From: Andrey Rys <rys@lynxlynx.ru>
Date: Fri, 22 Mar 2019 09:44:19 +0000 (+0700)
Subject: -c zero: assume zero counter value.
X-Git-Url: https://jxself.org/git/?p=tfcrypt.git;a=commitdiff_plain;h=0b911d4a813fe164d62ef6ef132c5a4f9a441d57

-c zero: assume zero counter value.
---

diff --git a/VERSION b/VERSION
index 3c03207..d6b2404 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-18
+19
diff --git a/tfc_error.c b/tfc_error.c
index 001273e..b90b108 100644
--- a/tfc_error.c
+++ b/tfc_error.c
@@ -171,6 +171,7 @@ void usage(void)
 	tfc_say("    show: do default action, then dump CTR value to stderr,");
 	tfc_say("    head: when decrypting, read CTR from beginning of stream,");
 	tfc_say("    rand: generate random CTR and write it to beginning of stream,");
+	tfc_say("    zero: assume zero CTR is used, do not read from and write it to stream,");
 	tfc_say("    <file>: read CTR from given file (both when encrypting/decrypting).");
 	tfc_say("      default is to derive CTR from user provided password or keyfile with");
 	tfc_say("      a single Skein function turn over derived, %u byte raw key", TFC_U(TF_KEY_SIZE));
diff --git a/tfcrypt.c b/tfcrypt.c
index 8d01618..01173fb 100644
--- 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':
@@ -929,6 +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:
diff --git a/tfcrypt.h b/tfcrypt.h
index 649fc06..c41f38d 100644
--- a/tfcrypt.h
+++ b/tfcrypt.h
@@ -226,6 +226,6 @@ enum {
 	TFC_MODE_SKSUM = -2, TFC_MODE_PLAIN = -1, TFC_MODE_CTR = 1,
 	TFC_MODE_STREAM, TFC_MODE_XTS, TFC_MODE_ECB, TFC_MODE_CBC, TFC_MODE_OCB
 };
-enum { TFC_CTR_SHOW = 1, TFC_CTR_HEAD, TFC_CTR_RAND };
+enum { TFC_CTR_SHOW = 1, TFC_CTR_HEAD, TFC_CTR_RAND, TFC_CTR_ZERO };
 
 #endif