Rename crypt_msg() / decrypt_msg() to sed_encrypt_msg() / sed_decrypt_msg() and move to ctcp.c

These functions are really specific to parsing and creating CTCP SED messages, which means they belong
in ctcp.c with the other CTCP code.

Also remove unnecessary inclusions of encrypt.h and ctcp.h.

source/ctcp.c

@@ -603,6 +603,72 @@ int server;
 	return NULL;
 }
 
+/* Make this less than the trasmittable buffer */
+#define CRYPT_BUFFER_SIZE (IRCD_BUFFER_SIZE - 50)
+
+/*
+ * sed_encrypt_msg()
+ *
+ * Encrypts a message with my_encrypt() under the given key, and encapsulates it
+ * as a CTCP SED message ready to transmit.
+ */
+char *sed_encrypt_msg(char *str, const char *key)
+{
+	static const char sed_prefix[] = { CTCP_DELIM_CHAR, 'S', 'E', 'D', ' ', 0 };
+	const size_t len = strlen(str);
+	char buffer[CRYPT_BUFFER_SIZE];
+	char *ptr;
+
+	my_encrypt(str, len, key);
+	ptr = ctcp_quote_it(str, len);
+
+	if (ptr)
+	{
+		/* The - 1 terms here are to ensure that the trailing CTCP_DELIM_CHAR
+		 * always gets added. */
+		strlcpy(buffer, sed_prefix, sizeof buffer - 1);
+		strlcat(buffer, ptr, sizeof buffer - 1);
+		strlcat(buffer, CTCP_DELIM_STR, sizeof buffer);
+		new_free(&ptr);
+	}
+	else
+		strlcpy(buffer, str, sizeof buffer);
+
+	return (m_strdup(buffer));
+}
+
+/*
+ * sed_decrypt_msg()
+ *
+ * Given a CTCP SED argument 'str', it attempts to unscramble the text
+ * into something more sane.  If the 'key' is not the one used to scramble
+ * the text, the results are unpredictable.  This is probably the point.
+ *
+ * Note that the retval MUST be at least 'BIG_BUFFER_SIZE + 1'.  This is
+ * not an oversight -- the retval is passed is to do_ctcp() which requires
+ * a big buffer to scratch around (The decrypted text could be a CTCP UTC
+ * which could expand to a larger string of text.)
+ */ 
+char *sed_decrypt_msg(const char *str, const char *key)
+{
+	char *buffer = new_malloc(BIG_BUFFER_SIZE + 1);
+	char *ptr;
+	size_t len;
+
+	ptr = ctcp_unquote_it(str, &len);
+	my_decrypt(ptr, len, key);
+
+	if (ptr)
+	{
+		strlcpy(buffer, ptr, CRYPT_BUFFER_SIZE);
+		new_free(&ptr);
+	}
+	else
+		strlcat(buffer, str, CRYPT_BUFFER_SIZE);
+
+	return buffer;
+}
+
 static char *try_decrypt(char *from, char *to, const char *msg)
 {
 	const char *key;
@@ -618,7 +684,7 @@ static char *try_decrypt(char *from, char *to, const char *msg)
 	if (!key)
 		return NULL;
 
-	return decrypt_msg(msg, key);
+	return sed_decrypt_msg(msg, key);
 }
 
 /*