Return if ssleay_rand_add called with zero num.

[openssl.git] / crypto / rand / md_rand.c

diff --git a/crypto/rand/md_rand.c b/crypto/rand/md_rand.c
index f9583324e9bdd8da8e063acfbef6ec8f29ebf979..67ac5ac92721293bbaeb41efa7b41cdfa969e33d 100644 (file)
--- a/crypto/rand/md_rand.c
+++ b/crypto/rand/md_rand.c
@@ -123,6 +123,13 @@
 
 #include "e_os.h"
 
+#if !(defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYSNAME_DSPBIOS))
+# include <sys/time.h>
+#endif
+#if defined(OPENSSL_SYS_VXWORKS)
+# include <time.h>
+#endif
+
 #include <openssl/crypto.h>
 #include <openssl/rand.h>
 #include "rand_lcl.h"
@@ -160,6 +167,8 @@ int rand_predictable=0;
 
 const char RAND_version[]="RAND" OPENSSL_VERSION_PTEXT;
 
+static void rand_hw_seed(EVP_MD_CTX *ctx);
+
 static void ssleay_rand_cleanup(void);
 static int ssleay_rand_seed(const void *buf, int num);
 static int ssleay_rand_add(const void *buf, int num, double add_entropy);
@@ -203,6 +212,9 @@ static int ssleay_rand_add(const void *buf, int num, double add)
        int do_not_lock;
        int rv = 0;
 
+       if (!num)
+               return;
+
        /*
         * (Based on the rand(3) manpage)
         *
@@ -359,7 +371,28 @@ static int ssleay_rand_bytes(unsigned char *buf, int num, int pseudo)
 #ifndef GETPID_IS_MEANINGLESS
        pid_t curr_pid = getpid();
 #endif
+       time_t curr_time = time(NULL);
        int do_stir_pool = 0;
+/* time value for various platforms */
+#ifdef OPENSSL_SYS_WIN32
+       FILETIME tv;
+# ifdef _WIN32_WCE
+       SYSTEMTIME t;
+       GetSystemTime(&t);
+       SystemTimeToFileTime(&t, &tv);
+# else
+       GetSystemTimeAsFileTime(&tv);
+# endif
+#elif defined(OPENSSL_SYS_VXWORKS)
+       struct timespec tv;
+       clock_gettime(CLOCK_REALTIME, &ts);
+#elif defined(OPENSSL_SYSNAME_DSPBIOS)
+       unsigned long long tv, OPENSSL_rdtsc();
+       tv = OPENSSL_rdtsc();
+#else
+       struct timeval tv;
+       gettimeofday(&tv, NULL);
+#endif
 
 #ifdef PREDICT
        if (rand_predictable)
@@ -488,11 +521,23 @@ static int ssleay_rand_bytes(unsigned char *buf, int num, int pseudo)
 #ifndef GETPID_IS_MEANINGLESS
                if (curr_pid) /* just in the first iteration to save time */
                        {
-                       if (!MD_Update(&m,(unsigned char*)&curr_pid,sizeof curr_pid))
+                       if (!MD_Update(&m,(unsigned char*)&curr_pid,
+                                      sizeof curr_pid))
                                goto err;
                        curr_pid = 0;
                        }
 #endif
+               if (curr_time) /* just in the first iteration to save time */
+                       {
+                       if (!MD_Update(&m,(unsigned char*)&curr_time,
+                                      sizeof curr_time))
+                               goto err;
+                       if (!MD_Update(&m,(unsigned char*)&tv,
+                                      sizeof tv))
+                               goto err;
+                       curr_time = 0;
+                       rand_hw_seed(&m);
+                       }
                if (!MD_Update(&m,local_md,MD_DIGEST_LENGTH))
                        goto err;
                if (!MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c)))
@@ -624,3 +669,79 @@ static int ssleay_rand_status(void)
        
        return ret;
        }
+
+/* rand_hw_seed: get seed data from any available hardware RNG.
+ * only currently supports rdrand.
+ */
+
+/* Adapted from eng_rdrand.c */
+
+#if (defined(__i386)   || defined(__i386__)   || defined(_M_IX86) || \
+     defined(__x86_64) || defined(__x86_64__) || \
+     defined(_M_AMD64) || defined (_M_X64)) && defined(OPENSSL_CPUID_OBJ)
+
+#define RDRAND_CALLS   4
+
+size_t OPENSSL_ia32_rdrand(void);
+extern unsigned int OPENSSL_ia32cap_P[];
+
+static void rand_hw_seed(EVP_MD_CTX *ctx)
+       {
+       int i;
+       if (!(OPENSSL_ia32cap_P[1] & (1<<(62-32))))
+               return;
+       for (i = 0; i < RDRAND_CALLS; i++)
+               {
+               size_t rnd;
+               rnd = OPENSSL_ia32_rdrand();
+               if (rnd == 0)
+                       return;
+               MD_Update(ctx, (unsigned char *)&rnd, sizeof(size_t));
+               }
+       }
+
+/* XOR an existing buffer with random data */
+
+void rand_hw_xor(unsigned char *buf, size_t num)
+       {
+       size_t rnd;
+       if (!(OPENSSL_ia32cap_P[1] & (1<<(62-32))))
+               return;
+       while (num >= sizeof(size_t))
+               {
+               rnd = OPENSSL_ia32_rdrand();
+               if (rnd == 0)
+                       return;
+               *((size_t *)buf) ^= rnd;
+               buf += sizeof(size_t);
+               num -= sizeof(size_t);
+               }
+       if (num)
+               {
+               rnd = OPENSSL_ia32_rdrand();
+               if (rnd == 0)
+                       return;
+               while(num)
+                       {
+                       *buf ^= rnd & 0xff;
+                       rnd >>= 8;
+                       buf++;
+                       num--;
+                       }
+               }
+       }
+
+
+#else
+
+static void rand_hw_seed(EVP_MD_CTX *ctx)
+       {
+       return;
+       }
+
+void rand_hw_xor(unsigned char *buf, size_t num)
+       {
+       return;
+       }
+
+#endif