Now that crypto_rand() cannot fail, it should return void.

src/common/crypto.c

@@ -270,8 +270,7 @@ crypto_init_siphash_key(void)
   if (have_seeded_siphash)
     return 0;
 
-  if (crypto_rand((char*) &key, sizeof(key)) < 0)
+  crypto_rand((char*) &key, sizeof(key));
-    return -1;
   siphash_set_global_key(&key);
   have_seeded_siphash = 1;
   return 0;
@@ -2368,27 +2367,26 @@ crypto_seed_rng(void)
 /** Write <b>n</b> bytes of strong random data to <b>to</b>. Return 0 on
  * success, -1 on failure, with support for mocking for unit tests.
  */
-MOCK_IMPL(int,
+MOCK_IMPL(void,
 crypto_rand, (char *to, size_t n))
 {
-  return crypto_rand_unmocked(to, n);
+  crypto_rand_unmocked(to, n);
 }
 
 /** Write <b>n</b> bytes of strong random data to <b>to</b>. Return 0 on
  * success, -1 on failure.  Most callers will want crypto_rand instead.
  */
-int
+void
 crypto_rand_unmocked(char *to, size_t n)
 {
   int r;
   if (n == 0)
-    return 0;
+    return;
 
   tor_assert(n < INT_MAX);
   tor_assert(to);
   r = RAND_bytes((unsigned char*)to, (int)n);
   tor_assert(r >= 0);
-  return 0;
 }
 
 /** Return a pseudorandom integer, chosen uniformly from the values

src/common/crypto.h

@@ -260,8 +260,8 @@ int crypto_expand_key_material_rfc5869_sha256(
 
 /* random numbers */
 int crypto_seed_rng(void) ATTR_WUR;
-MOCK_DECL(int,crypto_rand,(char *to, size_t n));
+MOCK_DECL(void,crypto_rand,(char *to, size_t n));
-int crypto_rand_unmocked(char *to, size_t n);
+void crypto_rand_unmocked(char *to, size_t n);
 int crypto_strongest_rand(uint8_t *out, size_t out_len);
 int crypto_rand_int(unsigned int max);
 int crypto_rand_int_range(unsigned int min, unsigned int max);

src/common/crypto_curve25519.c

@@ -113,8 +113,7 @@ curve25519_rand_seckey_bytes(uint8_t *out, int extra_strong)
 {
   uint8_t k_tmp[CURVE25519_SECKEY_LEN];
 
-  if (crypto_rand((char*)out, CURVE25519_SECKEY_LEN) < 0)
+  crypto_rand((char*)out, CURVE25519_SECKEY_LEN);
-    return -1;
   if (extra_strong && !crypto_strongest_rand(k_tmp, CURVE25519_SECKEY_LEN)) {
     /* If they asked for extra-strong entropy and we have some, use it as an
      * HMAC key to improve not-so-good entropy rather than using it directly,

src/common/tortls.c

@@ -601,8 +601,7 @@ tor_tls_create_certificate(crypto_pk_t *rsa,
     goto error;
 
   { /* our serial number is 8 random bytes. */
-    if (crypto_rand((char *)serial_tmp, sizeof(serial_tmp)) < 0)
+    crypto_rand((char *)serial_tmp, sizeof(serial_tmp));
-      goto error;
     if (!(serial_number = BN_bin2bn(serial_tmp, sizeof(serial_tmp), NULL)))
       goto error;
     if (!(BN_to_ASN1_INTEGER(serial_number, X509_get_serialNumber(x509))))

src/or/config.c

@@ -7329,8 +7329,7 @@ init_cookie_authentication(const char *fname, const char *header,
 
   /* Generate the cookie */
   *cookie_out = tor_malloc(cookie_len);
-  if (crypto_rand((char *)*cookie_out, cookie_len) < 0)
+  crypto_rand((char *)*cookie_out, cookie_len);
-    goto done;
 
   /* Create the string that should be written on the file. */
   memcpy(cookie_file_str, header, strlen(header));

src/or/connection_or.c

@@ -2290,8 +2290,7 @@ connection_or_send_auth_challenge_cell(or_connection_t *conn)
 
   auth_challenge_cell_t *ac = auth_challenge_cell_new();
 
-  if (crypto_rand((char*)ac->challenge, sizeof(ac->challenge)) < 0)
+  crypto_rand((char*)ac->challenge, sizeof(ac->challenge));
-    goto done;
 
   auth_challenge_cell_add_methods(ac, AUTHTYPE_RSA_SHA256_TLSSECRET);
   auth_challenge_cell_set_n_methods(ac,

src/or/control.c

@@ -3418,8 +3418,7 @@ handle_control_authchallenge(control_connection_t *conn, uint32_t len,
     tor_free(client_nonce);
     return -1;
   }
-  const int fail = crypto_rand(server_nonce, SAFECOOKIE_SERVER_NONCE_LEN);
+  crypto_rand(server_nonce, SAFECOOKIE_SERVER_NONCE_LEN);
-  tor_assert(!fail);
 
