diff --git a/base64-decode.c b/base64-decode.c
new file mode 100644
index 0000000000000000000000000000000000000000..e1e614de1ef7257765fafaf8ee085679cf55ce25
--- /dev/null
+++ b/base64-decode.c
@@ -0,0 +1,135 @@
+/* base64-encode.c
+ *
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2002 Niels Möller
+ *
+ * The nettle 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.
+ *
+ * The nettle 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 the nettle library; see the file COPYING.LIB. If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#include "base64.h"
+
+#include <assert.h>
+#include <stdlib.h>
+
+#define TABLE_INVALID -1
+#define TABLE_SPACE -2
+#define TABLE_END -3
+
+static const signed char
+decode_table[0x100] =
+{
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -2, -2, -1, -1, -2, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -2, -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, -3, -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,
+};
+
+void
+base64_decode_init(struct base64_decode_ctx *ctx)
+{
+ ctx->word = ctx->bits = 0;
+ ctx->status = BASE64_DECODE_OK;
+}
+
+unsigned
+base64_decode_update(struct base64_decode_ctx *ctx,
+ uint8_t *dst,
+ unsigned length,
+ const uint8_t *src)
+{
+ unsigned done = 0;
+ unsigned i;
+
+ if (ctx->status == BASE64_DECODE_ERROR)
+ return 0;
+
+ for (i = 0; i<length; i++)
+ {
+ int data = decode_table[src[i]];
+
+ switch(data)
+ {
+ default:
+ assert(data >= 0 && data < 0x40);
+
+ if (ctx->status != BASE64_DECODE_OK)
+ goto invalid;
+
+ ctx->word = ctx->word << 6 | data;
+ ctx->bits += 6;
+
+ if (ctx->bits >= 8)
+ {
+ ctx->bits -= 8;
+ dst[done++] = ctx->word >> ctx->bits;
+ }
+ break;
+
+ case TABLE_INVALID:
+ invalid:
+ ctx->status = BASE64_DECODE_ERROR;
+ return done;
+
+ case TABLE_SPACE:
+ /* Ignore */
+ break;
+
+ case TABLE_END:
+ if (!ctx->bits)
+ goto invalid;
+ if (ctx->word & ( (1<<ctx->bits) - 1))
+ /* We shouldn't have any leftover bits */
+ goto invalid;
+
+ ctx->status = BASE64_DECODE_END;
+ ctx->bits -= 2;
+ break;
+ }
+ }
+
+ assert(done <= BASE64_DECODE_LENGTH(length));
+
+ return done;
+}
+
+int
+base64_decode_status(struct base64_decode_ctx *ctx)
+{
+ switch (ctx->status)
+ {
+ case BASE64_DECODE_END:
+ case BASE64_DECODE_OK:
+ return ctx->bits == 0;
+ case BASE64_DECODE_ERROR:
+ return 0;
+ }
+ abort();
+}
diff --git a/base64-encode.c b/base64-encode.c
new file mode 100644
index 0000000000000000000000000000000000000000..13b625268e5273171d3b854f771b5f7391cd05b1
--- /dev/null
+++ b/base64-encode.c
@@ -0,0 +1,226 @@
+/* base64-encode.c
+ *
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2002 Niels Möller
+ *
+ * The nettle 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.
