- (djm) ssh-rand-helper improvements

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

diff --git a/ssh-rand-helper.c b/ssh-rand-helper.c
index 28ea6591251e4a66017c16402b5d0627911d8a28..72a818f91f03be42f814809216c178fd14003ce6 100644 (file)
--- a/ssh-rand-helper.c
+++ b/ssh-rand-helper.c
@@ -747,38 +747,88 @@ prng_read_commands(char *cmdfilename)
        return cur_cmd < MIN_ENTROPY_SOURCES ? -1 : 0;
 }
 
+void
+usage(void)
+{
+       fprintf(stderr, "Usage: %s [options]\n", __progname);
+       fprintf(stderr, "  -v          Verbose; display verbose debugging messages.\n");
+       fprintf(stderr, "              Multiple -v increases verbosity.\n");
+       fprintf(stderr, "  -x          Force output in hexidecimal (for debugging)\n");
+       fprintf(stderr, "  -X          Force output in binary\n");
+       fprintf(stderr, "  -b bytes    Number of bytes to output (default %d)\n",
+           OUTPUT_SEED_SIZE);
+}
+
 int 
 main(int argc, char **argv)
 {
-       unsigned char buf[OUTPUT_SEED_SIZE];
-       int ret;
+       unsigned char *buf;
+       int ret, ch, debug_level, output_hex, bytes;
+       extern char *optarg;
+       LogLevel ll;
 
        __progname = get_progname(argv[0]);
-       /* XXX: need some debugging mode */
        log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
 
+       ll = SYSLOG_LEVEL_INFO;
+       debug_level = output_hex = 0;
+       bytes = OUTPUT_SEED_SIZE;
+
+       /* Don't write binary data to a tty, unless we are forced to */
+       if (isatty(STDOUT_FILENO))
+               output_hex = 1;
+       
+       while ((ch = getopt(argc, argv, "vxXhb:")) != -1) {
+               switch (ch) {
+               case 'v':
+                       if (debug_level < 3)
+                               ll = SYSLOG_LEVEL_DEBUG1 + debug_level++;
+                       break;
+               case 'x':
+                       output_hex = 1;
+                       break;
+               case 'X':
+                       output_hex = 0;
+                       break;
+               case 'b':
+                       if ((bytes = atoi(optarg)) <= 0)
+                               fatal("Invalid number of output bytes");
+                       break;
+               case 'h':
+                       usage();
+                       exit(0);
+               default:
+                       error("Invalid commandline option");
+                       usage();
+               }
+       }
+
+       log_init(argv[0], ll, SYSLOG_FACILITY_USER, 1);
+       
 #ifdef USE_SEED_FILES
        prng_read_seedfile();
 #endif
 
+       buf = xmalloc(bytes);
+
        /*
         * Seed the RNG from wherever we can
         */
         
        /* Take whatever is on the stack, but don't credit it */
-       RAND_add(buf, sizeof(buf), 0);
+       RAND_add(buf, bytes, 0);
 
        debug("Seeded RNG with %i bytes from system calls", 
            (int)stir_from_system());
 
 #ifdef PRNGD_PORT
-       if (get_random_bytes_prngd(buf, sizeof(buf), PRNGD_PORT, NULL) == -1)
+       if (get_random_bytes_prngd(buf, bytes, PRNGD_PORT, NULL) == -1)
                fatal("Entropy collection failed");
-       RAND_add(buf, sizeof(buf), sizeof(buf));
+       RAND_add(buf, bytes, bytes);
 #elif defined(PRNGD_SOCKET)
-       if (get_random_bytes_prngd(buf, sizeof(buf), 0, PRNGD_SOCKET) == -1)
+       if (get_random_bytes_prngd(buf, bytes, 0, PRNGD_SOCKET) == -1)
                fatal("Entropy collection failed");
-       RAND_add(buf, sizeof(buf), sizeof(buf));
+       RAND_add(buf, bytes, bytes);
 #else
        /* Read in collection commands */
        if (prng_read_commands(SSH_PRNG_COMMAND_FILE) == -1)
@@ -798,12 +848,18 @@ main(int argc, char **argv)
        if (!RAND_status())
                fatal("Not enough entropy in RNG");
 
-       RAND_bytes(buf, sizeof(buf));
+       RAND_bytes(buf, bytes);
 
-       ret = atomicio(write, STDOUT_FILENO, buf, sizeof(buf));
+       if (output_hex) {
+               for(ret = 0; ret < bytes; ret++)
+                       printf("%02x", (unsigned char)(buf[ret]));
+               printf("\n");
+       } else
+               ret = atomicio(write, STDOUT_FILENO, buf, bytes);
                
-       memset(buf, '\0', sizeof(buf));
+       memset(buf, '\0', bytes);
+       xfree(buf);
        
-       return ret == sizeof(buf) ? 0 : 1;
+       return ret == bytes ? 0 : 1;
 }