const void *ip, const struct xt_entry_target *target)
-{
- _DNAT_save((const struct nf_nat_range2 *)target->data, 2);
-}
-
-static void print_range_xlate(const struct nf_nat_range2 *range,
- struct xt_xlate *xl, int rev)
-{
- bool proto_specified = range->flags & NF_NAT_RANGE_PROTO_SPECIFIED;
-
- if (range->flags & NF_NAT_RANGE_MAP_IPS) {
- xt_xlate_add(xl, "%s%s%s",
- proto_specified ? "[" : "",
- xtables_ip6addr_to_numeric(&range->min_addr.in6),
- proto_specified ? "]" : "");
-
- if (memcmp(&range->min_addr, &range->max_addr,
- sizeof(range->min_addr))) {
- xt_xlate_add(xl, "-%s%s%s",
- proto_specified ? "[" : "",
- xtables_ip6addr_to_numeric(&range->max_addr.in6),
- proto_specified ? "]" : "");
- }
- }
- if (proto_specified) {
- xt_xlate_add(xl, ":%hu", ntohs(range->min_proto.tcp.port));
-
- if (range->max_proto.tcp.port != range->min_proto.tcp.port)
- xt_xlate_add(xl, "-%hu",
- ntohs(range->max_proto.tcp.port));
- }
-}
-
-static int _DNAT_xlate(struct xt_xlate *xl,
- const struct nf_nat_range2 *range, int rev)
-{
- bool sep_need = false;
- const char *sep = " ";
-
- xt_xlate_add(xl, "dnat to ");
- print_range_xlate(range, xl, rev);
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM) {
- xt_xlate_add(xl, " random");
- sep_need = true;
- }
- if (range->flags & NF_NAT_RANGE_PERSISTENT) {
- if (sep_need)
- sep = ",";
- xt_xlate_add(xl, "%spersistent", sep);
- }
-
- return 1;
-}
-
-static int DNAT_xlate(struct xt_xlate *xl,
- const struct xt_xlate_tg_params *params)
-{
- const struct nf_nat_range *range_v1 = (const void *)params->target->data;
- struct nf_nat_range2 range = {};
-
- memcpy(&range, range_v1, sizeof(*range_v1));
- _DNAT_xlate(xl, &range, 1);
-
- return 1;
-}
-
-static int DNAT_xlate_v2(struct xt_xlate *xl,
- const struct xt_xlate_tg_params *params)
-{
- _DNAT_xlate(xl, (const struct nf_nat_range2 *)params->target->data, 2);
-
- return 1;
-}
-
-static struct xtables_target dnat_tg_reg[] = {
- {
- .name = "DNAT",
- .version = XTABLES_VERSION,
- .family = NFPROTO_IPV6,
- .revision = 1,
- .size = XT_ALIGN(sizeof(struct nf_nat_range)),
- .userspacesize = XT_ALIGN(sizeof(struct nf_nat_range)),
- .help = DNAT_help,
- .print = DNAT_print,
- .save = DNAT_save,
- .x6_parse = DNAT_parse,
- .x6_fcheck = DNAT_fcheck,
- .x6_options = DNAT_opts,
- .xlate = DNAT_xlate,
- },
- {
- .name = "DNAT",
- .version = XTABLES_VERSION,
- .family = NFPROTO_IPV6,
- .revision = 2,
- .size = XT_ALIGN(sizeof(struct nf_nat_range2)),
- .userspacesize = XT_ALIGN(sizeof(struct nf_nat_range2)),
- .help = DNAT_help_v2,
- .print = DNAT_print_v2,
- .save = DNAT_save_v2,
- .x6_parse = DNAT_parse_v2,
- .x6_fcheck = DNAT_fcheck_v2,
- .x6_options = DNAT_opts,
- .xlate = DNAT_xlate_v2,
- },
-};
-
-void _init(void)
-{
- xtables_register_targets(dnat_tg_reg, ARRAY_SIZE(dnat_tg_reg));
-}
diff --git a/extensions/libip6t_DNAT.txlate b/extensions/libip6t_DNAT.txlate
deleted file mode 100644
index 03c4caf7e87c4..0000000000000
--- a/extensions/libip6t_DNAT.txlate
+++ /dev/null
@@ -1,11 +0,0 @@
-ip6tables-translate -t nat -A prerouting -i eth1 -p tcp --dport 8080 -j DNAT --to-destination [fec0::1234]:80
-nft add rule ip6 nat prerouting iifname "eth1" tcp dport 8080 counter dnat to [fec0::1234]:80
-
-ip6tables-translate -t nat -A prerouting -p tcp -j DNAT --to-destination [fec0::1234]:1-20
-nft add rule ip6 nat prerouting meta l4proto tcp counter dnat to [fec0::1234]:1-20
-
-ip6tables-translate -t nat -A prerouting -p tcp -j DNAT --to-destination [fec0::1234]:80 --persistent
-nft add rule ip6 nat prerouting meta l4proto tcp counter dnat to [fec0::1234]:80 persistent
-
-ip6tables-translate -t nat -A prerouting -p tcp -j DNAT --to-destination [fec0::1234]:80 --random --persistent
-nft add rule ip6 nat prerouting meta l4proto tcp counter dnat to [fec0::1234]:80 random,persistent
diff --git a/extensions/libipt_DNAT.txlate b/extensions/libipt_DNAT.txlate
deleted file mode 100644
index e88314d9dba59..0000000000000
--- a/extensions/libipt_DNAT.txlate
+++ /dev/null
@@ -1,14 +0,0 @@
-iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4
-nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4
-
-iptables-translate -t nat -A prerouting -p tcp -d 15.45.23.67 --dport 80 -j DNAT --to-destination 192.168.1.1-192.168.1.10
-nft add rule ip nat prerouting ip daddr 15.45.23.67 tcp dport 80 counter dnat to 192.168.1.1-192.168.1.10
-
-iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4:1-1023
-nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4:1-1023
-
-iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4 --random
-nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4 random
-
-iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4 --random --persistent
-nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4 random,persistent
diff --git a/extensions/libxt_DNAT.c b/extensions/libxt_DNAT.c
index 9a179919f522d..83ff95b0013c7 100644
--- a/extensions/libxt_DNAT.c
+++ b/extensions/libxt_DNAT.c
@@ -1,3 +1,10 @@
+/*
+ * Copyright (c) 2011 Patrick McHardy <kaber@trash.net>
+ *
+ * Based on Rusty Russell's IPv4 DNAT target. Development of IPv6 NAT
+ * funded by Astaro.
+ */
+
#include <stdio.h>
#include <netdb.h>
#include <string.h>
@@ -7,6 +14,7 @@
#include <limits.h> /* INT_MAX in ip_tables.h */
#include <arpa/inet.h>
#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter/nf_nat.h>
#define TO_IPV4_MRC(ptr) ((const struct nf_nat_ipv4_multi_range_compat *)(ptr))
@@ -119,18 +127,36 @@ parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
/* Ranges expected in network order. */
static void
-parse_to(const char *orig_arg, bool portok, struct nf_nat_range2 *range)
+parse_to(const char *orig_arg, bool portok,
+ struct nf_nat_range2 *range, int family)
{
- char *arg, *colon, *dash;
+ char *arg, *start, *end, *colon, *dash;
arg = xtables_strdup(orig_arg);
- colon = strchr(arg, ':');
+ start = strchr(arg, '[');
+ if (!start) {
+ start = arg;
+ /* Lets assume one colon is port information.
