krb5/Fix-hex-conversion-of-PKINIT-certid-strings.patch

93 lines
3.0 KiB
Diff

From 8b898badbe8051270c6da96f5c15f3bc8b6d974e Mon Sep 17 00:00:00 2001
From: Sumit Bose <sbose@redhat.com>
Date: Fri, 26 Jan 2018 11:47:50 -0500
Subject: [PATCH] Fix hex conversion of PKINIT certid strings
When parsing a PKCS11 token specification, correctly convert from hex
to binary instead of using OpenSSL bignum functions (which would strip
leading zeros).
[ghudson@mit.edu: made hex_string_to_bin() a bit less verbose; wrote
commit message]
ticket: 8636
(cherry picked from commit 63e8b8142fd7b3931a7bf2d6448978ca536bafc0)
---
.../preauth/pkinit/pkinit_crypto_openssl.c | 55 +++++++++++++++----
1 file changed, 44 insertions(+), 11 deletions(-)
diff --git a/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c b/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c
index 2064eb7bd..eb2953fe1 100644
--- a/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c
+++ b/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c
@@ -4616,6 +4616,43 @@ reassemble_pkcs11_name(pkinit_identity_opts *idopts)
return ret;
}
+static int
+hex_string_to_bin(const char *str, int *bin_len_out, CK_BYTE **bin_out)
+{
+ size_t str_len, i;
+ CK_BYTE *bin;
+ char *endptr, tmp[3] = { '\0', '\0', '\0' };
+ long val;
+
+ *bin_len_out = 0;
+ *bin_out = NULL;
+
+ str_len = strlen(str);
+ if (str_len % 2 != 0)
+ return EINVAL;
+ bin = malloc(str_len / 2);
+ if (bin == NULL)
+ return ENOMEM;
+
+ errno = 0;
+ for (i = 0; i < str_len / 2; i++) {
+ tmp[0] = str[i * 2];
+ tmp[1] = str[i * 2 + 1];
+
+ val = strtol(tmp, &endptr, 16);
+ if (val < 0 || val > 255 || errno != 0 || endptr != &tmp[2]) {
+ free(bin);
+ return EINVAL;
+ }
+
+ bin[i] = (CK_BYTE)val;
+ }
+
+ *bin_len_out = str_len / 2;
+ *bin_out = bin;
+ return 0;
+}
+
static krb5_error_code
pkinit_get_certs_pkcs11(krb5_context context,
pkinit_plg_crypto_context plg_cryptoctx,
@@ -4658,18 +4695,14 @@ pkinit_get_certs_pkcs11(krb5_context context,
}
/* Convert the ascii cert_id string into a binary blob */
if (idopts->cert_id_string != NULL) {
- BIGNUM *bn = NULL;
- BN_hex2bn(&bn, idopts->cert_id_string);
- if (bn == NULL)
- return ENOMEM;
- id_cryptoctx->cert_id_len = BN_num_bytes(bn);
- id_cryptoctx->cert_id = malloc((size_t) id_cryptoctx->cert_id_len);
- if (id_cryptoctx->cert_id == NULL) {
- BN_free(bn);
- return ENOMEM;
+ r = hex_string_to_bin(idopts->cert_id_string,
+ &id_cryptoctx->cert_id_len,
+ &id_cryptoctx->cert_id);
+ if (r != 0) {
+ pkiDebug("Failed to convert certid string [%s]\n",
+ idopts->cert_id_string);
+ return r;
}
- BN_bn2bin(bn, id_cryptoctx->cert_id);
- BN_free(bn);
}
id_cryptoctx->slotid = idopts->slotid;
id_cryptoctx->pkcs11_method = 1;