Clean up handling of the command parameter.

It's an unsigned int, as per the protocol spec.  Treat it as such.  (Add
a URL for the protocol spec while we're at it.)

Convert it from a string of ASCII hex digits to a number using
ws_hexstrtou32(); that routine does the appropriate checks.

Clean up blank lines while we're at it - add some and remove some.

Change-Id: I2c0832c4a57c121e2e64de49a8678b747025f35e
Reviewed-on: https://code.wireshark.org/review/33972
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 35 insertions, 36 deletions

diff --git a/epan/dissectors/packet-distcc.c b/epan/dissectors/packet-distcc.c
index fe4594afd3..a36502bed8 100644
--- a/epan/dissectors/packet-distcc.c
+++ b/epan/dissectors/packet-distcc.c
@@ -9,16 +9,20 @@
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
-/* This dissector supports version 1 of the DISTCC protocol */
 
-#include "config.h"
+/*
+ * This dissector supports version 1 of the DISTCC protocol:
+ *
+ *    https://github.com/distcc/distcc/blob/master/doc/protocol-1.txt
+ */
 
-#include <stdio.h>
+#include "config.h"
 
 #include <epan/packet.h>
 #include <epan/expert.h>
 #include <epan/prefs.h>
 
+#include <wsutil/strtoi.h>
 
 static int proto_distcc = -1;
 static int hf_distcc_version = -1;
@@ -45,7 +49,7 @@ void proto_register_distcc(void);
 extern void proto_reg_handoff_distcc(void);
 
 #define CHECK_PDU_LEN(x) \
-    if(parameter>tvb_captured_length_remaining(tvb, offset) || parameter < 1){\
+    if(parameter>(guint)tvb_captured_length_remaining(tvb, offset) || parameter < 1){\
         len=tvb_captured_length_remaining(tvb, offset);\
         col_append_str(pinfo->cinfo, COL_INFO, "[Short" x " PDU]");\
     } \
@@ -56,7 +60,7 @@ extern void proto_reg_handoff_distcc(void);
     if(distcc_desegment && pinfo->can_desegment){\
         /* only attempt reassembly if we have the full segment */\
         if(tvb_captured_length_remaining(tvb, offset)==tvb_reported_length_remaining(tvb, offset)){\
-            if(parameter>tvb_captured_length_remaining(tvb, offset)){\
+            if(parameter>(guint)tvb_captured_length_remaining(tvb, offset)){\
                 proto_tree_add_expert_format(tree, pinfo, &ei_distcc_short_pdu, tvb, offset-12, -1, "[Short " x " PDU]");\
                 pinfo->desegment_offset=offset-12;\
                 pinfo->desegment_len=parameter-tvb_captured_length_remaining(tvb, offset);\
@@ -65,16 +69,12 @@ extern void proto_reg_handoff_distcc(void);
         }\
     }
 
-
-
-
-
 static int
 dissect_distcc_dist(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint32 parameter)
 {
-    proto_tree_add_uint_format(tree, hf_distcc_version, tvb, offset-12, 12, parameter, "DIST: %d", parameter);
+    proto_tree_add_uint_format(tree, hf_distcc_version, tvb, offset-12, 12, parameter, "DIST: %u", parameter);
 
-    col_append_fstr(pinfo->cinfo, COL_INFO, "DIST:%d ", parameter);
+    col_append_fstr(pinfo->cinfo, COL_INFO, "DIST:%u ", parameter);
 
     return offset;
 }
@@ -82,9 +82,9 @@ dissect_distcc_dist(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
 static int
 dissect_distcc_done(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint32 parameter)
 {
-    proto_tree_add_uint_format(tree, hf_distcc_version, tvb, offset-12, 12, parameter, "DONE: %d", parameter);
+    proto_tree_add_uint_format(tree, hf_distcc_version, tvb, offset-12, 12, parameter, "DONE: %u", parameter);
 
-    col_append_fstr(pinfo->cinfo, COL_INFO, "DONE:%d ", parameter);
+    col_append_fstr(pinfo->cinfo, COL_INFO, "DONE:%u ", parameter);
 
     return offset;
 }
@@ -92,9 +92,9 @@ dissect_distcc_done(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
 static int
 dissect_distcc_stat(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint32 parameter)
 {
-    proto_tree_add_uint_format(tree, hf_distcc_stat, tvb, offset-12, 12, parameter, "STAT: %d", parameter);
+    proto_tree_add_uint_format(tree, hf_distcc_stat, tvb, offset-12, 12, parameter, "STAT: %u", parameter);
 
-    col_append_fstr(pinfo->cinfo, COL_INFO, "STAT:%d ", parameter);
+    col_append_fstr(pinfo->cinfo, COL_INFO, "STAT:%u ", parameter);
 
     return offset;
 }
@@ -104,17 +104,17 @@ dissect_distcc_argc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
 {
     proto_tree_add_uint(tree, hf_distcc_argc, tvb, offset-12, 12, parameter);
 
