rbl filter implementation.
authorFlorent Bruneau <florent.bruneau@polytechnique.org>
Sat, 13 Sep 2008 15:46:00 +0000 (17:46 +0200)
committerFlorent Bruneau <florent.bruneau@polytechnique.org>
Sat, 13 Sep 2008 15:46:00 +0000 (17:46 +0200)
Signed-off-by: Florent Bruneau <florent.bruneau@polytechnique.org>
common/array.h
postlicyd/config.c
postlicyd/filter.c
postlicyd/rbl.c
postlicyd/rbl.h

index ed12b5b..6cb7619 100644 (file)
@@ -48,6 +48,7 @@
     }
 #define ARRAY(Type)                                                            \
     typedef PRIV_ARRAY(Type) Type ## _array_t;                                 \
+    typedef PRIV_ARRAY(Type*) Type ## _ptr_array_t;                            \
                                                                                \
     static inline Type ## _array_t *Type ## _array_new(void)                   \
     {                                                                          \
     }                                                                          \
                                                                                \
     static inline void Type ## _array_delete(Type ## _array_t **array)         \
+    {                                                                          \
+        if (*array) {                                                          \
+            array_wipe(**array);                                               \
+            p_delete(array);                                                   \
+        }                                                                      \
+    }                                                                          \
+                                                                               \
+    static inline Type ## _ptr_array_t *Type ## _ptr_array_new(void)           \
+    {                                                                          \
+        return p_new(Type ## _ptr_array_t, 1);                                 \
+    }                                                                          \
+                                                                               \
+    static inline void Type ## _ptr_array_delete(Type ## _ptr_array_t **array) \
     {                                                                          \
         if (*array) {                                                          \
             array_wipe(**array);                                               \
@@ -62,6 +76,7 @@
         }                                                                      \
     }
 #define A(Type) Type ## _array_t
+#define PA(Type) Type ## _ptr_array_t
 
 #define ARRAY_INIT { NULL, 0, 0 }
 
index 871a71f..21e49d1 100644 (file)
@@ -36,6 +36,7 @@
 #include "file.h"
 #include "filter.h"
 #include "config.h"
+#include "str.h"
 
 struct config_t {
     A(filter_t)        filters;
@@ -234,8 +235,8 @@ read_param_value:
     READ_STRING("parameter value", value, value_len, ;);
     {
         filter_params_t param;
-        param.name = strdup(key);
-        param.value = strdup(value);
+        param.name = m_strdup(key);
+        param.value = m_strdup(value);
         array_add(config->params, param);
     }
     goto read_section;
index da78992..deb3190 100644 (file)
@@ -46,6 +46,9 @@ void filter_register(const char *type, filter_constructor_t constructor,
 {
     filter_token tok = filter_tokenize(type, m_strlen(type));
     assert(tok != FTK_UNKNOWN && "Unknown filter type");
+
+    syslog(LOG_INFO, "filter type %s registered", type);
+
     runners[tok] = runner;
     constructors[tok] = constructor;
     destructors[tok] = destructor;
@@ -121,8 +124,8 @@ bool filter_add_param(filter_t *filter, const char *name, ssize_t name_len,
                       const char *value, ssize_t value_len)
 {
     filter_params_t param;
-    param.name = strdup(name);
-    param.value = strdup(value);
+    param.name = m_strdup(name);
+    param.value = m_strdup(value);
     array_add(filter->params, param);
     return true;
 }
@@ -131,9 +134,9 @@ bool filter_add_hook(filter_t *filter, const char *name, ssize_t name_len,
                      const char *value, ssize_t value_len)
 {
     filter_hook_t hook;
-    hook.name  = strdup(name);
+    hook.name  = m_strdup(name);
     hook.postfix = (strncmp(value, "postfix:", 8) == 0);
-    hook.value = strdup(hook.postfix ? value + 8 : value);
+    hook.value = m_strdup(hook.postfix ? value + 8 : value);
     hook.filter_id = -1;
     array_add(filter->hooks, hook);
     return true;
index 7bf6357..3ded455 100644 (file)
@@ -52,6 +52,8 @@
 #define DEBUG(...)
 #endif
 