+ * Otherwise its an IPv6 address */
+ colon = strchr(arg, ':');
+ if (colon && strchr(colon + 1, ':'))
+ colon = NULL;
+ } else {
+ start++;
+ end = strchr(start, ']');
+ if (end == NULL || family == AF_INET)
+ xtables_error(PARAMETER_PROBLEM,
+ "Invalid address format");
+
+ *end = '\0';
+ colon = strchr(end + 1, ':');
+ }
if (colon) {
parse_ports(colon + 1, portok, range);
- /* Starts with a colon? No IP info...*/
- if (colon == arg) {
+ /* Starts with colon or [] colon? No IP info...*/
+ if (colon == arg || colon == arg + 2) {
free(arg);
return;
}
@@ -138,20 +164,20 @@ parse_to(const char *orig_arg, bool portok, struct nf_nat_range2 *range)
}
range->flags |= NF_NAT_RANGE_MAP_IPS;
- dash = strchr(arg, '-');
+ dash = strchr(start, '-');
if (colon && dash && dash > colon)
dash = NULL;
if (dash)
*dash = '\0';
- if (!inet_pton(AF_INET, arg, &range->min_addr))
+ if (!inet_pton(family, start, &range->min_addr))
xtables_error(PARAMETER_PROBLEM,
- "Bad IP address \"%s\"\n", arg);
+ "Bad IP address \"%s\"", arg);
if (dash) {
- if (!inet_pton(AF_INET, dash + 1, &range->max_addr))
+ if (!inet_pton(family, dash + 1, &range->max_addr))
xtables_error(PARAMETER_PROBLEM,
- "Bad IP address \"%s\"\n", dash + 1);
+ "Bad IP address \"%s\"", dash + 1);
} else {
range->max_addr = range->min_addr;
}
@@ -160,7 +186,7 @@ parse_to(const char *orig_arg, bool portok, struct nf_nat_range2 *range)
}
static void __DNAT_parse(struct xt_option_call *cb, __u16 proto,
- struct nf_nat_range2 *range)
+ struct nf_nat_range2 *range, int family)
{
bool portok = proto == IPPROTO_TCP ||
proto == IPPROTO_UDP ||
@@ -171,7 +197,7 @@ static void __DNAT_parse(struct xt_option_call *cb, __u16 proto,
xtables_option_parse(cb);
switch (cb->entry->id) {
case O_TO_DEST:
- parse_to(cb->arg, portok, range);
+ parse_to(cb->arg, portok, range, family);
break;
case O_PERSISTENT:
range->flags |= NF_NAT_RANGE_PERSISTENT;
@@ -185,7 +211,7 @@ static void DNAT_parse(struct xt_option_call *cb)
const struct ipt_entry *entry = cb->xt_entry;
struct nf_nat_range2 range = {};
- __DNAT_parse(cb, entry->ip.proto, &range);
+ __DNAT_parse(cb, entry->ip.proto, &range, AF_INET);
switch (cb->entry->id) {
case O_TO_DEST:
@@ -200,32 +226,45 @@ static void DNAT_parse(struct xt_option_call *cb)
}
}
-static void DNAT_fcheck(struct xt_fcheck_call *cb)
+static void __DNAT_fcheck(struct xt_fcheck_call *cb, unsigned int *flags)
{
static const unsigned int f = F_TO_DEST | F_RANDOM;
- struct nf_nat_ipv4_multi_range_compat *mr = cb->data;
if ((cb->xflags & f) == f)
- mr->range[0].flags |= NF_NAT_RANGE_PROTO_RANDOM;
+ *flags |= NF_NAT_RANGE_PROTO_RANDOM;
+}
+
+static void DNAT_fcheck(struct xt_fcheck_call *cb)
+{
+ struct nf_nat_ipv4_multi_range_compat *mr = cb->data;
mr->rangesize = 1;
if (mr->range[0].flags & NF_NAT_RANGE_PROTO_OFFSET)
xtables_error(PARAMETER_PROBLEM,
"Shifted portmap ranges not supported with this kernel");
+
+ __DNAT_fcheck(cb, &mr->range[0].flags);
}
-static char *sprint_range(const struct nf_nat_range2 *r)
+static char *sprint_range(const struct nf_nat_range2 *r, int family)
{
- static char buf[INET_ADDRSTRLEN * 2 + 1 + 6 * 3];
+ bool brackets = family == AF_INET6 &&
+ r->flags & NF_NAT_RANGE_PROTO_SPECIFIED;
+ static char buf[INET6_ADDRSTRLEN * 2 + 3 + 6 * 3] = "";
if (r->flags & NF_NAT_RANGE_MAP_IPS) {
- sprintf(buf, "%s", xtables_ipaddr_to_numeric(&r->min_addr.in));
- if (memcmp(&r->min_addr, &r->max_addr, sizeof(r->min_addr)))
- sprintf(buf + strlen(buf), "-%s",
- xtables_ipaddr_to_numeric(&r->max_addr.in));
- } else {
- buf[0] = '\0';
+ if (brackets)
+ strcat(buf, "[");
+ inet_ntop(family, &r->min_addr,
+ buf + strlen(buf), INET6_ADDRSTRLEN);
+ if (memcmp(&r->min_addr, &r->max_addr, sizeof(r->min_addr))) {
+ strcat(buf, "-");
+ inet_ntop(family, &r->max_addr,
+ buf + strlen(buf), INET6_ADDRSTRLEN);
+ }
+ if (brackets)
+ strcat(buf, "]");
}
if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
sprintf(buf + strlen(buf), ":%hu",
@@ -240,11 +279,12 @@ static char *sprint_range(const struct nf_nat_range2 *r)
return buf;
}
-static void __DNAT_print(const struct nf_nat_range2 *r, bool save)
+static void __DNAT_print(const struct nf_nat_range2 *r, bool save, int family)
{
const char *dashdash = save ? "--" : "";
- printf(" %s%s", save ? "--to-destination " : "to:", sprint_range(r));
+ printf(" %s%s", save ? "--to-destination " : "to:",
+ sprint_range(r, family));
if (r->flags & NF_NAT_RANGE_PROTO_RANDOM)
printf(" %srandom", dashdash);
if (r->flags & NF_NAT_RANGE_PERSISTENT)
@@ -256,19 +296,20 @@ static void DNAT_print(const void *ip, const struct xt_entry_target *target,
{
struct nf_nat_range2 range = RANGE2_INIT_FROM_IPV4_MRC(target->data);
- __DNAT_print(&range, false);
+ __DNAT_print(&range, false, AF_INET);
}
static void DNAT_save(const void *ip, const struct xt_entry_target *target)
{
struct nf_nat_range2 range = RANGE2_INIT_FROM_IPV4_MRC(target->data);
- __DNAT_print(&range, true);
+ __DNAT_print(&range, true, AF_INET);
}
-static int __DNAT_xlate(struct xt_xlate *xl, const struct nf_nat_range2 *r)
+static int
+__DNAT_xlate(struct xt_xlate *xl, const struct nf_nat_range2 *r, int family)
{
- char *range_str = sprint_range(r);
+ char *range_str = sprint_range(r, family);
const char *sep = " ";
/* shifted portmap ranges are not supported by nftables */
@@ -295,40 +336,109 @@ static int DNAT_xlate(struct xt_xlate *xl,
struct nf_nat_range2 range =
RANGE2_INIT_FROM_IPV4_MRC(params->target->data);
- return __DNAT_xlate(xl, &range);
+ return __DNAT_xlate(xl, &range, AF_INET);
}
static void DNAT_parse_v2(struct xt_option_call *cb)
{
const struct ipt_entry *entry = cb->xt_entry;
- __DNAT_parse(cb, entry->ip.proto, cb->data);
+ __DNAT_parse(cb, entry->ip.proto, cb->data, AF_INET);
}
static void DNAT_fcheck_v2(struct xt_fcheck_call *cb)
{
- static const unsigned int f = F_TO_DEST | F_RANDOM;
- struct nf_nat_range2 *range = cb->data;
-
- if ((cb->xflags & f) == f)
- range->flags |= NF_NAT_RANGE_PROTO_RANDOM;
+ __DNAT_fcheck(cb, &((struct nf_nat_range2 *)cb->data)->flags);
}
static void DNAT_print_v2(const void *ip, const struct xt_entry_target *target,
int numeric)
{
- __DNAT_print((const void *)target->data, false);
+ __DNAT_print((const void *)target->data, false, AF_INET);
}
static void DNAT_save_v2(const void *ip, const struct xt_entry_target *target)
{
- __DNAT_print((const void *)target->data, true);
+ __DNAT_print((const void *)target->data, true, AF_INET);
}
static int DNAT_xlate_v2(struct xt_xlate *xl,
- const struct xt_xlate_tg_params *params)
+ const struct xt_xlate_tg_params *params)
{
- return __DNAT_xlate(xl, (const void *)params->target->data);
+ return __DNAT_xlate(xl, (const void *)params->target->data, AF_INET);
+}
+
+static void DNAT_parse6(struct xt_option_call *cb)
+{
+ const struct ip6t_entry *entry = cb->xt_entry;
+ struct nf_nat_range *range_v1 = (void *)cb->data;
+ struct nf_nat_range2 range = {};
+
+ memcpy(&range, range_v1, sizeof(*range_v1));
+ __DNAT_parse(cb, entry->ipv6.proto, &range, AF_INET6);
+ memcpy(range_v1, &range, sizeof(*range_v1));
+}
+
+static void DNAT_fcheck6(struct xt_fcheck_call *cb)
+{
+ struct nf_nat_range *range = (void *)cb->data;
+
+ if (range->flags & NF_NAT_RANGE_PROTO_OFFSET)
+ xtables_error(PARAMETER_PROBLEM,
+ "Shifted portmap ranges not supported with this kernel");
+
+ __DNAT_fcheck(cb, &range->flags);
+}
+
+static void DNAT_print6(const void *ip, const struct xt_entry_target *target,
+ int numeric)
+{
+ struct nf_nat_range2 range = {};
+
+ memcpy(&range, (const void *)target->data, sizeof(struct nf_nat_range));
+ __DNAT_print(&range, true, AF_INET6);
+}
+
+static void DNAT_save6(const void *ip, const struct xt_entry_target *target)
+{
