1 /*!
2 * ws: a node.js websocket client
3 * Copyright(c) 2011 Einar Otto Stangvik <einaros@gmail.com>
4 * MIT Licensed
5 */
6
7 #include <v8.h>
8 #include <node.h>
9 #include <node_buffer.h>
10 #include <node_object_wrap.h>
11 #include <stdlib.h>
12 #include <wchar.h>
13 #include <stdio.h>
14 #include "nan.h"
15
16 using namespace v8;
17 using namespace node;
18
19 #define UNI_SUR_HIGH_START (uint32_t) 0xD800
20 #define UNI_SUR_LOW_END (uint32_t) 0xDFFF
21 #define UNI_REPLACEMENT_CHAR (uint32_t) 0x0000FFFD
22 #define UNI_MAX_LEGAL_UTF32 (uint32_t) 0x0010FFFF
23
24 static const uint8_t trailingBytesForUTF8[256] = {
25 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
26 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
27 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
28 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
29 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
30 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
31 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
32 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5
33 };
34
35 static const uint32_t offsetsFromUTF8[6] = {
36 0x00000000, 0x00003080, 0x000E2080,
37 0x03C82080, 0xFA082080, 0x82082080
38 };
39
isLegalUTF8(const uint8_t * source,const int length)40 static int isLegalUTF8(const uint8_t *source, const int length)
41 {
42 uint8_t a;
43 const uint8_t *srcptr = source+length;
44 switch (length) {
45 default: return 0;
46 /* Everything else falls through when "true"... */
47 /* RFC3629 makes 5 & 6 bytes UTF-8 illegal
48 case 6: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return 0;
49 case 5: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return 0; */
50 case 4: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return 0;
51 case 3: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return 0;
52 case 2: if ((a = (*--srcptr)) > 0xBF) return 0;
53 switch (*source) {
54 /* no fall-through in this inner switch */
55 case 0xE0: if (a < 0xA0) return 0; break;
56 case 0xED: if (a > 0x9F) return 0; break;
57 case 0xF0: if (a < 0x90) return 0; break;
58 case 0xF4: if (a > 0x8F) return 0; break;
59 default: if (a < 0x80) return 0;
60 }
61
62 case 1: if (*source >= 0x80 && *source < 0xC2) return 0;
63 }
64 if (*source > 0xF4) return 0;
65 return 1;
66 }
67
is_valid_utf8(size_t len,char * value)68 int is_valid_utf8 (size_t len, char *value)
69 {
70 /* is the string valid UTF-8? */
71 for (unsigned int i = 0; i < len; i++) {
72 uint32_t ch = 0;
73 uint8_t extrabytes = trailingBytesForUTF8[(uint8_t) value[i]];
74
75 if (extrabytes + i >= len)
76 return 0;
77
78 if (isLegalUTF8 ((uint8_t *) (value + i), extrabytes + 1) == 0) return 0;
79
80 switch (extrabytes) {
81 case 5 : ch += (uint8_t) value[i++]; ch <<= 6;
82 case 4 : ch += (uint8_t) value[i++]; ch <<= 6;
83 case 3 : ch += (uint8_t) value[i++]; ch <<= 6;
84 case 2 : ch += (uint8_t) value[i++]; ch <<= 6;
85 case 1 : ch += (uint8_t) value[i++]; ch <<= 6;
86 case 0 : ch += (uint8_t) value[i];
87 }
88
89 ch -= offsetsFromUTF8[extrabytes];
90
91 if (ch <= UNI_MAX_LEGAL_UTF32) {
92 if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END)
93 return 0;
94 } else {
95 return 0;
96 }
97 }
98
99 return 1;
100 }
101
102 class Validation : public ObjectWrap
103 {
104 public:
105
Initialize(v8::Handle<v8::Object> target)106 static void Initialize(v8::Handle<v8::Object> target)
107 {
108 NanScope();
109 Local<FunctionTemplate> t = NanNew<FunctionTemplate>(New);
110 t->InstanceTemplate()->SetInternalFieldCount(1);
111 NODE_SET_METHOD(t, "isValidUTF8", Validation::IsValidUTF8);
112 target->Set(NanSymbol("Validation"), t->GetFunction());
113 }
114
115 protected:
116
NAN_METHOD(New)117 static NAN_METHOD(New)
118 {
119 NanScope();
120 Validation* validation = new Validation();
121 validation->Wrap(args.This());
122 NanReturnValue(args.This());
123 }
124
NAN_METHOD(IsValidUTF8)125 static NAN_METHOD(IsValidUTF8)
126 {
127 NanScope();
128 if (!Buffer::HasInstance(args[0])) {
129 return NanThrowTypeError("First argument needs to be a buffer");
130 }
131 Local<Object> buffer_obj = args[0]->ToObject();
132 char *buffer_data = Buffer::Data(buffer_obj);
133 size_t buffer_length = Buffer::Length(buffer_obj);
134 NanReturnValue(is_valid_utf8(buffer_length, buffer_data) == 1 ? NanTrue() : NanFalse());
135 }
136 };
137
init(Handle<Object> target)138 extern "C" void init (Handle<Object> target)
139 {
140 NanScope();
141 Validation::Initialize(target);
142 }
143
144 NODE_MODULE(validation, init)
145
146