Backport the word64 support for encode/decode

OpenSIPS · Aug 31, 2018 · c245e77 · c245e77
1 parent 107e1f6
commit c245e77
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Showing 2 changed files with 131 additions and 1 deletion.
diff --git a/ut.c b/ut.c
@@ -195,6 +195,9 @@ int parse_reply_codes( str *options_reply_codes_str,
 static const char base64digits[] =
 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
+static const char word64digits[] =
+"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+.";
+
 #define BAD     ((unsigned char)-1)
 static const unsigned char base64val[] = {
 BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
@@ -204,10 +207,39 @@ BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD, 62, BAD,BAD,BAD, 63,
 BAD,  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,BAD, BAD,BAD,BAD,BAD,
 BAD, 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,BAD, BAD,BAD,BAD,BAD
+41, 42, 43, 44,  45, 46, 47, 48,  49, 50, 51,BAD, BAD,BAD,BAD,BAD,
+
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD
 };
 #define DECODE64(c)  (isascii(c) ? base64val[c] : BAD)
 
+static const unsigned char word64val[] = {
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD, 62, BAD,BAD, 63,BAD,
+52, 53, 54, 55,  56, 57, 58, 59,  60, 61,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,  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,BAD, BAD,BAD,BAD,BAD,
+BAD, 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,BAD, BAD,BAD,BAD,BAD,
+
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD
+};
+
 
 /* function that encodes to base64
  * output buffer is assumed to have the right length */
@@ -239,6 +271,35 @@ void base64encode(unsigned char *out, unsigned char *in, int inlen)
 	}
 }
 
+/* function that encodes to word64
+ * output buffer is assumed to have the right length */
+void word64encode(unsigned char *out, unsigned char *in, int inlen)
+{
+	for (; inlen >= 3; inlen -= 3)
+	{
+		*out++ = word64digits[in[0] >> 2];
+		*out++ = word64digits[((in[0] << 4) & 0x30) | (in[1] >> 4)];
+		*out++ = word64digits[((in[1] << 2) & 0x3c) | (in[2] >> 6)];
+		*out++ = word64digits[in[2] & 0x3f];
+		in += 3;
+	}
+
+	if (inlen > 0)
+	{
+		unsigned char fragment;
+
+		*out++ = word64digits[in[0] >> 2];
+		fragment = (in[0] << 4) & 0x30;
+
+		if (inlen > 1)
+			fragment |= in[1] >> 4;
+
+		*out++ = word64digits[fragment];
+		*out++ = (inlen < 2) ? '-' : word64digits[(in[1] << 2) & 0x3c];
+		*out++ = '-';
+	}
+}
+
 /* function that decodes from base64
  * output buffer is assumed to have the right length */
 int base64decode(unsigned char *out,unsigned char *in,int len)
@@ -298,3 +359,61 @@ int base64decode(unsigned char *out,unsigned char *in,int len)
 	return out_len;
 }
 
+/* function that decodes from word64
+ * output buffer is assumed to have the right length */
+int word64decode(unsigned char *out, unsigned char *in, int len)
+{
+	int i=0;
+	unsigned char c1,c2,c3,c4;
+	int out_len=0;
+
+	while (len > i)
+	{
+		do
+		{
+			c1 = word64val[in[i++]];
+		} while (i<len && c1 == BAD);
+
+		if (c1 == BAD)
+			break;
+
+		do
+		{
+			c2 = word64val[in[i++]];
+		} while (i<len && c2 == BAD);
+
+		if (c2 == BAD)
+			break;
+
+		out[out_len++] = (c1 << 2) | ((c2 & 0x30) >> 4);
+
+		do
+		{
+			c3 = in[i++];
+			if (c3 == 61)
+				return out_len;
+
+			c3 = word64val[c3];
+		} while (i<len && c3 == BAD);
+
+		if (c3 == BAD)
+			break;
+
+		out[out_len++] = ((c2 & 0x0f) << 4) | ((c3 & 0x3c) >> 2);
+
+		do
+		{
+			c4 = in[i++];
+			if (c4 == 61)
+				return out_len;
+			c4 = word64val[c4];
+		} while (i<len && c4 == BAD);
+
+		if (c4 == BAD)
+			break;
+
+		out[out_len++] = ((c3 & 0x03) << 6) | c4;
+	}
+
+	return out_len;
+}
diff --git a/ut.h b/ut.h
@@ -998,15 +998,26 @@ int parse_reply_codes( str *options_reply_codes_str,
 void base64encode(unsigned char *out, unsigned char *in, int inlen);
 int base64decode(unsigned char *out,unsigned char *in,int len);
 
+/*
+ * "word64" is a combination between:
+ *   - RFC 3261-compatible "word" token characters
+ *   - modulo-64 encoding of base64
+ */
+void word64encode(unsigned char *out, unsigned char *in, int inlen);
+int word64decode(unsigned char *out, unsigned char *in, int len);
+
 static inline int calc_base64_encode_len(int len)
 {
 	return (len/3 + (len%3?1:0))*4;
 }
+#define calc_word64_encode_len calc_base64_encode_len
 
 static inline int calc_max_base64_decode_len(int len)
 {
 	return len*3/4;
 }
 
+#define calc_max_word64_decode_len calc_max_base64_decode_len
+
 
 #endif