+ struct nf_nat_range2 range = {};
+
+ memcpy(&range, (const void *)target->data, sizeof(struct nf_nat_range));
+ __DNAT_print(&range, true, AF_INET6);
+}
+
+static int DNAT_xlate6(struct xt_xlate *xl,
+ const struct xt_xlate_tg_params *params)
+{
+ struct nf_nat_range2 range = {};
+
+ memcpy(&range, (const void *)params->target->data,
+ sizeof(struct nf_nat_range));
+ return __DNAT_xlate(xl, &range, AF_INET6);
+}
+
+static void DNAT_parse6_v2(struct xt_option_call *cb)
+{
+ const struct ip6t_entry *entry = cb->xt_entry;
+
+ __DNAT_parse(cb, entry->ipv6.proto, cb->data, AF_INET6);
+}
+
+static void DNAT_print6_v2(const void *ip, const struct xt_entry_target *target,
+ int numeric)
+{
+ __DNAT_print((const void *)target->data, true, AF_INET6);
+}
+
+static void DNAT_save6_v2(const void *ip, const struct xt_entry_target *target)
+{
+ __DNAT_print((const void *)target->data, true, AF_INET6);
+}
+
+static int DNAT_xlate6_v2(struct xt_xlate *xl,
+ const struct xt_xlate_tg_params *params)
+{
+ return __DNAT_xlate(xl, (const void *)params->target->data, AF_INET6);
}
static struct xtables_target dnat_tg_reg[] = {
@@ -347,6 +457,21 @@ static struct xtables_target dnat_tg_reg[] = {
.x6_options = DNAT_opts,
.xlate = DNAT_xlate,
},
+ {
+ .name = "DNAT",
+ .version = XTABLES_VERSION,
+ .family = NFPROTO_IPV6,
+ .revision = 1,
+ .size = XT_ALIGN(sizeof(struct nf_nat_range)),
+ .userspacesize = XT_ALIGN(sizeof(struct nf_nat_range)),
+ .help = DNAT_help,
+ .print = DNAT_print6,
+ .save = DNAT_save6,
+ .x6_parse = DNAT_parse6,
+ .x6_fcheck = DNAT_fcheck6,
+ .x6_options = DNAT_opts,
+ .xlate = DNAT_xlate6,
+ },
{
.name = "DNAT",
.version = XTABLES_VERSION,
@@ -362,6 +487,21 @@ static struct xtables_target dnat_tg_reg[] = {
.x6_options = DNAT_opts,
.xlate = DNAT_xlate_v2,
},
+ {
+ .name = "DNAT",
+ .version = XTABLES_VERSION,
+ .family = NFPROTO_IPV6,
+ .revision = 2,
+ .size = XT_ALIGN(sizeof(struct nf_nat_range2)),
+ .userspacesize = XT_ALIGN(sizeof(struct nf_nat_range2)),
+ .help = DNAT_help_v2,
+ .print = DNAT_print6_v2,
+ .save = DNAT_save6_v2,
+ .x6_parse = DNAT_parse6_v2,
+ .x6_fcheck = DNAT_fcheck_v2,
+ .x6_options = DNAT_opts,
+ .xlate = DNAT_xlate6_v2,
+ },
};
void _init(void)
diff --git a/extensions/libxt_DNAT.txlate b/extensions/libxt_DNAT.txlate
new file mode 100644
index 0000000000000..a65976562ef53
--- /dev/null
+++ b/extensions/libxt_DNAT.txlate
@@ -0,0 +1,35 @@
+iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4
+nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4
+
+iptables-translate -t nat -A prerouting -p tcp -d 15.45.23.67 --dport 80 -j DNAT --to-destination 192.168.1.1-192.168.1.10
+nft add rule ip nat prerouting ip daddr 15.45.23.67 tcp dport 80 counter dnat to 192.168.1.1-192.168.1.10
+
+iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4:1-1023
+nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4:1-1023
+
+iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4 --random
+nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4 random
+
+iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4 --random --persistent
+nft add rule ip nat prerouting oifname "eth0" ip protocol tcp counter dnat to 1.2.3.4 random,persistent
+
+ip6tables-translate -t nat -A prerouting -p tcp --dport 8080 -j DNAT --to-destination fec0::1234
+nft add rule ip6 nat prerouting tcp dport 8080 counter dnat to fec0::1234
+
+ip6tables-translate -t nat -A prerouting -p tcp --dport 8080 -j DNAT --to-destination fec0::1234-fec0::2000
+nft add rule ip6 nat prerouting tcp dport 8080 counter dnat to fec0::1234-fec0::2000
+
+ip6tables-translate -t nat -A prerouting -i eth1 -p tcp --dport 8080 -j DNAT --to-destination [fec0::1234]:80
+nft add rule ip6 nat prerouting iifname "eth1" tcp dport 8080 counter dnat to [fec0::1234]:80
+
+ip6tables-translate -t nat -A prerouting -p tcp -j DNAT --to-destination [fec0::1234]:1-20
+nft add rule ip6 nat prerouting meta l4proto tcp counter dnat to [fec0::1234]:1-20
+
+ip6tables-translate -t nat -A prerouting -p tcp -j DNAT --to-destination [fec0::1234-fec0::2000]:1-20
+nft add rule ip6 nat prerouting meta l4proto tcp counter dnat to [fec0::1234-fec0::2000]:1-20
+
+ip6tables-translate -t nat -A prerouting -p tcp -j DNAT --to-destination [fec0::1234]:80 --persistent
+nft add rule ip6 nat prerouting meta l4proto tcp counter dnat to [fec0::1234]:80 persistent
+
+ip6tables-translate -t nat -A prerouting -p tcp -j DNAT --to-destination [fec0::1234]:80 --random --persistent
+nft add rule ip6 nat prerouting meta l4proto tcp counter dnat to [fec0::1234]:80 random,persistent
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [iptables PATCH 8/9] extensions: Merge REDIRECT into DNAT
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
` (6 preceding siblings ...)
2022-03-30 15:58 ` [iptables PATCH 7/9] extensions: Merge IPv4 and IPv6 DNAT targets Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 15:58 ` [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots Phil Sutter
8 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
Code is very similar, join them to reuse parsing code at least.
As a side-effect, this enables parsing of service names for ports in
DNAT.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/GNUmakefile.in | 4 +-
extensions/libip6t_REDIRECT.c | 170 ----------------------------
extensions/libip6t_REDIRECT.t | 6 -
extensions/libip6t_REDIRECT.txlate | 5 -
extensions/libipt_DNAT.t | 2 +
extensions/libipt_REDIRECT.c | 174 -----------------------------
extensions/libipt_REDIRECT.t | 6 -
extensions/libipt_REDIRECT.txlate | 5 -
extensions/libxt_DNAT.c | 169 +++++++++++++++++++++++++---
extensions/libxt_REDIRECT.t | 9 ++
extensions/libxt_REDIRECT.txlate | 17 +++
11 files changed, 186 insertions(+), 381 deletions(-)
delete mode 100644 extensions/libip6t_REDIRECT.c
delete mode 100644 extensions/libip6t_REDIRECT.t
delete mode 100644 extensions/libip6t_REDIRECT.txlate
delete mode 100644 extensions/libipt_REDIRECT.c
delete mode 100644 extensions/libipt_REDIRECT.t
delete mode 100644 extensions/libipt_REDIRECT.txlate
create mode 100644 extensions/libxt_REDIRECT.t
create mode 100644 extensions/libxt_REDIRECT.txlate
diff --git a/extensions/GNUmakefile.in b/extensions/GNUmakefile.in
index 956ccb38b2ab9..6dad4e02481bd 100644
--- a/extensions/GNUmakefile.in
+++ b/extensions/GNUmakefile.in
@@ -42,7 +42,7 @@ endif
pfx_build_mod := $(patsubst ${srcdir}/libxt_%.c,%,$(sort $(wildcard ${srcdir}/libxt_*.c)))
@ENABLE_NFTABLES_TRUE@ pfb_build_mod := $(patsubst ${srcdir}/libebt_%.c,%,$(sort $(wildcard ${srcdir}/libebt_*.c)))
@ENABLE_NFTABLES_TRUE@ pfa_build_mod := $(patsubst ${srcdir}/libarpt_%.c,%,$(sort $(wildcard ${srcdir}/libarpt_*.c)))
-pfx_symlinks := NOTRACK state
+pfx_symlinks := NOTRACK state REDIRECT
@ENABLE_IPV4_TRUE@ pf4_build_mod := $(patsubst ${srcdir}/libipt_%.c,%,$(sort $(wildcard ${srcdir}/libipt_*.c)))
@ENABLE_IPV6_TRUE@ pf6_build_mod := $(patsubst ${srcdir}/libip6t_%.c,%,$(sort $(wildcard ${srcdir}/libip6t_*.c)))
pfx_build_mod := $(filter-out @blacklist_modules@ @blacklist_x_modules@,${pfx_build_mod})
@@ -130,6 +130,8 @@ libxt_NOTRACK.so: libxt_CT.so
ln -fs $< $@
libxt_state.so: libxt_conntrack.so
ln -fs $< $@
+libxt_REDIRECT.so: libxt_DNAT.so
+ ln -fs $< $@
# Need the LIBADDs in iptables/Makefile.am too for libxtables_la_LIBADD
xt_RATEEST_LIBADD = -lm
diff --git a/extensions/libip6t_REDIRECT.c b/extensions/libip6t_REDIRECT.c
deleted file mode 100644
index 8e04d2cd33d50..0000000000000
--- a/extensions/libip6t_REDIRECT.c
+++ /dev/null
@@ -1,170 +0,0 @@
-/*
- * Copyright (c) 2011 Patrick McHardy <kaber@trash.net>
- *
- * Based on Rusty Russell's IPv4 REDIRECT target. Development of IPv6 NAT
- * funded by Astaro.
