Avoid using i2d_RSAPublicKey()

This should help with future portability efforts, and perhaps
makes the code a bit more readable.

OK tb@

diff --git a/usr.sbin/rpki-client/print.c b/usr.sbin/rpki-client/print.c
index 9395cd0..3649c6b 100644 (file)
--- a/usr.sbin/rpki-client/print.c
+++ b/usr.sbin/rpki-client/print.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: print.c,v 1.46 2024/02/01 15:11:38 tb Exp $ */
+/*     $OpenBSD: print.c,v 1.47 2024/02/13 20:36:42 job Exp $ */
 /*
  * Copyright (c) 2021 Claudio Jeker <claudio@openbsd.org>
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -83,27 +83,26 @@ void
 tal_print(const struct tal *p)
 {
        char                    *ski;
-       EVP_PKEY                *pk;
-       RSA                     *r;
-       const unsigned char     *der;
-       unsigned char           *rder = NULL;
+       const unsigned char     *der, *pkey_der;
+       X509_PUBKEY             *pubkey;
+       ASN1_OBJECT             *obj;
        unsigned char            md[SHA_DIGEST_LENGTH];
-       int                      rder_len;
+       int                      nid, der_len;
        size_t                   i;
 
-       der = p->pkey;
-       pk = d2i_PUBKEY(NULL, &der, p->pkeysz);
-       if (pk == NULL)
-               errx(1, "d2i_PUBKEY failed in %s", __func__);
+       pkey_der = p->pkey;
+       if ((pubkey = d2i_X509_PUBKEY(NULL, &pkey_der, p->pkeysz)) == NULL)
+               errx(1, "d2i_X509_PUBKEY failed");
 
-       r = EVP_PKEY_get0_RSA(pk);
-       if (r == NULL)
-               errx(1, "EVP_PKEY_get0_RSA failed in %s", __func__);
-       if ((rder_len = i2d_RSAPublicKey(r, &rder)) <= 0)
-               errx(1, "i2d_RSAPublicKey failed in %s", __func__);
+       if (!X509_PUBKEY_get0_param(&obj, &der, &der_len, NULL, pubkey))
+               errx(1, "X509_PUBKEY_get0_param failed");
 
-       if (!EVP_Digest(rder, rder_len, md, NULL, EVP_sha1(), NULL))
-               errx(1, "EVP_Digest failed in %s", __func__);
+       if ((nid = OBJ_obj2nid(obj)) != NID_rsaEncryption)
+               errx(1, "RFC 7935: wrong signature algorithm %s, want %s",
+                   nid2str(nid), LN_rsaEncryption);
+
+       if (!EVP_Digest(der, der_len, md, NULL, EVP_sha1(), NULL))
+               errx(1, "EVP_Digest failed");
 
        ski = hex_encode(md, SHA_DIGEST_LENGTH);
 
@@ -126,8 +125,7 @@ tal_print(const struct tal *p)
                }
        }
 
-       EVP_PKEY_free(pk);
-       free(rder);
+       X509_PUBKEY_free(pubkey);
        free(ski);
 }