Load signatures with incompatible fast_pattern option (due to design differences for optimization)

src/detect-fast-pattern.c

@@ -74,9 +74,13 @@ static int DetectFastPatternSetup(DetectEngineCtx *de_ctx, Signature *s, char *n
     }
 
     if (s->pmatch_tail == NULL) {
-        SCLogError(SC_ERR_INVALID_SIGNATURE, "fast_pattern found inside the "
-                     "rule, without any preceding keywords");
-        return -1;
+        SCLogWarning(SC_WARN_COMPATIBILITY, " a fast_pattern found inside the "
+                     "rule, is not preceding a keyword that support (currently)"
+                     " this optimization. At least, the engine support "
+                     "fast_pattern for content (not for uricontent yet). "
+                     "The signature is being loaded anyway ==> %s",
+                     s->sig_str);
+        return 0;
     }
 
     SigMatch *pm = DetectContentGetLastPattern(s->pmatch_tail);

src/detect-parse.c

@@ -912,6 +912,7 @@ int SigParse(DetectEngineCtx *de_ctx, Signature *s, char *sigstr, uint8_t addrs_
     SCEnter();
 
     char **basics;
+    s->sig_str = sigstr;
 
     int ret = SigParseBasics(s, sigstr, &basics, addrs_direction);
     if (ret < 0) {
@@ -944,6 +945,8 @@ int SigParse(DetectEngineCtx *de_ctx, Signature *s, char *sigstr, uint8_t addrs_
         SCFree(basics);
     }
 
+    s->sig_str = NULL;
+
     SCReturnInt(ret);
 }
 

src/detect.h

@@ -312,6 +312,10 @@ typedef struct Signature_ {
     /** Reference */
     Reference *references;
 
+    /* Be careful, this pointer is only valid while parsing the sig,
+     * to warn the user about any possible problem */
+    char *sig_str;
+
 #ifdef PROFILING
     uint16_t profiling_id;
 #endif

src/util-error.c

@@ -187,6 +187,7 @@ const char * SCErrorToString(SCError err)
         CASE_CODE (SC_ERR_ERF_DAG_STREAM_SET_FAILED);
         CASE_CODE (SC_ERR_ERF_DAG_STREAM_READ_FAILED);
         CASE_CODE (SC_WARN_ERF_DAG_REC_LEN_CHANGED);
+        CASE_CODE (SC_WARN_COMPATIBILITY);
         CASE_CODE (SC_ERR_DCERPC);
 
         default:

src/util-error.h

@@ -188,6 +188,7 @@ typedef enum {
     SC_ERR_LIBCAP_NG_REQUIRED,
     SC_ERR_LIBNET11_INCOMPATIBLE_WITH_LIBCAP_NG,
     SC_WARN_FLOW_EMERGENCY,
+    SC_WARN_COMPATIBILITY,
 	SC_ERR_SVC,
     SC_ERR_ERF_DAG_OPEN_FAILED,
     SC_ERR_ERF_DAG_STREAM_OPEN_FAILED,