1 files changed, 255 insertions, 0 deletions
diff --git a/sql_common.h b/sql_common.h
new file mode 100644
index 0000000..8f1844b
--- /dev/null
+++ b/sql_common.h
@@ -0,0 +1,255 @@
+/* 
+ * sql_common.h
+ * ------------
+ *
+ * Common definitions and SQL support code for Cryptech PKCS #11 engine.
+ *
+ * We could split the functions out of this into a separate .c file,
+ * but there's no real point in doing so, and it's simpler to keep it
+ * all in one file, the build process is complex enough already.
+ *
+ * Author: Rob Austein
+ * Copyright (c) 2015, SUNET
+ * 
+ * Redistribution and use in source and binary forms, with or 
+ * without modification, are permitted provided that the following 
+ * conditions are met: 
+ * 
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ * 
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in 
+ *    the documentation and/or other materials provided with the 
+ *    distribution. 
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _SQL_COMMON_H_
+#define _SQL_COMMON_H_
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdarg.h> 
+#include <assert.h>
+
+#include <sqlite3.h>
+
+/*
+ * Placeholders for PIN length limits.  Figure out real values later.
+ */
+
+#warning Figure out PIN length limits
+#define P11_MIN_PIN_LENGTH      16
+#define P11_MAX_PIN_LENGTH      4096
+
+/*
+ * Debugging control.
+ */
+
+#ifndef DEBUG_SQL
+#define DEBUG_SQL       1
+#endif
+
+/*
+ * Default filename for SQL database lives.  Can be overriden at
+ * runtime by setting PKCS11_DATABASE environment variable.
+ */
+
+#ifndef SQL_DATABASE
+#define SQL_DATABASE ".cryptech-pkcs11.db"
+#endif
+
+/*
+ * SQL database.
+ */
+
+static sqlite3 *sqldb = NULL;
+
+/*
+ * Error checking for SQLite calls.
+ */
+
+#if DEBUG_SQL
+
+#define sql_whine(_expr_)                                               \
+  (fprintf(stderr, "%s:%u: %s returned %s\n",                           \
+           __FILE__, __LINE__, #_expr_, sqlite3_errmsg(sqldb)),         \
+   sql_breakpoint())
+
+#else  /* DEBUG_SQL */
+
+#define sql_whine(_expr_)                                               \
+  ((void) 0)
+
+#endif  /* DEBUG_SQL */
+
+#define sql_check(_good_, _expr_)                                       \
+  ((_expr_) == (_good_) ? 1 : (sql_whine(_expr_), 0))
+
+#define sql_check_ok(_expr_)    sql_check(SQLITE_OK, _expr_)
+#define sql_check_row(_expr_)   sql_check(SQLITE_ROW, _expr_)
+#define sql_check_done(_expr_)  sql_check(SQLITE_DONE, _expr_)
+#define sql_whine_step()        sql_whine(sqlite3_step())
+
+/*
+ * Hook on which to hang a debugger breakpoint on SQL errors.
+ */
+
+#if DEBUG_SQL
+static void sql_breakpoint(void)
+{
+  fprintf(stderr, "[sql_breakpoint]\n");
+}
+#endif
+
+/*
+ * Execute SQL code that doesn't require a prepared query.
+ */
+
+static int sql_exec(const char *cmd)
+{
+  char *msg = NULL;
+
+  if (sql_check_ok(sqlite3_exec(sqldb, cmd, NULL, NULL, &msg)))
+    return 1;
+
+#if DEBUG_SQL
+  if (msg != NULL)
+    fprintf(stderr, "[%s]\n", msg);
+#endif
+
+  return 0;
+}
+
+/*
+ * Initialize SQL.  This includes loading our schema, portions of
+ * which live in the temp (memory) database thus always need to be
+ * created on startup.
+ */
+
+static int sql_init(void)
+{
+  static const char schema[] =
+#include "schema.h"
+    ;
+
+  assert(sqldb == NULL);
+
+  const char * const env  = getenv("PKCS11_DATABASE");
+  const char * const home = getenv("HOME");
+  const char * const base = SQL_DATABASE;
+  int ok;
+
+  if (env != NULL) {
+    ok = sql_check_ok(sqlite3_open(env, &sqldb));
+  }
+
+  else if (home == NULL) {
+    ok = sql_check_ok(sqlite3_open(base, &sqldb));
+  }
+
+  else {
+    char fn[strlen(home) + strlen(base) + 2];
+    snprintf(fn, sizeof(fn), "%s/%s", home, base);
+    ok = sql_check_ok(sqlite3_open(fn, &sqldb));
+  }
+
+  return ok && sql_exec(schema);
+}
+
+/*
+ * Shut down SQL.
+ *
+ * Yes, this can return failure, although it's not clear what we're
+ * meant to do about that if the application is going to shut down
+ * regardless of what we do.  I guess we could loop retrying a few
+ * times for errors like SQLITE_BUSY, but that's about it.
+ */
+
+static int sql_fini(void)
+{
+  if (!sql_check_ok(sqlite3_close(sqldb)))
+    return 0;
+
+  sqldb = NULL;
+  return 1;
+}
+
+/*
+ * GCC attribute declaration to help catch format string errors,
+ * ignored by other compilers.
+ */
+
+#ifdef __GNUC__
+static int sql_prepare(sqlite3_stmt **q,
+                       const char *format, ...)
+  __attribute__ ((format (printf, 2, 3)));
+#endif
+
+/*
+ * Prepare an SQLite3 query, using vsnprintf() to format the query.
+ *
+ *             WARNING WARNING WARNING WARNING
+ *
+ * Do not use this formatting mechanism for anything involving
+ * user-supplied data.  It's only intended to handle things like
+ * selecting between two parallel table structures or queries using
+ * manifest constants that are only available in C header files.
+ */
+
+static int sql_prepare(sqlite3_stmt **q, const char *format, ...)
+{
+  char buffer[2048];
+  va_list ap;
+  size_t n;
+
+  va_start(ap, format);
+  n = vsnprintf(buffer, sizeof(buffer), format, ap);
+  va_end(ap);
+
+  if (n >= sizeof(buffer))
+    return SQLITE_TOOBIG;
+
+  return sqlite3_prepare_v2(sqldb, buffer, -1, q, NULL);
+}
+
+/*
+ * This idiom occurs frequently, bundle it so we have the option of
+ * doing it along with the normal conditional control flow that SQL
+ * queries seem to follow.
+ */
+
+static int sql_finalize_and_clear(sqlite3_stmt **q)
+{
+  assert(q != NULL);
+
+  int err = sqlite3_finalize(*q);
+
+  if (err != SQLITE_OK)
+    return err;
+
+  *q = NULL;
+  return SQLITE_OK;
+}
+
+#endif /* _SQL_COMMON_H_ */
+
+/*
+ * Local variables:
+ * indent-tabs-mode: nil
+ * End:
+ */