+/* Implementation */
+
 enum {
     BALANCED    = 0,
     LEFT_HEAVY  = 1,
@@ -62,6 +64,7 @@ struct rbldb_t {
     A(uint32_t) ips;
     bool        locked;
 };
+ARRAY(rbldb_t)
 
 static int get_o(const char *s, const char **out)
 {
@@ -170,23 +173,28 @@ rbldb_t *rbldb_create(const char *file, bool lock)
     return db;
 }
 
+static void rbldb_wipe(rbldb_t *db)
+{
+    if (db->locked) {
+      array_unlock(db->ips);
+    }
+    array_wipe(db->ips);
+}
+
 void rbldb_delete(rbldb_t **db)
 {
     if (*db) {
-        if ((*db)->locked) {
-            array_unlock((*db)->ips);
-        }
-        array_wipe((*db)->ips);
+        rbldb_wipe(*db);
         p_delete(&(*db));
     }
 }
 
-uint32_t rbldb_stats(rbldb_t *rbl)
+uint32_t rbldb_stats(const rbldb_t *rbl)
 {
     return rbl->ips.len;
 }
 
-bool rbldb_ipv4_lookup(rbldb_t *db, uint32_t ip)
+bool rbldb_ipv4_lookup(const rbldb_t *db, uint32_t ip)
 {
     int l = 0, r = db->ips.len;
 
