-c zero: assume zero counter value.

[tfcrypt.git] / tfcrypt.c

diff --git a/tfcrypt.c b/tfcrypt.c
index c8664cca99aad14cbc4cb9e84c4bb964483f5b4a..01173fb691a214f7e666fb0f48552072b4c59756 100644 (file)
--- a/tfcrypt.c
+++ b/tfcrypt.c
@@ -91,6 +91,8 @@ _baddfname:
                                        counter_opt = TFC_CTR_HEAD;
                                else if (!strcasecmp(optarg, "rand"))
                                        counter_opt = TFC_CTR_RAND;
+                               else if (!strcasecmp(optarg, "zero"))
+                                       counter_opt = TFC_CTR_ZERO;
                                else counter_file = sksum_hashlist_file = optarg;
                                break;
                        case 'C':
@@ -920,8 +922,6 @@ _xts2genkey:        if (xwrite(krfd, pblk, TF_FROM_BITS(TFC_KEY_BITS)) == NOSIZE) xerro
        tfc_data_to_words64(&iseek_blocks, sizeof(iseek_blocks));
        tf_ctr_set(ctr, &iseek_blocks, sizeof(iseek_blocks));
 
-       if (ctr_mode == TFC_MODE_STREAM) tfe_init_iv(&tfe, key, ctr);
-
        switch (counter_opt) {
                case TFC_CTR_SHOW:
                        switch (do_outfmt) {
@@ -931,6 +931,7 @@ _xts2genkey:        if (xwrite(krfd, pblk, TF_FROM_BITS(TFC_KEY_BITS)) == NOSIZE) xerro
                        }
                        break;
                case TFC_CTR_RAND: tfc_getrandom(ctr, ctrsz); break;
+               case TFC_CTR_ZERO: memset(ctr, 0, ctrsz); break;
        }
 
 _ctrskip2:
@@ -1003,6 +1004,8 @@ _ctrwagain:       lio = xwrite(dfd, pblk, lrem);
                delta_processed += ldone;
        }
 
+       if (ctr_mode == TFC_MODE_STREAM) tfe_init_iv(&tfe, key, ctr);
+
        errno = 0;
        do_stop = NO;
        while (1) {