- (djm) ssh-rand-helper improvements

   - Add commandline debugging options
   - Don't write binary data if stdout is a tty (use hex instead)
   - Give it a manpage

1 files changed, 69 insertions, 13 deletions

diff --git a/ssh-rand-helper.c b/ssh-rand-helper.c
index 07856e5c3..8f2283ead 100644
--- a/ssh-rand-helper.c
+++ b/ssh-rand-helper.c
@@ -39,7 +39,7 @@
 #include "pathnames.h"
 #include "log.h"
 
-RCSID("$Id: ssh-rand-helper.c,v 1.5 2002/02/10 07:32:30 djm Exp $");
+RCSID("$Id: ssh-rand-helper.c,v 1.6 2002/04/14 09:27:13 djm Exp $");
 
 /* Number of bytes we write out */
 #define OUTPUT_SEED_SIZE        48
@@ -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;
 }