+ *
+ * The nettle 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 the nettle library; see the file COPYING.LIB. If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#include "base64.h"
+
+#include <assert.h>
+#include <stdlib.h>
+
+
+static const uint8_t encode_table[64] =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+/";
+
+#define ENCODE(x) (encode_table[0x3F & (x)])
+
+void
+base64_encode_raw(uint8_t *dst, unsigned length, const uint8_t *src)
+{
+ const uint8_t *in = src + length;;
+ uint8_t *out = dst + BASE64_ENCODE_RAW_LENGTH(length);
+
+ unsigned left_over = length % 3;
+
+ if (left_over)
+ {
+ in -= left_over;
+ *--out = '=';
+ switch(left_over)
+ {
+ case 1:
+ *--out = '=';
+ *--out = ENCODE(in[0] << 4);
+ break;
+
+ case 2:
+ *--out = ENCODE( in[1] << 2);
+ *--out = ENCODE((in[0] << 4) | (in[1] >> 4));
+ break;
+
+ default:
+ abort();
+ }
+ *--out = ENCODE(in[0] >> 2);
+ }
+
+ while (in > src)
+ {
+ in -= 3;
+ *--out = ENCODE( in[2]);
+ *--out = ENCODE((in[1] << 2) | (in[2] >> 6));
+ *--out = ENCODE((in[0] << 4) | (in[1] >> 4));
+ *--out = ENCODE( in[0] >> 2);
+ }
+ assert(in == src);
+ assert(out == dst);
+}
+
+#if 0
+unsigned
+base64_encode(uint8_t *dst,
+ unsigned src_length,
+ const uint8_t *src)
+{
+ unsigned dst_length = BASE64_ENCODE_RAW_LENGTH(src_length);
+ unsigned n = src_length / 3;
+ unsigned left_over = src_length % 3;
+ unsigned done = 0;
+
+ if (left_over)
+ {
+ const uint8_t *in = src + n * 3;
+ uint8_t *out = dst + dst_length;
+
+ switch(left_over)
+ {
+ case 1:
+ *--out = '=';
+ *--out = ENCODE(in[0] << 4);
+ break;
+
+ case 2:
+ *--out = ENCODE( in[1] << 2);
+ *--out = ENCODE((in[0] << 4) | (in[1] >> 4));
+ break;
+
+ default:
+ abort();
+ }
+ *--out = ENCODE(in[0] >> 2);
+
+ done = 4;
+ }
+ base64_encode_raw(n, dst, src);
+ done += n * 4;
+
+ assert(done == dst_length);
+
+ return done;
+}
+#endif
+
+void
+base64_encode_group(uint8_t *dst, uint32_t group)
+{
+ *dst++ = ENCODE(group >> 18);
+ *dst++ = ENCODE(group >> 12);
+ *dst++ = ENCODE(group >> 6);
+ *dst++ = ENCODE(group);
+}
+
+void
+base64_encode_init(struct base64_encode_ctx *ctx)
+{
+ ctx->word = ctx->bits = 0;
+}
+
+/* Encodes a single byte. */
+unsigned
+base64_encode_single(struct base64_encode_ctx *ctx,
+ uint8_t *dst,
+ uint8_t src)
+{
+ unsigned done = 0;
+ unsigned word = ctx->word << 8 | src;
+ unsigned bits = ctx->bits + 8;
+
+ while (bits >= 6)
+ {
+ bits -= 6;
+ dst[done++] = ENCODE(word >> bits);
+ }
+
+ ctx->bits = bits;
+ ctx->word = word;
+
+ assert(done <= 2);
+
+ return done;
+}
+
+/* Returns the number of output characters. DST should point to an
+ * area of size at least BASE64_ENCODE_LENGTH(length). */
+unsigned
+base64_encode_update(struct base64_encode_ctx *ctx,
+ uint8_t *dst,
+ unsigned length,
+ const uint8_t *src)
+{
+ unsigned done = 0;
+ unsigned left = length;
+ unsigned left_over;
+ unsigned bulk;
+
+ while (ctx->bits && left)
+ {
+ left--;
+ done += base64_encode_single(ctx, dst + done, *src++);
+ }
+
+ left_over = left % 3;
+ bulk = left - left_over;
+
+ if (bulk)
+ {
+ assert(!(bulk % 3));
+
+ base64_encode_raw(dst + done, bulk, src);
+ done += BASE64_ENCODE_RAW_LENGTH(bulk);
+ src += bulk;
+ left = left_over;
+ }
+
+ while (left)
+ {
+ left--;
+ done += base64_encode_single(ctx, dst + done, *src++);
+ }
+
+ assert(done <= BASE64_ENCODE_LENGTH(length));
+
+ return done;
+}
+
+/* DST should point to an area of size at least
+ * BASE64_ENCODE_FINAL_SIZE */
+unsigned
+base64_encode_final(struct base64_encode_ctx *ctx,
+ uint8_t *dst)
+{
+ unsigned done = 0;
+ unsigned bits = ctx->bits;
+
+ if (bits)
+ {
+ dst[done++] = ENCODE(ctx->word << (6 - ctx->bits));
+ for (; bits < 6; bits += 2)
+ dst[done++] = '=';
+
+ ctx->bits = 0;
+ }
+
+ assert(done <= BASE64_ENCODE_FINAL_LENGTH);
+ return done;
+}