Remove custom PKCS7 ASN1 functions, add new structs

crypto/CMakeLists.txt

@@ -461,6 +461,7 @@ add_library(
   pem/pem_x509.c
   pem/pem_xaux.c
   pkcs7/pkcs7.c
+  pkcs7/pkcs7_asn1.c
   pkcs7/pkcs7_x509.c
   pkcs8/pkcs8.c
   pkcs8/pkcs8_x509.c

crypto/pkcs7/internal.h

@@ -22,6 +22,155 @@ extern "C" {
 #endif
 
 
+typedef struct pkcs7_issuer_and_serial_st PKCS7_ISSUER_AND_SERIAL;
+typedef struct pkcs7_enc_content_st PKCS7_ENC_CONTENT;
+
+DECLARE_ASN1_FUNCTIONS(PKCS7_ISSUER_AND_SERIAL)
+DECLARE_ASN1_FUNCTIONS(PKCS7_SIGNED)
+DECLARE_ASN1_FUNCTIONS(PKCS7_ENC_CONTENT)
+DECLARE_ASN1_FUNCTIONS(PKCS7_ENCRYPT)
+DECLARE_ASN1_FUNCTIONS(PKCS7_ENVELOPE)
+DECLARE_ASN1_FUNCTIONS(PKCS7_DIGEST)
+DECLARE_ASN1_FUNCTIONS(PKCS7_SIGN_ENVELOPE)
+
+DEFINE_STACK_OF(PKCS7)
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-11.1
+//
+//   SignedAndEnvelopedData ::= SEQUENCE {
+//     version Version,
+//     recipientInfos RecipientInfos,
+//     digestAlgorithms DigestAlgorithmIdentifiers,
+//     encryptedContentInfo EncryptedContentInfo,
+//     certificates
+//        [0] IMPLICIT ExtendedCertificatesAndCertificates
+//          OPTIONAL,
+//     crls
+//       [1] IMPLICIT CertificateRevocationLists OPTIONAL,
+//     signerInfos SignerInfos }
+struct pkcs7_sign_envelope_st {
+    ASN1_INTEGER *version;
+    STACK_OF(PKCS7_RECIP_INFO) *recipientinfo;
+    STACK_OF(X509_ALGOR) *md_algs;
+    PKCS7_ENC_CONTENT *enc_data;
+    STACK_OF(X509) *cert;
+    STACK_OF(X509_CRL) *crl;
+    STACK_OF(PKCS7_SIGNER_INFO) *signer_info;
+};
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-6.7
+//
+//   IssuerAndSerialNumber ::= SEQUENCE {
+//     issuer Name,
+//     serialNumber CertificateSerialNumber }
+struct pkcs7_issuer_and_serial_st {
+    X509_NAME *issuer;
+    ASN1_INTEGER *serial;
+};
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-9.2
+//
+//   SignerInfo ::= SEQUENCE {
+//     version Version,
+//     issuerAndSerialNumber IssuerAndSerialNumber,
+//     digestAlgorithm DigestAlgorithmIdentifier,
+//     authenticatedAttributes
+//       [0] IMPLICIT Attributes OPTIONAL,
+//     digestEncryptionAlgorithm
+//       DigestEncryptionAlgorithmIdentifier,
+//     encryptedDigest EncryptedDigest,
+//     unauthenticatedAttributes
+//       [1] IMPLICIT Attributes OPTIONAL }
+//
+//   EncryptedDigest ::= OCTET STRING
+struct pkcs7_signer_info_st {
+    ASN1_INTEGER *version;
+    PKCS7_ISSUER_AND_SERIAL *issuer_and_serial;
+    X509_ALGOR *digest_alg;
+    STACK_OF(X509_ATTRIBUTE) *auth_attr;
+    X509_ALGOR *digest_enc_alg;
+    ASN1_OCTET_STRING *enc_digest;
