Pull get_unicode_or_ascii_string() into packet-smb.c.

Nobody else needs its extra stuff, as they're not pulling data out of an
SMB byte buffer, so they don't need the extra length check, and nobody
else uses it - or should use it, as we now have support for string
encodings in the tvbuff and protocol-tree code.

Change-Id: I8d249ea2c89a744eef12a05ad755811c07ca463a
Reviewed-on: https://code.wireshark.org/review/33581
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>

3 files changed, 157 insertions, 160 deletions

diff --git a/epan/dissectors/packet-smb-common.c b/epan/dissectors/packet-smb-common.c
index e99e74f853..775882b17d 100644
--- a/epan/dissectors/packet-smb-common.c
+++ b/epan/dissectors/packet-smb-common.c
@@ -127,162 +127,6 @@ int dissect_ms_compressed_string(tvbuff_t *tvb, proto_tree *tree, int offset, in
 	return offset + compr_len;
 }
 
-/* Turn a little-endian Unicode '\0'-terminated string into a string we
-   can display.
-   XXX - for now, we just handle the ISO 8859-1 characters.
-   If exactlen==TRUE then us_lenp contains the exact len of the string in
-   bytes. It might not be null terminated !
-   bc specifies the number of bytes in the byte parameters; Windows 2000,
-   at least, appears, in some cases, to put only 1 byte of 0 at the end
-   of a Unicode string if the byte count
-*/
-static gchar *
-unicode_to_str(tvbuff_t *tvb, int offset, int *us_lenp, gboolean exactlen,
-	       guint16 bc)
-{
-	gchar    *cur;
-	gchar    *p;
-	guint16   uchar;
-	int       len;
-	int       us_len;
-	gboolean  overflow = FALSE;
-
-	cur=(gchar *)wmem_alloc(wmem_packet_scope(), MAX_UNICODE_STR_LEN+3+1);
-	p = cur;
-	len = MAX_UNICODE_STR_LEN;
-	us_len = 0;
-	for (;;) {
-		if (bc == 0)
-			break;
-
-		if (bc == 1) {
-			/* XXX - explain this */
-			if (!exactlen)
-				us_len += 1;	/* this is a one-byte null terminator */
-			break;
-		}
-
-		uchar = tvb_get_letohs(tvb, offset);
-		if (uchar == 0) {
-			us_len += 2;	/* this is a two-byte null terminator */
-			break;
-		}
-
-		if (len > 0) {
-			if ((uchar & 0xFF00) == 0)
-				*p++ = (gchar) uchar;	/* ISO 8859-1 */
-			else
-				*p++ = '?';	/* not 8859-1 */
-			len--;
-		} else
-			overflow = TRUE;
-
-		offset += 2;
-		bc -= 2;
-		us_len += 2;
-
-		if(exactlen){
-			if(us_len>= *us_lenp){
-				break;
-			}
-		}
-	}
-	if (overflow) {
-		/* Note that we're not showing the full string.  */
-		*p++ = '.';
-		*p++ = '.';
-		*p++ = '.';
-	}
-
-	*p = '\0';
-	*us_lenp = us_len;
-
-	return cur;
-}
-
-/* nopad == TRUE : Do not add any padding before this string
- * exactlen == TRUE : len contains the exact len of the string in bytes.
- * bc: pointer to variable with amount of data left in the byte parameters
- *   region
- */
-const gchar *
-get_unicode_or_ascii_string(tvbuff_t *tvb, int *offsetp,
-			    gboolean useunicode, int *len, gboolean nopad, gboolean exactlen,
-			    guint16 *bcp)
-{
-	gchar       *cur;
-	const gchar *string;
-	int          string_len = 0;
-	int          copylen;
-	gboolean     overflow   = FALSE;
-
-	if (*bcp == 0) {
-		/* Not enough data in buffer */
-		return NULL;
-	}
-
-	if (useunicode) {
-		if ((!nopad) && (*offsetp % 2)) {
-			(*offsetp)++;   /* Looks like a pad byte there sometimes */
-			(*bcp)--;
-
-			if (*bcp == 0) {
-				/* Not enough data in buffer */
-				return NULL;
-			}
-		}
-
-		if(exactlen){
-			string_len = *len;
-			if (string_len < 0) {
-				/* This probably means it's a very large unsigned number; just set
-				   it to the largest signed number, so that we throw the appropriate
-				   exception. */
-				string_len = INT_MAX;
-			}
-		}
-
-		string = unicode_to_str(tvb, *offsetp, &string_len, exactlen, *bcp);
-
-	} else {
-		if(exactlen){
-			/*
-			 * The string we return must be null-terminated.
-			 */
-			cur=(gchar *)wmem_alloc(wmem_packet_scope(), MAX_UNICODE_STR_LEN+3+1);
-			copylen = *len;
-
-			if (copylen < 0) {
-				/* This probably means it's a very large unsigned number; just set
-				   it to the largest signed number, so that we throw the appropriate
-				   exception. */
-				copylen = INT_MAX;
-			}
-
-			tvb_ensure_bytes_exist(tvb, *offsetp, copylen);
-
-			if (copylen > MAX_UNICODE_STR_LEN) {
-				copylen = MAX_UNICODE_STR_LEN;
-				overflow = TRUE;
-			}
-
-			tvb_memcpy(tvb, (guint8 *)cur, *offsetp, copylen);
-			cur[copylen] = '\0';
-
-			if (overflow)
-				g_strlcat(cur, "...",MAX_UNICODE_STR_LEN+3+1);
-
-			string_len = *len;
-			string = cur;
-		} else {
-			string = tvb_get_const_stringz(tvb, *offsetp, &string_len);
-		}
-	}
-
-	*len = string_len;
-	return string;
-}
-
 /*
  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
  *
diff --git a/epan/dissectors/packet-smb-common.h b/epan/dissectors/packet-smb-common.h
index 4b5500750d..7de2a8a2bf 100644
--- a/epan/dissectors/packet-smb-common.h
+++ b/epan/dissectors/packet-smb-common.h
@@ -25,10 +25,6 @@ int display_ms_string(tvbuff_t *tvb, proto_tree *tree, int offset, int hf_index,
 int dissect_ms_compressed_string(tvbuff_t *tvb, proto_tree *tree, int offset, int hf_index,
 				 const char **data);
 