@@ -204,3 +212,171 @@ bool rbldb_ipv4_lookup(rbldb_t *db, uint32_t ip)
     }
     return false;
 }
+
+
+/* postlicyd filter declaration */
+
+#include "filter.h"
+
+typedef struct rbl_filter_t {
+    PA(rbldb_t) rbls;
+    A(int)      weights;
+
+    int32_t     hard_threshold;
+    int32_t     soft_threshold;
+} rbl_filter_t;
+
+static rbl_filter_t *rbl_filter_new(void)
+{
+    return p_new(rbl_filter_t, 1);
+}
+
+static void rbl_filter_delete(rbl_filter_t **rbl)
+{
+    if (*rbl) {
+        array_deep_wipe((*rbl)->rbls, rbldb_delete);
+        array_wipe((*rbl)->weights);
+        p_delete(rbl);
+    }
+}
+
+
+static bool rbl_filter_constructor(filter_t *filter)
+{
+    rbl_filter_t *data = rbl_filter_new();
+
+#define PARSE_CHECK(Expr, Str, ...)                                            \
+    if (!(Expr)) {                                                             \
+        syslog(LOG_ERR, Str, ##__VA_ARGS__);                                   \
+        rbl_filter_delete(&data);                                              \
+        return false;                                                          \
+    }
+
+    foreach (filter_params_t *param, filter->params) {
+        /* file parameter is:
+         *  [no]lock:weight:filename
+         *  valid options are:
+         *    - lock:   memlock the database in memory.
+         *    - nolock: don't memlock the database in memory [default].
+         *    - \d+:    a number describing the weight to give to the match
+         *              the given list [mandatory]
+         *  the file pointed by filename MUST be a valid ip list issued from
+         *  the rsync (or equivalent) service of a (r)bl.
+         */
+        if (strcmp(param->name, "file") == 0) {
+            bool lock = false;
+            int  weight = 0;
+            rbldb_t *rbl = NULL;
+            const char *current = param->value;
+            const char *p = m_strchrnul(param->value, ':');
+            char *next = NULL;
+            for (int i = 0 ; i < 3 ; ++i) {
+                PARSE_CHECK(i == 2 || *p, 
+                            "file parameter must contains a locking state and a weight option");
+                switch (i) {
+                  case 0:
+                    if ((p - current) == 4 && strncmp(current, "lock", 4) == 0) {
+                        lock = true;
+                    } else if ((p - current) == 6 && strncmp(current, "nolock", 6) == 0) {
+                        lock = false;
+                    } else {
+                        PARSE_CHECK(false, "illegal locking state %.*s",
+                                    p - current, current);
+                    }
+                    break;
+
+                  case 1:
+                    weight = strtol(current, &next, 10);
+                    PARSE_CHECK(next == p && weight >= 0 && weight <= 1024,
+                                "illegal weight value %.*s",
+                                (p - current), current);
+                    break;
+
+                  case 2:
+                    rbl = rbldb_create(current, lock);
+                    PARSE_CHECK(rbl != NULL,
+                                "cannot load rbl db from %s", current);
+                    array_add(data->rbls, rbl);
+                    array_add(data->weights, weight);
+                    break;
+                }
+                current = p + 1;
+                p = m_strchrnul(current, ':');
+            }
+
+        /* hard_threshold parameter is an integer.
+         *  If the matching score of a ip get a score gretter than this threshold,
+         *  the hook "hard_match" is called.
+         * hard_threshold = 0 means, that all matches are hard matches.
+         * default is 0;
+         */
+        } else if (strcmp(param->name, "hard_threshold") == 0) {
+            char *next;
+            data->hard_threshold = strtol(param->value, &next, 10);
+            PARSE_CHECK(*next, "invalid threshold value %s", param->value);
+
+        /* soft_threshold parameter is an integer.
+         *  if the matching score of an ip get a score getter than this threshold
+         *  and smaller or equal than the hard_threshold, the hook "soft_match"
+         *  is called.
+         * default is 0;
+         */
+        } else if (strcmp(param->name, "hard_threshold") == 0) {
+            char *next;
+            data->soft_threshold = strtol(param->value, &next, 10);
+            PARSE_CHECK(*next, "invalid threshold value %s", param->value);
+
+        } else {
+            syslog(LOG_INFO, "ignored parameter %s in rbl filter %s",
+                   filter->name, param->name);
+        }
+    }}
+
+    PARSE_CHECK(data->rbls.len, 
+                "no file parameter in the filter %s", filter->name);
+    filter->data = data;
+    return true;
+}
+
+static void rbl_filter_destructor(filter_t *filter)
+{
+    rbl_filter_t *data = filter->data;
+    rbl_filter_delete(&data);
+    filter->data = data;
+}
+
+static filter_result_t rbl_filter(const filter_t *filter, const query_t *query)
+{
+    uint32_t ip;
+    int32_t sum = 0;
+    const char *end = NULL;
+    const rbl_filter_t *data = filter->data;
+
+    if (parse_ipv4(query->client_address, &end, &ip) != 0) {
+        syslog(LOG_WARNING, "invalid client address: %s, expected ipv4",
+               query->client_address);
+        return "error";
+    }
+    for (int i = 0 ; i < data->rbls.len ; ++i) {
+        const rbldb_t *rbl = array_elt(data->rbls, i);
+        int weight   = array_elt(data->weights, i);
+        if (rbldb_ipv4_lookup(rbl, ip)) {
+            sum += weight;
+        }
+    }
+    if (sum > data->hard_threshold) {
+        return "hard_match";
+    } else if (sum > data->soft_threshold) {
+        return "soft_match";
+    } else {
+        return "fail";
+    }
+}
+
+static int rbl_init(void)
+{
+    filter_register("rbl", rbl_filter_constructor, rbl_filter_destructor,
+                    rbl_filter);
+    return 0;
+}
+module_init(rbl_init);
index 2c6b879..dc9a03d 100644 (file)
@@ -42,7 +42,7 @@ typedef struct rbldb_t rbldb_t;
 rbldb_t *rbldb_create(const char *file, bool lock);
 void rbldb_delete(rbldb_t **);
 
-uint32_t rbldb_stats(rbldb_t *rbl);
-bool rbldb_ipv4_lookup(rbldb_t *rbl, uint32_t ip);
+uint32_t rbldb_stats(const rbldb_t *rbl);
+bool rbldb_ipv4_lookup(const rbldb_t *rbl, uint32_t ip);
 
 #endif