Patrick McHardy wrote:
> I took on Ben's challenge to increase the number of possible routing tables,
> these are the resulting patches.
>
> The table IDs are changed to 32 bit values and are contained in a new netlink
> routing attribute. For compatibility rtm_table in struct rtmsg can still be
> used to access the first 255 tables and contains the low 8 bit of the table
> ID in case of dumps. Unfortunately there are no invalid values for rtm_table,
> so the best userspace can do in case of a new iproute version that tries to
> access tables > 255 on an old kernel is to use RTM_UNSPEC (0) for rtm_table,
> which will make the kernel allocate an empty table instead of silently adding
> routes to a more or less random table. The iproute patch will follow shortly.
Actually that last part wasn't entirely true. The last couple of
releases of the kernel include the inet_check_attr function,
which (unwillingly) breaks with the tradition of ignoring
unknown attributes and signals an error on receiving the RTA_TABLE
attribute. So the iproute patch only includes the RTA_TABLE
attribute when the table ID is > 255, in which case rtm_table
is set to RT_TABLE_UNSPEC. Old kernels will still have the
behaviour I described above. The patch has been tested to
behave as expected on both patched and unpatched kernels.
diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index 5e33a20..7573c62 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -238,9 +238,8 @@ enum rt_class_t
RT_TABLE_DEFAULT=253,
RT_TABLE_MAIN=254,
RT_TABLE_LOCAL=255,
- __RT_TABLE_MAX
};
-#define RT_TABLE_MAX (__RT_TABLE_MAX - 1)
+#define RT_TABLE_MAX 0xFFFFFFFF
@@ -263,6 +262,7 @@ enum rtattr_type_t
RTA_CACHEINFO,
RTA_SESSION,
RTA_MP_ALGO,
+ RTA_TABLE,
__RTA_MAX
};
diff --git a/include/rt_names.h b/include/rt_names.h
index 2d9ef10..07a10e0 100644
--- a/include/rt_names.h
+++ b/include/rt_names.h
@@ -5,7 +5,7 @@ #include <asm/types.h>
char* rtnl_rtprot_n2a(int id, char *buf, int len);
char* rtnl_rtscope_n2a(int id, char *buf, int len);
-char* rtnl_rttable_n2a(int id, char *buf, int len);
+char* rtnl_rttable_n2a(__u32 id, char *buf, int len);
char* rtnl_rtrealm_n2a(int id, char *buf, int len);
char* rtnl_dsfield_n2a(int id, char *buf, int len);
int rtnl_rtprot_a2n(__u32 *id, char *arg);
diff --git a/ip/ip_common.h b/ip/ip_common.h
index 1fe4a69..8b286b0 100644
--- a/ip/ip_common.h
+++ b/ip/ip_common.h
@@ -32,4 +32,12 @@ extern int do_multiaddr(int argc, char *
extern int do_multiroute(int argc, char **argv);
extern int do_xfrm(int argc, char **argv);
+static inline int rtm_get_table(struct rtmsg *r, struct rtattr **tb)
+{
+ __u32 table = r->rtm_table;
+ if (tb[RTA_TABLE])
+ table = *(__u32*) RTA_DATA(tb[RTA_TABLE]);
+ return table;
+}
+
extern struct rtnl_handle rth;
diff --git a/ip/iproute.c b/ip/iproute.c
index a43c09e..4ebe617 100644
--- a/ip/iproute.c
+++ b/ip/iproute.c
@@ -75,7 +75,8 @@ static void usage(void)
static struct
{
- int tb;
+ __u32 tb;
+ int cloned;
int flushed;
char *flushb;
int flushp;
@@ -125,6 +126,7 @@ int print_route(const struct sockaddr_nl
inet_prefix prefsrc;
inet_prefix via;
int host_len = -1;
+ __u32 table;
SPRINT_BUF(b1);
@@ -151,27 +153,23 @@ int print_route(const struct sockaddr_nl
host_len = 80;
if (r->rtm_family == AF_INET6) {
+ if (filter.cloned) {
+ if (!(r->rtm_flags&RTM_F_CLONED))
+ return 0;
+ }
if (filter.tb) {
- if (filter.tb < 0) {
- if (!(r->rtm_flags&RTM_F_CLONED))
- return 0;
- } else {
- if (r->rtm_flags&RTM_F_CLONED)
+ if (r->rtm_flags&RTM_F_CLONED)
+ return 0;
+ if (filter.tb == RT_TABLE_LOCAL) {
+ if (r->rtm_type != RTN_LOCAL)
return 0;
