get_random_data() can return NULL (for instance, if we can't open /dev/random

[u/mdw/putty] / cmdgen.c

diff --git a/cmdgen.c b/cmdgen.c
index dfca9dc..9aa585f 100644 (file)
--- a/cmdgen.c
+++ b/cmdgen.c
@@ -640,6 +640,11 @@ int main(int argc, char **argv)
 
        random_ref();
        entropy = get_random_data(bits / 8);
+       if (!entropy) {
+           fprintf(stderr, "puttygen: failed to collect entropy, "
+                   "could not generate key\n");
+           return 1;
+       }
        random_add_heavynoise(entropy, bits / 8);
        memset(entropy, 0, bits/8);
        sfree(entropy);
@@ -893,7 +898,7 @@ int main(int argc, char **argv)
            assert(ssh1key);
 
            if (outfile)
-               fp = f_open(outfilename, "w");
+               fp = f_open(outfilename, "w", FALSE);
            else
                fp = stdout;
            dec1 = bignum_decimal(ssh1key->exponent);
@@ -951,7 +956,7 @@ int main(int argc, char **argv)
                *p++ = '\0';
 
            if (outfile)
-               fp = f_open(outfilename, "w");
+               fp = f_open(outfilename, "w", FALSE);
            else
                fp = stdout;
            fprintf(fp, "%s\n", buffer);
@@ -981,7 +986,7 @@ int main(int argc, char **argv)
            }
 
            if (outfile)
-               fp = f_open(outfilename, "w");
+               fp = f_open(outfilename, "w", FALSE);
            else
                fp = stdout;
            fprintf(fp, "%s\n", fingerprint);