Rework X509_NAME_print()

This is legacy API that we can unexport since nothing uses it directly.
Unfortunately we need to keep the functions because there are plenty of
things that use it indirectly by passing XN_FLAG_COMPAT to X509_print_ex().

The old implementation parsed the X509_NAME_oneline() output in order to
remove the / preceding the (one or two-uppercase letters) name and to
insert ", " afterward. This is just stupid in so many ways, not least
because there's basically no limit to the garbage that you can stuff into
an X.500 name.

So rework this and only include the name entries whose short names are
one or two letters long. This way, this becomes slightly saner and less
fragile.

ok jsing

1 files changed, 65 insertions, 33 deletions

diff --git a/src/lib/libcrypto/asn1/t_x509.c b/src/lib/libcrypto/asn1/t_x509.c
index 87771ab090..669aec0093 100644
--- a/src/lib/libcrypto/asn1/t_x509.c
+++ b/src/lib/libcrypto/asn1/t_x509.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: t_x509.c,v 1.47 2025/01/11 03:00:04 tb Exp $ */
+/* $OpenBSD: t_x509.c,v 1.48 2025/01/26 20:18:26 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -78,6 +78,7 @@
 #include <openssl/rsa.h>
 #endif
 
+#include "bytestring.h"
 #include "evp_local.h"
 #include "x509_local.h"
 
@@ -490,48 +491,79 @@ ASN1_UTCTIME_print(BIO *bp, const ASN1_UTCTIME *tm)
 }
 LCRYPTO_ALIAS(ASN1_UTCTIME_print);
 
-int
-X509_NAME_print(BIO *bp, const X509_NAME *name, int obase)
+/* NID with SN of 1-2 letters, which X509_NAME_print() historically included. */
+static int
+x509_name_entry_include(const X509_NAME_ENTRY *ne)
 {
-        char *s, *c, *b;
-        int i;
-        int ret = 0;
+        int nid;
 
-        b = X509_NAME_oneline(name, NULL, 0);
-        if (b == NULL)
+        if ((nid = OBJ_obj2nid(ne->object)) == NID_undef)
                 return 0;
-        if (*b == '\0') {
-                free(b);
+
+        switch (nid) {
+        case NID_commonName:
+        case NID_surname:
+        case NID_countryName:
+        case NID_localityName:
+        case NID_stateOrProvinceName:
+        case NID_organizationName:
+        case NID_organizationalUnitName:
+        case NID_givenName:
+        case NID_domainComponent: /* XXX - doesn't really belong here */
                 return 1;
         }
-        s = b + 1; /* skip the first slash */
-
-        c = s;
-        for (;;) {
-                if ((s[0] == '/' &&
-                    (s[1] >= 'A' && s[1] <= 'Z' &&
-                    (s[2] == '=' || (s[2] >= 'A' && s[2] <= 'Z' &&
-                    s[3] == '=')))) || s[0] == '\0') {
-                        i = s - c;
-                        if (BIO_write(bp, c, i) != i)
+
+        return 0;
+}
+
+int
+X509_NAME_print(BIO *bio, const X509_NAME *name, int obase)
+{
+        CBB cbb;
+        uint8_t *buf = NULL;
+        size_t buf_len;
+        const X509_NAME_ENTRY *ne;
+        int i;
+        int started = 0;
+        int ret = 0;
+
+        if (!CBB_init(&cbb, 0))
+                goto err;
+
+        for (i = 0; i < sk_X509_NAME_ENTRY_num(name->entries); i++) {
+                ne = sk_X509_NAME_ENTRY_value(name->entries, i);
+
+                if (!x509_name_entry_include(ne))
+                        continue;
+
+                if (started) {
+                        if (!CBB_add_u8(&cbb, ','))
+                                goto err;
+                        if (!CBB_add_u8(&cbb, ' '))
                                 goto err;
-                        c = s + 1;      /* skip following slash */
-                        if (*s != '\0') {
-                                if (BIO_write(bp, ", ", 2) != 2)
-                                        goto err;
-                        }
                 }
-                if (*s == '\0')
-                        break;
-                s++;
+
+                if (!X509_NAME_ENTRY_add_cbb(&cbb, ne))
+                        goto err;
+
+                started = 1;
         }
 
+        if (!CBB_finish(&cbb, &buf, &buf_len))
+                goto err;
+
+        if (buf_len > INT_MAX)
+                goto err;
+
+        if (BIO_write(bio, buf, buf_len) <= 0)
+                goto err;
+
         ret = 1;
-        if (0) {
+
  err:
-                X509error(ERR_R_BUF_LIB);
-        }
-        free(b);
-        return (ret);
+        CBB_cleanup(&cbb);
+        free(buf);
+
+        return ret;
 }
 LCRYPTO_ALIAS(X509_NAME_print);