pkcs11-tool.c - fixup

Error in printing ec point caused segfault

 On branch X25519-improvements-2
 Changes to be committed:
	modified:   tools/pkcs11-tool.c

Author: dengert

src/tools/pkcs11-tool.c

@@ -5621,27 +5621,36 @@ show_key(CK_SESSION_HANDLE sess, CK_OBJECT_HANDLE obj)
 		}
 		if (pub) {
 			unsigned char *bytes = NULL;
+			unsigned char *body;
+
 			unsigned long ksize = 0;
 			unsigned int n;
 			unsigned long body_len = 0;
 
-			bytes = getEC_POINT(sess, obj, &ksize);
+			bytes = getEC_POINT(sess, obj, &size);
 			/*
 			 * simple parse of DER BIT STRING 0x03 or OCTET STRING 0x04
 			 * good to 65K bytes
 			 */
-			if (ksize > 3 && (bytes[0] == 0x03 || bytes[0] == 0x04)) {
-				if (bytes[1] <= 127 && ksize == (unsigned long)(bytes[1] + 2)) {
-					body_len = ksize - 2;
+			if (size > 3 && (bytes[0] == 0x03 || bytes[0] == 0x04)) {
+				if (bytes[1] <= 127 && size == (unsigned long)(bytes[1] + 2)) {
+					body_len = size - 2;
+					body = bytes + 2;
 				} else if (bytes[1] == 0x81 && size == ((unsigned long)bytes[2] + 3)) {
-					body_len = ksize - 3;
+					body_len = size - 3;
+					body = bytes + 3;
 				} else if (bytes[1] == 0x82 && size == ((unsigned long)(bytes[2] << 8) + (unsigned long)bytes[3] + 4)) {
-					body_len = ksize - 4;
+					body_len = size - 4;
+					body = bytes + 4;
+				} else {
+					body_len = 0; /* some problem with size */
 				}
 			}
 			/* With BIT STRING remove unused bits in last byte indicator */
-			if (body_len > 0 && bytes[0] == 0x03)
+			if (body_len > 0 && bytes[0] == 0x03) {
 				body_len--;
+				body++;
+			}
 
 			if (key_type == CKK_EC && body_len > 0) {
 				/*
@@ -5653,32 +5662,34 @@ show_key(CK_SESSION_HANDLE sess, CK_OBJECT_HANDLE obj)
 				 * Do simple size calculation based on DER encoding
 				 */
 				ksize = (body_len - 1) * 4;
+
 			} else if (body_len > 0) {
 				/*
 				 * EDDSA and XEDDSA in PKCS11 and only one coordinate
 				 */
-				 /* TODO rebase on changes in master in this area */
-				ksize = (body_len) * 8 - 1;
-				size = body_len;
+				ksize = (body_len) * 8;
+				if (ksize == 256)
+					ksize--; /* as 25519 uses 255 as bits */
 			}
 
 			if (ksize)
 				printf("  EC_POINT %lu bits\n", ksize);
 			else
 				printf("  EC_POINT size unknown");
 
-			if (bytes) {
+			if (bytes && body) {
 				if ((CK_LONG)size > 0) { /* Will print the point here */
 					printf("  EC_POINT:   ");
-					for (n = 0; n < size; n++)
-						printf("%02x", bytes[n]);
+					for (n = 0; n < body_len; n++)
+						printf("%02x", body[n]);
 					printf("\n");
 				}
-				free(bytes);
 			}
+			free(bytes);
 			bytes = NULL;
+			size = 0;
 			bytes = getEC_PARAMS(sess, obj, &size);
-			if (bytes){
+			if (bytes) {
 				if ((CK_LONG)size > 0) {
 					struct sc_object_id oid;