OS/2: Add a crypto strength randomness generator.

Not highly sophisticated or efficient but passes every test I know of for
unpredictability & generates mod_auth_digest's secret in negligible time.
Critical comment from crypto experts is more than welcome.


git-svn-id: http://svn.apache.org/repos/asf/apr/apr/trunk@61290 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 173 insertions, 0 deletions

diff --git a/misc/os2/randbyte.c b/misc/os2/randbyte.c
new file mode 100644
index 000000000..58314028b
--- /dev/null
+++ b/misc/os2/randbyte.c
@@ -0,0 +1,161 @@
+/* ====================================================================
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000-2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * 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.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ *    if any, must include the following acknowledgment:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Apache" and "Apache Software Foundation" must
+ *    not be used to endorse or promote products derived from this
+ *    software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache",
+ *    nor may "Apache" appear in their name, without prior written
+ *    permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
+ * ITS 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.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+/* The high resolution timer API provides access to the hardware timer 
+ * running at around 1.1MHz. The amount this changes in a time slice is
+ * varies randomly due to system events, hardware interrupts etc
+ */
+static UCHAR randbyte_hrtimer()
+{
+    QWORD t1, t2;
+    UCHAR byte;
+
+    DosTmrQueryTime(&t1);
+    DosSleep(5);
+    DosTmrQueryTime(&t2);
+
+    byte = (t2.ulLo - t1.ulLo) & 0xFF;
+    byte ^= (t2.ulLo - t1.ulLo) >> 8;
+    return byte;
+}
+
+
+
+/* A bunch of system information like memory & process stats.
+ * Not highly random but every bit helps....
+ */
+static UCHAR randbyte_sysinfo()
+{
+    UCHAR byte = 0;
+    UCHAR SysVars[100];
+    int b;
+
+    DosQuerySysInfo(1, QSV_FOREGROUND_PROCESS, SysVars, sizeof(SysVars));
+
+    for (b = 0; b < 100; b++) {
+        byte ^= SysVars[b];
+    }
+
+    return byte;
+}
+
+
+
+/* Similar in concept to randbyte_hrtimer() but accesses the CPU's internal
+ * counters which run at the CPU's MHz speed. We get separate 
+ * idle / busy / interrupt cycle counts which should provide very good 
+ * randomness due to interference of hardware events.
+ * This only works on newer CPUs (at least PPro or K6) and newer OS/2 versions
+ * which is why it's run-time linked.
+ */
+
+static APIRET APIENTRY(*DosPerfSysCall) (ULONG ulCommand, ULONG ulParm1,
+                                         ULONG ulParm2, ULONG ulParm3) = NULL;
+static HMODULE hDoscalls = 0;
+#define   CMD_KI_RDCNT    (0x63)
+
+typedef struct _CPUUTIL {
+    ULONG ulTimeLow;            /* Low 32 bits of time stamp      */
+    ULONG ulTimeHigh;           /* High 32 bits of time stamp     */
+    ULONG ulIdleLow;            /* Low 32 bits of idle time       */
+    ULONG ulIdleHigh;           /* High 32 bits of idle time      */
+    ULONG ulBusyLow;            /* Low 32 bits of busy time       */
+    ULONG ulBusyHigh;           /* High 32 bits of busy time      */
+    ULONG ulIntrLow;            /* Low 32 bits of interrupt time  */
+    ULONG ulIntrHigh;           /* High 32 bits of interrupt time */
+} CPUUTIL;
+
+
+static UCHAR randbyte_perf()
+{
+    UCHAR byte = 0;
+    CPUUTIL util;
+    int c;
+
+    if (hDoscalls == 0) {
+        char failed_module[20];
+        ULONG rc;
+
+        rc = DosLoadModule(failed_module, sizeof(failed_module), "DOSCALLS",
+                           &hDoscalls);
+
+        if (rc == 0) {
+            rc = DosQueryProcAddr(hDoscalls, 976, NULL, (PFN *)&DosPerfSysCall);
+
+            if (rc) {
+                DosPerfSysCall = NULL;
+            }
+        }
+    }
+
+    if (DosPerfSysCall) {
+        if (DosPerfSysCall(CMD_KI_RDCNT, (ULONG)&util, 0, 0) == 0) {
+            for (c = 0; c < sizeof(util); c++) {
+                byte ^= ((UCHAR *)&util)[c];
+            }
+        }
+        else {
+            DosPerfSysCall = NULL;
+        }
+    }
+
+    return byte;
+}
+
+
+
+static UCHAR randbyte()
+{
+    return randbyte_hrtimer() ^ randbyte_sysinfo() ^ randbyte_perf();
+}
diff --git a/misc/unix/rand.c b/misc/unix/rand.c
index ceb8c8ea6..71778c6fd 100644
--- a/misc/unix/rand.c
+++ b/misc/unix/rand.c
@@ -81,6 +81,13 @@ apr_status_t apr_generate_random_bytes(unsigned char * buf, int length)
 
     close(rnd);
 
+#elif defined(OS2)
+    static UCHAR randbyte();
+    unsigned int idx;
+
+    for (idx=0; idx<length; idx++)
+	buf[idx] = randbyte();
+
 #else  /* use truerand */
 
     extern int randbyte(void);	/* from the truerand library */
@@ -99,4 +106,9 @@ apr_status_t apr_generate_random_bytes(unsigned char * buf, int length)
 
 #undef	STR
 #undef	XSTR
+
+#ifdef OS2
+#include "../os2/randbyte.c"
+#endif
+
 #endif /* APR_HAS_RANDOM */