-const gchar *get_unicode_or_ascii_string(tvbuff_t *tvb, int *offsetp,
-    gboolean useunicode, int *len, gboolean nopad, gboolean exactlen,
-    guint16 *bcp);
-
 extern const value_string share_type_vals[];
 
 #endif
diff --git a/epan/dissectors/packet-smb.c b/epan/dissectors/packet-smb.c
index b2a9c98c88..6d0fc69f63 100644
--- a/epan/dissectors/packet-smb.c
+++ b/epan/dissectors/packet-smb.c
@@ -1718,7 +1718,164 @@ static GSList *conv_tables = NULL;
    End of request/response matching functions
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
 
+/* Max string length for displaying Unicode strings.  */
+#define	MAX_UNICODE_STR_LEN	256
+
+/* Turn a little-endian Unicode '\0'-terminated string into a string we
+   can display.
+   XXX - for now, we just handle the ISO 8859-1 characters.
+   If exactlen==TRUE then us_lenp contains the exact len of the string in
+   bytes. It might not be null terminated !
+   bc specifies the number of bytes in the byte parameters; Windows 2000,
+   at least, appears, in some cases, to put only 1 byte of 0 at the end
+   of a Unicode string if the byte count
+*/
+static gchar *
+unicode_to_str(tvbuff_t *tvb, int offset, int *us_lenp, gboolean exactlen,
+	       guint16 bc)
+{
+	gchar    *cur;
+	gchar    *p;
+	guint16   uchar;
+	int       len;
+	int       us_len;
+	gboolean  overflow = FALSE;
+
+	cur=(gchar *)wmem_alloc(wmem_packet_scope(), MAX_UNICODE_STR_LEN+3+1);
+	p = cur;
+	len = MAX_UNICODE_STR_LEN;
+	us_len = 0;
+	for (;;) {
+		if (bc == 0)
+			break;
+
+		if (bc == 1) {
+			/* XXX - explain this */
+			if (!exactlen)
+				us_len += 1;	/* this is a one-byte null terminator */
+			break;
+		}
+
+		uchar = tvb_get_letohs(tvb, offset);
+		if (uchar == 0) {
+			us_len += 2;	/* this is a two-byte null terminator */
+			break;
+		}
 
