Fix GSM 7-bit default alphabet decoding in ANSI IS-637-A

svn path=/trunk/; revision=46687

1 files changed, 27 insertions, 111 deletions

diff --git a/epan/dissectors/packet-ansi_637.c b/epan/dissectors/packet-ansi_637.c
index 8a1eff4956..aaf817149f 100644
--- a/epan/dissectors/packet-ansi_637.c
+++ b/epan/dissectors/packet-ansi_637.c
@@ -36,6 +36,7 @@
 #include <epan/emem.h>
 #include <epan/strutil.h>
 
+#include "packet-gsm_sms.h"
 
 static const char *ansi_proto_name_tele = "ANSI IS-637-A (SMS) Teleservice Layer";
 static const char *ansi_proto_name_trans = "ANSI IS-637-A (SMS) Transport Layer";
@@ -183,6 +184,7 @@ static int hf_ansi_637_tele_msg_id = -1;
 static int hf_ansi_637_tele_msg_status = -1;
 static int hf_ansi_637_tele_msg_rsvd = -1;
 static int hf_ansi_637_tele_subparam_id = -1;
+static int hf_ansi_637_tele_user_data_text = -1;
 static int hf_ansi_637_trans_msg_type = -1;
 static int hf_ansi_637_trans_param_id = -1;
 
@@ -201,101 +203,6 @@ static packet_info *g_pinfo;
 static proto_tree *g_tree;
 
 /* FUNCTIONS */
-#define GN_CHAR_ALPHABET_SIZE 128
-
-#define GN_CHAR_ESCAPE 0x1b
-
-static gunichar gsm_default_alphabet[GN_CHAR_ALPHABET_SIZE] = {
-
-    /* ETSI GSM 03.38, version 6.0.1, section 6.2.1; Default alphabet */
-    /* Fixed to use unicode */
-    /* Characters in hex position 10, [12 to 1a] and 24 are not present on
-       latin1 charset, so we cannot reproduce on the screen, however they are
-       greek symbol not present even on my Nokia */
-
-    '@',  0xa3, '$' , 0xa5, 0xe8, 0xe9, 0xf9, 0xec,
-    0xf2, 0xc7, '\n', 0xd8, 0xf8, '\r', 0xc5, 0xe5,
-   0x394, '_', 0x3a6,0x393,0x39b,0x3a9,0x3a0,0x3a8,
-   0x3a3,0x398,0x39e, 0xa0, 0xc6, 0xe6, 0xdf, 0xc9,
-    ' ',  '!',  '\"', '#',  0xa4,  '%',  '&',  '\'',
-    '(',  ')',  '*',  '+',  ',',  '-',  '.',  '/',
-    '0',  '1',  '2',  '3',  '4',  '5',  '6',  '7',
-    '8',  '9',  ':',  ';',  '<',  '=',  '>',  '?',
-    0xa1, 'A',  'B',  'C',  'D',  'E',  'F',  'G',
-    'H',  'I',  'J',  'K',  'L',  'M',  'N',  'O',
-    'P',  'Q',  'R',  'S',  'T',  'U',  'V',  'W',
-    'X',  'Y',  'Z',  0xc4, 0xd6, 0xd1, 0xdc, 0xa7,
-    0xbf, 'a',  'b',  'c',  'd',  'e',  'f',  'g',
-    'h',  'i',  'j',  'k',  'l',  'm',  'n',  'o',
-    'p',  'q',  'r',  's',  't',  'u',  'v',  'w',
-    'x',  'y',  'z',  0xe4, 0xf6, 0xf1, 0xfc, 0xe0
-};
-
-
-
-static gboolean
-char_is_escape(unsigned char value)
-{
-    return (value == GN_CHAR_ESCAPE);
-}
-
-static gunichar
-char_def_alphabet_ext_decode(unsigned char value)
-{
-    switch (value)
-    {
-    case 0x0a: return 0x0c; /* form feed */
-    case 0x14: return '^';
-    case 0x28: return '{';
-    case 0x29: return '}';
-    case 0x2f: return '\\';
-    case 0x3c: return '[';
-    case 0x3d: return '~';
-    case 0x3e: return ']';
-    case 0x40: return '|';
-    case 0x65: return 0x20ac; /* euro */
-    default: return '?'; /* invalid character */
-    }
-}
-
-static gunichar
-char_def_alphabet_decode(unsigned char value)
-{
-    if (value < GN_CHAR_ALPHABET_SIZE)
-    {
-	return gsm_default_alphabet[value];
-    }
-    else
-    {
-	return '?';
-    }
-}
-
-static void
-gsm_sms_char_7bit_ascii_decode(unsigned char * dest, const unsigned char* src, int len)
-{
-    int i, j;
-    gunichar buf;
-
-
-    for (i = 0, j = 0; j < len;  j++)
-    {
-	if (char_is_escape(src[j])) {
-	    buf = char_def_alphabet_ext_decode(src[++j]);
-	    i += g_unichar_to_utf8(buf,&(dest[i]));
-	}
-	else {
-	    buf = char_def_alphabet_decode(src[j]);
-	    i += g_unichar_to_utf8(buf,&(dest[i]));
-	}
-    }
-    dest[i]=0;
-    return;
-}
-
-
-
-
 
 static int
 decode_7_bits(tvbuff_t *tvb, guint32 *offset, guint8 num_fields, guint8 *last_oct, guint8 *last_bit, gchar *buf)
@@ -661,9 +568,8 @@ tele_param_user_data(tvbuff_t *tvb, proto_tree *tree, guint len, guint32 offset)
 
 	decode_7_bits(tvb, &offset, num_fields, &oct, &bit, ansi_637_bigbuf);
 