- if (filter.tb == RT_TABLE_LOCAL) {
- if (r->rtm_type != RTN_LOCAL)
- return 0;
- } else if (filter.tb == RT_TABLE_MAIN) {
- if (r->rtm_type == RTN_LOCAL)
- return 0;
- } else {
+ } else if (filter.tb == RT_TABLE_MAIN) {
+ if (r->rtm_type == RTN_LOCAL)
return 0;
- }
+ } else {
+ return 0;
}
}
- } else {
- if (filter.tb > 0 && filter.tb != r->rtm_table)
- return 0;
}
if ((filter.protocol^r->rtm_protocol)&filter.protocolmask)
return 0;
@@ -225,6 +223,10 @@ int print_route(const struct sockaddr_nl
memcpy(&prefsrc.data, RTA_DATA(tb[RTA_PREFSRC]),
host_len/8);
}
+ table = rtm_get_table(r, tb);
+ if (r->rtm_family == AF_INET && filter.tb > 0 && filter.tb != table)
+ return 0;
+
if (filter.rdst.family && inet_addr_match(&dst, &filter.rdst,
filter.rdst.bitlen))
return 0;
if (filter.mdst.family && filter.mdst.bitlen >= 0 &&
@@ -354,8 +356,8 @@ int print_route(const struct sockaddr_nl
fprintf(fp, "dev %s ",
ll_index_to_name(*(int*)RTA_DATA(tb[RTA_OIF])));
if (!(r->rtm_flags&RTM_F_CLONED)) {
- if (r->rtm_table != RT_TABLE_MAIN && !filter.tb)
- fprintf(fp, " table %s ",
rtnl_rttable_n2a(r->rtm_table, b1, sizeof(b1)));
+ if (table != RT_TABLE_MAIN && !filter.tb)
+ fprintf(fp, " table %s ", rtnl_rttable_n2a(table, b1,
sizeof(b1)));
if (r->rtm_protocol != RTPROT_BOOT && filter.protocolmask != -1)
fprintf(fp, " proto %s ",
rtnl_rtprot_n2a(r->rtm_protocol, b1, sizeof(b1)));
if (r->rtm_scope != RT_SCOPE_UNIVERSE && filter.scopemask != -1)
@@ -840,7 +842,12 @@ #endif
NEXT_ARG();
if (rtnl_rttable_a2n(&tid, *argv))
invarg("\"table\" value is invalid\n", *argv);
- req.r.rtm_table = tid;
+ if (tid < 256)
+ req.r.rtm_table = tid;
+ else {
+ req.r.rtm_table = RT_TABLE_UNSPEC;
+ addattr32(&req.n, sizeof(req), RTA_TABLE, tid);
+ }
table_ok = 1;
} else if (strcmp(*argv, "dev") == 0 ||
strcmp(*argv, "oif") == 0) {
@@ -1022,7 +1029,7 @@ static int iproute_list_or_flush(int arg
filter.tb = tid;
} else if (matches(*argv, "cached") == 0 ||
matches(*argv, "cloned") == 0) {
- filter.tb = -1;
+ filter.cloned = 1;
} else if (strcmp(*argv, "tos") == 0 ||
matches(*argv, "dsfield") == 0) {
__u32 tos;
diff --git a/ip/iprule.c b/ip/iprule.c
index ccf699f..6caf573 100644
--- a/ip/iprule.c
+++ b/ip/iprule.c
@@ -27,6 +27,7 @@ #include <string.h>
#include "rt_names.h"
#include "utils.h"
+#include "ip_common.h"
extern struct rtnl_handle rth;
@@ -51,6 +52,7 @@ static int print_rule(const struct socka
struct rtmsg *r = NLMSG_DATA(n);
int len = n->nlmsg_len;
int host_len = -1;
+ __u32 table;
struct rtattr * tb[RTA_MAX+1];
char abuf[256];
SPRINT_BUF(b1);
@@ -129,8 +131,9 @@ static int print_rule(const struct socka
fprintf(fp, "iif %s ", (char*)RTA_DATA(tb[RTA_IIF]));
}
- if (r->rtm_table)
- fprintf(fp, "lookup %s ", rtnl_rttable_n2a(r->rtm_table, b1,
sizeof(b1)));
+ table = rtm_get_table(r, tb);
+ if (table)
+ fprintf(fp, "lookup %s ", rtnl_rttable_n2a(table, b1,
sizeof(b1)));
if (tb[RTA_FLOW]) {
__u32 to = *(__u32*)RTA_DATA(tb[RTA_FLOW]);
@@ -257,7 +260,12 @@ static int iprule_modify(int cmd, int ar
NEXT_ARG();
if (rtnl_rttable_a2n(&tid, *argv))
invarg("invalid table ID\n", *argv);
- req.r.rtm_table = tid;
+ if (tid < 256)
+ req.r.rtm_table = tid;
+ else {
+ req.r.rtm_table = RT_TABLE_UNSPEC;
+ addattr32(&req.n, sizeof(req), RTA_TABLE, tid);
+ }
table_ok = 1;
} else if (strcmp(*argv, "dev") == 0 ||
strcmp(*argv, "iif") == 0) {
diff --git a/lib/rt_names.c b/lib/rt_names.c
index 05046c2..2ff984a 100644
--- a/lib/rt_names.c
+++ b/lib/rt_names.c
@@ -23,6 +23,51 @@ #include <linux/rtnetlink.h>
#include "rt_names.h"
+struct rtnl_hash_entry {
+ struct rtnl_hash_entry *next;