- */
-
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <xtables.h>
-#include <limits.h> /* INT_MAX in ip_tables.h */
-#include <linux/netfilter_ipv6/ip6_tables.h>
-#include <linux/netfilter/nf_nat.h>
-
-enum {
- O_TO_PORTS = 0,
- O_RANDOM,
- F_TO_PORTS = 1 << O_TO_PORTS,
- F_RANDOM = 1 << O_RANDOM,
-};
-
-static void REDIRECT_help(void)
-{
- printf(
-"REDIRECT target options:\n"
-" --to-ports <port>[-<port>]\n"
-" Port (range) to map to.\n"
-" [--random]\n");
-}
-
-static const struct xt_option_entry REDIRECT_opts[] = {
- {.name = "to-ports", .id = O_TO_PORTS, .type = XTTYPE_STRING},
- {.name = "random", .id = O_RANDOM, .type = XTTYPE_NONE},
- XTOPT_TABLEEND,
-};
-
-/* Parses ports */
-static void
-parse_ports(const char *arg, struct nf_nat_range *range)
-{
- char *end = "";
- unsigned int port, maxport;
-
- range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
-
- if (!xtables_strtoui(arg, &end, &port, 0, UINT16_MAX) &&
- (port = xtables_service_to_port(arg, NULL)) == (unsigned)-1)
- xtables_param_act(XTF_BAD_VALUE, "REDIRECT", "--to-ports", arg);
-
- switch (*end) {
- case '\0':
- range->min_proto.tcp.port
- = range->max_proto.tcp.port
- = htons(port);
- return;
- case '-':
- if (!xtables_strtoui(end + 1, NULL, &maxport, 0, UINT16_MAX) &&
- (maxport = xtables_service_to_port(end + 1, NULL)) == (unsigned)-1)
- break;
-
- if (maxport < port)
- break;
-
- range->min_proto.tcp.port = htons(port);
- range->max_proto.tcp.port = htons(maxport);
- return;
- default:
- break;
- }
- xtables_param_act(XTF_BAD_VALUE, "REDIRECT", "--to-ports", arg);
-}
-
-static void REDIRECT_parse(struct xt_option_call *cb)
-{
- const struct ip6t_entry *entry = cb->xt_entry;
- struct nf_nat_range *range = (void *)(*cb->target)->data;
- int portok;
-
- if (entry->ipv6.proto == IPPROTO_TCP
- || entry->ipv6.proto == IPPROTO_UDP
- || entry->ipv6.proto == IPPROTO_SCTP
- || entry->ipv6.proto == IPPROTO_DCCP
- || entry->ipv6.proto == IPPROTO_ICMP)
- portok = 1;
- else
- portok = 0;
-
- xtables_option_parse(cb);
- switch (cb->entry->id) {
- case O_TO_PORTS:
- if (!portok)
- xtables_error(PARAMETER_PROBLEM,
- "Need TCP, UDP, SCTP or DCCP with port specification");
- parse_ports(cb->arg, range);
- if (cb->xflags & F_RANDOM)
- range->flags |= NF_NAT_RANGE_PROTO_RANDOM;
- break;
- case O_RANDOM:
- if (cb->xflags & F_TO_PORTS)
- range->flags |= NF_NAT_RANGE_PROTO_RANDOM;
- break;
- }
-}
-
-static void REDIRECT_print(const void *ip, const struct xt_entry_target *target,
- int numeric)
-{
- const struct nf_nat_range *range = (const void *)target->data;
-
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- printf(" redir ports ");
- printf("%hu", ntohs(range->min_proto.tcp.port));
- if (range->max_proto.tcp.port != range->min_proto.tcp.port)
- printf("-%hu", ntohs(range->max_proto.tcp.port));
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" random");
- }
-}
-
-static void REDIRECT_save(const void *ip, const struct xt_entry_target *target)
-{
- const struct nf_nat_range *range = (const void *)target->data;
-
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- printf(" --to-ports ");
- printf("%hu", ntohs(range->min_proto.tcp.port));
- if (range->max_proto.tcp.port != range->min_proto.tcp.port)
- printf("-%hu", ntohs(range->max_proto.tcp.port));
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" --random");
- }
-}
-
-static int REDIRECT_xlate(struct xt_xlate *xl,
- const struct xt_xlate_tg_params *params)
-{
- const struct nf_nat_range *range = (const void *)params->target->data;
-
- if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- xt_xlate_add(xl, "redirect to :%hu",
- ntohs(range->min_proto.tcp.port));
- if (range->max_proto.tcp.port != range->min_proto.tcp.port)
- xt_xlate_add(xl, "-%hu ",
- ntohs(range->max_proto.tcp.port));
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- xt_xlate_add(xl, " random ");
- }
-
- return 1;
-}
-
-static struct xtables_target redirect_tg_reg = {
- .name = "REDIRECT",
- .version = XTABLES_VERSION,
- .family = NFPROTO_IPV6,
- .size = XT_ALIGN(sizeof(struct nf_nat_range)),
- .userspacesize = XT_ALIGN(sizeof(struct nf_nat_range)),
- .help = REDIRECT_help,
- .x6_parse = REDIRECT_parse,
- .print = REDIRECT_print,
- .save = REDIRECT_save,
- .x6_options = REDIRECT_opts,
- .xlate = REDIRECT_xlate,
-};
-
-void _init(void)
-{
- xtables_register_target(&redirect_tg_reg);
-}
diff --git a/extensions/libip6t_REDIRECT.t b/extensions/libip6t_REDIRECT.t
deleted file mode 100644
index a0fb0ed19a5ea..0000000000000
--- a/extensions/libip6t_REDIRECT.t
+++ /dev/null
@@ -1,6 +0,0 @@
-:PREROUTING,OUTPUT
-*nat
--p tcp -j REDIRECT --to-ports 42;=;OK
--p udp -j REDIRECT --to-ports 42-1234;=;OK
--p tcp -j REDIRECT --to-ports 42-1234 --random;=;OK
--j REDIRECT --to-ports 42;;FAIL
diff --git a/extensions/libip6t_REDIRECT.txlate b/extensions/libip6t_REDIRECT.txlate
deleted file mode 100644
index 209f67a4235f9..0000000000000
--- a/extensions/libip6t_REDIRECT.txlate
+++ /dev/null
@@ -1,5 +0,0 @@
-ip6tables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080
-nft add rule ip6 nat prerouting tcp dport 80 counter redirect to :8080
-
-ip6tables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080 --random
-nft add rule ip6 nat prerouting tcp dport 80 counter redirect to :8080 random
diff --git a/extensions/libipt_DNAT.t b/extensions/libipt_DNAT.t
index 1c4413b9b3bb5..eb187bc91053b 100644
--- a/extensions/libipt_DNAT.t
+++ b/extensions/libipt_DNAT.t
@@ -13,4 +13,6 @@
-p tcp -j DNAT --to-destination 1.1.1.1:1000-2000/65535;=;OK
-p tcp -j DNAT --to-destination 1.1.1.1:1000-2000/0;;FAIL
-p tcp -j DNAT --to-destination 1.1.1.1:1000-2000/65536;;FAIL
+-p tcp -j DNAT --to-destination 1.1.1.1:ssh;-p tcp -j DNAT --to-destination 1.1.1.1:22;OK
+-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data;-p tcp -j DNAT --to-destination 1.1.1.1:20;OK
-j DNAT;;FAIL
diff --git a/extensions/libipt_REDIRECT.c b/extensions/libipt_REDIRECT.c
deleted file mode 100644
index 7850306f5fe25..0000000000000
--- a/extensions/libipt_REDIRECT.c
+++ /dev/null
@@ -1,174 +0,0 @@
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <xtables.h>
-#include <limits.h> /* INT_MAX in ip_tables.h */
-#include <linux/netfilter_ipv4/ip_tables.h>
-#include <linux/netfilter/nf_nat.h>
-
-enum {
- O_TO_PORTS = 0,
- O_RANDOM,
- F_TO_PORTS = 1 << O_TO_PORTS,
- F_RANDOM = 1 << O_RANDOM,
-};
-
-static void REDIRECT_help(void)
-{
- printf(
-"REDIRECT target options:\n"
-" --to-ports <port>[-<port>]\n"
-" Port (range) to map to.\n"
-" [--random]\n");
-}
-
-static const struct xt_option_entry REDIRECT_opts[] = {
- {.name = "to-ports", .id = O_TO_PORTS, .type = XTTYPE_STRING},
- {.name = "random", .id = O_RANDOM, .type = XTTYPE_NONE},
- XTOPT_TABLEEND,
-};
-
-static void REDIRECT_init(struct xt_entry_target *t)
-{
- struct nf_nat_ipv4_multi_range_compat *mr = (struct nf_nat_ipv4_multi_range_compat *)t->data;
-
- /* Actually, it's 0, but it's ignored at the moment. */