-    col_append_fstr(pinfo->cinfo, COL_INFO, "ARGC:%d ", parameter);
+    col_append_fstr(pinfo->cinfo, COL_INFO, "ARGC:%u ", parameter);
 
     return offset;
 }
 
 static int
-dissect_distcc_argv(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, gint parameter)
+dissect_distcc_argv(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint parameter)
 {
     char argv[256];
     int argv_len;
-    gint len=parameter;
+    gint len=(gint)parameter;
     proto_item* ti;
 
     CHECK_PDU_LEN("ARGV");
@@ -130,18 +130,18 @@ dissect_distcc_argv(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
 
     col_append_fstr(pinfo->cinfo, COL_INFO, "%s ", argv);
 
-    if(len!=parameter){
+    if(len!=(gint)parameter){
         expert_add_info_format(pinfo, ti, &ei_distcc_short_pdu, "[Short ARGV PDU]");
     }
     return offset+len;
 }
 
 static int
-dissect_distcc_serr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, gint parameter)
+dissect_distcc_serr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint parameter)
 {
     char argv[256];
     int argv_len;
-    gint len=parameter;
+    gint len=(gint)parameter;
     proto_item* ti;
 
     CHECK_PDU_LEN("SERR");
@@ -149,8 +149,6 @@ dissect_distcc_serr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
     /* see if we need to desegment the PDU */
     DESEGMENT_TCP("SERR");
 
-
-
     argv_len=len>255?255:len;
     tvb_memcpy(tvb, argv, offset, argv_len);
     argv[argv_len]=0;
@@ -159,18 +157,18 @@ dissect_distcc_serr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
 
     col_append_fstr(pinfo->cinfo, COL_INFO, "SERR:%s ", argv);
 
-    if(len!=parameter){
+    if(len!=(gint)parameter){
         expert_add_info_format(pinfo, ti, &ei_distcc_short_pdu, "[Short SERR PDU]");
     }
     return offset+len;
 }
 
 static int
-dissect_distcc_sout(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, gint parameter)
+dissect_distcc_sout(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint parameter)
 {
     char argv[256];
     int argv_len;
-    gint len=parameter;
+    gint len=(gint)parameter;
     proto_item* ti;
 
     CHECK_PDU_LEN("SOUT");
@@ -186,7 +184,7 @@ dissect_distcc_sout(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
 
     col_append_fstr(pinfo->cinfo, COL_INFO, "SOUT:%s ", argv);
 
-    if(len!=parameter){
+    if(len!=(gint)parameter){
         expert_add_info_format(pinfo, ti, &ei_distcc_short_pdu, "[Short SOUT PDU]");
     }
     return offset+len;
@@ -194,9 +192,9 @@ dissect_distcc_sout(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
 
 
 static int
-dissect_distcc_doti(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, gint parameter)
+dissect_distcc_doti(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint parameter)
 {
-    gint len=parameter;
+    gint len=(gint)parameter;
     proto_item* ti;
 
     CHECK_PDU_LEN("DOTI");
@@ -207,19 +205,19 @@ dissect_distcc_doti(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
     col_append_str(pinfo->cinfo, COL_INFO, "DOTI source ");
 
     ti = proto_tree_add_item(tree, hf_distcc_doti_source, tvb, offset, len, ENC_ASCII|ENC_NA);
-    if(len!=parameter){
+
+    if(len!=(gint)parameter){
         expert_add_info_format(pinfo, ti, &ei_distcc_short_pdu, "[Short DOTI PDU]");
     }
     return offset+len;
 }
 
 static int
-dissect_distcc_doto(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, gint parameter)
+dissect_distcc_doto(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint parameter)
 {
-    gint len=parameter;
+    gint len=(gint)parameter;
     proto_item* ti;
 
-
     CHECK_PDU_LEN("DOTO");
 
     /* see if we need to desegment the PDU */
@@ -228,7 +226,8 @@ dissect_distcc_doto(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int off
     col_append_str(pinfo->cinfo, COL_INFO, "DOTO object ");
 
     ti = proto_tree_add_item(tree, hf_distcc_doto_object, tvb, offset, len, ENC_NA);
-    if(len!=parameter){
+
+    if(len!=(gint)parameter){
         expert_add_info_format(pinfo, ti, &ei_distcc_short_pdu, "[Short DOTO PDU]");
     }
     return offset+len;
@@ -263,8 +262,8 @@ dissect_distcc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void*
         buf[12] = '\0';
         offset+=12;
 
-        /* scan the parameter */
-        if (sscanf(buf + 4, "%08x", &parameter) != 1)
+        /* get the parameter value */
+        if (!ws_hexstrtou32(buf + 4, NULL, &parameter))
             return offset;
 
         if(!strncmp(buf, "DIST", 4)){