+    STACK_OF(X509_ATTRIBUTE) *unauth_attr;
+    EVP_PKEY *pkey; // NOTE: |pkey| is not seriliazed.
+};
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-10.2
+//
+//   RecipientInfo ::= SEQUENCE {
+//     version Version,
+//     issuerAndSerialNumber IssuerAndSerialNumber,
+//     keyEncryptionAlgorithm
+//
+//       KeyEncryptionAlgorithmIdentifier,
+//     encryptedKey EncryptedKey }
+//
+//   EncryptedKey ::= OCTET STRING
+struct pkcs7_recip_info_st {
+    ASN1_INTEGER *version;
+    PKCS7_ISSUER_AND_SERIAL *issuer_and_serial;
+    X509_ALGOR *key_enc_algor;
+    ASN1_OCTET_STRING *enc_key;
+    X509 *cert; // NOTE: |cert| is not serialized
+};
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-10.1
+//
+//   EncryptedContentInfo ::= SEQUENCE {
+//     contentType ContentType,
+//     contentEncryptionAlgorithm
+//       ContentEncryptionAlgorithmIdentifier,
+//     encryptedContent
+//       [0] IMPLICIT EncryptedContent OPTIONAL }
+//
+//   EncryptedContent ::= OCTET STRING
+struct pkcs7_enc_content_st {
+    ASN1_OBJECT *content_type;
+    X509_ALGOR *algorithm;
+    ASN1_OCTET_STRING *enc_data;
+    const EVP_CIPHER *cipher;   // NOTE: |cipher| is not serialized
+};
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-10.1
+//
+//    EnvelopedData ::= SEQUENCE {
+//      version Version,
+//      recipientInfos RecipientInfos,
+//      encryptedContentInfo EncryptedContentInfo }
+//
+//    RecipientInfos ::= SET OF RecipientInfo
+struct pkcs7_envelope_st {
+  ASN1_INTEGER *version;
+  PKCS7_ENC_CONTENT *enc_data;
+  STACK_OF(PKCS7_RECIP_INFO) *recipientinfo;
+};
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-12
+//
+//   DigestedData ::= SEQUENCE {
+//     version Version,
+//     digestAlgorithm DigestAlgorithmIdentifier,
+//     contentInfo ContentInfo,
+//     digest Digest }
+//
+//   Digest ::= OCTET STRING
+struct pkcs7_digest_st {
+    ASN1_INTEGER *version;
+    X509_ALGOR *digest_alg;
+    PKCS7 *contents;
+    ASN1_OCTET_STRING *digest;
+    const EVP_MD *md;   // NOTE: |md| is not serialized
+};
+
+// ASN.1 defined here https://datatracker.ietf.org/doc/html/rfc2315#section-13
+//
+//   EncryptedData ::= SEQUENCE {
+//     version Version,
+//     encryptedContentInfo EncryptedContentInfo }
+struct pkcs7_encrypt_st {
+    ASN1_INTEGER *version;
+    PKCS7_ENC_CONTENT *enc_data;
+};
+
 // pkcs7_parse_header reads the non-certificate/non-CRL prefix of a PKCS#7
 // SignedData blob from |cbs| and sets |*out| to point to the rest of the
 // input. If the input is in BER format, then |*der_bytes| will be set to a

