1 files changed, 93 insertions, 0 deletions
diff --git a/lib/Base64.cc b/lib/Base64.cc
new file mode 100644
index 0000000..062dae4
--- /dev/null
+++ b/lib/Base64.cc
@@ -0,0 +1,93 @@
+#include <Base64.h>
+
+static char cb64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+String Base64::encode_block(unsigned char in_tab[3], int len) {
+    char r[5];
+    
+    r[0] = cb64[in_tab[0] >> 2];
+    r[1] = cb64[((in_tab[0] & 3) << 4) | ((in_tab[1] & 240) >> 4)];
+    r[2] = len > 1 ? cb64[((in_tab[1] & 15) << 2) | ((in_tab[2] & 192) >> 6)] : '=';
+    r[3] = len > 2 ? cb64[in_tab[2] & 63] : '=';
+    r[4] = 0;
+    
+    return r;
+}
+
+String Base64::encode(char * data, int stream_size) {
+    String encoded = "";
+    unsigned char in_tab[3];
+    int len, i, s_pos;
+
+    s_pos = 0;
+
+    while (stream_size > 0) {
+        in_tab[0] = 0;
+        in_tab[1] = 0;
+        in_tab[2] = 0;
+
+        len = stream_size >= 3 ? 3 : stream_size;
+
+        for (i = 0; i < len; i++) {
+            in_tab[i] = data[s_pos + i];
+        }
+
+        encoded += encode_block(in_tab, len);
+
+        s_pos += 3;
+        stream_size -= 3;
+    }
+
+    return encoded;
+}
+
+int Base64::stri(char x) {
+    char * p = strchr(cb64, x);
+    return ((x == '=') || (p == 0)) ? -1 : (p - cb64);
+}
+
+int Base64::decode_block(char s1, char s2, char s3, char s4, unsigned char * out_tab) {
+    int len, sb1, sb2, sb3, sb4;
+
+    len = s3 == '=' ? 1 : s4 == '=' ? 2 : 3;
+    s3 = (s3 == '=') || (s3 == 0) ? 'A' : s3;
+    s4 = (s4 == '=') || (s4 == 0) ? 'A' : s4;
+    
+    sb1 = stri(s1);
+    sb2 = stri(s2);
+    sb3 = stri(s3);
+    sb4 = stri(s4);
+    
+    out_tab[0] = (sb1 << 2) | (sb2 >> 4);
+    out_tab[1] = ((sb2 << 4) & 255) | (sb3 >> 2);
+    out_tab[2] = ((sb3 << 6) & 240) | sb4;
+    
+    return len;
+}
+
+unsigned char * Base64::decode(const String & str_in, int * len_out) {
+    int s_len = str_in.strlen() / 4, len = 0, i, j, t_len;
+    char s1, s2, s3, s4;
+    unsigned char t_out[2];
+    unsigned char * out = (unsigned char *) malloc(s_len * 3);
+    
+    for (i = 0; i < s_len; i++) {
+        s1 = str_in[i * 4 + 0];
+        s2 = str_in[i * 4 + 1];
+        s3 = str_in[i * 4 + 2];
+        s4 = str_in[i * 4 + 3];
+        t_len = decode_block(s1, s2, s3, s4, t_out);
+
+        for (j = 0; j < t_len; j++) {
+            out[i * 3 + j] = t_out[j];
+        }
+
+        len += t_len;
+    }
+    
+    if (len_out) {
+        *len_out = len;
+    }
+
+    return out;
+}