[Fix] Fix O(N^2) algorithm

diff --git a/src/libmime/mime_expressions.c b/src/libmime/mime_expressions.c
index e797bb9b6e53ca349086077787048093806a70cf..ea46233ecd04ae63a3f1f6ad4d7e1f839b82c66e 100644 (file)
--- a/src/libmime/mime_expressions.c
+++ b/src/libmime/mime_expressions.c
@@ -1309,6 +1309,19 @@ struct addr_list {
        guint addrlen;
 };
 
+static gint
+addr_list_cmp_func (const void *a, const void *b)
+{
+       const struct addr_list *addra = (struct addr_list *)a,
+                       *addrb = (struct addr_list *)b;
+
+       if (addra->addrlen != addrb->addrlen) {
+               return addra->addrlen - addrb->addrlen;
+       }
+
+       return memcmp (addra->addr, addrb->addr, addra->addrlen);
+}
+
 #define COMPARE_RCPT_LEN 3
 #define MIN_RCPT_TO_COMPARE 7
 
@@ -1320,7 +1333,7 @@ rspamd_recipients_distance (struct rspamd_task *task, GArray * args,
        struct rspamd_email_address *cur;
        double threshold;
        struct addr_list *ar;
-       gint num, i, j, hits = 0, total = 0;
+       gint num, i, hits = 0;
 
        if (args == NULL) {
                msg_warn_task ("no parameters to function");
@@ -1356,27 +1369,31 @@ rspamd_recipients_distance (struct rspamd_task *task, GArray * args,
        ar = rspamd_mempool_alloc0 (task->task_pool, num * sizeof (struct addr_list));
 
        /* Fill array */
+       num = 0;
        PTR_ARRAY_FOREACH (MESSAGE_FIELD (task, rcpt_mime), i, cur) {
-               ar[i].name = cur->addr;
-               ar[i].namelen = cur->addr_len;
-               ar[i].addr = cur->domain;
-               ar[i].addrlen = cur->domain_len;
+               if (cur->addr_len > COMPARE_RCPT_LEN) {
+                       ar[num].name = cur->addr;
+                       ar[num].namelen = cur->addr_len;
+                       ar[num].addr = cur->domain;
+                       ar[num].addrlen = cur->domain_len;
+                       num ++;
+               }
        }
 
+       qsort (ar, num, sizeof (*ar), addr_list_cmp_func);
+
        /* Cycle all elements in array */
        for (i = 0; i < num; i++) {
-               for (j = i + 1; j < num; j++) {
-                       if (ar[i].namelen >= COMPARE_RCPT_LEN && ar[j].namelen >= COMPARE_RCPT_LEN &&
-                               rspamd_lc_cmp (ar[i].name, ar[j].name, COMPARE_RCPT_LEN) == 0) {
-                               /* Common name part */
-                               hits++;
+               if (i < num - 1) {
+                       if (ar[i].namelen == ar[i + 1].namelen) {
+                               if (rspamd_lc_cmp (ar[i].name, ar[i + 1].name, COMPARE_RCPT_LEN) == 0) {
+                                       hits++;
+                               }
                        }
-
-                       total++;
                }
        }
 
-       if ((hits * num / 2.) / (double)total >= threshold) {
+       if ((hits * num / 2.) / (double)num >= threshold) {
                return TRUE;
        }