crypto/pkcs7/pkcs7_asn1.c

@@ -0,0 +1,189 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0 OR ISC
+
+#include <openssl/pkcs7.h>
+
+#include <openssl/asn1t.h>
+#include <openssl/pem.h>
+
+#include "internal.h"
+#include "../internal.h"
+#include "../bytestring/internal.h"
+
+ASN1_ADB_TEMPLATE(p7default) = ASN1_EXP_OPT(PKCS7, d.other, ASN1_ANY, 0);
+
+ASN1_ADB(PKCS7) = {
+        ADB_ENTRY(NID_pkcs7_data, ASN1_EXP_OPT(PKCS7, d.data, ASN1_OCTET_STRING, 0)),
+        ADB_ENTRY(NID_pkcs7_signed, ASN1_EXP_OPT(PKCS7, d.sign, PKCS7_SIGNED, 0)),
+        ADB_ENTRY(NID_pkcs7_enveloped, ASN1_EXP_OPT(PKCS7, d.enveloped, PKCS7_ENVELOPE, 0)),
+        ADB_ENTRY(NID_pkcs7_signedAndEnveloped, ASN1_EXP_OPT(PKCS7, d.signed_and_enveloped, PKCS7_SIGN_ENVELOPE, 0)),
+        ADB_ENTRY(NID_pkcs7_digest, ASN1_EXP_OPT(PKCS7, d.digest, PKCS7_DIGEST, 0)),
+        ADB_ENTRY(NID_pkcs7_encrypted, ASN1_EXP_OPT(PKCS7, d.encrypted, PKCS7_ENCRYPT, 0))
+} ASN1_ADB_END(PKCS7, 0, type, 0, &p7default_tt, NULL);
+
+ASN1_SEQUENCE(PKCS7) = {
+    ASN1_SIMPLE(PKCS7, type, ASN1_OBJECT),
+    ASN1_ADB_OBJECT(PKCS7)
+} ASN1_SEQUENCE_END(PKCS7)
+
+IMPLEMENT_ASN1_ALLOC_FUNCTIONS(PKCS7)
+
+PKCS7 *d2i_PKCS7(PKCS7 **a, const unsigned char **in, long len) {
+  uint8_t *der_bytes = NULL;
+  PKCS7 *ret = NULL;
+  CBS cbs, cbs_der;
+
+  if (!in) {
+    return NULL;
+  }
+
+  CBS_init(&cbs, *in, len);
+  // |CBS_asn1_ber_to_der| will allocate memory and point |der_bytes| to it.
+  // we're responsible for freeing this below.
+  if (!CBS_asn1_ber_to_der(&cbs, &cbs_der, &der_bytes)) {
+      goto err;
+  }
+
+  // |CBS_asn1_ber_to_der| will set |der_bytes| to NULL if it doesn't detect
+  // any convertible BER elements in |in|.
+  if (der_bytes == NULL) {
+    ret = (PKCS7 *) ASN1_item_d2i(
+        (ASN1_VALUE **) a, in, len,
+        ASN1_ITEM_rptr(PKCS7)
+    );
+  } else {
+    // |ASN1_item_d2i| will increment the input pointer by |der_len| length, so
+    // save off another pointer so we can free |der_bytes| at the end of this
+    // function.
+    uint8_t *der_bytes_ptr = der_bytes;
+    size_t der_len = CBS_len(&cbs_der);
+    ret = (PKCS7 *) ASN1_item_d2i(
+        (ASN1_VALUE **) a, (const uint8_t**) &der_bytes_ptr,
+        der_len, ASN1_ITEM_rptr(PKCS7)
+    );
+    // Advance |*in| by however many bytes |ASN1_item_d2i| advanced
+    // |der_bytes_ptr|
+    *in += der_bytes_ptr - der_bytes;
+  }
+
+err:
+  OPENSSL_free(der_bytes);
+  der_bytes = NULL;
+  return ret;
+}
+
+int i2d_PKCS7(PKCS7 *a, unsigned char **out) {
+    return ASN1_item_i2d((ASN1_VALUE *)a, out, ASN1_ITEM_rptr(PKCS7));
+}
+
+IMPLEMENT_ASN1_DUP_FUNCTION(PKCS7)
+
+ASN1_SEQUENCE(PKCS7_SIGNED) = {
+        ASN1_SIMPLE(PKCS7_SIGNED, version, ASN1_INTEGER),
+        ASN1_SET_OF(PKCS7_SIGNED, md_algs, X509_ALGOR),
+        ASN1_SIMPLE(PKCS7_SIGNED, contents, PKCS7),
+        ASN1_IMP_SEQUENCE_OF_OPT(PKCS7_SIGNED, cert, X509, 0),
+        ASN1_IMP_SET_OF_OPT(PKCS7_SIGNED, crl, X509_CRL, 1),
+        ASN1_SET_OF(PKCS7_SIGNED, signer_info, PKCS7_SIGNER_INFO)
+} ASN1_SEQUENCE_END(PKCS7_SIGNED)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_SIGNED)
+
+ASN1_SEQUENCE(PKCS7_ISSUER_AND_SERIAL) = {
+        ASN1_SIMPLE(PKCS7_ISSUER_AND_SERIAL, issuer, X509_NAME),
+        ASN1_SIMPLE(PKCS7_ISSUER_AND_SERIAL, serial, ASN1_INTEGER)
+} ASN1_SEQUENCE_END(PKCS7_ISSUER_AND_SERIAL)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_ISSUER_AND_SERIAL)
+
+// Minor tweak to operation: free up X509.
+static int recip_info_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
+                 void *exarg)
+{
+    if (operation == ASN1_OP_FREE_POST) {
+        PKCS7_RECIP_INFO *ri = (PKCS7_RECIP_INFO *)*pval;
+        X509_free(ri->cert);
