decode data from shells keys

Makefile

@@ -1,11 +1,11 @@
 CC = gcc
-CFLAGS = -g -Wall -DERR -DLOG -DSHELLS
+CFLAGS = -Wall -DERR -DLOG -DSHELLS
 
 .PHONY: init clean
 
-init: init.o wjson.o wxmpp.o wxmpp_handlers.o shells.o libds
+init: init.o wjson.o wxmpp.o wxmpp_handlers.o shells.o base64.o libds
 	make -C libds
-	$(CC) init.o wjson.o wxmpp.o wxmpp_handlers.o shells.o libds/*.o -o init -ljansson -lstrophe
+	$(CC) init.o wjson.o wxmpp.o wxmpp_handlers.o shells.o base64.o libds/*.o -o init -ljansson -lstrophe
 
 init.o: init.c winternals/winternals.h wjson/wjson.h wxmpp/wxmpp.h
 	$(CC) $(CFLAGS) -c init.c
@@ -22,5 +22,8 @@ wxmpp_handlers.o: wxmpp/wxmpp_handlers.c wxmpp/wxmpp.h wxmpp/wxmpp_handlers.h wi
 shells.o: shells/shells.c winternals/winternals.h shells/shells.h
 	$(CC) $(CFLAGS) -c shells/shells.c
 
+base64.o: base64/base64.c base64/base64.h
+	$(CC) $(CFLAGS) -c base64/base64.c
+
 clean:
 	rm -f *.o init

base64/base64.c

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2006 Ryan Martell. (rdm4@martellventures.com)
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * @brief Base64 encode/decode
+ * @author Ryan Martell <rdm4@martellventures.com> (with lots of Michael)
+ */
+
+#include <stdio.h>
+#include <limits.h>
+//#include "utils.h"
+#include "base64.h"
+
+/* ---------------- private code */
+static const uint8_t map2[] =
+{
+  0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36,
+  0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff,
+  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x01,
+  0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
+  0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
+  0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19,
+  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1a, 0x1b,
+  0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
+  0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+  0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33
+};
+
+int base64_decode(uint8_t *out, const char *in, int out_size)
+{
+  int i, v;
+  uint8_t *dst = out;
+
+  v = 0;
+  for (i = 0; in[i] && in[i] != '='; i++) {
+    unsigned int index= in[i]-43;
+    if (index>=SIZEOF_ARRAY(map2) || map2[index] == 0xff)
+      return -1;
+    v = (v << 6) + map2[index];
+    if (i & 3) {
+      if (dst - out < out_size) {
+        *dst++ = v >> (6 - 2 * (i & 3));
+      }
+    }
+  }
+
+  return dst - out;
+}
+
+/*****************************************************************************
+* b64_encode: Stolen from VLC's http.c.
+* Simplified by Michael.
+* Fixed edge cases and made it work from data (vs. strings) by Ryan.
+*****************************************************************************/
+
+char *base64_encode(char *out, int out_size, const uint8_t *in, int in_size)
+{
+  static const char b64[] =
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+  char *ret, *dst;
+  unsigned i_bits = 0;
+  int i_shift = 0;
+  int bytes_remaining = in_size;
+
+  if (in_size >= UINT_MAX / 4 ||
+    out_size < BASE64_SIZE(in_size))
+    return NULL;
+  ret = dst = out;
+  while (bytes_remaining) {
+    i_bits = (i_bits << 8) + *in++;
+    bytes_remaining--;
+    i_shift += 8;
+
+    do {
+      *dst++ = b64[(i_bits << 6 >> i_shift) & 0x3f];
+      i_shift -= 6;
+    } while (i_shift > 6 || (bytes_remaining == 0 && i_shift > 0));
+  }
+  while ((dst - ret) & 3)
+    *dst++ = '=';
+  *dst = '\0';
+
+  return ret;
+}

base64/base64.h

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2006 Ryan Martell. (rdm4@martellventures.com)
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef BASE64_H
+#define BASE64_H
+
+#include <stdint.h>
+
+#define SIZEOF_ARRAY(arr) (sizeof(arr) / sizeof(arr[0]))
+
+/**
+ * Decode a base64-encoded string.
+ *
+ * @param out      buffer for decoded data
+ * @param in       null-terminated input string
+ * @param out_size size in bytes of the out buffer, must be at
+ *                 least 3/4 of the length of in
+ * @return         number of bytes written, or a negative value in case of
+ *                 invalid input
+ */
+int base64_decode(uint8_t *out, const char *in, int out_size);
+
+/**
+ * Encode data to base64 and null-terminate.
+ *
+ * @param out      buffer for encoded data
+ * @param out_size size in bytes of the output buffer, must be at
+ *                 least BASE64_SIZE(in_size)
+ * @param in_size  size in bytes of the 'in' buffer
+ * @return         'out' or NULL in case of error
+ */
+char *base64_encode(char *out, int out_size, const uint8_t *in, int in_size);
+
+/**
+ * Calculate the output size needed to base64-encode x bytes.
+ */
+#define BASE64_SIZE(x) (((x)+2) / 3 * 4 + 1)
+
+#endif /* BASE64_H */

shells/shells.c

@@ -4,10 +4,12 @@
 
 #include <strophe.h> /* Strophe XMPP stuff */
 #include <strings.h> /* strncasecmp */
-#include <string.h>
+#include <string.h>  /* strlen */
+#include <stdlib.h>  /* malloc */
 
 #include "../winternals/winternals.h" /* logs and errs */
 #include "../wxmpp/wxmpp.h"           /* WNS */
+#include "../base64/base64.h"         /* encode decode */
 #include "shells.h"                   /* shells module api */
 
 #ifdef SHELLS
@@ -87,6 +89,12 @@ void shells_keys(xmpp_stanza_t *stanza, xmpp_conn_t *const conn, void *const use
     return;
   }
 
+  /* Decode */
+  int dec_size = strlen(data_str) * 3 / 4 + 1; /* decoded data length */
+  uint8_t *decoded = (uint8_t *)calloc(dec_size, sizeof(uint8_t)); /* decoded data */
+  base64_decode(decoded, data_str, dec_size); /* decode */
+  werr("decoded data = %s\n\n\n", decoded);
+
   /* Send back keys */
   xmpp_ctx_t *ctx = (xmpp_ctx_t*)userdata; /* Strophe context */