- djm@cvs.openbsd.org 2010/01/28 00:21:18

[openssh.git] / ssh-rand-helper.c

diff --git a/ssh-rand-helper.c b/ssh-rand-helper.c
index 76ca3d7227257fee8c46eff01637b41778bbf4c6..0fcda7fff169f8b9ea2b0b959ab0b34158a2b776 100644 (file)
--- a/ssh-rand-helper.c
+++ b/ssh-rand-helper.c
@@ -24,6 +24,30 @@
 
 #include "includes.h"
 
+#include <sys/types.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <sys/socket.h>
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#ifdef HAVE_SYS_UN_H
+# include <sys/un.h>
+#endif
+
+#include <errno.h>
+#include <fcntl.h>
+#include <pwd.h>
+#include <signal.h>
+#include <time.h>
+#include <unistd.h>
+
 #include <openssl/rand.h>
 #include <openssl/sha.h>
 #include <openssl/crypto.h>
@@ -39,8 +63,6 @@
 #include "pathnames.h"
 #include "log.h"
 
-RCSID("$Id$");
-
 /* Number of bytes we write out */
 #define OUTPUT_SEED_SIZE       48
 
@@ -123,7 +145,7 @@ get_random_bytes_prngd(unsigned char *buf, int len,
     unsigned short tcp_port, char *socket_path)
 {
        int fd, addr_len, rval, errors;
-       char msg[2];
+       u_char msg[2];
        struct sockaddr_storage addr;
        struct sockaddr_in *addr_in = (struct sockaddr_in *)&addr;
        struct sockaddr_un *addr_un = (struct sockaddr_un *)&addr;
@@ -135,8 +157,8 @@ get_random_bytes_prngd(unsigned char *buf, int len,
        if (socket_path != NULL &&
            strlen(socket_path) >= sizeof(addr_un->sun_path))
                fatal("Random pool path is too long");
-       if (len > 255)
-               fatal("Too many bytes to read from PRNGD");
+       if (len <= 0 || len > 255)
+               fatal("Too many bytes (%d) to read from PRNGD", len);
 
        memset(&addr, '\0', sizeof(addr));
 
@@ -190,7 +212,7 @@ reopen:
                goto done;
        }
 
-       if (atomicio(read, fd, buf, len) != len) {
+       if (atomicio(read, fd, buf, len) != (size_t)len) {
                if (errno == EPIPE && errors < 10) {
                        close(fd);
                        errors++;
@@ -398,8 +420,8 @@ hash_command_output(entropy_cmd_t *src, unsigned char *hash)
        debug3("Time elapsed: %d msec", msec_elapsed);
 
        if (waitpid(pid, &status, 0) == -1) {
-              error("Couldn't wait for child '%s' completion: %s",
-                  src->cmdstring, strerror(errno));
+               error("Couldn't wait for child '%s' completion: %s",
+                   src->cmdstring, strerror(errno));
                return 0.0;
        }
 
@@ -564,7 +586,8 @@ prng_write_seedfile(void)
        /* Try to ensure that the parent directory is there */
        snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
            _PATH_SSH_USER_DIR);
-       mkdir(filename, 0700);
+       if (mkdir(filename, 0700) < 0 && errno != EEXIST)
+               fatal("mkdir %.200s: %s", filename, strerror(errno));
 
        snprintf(filename, sizeof(filename), "%.512s/%s", pw->pw_dir,
            SSH_PRNG_SEED_FILE);
@@ -600,7 +623,7 @@ prng_write_seedfile(void)
                        save_errno = errno;
                        unlink(tmpseed);
                        fatal("problem renaming PRNG seedfile from %.100s "
-                           "to %.100s (%.100s)", tmpseed, filename, 
+                           "to %.100s (%.100s)", tmpseed, filename,
                            strerror(save_errno));
                }
        }
@@ -665,8 +688,7 @@ prng_read_commands(char *cmdfilename)
        }
 
        num_cmds = 64;
-       entcmd = xmalloc(num_cmds * sizeof(entropy_cmd_t));
-       memset(entcmd, '\0', num_cmds * sizeof(entropy_cmd_t));
+       entcmd = xcalloc(num_cmds, sizeof(entropy_cmd_t));
 
        /* Read in file */
        cur_cmd = linenum = 0;
@@ -759,7 +781,7 @@ prng_read_commands(char *cmdfilename)
                 */
                if (cur_cmd == num_cmds) {
                        num_cmds *= 2;
-                       entcmd = xrealloc(entcmd, num_cmds *
+                       entcmd = xrealloc(entcmd, num_cmds,
                            sizeof(entropy_cmd_t));
                }
        }
@@ -768,12 +790,13 @@ prng_read_commands(char *cmdfilename)
        memset(&entcmd[cur_cmd], '\0', sizeof(entropy_cmd_t));
 
        /* trim to size */
-       entropy_cmds = xrealloc(entcmd, (cur_cmd + 1) *
+       entropy_cmds = xrealloc(entcmd, (cur_cmd + 1),
            sizeof(entropy_cmd_t));
 
        debug("Loaded %d entropy commands from %.100s", cur_cmd,
            cmdfilename);
 
+       fclose(f);
        return cur_cmd < MIN_ENTROPY_SOURCES ? -1 : 0;
 }
 
@@ -830,11 +853,17 @@ main(int argc, char **argv)
                default:
                        error("Invalid commandline option");
                        usage();
+                       exit(1);
                }
        }
-
        log_init(argv[0], ll, SYSLOG_FACILITY_USER, 1);
 
+       if (argc != optind) {
+               error("Unexpected commandline arguments.");
+               usage();
+               exit(1);
+       }
+
 #ifdef USE_SEED_FILES
        prng_read_seedfile();
 #endif
@@ -888,3 +917,15 @@ main(int argc, char **argv)
 
        return ret == bytes ? 0 : 1;
 }
+
+/*
+ * We may attempt to re-seed during mkstemp if we are using the one in the
+ * compat library (via mkstemp -> _gettemp -> arc4random -> seed_rng) so we
+ * need our own seed_rng().  We must also check that we have enough entropy.
+ */
+void
+seed_rng(void)
+{
+       if (!RAND_status())
+               fatal("Not enough entropy in RNG");
+}