(parse_options): New function.

(main): By default, read and hash stdin, and compare with the hash
in the signature. New option --no-data to omit this check.

Rev: src/spki/tools/spki-check-signature.c:1.3

src/spki/tools/spki-check-signature.c

@@ -23,50 +23,126 @@
 #include "certificate.h"
 #include "parse.h"
 
-#include <stdarg.h>
+#include "misc.h"
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
+#include "getopt.h"
+
 static void
-die(const char *format, ...)
+usage(void)
 {
-  va_list args;
-  va_start(args, format);
-  vfprintf(stderr, format, args);
-  va_end(args);
+  fprintf(stderr, "spki-check-signature [ --no-data ] SIGNATURE\n");
   exit(EXIT_FAILURE);
 }
 
+struct check_options
+{
+  int with_data;
+  /* NOTE: We actually use that the argv string is writable. */
+  char *signature;
+};
+
 static void
-usage(void)
+parse_options(struct check_options *o,
+	      int argc, char **argv)
 {
-  fprintf(stderr, "spki-check-signature SIGNATURE\n");
-  exit(EXIT_FAILURE);
+  o->with_data = 1;
+
+  for (;;)
+    {
+      static const struct option options[] =
+	{
+	  /* Name, args, flag, val */
+	  { "no-data", no_argument, NULL, 'n' },
+	  { "version", no_argument, NULL, 'V' },
+	  { "help", no_argument, NULL, '?' },
+	  { NULL, 0, NULL, 0 }
+	};
+      int c;
+     
+      c = getopt_long(argc, argv, "V?", options, NULL);
+    
+      switch (c)
+	{
+	default:
+	  abort();
+	
+	case -1:
+	  if (optind == argc)
+	    die("spki-check-signature: No signature given.\n");
+
+	  o->signature = argv[optind++];
+	  if (optind != argc)
+	    die("spki-check-signature: Too many arguments.\n");
+
+	  return;
+
+	case 'V':
+	  die("spki-check-signature --version not implemented\n");
+
+	case 'n':
+	  o->with_data = 0;
+	  break;
+
+	case '?':
+	  usage();
+	}
+    }
 }
 
 int
 main(int argc, char **argv)
 {
+  struct check_options o;
+  
   struct spki_acl_db db;
   struct sexp_iterator sexp;
   struct spki_iterator i;
 
   struct spki_hash_value hash;
   struct spki_principal *principal;
-  
-  if (argc != 2)
-    usage();
 
+  parse_options(&o, argc, argv);
+  
   spki_acl_init(&db);
 
-  if (sexp_transport_iterator_first(&sexp, strlen(argv[1]), argv[1])
+  if (sexp_transport_iterator_first(&sexp, strlen(o.signature), o.signature)
       && spki_iterator_first_sexp(&i, &sexp)
       && spki_check_type(&i, SPKI_TYPE_SIGNATURE)
       && spki_parse_hash(&i, &hash)
       && spki_parse_principal(&db, &i, &principal))
   {
+    if (o.with_data)
+      {
+	const struct nettle_hash *hash_algorithm;
+	uint8_t *digest;
+	
+	switch (hash.type)
+	  {
+	  default:
+	    die("Unsupported hash algorithm.");
+	  case SPKI_TYPE_MD5:
+	    hash_algorithm = &nettle_md5;
+	    break;
+	  case SPKI_TYPE_SHA1:
+	    hash_algorithm = &nettle_sha1;
+	    break;
+	  }
+
+	if (hash.length != hash_algorithm->digest_size)
+	  die("Incorrect hash (bad length)\n");
+
+	digest = hash_file(hash_algorithm, stdin);
+	if (!digest)
+	 die("Reading stdin failed.\n");
+
+	if (memcmp(digest, hash.digest, hash_algorithm->digest_size))
+	  die("Hash value doesn't match input.\n");
+      }
+    
     if (!spki_verify(NULL, &hash, principal, &i))
       die("Bad signature\n");
     if (!spki_parse_end(&i))