Added JSON native file support.

libjsmn has also been moved from epan/ to wsutil/ to make it visible from wiretap.

Change-Id: I59abb3419acb1baa83194b38152d3651ed5c123c
Bug: 10878
Reviewed-on: https://code.wireshark.org/review/6716
Reviewed-by: Pascal Quantin <pascal.quantin@gmail.com>

7 files changed, 208 insertions, 0 deletions

diff --git a/wiretap/CMakeLists.txt b/wiretap/CMakeLists.txt
index 1e7ead3ad8..52b3738320 100644
--- a/wiretap/CMakeLists.txt
+++ b/wiretap/CMakeLists.txt
@@ -46,6 +46,7 @@ set(CLEAN_FILES
 	ipfix.c
 	iptrace.c
 	iseries.c
+	json.c
 	k12.c
 	lanalyzer.c
 	libpcap.c
diff --git a/wiretap/Makefile.common b/wiretap/Makefile.common
index f1f30b0352..9bd64db3d4 100644
--- a/wiretap/Makefile.common
+++ b/wiretap/Makefile.common
@@ -52,6 +52,7 @@ NONGENERATED_C_FILES = \
 	iptrace.c		\
 	iseries.c		\
 	mime_file.c		\
+	json.c          \
 	k12.c			\
 	lanalyzer.c		\
 	logcat_text.c		\
diff --git a/wiretap/file_access.c b/wiretap/file_access.c
index 9006e4862c..898f17e078 100644
--- a/wiretap/file_access.c
+++ b/wiretap/file_access.c
@@ -65,6 +65,7 @@
 #include "hcidump.h"
 #include "logcat.h"
 #include "logcat_text.h"
+#include "json.h"
 #include "network_instruments.h"
 #include "k12.h"
 #include "ber.h"
@@ -156,6 +157,7 @@ static const struct file_extension_info file_type_extensions_base[] = {
 	{ "MPEG2 transport stream", "mp2t;ts;mpg" },
 	{ "Ixia IxVeriWave .vwr Raw 802.11 Capture", "vwr" },
 	{ "CAM Inspector file", "camins" },
+	{ "JavaScript Object Notation file", "json" }
 };
 
 #define	N_FILE_TYPE_EXTENSIONS	(sizeof file_type_extensions_base / sizeof file_type_extensions_base[0])
@@ -395,6 +397,7 @@ static struct open_info open_info_base[] = {
 	/* Extremely weak heuristics - put them at the end. */
 	{ "Ixia IxVeriWave .vwr Raw Capture",       OPEN_INFO_HEURISTIC, vwr_open,                 "vwr",      NULL, NULL },
 	{ "CAM Inspector file",                     OPEN_INFO_HEURISTIC, camins_open,              "camins",   NULL, NULL },
+	{ "JavaScript Object Notation",             OPEN_INFO_HEURISTIC, json_open,                "json",     NULL, NULL }
 };
 
 /* this is only used to build the dynamic array on load, do NOT use this
@@ -1488,6 +1491,11 @@ static const struct file_type_subtype_info dump_open_table_base[] = {
 	  FALSE, FALSE, 0,
 	  logcat_dump_can_write_encap, logcat_binary_dump_open, NULL },
 
