Added wrappers for substring-search

ndpi_init_automa()
ndpi_free_automa()
ndpi_add_string_to_automa()
ndpi_finalize_automa()
ndpi_match_string()
set_ndpi_malloc()
set_ndpi_free()

4 files changed, 103 insertions, 4 deletions

diff --git a/src/include/ndpi_api.h b/src/include/ndpi_api.h
index a07c96e63..113aa0ea2 100644
--- a/src/include/ndpi_api.h
+++ b/src/include/ndpi_api.h
@@ -544,6 +544,62 @@ extern "C" {
 		      struct ndpi_flow_struct *flow, char *certificate);
 #endif
 
+  /* Wrappers functions */
+  /**
+   * Init Aho-Corasick automata
+   *
+   * @return  The requested automata, or NULL if an error occurred
+   * 
+   */
+  void* ndpi_init_automa();
+
+
+  /**
+   * Free Aho-Corasick automata allocated with ndpi_init_automa();
+   *
+   * @par     The automata initialized with ndpi_init_automa();
+   * @return  The requested automata, or NULL if an error occurred
+   * 
+   */
+  void ndpi_free_automa(void *_automa);
+
+
+  /**
+   * Add a string to match to an automata
+   *
+   * @par     The automata initialized with ndpi_init_automa();
+   * @par     The (sub)string to search
+   * @return  0 in case of no error, or -1 if an error occurred.
+   * 
+   */
+  int ndpi_add_string_to_automa(void *_automa, char *str);
+
+
+  /**
+   * Finalize the automa (necessary before start searching)
+   *
+   * @par     The automata initialized with ndpi_init_automa();
+   * 
+   */
+  void ndpi_finalize_automa(void *_automa);
+
+
+  /**
+   * Add a string to match to an automata
+   *
+   * @par     The automata initialized with ndpi_init_automa();
+   * @par     The (sub)string to search
+   * @return  0 in case of match, or -1 if no match, or -2 if an error occurred.
+   * 
+   */
+  int ndpi_match_string(void *_automa, char *string_to_match);
+
+
+
+  /* Utility functions to set ndpi malloc/free wrappers */
+  void set_ndpi_malloc(void* (*__ndpi_malloc)(size_t size));
+  void set_ndpi_free(void  (*__ndpi_free)(void *ptr));
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/lib/ndpi_content_match.c.inc b/src/lib/ndpi_content_match.c.inc
index 458ab1a7a..af6215842 100644
--- a/src/lib/ndpi_content_match.c.inc
+++ b/src/lib/ndpi_content_match.c.inc
@@ -7533,3 +7533,4 @@ static const char *ndpi_en_impossible_bigrams[] = {
   "yj", "yq", "yv", "yz", "yw", "zb", "zc", "zg", "zh", "zj", "zn", "zq", "zr", "zs", "zx", "wh", "wk",
   "wb", "zk", "kp", "zk", "xy",
   NULL };
+
diff --git a/src/lib/ndpi_main.c b/src/lib/ndpi_main.c
index 9e8c75c8f..dcc5d8705 100644
--- a/src/lib/ndpi_main.c
+++ b/src/lib/ndpi_main.c
@@ -1681,6 +1681,9 @@ static int ndpi_add_host_ip_subprotocol(struct ndpi_detection_module_struct *ndp
 
 #endif
 
+void set_ndpi_malloc(void* (*__ndpi_malloc)(size_t size)) { _ndpi_malloc = __ndpi_malloc; }
+void set_ndpi_free(void  (*__ndpi_free)(void *ptr))       { _ndpi_free = __ndpi_free; }
+
 /* ******************************************************************** */
 
 struct ndpi_detection_module_struct *ndpi_init_detection_module(u_int32_t ticks_per_second,
@@ -1691,8 +1694,7 @@ struct ndpi_detection_module_struct *ndpi_init_detection_module(u_int32_t ticks_
   struct ndpi_detection_module_struct *ndpi_str;
 
   /* TODO global malloc wrappers should not be set here: ndpi_init_detection_module can be called many times */
-  _ndpi_malloc = __ndpi_malloc;
-  _ndpi_free = __ndpi_free;
+  set_ndpi_malloc(__ndpi_malloc), set_ndpi_free(__ndpi_free);
 
   ndpi_str = ndpi_malloc(sizeof(struct ndpi_detection_module_struct));
 
@@ -1746,6 +1748,47 @@ struct ndpi_detection_module_struct *ndpi_init_detection_module(u_int32_t ticks_
 
 /* *********************************************** */
 
+/* Wrappers */
+void* ndpi_init_automa() {
+  return(ac_automata_init(ac_match_handler));
+}
+
+int ndpi_add_string_to_automa(void *_automa, char *str) { 
+  AC_PATTERN_t ac_pattern;
+  AC_AUTOMATA_t *automa = (AC_AUTOMATA_t*)_automa;
+
+  if(automa == NULL) return(-1);
+
+  ac_pattern.astring = str;
+  ac_pattern.rep.number = 1; /* Dummy */
+  ac_pattern.length = strlen(ac_pattern.astring);
+  return(ac_automata_add(automa, &ac_pattern) == ACERR_SUCCESS ? 0 : -1);
+}
+
+void ndpi_free_automa(void *_automa)     { ac_automata_release((AC_AUTOMATA_t*)_automa);  }
+void ndpi_finalize_automa(void *_automa) { ac_automata_finalize((AC_AUTOMATA_t*)_automa); }
+
+/* ****************************************************** */
+
+int ndpi_match_string(void *_automa, char *string_to_match) {
+  int matching_protocol_id = NDPI_PROTOCOL_UNKNOWN;
+  AC_TEXT_t ac_input_text;
+  AC_AUTOMATA_t *automa = (AC_AUTOMATA_t*)_automa;
+  
+  if((automa == NULL) 
+     || (string_to_match == NULL)
+     || (string_to_match[0] == '\0'))
+    return(-2);
+
+  ac_input_text.astring = string_to_match, ac_input_text.length = strlen(string_to_match);
+  ac_automata_search(automa, &ac_input_text, (void*)&matching_protocol_id);
+  ac_automata_reset(automa);
+
+  return(matching_protocol_id > 0 ? 0 : -1);
+}
+
+/* *********************************************** */
+
 static void free_ptree_data(void *data) { ; }
 
 /* ****************************************************** */
diff --git a/src/lib/protocols/dns.c b/src/lib/protocols/dns.c
index 503761137..c54c62f18 100644
--- a/src/lib/protocols/dns.c
+++ b/src/lib/protocols/dns.c
@@ -117,8 +117,7 @@ void ndpi_search_dns(struct ndpi_detection_module_struct *ndpi_struct, struct nd
       if(off < flow->packet.payload_packet_len)
       {
 	flow->host_server_name[j] = flow->packet.payload[off];
-	if(j < strlen(flow->host_server_name))
-	{
+	if(j < strlen((char*)flow->host_server_name)) {
 	  if(flow->host_server_name[j] < ' ')
 	    flow->host_server_name[j] = '.';
 	  j++;