1 /*
2
3 Encode or decode file as MIME base64 (RFC 1341)
4
5 by John Walker
6 http://www.fourmilab.ch/
7
8 This program is in the public domain.
9
10 */
11 #include <stdio.h>
12
13 /* ENCODE -- Encode binary file into base64. */
14 #include <stdlib.h>
15 #include <ctype.h>
16 #include <php.h>
17
18 #include "base64.h"
19
20 static unsigned char dtable[512];
21
buffer_new(struct buffer_st * b)22 void buffer_new(struct buffer_st *b)
23 {
24 b->length = 512;
25 b->data = emalloc(sizeof(char)*(b->length));
26 b->data[0] = 0;
27 b->ptr = b->data;
28 b->offset = 0;
29 }
30
buffer_add(struct buffer_st * b,char c)31 void buffer_add(struct buffer_st *b, char c)
32 {
33 if ((INT_MAX - b->length) <= 512) {
34 return;
35 }
36 *(b->ptr++) = c;
37 b->offset++;
38 if (b->offset == b->length) {
39 b->length += 512;
40 b->data = erealloc(b->data, b->length);
41 b->ptr = b->data + b->offset;
42 }
43 }
44
buffer_delete(struct buffer_st * b)45 void buffer_delete(struct buffer_st *b)
46 {
47 efree(b->data);
48 b->length = 0;
49 b->offset = 0;
50 b->ptr = NULL;
51 b->data = NULL;
52 }
53
base64_encode_xmlrpc(struct buffer_st * b,const char * source,int length)54 void base64_encode_xmlrpc(struct buffer_st *b, const char *source, int length)
55 {
56 int i, hiteof = 0;
57 int offset = 0;
58
59 buffer_new(b);
60
61 /* Fill dtable with character encodings. */
62
63 for (i = 0; i < 26; i++) {
64 dtable[i] = 'A' + i;
65 dtable[26 + i] = 'a' + i;
66 }
67 for (i = 0; i < 10; i++) {
68 dtable[52 + i] = '0' + i;
69 }
70 dtable[62] = '+';
71 dtable[63] = '/';
72
73 while (!hiteof) {
74 unsigned char igroup[3], ogroup[4];
75 int c, n;
76
77 igroup[0] = igroup[1] = igroup[2] = 0;
78 for (n = 0; n < 3; n++) {
79 c = *(source++);
80 offset++;
81 if (offset > length || offset <= 0) {
82 hiteof = 1;
83 break;
84 }
85 igroup[n] = (unsigned char) c;
86 }
87 if (n > 0) {
88 ogroup[0] = dtable[igroup[0] >> 2];
89 ogroup[1] = dtable[((igroup[0] & 3) << 4) | (igroup[1] >> 4)];
90 ogroup[2] = dtable[((igroup[1] & 0xF) << 2) | (igroup[2] >> 6)];
91 ogroup[3] = dtable[igroup[2] & 0x3F];
92
93 /* Replace characters in output stream with "=" pad
94 characters if fewer than three characters were
95 read from the end of the input stream. */
96
97 if (n < 3) {
98 ogroup[3] = '=';
99 if (n < 2) {
100 ogroup[2] = '=';
101 }
102 }
103 for (i = 0; i < 4; i++) {
104 buffer_add(b, ogroup[i]);
105 if (!(b->offset % 72)) {
106 /* buffer_add(b, '\r'); */
107 buffer_add(b, '\n');
108 }
109 }
110 }
111 }
112 /* buffer_add(b, '\r'); */
113 buffer_add(b, '\n');
114 }
115
base64_decode_xmlrpc(struct buffer_st * bfr,const char * source,int length)116 void base64_decode_xmlrpc(struct buffer_st *bfr, const char *source, int length)
117 {
118 int i;
119 int offset = 0;
120 int endoffile;
121 int count;
122
123 buffer_new(bfr);
124
125 for (i = 0; i < 255; i++) {
126 dtable[i] = 0x80;
127 }
128 for (i = 'A'; i <= 'Z'; i++) {
129 dtable[i] = 0 + (i - 'A');
130 }
131 for (i = 'a'; i <= 'z'; i++) {
132 dtable[i] = 26 + (i - 'a');
133 }
134 for (i = '0'; i <= '9'; i++) {
135 dtable[i] = 52 + (i - '0');
136 }
137 dtable['+'] = 62;
138 dtable['/'] = 63;
139 dtable['='] = 0;
140
141 endoffile = 0;
142
143 /*CONSTANTCONDITION*/
144 while (1) {
145 unsigned char a[4], b[4], o[3];
146
147 for (i = 0; i < 4; i++) {
148 int c;
149 while (1) {
150 c = *(source++);
151 offset++;
152 if (offset > length) endoffile = 1;
153 if (isspace(c) || c == '\n' || c == '\r') continue;
154 break;
155 }
156
157 if (endoffile) {
158 /*
159 if (i > 0) {
160 fprintf(stderr, "Input file incomplete.\n");
161 exit(1);
162 }
163 */
164 return;
165 }
166
167 if (dtable[(unsigned char)c] & 0x80) {
168 /*
169 fprintf(stderr, "Offset %i length %i\n", offset, length);
170 fprintf(stderr, "character '%c:%x:%c' in input file.\n", c, c, dtable[c]);
171 exit(1);
172 */
173 i--;
174 continue;
175 }
176 a[i] = (unsigned char) c;
177 b[i] = (unsigned char) dtable[c];
178 }
179 o[0] = (b[0] << 2) | (b[1] >> 4);
180 o[1] = (b[1] << 4) | (b[2] >> 2);
181 o[2] = (b[2] << 6) | b[3];
182 i = a[2] == '=' ? 1 : (a[3] == '=' ? 2 : 3);
183 count = 0;
184 while (count < i) {
185 buffer_add(bfr, o[count++]);
186 }
187 if (i < 3) {
188 return;
189 }
190 }
191 }
192