1  /*
2  * "streamable kanji code filter and converter"
3  * Copyright (c) 1998-2002 HappySize, Inc. All rights reserved.
4  *
5  * LICENSE NOTICES
6  *
7  * This file is part of "streamable kanji code filter and converter",
8  * which is distributed under the terms of GNU Lesser General Public
9  * License (version 2) as published by the Free Software Foundation.
10  *
11  * This software is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with "streamable kanji code filter and converter";
18  * if not, write to the Free Software Foundation, Inc., 59 Temple Place,
19  * Suite 330, Boston, MA  02111-1307  USA
20  *
21  * The author of this file:
22  *
23  */
24 /*
25  * The source code included in this files was separated from mbfilter.c
26  * by Moriyoshi Koizumi <moriyoshi@php.net> on 4 Dec 2002. The file
27  * mbfilter.c is included in this package .
28  *
29  */
30 
31 #include "mbfilter.h"
32 #include "mbfilter_base64.h"
33 
34 const mbfl_encoding mbfl_encoding_base64 = {
35 	mbfl_no_encoding_base64,
36 	"BASE64",
37 	"BASE64",
38 	NULL,
39 	NULL,
40 	MBFL_ENCTYPE_GL_UNSAFE,
41 	NULL,
42 	NULL
43 };
44 
45 const struct mbfl_convert_vtbl vtbl_8bit_b64 = {
46 	mbfl_no_encoding_8bit,
47 	mbfl_no_encoding_base64,
48 	mbfl_filt_conv_common_ctor,
49 	NULL,
50 	mbfl_filt_conv_base64enc,
51 	mbfl_filt_conv_base64enc_flush,
52 	NULL,
53 };
54 
55 const struct mbfl_convert_vtbl vtbl_b64_8bit = {
56 	mbfl_no_encoding_base64,
57 	mbfl_no_encoding_8bit,
58 	mbfl_filt_conv_common_ctor,
59 	NULL,
60 	mbfl_filt_conv_base64dec,
61 	mbfl_filt_conv_base64dec_flush,
62 	NULL,
63 };
64 
65 
66 #define CK(statement)	do { if ((statement) < 0) return (-1); } while (0)
67 
68 /*
69  * any => BASE64
70  */
71 static const unsigned char mbfl_base64_table[] = {
72  /* 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', */
73    0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x4b,0x4c,0x4d,
74  /* 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', */
75    0x4e,0x4f,0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5a,
76  /* 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', */
77    0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x6b,0x6c,0x6d,
78  /* 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', */
79    0x6e,0x6f,0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,
80  /* '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/', '\0' */
81    0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0x2b,0x2f,0x00
82 };
83 
mbfl_filt_conv_base64enc(int c,mbfl_convert_filter * filter)84 int mbfl_filt_conv_base64enc(int c, mbfl_convert_filter *filter)
85 {
86 	int n;
87 
88 	n = (filter->status & 0xff);
89 	if (n == 0) {
90 		filter->status++;
91 		filter->cache = (c & 0xff) << 16;
92 	} else if (n == 1) {
93 		filter->status++;
94 		filter->cache |= (c & 0xff) << 8;
95 	} else {
96 		filter->status &= ~0xff;
97 		if ((filter->status & MBFL_BASE64_STS_MIME_HEADER) == 0) {
98 			n = (filter->status & 0xff00) >> 8;
99 			if (n > 72) {
100 				CK((*filter->output_function)(0x0d, filter->data));		/* CR */
101 				CK((*filter->output_function)(0x0a, filter->data));		/* LF */
102 				filter->status &= ~0xff00;
103 			}
104 			filter->status += 0x400;
105 		}
106 		n = filter->cache | (c & 0xff);
107 		CK((*filter->output_function)(mbfl_base64_table[(n >> 18) & 0x3f], filter->data));
