REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2539

Microsoft signtool supports creation of attached P7's with any OID payload
via the "/p7co" parameter. It is necessary to check the data before get
the string.

Signed-off-by: GuoMinJ <newexplorerj@gmail.com>
---
 .../BaseCryptLib/Pk/CryptPkcs7VerifyBase.c    | 51 ++++++++++++++++++-
 1 file changed, 50 insertions(+), 1 deletion(-)

diff --git a/CryptoPkg/Library/BaseCryptLib/Pk/CryptPkcs7VerifyBase.c b/CryptoPkg/Library/BaseCryptLib/Pk/CryptPkcs7VerifyBase.c
index 313f459b11..d437e52e1f 100644
--- a/CryptoPkg/Library/BaseCryptLib/Pk/CryptPkcs7VerifyBase.c
+++ b/CryptoPkg/Library/BaseCryptLib/Pk/CryptPkcs7VerifyBase.c
@@ -13,6 +13,53 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <openssl/x509v3.h>
 #include <openssl/pkcs7.h>
 
+/**
+  Check the contents of PKCS7 is not data.
+
+  @param p7   Pointer to the location which the PKCS7 is located at.
+
+  @return int The content type.
+**/
+static int PKCS7_type_is_other(PKCS7 *p7)
+{
+    int isOther = 1;
+
+    int nid = OBJ_obj2nid(p7->type);
+
+    switch (nid) {
+    case NID_pkcs7_data:
+    case NID_pkcs7_signed:
+    case NID_pkcs7_enveloped:
+    case NID_pkcs7_signedAndEnveloped:
+    case NID_pkcs7_digest:
+    case NID_pkcs7_encrypted:
+        isOther = 0;
+        break;
+    default:
+        isOther = 1;
+    }
+
+    return isOther;
+
+}
+
+/**
+  Get the ASN.1 string for the PKCS7.
+
+  @param p7   Pointer to the location which the PKCS7 is located at.
+
+  @return ASN1_OCTET_STRING  ASN.1 string.
+**/
+static ASN1_OCTET_STRING *PKCS7_get_octet_string(PKCS7 *p7)
+{
+    if (PKCS7_type_is_data(p7))
+        return p7->d.data;
+    if (PKCS7_type_is_other(p7) && p7->d.other
+        && (p7->d.other->type == V_ASN1_OCTET_STRING))
+        return p7->d.other->value.octet_string;
+    return NULL;
+}
+
 /**
   Extracts the attached content from a PKCS#7 signed data if existed. The input signed
   data could be wrapped in a ContentInfo structure.
@@ -98,7 +145,9 @@ Pkcs7GetAttachedContent (
     //
     // Retrieve the attached content in PKCS7 signedData
     //
-    OctStr = Pkcs7->d.sign->contents->d.data;
+    OctStr = PKCS7_get_octet_string(Pkcs7->d.sign->contents);
+    DEBUG ((DEBUG_INFO, "OctStr->Type:     %x\n", OctStr->type));
+    DEBUG ((DEBUG_INFO, "OctStr->Length:   %x\n", OctStr->length));
     if ((OctStr->length > 0) && (OctStr->data != NULL)) {
       *ContentSize = OctStr->length;
       *Content     = AllocatePool (*ContentSize);
-- 
2.17.1


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