apply the big auth patch

1 files changed, 90 insertions, 0 deletions

diff --git a/base64.c b/base64.c
new file mode 100644
index 0000000..fbce145
--- /dev/null
+++ b/base64.c
@@ -0,0 +1,90 @@
+#include "base64.h"
+#include "stralloc.h"
+#include "substdio.h"
+#include "str.h"
+
+static char *b64alpha =
+  "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+#define B64PAD '='
+
+/* returns 0 ok, 1 illegal, -1 problem */
+
+int b64decode(in,l,out)
+const unsigned char *in;
+int l;
+stralloc *out; /* not null terminated */
+{
+  int i, j;
+  unsigned char a[4];
+  unsigned char b[3];
+  char *s;
+
+  if (l == 0)
+  {
+    if (!stralloc_copys(out,"")) return -1;
+    return 0;
+  }
+
+  if (!stralloc_ready(out,l + 2)) return -1; /* XXX generous */
+  s = out->s;
+
+  for (i = 0;i < l;i += 4) {
+    for (j = 0;j < 4;j++)
+      if ((i + j) < l && in[i + j] != B64PAD)
+      {
+        a[j] = str_chr(b64alpha,in[i + j]);
+        if (a[j] > 63) return 1;
+      }
+      else a[j] = 0;
+
+    b[0] = (a[0] << 2) | (a[1] >> 4);
+    b[1] = (a[1] << 4) | (a[2] >> 2);
+    b[2] = (a[2] << 6) | (a[3]);
+
+    *s++ = b[0];
+
+    if (in[i + 1] == B64PAD) break;
+    *s++ = b[1];
+
+    if (in[i + 2] == B64PAD) break;
+    *s++ = b[2];
+  }
+  out->len = s - out->s;
+  while (out->len && !out->s[out->len - 1]) --out->len; /* XXX avoid? */
+  return 0;
+}
+
+int b64encode(in,out)
+stralloc *in;
+stralloc *out; /* not null terminated */
+{
+  unsigned char a, b, c;
+  int i;
+  char *s;
+
+  if (in->len == 0)
+  {
+    if (!stralloc_copys(out,"")) return -1;
+    return 0;
+  }
+
+  if (!stralloc_ready(out,in->len / 3 * 4 + 4)) return -1;
+  s = out->s;
+
+  for (i = 0;i < in->len;i += 3) {
+    a = in->s[i];
+    b = i + 1 < in->len ? in->s[i + 1] : 0;
+    c = i + 2 < in->len ? in->s[i + 2] : 0;
+
+    *s++ = b64alpha[a >> 2];
+    *s++ = b64alpha[((a & 3 ) << 4) | (b >> 4)];
+
+    if (i + 1 >= in->len) *s++ = B64PAD;
+    else *s++ = b64alpha[((b & 15) << 2) | (c >> 6)];
+
+    if (i + 2 >= in->len) *s++ = B64PAD;
+    else *s++ = b64alpha[c & 63];
+  }
+  out->len = s - out->s;
+  return 0;
+}