- mr->rangesize = 1;
-}
-
-/* Parses ports */
-static void
-parse_ports(const char *arg, struct nf_nat_ipv4_multi_range_compat *mr)
-{
- char *end = "";
- unsigned int port, maxport;
-
- mr->range[0].flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
-
- if (!xtables_strtoui(arg, &end, &port, 0, UINT16_MAX) &&
- (port = xtables_service_to_port(arg, NULL)) == (unsigned)-1)
- xtables_param_act(XTF_BAD_VALUE, "REDIRECT", "--to-ports", arg);
-
- switch (*end) {
- case '\0':
- mr->range[0].min.tcp.port
- = mr->range[0].max.tcp.port
- = htons(port);
- return;
- case '-':
- if (!xtables_strtoui(end + 1, NULL, &maxport, 0, UINT16_MAX) &&
- (maxport = xtables_service_to_port(end + 1, NULL)) == (unsigned)-1)
- break;
-
- if (maxport < port)
- break;
-
- mr->range[0].min.tcp.port = htons(port);
- mr->range[0].max.tcp.port = htons(maxport);
- return;
- default:
- break;
- }
- xtables_param_act(XTF_BAD_VALUE, "REDIRECT", "--to-ports", arg);
-}
-
-static void REDIRECT_parse(struct xt_option_call *cb)
-{
- const struct ipt_entry *entry = cb->xt_entry;
- struct nf_nat_ipv4_multi_range_compat *mr = (void *)(*cb->target)->data;
- int portok;
-
- if (entry->ip.proto == IPPROTO_TCP
- || entry->ip.proto == IPPROTO_UDP
- || entry->ip.proto == IPPROTO_SCTP
- || entry->ip.proto == IPPROTO_DCCP
- || entry->ip.proto == IPPROTO_ICMP)
- portok = 1;
- else
- portok = 0;
-
- xtables_option_parse(cb);
- switch (cb->entry->id) {
- case O_TO_PORTS:
- if (!portok)
- xtables_error(PARAMETER_PROBLEM,
- "Need TCP, UDP, SCTP or DCCP with port specification");
- parse_ports(cb->arg, mr);
- if (cb->xflags & F_RANDOM)
- mr->range[0].flags |= NF_NAT_RANGE_PROTO_RANDOM;
- break;
- case O_RANDOM:
- if (cb->xflags & F_TO_PORTS)
- mr->range[0].flags |= NF_NAT_RANGE_PROTO_RANDOM;
- break;
- }
-}
-
-static void REDIRECT_print(const void *ip, const struct xt_entry_target *target,
- int numeric)
-{
- const struct nf_nat_ipv4_multi_range_compat *mr = (const void *)target->data;
- const struct nf_nat_ipv4_range *r = &mr->range[0];
-
- if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- printf(" redir ports ");
- printf("%hu", ntohs(r->min.tcp.port));
- if (r->max.tcp.port != r->min.tcp.port)
- printf("-%hu", ntohs(r->max.tcp.port));
- if (mr->range[0].flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" random");
- }
-}
-
-static void REDIRECT_save(const void *ip, const struct xt_entry_target *target)
-{
- const struct nf_nat_ipv4_multi_range_compat *mr = (const void *)target->data;
- const struct nf_nat_ipv4_range *r = &mr->range[0];
-
- if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- printf(" --to-ports ");
- printf("%hu", ntohs(r->min.tcp.port));
- if (r->max.tcp.port != r->min.tcp.port)
- printf("-%hu", ntohs(r->max.tcp.port));
- if (mr->range[0].flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" --random");
- }
-}
-
-static int REDIRECT_xlate(struct xt_xlate *xl,
- const struct xt_xlate_tg_params *params)
-{
- const struct nf_nat_ipv4_multi_range_compat *mr =
- (const void *)params->target->data;
- const struct nf_nat_ipv4_range *r = &mr->range[0];
-
- if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- xt_xlate_add(xl, "redirect to :%hu", ntohs(r->min.tcp.port));
- if (r->max.tcp.port != r->min.tcp.port)
- xt_xlate_add(xl, "-%hu ", ntohs(r->max.tcp.port));
- if (mr->range[0].flags & NF_NAT_RANGE_PROTO_RANDOM)
- xt_xlate_add(xl, " random ");
- }
-
- return 1;
-}
-
-static struct xtables_target redirect_tg_reg = {
- .name = "REDIRECT",
- .version = XTABLES_VERSION,
- .family = NFPROTO_IPV4,
- .size = XT_ALIGN(sizeof(struct nf_nat_ipv4_multi_range_compat)),
- .userspacesize = XT_ALIGN(sizeof(struct nf_nat_ipv4_multi_range_compat)),
- .help = REDIRECT_help,
- .init = REDIRECT_init,
- .x6_parse = REDIRECT_parse,
- .print = REDIRECT_print,
- .save = REDIRECT_save,
- .x6_options = REDIRECT_opts,
- .xlate = REDIRECT_xlate,
-};
-
-void _init(void)
-{
- xtables_register_target(&redirect_tg_reg);
-}
diff --git a/extensions/libipt_REDIRECT.t b/extensions/libipt_REDIRECT.t
deleted file mode 100644
index a0fb0ed19a5ea..0000000000000
--- a/extensions/libipt_REDIRECT.t
+++ /dev/null
@@ -1,6 +0,0 @@
-:PREROUTING,OUTPUT
-*nat
--p tcp -j REDIRECT --to-ports 42;=;OK
--p udp -j REDIRECT --to-ports 42-1234;=;OK
--p tcp -j REDIRECT --to-ports 42-1234 --random;=;OK
--j REDIRECT --to-ports 42;;FAIL
diff --git a/extensions/libipt_REDIRECT.txlate b/extensions/libipt_REDIRECT.txlate
deleted file mode 100644
index 815bb7714138d..0000000000000
--- a/extensions/libipt_REDIRECT.txlate
+++ /dev/null
@@ -1,5 +0,0 @@
-iptables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080
-nft add rule ip nat prerouting tcp dport 80 counter redirect to :8080
-
-iptables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080 --random
-nft add rule ip nat prerouting tcp dport 80 counter redirect to :8080 random
diff --git a/extensions/libxt_DNAT.c b/extensions/libxt_DNAT.c
index 83ff95b0013c7..754e244e0dbe6 100644
--- a/extensions/libxt_DNAT.c
+++ b/extensions/libxt_DNAT.c
@@ -28,10 +28,12 @@
enum {
O_TO_DEST = 0,
+ O_TO_PORTS,
O_RANDOM,
O_PERSISTENT,
- F_TO_DEST = 1 << O_TO_DEST,
- F_RANDOM = 1 << O_RANDOM,
+ F_TO_DEST = 1 << O_TO_DEST,
+ F_TO_PORTS = 1 << O_TO_PORTS,
+ F_RANDOM = 1 << O_RANDOM,
};
static void DNAT_help(void)
@@ -52,6 +54,15 @@ static void DNAT_help_v2(void)
"[--random] [--persistent]\n");
}
+static void REDIRECT_help(void)
+{
+ printf(
+"REDIRECT target options:\n"
+" --to-ports <port>[-<port>]\n"
+" Port (range) to map to.\n"
+" [--random]\n");
+}
+
static const struct xt_option_entry DNAT_opts[] = {
{.name = "to-destination", .id = O_TO_DEST, .type = XTTYPE_STRING,
.flags = XTOPT_MAND},
@@ -60,6 +71,12 @@ static const struct xt_option_entry DNAT_opts[] = {
XTOPT_TABLEEND,
};
+static const struct xt_option_entry REDIRECT_opts[] = {
+ {.name = "to-ports", .id = O_TO_PORTS, .type = XTTYPE_STRING},
+ {.name = "random", .id = O_RANDOM, .type = XTTYPE_NONE},
+ XTOPT_TABLEEND,
+};
+
/* Parses ports */
static void
parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
@@ -73,9 +90,12 @@ parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
- if (!xtables_strtoui(arg, &end, &port, 1, UINT16_MAX))
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid", arg);
+ if (!xtables_strtoui(arg, &end, &port, 1, UINT16_MAX)) {
+ port = xtables_service_to_port(arg, NULL);
+ if (port == (unsigned)-1)
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
+ }
switch (*end) {
case '\0':
@@ -94,10 +114,12 @@ parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
"Garbage after port value: `%s'", end);
}
- if (!xtables_strtoui(arg, &end, &maxport, 1, UINT16_MAX))
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid", arg);
-
+ if (!xtables_strtoui(arg, &end, &maxport, 1, UINT16_MAX)) {
+ maxport = xtables_service_to_port(arg, NULL);
+ if (maxport == (unsigned)-1)
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
+ }
if (maxport < port)
/* People are stupid. */
