Clean up EVP_PKEY_asn1_find_str()

Use slightly better argument and variable names, do not pointlessly try
to match a string of negative length < -1, use a size_t for the strlen()
and preserve the logic that allows lookup by a string fragment rather
than a full string.

ok jsing

diff --git a/lib/libcrypto/evp/p_lib.c b/lib/libcrypto/evp/p_lib.c
index d9cb663..fdddc49 100644 (file)
--- a/lib/libcrypto/evp/p_lib.c
+++ b/lib/libcrypto/evp/p_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: p_lib.c,v 1.55 2024/01/04 17:08:57 tb Exp $ */
+/* $OpenBSD: p_lib.c,v 1.56 2024/01/04 17:17:40 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -205,23 +205,32 @@ EVP_PKEY_asn1_find(ENGINE **engine, int pkey_id)
 }
 
 const EVP_PKEY_ASN1_METHOD *
-EVP_PKEY_asn1_find_str(ENGINE **pe, const char *str, int len)
+EVP_PKEY_asn1_find_str(ENGINE **engine, const char *str, int len)
 {
        const EVP_PKEY_ASN1_METHOD *ameth;
+       size_t str_len;
        int i;
 
+       if (engine != NULL)
+               *engine = NULL;
+
+       if (len < -1)
+               return NULL;
        if (len == -1)
-               len = strlen(str);
-       if (pe != NULL)
-               *pe = NULL;
-       for (i = EVP_PKEY_asn1_get_count() - 1; i >= 0; i--) {
-               ameth = EVP_PKEY_asn1_get0(i);
+               str_len = strlen(str);
+       else
+               str_len = len;
+
+       for (i = 0; i < N_ASN1_METHODS; i++) {
+               ameth = asn1_methods[i];
                if (ameth->pkey_flags & ASN1_PKEY_ALIAS)
                        continue;
-               if (((int)strlen(ameth->pem_str) == len) &&
-                   !strncasecmp(ameth->pem_str, str, len))
+               if (strlen(ameth->pem_str) != str_len)
+                       continue;
+               if (strncasecmp(ameth->pem_str, str, str_len) == 0)
                        return ameth;
        }
+
        return NULL;
 }