ReactOS  0.4.14-dev-55-g2da92ac
base64_codec.c
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1 /*
2  * base64 encoder/decoder
3  *
4  * Copyright 2005 by Kai Blin
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library 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 GNU
14  * 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 this library; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
19  */
20 
21 #include "precomp.h"
22 
23 #include <wine/debug.h>
25 
26 static const char b64[] =
27 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
28 
29 SECURITY_STATUS encodeBase64(PBYTE in_buf, int in_len, char* out_buf,
30  int max_len, int *out_len)
31 {
32  int div, i;
33  PBYTE d = in_buf;
34  int bytes = (in_len*8 + 5)/6, pad_bytes = (bytes % 4) ? 4 - (bytes % 4) : 0;
35 
36  TRACE("bytes is %d, pad bytes is %d\n", bytes, pad_bytes);
37  *out_len = bytes + pad_bytes;
38 
39  if(bytes + pad_bytes + 1 > max_len)
41 
42  /* Three bytes of input give 4 chars of output */
43  div = in_len / 3;
44 
45  i = 0;
46  while(div > 0)
47  {
48  /* first char is the first 6 bits of the first byte*/
49  out_buf[i + 0] = b64[ ( d[0] >> 2) & 0x3f ];
50  /* second char is the last 2 bits of the first byte and the first 4
51  * bits of the second byte */
52  out_buf[i + 1] = b64[ ((d[0] << 4) & 0x30) | (d[1] >> 4 & 0x0f)];
53  /* third char is the last 4 bits of the second byte and the first 2
54  * bits of the third byte */
55  out_buf[i + 2] = b64[ ((d[1] << 2) & 0x3c) | (d[2] >> 6 & 0x03)];
56  /* fourth char is the remaining 6 bits of the third byte */
57  out_buf[i + 3] = b64[ d[2] & 0x3f];
58  i += 4;
59  d += 3;
60  div--;
61  }
62 
63  switch(pad_bytes)
64  {
65  case 1:
66  /* first char is the first 6 bits of the first byte*/
67  out_buf[i + 0] = b64[ ( d[0] >> 2) & 0x3f ];
68  /* second char is the last 2 bits of the first byte and the first 4
69  * bits of the second byte */
70  out_buf[i + 1] = b64[ ((d[0] << 4) & 0x30) | (d[1] >> 4 & 0x0f)];
71  /* third char is the last 4 bits of the second byte padded with
72  * two zeroes */
73  out_buf[i + 2] = b64[ ((d[1] << 2) & 0x3c) ];
74  /* fourth char is a = to indicate one byte of padding */
75  out_buf[i + 3] = '=';
76  out_buf[i + 4] = 0;
77  break;
78  case 2:
79  /* first char is the first 6 bits of the first byte*/
80  out_buf[i + 0] = b64[ ( d[0] >> 2) & 0x3f ];
81  /* second char is the last 2 bits of the first byte padded with
82  * four zeroes*/
83  out_buf[i + 1] = b64[ ((d[0] << 4) & 0x30)];
84  /* third char is = to indicate padding */
85  out_buf[i + 2] = '=';
86  /* fourth char is = to indicate padding */
87  out_buf[i + 3] = '=';
88  out_buf[i + 4] = 0;
89  break;
90  default:
91  out_buf[i] = 0;
92  }
93 
94  return SEC_E_OK;
95 }
96 
97 static inline BYTE decode(char c)
98 {
99  if( c >= 'A' && c <= 'Z')
100  return c - 'A';
101  if( c >= 'a' && c <= 'z')
102  return c - 'a' + 26;
103  if( c >= '0' && c <= '9')
104  return c - '0' + 52;
105  if( c == '+')
106  return 62;
107  if( c == '/')