xtables_error(PARAMETER_PROBLEM,
@@ -117,9 +139,12 @@ parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
"Garbage after port range: `%s'", end);
}
- if (!xtables_strtoui(arg, &end, &baseport, 1, UINT16_MAX))
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid", arg);
+ if (!xtables_strtoui(arg, &end, &baseport, 1, UINT16_MAX)) {
+ baseport = xtables_service_to_port(arg, NULL);
+ if (baseport == (unsigned)-1)
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
+ }
range->flags |= NF_NAT_RANGE_PROTO_OFFSET;
range->base_proto.tcp.port = htons(baseport);
@@ -199,6 +224,9 @@ static void __DNAT_parse(struct xt_option_call *cb, __u16 proto,
case O_TO_DEST:
parse_to(cb->arg, portok, range, family);
break;
+ case O_TO_PORTS:
+ parse_ports(cb->arg, portok, range);
+ break;
case O_PERSISTENT:
range->flags |= NF_NAT_RANGE_PERSISTENT;
break;
@@ -217,6 +245,8 @@ static void DNAT_parse(struct xt_option_call *cb)
case O_TO_DEST:
mr->range->min_ip = range.min_addr.ip;
mr->range->max_ip = range.max_addr.ip;
+ /* fall through */
+ case O_TO_PORTS:
mr->range->min = range.min_proto;
mr->range->max = range.max_proto;
/* fall through */
@@ -228,9 +258,13 @@ static void DNAT_parse(struct xt_option_call *cb)
static void __DNAT_fcheck(struct xt_fcheck_call *cb, unsigned int *flags)
{
- static const unsigned int f = F_TO_DEST | F_RANDOM;
+ static const unsigned int redir_f = F_TO_PORTS | F_RANDOM;
+ static const unsigned int dnat_f = F_TO_DEST | F_RANDOM;
+
- if ((cb->xflags & f) == f)
+
+ if ((cb->xflags & redir_f) == redir_f ||
+ (cb->xflags & dnat_f) == dnat_f)
*flags |= NF_NAT_RANGE_PROTO_RANDOM;
}
@@ -441,6 +475,84 @@ static int DNAT_xlate6_v2(struct xt_xlate *xl,
return __DNAT_xlate(xl, (const void *)params->target->data, AF_INET6);
}
+static void __REDIRECT_print(const struct nf_nat_range2 *range, bool save)
+{
+ char *range_str = sprint_range(range, AF_INET);
+ const char *dashdash = save ? "--" : "";
+
+ if (strlen(range_str))
+ /* range_str starts with colon, skip over them */
+ printf(" %s %s", save ? "--to-ports" : "redir ports",
+ range_str + 1);
+ if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
+ printf(" %srandom", dashdash);
+}
+
+static int __REDIRECT_xlate(struct xt_xlate *xl,
+ const struct nf_nat_range2 *range)
+{
+ char *range_str = sprint_range(range, AF_INET);
+
+ xt_xlate_add(xl, "redirect");
+ if (strlen(range_str))
+ xt_xlate_add(xl, " to %s", range_str);
+ if (range->flags & NF_NAT_RANGE_PROTO_RANDOM)
+ xt_xlate_add(xl, " random");
+
+ return 1;
+}
+
+static void REDIRECT_print(const void *ip, const struct xt_entry_target *target,
+ int numeric)
+{
+ struct nf_nat_range2 range = RANGE2_INIT_FROM_IPV4_MRC(target->data);
+
+ __REDIRECT_print(&range, false);
+}
+
+static void REDIRECT_save(const void *ip, const struct xt_entry_target *target)
+{
+ struct nf_nat_range2 range = RANGE2_INIT_FROM_IPV4_MRC(target->data);
+
+ __REDIRECT_print(&range, true);
+}
+
+static int REDIRECT_xlate(struct xt_xlate *xl,
+ const struct xt_xlate_tg_params *params)
+{
+ struct nf_nat_range2 range =
+ RANGE2_INIT_FROM_IPV4_MRC(params->target->data);
+
+ return __REDIRECT_xlate(xl, &range);
+}
+
+static void REDIRECT_print6(const void *ip, const struct xt_entry_target *target,
+ int numeric)
+{
+ struct nf_nat_range2 range = {};
+
+ memcpy(&range, (const void *)target->data, sizeof(struct nf_nat_range));
+ __REDIRECT_print(&range, false);
+}
+
+static void REDIRECT_save6(const void *ip, const struct xt_entry_target *target)
+{
+ struct nf_nat_range2 range = {};
+
+ memcpy(&range, (const void *)target->data, sizeof(struct nf_nat_range));
+ __REDIRECT_print(&range, true);
+}
+
+static int REDIRECT_xlate6(struct xt_xlate *xl,
+ const struct xt_xlate_tg_params *params)
+{
+ struct nf_nat_range2 range = {};
+
+ memcpy(&range, (const void *)params->target->data,
+ sizeof(struct nf_nat_range));
+ return __REDIRECT_xlate(xl, &range);
+}
+
static struct xtables_target dnat_tg_reg[] = {
{
.name = "DNAT",
@@ -457,6 +569,21 @@ static struct xtables_target dnat_tg_reg[] = {
.x6_options = DNAT_opts,
.xlate = DNAT_xlate,
},
+ {
+ .name = "REDIRECT",
+ .version = XTABLES_VERSION,
+ .family = NFPROTO_IPV4,
+ .revision = 0,
+ .size = XT_ALIGN(sizeof(struct nf_nat_ipv4_multi_range_compat)),
+ .userspacesize = XT_ALIGN(sizeof(struct nf_nat_ipv4_multi_range_compat)),
+ .help = REDIRECT_help,
+ .print = REDIRECT_print,
+ .save = REDIRECT_save,
+ .x6_parse = DNAT_parse,
+ .x6_fcheck = DNAT_fcheck,
+ .x6_options = REDIRECT_opts,
+ .xlate = REDIRECT_xlate,
+ },
{
.name = "DNAT",
.version = XTABLES_VERSION,
@@ -472,6 +599,20 @@ static struct xtables_target dnat_tg_reg[] = {
.x6_options = DNAT_opts,
.xlate = DNAT_xlate6,
},
+ {
+ .name = "REDIRECT",
+ .version = XTABLES_VERSION,
+ .family = NFPROTO_IPV6,
+ .size = XT_ALIGN(sizeof(struct nf_nat_range)),
+ .userspacesize = XT_ALIGN(sizeof(struct nf_nat_range)),
+ .help = REDIRECT_help,
+ .print = REDIRECT_print6,
+ .save = REDIRECT_save6,
+ .x6_parse = DNAT_parse6,
+ .x6_fcheck = DNAT_fcheck6,
+ .x6_options = REDIRECT_opts,
+ .xlate = REDIRECT_xlate6,
+ },
{
.name = "DNAT",
.version = XTABLES_VERSION,
diff --git a/extensions/libxt_REDIRECT.t b/extensions/libxt_REDIRECT.t
new file mode 100644
index 0000000000000..3f0b8a6000445
--- /dev/null
+++ b/extensions/libxt_REDIRECT.t
@@ -0,0 +1,9 @@
+:PREROUTING,OUTPUT
+*nat
+-p tcp -j REDIRECT --to-ports 42;=;OK
+-p udp -j REDIRECT --to-ports 42-1234;=;OK
+-p tcp -j REDIRECT --to-ports 42-1234 --random;=;OK
+-p tcp -j REDIRECT --to-ports 42-1234/567;;FAIL
+-p tcp -j REDIRECT --to-ports ssh;-p tcp -j REDIRECT --to-ports 22;OK
+-p tcp -j REDIRECT --to-ports ftp-data;-p tcp -j REDIRECT --to-ports 20;OK
+-j REDIRECT --to-ports 42;;FAIL
diff --git a/extensions/libxt_REDIRECT.txlate b/extensions/libxt_REDIRECT.txlate
new file mode 100644
index 0000000000000..c7375c614f50a
--- /dev/null
+++ b/extensions/libxt_REDIRECT.txlate
@@ -0,0 +1,17 @@
+iptables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT
+nft add rule ip nat prerouting tcp dport 80 counter redirect
+
+iptables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080
+nft add rule ip nat prerouting tcp dport 80 counter redirect to :8080
+
+iptables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080 --random
+nft add rule ip nat prerouting tcp dport 80 counter redirect to :8080 random
+
+ip6tables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT
+nft add rule ip6 nat prerouting tcp dport 80 counter redirect
+
+ip6tables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080
+nft add rule ip6 nat prerouting tcp dport 80 counter redirect to :8080
+
+ip6tables-translate -t nat -A prerouting -p tcp --dport 80 -j REDIRECT --to-ports 8080 --random
+nft add rule ip6 nat prerouting tcp dport 80 counter redirect to :8080 random
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots
2022-03-30 15:58 [iptables PATCH 0/9] extensions: Merge *_DNAT and *_REDIRECT Phil Sutter
` (7 preceding siblings ...)
