xref: /PHP-5.4/ext/standard/base64.c (revision c0d060f5)
1 /*
2    +----------------------------------------------------------------------+
3    | PHP Version 5                                                        |
4    +----------------------------------------------------------------------+
5    | Copyright (c) 1997-2014 The PHP Group                                |
6    +----------------------------------------------------------------------+
7    | This source file is subject to version 3.01 of the PHP license,      |
8    | that is bundled with this package in the file LICENSE, and is        |
9    | available through the world-wide-web at the following url:           |
10    | http://www.php.net/license/3_01.txt                                  |
11    | If you did not receive a copy of the PHP license and are unable to   |
12    | obtain it through the world-wide-web, please send a note to          |
13    | license@php.net so we can mail you a copy immediately.               |
14    +----------------------------------------------------------------------+
15    | Author: Jim Winstead <jimw@php.net>                                  |
16    +----------------------------------------------------------------------+
17  */
18 /* $Id$ */
19 
20 #include <string.h>
21 
22 #include "php.h"
23 #include "base64.h"
24 
25 /* {{{ base64 tables */
26 static const char base64_table[] = {
27 	'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
28 	'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
29 	'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
30 	'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
31 	'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/', '\0'
32 };
33 
34 static const char base64_pad = '=';
35 
36 static const short base64_reverse_table[256] = {
37 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -1, -1, -2, -2, -1, -2, -2,
38 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
39 	-1, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, 62, -2, -2, -2, 63,
40 	52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -2, -2, -2, -2, -2, -2,
41 	-2,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
42 	15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -2, -2, -2, -2, -2,
43 	-2, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
44 	41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -2, -2, -2, -2, -2,
45 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
46 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
47 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
48 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
49 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
50 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
51 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
52 	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2
53 };
54 /* }}} */
55 
php_base64_encode(const unsigned char * str,int length,int * ret_length)56 PHPAPI unsigned char *php_base64_encode(const unsigned char *str, int length, int *ret_length) /* {{{ */
57 {
58 	const unsigned char *current = str;
59 	unsigned char *p;
60 	unsigned char *result;
61 
62 	if (length < 0) {
63 		if (ret_length != NULL) {
64 			*ret_length = 0;
65 		}
66 		return NULL;
67 	}
68 
69 	result = (unsigned char *) safe_emalloc((length + 2) / 3, 4 * sizeof(char), 1);
70 	p = result;
71 
72 	while (length > 2) { /* keep going until we have less than 24 bits */
73 		*p++ = base64_table[current[0] >> 2];
74 		*p++ = base64_table[((current[0] & 0x03) << 4) + (current[1] >> 4)];
75 		*p++ = base64_table[((current[1] & 0x0f) << 2) + (current[2] >> 6)];
76 		*p++ = base64_table[current[2] & 0x3f];
77 
78 		current += 3;
79 		length -= 3; /* we just handle 3 octets of data */
80 	}
81 
82 	/* now deal with the tail end of things */
83 	if (length != 0) {
84 		*p++ = base64_table[current[0] >> 2];
85 		if (length > 1) {
86 			*p++ = base64_table[((current[0] & 0x03) << 4) + (current[1] >> 4)];
87 			*p++ = base64_table[(current[1] & 0x0f) << 2];
88 			*p++ = base64_pad;
89 		} else {
90 			*p++ = base64_table[(current[0] & 0x03) << 4];
91 			*p++ = base64_pad;
92 			*p++ = base64_pad;
93 		}
94 	}
95 	if (ret_length != NULL) {
96 		*ret_length = (int)(p - result);
97 	}
98 	*p = '\0';
99 	return result;
100 }
101 /* }}} */
102 
103 /* {{{ */
104 /* generate reverse table (do not set index 0 to 64)
105 static unsigned short base64_reverse_table[256];
106 #define rt base64_reverse_table