+		if (len > 0) {
+			if ((uchar & 0xFF00) == 0)
+				*p++ = (gchar) uchar;	/* ISO 8859-1 */
+			else
+				*p++ = '?';	/* not 8859-1 */
+			len--;
+		} else
+			overflow = TRUE;
+
+		offset += 2;
+		bc -= 2;
+		us_len += 2;
+
+		if(exactlen){
+			if(us_len>= *us_lenp){
+				break;
+			}
+		}
+	}
+	if (overflow) {
+		/* Note that we're not showing the full string.  */
+		*p++ = '.';
+		*p++ = '.';
+		*p++ = '.';
+	}
+
+	*p = '\0';
+	*us_lenp = us_len;
+
+	return cur;
+}
+
+/* nopad == TRUE : Do not add any padding before this string
+ * exactlen == TRUE : len contains the exact len of the string in bytes.
+ * bc: pointer to variable with amount of data left in the byte parameters
+ *   region
+ */
+const gchar *
+get_unicode_or_ascii_string(tvbuff_t *tvb, int *offsetp,
+			    gboolean useunicode, int *len, gboolean nopad, gboolean exactlen,
+			    guint16 *bcp)
+{
+	gchar       *cur;
+	const gchar *string;
+	int          string_len = 0;
+	int          copylen;
+	gboolean     overflow   = FALSE;
+
+	if (*bcp == 0) {
+		/* Not enough data in buffer */
+		return NULL;
+	}
+
+	if (useunicode) {
+		if ((!nopad) && (*offsetp % 2)) {
+			(*offsetp)++;   /* Looks like a pad byte there sometimes */
+			(*bcp)--;
+
+			if (*bcp == 0) {
+				/* Not enough data in buffer */
+				return NULL;
+			}
+		}
+
+		if(exactlen){
+			string_len = *len;
+			if (string_len < 0) {
+				/* This probably means it's a very large unsigned number; just set
+				   it to the largest signed number, so that we throw the appropriate
+				   exception. */
+				string_len = INT_MAX;
+			}
+		}
+
+		string = unicode_to_str(tvb, *offsetp, &string_len, exactlen, *bcp);
+
+	} else {
+		if(exactlen){
+			/*
+			 * The string we return must be null-terminated.
+			 */
+			cur=(gchar *)wmem_alloc(wmem_packet_scope(), MAX_UNICODE_STR_LEN+3+1);
+			copylen = *len;
+
+			if (copylen < 0) {
+				/* This probably means it's a very large unsigned number; just set
+				   it to the largest signed number, so that we throw the appropriate
+				   exception. */
+				copylen = INT_MAX;
+			}
+
+			tvb_ensure_bytes_exist(tvb, *offsetp, copylen);
+
+			if (copylen > MAX_UNICODE_STR_LEN) {
+				copylen = MAX_UNICODE_STR_LEN;
+				overflow = TRUE;
+			}
+
+			tvb_memcpy(tvb, (guint8 *)cur, *offsetp, copylen);
+			cur[copylen] = '\0';
+
+			if (overflow)
+				g_strlcat(cur, "...",MAX_UNICODE_STR_LEN+3+1);
+
+			string_len = *len;
+			string = cur;
+		} else {
+			string = tvb_get_const_stringz(tvb, *offsetp, &string_len);
+		}
+	}
+
+	*len = string_len;
+	return string;
+}
 
 typedef struct _smb_uid_t {
 	char *domain;