   /* Now compute and send the server-to-controller response, and the
    * server's nonce. */

src/or/ext_orport.c

@@ -193,8 +193,7 @@ handle_client_auth_nonce(const char *client_nonce, size_t client_nonce_len,
     return -1;
 
   /* Get our nonce */
-  if (crypto_rand(server_nonce, EXT_OR_PORT_AUTH_NONCE_LEN) < 0)
+  crypto_rand(server_nonce, EXT_OR_PORT_AUTH_NONCE_LEN);
-    return -1;
 
   { /* set up macs */
     size_t hmac_s_msg_len = strlen(EXT_OR_PORT_AUTH_SERVER_TO_CLIENT_CONST) +

src/or/onion_fast.c

@@ -30,10 +30,7 @@ fast_onionskin_create(fast_handshake_state_t **handshake_state_out,
 {
   fast_handshake_state_t *s;
   *handshake_state_out = s = tor_malloc(sizeof(fast_handshake_state_t));
-  if (crypto_rand((char*)s->state, sizeof(s->state)) < 0) {
+  crypto_rand((char*)s->state, sizeof(s->state));
-    tor_free(s);
-    return -1;
-  }
   memcpy(handshake_out, s->state, DIGEST_LEN);
   return 0;
 }
@@ -56,8 +53,7 @@ fast_server_handshake(const uint8_t *key_in, /* DIGEST_LEN bytes */
   size_t out_len;
   int r = -1;
 
-  if (crypto_rand((char*)handshake_reply_out, DIGEST_LEN)<0)
+  crypto_rand((char*)handshake_reply_out, DIGEST_LEN);
-    return -1;
 
   memcpy(tmp, key_in, DIGEST_LEN);
   memcpy(tmp+DIGEST_LEN, handshake_reply_out, DIGEST_LEN);

src/or/rendclient.c

@@ -65,11 +65,7 @@ rend_client_send_establish_rendezvous(origin_circuit_t *circ)
   tor_assert(circ->rend_data);
   log_info(LD_REND, "Sending an ESTABLISH_RENDEZVOUS cell");
 
-  if (crypto_rand(circ->rend_data->rend_cookie, REND_COOKIE_LEN) < 0) {
+  crypto_rand(circ->rend_data->rend_cookie, REND_COOKIE_LEN);
-    log_warn(LD_BUG, "Internal error: Couldn't produce random cookie.");
-    circuit_mark_for_close(TO_CIRCUIT(circ), END_CIRC_REASON_INTERNAL);
-    return -1;
-  }
 
   /* Set timestamp_dirty, because circuit_expire_building expects it,
    * and the rend cookie also means we've used the circ. */

src/or/rendcommon.c

@@ -268,11 +268,7 @@ rend_encrypt_v2_intro_points_basic(char **encrypted_out,
   tor_assert(client_cookies && smartlist_len(client_cookies) > 0);
 
   /* Generate session key. */
-  if (crypto_rand(session_key, CIPHER_KEY_LEN) < 0) {
+  crypto_rand(session_key, CIPHER_KEY_LEN);
-    log_warn(LD_REND, "Unable to generate random session key to encrypt "
-                      "introduction point string.");
-    goto done;
-  }
 
   /* Determine length of encrypted introduction points including session
    * keys. */
@@ -334,11 +330,7 @@ rend_encrypt_v2_intro_points_basic(char **encrypted_out,
            REND_BASIC_AUTH_CLIENT_MULTIPLE;
        i < REND_BASIC_AUTH_CLIENT_MULTIPLE - 1; i++) {
     client_part = tor_malloc_zero(REND_BASIC_AUTH_CLIENT_ENTRY_LEN);
-    if (crypto_rand(client_part, REND_BASIC_AUTH_CLIENT_ENTRY_LEN) < 0) {
+    crypto_rand(client_part, REND_BASIC_AUTH_CLIENT_ENTRY_LEN);
-      log_warn(LD_REND, "Unable to generate fake client entry.");
-      tor_free(client_part);
-      goto done;
-    }
     smartlist_add(encrypted_session_keys, client_part);
   }
   /* Sort smartlist and put elements in result in order. */

src/test/test_extorport.c

@@ -309,15 +309,14 @@ test_ext_or_cookie_auth(void *arg)
   tor_free(client_hash2);
 }
 
-static int
+static void
 crypto_rand_return_tse_str(char *to, size_t n)
 {
   if (n != 32) {
     TT_FAIL(("Asked for %d bytes, not 32", (int)n));
-    return -1;
+    return;
   }
   memcpy(to, "te road There is always another ", 32);
-  return 0;
 }
 
 static void