Merge remote-tracking branch 'remotes/rth/tags/pull-rng-20190522' into staging

Introduce qemu_guest_getrandom.
Use qemu_guest_getrandom in aspeed, nrf51, bcm2835, exynos4210 rng devices.
Use qemu_guest_getrandom in target/ppc darn instruction.
Support ARMv8.5-RNG extension.
Support x86 RDRAND extension.

Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Laurent Vivier <laurent@vivier.eu>

# gpg: Signature made Wed 22 May 2019 19:36:43 BST
# gpg:                using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg:                issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-rng-20190522: (25 commits)
  target/i386: Implement CPUID_EXT_RDRAND
  target/ppc: Use qemu_guest_getrandom for DARN
  target/ppc: Use gen_io_start/end around DARN
  target/arm: Implement ARMv8.5-RNG
  target/arm: Put all PAC keys into a structure
  hw/misc/exynos4210_rng: Use qemu_guest_getrandom
  hw/misc/bcm2835_rng: Use qemu_guest_getrandom_nofail
  hw/misc/nrf51_rng: Use qemu_guest_getrandom_nofail
  aspeed/scu: Use qemu_guest_getrandom_nofail
  linux-user: Remove srand call
  linux-user/aarch64: Use qemu_guest_getrandom for PAUTH keys
  linux-user: Use qemu_guest_getrandom_nofail for AT_RANDOM
  linux-user: Call qcrypto_init if not using -seed
  linux-user: Initialize pseudo-random seeds for all guest cpus
  cpus: Initialize pseudo-random seeds for all guest cpus
  util: Add qemu_guest_getrandom and associated routines
  ui/vnc: Use gcrypto_random_bytes for start_auth_vnc
  ui/vnc: Split out authentication_failed
  crypto: Change the qcrypto_random_bytes buffer type to void*
  crypto: Use getrandom for qcrypto_random_bytes
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 23 insertions, 30 deletions

diff --git a/ui/vnc.c b/ui/vnc.c
index 1871422e1d..d83f4a6ff9 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -43,6 +43,7 @@
 #include "crypto/hash.h"
 #include "crypto/tlscredsanon.h"
 #include "crypto/tlscredsx509.h"
+#include "crypto/random.h"
 #include "qom/object_interfaces.h"
 #include "qemu/cutils.h"
 #include "io/dns-resolver.h"
@@ -2535,14 +2536,16 @@ void start_client_init(VncState *vs)
     vnc_read_when(vs, protocol_client_init, 1);
 }
 
-static void make_challenge(VncState *vs)
+static void authentication_failed(VncState *vs)
 {
-    int i;
-
-    srand(time(NULL)+getpid()+getpid()*987654+rand());
-
-    for (i = 0 ; i < sizeof(vs->challenge) ; i++)
-        vs->challenge[i] = (int) (256.0*rand()/(RAND_MAX+1.0));
+    vnc_write_u32(vs, 1); /* Reject auth */
+    if (vs->minor >= 8) {
+        static const char err[] = "Authentication failed";
+        vnc_write_u32(vs, sizeof(err));
+        vnc_write(vs, err, sizeof(err));
+    }
+    vnc_flush(vs);
+    vnc_client_error(vs);
 }
 
 static int protocol_client_auth_vnc(VncState *vs, uint8_t *data, size_t len)
@@ -2609,21 +2612,23 @@ static int protocol_client_auth_vnc(VncState *vs, uint8_t *data, size_t len)
     return 0;
 
 reject:
-    vnc_write_u32(vs, 1); /* Reject auth */
-    if (vs->minor >= 8) {
-        static const char err[] = "Authentication failed";
-        vnc_write_u32(vs, sizeof(err));
-        vnc_write(vs, err, sizeof(err));
-    }
-    vnc_flush(vs);
-    vnc_client_error(vs);
+    authentication_failed(vs);
     qcrypto_cipher_free(cipher);
     return 0;
 }
 
 void start_auth_vnc(VncState *vs)
 {
-    make_challenge(vs);
+    Error *err = NULL;
+
+    if (qcrypto_random_bytes(vs->challenge, sizeof(vs->challenge), &err)) {
+        trace_vnc_auth_fail(vs, vs->auth, "cannot get random bytes",
+                            error_get_pretty(err));
+        error_free(err);
+        authentication_failed(vs);
+        return;
+    }
+
     /* Send client a 'random' challenge */
     vnc_write(vs, vs->challenge, sizeof(vs->challenge));
     vnc_flush(vs);
@@ -2638,13 +2643,7 @@ static int protocol_client_auth(VncState *vs, uint8_t *data, size_t len)
      * must pick the one we sent. Verify this */
     if (data[0] != vs->auth) { /* Reject auth */
        trace_vnc_auth_reject(vs, vs->auth, (int)data[0]);
-       vnc_write_u32(vs, 1);
-       if (vs->minor >= 8) {
-           static const char err[] = "Authentication failed";
-           vnc_write_u32(vs, sizeof(err));
-           vnc_write(vs, err, sizeof(err));
-       }
-       vnc_client_error(vs);
+       authentication_failed(vs);
     } else { /* Accept requested auth */
        trace_vnc_auth_start(vs, vs->auth);
        switch (vs->auth) {
@@ -2673,13 +2672,7 @@ static int protocol_client_auth(VncState *vs, uint8_t *data, size_t len)
 
        default: /* Should not be possible, but just in case */
            trace_vnc_auth_fail(vs, vs->auth, "Unhandled auth method", "");
-           vnc_write_u8(vs, 1);
-           if (vs->minor >= 8) {
-               static const char err[] = "Authentication failed";
-               vnc_write_u32(vs, sizeof(err));
-               vnc_write(vs, err, sizeof(err));
-           }
-           vnc_client_error(vs);
+           authentication_failed(vs);
        }
     }
     return 0;