X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/e19fadd7784a90d2bfe73c6b69e4a31ee785b953..dee42491003c8fdd01bd039da46b9d6a2d171584:/sshpubk.c

diff --git a/sshpubk.c b/sshpubk.c
index f87a0814..166afbcb 100644
--- a/sshpubk.c
+++ b/sshpubk.c
@@ -79,8 +79,8 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only,
     i += 4;
 
     /* Now the serious stuff. An ordinary SSH 1 public key. */
-    i += makekey(buf + i, key, NULL, 1);
-    if (len - i < 0)
+    i += makekey(buf + i, len, key, NULL, 1);
+    if (i < 0)
 	goto end;		       /* overran */
 
     if (pub_only) {
@@ -138,18 +138,18 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only,
      * decryption exponent, and then the three auxiliary values
      * (iqmp, q, p).
      */
-    i += makeprivate(buf + i, key);
-    if (len - i < 0)
-	goto end;
-    i += ssh1_read_bignum(buf + i, &key->iqmp);
-    if (len - i < 0)
-	goto end;
-    i += ssh1_read_bignum(buf + i, &key->q);
-    if (len - i < 0)
-	goto end;
-    i += ssh1_read_bignum(buf + i, &key->p);
-    if (len - i < 0)
-	goto end;
+    j = makeprivate(buf + i, len - i, key);
+    if (j < 0) goto end;
+    i += j;
+    j = ssh1_read_bignum(buf + i, len - i, &key->iqmp);
+    if (j < 0) goto end;
+    i += j;
+    j = ssh1_read_bignum(buf + i, len - i, &key->q);
+    if (j < 0) goto end;
+    i += j;
+    j = ssh1_read_bignum(buf + i, len - i, &key->p);
+    if (j < 0) goto end;
+    i += j;
 
     if (!rsa_verify(key)) {
 	*error = "rsa_verify failed";
@@ -186,6 +186,7 @@ int loadrsakey(const Filename *filename, struct RSAKey *key, char *passphrase,
 	 * This routine will take care of calling fclose() for us.
 	 */
 	ret = loadrsakey_main(fp, key, FALSE, NULL, passphrase, &error);
+	fp = NULL;
 	goto end;
     }
 
@@ -195,7 +196,8 @@ int loadrsakey(const Filename *filename, struct RSAKey *key, char *passphrase,
     error = "not an SSH-1 RSA file";
 
   end:
-    fclose(fp);
+    if (fp)
+	fclose(fp);
     if ((ret != 1) && errorstr)
 	*errorstr = error;
     return ret;
@@ -264,6 +266,7 @@ int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen,
 	    *blob = rsa_public_blob(&key, bloblen);
 	    freersakey(&key);
 	    ret = 1;
+	    fp = NULL;
 	}
     } else {
 	error = "not an SSH-1 RSA file";
@@ -373,7 +376,8 @@ int saversakey(const Filename *filename, struct RSAKey *key, char *passphrase)
     fp = f_open(*filename, "wb");
     if (fp) {
 	int ret = (fwrite(buf, 1, p - buf, fp) == (size_t) (p - buf));
-	ret = ret && (fclose(fp) == 0);
+        if (fclose(fp))
+            ret = 0;
 	return ret;
     } else
 	return 0;
@@ -457,10 +461,9 @@ int saversakey(const Filename *filename, struct RSAKey *key, char *passphrase)
  * with "PuTTY-User-Key-File-1" (version number differs). In this
  * format the Private-MAC: field only covers the private-plaintext
  * field and nothing else (and without the 4-byte string length on
- * the front too). Moreover, for RSA keys the Private-MAC: field
- * can be replaced with a Private-Hash: field which is a plain
- * SHA-1 hash instead of an HMAC. This is not allowable in DSA
- * keys. (Yes, the old format was a mess. Guess why it changed :-)
+ * the front too). Moreover, the Private-MAC: field can be replaced
+ * with a Private-Hash: field which is a plain SHA-1 hash instead of
+ * an HMAC (this was generated for unencrypted keys).
  */
 
 static int read_header(FILE * fp, char *header)
@@ -612,6 +615,16 @@ struct ssh2_userkey ssh2_wrong_passphrase = {
     NULL, NULL, NULL
 };
 
+const struct ssh_signkey *find_pubkey_alg(const char *name)
+{
+    if (!strcmp(name, "ssh-rsa"))
+	return &ssh_rsa;
+    else if (!strcmp(name, "ssh-dss"))
+	return &ssh_dss;
+    else
+	return NULL;
+}
+
 struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
 				       char *passphrase, const char **errorstr)
 {
@@ -653,11 +666,8 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
     if ((b = read_body(fp)) == NULL)
 	goto error;
     /* Select key algorithm structure. */
-    if (!strcmp(b, "ssh-rsa"))
-	alg = &ssh_rsa;
-    else if (!strcmp(b, "ssh-dss"))
-	alg = &ssh_dss;
-    else {
+    alg = find_pubkey_alg(b);
+    if (!alg) {
 	sfree(b);
 	goto error;
     }
@@ -712,8 +722,7 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
 	if ((mac = read_body(fp)) == NULL)
 	    goto error;
 	is_mac = 1;
-    } else if (0 == strcmp(header, "Private-Hash") &&
-			   alg == &ssh_rsa && old_fmt) {
+    } else if (0 == strcmp(header, "Private-Hash") && old_fmt) {
 	if ((mac = read_body(fp)) == NULL)
 	    goto error;
 	is_mac = 0;
@@ -814,6 +823,7 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
 	    /* An incorrect MAC is an unconditional Error if the key is
 	     * unencrypted. Otherwise, it means Wrong Passphrase. */
 	    if (cipher) {
+		error = "wrong passphrase";
 		ret = SSH2_WRONG_PASSPHRASE;
 	    } else {
 		error = "MAC failed";
@@ -897,11 +907,8 @@ char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm,
     if ((b = read_body(fp)) == NULL)
 	goto error;
     /* Select key algorithm structure. Currently only ssh-rsa. */
-    if (!strcmp(b, "ssh-rsa"))
-	alg = &ssh_rsa;
-    else if (!strcmp(b, "ssh-dss"))
-	alg = &ssh_dss;
-    else {
+    alg = find_pubkey_alg(b);
+    if (!alg) {
 	sfree(b);
 	goto error;
     }