1 static const char rcsid[] = "#(@) $Id$";
2
3 /*
4
5 Encode or decode file as MIME base64 (RFC 1341)
6
7 by John Walker
8 http://www.fourmilab.ch/
9
10 This program is in the public domain.
11
12 */
13 #include <stdio.h>
14
15 /* ENCODE -- Encode binary file into base64. */
16 #include <stdlib.h>
17 #include <ctype.h>
18 #include <limits.h>
19
20 #include "base64.h"
21
22 static unsigned char dtable[512];
23
buffer_new(struct buffer_st * b)24 void buffer_new(struct buffer_st *b)
25 {
26 b->length = 512;
27 b->data = malloc(sizeof(char)*(b->length));
28 b->data[0] = 0;
29 b->ptr = b->data;
30 b->offset = 0;
31 }
32
buffer_add(struct buffer_st * b,char c)33 void buffer_add(struct buffer_st *b, char c)
34 {
35 if ((INT_MAX - b->length) <= 512) {
36 return;
37 }
38 *(b->ptr++) = c;
39 b->offset++;
40 if (b->offset == b->length) {
41 b->length += 512;
42 b->data = realloc(b->data, b->length);
43 b->ptr = b->data + b->offset;
44 }
45 }
46
buffer_delete(struct buffer_st * b)47 void buffer_delete(struct buffer_st *b)
48 {
49 free(b->data);
50 b->length = 0;
51 b->offset = 0;
52 b->ptr = NULL;
53 b->data = NULL;
54 }
55
base64_encode_xmlrpc(struct buffer_st * b,const char * source,int length)56 void base64_encode_xmlrpc(struct buffer_st *b, const char *source, int length)
57 {
58 int i, hiteof = 0;
59 int offset = 0;
60 int olen;
61
62 olen = 0;
63
64 buffer_new(b);
65
66 /* Fill dtable with character encodings. */
67
68 for (i = 0; i < 26; i++) {
69 dtable[i] = 'A' + i;
70 dtable[26 + i] = 'a' + i;
71 }
72 for (i = 0; i < 10; i++) {
73 dtable[52 + i] = '0' + i;
74 }
75 dtable[62] = '+';
76 dtable[63] = '/';
77
78 while (!hiteof) {
79 unsigned char igroup[3], ogroup[4];
80 int c, n;
81
82 igroup[0] = igroup[1] = igroup[2] = 0;
83 for (n = 0; n < 3; n++) {
84 c = *(source++);
85 offset++;
86 if (offset > length || offset <= 0) {
87 hiteof = 1;
88 break;
89 }
90 igroup[n] = (unsigned char) c;
91 }
92 if (n > 0) {
93 ogroup[0] = dtable[igroup[0] >> 2];
94 ogroup[1] = dtable[((igroup[0] & 3) << 4) | (igroup[1] >> 4)];
95 ogroup[2] = dtable[((igroup[1] & 0xF) << 2) | (igroup[2] >> 6)];
96 ogroup[3] = dtable[igroup[2] & 0x3F];
97
98 /* Replace characters in output stream with "=" pad
99 characters if fewer than three characters were
100 read from the end of the input stream. */
101
102 if (n < 3) {
103 ogroup[3] = '=';
104 if (n < 2) {
105 ogroup[2] = '=';
106 }
107 }
108 for (i = 0; i < 4; i++) {
109 buffer_add(b, ogroup[i]);
110 if (!(b->offset % 72)) {
111 /* buffer_add(b, '\r'); */
112 buffer_add(b, '\n');
113 }
114 }
115 }
116 }
117 /* buffer_add(b, '\r'); */
118 buffer_add(b, '\n');
119 }
120
base64_decode_xmlrpc(struct buffer_st * bfr,const char * source,int length)121 void base64_decode_xmlrpc(struct buffer_st *bfr, const char *source, int length)
122 {
123 int i;
124 int offset = 0;
125 int endoffile;
126 int count;
127
128 buffer_new(bfr);
129
130 for (i = 0; i < 255; i++) {
131 dtable[i] = 0x80;
132 }
133 for (i = 'A'; i <= 'Z'; i++) {
134 dtable[i] = 0 + (i - 'A');
135 }
136 for (i = 'a'; i <= 'z'; i++) {
137 dtable[i] = 26 + (i - 'a');
138 }
139 for (i = '0'; i <= '9'; i++) {
140 dtable[i] = 52 + (i - '0');
141 }
142 dtable['+'] = 62;
143 dtable['/'] = 63;
144 dtable['='] = 0;
145
146 endoffile = 0;
147
148 /*CONSTANTCONDITION*/
149 while (1) {
150 unsigned char a[4], b[4], o[3];
151
152 for (i = 0; i < 4; i++) {
153 int c;
154 while (1) {
155 c = *(source++);
156 offset++;
157 if (offset > length) endoffile = 1;
158 if (isspace(c) || c == '\n' || c == '\r') continue;
159 break;
160 }
161
162 if (endoffile) {
163 /*
164 if (i > 0) {
165 fprintf(stderr, "Input file incomplete.\n");
166 exit(1);
167 }
168 */
169 return;
170 }
171
172 if (dtable[c] & 0x80) {
173 /*
174 fprintf(stderr, "Offset %i length %i\n", offset, length);
175 fprintf(stderr, "character '%c:%x:%c' in input file.\n", c, c, dtable[c]);
176 exit(1);
177 */
178 i--;
179 continue;
180 }
181 a[i] = (unsigned char) c;
182 b[i] = (unsigned char) dtable[c];
183 }
184 o[0] = (b[0] << 2) | (b[1] >> 4);
185 o[1] = (b[1] << 4) | (b[2] >> 2);
186 o[2] = (b[2] << 6) | b[3];
187 i = a[2] == '=' ? 1 : (a[3] == '=' ? 2 : 3);
188 count = 0;
189 while (count < i) {
190 buffer_add(bfr, o[count++]);
191 }
192 if (i < 3) {
193 return;
194 }
195 }
196 }
197