107 void php_base64_init(void)
108 {
109 	char *s = emalloc(10240), *sp;
110 	char *chp;
111 	short idx;
112 
113 	for(ch = 0; ch < 256; ch++) {
114 		chp = strchr(base64_table, ch);
115 		if(ch && chp) {
116 			idx = chp - base64_table;
117 			if (idx >= 64) idx = -1;
118 			rt[ch] = idx;
119 		} else {
120 			rt[ch] = -1;
121 		}
122 	}
123 	sp = s;
124 	sprintf(sp, "static const short base64_reverse_table[256] = {\n");
125 	for(ch =0; ch < 256;) {
126 		sp = s+strlen(s);
127 		sprintf(sp, "\t% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,% 3d,\n", rt[ch+0], rt[ch+1], rt[ch+2], rt[ch+3], rt[ch+4], rt[ch+5], rt[ch+6], rt[ch+7], rt[ch+8], rt[ch+9], rt[ch+10], rt[ch+11], rt[ch+12], rt[ch+13], rt[ch+14], rt[ch+15]);
128 		ch += 16;
129 	}
130 	sprintf(sp, "};");
131 	php_error_docref(NULL TSRMLS_CC, E_NOTICE, "Reverse_table:\n%s", s);
132 	efree(s);
133 }
134 */
135 /* }}} */
136 
php_base64_decode(const unsigned char * str,int length,int * ret_length)137 PHPAPI unsigned char *php_base64_decode(const unsigned char *str, int length, int *ret_length) /* {{{ */
138 {
139 	return php_base64_decode_ex(str, length, ret_length, 0);
140 }
141 /* }}} */
142 
php_base64_decode_ex(const unsigned char * str,int length,int * ret_length,zend_bool strict)143 PHPAPI unsigned char *php_base64_decode_ex(const unsigned char *str, int length, int *ret_length, zend_bool strict) /* {{{ */
144 {
145 	const unsigned char *current = str;
146 	int ch, i = 0, j = 0, k;
147 	/* this sucks for threaded environments */
148 	unsigned char *result;
149 
150 	result = (unsigned char *)safe_emalloc(length, 1, 1);
151 
152 	/* run through the whole string, converting as we go */
153 	while ((ch = *current++) != '\0' && length-- > 0) {
154 		if (ch == base64_pad) {
155 			if (*current != '=' && ((i % 4) == 1 || (strict && length > 0))) {
156 				if ((i % 4) != 1) {
157 					while (isspace(*(++current))) {
158 						continue;
159 					}
160 					if (*current == '\0') {
161 						continue;
162 					}
163 				}
164 				efree(result);
165 				return NULL;
166 			}
167 			continue;
168 		}
169 
170 		ch = base64_reverse_table[ch];
171 		if ((!strict && ch < 0) || ch == -1) { /* a space or some other separator character, we simply skip over */
172 			continue;
173 		} else if (ch == -2) {
174 			efree(result);
175 			return NULL;
176 		}
177 
178 		switch(i % 4) {
179 		case 0:
180 			result[j] = ch << 2;
181 			break;
182 		case 1:
183 			result[j++] |= ch >> 4;
184 			result[j] = (ch & 0x0f) << 4;
185 			break;
186 		case 2:
187 			result[j++] |= ch >>2;
188 			result[j] = (ch & 0x03) << 6;
189 			break;
190 		case 3:
191 			result[j++] |= ch;
192 			break;
193 		}
194 		i++;
195 	}
196 
197 	k = j;
198 	/* mop things up if we ended on a boundary */
199 	if (ch == base64_pad) {
200 		switch(i % 4) {
201 		case 1:
202 			efree(result);
203 			return NULL;
204 		case 2:
205 			k++;
206 		case 3:
207 			result[k] = 0;
208 		}
209 	}
210 	if(ret_length) {
211 		*ret_length = j;
212 	}
213 	result[j] = '\0';
214 	return result;
215 }
216 /* }}} */
217 
218 /* {{{ proto string base64_encode(string str)
219    Encodes string using MIME base64 algorithm */
PHP_FUNCTION(base64_encode)220 PHP_FUNCTION(base64_encode)
221 {
222 	char *str;
223 	unsigned char *result;
224 	int str_len, ret_length;
225 
226 	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &str, &str_len) == FAILURE) {
227 		return;
228 	}
229 	result = php_base64_encode((unsigned char*)str, str_len, &ret_length);
230 	if (result != NULL) {
231 		RETVAL_STRINGL((char*)result, ret_length, 0);
232 	} else {
233 		RETURN_FALSE;
234 	}
235 }
236 /* }}} */
237 
238 /* {{{ proto string base64_decode(string str[, bool strict])
239    Decodes string using MIME base64 algorithm */
PHP_FUNCTION(base64_decode)240 PHP_FUNCTION(base64_decode)
241 {
242 	char *str;
243 	unsigned char *result;
244 	zend_bool strict = 0;
245 	int str_len, ret_length;
246 
247 	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|b", &str, &str_len, &strict) == FAILURE) {
248 		return;
249 	}
250 	result = php_base64_decode_ex((unsigned char*)str, str_len, &ret_length, strict);
251 	if (result != NULL) {
252 		RETVAL_STRINGL((char*)result, ret_length, 0);
253 	} else {
254 		RETURN_FALSE;
255 	}
256 }
257 /* }}} */
258 
259 /*
260  * Local variables:
261  * tab-width: 4
262  * c-basic-offset: 4
263  * End:
264  * vim600: sw=4 ts=4 fdm=marker
265  * vim<600: sw=4 ts=4
266  */
267