Use simpler arc4random instead of /dev/urandom

[dht-bootstrap.git] / dht-bootstrap.c

diff --git a/dht-bootstrap.c b/dht-bootstrap.c
index de5bb395c5416b1412712d76e3688f519a1b2092..28f3fd26e4281a4b5545a6b50f6a5964bb2113b8 100644 (file)
--- a/dht-bootstrap.c
+++ b/dht-bootstrap.c
@@ -20,22 +20,19 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 */
 
-#include <arpa/inet.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <netdb.h>
 #include <netinet/in.h>
+#include <poll.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/socket.h>
-#include <sys/time.h>
-#include <sys/types.h>
 #include <time.h>
 #include <unistd.h>
 
-#define MAX(x, y) ((x) >= (y) ? (x) : (y))
 #define MIN(x, y) ((x) <= (y) ? (x) : (y))
 
 static int
@@ -357,9 +354,7 @@ send_request(struct circular_list *list, int dopop, int doping, int want)
         return send_ping((struct sockaddr *)&ss, sslen, ttid, 4);
     } else {
         unsigned char id[20];
-        int i;
-        for (i = 0; i < 20; i++)
-            id[i] = random() & 0xFF;
+        arc4random_buf(id, sizeof id);
         make_tid(ttid, "fn", 0);
         debugf("Sending find_node.\n");
         return send_find_node((struct sockaddr *)&ss, sslen, ttid, 4, id, want);
@@ -445,26 +440,7 @@ main(int argc, char **argv)
         dht_socket6 = newSock(ipv6addr, port);
     }
 
-    int rc = 0;
-    {
-        int fd = open("/dev/urandom", O_RDONLY);
-        if (fd < 0) {
-            perror("open(random)");
-            exit(1);
-        }
-
-        rc = read(fd, myid, 20);
-        if (rc < 20) {
-            perror("open(random)");
-            exit(1);
-        }
-
-        unsigned int seed;
-        rc = read(fd, &seed, sizeof(seed));
-        srandom(seed);
-
-        close(fd);
-    }
+    arc4random_buf(myid, sizeof myid);
 
     memcpy(my_v, "1:v4:JB\0\0", 9);
     have_v = 1;
@@ -472,6 +448,7 @@ main(int argc, char **argv)
     if (!quiet)
         dht_debug = stdout;
 
+    int rc = 0;
     unsigned char ttid[4];
 
     while (i < argc) {
@@ -508,23 +485,20 @@ main(int argc, char **argv)
     token_bucket_time = time(NULL);
     token_bucket_tokens = MAX_TOKEN_BUCKET_TOKENS;
     int send4 = 0;
+    struct pollfd fds[2];
+    fds[0].fd = dht_socket;
+    fds[0].events = POLLIN;
+    fds[1].fd = dht_socket6;
+    fds[1].events = POLLIN;
 
     while (1) {
-        struct timeval tv;
-        fd_set readfds;
-
+        int tv_sec = 0;
         if ((dht_socket >= 0 && list_elements(&v4_confirmed) <= 16) ||
             (dht_socket6 >= 0 && list_elements(&v6_confirmed) <= 16))
-            tv.tv_sec = 0;
+            tv_sec = 0;
         else
-            tv.tv_sec = random() % 30;
-        tv.tv_usec = random() % 1000000;
-
-        FD_ZERO(&readfds);
-        if (dht_socket >= 0)
-            FD_SET(dht_socket, &readfds);
-        if (dht_socket6 >= 0)
-            FD_SET(dht_socket6, &readfds);
+            tv_sec = random() % 30;
+        int tv_msec = random() % 1000;
 
         if (dht_debug)
             debugf(
@@ -534,13 +508,11 @@ main(int argc, char **argv)
                 list_elements(&v4_new),
                 list_elements(&v6_new));
 
-        int rc = select(MAX(dht_socket, dht_socket6) + 1, &readfds, NULL, NULL, &tv);
+        int rc = poll(fds, 2, tv_sec * 1000 + tv_msec);
 
         if (rc < 0) {
-            if (errno != EINTR) {
-                perror("select");
-                sleep(1);
-            }
+            perror("poll");
+            sleep(1);
         }
 
         if (rc > 0) {
@@ -557,10 +529,20 @@ main(int argc, char **argv)
             struct sockaddr_storage source_storage;
             struct sockaddr *source = (struct sockaddr *)&source_storage;
             socklen_t sourcelen = sizeof(source_storage);
-            if (dht_socket >= 0 && FD_ISSET(dht_socket, &readfds)) {
-                rc = recvfrom(dht_socket, buf, 1536, 0, source, &sourcelen);
-            } else if (dht_socket6 >= 0 && FD_ISSET(dht_socket6, &readfds)) {
-                rc = recvfrom(dht_socket6, buf, 1536, 0, source, &sourcelen);
+            if (fds[0].revents != 0) {
+                if ((fds[0].revents & (POLLERR | POLLNVAL)) > 0) {
+                    fprintf(stderr, "error in fds[0]");
+                    rc = -1;
+                } else {
+                    rc = recvfrom(dht_socket, buf, 1536, 0, source, &sourcelen);
+                }
+            } else if (fds[1].revents != 0) {
+                if ((fds[1].revents & (POLLERR | POLLNVAL)) > 0) {
+                    fprintf(stderr, "error in fds[1]");
+                    rc = -1;
+                } else {
+                    rc = recvfrom(dht_socket6, buf, 1536, 0, source, &sourcelen);
+                };
             }
 
             if (rc < 0 || sourcelen > sizeof(struct sockaddr_storage))