From db1ae1ea01bac132e8ac7992e62935e811a6eb69 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?=
 <manuel.pegourie-gonnard@arm.com>
Date: Wed, 24 Feb 2016 14:36:05 +0000
Subject: [PATCH] x509:

-
---
 include/mbedtls/x509_csr.h | 6 ++++++
 library/x509_csr.c         | 8 +++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/include/mbedtls/x509_csr.h b/include/mbedtls/x509_csr.h
index 34998a3a5..7a9c2e055 100644
--- a/include/mbedtls/x509_csr.h
+++ b/include/mbedtls/x509_csr.h
@@ -83,6 +83,8 @@ mbedtls_x509write_csr;
 /**
  * \brief          Load a Certificate Signing Request (CSR) in DER format
  *
+ * \note           CSR attributes (if any) are currently silently ignored.
+ *
  * \param csr      CSR context to fill
  * \param buf      buffer holding the CRL data
  * \param buflen   size of the buffer
@@ -95,6 +97,8 @@ int mbedtls_x509_csr_parse_der( mbedtls_x509_csr *csr,
 /**
  * \brief          Load a Certificate Signing Request (CSR), DER or PEM format
  *
+ * \note           See notes for \c mbedtls_x509_csr_parse_der()
+ *
  * \param csr      CSR context to fill
  * \param buf      buffer holding the CRL data
  * \param buflen   size of the buffer
@@ -108,6 +112,8 @@ int mbedtls_x509_csr_parse( mbedtls_x509_csr *csr, const unsigned char *buf, siz
 /**
  * \brief          Load a Certificate Signing Request (CSR)
  *
+ * \note           See notes for \c mbedtls_x509_csr_parse()
+ *
  * \param csr      CSR context to fill
  * \param path     filename to read the CSR from
  *
diff --git a/library/x509_csr.c b/library/x509_csr.c
index dbf659b44..f8c45f8d2 100644
--- a/library/x509_csr.c
+++ b/library/x509_csr.c
@@ -207,6 +207,13 @@ int mbedtls_x509_csr_parse_der( mbedtls_x509_csr *csr,
 
     /*
      *  attributes    [0] Attributes
+     *
+     *  The list of possible attributes is open-ended, though RFC 2985
+     *  (PKCS#9) defines a few in section 5.4. We currently don't support any,
+     *  so we just ignore them. This is a safe thing to do as the worst thing
+     *  that could happen is that we issue a certificate that does not match
+     *  the requester's expectations - this cannot cause a violation of our
+     *  signature policies.
      */
     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
             MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC ) ) != 0 )
@@ -214,7 +221,6 @@ int mbedtls_x509_csr_parse_der( mbedtls_x509_csr *csr,
         mbedtls_x509_csr_free( csr );
         return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
     }
-    // TODO Parse Attributes / extension requests
 
     p += len;