2022-03-30 15:58 ` [iptables PATCH 8/9] extensions: Merge REDIRECT into DNAT Phil Sutter
@ 2022-03-30 15:58 ` Phil Sutter
2022-03-30 18:38 ` Jan Engelhardt
8 siblings, 1 reply; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 15:58 UTC (permalink / raw)
To: Pablo Neira Ayuso; +Cc: netfilter-devel
When parsing (parts of) a port spec, if it doesn't start with a digit,
try to find the largest substring getservbyname() accepts.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
extensions/libipt_DNAT.t | 4 +++
extensions/libxt_DNAT.c | 70 +++++++++++++++++++++++++++----------
extensions/libxt_REDIRECT.t | 2 ++
3 files changed, 58 insertions(+), 18 deletions(-)
diff --git a/extensions/libipt_DNAT.t b/extensions/libipt_DNAT.t
index eb187bc91053b..c744dff3ec902 100644
--- a/extensions/libipt_DNAT.t
+++ b/extensions/libipt_DNAT.t
@@ -15,4 +15,8 @@
-p tcp -j DNAT --to-destination 1.1.1.1:1000-2000/65536;;FAIL
-p tcp -j DNAT --to-destination 1.1.1.1:ssh;-p tcp -j DNAT --to-destination 1.1.1.1:22;OK
-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data;-p tcp -j DNAT --to-destination 1.1.1.1:20;OK
+-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data-ssh;-p tcp -j DNAT --to-destination 1.1.1.1:20-22;OK
+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data;-p tcp -j DNAT --to-destination 1.1.1.1:7-20;OK
+-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data-ssh/echo;-p tcp -j DNAT --to-destination 1.1.1.1:20-22/7;OK
+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data/ssh;-p tcp -j DNAT --to-destination 1.1.1.1:7-20/22;OK
-j DNAT;;FAIL
diff --git a/extensions/libxt_DNAT.c b/extensions/libxt_DNAT.c
index 754e244e0dbe6..70d2823568c7d 100644
--- a/extensions/libxt_DNAT.c
+++ b/extensions/libxt_DNAT.c
@@ -77,6 +77,49 @@ static const struct xt_option_entry REDIRECT_opts[] = {
XTOPT_TABLEEND,
};
+static char *strrchrs(const char *s, const char *chrs)
+{
+ int i;
+
+ for (i = strlen(s) - 1; i >= 0; i--) {
+ if (strchr(chrs, s[i]))
+ return (char *)s + i;
+ }
+ return NULL;
+}
+
+static bool parse_port(const char *orig_s, char **end, unsigned int *value,
+ unsigned int min, unsigned int max)
+{
+ char *s, *pos;
+ int port;
+
+ if (xtables_strtoui(orig_s, end, value, min, max))
+ return true;
+
+ s = xtables_strdup(orig_s);
+ port = xtables_service_to_port(s, NULL);
+ if (port >= min && port <= max)
+ goto found;
+
+ pos = strrchrs(s, "-:/");
+ while (pos) {
+ *pos = '\0';
+ port = xtables_service_to_port(s, NULL);
+ if (port >= min && port <= max)
+ goto found;
+
+ pos = strrchrs(s, "-:/");
+ }
+ free(s);
+ return false;
+found:
+ *end = (char *)orig_s + strlen(s);
+ *value = port;
+ free(s);
+ return true;
+}
+
/* Parses ports */
static void
parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
@@ -90,12 +133,9 @@ parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
- if (!xtables_strtoui(arg, &end, &port, 1, UINT16_MAX)) {
- port = xtables_service_to_port(arg, NULL);
- if (port == (unsigned)-1)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid", arg);
- }
+ if (!parse_port(arg, &end, &port, 1, UINT16_MAX))
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
switch (*end) {
case '\0':
@@ -114,12 +154,9 @@ parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
"Garbage after port value: `%s'", end);
}
- if (!xtables_strtoui(arg, &end, &maxport, 1, UINT16_MAX)) {
- maxport = xtables_service_to_port(arg, NULL);
- if (maxport == (unsigned)-1)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid", arg);
- }
+ if (!parse_port(arg, &end, &maxport, 1, UINT16_MAX))
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
if (maxport < port)
/* People are stupid. */
xtables_error(PARAMETER_PROBLEM,
@@ -139,12 +176,9 @@ parse_ports(const char *arg, bool portok, struct nf_nat_range2 *range)
"Garbage after port range: `%s'", end);
}
- if (!xtables_strtoui(arg, &end, &baseport, 1, UINT16_MAX)) {
- baseport = xtables_service_to_port(arg, NULL);
- if (baseport == (unsigned)-1)
- xtables_error(PARAMETER_PROBLEM,
- "Port `%s' not valid", arg);
- }
+ if (!parse_port(arg, &end, &baseport, 1, UINT16_MAX))
+ xtables_error(PARAMETER_PROBLEM,
+ "Port `%s' not valid", arg);
range->flags |= NF_NAT_RANGE_PROTO_OFFSET;
range->base_proto.tcp.port = htons(baseport);
diff --git a/extensions/libxt_REDIRECT.t b/extensions/libxt_REDIRECT.t
index 3f0b8a6000445..a50ef257ec956 100644
--- a/extensions/libxt_REDIRECT.t
+++ b/extensions/libxt_REDIRECT.t
@@ -6,4 +6,6 @@
-p tcp -j REDIRECT --to-ports 42-1234/567;;FAIL
-p tcp -j REDIRECT --to-ports ssh;-p tcp -j REDIRECT --to-ports 22;OK
-p tcp -j REDIRECT --to-ports ftp-data;-p tcp -j REDIRECT --to-ports 20;OK
+-p tcp -j REDIRECT --to-ports ftp-data-ssh;-p tcp -j REDIRECT --to-ports 20-22;OK
+-p tcp -j REDIRECT --to-ports echo-ftp-data;-p tcp -j REDIRECT --to-ports 7-20;OK
-j REDIRECT --to-ports 42;;FAIL
--
2.34.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* Re: [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots
2022-03-30 15:58 ` [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots Phil Sutter
@ 2022-03-30 18:38 ` Jan Engelhardt
2022-03-30 20:57 ` Phil Sutter
0 siblings, 1 reply; 14+ messages in thread
From: Jan Engelhardt @ 2022-03-30 18:38 UTC (permalink / raw)
To: Phil Sutter; +Cc: Pablo Neira Ayuso, netfilter-devel
On Wednesday 2022-03-30 17:58, Phil Sutter wrote:
>When parsing (parts of) a port spec, if it doesn't start with a digit,
>try to find the largest substring getservbyname() accepts.
> -p tcp -j DNAT --to-destination 1.1.1.1:1000-2000/65536;;FAIL
> -p tcp -j DNAT --to-destination 1.1.1.1:ssh;-p tcp -j DNAT --to-destination 1.1.1.1:22;OK
> -p tcp -j DNAT --to-destination 1.1.1.1:ftp-data;-p tcp -j DNAT --to-destination 1.1.1.1:20;OK
>+-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data-ssh;-p tcp -j DNAT --to-destination 1.1.1.1:20-22;OK
>+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data;-p tcp -j DNAT --to-destination 1.1.1.1:7-20;OK
>+-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data-ssh/echo;-p tcp -j DNAT --to-destination 1.1.1.1:20-22/7;OK
>+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data/ssh;-p tcp -j DNAT --to-destination 1.1.1.1:7-20/22;OK
> -j DNAT;;FAIL
This looks dangerous. It is why I originally never allowed service names in
port ranges that use dash as the range character. a-b-c could mean a..b-c
today, and could mean a-b..c tomorrow, either because someone managed to
inject a-b into the service list.
The "solution" would be to use : as the range character, but that would require
a new --dport option for reasons of command-line compatibility.
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots
2022-03-30 18:38 ` Jan Engelhardt
@ 2022-03-30 20:57 ` Phil Sutter
2022-03-31 0:19 ` Jan Engelhardt
0 siblings, 1 reply; 14+ messages in thread
From: Phil Sutter @ 2022-03-30 20:57 UTC (permalink / raw)
To: Jan Engelhardt; +Cc: Pablo Neira Ayuso, netfilter-devel
Hi Jan,
On Wed, Mar 30, 2022 at 08:38:28PM +0200, Jan Engelhardt wrote:
>
> On Wednesday 2022-03-30 17:58, Phil Sutter wrote:
>
> >When parsing (parts of) a port spec, if it doesn't start with a digit,
> >try to find the largest substring getservbyname() accepts.