108  return 63;
109  else
110  return 64;
111 }
112 
113 SECURITY_STATUS decodeBase64(char *in_buf, int in_len, PBYTE out_buf,
114  int max_len, int *out_len)
115 {
116  int len = in_len, i;
117  char *d = in_buf;
118  int ip0, ip1, ip2, ip3;
119 
120  TRACE("in_len: %d\n", in_len);
121 
122  if((in_len % 4) != 0)
123  return SEC_E_INVALID_TOKEN;
124 
125  if(in_len > max_len)
126  return SEC_E_BUFFER_TOO_SMALL;
127 
128  i = 0;
129  while(len > 4)
130  {
131  if((ip0 = decode(d[0])) > 63)
132  return SEC_E_INVALID_TOKEN;
133  if((ip1 = decode(d[1])) > 63)
134  return SEC_E_INVALID_TOKEN;
135  if((ip2 = decode(d[2])) > 63)
136  return SEC_E_INVALID_TOKEN;
137  if((ip3 = decode(d[3])) > 63)
138  return SEC_E_INVALID_TOKEN;
139 
140  out_buf[i + 0] = (ip0 << 2) | (ip1 >> 4);
141  out_buf[i + 1] = (ip1 << 4) | (ip2 >> 2);
142  out_buf[i + 2] = (ip2 << 6) | ip3;
143  len -= 4;
144  i += 3;
145  d += 4;
146  }
147 
148  if(d[2] == '=')
149  {
150  if((ip0 = decode(d[0])) > 63)
151  return SEC_E_INVALID_TOKEN;
152  if((ip1 = decode(d[1])) > 63)
153  return SEC_E_INVALID_TOKEN;
154 
155  out_buf[i] = (ip0 << 2) | (ip1 >> 4);
156  i++;
157  }
158  else if(d[3] == '=')
159  {
160  if((ip0 = decode(d[0])) > 63)
161  return SEC_E_INVALID_TOKEN;
162  if((ip1 = decode(d[1])) > 63)
163  return SEC_E_INVALID_TOKEN;
164  if((ip2 = decode(d[2])) > 63)
165  return SEC_E_INVALID_TOKEN;
166 
167  out_buf[i + 0] = (ip0 << 2) | (ip1 >> 4);
168  out_buf[i + 1] = (ip1 << 4) | (ip2 >> 2);
169  i += 2;
170  }
171  else
172  {
173  if((ip0 = decode(d[0])) > 63)
174  return SEC_E_INVALID_TOKEN;
175  if((ip1 = decode(d[1])) > 63)
176  return SEC_E_INVALID_TOKEN;
177  if((ip2 = decode(d[2])) > 63)
178  return SEC_E_INVALID_TOKEN;
179  if((ip3 = decode(d[3])) > 63)
180  return SEC_E_INVALID_TOKEN;
181 
182 
183  out_buf[i + 0] = (ip0 << 2) | (ip1 >> 4);
184  out_buf[i + 1] = (ip1 << 4) | (ip2 >> 2);
185  out_buf[i + 2] = (ip2 << 6) | ip3;
186  i += 3;
187  }
188  *out_len = i;
189  return SEC_E_OK;
190 }
SECURITY_STATUS encodeBase64(PBYTE in_buf, int in_len, char *out_buf, int max_len, int *out_len)
Definition: base64_codec.c:29
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
static unsigned char bytes[4]
Definition: adnsresfilter.c:74
static const char b64[]
Definition: base64_codec.c:26
SECURITY_STATUS decodeBase64(char *in_buf, int in_len, PBYTE out_buf, int max_len, int *out_len)
Definition: base64_codec.c:113
LONG SECURITY_STATUS
Definition: sspi.h:34
#define TRACE(s)
Definition: solgame.cpp:4
#define d
Definition: ke_i.h:81
_STLP_VENDOR_CSTD::ldiv_t div(long __x, long __y)
Definition: _cstdlib.h:137
const GLubyte * c
Definition: glext.h:8905
WINE_DEFAULT_DEBUG_CHANNEL(ntlm)
#define SEC_E_INVALID_TOKEN
Definition: winerror.h:2917
GLenum GLsizei len
Definition: glext.h:6722
unsigned char BYTE
Definition: mem.h:68
#define SEC_E_OK
Definition: winerror.h:2356
static BYTE decode(char c)
Definition: base64_codec.c:97
#define SEC_E_BUFFER_TOO_SMALL
Definition: winerror.h:2937
BYTE * PBYTE
Definition: pedump.c:66