-	proto_tree_add_text(tree, tvb, saved_offset, offset - saved_offset,
-	    "Encoded user data: %s",
-	    ansi_637_bigbuf);
+	proto_tree_add_unicode_string(tree, hf_ansi_637_tele_user_data_text, tvb, saved_offset,
+	                              offset - saved_offset, ansi_637_bigbuf);
 
 	switch (bit)
 	{
@@ -703,9 +609,9 @@ tele_param_user_data(tvbuff_t *tvb, proto_tree *tree, guint len, guint32 offset)
         out_len = decode_7_bits(tvb, &offset, num_fields, &oct, &bit, ansi_637_bigbuf);
         IA5_7BIT_decode(ia5_637_bigbuf, ansi_637_bigbuf, out_len);
 
-        proto_tree_add_text(tree, tvb, saved_offset, offset - saved_offset,
-                            "Encoded user data: %s",
-                            ia5_637_bigbuf);
+        proto_tree_add_unicode_string(tree, hf_ansi_637_tele_user_data_text, tvb, saved_offset,
+                                      offset - saved_offset, ia5_637_bigbuf);
+
     }
     /*TODO UCS else if (encoding == 0x04)
       {
@@ -726,7 +632,8 @@ tele_param_user_data(tvbuff_t *tvb, proto_tree *tree, guint len, guint32 offset)
             utf8_text = g_convert_with_iconv(tvb_get_ptr(tvb, offset, num_fields), num_fields , cd , NULL , NULL , &l_conv_error);
             if(!l_conv_error)
             {
-                proto_tree_add_text(tree, tvb, offset, num_fields, "Encoded user data: %s", utf8_text);
+                proto_tree_add_unicode_string(tree, hf_ansi_637_tele_user_data_text, tvb, offset,
+                                              num_fields, utf8_text);
             }
             else
             {
@@ -753,7 +660,8 @@ tele_param_user_data(tvbuff_t *tvb, proto_tree *tree, guint len, guint32 offset)
             utf8_text = g_convert_with_iconv(ansi_637_bigbuf , num_fields , cd , NULL , NULL , &l_conv_error);
             if(!l_conv_error)
             {
-                proto_tree_add_text(tree, tvb, offset, num_fields, "Encoded user data: %s", utf8_text);
+                proto_tree_add_unicode_string(tree, hf_ansi_637_tele_user_data_text, tvb, offset,
+                                              num_fields, utf8_text);
             }
             else
             {
@@ -778,16 +686,20 @@ tele_param_user_data(tvbuff_t *tvb, proto_tree *tree, guint len, guint32 offset)
             return;
         }
 
-        bit = 3;
-        saved_offset = offset;
-        out_len = decode_7_bits(tvb, &offset, num_fields, &oct, &bit, ansi_637_bigbuf);
-        gsm_sms_char_7bit_ascii_decode(gsm_637_bigbuf, ansi_637_bigbuf, out_len);
-
-        proto_tree_add_text(tree, tvb, saved_offset, offset - saved_offset,
-                            "Encoded user data: %s",
-                            gsm_637_bigbuf);
+        saved_offset = offset - 1;
+        for (i=0; i < required_octs; i++)
+        {
+            oct = tvb_get_guint8(tvb, saved_offset);
+            oct2 = tvb_get_guint8(tvb, saved_offset + 1);
+            ansi_637_bigbuf[i] = ((oct & 0x07) << 5) | ((oct2 & 0xf8) >> 3);
+            saved_offset++;
+        }
 
+        out_len = gsm_sms_char_7bit_unpack(0, required_octs+1, num_fields, ansi_637_bigbuf, gsm_637_bigbuf);
+        gsm_637_bigbuf[out_len] = '\0';
 
+        proto_tree_add_unicode_string(tree, hf_ansi_637_tele_user_data_text, tvb, offset,
+                                      required_octs, gsm_sms_chars_to_utf8(gsm_637_bigbuf, num_fields));
     }
     else
     {
@@ -2256,6 +2168,10 @@ proto_register_ansi_637(void)
 	    { "Teleservice Subparam ID", "ansi_637_tele.subparam_id",
 	    FT_UINT8, BASE_DEC, VALS(ansi_tele_param_strings), 0,
 	    NULL, HFILL }},
+	{ &hf_ansi_637_tele_user_data_text,
+	    { "Encoded user data", "ansi_637_tele.user_data.text",
+	    FT_STRING, BASE_NONE, NULL, 0,
+	    NULL, HFILL }},
     };
 
     /* Setup protocol subtree array */