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authorPhil Sutter <phil@nwl.cc>2022-04-12 21:19:39 +0200
committerPhil Sutter <phil@nwl.cc>2022-11-11 19:13:10 +0100
commitf30c5edce0413b2b2346c7f58e801f10f6e9bc5a (patch)
tree3af9c625b5f54d2016e8fe4f8a2dccaea0fd4cda /extensions/libipt_SNAT.c
parent0c0807bed45568b458980e65691ec4482aeb1cf3 (diff)
extensions: Merge SNAT, DNAT, REDIRECT and MASQUERADE
REDIRECT was already merged into DNAT. Given the callback generator and generalized inner parsing routines, merging the other "flavors" is relatively simple. Rename the extension into "libxt_NAT.so" while doing so and turn the old DSOs into symlinks. Signed-off-by: Phil Sutter <phil@nwl.cc>
Diffstat (limited to 'extensions/libipt_SNAT.c')
-rw-r--r--extensions/libipt_SNAT.c276
1 files changed, 0 insertions, 276 deletions
diff --git a/extensions/libipt_SNAT.c b/extensions/libipt_SNAT.c
deleted file mode 100644
index 9c8cdb46..00000000
--- a/extensions/libipt_SNAT.c
+++ /dev/null
@@ -1,276 +0,0 @@
-#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_ipv4/ip_tables.h>
-#include <linux/netfilter/nf_nat.h>
-
-enum {
- O_TO_SRC = 0,
- O_RANDOM,
- O_RANDOM_FULLY,
- O_PERSISTENT,
-};
-
-static void SNAT_help(void)
-{
- printf(
-"SNAT target options:\n"
-" --to-source [<ipaddr>[-<ipaddr>]][:port[-port]]\n"
-" Address to map source to.\n"
-"[--random] [--random-fully] [--persistent]\n");
-}
-
-static const struct xt_option_entry SNAT_opts[] = {
- {.name = "to-source", .id = O_TO_SRC, .type = XTTYPE_STRING,
- .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},
- XTOPT_TABLEEND,
-};
-
-/* Ranges expected in network order. */
-static void
-parse_to(const char *orig_arg, int portok, struct nf_nat_ipv4_range *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.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);
- 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_ip = ip->s_addr;
- 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;
-
- free(arg);
- return;
-}
-
-static void SNAT_parse(struct xt_option_call *cb)
-{
- struct nf_nat_ipv4_multi_range_compat *mr = cb->data;
- const struct ipt_entry *entry = cb->xt_entry;
- 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_SRC:
- parse_to(cb->arg, portok, mr->range);
- break;
- case O_PERSISTENT:
- mr->range->flags |= NF_NAT_RANGE_PERSISTENT;
- break;
- case O_RANDOM:
- mr->range->flags |= NF_NAT_RANGE_PROTO_RANDOM;
- break;
- case O_RANDOM_FULLY:
- mr->range->flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
- break;
- }
-}
-
-static void SNAT_fcheck(struct xt_fcheck_call *cb)
-{
- struct nf_nat_ipv4_multi_range_compat *mr = cb->data;
-
- mr->rangesize = 1;
-}
-
-static void print_range(const struct nf_nat_ipv4_range *r)
-{
- if (r->flags & NF_NAT_RANGE_MAP_IPS) {
- struct in_addr a;
-
- 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_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));
- }
-}
-
-static void SNAT_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_PROTO_RANDOM_FULLY)
- printf(" random-fully");
- if (mr->range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" persistent");
-}
-
-static void SNAT_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-source ");
- print_range(mr->range);
- if (mr->range->flags & NF_NAT_RANGE_PROTO_RANDOM)
- printf(" --random");
- if (mr->range->flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY)
- printf(" --random-fully");
- if (mr->range->flags & NF_NAT_RANGE_PERSISTENT)
- printf(" --persistent");
-}
-
-static void print_range_xlate(const struct nf_nat_ipv4_range *r,
- struct xt_xlate *xl)
-{
- if (r->flags & NF_NAT_RANGE_MAP_IPS) {
- struct in_addr a;
-
- 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));
- }
- }
- if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
- xt_xlate_add(xl, ":");
- 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));
- }
-}
-
-static int SNAT_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, "snat 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_PROTO_RANDOM_FULLY) {
- if (sep_need)
- sep = ",";
- xt_xlate_add(xl, "%sfully-random", sep);
- sep_need = true;
- }
- if (mr->range->flags & NF_NAT_RANGE_PERSISTENT) {
- if (sep_need)
- sep = ",";
- xt_xlate_add(xl, "%spersistent", sep);
- }
-
- return 1;
-}
-
-static struct xtables_target snat_tg_reg = {
- .name = "SNAT",
- .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 = SNAT_help,
- .x6_parse = SNAT_parse,
- .x6_fcheck = SNAT_fcheck,
- .print = SNAT_print,
- .save = SNAT_save,
- .x6_options = SNAT_opts,
- .xlate = SNAT_xlate,
-};
-
-void _init(void)
-{
- xtables_register_target(&snat_tg_reg);
-}