+	/* WTAP_FILE_TYPE_SUBTYPE_JSON */
+	{ "JavaScript Object Notation", "json", "json", "NULL",
+	  FALSE, FALSE, 0,
+	  NULL, NULL, NULL },
+
 	/* WTAP_FILE_TYPE_SUBTYPE_LOGCAT_BRIEF */
 	{ "Android Logcat Brief text format", "logcat-brief", NULL, NULL,
 	  FALSE, FALSE, 0,
diff --git a/wiretap/json.c b/wiretap/json.c
new file mode 100644
index 0000000000..9e81f2e56d
--- /dev/null
+++ b/wiretap/json.c
@@ -0,0 +1,138 @@
+/* json.c
+ *
+ * Copyright 2015, Dario Lombardo <lomato@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+
+#include <string.h>
+
+#include "wtap-int.h"
+#include "file_wrappers.h"
+
+#include <json.h>
+#include <wsutil/jsmn.h>
+
+static gboolean json_read_file(wtap *wth, FILE_T fh, struct wtap_pkthdr *phdr,
+    Buffer *buf, int *err, gchar **err_info)
+{
+    gint64 file_size;
+    int packet_size;
+
+    if ((file_size = wtap_file_size(wth, err)) == -1)
+        return FALSE;
+
+    if (file_size > MAX_FILE_SIZE) {
+        /*
+         * Don't blow up trying to allocate space for an
+         * immensely-large file.
+         */
+        *err = WTAP_ERR_BAD_FILE;
+        *err_info = g_strdup_printf("mime_file: File has %" G_GINT64_MODIFIER "d-byte packet, bigger than maximum of %u",
+            file_size, MAX_FILE_SIZE);
+        return FALSE;
+    }
+    packet_size = (int)file_size;
+
+    phdr->rec_type = REC_TYPE_PACKET;
+    phdr->presence_flags = 0; /* yes, we have no bananas^Wtime stamp */
+
+    phdr->caplen = packet_size;
+    phdr->len = packet_size;
+
+    phdr->ts.secs = 0;
+    phdr->ts.nsecs = 0;
+
+    return wtap_read_packet_bytes(fh, buf, packet_size, err, err_info);
+}
+
+static gboolean json_seek_read(wtap *wth, gint64 seek_off, struct wtap_pkthdr *phdr, Buffer *buf,
+    int *err, gchar **err_info)
+{
+    /* there is only one packet */
+    if (seek_off > 0) {
+        *err = 0;
+        return FALSE;
+    }
+
+    if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
+        return FALSE;
+
+    return json_read_file(wth, wth->random_fh, phdr, buf, err, err_info);
+}
+
+static gboolean json_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
+{
+    gint64 offset;
+
+    *err = 0;
+
+    offset = file_tell(wth->fh);
+
+    /* there is only ever one packet */
+    if (offset != 0)
+        return FALSE;
+
+    *data_offset = offset;
+
+    return json_read_file(wth, wth->fh, &wth->phdr, wth->frame_buffer, err, err_info);
+}
+
+wtap_open_return_val json_open(wtap *wth, int *err, gchar **err_info _U_)
+{
+    guint8* filebuf;
+    guint read;
+
+    filebuf = (guint8*)g_malloc0(MAX_FILE_SIZE);
+    if (!filebuf)
+        return WTAP_OPEN_ERROR;
+
+    read = file_read(filebuf, MAX_FILE_SIZE, wth->fh);
+
+    if (jsmn_is_json(filebuf, read) == FALSE) {
+        g_free(filebuf);
+        return WTAP_OPEN_NOT_MINE;
+    }
+
+    if (file_seek(wth->fh, 0, SEEK_SET, err) == -1) {
+        g_free(filebuf);
+        return WTAP_OPEN_ERROR;
+    }
+
+    wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_JSON;
+    wth->file_encap = WTAP_ENCAP_JSON;
+    wth->file_tsprec = WTAP_TSPREC_SEC;
+    wth->subtype_read = json_read;
+    wth->subtype_seek_read = json_seek_read;
+    wth->snapshot_length = 0;
+
+    g_free(filebuf);
+    return WTAP_OPEN_MINE;
+}
+
+/*
+ * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */
diff --git a/wiretap/json.h b/wiretap/json.h
new file mode 100644
index 0000000000..8c233cb771
--- /dev/null
+++ b/wiretap/json.h
@@ -0,0 +1,55 @@
+/* json.h
+ *
+ * Copyright 2015, Dario Lombardo <lomato@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef __JSON_H__
+#define __JSON_H__
+
+#include <glib.h>
+
+#include "wtap.h"
+
+/*
+ * Impose a not-too-large limit on the maximum file size, to avoid eating
+ * up 99% of the (address space, swap partition, disk space for swap/page
+ * files); if we were to return smaller chunks and let the dissector do
+ * reassembly, it would *still* have to allocate a buffer the size of
+ * the file, so it's not as if we'd neve try to allocate a buffer the
+ * size of the file.
+ *
+ * For now, go for 50MB.
+ */
+#define MAX_FILE_SIZE	(50*1024*1024)
+
+wtap_open_return_val json_open(wtap *wth, int *err, gchar **err_info);
+
+#endif
+
+/*
+ * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */
diff --git a/wiretap/wtap.c b/wiretap/wtap.c
index 6b0cf92610..4de71ee723 100644
--- a/wiretap/wtap.c
+++ b/wiretap/wtap.c
@@ -740,6 +740,9 @@ static struct encap_type_info encap_table_base[] = {
 
 	/* WTAP_ENCAP_LOOP */
 	{ "OpenBSD loopback", "loop" },
+
+	/* WTAP_ENCAP_JSON */
+	{ "JavaScript Object Notation", "json" }
 };
 
 WS_DLL_LOCAL
diff --git a/wiretap/wtap.h b/wiretap/wtap.h
index 1570466579..f5aaebfa61 100644
--- a/wiretap/wtap.h
+++ b/wiretap/wtap.h
@@ -266,6 +266,7 @@ extern "C" {
 #define WTAP_ENCAP_EPON                         173
 #define WTAP_ENCAP_IPMI_TRACE                   174
 #define WTAP_ENCAP_LOOP                         175
+#define WTAP_ENCAP_JSON                         176
 /* After adding new item here, please also add new item to encap_table_base array */
 
 #define WTAP_NUM_ENCAP_TYPES                    wtap_get_num_encap_types()
@@ -352,6 +353,7 @@ extern "C" {
 #define WTAP_FILE_TYPE_SUBTYPE_LOGCAT_LONG                   74
 #define WTAP_FILE_TYPE_SUBTYPE_COLASOFT_CAPSA                75
 #define WTAP_FILE_TYPE_SUBTYPE_COLASOFT_PACKET_BUILDER       76
+#define WTAP_FILE_TYPE_SUBTYPE_JSON                          77
 
 #define WTAP_NUM_FILE_TYPES_SUBTYPES  wtap_get_num_file_types_subtypes()