108 		CK((*filter->output_function)(mbfl_base64_table[(n >> 12) & 0x3f], filter->data));
109 		CK((*filter->output_function)(mbfl_base64_table[(n >> 6) & 0x3f], filter->data));
110 		CK((*filter->output_function)(mbfl_base64_table[n & 0x3f], filter->data));
111 	}
112 
113 	return c;
114 }
115 
mbfl_filt_conv_base64enc_flush(mbfl_convert_filter * filter)116 int mbfl_filt_conv_base64enc_flush(mbfl_convert_filter *filter)
117 {
118 	int status, cache, len;
119 
120 	status = filter->status & 0xff;
121 	cache = filter->cache;
122 	len = (filter->status & 0xff00) >> 8;
123 	filter->status &= ~0xffff;
124 	filter->cache = 0;
125 	/* flush fragments */
126 	if (status >= 1) {
127 		if ((filter->status & MBFL_BASE64_STS_MIME_HEADER) == 0) {
128 			if (len > 72){
129 				CK((*filter->output_function)(0x0d, filter->data));		/* CR */
130 				CK((*filter->output_function)(0x0a, filter->data));		/* LF */
131 			}
132 		}
133 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 18) & 0x3f], filter->data));
134 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 12) & 0x3f], filter->data));
135 		if (status == 1) {
136 			CK((*filter->output_function)(0x3d, filter->data));		/* '=' */
137 			CK((*filter->output_function)(0x3d, filter->data));		/* '=' */
138 		} else {
139 			CK((*filter->output_function)(mbfl_base64_table[(cache >> 6) & 0x3f], filter->data));
140 			CK((*filter->output_function)(0x3d, filter->data));		/* '=' */
141 		}
142 	}
143 	return 0;
144 }
145 
146 /*
147  * BASE64 => any
148  */
mbfl_filt_conv_base64dec(int c,mbfl_convert_filter * filter)149 int mbfl_filt_conv_base64dec(int c, mbfl_convert_filter *filter)
150 {
151 	int n;
152 
153 	if (c == 0x0d || c == 0x0a || c == 0x20 || c == 0x09 || c == 0x3d) {	/* CR or LF or SPACE or HTAB or '=' */
154 		return c;
155 	}
156 
157 	n = 0;
158 	if (c >= 0x41 && c <= 0x5a) {		/* A - Z */
159 		n = c - 65;
160 	} else if (c >= 0x61 && c <= 0x7a) {	/* a - z */
161 		n = c - 71;
162 	} else if (c >= 0x30 && c <= 0x39) {	/* 0 - 9 */
163 		n = c + 4;
164 	} else if (c == 0x2b) {			/* '+' */
165 		n = 62;
166 	} else if (c == 0x2f) {			/* '/' */
167 		n = 63;
168 	}
169 	n &= 0x3f;
170 
171 	switch (filter->status) {
172 	case 0:
173 		filter->status = 1;
174 		filter->cache = n << 18;
175 		break;
176 	case 1:
177 		filter->status = 2;
178 		filter->cache |= n << 12;
179 		break;
180 	case 2:
181 		filter->status = 3;
182 		filter->cache |= n << 6;
183 		break;
184 	default:
185 		filter->status = 0;
186 		n |= filter->cache;
187 		CK((*filter->output_function)((n >> 16) & 0xff, filter->data));
188 		CK((*filter->output_function)((n >> 8) & 0xff, filter->data));
189 		CK((*filter->output_function)(n & 0xff, filter->data));
190 		break;
191 	}
192 
193 	return c;
194 }
195 
mbfl_filt_conv_base64dec_flush(mbfl_convert_filter * filter)196 int mbfl_filt_conv_base64dec_flush(mbfl_convert_filter *filter)
197 {
198 	int status, cache;
199 
200 	status = filter->status;
201 	cache = filter->cache;
202 	filter->status = 0;
203 	filter->cache = 0;
204 	/* flush fragments */
205 	if (status >= 2) {
206 		CK((*filter->output_function)((cache >> 16) & 0xff, filter->data));
207 		if (status >= 3) {
208 			CK((*filter->output_function)((cache >> 8) & 0xff, filter->data));
209 		}
210 	}
211 	return 0;
212 }
213