>
> > -p tcp -j DNAT --to-destination 1.1.1.1:1000-2000/65536;;FAIL
> > -p tcp -j DNAT --to-destination 1.1.1.1:ssh;-p tcp -j DNAT --to-destination 1.1.1.1:22;OK
> > -p tcp -j DNAT --to-destination 1.1.1.1:ftp-data;-p tcp -j DNAT --to-destination 1.1.1.1:20;OK
> >+-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data-ssh;-p tcp -j DNAT --to-destination 1.1.1.1:20-22;OK
> >+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data;-p tcp -j DNAT --to-destination 1.1.1.1:7-20;OK
> >+-p tcp -j DNAT --to-destination 1.1.1.1:ftp-data-ssh/echo;-p tcp -j DNAT --to-destination 1.1.1.1:20-22/7;OK
> >+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data/ssh;-p tcp -j DNAT --to-destination 1.1.1.1:7-20/22;OK
> > -j DNAT;;FAIL
>
> This looks dangerous. It is why I originally never allowed service names in
> port ranges that use dash as the range character. a-b-c could mean a..b-c
> today, and could mean a-b..c tomorrow, either because someone managed to
> inject a-b into the service list.
Yes, it is a rather sloppy solution. I could at least do a shortest
substring first search in addition to check if the input is ambiguous.
Guess if someone is able to manipulate /etc/services, any service names
are problematic, not just in ranges.
Another potential problem I didn't have in mind though is that 'a-b'
could mean [a; b] or [a-b] assuming that all three exist. But I haven't
found a valid example in my /etc/services, yet. :)
> The "solution" would be to use : as the range character, but that would require
> a new --dport option for reasons of command-line compatibility.
Well, we could allow both (a-b with numeric a and b only) and use it in
output only if non-numeric was requested.
Maybe also just limit service names in DNAT to non-ranges. I wanted to
write "like with REDIRECT before the merge", but it looks like it
accepted them as upper boundary, e.g. '10-ftp-data'.
Hmm. I also noticed my series drops support for port 0 from REDIRECT
which commit 84d758b3bc312 ("extensions: REDIRECT: fix --to-ports
parser") explicitly allowed.
Thanks, Phil
^ permalink raw reply [flat|nested] 14+ messages in thread* Re: [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots
2022-03-30 20:57 ` Phil Sutter
@ 2022-03-31 0:19 ` Jan Engelhardt
2022-03-31 10:04 ` Phil Sutter
0 siblings, 1 reply; 14+ messages in thread
From: Jan Engelhardt @ 2022-03-31 0:19 UTC (permalink / raw)
To: Phil Sutter; +Cc: Pablo Neira Ayuso, netfilter-devel
On Wednesday 2022-03-30 22:57, Phil Sutter wrote:
>> >+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data/ssh;-p tcp -j DNAT --to-destination 1.1.1.1:7-20/22;OK
>>
>> This looks dangerous. It is why I originally never allowed service names in
>> port ranges that use dash as the range character.
>
>Guess if someone is able to manipulate /etc/services, any service names
>are problematic, not just in ranges.
Well, pretty much anyone has a shot at manipulating this file. File a
port registration with IANA, and when your distro updates the file,
eventually there is a chance of messing up firewall configs,
worldwide.
Other than that, thanks to nsswitch, the service list can also be in
LDAP or so, and then all that's needed is a disgruntled LDAP admin
who dislikes the firewall admin.
>Another potential problem I didn't have in mind though is that 'a-b'
>could mean [a; b] or [a-b] assuming that all three exist. But I haven't
>found a valid example in my /etc/services, yet. :)
I found 25 at once!
914c :: 914c-g :: g-talk
ads :: ads-s :: s-openmail
bctp :: bctp-server :: server-find
cis :: cis-secure :: secure-mqtt
connect :: connect-server :: server-find
docker :: docker-s :: s-openmail
documentum :: documentum-s :: s-openmail
domain :: domain-s :: s-openmail
dtp :: dtp-net :: net-device
genie :: genie-lm :: lm-mon
linktest :: linktest-s :: s-openmail
mailbox :: mailbox-lm :: lm-mon
mbap :: mbap-s :: s-openmail
ns :: ns-server :: server-find
plato :: plato-lm :: lm-mon
rmonitor :: rmonitor-secure :: secure-mqtt
sentinel :: sentinel-lm :: lm-mon
sitewatch :: sitewatch-s :: s-openmail
spss :: spss-lm :: lm-mon
sql :: sql-net :: net-device
tacacs :: tacacs-ds :: ds-slp
tl1 :: tl1-lv :: lv-auth
trim :: trim-ice :: ice-router
wnn6 :: wnn6-ds :: ds-slp
wsdapi :: wsdapi-s :: s-openmail
To be read as: "wsdapi-s-openmail" is ambiguous, because
it allows for two interpretations (and all four port names are in
/etc/services):
[wsdapi]-[s-openmail]
[wsdapi-s]-[openmail]
>> The "solution" would be to use : as the range character, but that would require
>> a new --dport option for reasons of command-line compatibility.
>
>Well, we could allow both (a-b with numeric a and b only) and use it in
>output only if non-numeric was requested.
Given I'm seeing "914c" in the IANA list (leading digits always stand
out from the crowd, e.g. you don't normally see them in UNIX
usernames either), I won't hold my breath that no one would try to
register "914-915".
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [iptables PATCH 9/9] extensions: DNAT: Support service names in all spots
2022-03-31 0:19 ` Jan Engelhardt
@ 2022-03-31 10:04 ` Phil Sutter
0 siblings, 0 replies; 14+ messages in thread
From: Phil Sutter @ 2022-03-31 10:04 UTC (permalink / raw)
To: Jan Engelhardt; +Cc: Pablo Neira Ayuso, netfilter-devel
On Thu, Mar 31, 2022 at 02:19:51AM +0200, Jan Engelhardt wrote:
> On Wednesday 2022-03-30 22:57, Phil Sutter wrote:
> >> >+-p tcp -j DNAT --to-destination 1.1.1.1:echo-ftp-data/ssh;-p tcp -j DNAT --to-destination 1.1.1.1:7-20/22;OK
> >>
> >> This looks dangerous. It is why I originally never allowed service names in
> >> port ranges that use dash as the range character.
> >
> >Guess if someone is able to manipulate /etc/services, any service names
> >are problematic, not just in ranges.
>
> Well, pretty much anyone has a shot at manipulating this file. File a
> port registration with IANA, and when your distro updates the file,
> eventually there is a chance of messing up firewall configs,
> worldwide.
>
> Other than that, thanks to nsswitch, the service list can also be in
> LDAP or so, and then all that's needed is a disgruntled LDAP admin
> who dislikes the firewall admin.
>
> >Another potential problem I didn't have in mind though is that 'a-b'
> >could mean [a; b] or [a-b] assuming that all three exist. But I haven't
> >found a valid example in my /etc/services, yet. :)
>
> I found 25 at once!
>
> 914c :: 914c-g :: g-talk
> ads :: ads-s :: s-openmail
> bctp :: bctp-server :: server-find
> cis :: cis-secure :: secure-mqtt
> connect :: connect-server :: server-find
> docker :: docker-s :: s-openmail
> documentum :: documentum-s :: s-openmail
> domain :: domain-s :: s-openmail
> dtp :: dtp-net :: net-device
> genie :: genie-lm :: lm-mon
> linktest :: linktest-s :: s-openmail
> mailbox :: mailbox-lm :: lm-mon
> mbap :: mbap-s :: s-openmail
> ns :: ns-server :: server-find
> plato :: plato-lm :: lm-mon
> rmonitor :: rmonitor-secure :: secure-mqtt
> sentinel :: sentinel-lm :: lm-mon
> sitewatch :: sitewatch-s :: s-openmail
> spss :: spss-lm :: lm-mon
> sql :: sql-net :: net-device
> tacacs :: tacacs-ds :: ds-slp
> tl1 :: tl1-lv :: lv-auth
> trim :: trim-ice :: ice-router
> wnn6 :: wnn6-ds :: ds-slp
> wsdapi :: wsdapi-s :: s-openmail
Your /etc/services seems to be much larger than mine, many of those
don't exist in my case.
> To be read as: "wsdapi-s-openmail" is ambiguous, because
> it allows for two interpretations (and all four port names are in
> /etc/services):
>
> [wsdapi]-[s-openmail]
> [wsdapi-s]-[openmail]
OK. My code preferred the latter, checking if the former is possible is
a poor workaround. The only difference it makes is rules get rejected
instead of changing behaviour silently.
> >> The "solution" would be to use : as the range character, but that would require
> >> a new --dport option for reasons of command-line compatibility.
> >
> >Well, we could allow both (a-b with numeric a and b only) and use it in
> >output only if non-numeric was requested.
>
> Given I'm seeing "914c" in the IANA list (leading digits always stand
> out from the crowd, e.g. you don't normally see them in UNIX
> usernames either), I won't hold my breath that no one would try to
> register "914-915".
That's an interesting point: "914c" is not usable in iptables. The code
tries strtoul which succeeds for "914", "c" is then rejected as illegal
remainder. To fix that, we had to consult getservbyname() first which is
a performance hit. Guess the whole "support users with bad number
memory" game is best effort, only.
I'll submit a v2 without the experimental "names in ranges" patch in a
minute.
Thanks, Phil
^ permalink raw reply [flat|nested] 14+ messages in thread