+    }
+    return 1;
+}
+
+ASN1_SEQUENCE_cb(PKCS7_RECIP_INFO, recip_info_cb) = {
+        ASN1_SIMPLE(PKCS7_RECIP_INFO, version, ASN1_INTEGER),
+        ASN1_SIMPLE(PKCS7_RECIP_INFO, issuer_and_serial, PKCS7_ISSUER_AND_SERIAL),
+        ASN1_SIMPLE(PKCS7_RECIP_INFO, key_enc_algor, X509_ALGOR),
+        ASN1_SIMPLE(PKCS7_RECIP_INFO, enc_key, ASN1_OCTET_STRING)
+} ASN1_SEQUENCE_END_cb(PKCS7_RECIP_INFO, PKCS7_RECIP_INFO)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_RECIP_INFO)
+
+// Minor tweak to operation: free up EVP_PKEY.
+static int signer_info_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
+                 void *exarg)
+{
+    PKCS7_SIGNER_INFO *si = (PKCS7_SIGNER_INFO *)*pval;
+    if (operation == ASN1_OP_FREE_POST) {
+        EVP_PKEY_free(si->pkey);
+    }
+    return 1;
+}
+
+ASN1_SEQUENCE_cb(PKCS7_SIGNER_INFO, signer_info_cb) = {
+        ASN1_SIMPLE(PKCS7_SIGNER_INFO, version, ASN1_INTEGER),
+        ASN1_SIMPLE(PKCS7_SIGNER_INFO, issuer_and_serial, PKCS7_ISSUER_AND_SERIAL),
+        ASN1_SIMPLE(PKCS7_SIGNER_INFO, digest_alg, X509_ALGOR),
+        /* NB this should be a SET OF but we use a SEQUENCE OF so the
+         * original order * is retained when the structure is reencoded.
+         * Since the attributes are implicitly tagged this will not affect
+         * the encoding.
+         */
+        ASN1_IMP_SEQUENCE_OF_OPT(PKCS7_SIGNER_INFO, auth_attr, X509_ATTRIBUTE, 0),
+        ASN1_SIMPLE(PKCS7_SIGNER_INFO, digest_enc_alg, X509_ALGOR),
+        ASN1_SIMPLE(PKCS7_SIGNER_INFO, enc_digest, ASN1_OCTET_STRING),
+        ASN1_IMP_SET_OF_OPT(PKCS7_SIGNER_INFO, unauth_attr, X509_ATTRIBUTE, 1)
+} ASN1_SEQUENCE_END_cb(PKCS7_SIGNER_INFO, PKCS7_SIGNER_INFO)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_SIGNER_INFO)
+
+ASN1_SEQUENCE(PKCS7_ENC_CONTENT) = {
+        ASN1_SIMPLE(PKCS7_ENC_CONTENT, content_type, ASN1_OBJECT),
+        ASN1_SIMPLE(PKCS7_ENC_CONTENT, algorithm, X509_ALGOR),
+        ASN1_IMP_OPT(PKCS7_ENC_CONTENT, enc_data, ASN1_OCTET_STRING, 0)
+} ASN1_SEQUENCE_END(PKCS7_ENC_CONTENT)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_ENC_CONTENT)
+
+ASN1_SEQUENCE(PKCS7_SIGN_ENVELOPE) = {
+        ASN1_SIMPLE(PKCS7_SIGN_ENVELOPE, version, ASN1_INTEGER),
+        ASN1_SET_OF(PKCS7_SIGN_ENVELOPE, recipientinfo, PKCS7_RECIP_INFO),
+        ASN1_SET_OF(PKCS7_SIGN_ENVELOPE, md_algs, X509_ALGOR),
+        ASN1_SIMPLE(PKCS7_SIGN_ENVELOPE, enc_data, PKCS7_ENC_CONTENT),
+        ASN1_IMP_SET_OF_OPT(PKCS7_SIGN_ENVELOPE, cert, X509, 0),
+        ASN1_IMP_SET_OF_OPT(PKCS7_SIGN_ENVELOPE, crl, X509_CRL, 1),
+        ASN1_SET_OF(PKCS7_SIGN_ENVELOPE, signer_info, PKCS7_SIGNER_INFO)
+} ASN1_SEQUENCE_END(PKCS7_SIGN_ENVELOPE)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_SIGN_ENVELOPE)
+
+ASN1_SEQUENCE(PKCS7_ENCRYPT) = {
+        ASN1_SIMPLE(PKCS7_ENCRYPT, version, ASN1_INTEGER),
+        ASN1_SIMPLE(PKCS7_ENCRYPT, enc_data, PKCS7_ENC_CONTENT)
+} ASN1_SEQUENCE_END(PKCS7_ENCRYPT)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_ENCRYPT)
+
+ASN1_SEQUENCE(PKCS7_DIGEST) = {
+        ASN1_SIMPLE(PKCS7_DIGEST, version, ASN1_INTEGER),
+        ASN1_SIMPLE(PKCS7_DIGEST, md, X509_ALGOR),
+        ASN1_SIMPLE(PKCS7_DIGEST, contents, PKCS7),
+        ASN1_SIMPLE(PKCS7_DIGEST, digest, ASN1_OCTET_STRING)
+} ASN1_SEQUENCE_END(PKCS7_DIGEST)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_DIGEST)
+
+ASN1_SEQUENCE(PKCS7_ENVELOPE) = {
+        ASN1_SIMPLE(PKCS7_ENVELOPE, version, ASN1_INTEGER),
+        ASN1_SET_OF(PKCS7_ENVELOPE, recipientinfo, PKCS7_RECIP_INFO),
+        ASN1_SIMPLE(PKCS7_ENVELOPE, enc_data, PKCS7_ENC_CONTENT)
+} ASN1_SEQUENCE_END(PKCS7_ENVELOPE)
+
+IMPLEMENT_ASN1_FUNCTIONS(PKCS7_ENVELOPE)