src: assert when setting unknown attributes

If this attribute is not supported by the library, we should rise an
assertion so the client knows something is wrong, instead of silently
going through.

The only case I can think may hit this problem is version mismatch
between library and tools. This should not ever really happen, so better
bail out from the library itself in this case.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/utils.h b/include/utils.h
index 46ff18a1fa769bdf3db685cf5c2553f3026d3b42..21694b6ab19126be369b3e599fff8194dcb1d13b 100644 (file)
--- a/include/utils.h
+++ b/include/utils.h
@@ -43,6 +43,15 @@ void __nftnl_assert_fail(uint16_t attr, const char *filename, int line);
                nftnl_assert(data, attr, _validate_array[_attr] == _data_len);  \
 })
 
+void __nftnl_assert_attr_exists(uint16_t attr, uint16_t attr_max,
+                               const char *filename, int line);
+
+#define nftnl_assert_attr_exists(_attr, _attr_max)                                     \
+({                                                                                     \
+       if (_attr > _attr_max)                                                          \
+               __nftnl_assert_attr_exists(_attr, _attr_max, __FILE__, __LINE__);       \
+})
+
 #define SNPRINTF_BUFFER_SIZE(ret, size, len, offset)   \
        if (ret < 0)                                    \
                return ret;                             \

diff --git a/src/chain.c b/src/chain.c
index 990c576613a6649ed42f8a8ae437f27446fbe28b..c7a9597eef995a17f7e8bf8a08523d431330830a 100644 (file)
--- a/src/chain.c
+++ b/src/chain.c
@@ -168,9 +168,7 @@ static uint32_t nftnl_chain_validate[NFTNL_CHAIN_MAX + 1] = {
 void nftnl_chain_set_data(struct nftnl_chain *c, uint16_t attr,
                             const void *data, uint32_t data_len)
 {
-       if (attr > NFTNL_CHAIN_MAX)
-               return;
-
+       nftnl_assert_attr_exists(attr, NFTNL_CHAIN_MAX);
        nftnl_assert_validate(data, nftnl_chain_validate, attr, data_len);
 
        switch(attr) {

diff --git a/src/gen.c b/src/gen.c
index 115a1058ba61e320e4d3a42d9d9e6b9bc4e1c5f8..ea29e2a290f4a069cea6150f6441250f556c89dc 100644 (file)
--- a/src/gen.c
+++ b/src/gen.c
@@ -67,9 +67,7 @@ static uint32_t nftnl_gen_validate[NFTNL_GEN_MAX + 1] = {
 void nftnl_gen_set_data(struct nftnl_gen *gen, uint16_t attr,
                           const void *data, uint32_t data_len)
 {
-       if (attr > NFTNL_GEN_MAX)
-               return;
-
+       nftnl_assert_attr_exists(attr, NFTNL_GEN_MAX);
        nftnl_assert_validate(data, nftnl_gen_validate, attr, data_len);
 
        switch (attr) {

diff --git a/src/rule.c b/src/rule.c
index 04cadaee39199fc143c48f2ff456657841fa0184..e63c9614b7c2ebcdaf021c5c0e606fed1b092ec9 100644 (file)
--- a/src/rule.c
+++ b/src/rule.c
@@ -132,9 +132,7 @@ static uint32_t nftnl_rule_validate[NFTNL_RULE_MAX + 1] = {
 void nftnl_rule_set_data(struct nftnl_rule *r, uint16_t attr,
                            const void *data, uint32_t data_len)
 {
-       if (attr > NFTNL_RULE_MAX)
-               return;
-
+       nftnl_assert_attr_exists(attr, NFTNL_RULE_MAX);
        nftnl_assert_validate(data, nftnl_rule_validate, attr, data_len);
 
        switch(attr) {

diff --git a/src/set.c b/src/set.c
index dbea93b5162bd75667e7cbdc066beef471899f9f..d2467e4c6583be261687e27b84e53ec3686ed2cd 100644 (file)
--- a/src/set.c
+++ b/src/set.c
@@ -116,9 +116,7 @@ static uint32_t nftnl_set_validate[NFTNL_SET_MAX + 1] = {
 void nftnl_set_set_data(struct nftnl_set *s, uint16_t attr, const void *data,
                           uint32_t data_len)
 {
-       if (attr > NFTNL_SET_MAX)
-               return;
-
+       nftnl_assert_attr_exists(attr, NFTNL_SET_MAX);
        nftnl_assert_validate(data, nftnl_set_validate, attr, data_len);
 
        switch(attr) {

diff --git a/src/table.c b/src/table.c
index 42fe49f8e0028834a355576970840f9426957e47..7eefc7019f05a99c81d9015e6f207f6607babc7f 100644 (file)
--- a/src/table.c
+++ b/src/table.c
@@ -87,9 +87,7 @@ static uint32_t nftnl_table_validate[NFTNL_TABLE_MAX + 1] = {
 void nftnl_table_set_data(struct nftnl_table *t, uint16_t attr,
                             const void *data, uint32_t data_len)
 {
-       if (attr > NFTNL_TABLE_MAX)
-               return;
-
+       nftnl_assert_attr_exists(attr, NFTNL_TABLE_MAX);
        nftnl_assert_validate(data, nftnl_table_validate, attr, data_len);
 
        switch (attr) {

diff --git a/src/utils.c b/src/utils.c
index 22710b94c39103122d1558114acd72a52eeaa1a6..e2715a216f18521b1a0e50455b04c39ada6c7eb7 100644 (file)
--- a/src/utils.c
+++ b/src/utils.c
@@ -269,6 +269,14 @@ out:
        return ret;
 }
 
+void __nftnl_assert_attr_exists(uint16_t attr, uint16_t attr_max,
+                               const char *filename, int line)
+{
+       fprintf(stderr, "libnftnl: attribute %d > %d (maximum) assertion failed in %s:%d\n",
+               attr, attr_max, filename, line);
+       exit(EXIT_FAILURE);
+}
+
 void __nftnl_assert_fail(uint16_t attr, const char *filename, int line)
 {
        fprintf(stderr, "libnftnl: attribute %d assertion failed in %s:%d\n",