1 files changed, 127 insertions, 0 deletions

diff --git a/src/base64.c b/src/base64.c
new file mode 100644
index 0000000..066494e
--- /dev/null
+++ b/src/base64.c
@@ -0,0 +1,127 @@
+/*
+ * base64.c
+ * base64 encode/decode implementation
+ *
+ * Copyright (c) 2011 Nikias Bassen, All Rights Reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#include <string.h>
+#include "base64.h"
+
+static const char base64_str[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+static const char base64_pad = '=';
+
+static const int8_t base64_table[256] = {
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
+        52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
+        -1,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
+        15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
+        -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+        41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
+};
+
+char *base64encode(const unsigned char *buf, size_t *size)
+{
+        if (!buf || !size || !(*size > 0)) return NULL;
+        int outlen = (*size / 3) * 4;
+        char *outbuf = (char*)malloc(outlen+5); // 4 spare bytes + 1 for '\0'
+        size_t n = 0;
+        size_t m = 0;
+        unsigned char input[3];
+        unsigned int output[4];
+        while (n < *size) {
+                input[0] = buf[n++];
+                input[1] = (n < *size) ? buf[n++] : 0;
+                input[2] = (n < *size) ? buf[n++] : 0;
+                output[0] = input[0] >> 2;
+                output[1] = ((input[0] & 3) << 4) + (input[1] >> 4);
+                output[2] = ((input[1] & 15) << 2) + (input[2] >> 6);
+                output[3] = input[2] & 63;
+                outbuf[m++] = base64_str[(int)output[0]];
+                outbuf[m++] = base64_str[(int)output[1]];
+                outbuf[m++] = base64_str[(int)output[2]];
+                outbuf[m++] = base64_str[(int)output[3]];
+        }
+        while ((m % 4) != 0) {
+                outbuf[m++] = base64_pad;
+        }
+        outbuf[m] = 0; // 0-termination!
+        *size = m;
+        return outbuf;
+}
+
+static int base64decode_block(unsigned char *target, const char *data, size_t data_size)
+{
+        int w1,w2,w3,w4;
+        int n,i;
+
+        if (!data || (data_size <= 0)) {
+                return 0;
+        }
+
+        n = 0;
+        i = 0;
+        while (n < data_size-3) {
+                w1 = base64_table[(int)data[n]];
+                w2 = base64_table[(int)data[n+1]];
+                w3 = base64_table[(int)data[n+2]];
+                w4 = base64_table[(int)data[n+3]];
+
+                if (w2 >= 0) {
+                        target[i++] = (char)((w1*4 + (w2 >> 4)) & 255);
+                }
+                if (w3 >= 0) {
+                        target[i++] = (char)((w2*16 + (w3 >> 2)) & 255);
+                }
+                if (w4 >= 0) {
+                        target[i++] = (char)((w3*64 + w4) & 255);
+                }
+                n+=4;
+        }
+        return i;
+}
+
+unsigned char *base64decode(const char *buf, size_t *size)
+{
+        if (!buf) return;
+        size_t len = strlen(buf);
+        if (len <= 0) return;
+        unsigned char *outbuf = (unsigned char*)malloc((len/4)*3+3);
+
+        unsigned char *line;
+        int p = 0;
+
+        line = (unsigned char*)strtok((char*)buf, "\r\n\t ");
+        while (line) {
+                p+=base64decode_block(outbuf+p, line, strlen((char*)line));
+
+                // get next line of base64 encoded block
+                line = (unsigned char*)strtok(NULL, "\r\n\t ");
+        }
+        outbuf[p] = 0;
+        *size = p;
+        return outbuf;
+}