set_hex() behaviour change

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4488)

1 files changed, 11 insertions, 10 deletions

diff --git a/apps/enc.c b/apps/enc.c
index 9c85ee58b6..4b861640bf 100644
--- a/apps/enc.c
+++ b/apps/enc.c
@@ -29,7 +29,7 @@
 #define SIZE    (512)
 #define BSIZE   (8*1024)
 
-static int set_hex(char *in, unsigned char *out, int size);
+static int set_hex(const char *in, unsigned char *out, int size);
 static void show_ciphers(const OBJ_NAME *name, void *bio_);
 
 struct doall_enc_ciphers {
@@ -461,7 +461,7 @@ int enc_main(int argc, char **argv)
             int siz = EVP_CIPHER_iv_length(cipher);
             if (siz == 0) {
                 BIO_printf(bio_err, "warning: iv not use by this cipher\n");
-            } else if (!set_hex(hiv, iv, sizeof iv)) {
+            } else if (!set_hex(hiv, iv, siz)) {
                 BIO_printf(bio_err, "invalid hex iv value\n");
                 goto end;
             }
@@ -601,22 +601,23 @@ static void show_ciphers(const OBJ_NAME *name, void *arg)
         BIO_printf(dec->bio, " ");
 }
 
-static int set_hex(char *in, unsigned char *out, int size)
+static int set_hex(const char *in, unsigned char *out, int size)
 {
     int i, n;
     unsigned char j;
 
+    i = size * 2;
     n = strlen(in);
-    if (n > (size * 2)) {
-        BIO_printf(bio_err, "hex string is too long\n");
-        return 0;
+    if (n > i) {
+        BIO_printf(bio_err, "hex string is too long, ignoring excess\n");
+        n = i; /* ignore exceeding part */
+    } else if (n < i) {
+        BIO_printf(bio_err, "hex string is too short, padding with zero bytes to length\n");
     }
+
     memset(out, 0, size);
     for (i = 0; i < n; i++) {
-        j = (unsigned char)*in;
-        *(in++) = '\0';
-        if (j == 0)
-            break;
+        j = (unsigned char)*in++;
         if (!isxdigit(j)) {
             BIO_printf(bio_err, "non-hex digit\n");
             return 0;