# HG changeset patch
# User John "Elwin" Edwards
# Date 1382329153 25200
# Node ID f1676e81c80a772907afe2caa99c4a01589eafce
# Parent  c4304f08e35b1a9989d91e2d6fbe0734ffcb1fe7
sqlickrypt: add support for salted SHA-512 passwords, and fix NULL bug.

Passwords will now be securely encrypted with random salt.  Also avoid
storing NULL in the database, because that makes dgamelaunch segfault.

diff -r c4304f08e35b -r f1676e81c80a sqlickrypt.c
--- a/sqlickrypt.c	Sun Oct 20 19:26:39 2013 -0700
+++ b/sqlickrypt.c	Sun Oct 20 21:19:13 2013 -0700
@@ -8,6 +8,7 @@
 
 #define DATABASE "/dgldir/dgamelaunch.db"
 #define IBUFSIZE 200
+#define RANDOMSRC "/dev/urandom"
 
 /* General idea for return status:
  * 0: success
@@ -42,6 +43,41 @@
   return;
 }
 
+char encode64(unsigned char c) {
+  if (c < 26)
+    return 'a' + c;
+  else if (c < 52)
+    return 'A' + c - 26;
+  else if (c < 62)
+    return '0' + c - 52;
+  else if (c == 62)
+    return '.';
+  else
+    return '/';
+}
+
+/* Initializes a SHA-512 salt.  salt must contain at least 20 bytes. */
+void setsalt(char *salt) {
+  unsigned char rnbytes[3], rnvals[4];
+  FILE *urandom;
+  int loop;
+  salt[0] = salt[2] = salt[19] = '$'; /* Delimiters */
+  salt[1] = '6'; /* SHA-512 */
+  urandom = fopen(RANDOMSRC, "r");
+  for (loop = 0; loop < 4; loop++) {
+    fread(rnbytes, 1, 3, urandom);
+    rnvals[0] = rnbytes[0] >> 2;
+    rnvals[1] = ((rnbytes[0] & 0x03) << 4) | ((rnbytes[1] & 0xf0) >> 4);
+    rnvals[2] = ((rnbytes[1] & 0x0f) << 2) | ((rnbytes[2] & 0xc0) >> 6);
+    rnvals[3] = rnbytes[2] & 0x3f;
+    salt[loop * 4 + 3] = encode64(rnvals[0]);
+    salt[loop * 4 + 4] = encode64(rnvals[1]);
+    salt[loop * 4 + 5] = encode64(rnvals[2]);
+    salt[loop * 4 + 6] = encode64(rnvals[3]);
+  }
+  fclose(urandom);
+}
+
 int check(char *uname, char *pw) {
   char *pwhash, *comphash;
   char *query = "SELECT password FROM dglusers WHERE username=?;";
@@ -76,10 +112,11 @@
 
 int insertuser(char *uname, char *pw, char *email) {
   char *checkquery = "SELECT * FROM dglusers WHERE username = ?;";
-  char *addquery =  "INSERT INTO dglusers (username, password, email) VALUES (?, ?, ?);";
+  char *addquery =  "INSERT INTO dglusers (username, password, email, flags, env) VALUES (?, ?, ?, ?, ?);";
   int status;
   sqlite3 *db;
   sqlite3_stmt *qstmt;
+  char salt[20];
 
   opendb(&db, &qstmt, checkquery);
   /* Check for existing account in the same transaction with creating it. */
@@ -96,13 +133,16 @@
     return 3;
   }
   /* The username doesn't exist yet, so create a new account. */
+  setsalt(salt);
   sqlite3_finalize(qstmt);
   sqlite3_prepare_v2(db, addquery, -1, &qstmt, NULL);
   if (qstmt == NULL)
     cleanup(db, NULL, 3);
   sqlite3_bind_text(qstmt, 1, uname, -1, SQLITE_TRANSIENT);
-  sqlite3_bind_text(qstmt, 2, strdup(crypt(pw, pw)), -1, free);
+  sqlite3_bind_text(qstmt, 2, strdup(crypt(pw, salt)), -1, free);
   sqlite3_bind_text(qstmt, 3, email, -1, SQLITE_TRANSIENT);
+  sqlite3_bind_int(qstmt, 4, 0);
+  sqlite3_bind_text(qstmt, 5, "", -1, SQLITE_STATIC);
   status = sqlite3_step(qstmt);
   if (status != SQLITE_DONE)
     cleanup(db, qstmt, 3);
@@ -160,10 +200,10 @@
   sqlite3_stmt *qstmt;
   int status;
   char *hash;
+  char salt[20];
 
-  /* This is not a smart use of crypt, but it needs to be compatible with
-   * dgamelaunch. */
-  hash = crypt(newpw, newpw);
+  setsalt(salt);
+  hash = crypt(newpw, salt);
   opendb(&db, &qstmt, setquery);
   status = sqlite3_bind_text(qstmt, 2, uname, -1, SQLITE_TRANSIENT);
   if (status)