+ unsigned int id;
+ char * name;
+};
+
+static void
+rtnl_hash_initialize(char *file, struct rtnl_hash_entry **hash, int size)
+{
+ struct rtnl_hash_entry *entry;
+ char buf[512];
+ FILE *fp;
+
+ fp = fopen(file, "r");
+ if (!fp)
+ return;
+ while (fgets(buf, sizeof(buf), fp)) {
+ char *p = buf;
+ int id;
+ char namebuf[512];
+
+ while (*p == ' ' || *p == '\t')
+ p++;
+ if (*p == '#' || *p == '\n' || *p == 0)
+ continue;
+ if (sscanf(p, "0x%x %s\n", &id, namebuf) != 2 &&
+ sscanf(p, "0x%x %s #", &id, namebuf) != 2 &&
+ sscanf(p, "%d %s\n", &id, namebuf) != 2 &&
+ sscanf(p, "%d %s #", &id, namebuf) != 2) {
+ fprintf(stderr, "Database %s is corrupted at %s\n",
+ file, p);
+ return;
+ }
+
+ if (id<0)
+ continue;
+ entry = malloc(sizeof(*entry));
+ entry->id = id;
+ entry->name = strdup(namebuf);
+ entry->next = hash[id & (size - 1)];
+ hash[id & (size - 1)] = entry;
+ }
+ fclose(fp);
+}
+
static void rtnl_tab_initialize(char *file, char **tab, int size)
{
char buf[512];
@@ -57,7 +102,6 @@ static void rtnl_tab_initialize(char *fi
fclose(fp);
}
-
static char * rtnl_rtprot_tab[256] = {
[RTPROT_UNSPEC] = "none",
[RTPROT_REDIRECT] ="redirect",
@@ -266,9 +310,14 @@ int rtnl_rtrealm_a2n(__u32 *id, char *ar
}
+static struct rtnl_hash_entry dflt_table_entry = { .id = 253, .name =
"default" };
+static struct rtnl_hash_entry main_table_entry = { .id = 254, .name = "main"
};
+static struct rtnl_hash_entry local_table_entry = { .id = 255, .name = "local"
};
-static char * rtnl_rttable_tab[256] = {
- "unspec",
+static struct rtnl_hash_entry * rtnl_rttable_hash[256] = {
+ [253] = &dflt_table_entry,
+ [254] = &main_table_entry,
+ [255] = &local_table_entry,
};
static int rtnl_rttable_init;
@@ -276,26 +325,26 @@ static int rtnl_rttable_init;
static void rtnl_rttable_initialize(void)
{
rtnl_rttable_init = 1;
- rtnl_rttable_tab[255] = "local";
- rtnl_rttable_tab[254] = "main";
- rtnl_rttable_tab[253] = "default";
- rtnl_tab_initialize("/etc/iproute2/rt_tables",
- rtnl_rttable_tab, 256);
+ rtnl_hash_initialize("/etc/iproute2/rt_tables",
+ rtnl_rttable_hash, 256);
}
-char * rtnl_rttable_n2a(int id, char *buf, int len)
+char * rtnl_rttable_n2a(__u32 id, char *buf, int len)
{
- if (id<0 || id>=256) {
- snprintf(buf, len, "%d", id);
+ struct rtnl_hash_entry *entry;
+
+ if (id >= RT_TABLE_MAX) {
+ snprintf(buf, len, "%u", id);
return buf;
}
- if (!rtnl_rttable_tab[id]) {
- if (!rtnl_rttable_init)
- rtnl_rttable_initialize();
- }
- if (rtnl_rttable_tab[id])
- return rtnl_rttable_tab[id];
- snprintf(buf, len, "%d", id);
+ if (!rtnl_rttable_init)
+ rtnl_rttable_initialize();
+ entry = rtnl_rttable_hash[id & 255];
+ while (entry && entry->id != id)
+ entry = entry->next;
+ if (entry)
+ return entry->name;
+ snprintf(buf, len, "%u", id);
return buf;
}
@@ -303,8 +352,9 @@ int rtnl_rttable_a2n(__u32 *id, char *ar
{
static char *cache = NULL;
static unsigned long res;
+ struct rtnl_hash_entry *entry;
char *end;
- int i;
+ __u32 i;
if (cache && strcmp(cache, arg) == 0) {
*id = res;
@@ -315,9 +365,11 @@ int rtnl_rttable_a2n(__u32 *id, char *ar
rtnl_rttable_initialize();
for (i=0; i<256; i++) {
- if (rtnl_rttable_tab[i] &&
- strcmp(rtnl_rttable_tab[i], arg) == 0) {
- cache = rtnl_rttable_tab[i];
+ entry = rtnl_rttable_hash[i];
+ while (entry && strcmp(entry->name, arg))
+ entry = entry->next;
+ if (entry) {
+ cache = entry->name;
res = i;
*id = res;
return 0;
@@ -325,7 +377,7 @@ int rtnl_rttable_a2n(__u32 *id, char *ar
}
i = strtoul(arg, &end, 0);
- if (!end || end == arg || *end || i > 255)
+ if (!end || end == arg || *end || i > RT_TABLE_MAX)
return -1;
*id = i;
return 0;
