From 191694f797639fc0b56adcf050bc9cfa8dc02f3d Mon Sep 17 00:00:00 2001
From: Luca Deri <deri@ntop.org>
Date: Thu, 19 Sep 2024 13:18:26 +0200
Subject: [PATCH] Implemented ndpi_strrstr() Fixed bug in ndpi_get_host_domain

---
 example/ndpiReader.c   |  3 +++
 src/include/ndpi_api.h | 14 +++++++-------
 src/lib/ndpi_domains.c |  4 ++--
 src/lib/ndpi_utils.c   | 26 ++++++++++++++++++++++++--
 4 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/example/ndpiReader.c b/example/ndpiReader.c
index 8a59b77e3e5..0d3a427911d 100644
--- a/example/ndpiReader.c
+++ b/example/ndpiReader.c
@@ -6258,6 +6258,9 @@ void domainsUnitTest() {
 
     assert(ndpi_load_domain_suffixes(ndpi_str, (char*)lists_path) == 0);
 
+    assert(strcmp(ndpi_get_host_domain(ndpi_str, "extension.femetrics.grammarly.io"), "grammarly.io") == 0);
+    assert(strcmp(ndpi_get_host_domain(ndpi_str, "www.ovh.commander1.com"), "commander1.com") == 0);
+
     assert(strcmp(ndpi_get_host_domain_suffix(ndpi_str, "www.chosei.chiba.jp", &suffix_id), "chosei.chiba.jp") == 0);
     assert(strcmp(ndpi_get_host_domain_suffix(ndpi_str, "www.unipi.it", &suffix_id), "it") == 0);
     assert(strcmp(ndpi_get_host_domain_suffix(ndpi_str, "mail.apple.com", &suffix_id), "com") == 0);
diff --git a/src/include/ndpi_api.h b/src/include/ndpi_api.h
index 1bc629b8392..6e0e96e2fa0 100644
--- a/src/include/ndpi_api.h
+++ b/src/include/ndpi_api.h
@@ -1907,17 +1907,17 @@ extern "C" {
     - https://varshasaini.in/k-nearest-neighbor-knn-algorithm-in-machine-learning/
 
     NOTE:
-    with ball tree, data is a vector of vector pointers (no array)    
-  */  
+    with ball tree, data is a vector of vector pointers (no array)
+  */
   ndpi_btree* ndpi_btree_init(double **data, u_int32_t n_rows, u_int32_t n_columns);
   ndpi_knn ndpi_btree_query(ndpi_btree *b, double **query_data,
 			    u_int32_t query_data_num_rows, u_int32_t query_data_num_columns,
 			    u_int32_t max_num_results);
   void ndpi_free_knn(ndpi_knn knn);
   void ndpi_free_btree(ndpi_btree *tree);
-  
+
   /* ******************************* */
-  
+
   /*
    * Finds outliers using Z-score
    * Z-Score = (Value - Mean) / StdDev
@@ -2288,8 +2288,8 @@ extern "C" {
   int64_t ndpi_strtonum(const char *numstr, int64_t minval, int64_t maxval, const char **errstrp, int base);
   int ndpi_vsnprintf(char * str, size_t size, char const * format, va_list va_args);
   int ndpi_snprintf(char * str, size_t size, char const * format, ...);
-  struct tm *ndpi_gmtime_r(const time_t *timep,
-                           struct tm *result);
+  struct tm *ndpi_gmtime_r(const time_t *timep, struct tm *result);
+  char* ndpi_strrstr(const char *haystack, const char *needle);
 
   /* ******************************* */
 
@@ -2309,7 +2309,7 @@ extern "C" {
 
   bool ndpi_serialize_flow_fingerprint(struct ndpi_detection_module_struct *ndpi_str,
 				       struct ndpi_flow_struct *flow, ndpi_serializer *serializer);
-  
+
   /* ******************************* */
 
   const char *ndpi_lru_cache_idx_to_name(lru_cache_type idx);
diff --git a/src/lib/ndpi_domains.c b/src/lib/ndpi_domains.c
index f4398b1c84a..00ef8e75605 100644
--- a/src/lib/ndpi_domains.c
+++ b/src/lib/ndpi_domains.c
@@ -122,7 +122,7 @@ const char* ndpi_get_host_domain_suffix(struct ndpi_detection_module_struct *ndp
   return(hostname);
 }
 
-/* ******************************* */
+
 
 /*
   Example
@@ -146,7 +146,7 @@ const char* ndpi_get_host_domain(struct ndpi_detection_module_struct *ndpi_str,
   if((ret == NULL) || (ret == hostname))
     return(hostname);
 
-  dot = strstr(hostname, ret);
+  dot = ndpi_strrstr(hostname, ret);
 
   if(dot == NULL || dot == hostname)
     return(hostname);
diff --git a/src/lib/ndpi_utils.c b/src/lib/ndpi_utils.c
index 6a2e237a367..a1b0a5e6e25 100644
--- a/src/lib/ndpi_utils.c
+++ b/src/lib/ndpi_utils.c
@@ -3424,8 +3424,8 @@ int tpkt_verify_hdr(const struct ndpi_packet_struct * const packet)
 
 /* ******************************************* */
 
-int64_t ndpi_strtonum(const char *numstr, int64_t minval, int64_t maxval, const char **errstrp, int base)
-{
+int64_t ndpi_strtonum(const char *numstr, int64_t minval,
+		      int64_t maxval, const char **errstrp, int base) {
   int64_t val = 0;
   char* endptr;
 
@@ -3441,14 +3441,17 @@ int64_t ndpi_strtonum(const char *numstr, int64_t minval, int64_t maxval, const
     *errstrp = "value too small";
     return 0;
   }
+
   if((val == LLONG_MAX && errno == ERANGE) || (val > maxval )) {
     *errstrp = "value too large";
     return 0;
   }
+
   if(errno != 0 && val == 0) {
     *errstrp = "generic error";
     return 0;
   }
+
   if(endptr == numstr) {
     *errstrp = "No digits were found";
     return 0;
@@ -3459,6 +3462,25 @@ int64_t ndpi_strtonum(const char *numstr, int64_t minval, int64_t maxval, const
   return val;
 }
 
+/* ****************************************************** */
+
+char* ndpi_strrstr(const char *haystack, const char *needle) {
+  char *ret = NULL;
+  
+  while(true) {
+    char *s = strstr(haystack, needle);
+    
+    if(s == NULL)
+      break;
+    else {
+      ret = s;
+      haystack = &s[1]; /* Skip the first char */
+    }
+  }
+
+  return(ret);
+}
+
 /* ******************************************* */
 
 const char *ndpi_lru_cache_idx_to_name(lru_cache_type idx)