[PATCH v2 12/28] mbedtls/external: support MicroSoft Authentication Code

Ilias Apalodimas ilias.apalodimas at linaro.org
Wed May 8 16:31:13 CEST 2024


Hi Raymond

On Tue, 7 May 2024 at 20:57, Raymond Mao <raymond.mao at linaro.org> wrote:
>
> Populate MicroSoft Authentication Code from the content data
> into PKCS7 decoding context if it exists in a PKCS7 message.
> Add OIDs for describing objects using for MicroSoft Authentication
> Code.
>

We will need more accurate commit messages for things like this.
IIRC this is already on a PR for mbedTLS and won't be needed in the
future right?
Generally speaking, we shouldn't carry out of tree patches unless we
can prove there's a very good reason. This one needs to be marked as
'do not merge' and we should wait until mbedTLS merges it upstream

Thanks
/Ilias

> Signed-off-by: Raymond Mao <raymond.mao at linaro.org>
> ---
> Changes in v2
> - None.
>
>  .../external/mbedtls/include/mbedtls/oid.h    | 30 ++++++++++
>  .../external/mbedtls/include/mbedtls/pkcs7.h  | 10 ++++
>  lib/mbedtls/external/mbedtls/library/pkcs7.c  | 60 +++++++++++++++----
>  3 files changed, 90 insertions(+), 10 deletions(-)
>
> diff --git a/lib/mbedtls/external/mbedtls/include/mbedtls/oid.h b/lib/mbedtls/external/mbedtls/include/mbedtls/oid.h
> index fdc25ebf885..2ee982808fa 100644
> --- a/lib/mbedtls/external/mbedtls/include/mbedtls/oid.h
> +++ b/lib/mbedtls/external/mbedtls/include/mbedtls/oid.h
> @@ -352,6 +352,36 @@
>  #define MBEDTLS_OID_PKCS12_PBE_SHA1_RC2_128_CBC     MBEDTLS_OID_PKCS12_PBE "\x05" /**< pbeWithSHAAnd128BitRC2-CBC OBJECT IDENTIFIER ::= {pkcs-12PbeIds 5} */
>  #define MBEDTLS_OID_PKCS12_PBE_SHA1_RC2_40_CBC      MBEDTLS_OID_PKCS12_PBE "\x06" /**< pbeWithSHAAnd40BitRC2-CBC OBJECT IDENTIFIER ::= {pkcs-12PbeIds 6} */
>
> +/*
> + * MicroSoft Authenticate Code OIDs
> + */
> +#define MBEDTLS_OID_PRIVATE_ENTERPRISE              MBEDTLS_OID_INTERNET "\x04\x01" /* {iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) */
> +#define MBEDTLS_OID_MICROSOFT                       "\x82\x37"  /* {microsoft(311)} */
> +/*
> + * OID_msIndirectData: (1.3.6.1.4.1.311.2.1.4)
> + * {iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) microsoft(311) 2(2) 1(1) 4(4)}
> + */
> +#define MBEDTLS_OID_MICROSOFT_INDIRECTDATA  MBEDTLS_OID_PRIVATE_ENTERPRISE MBEDTLS_OID_MICROSOFT \
> +    "\x02\x01\x04"
> +/*
> + * OID_msStatementType: (1.3.6.1.4.1.311.2.1.11)
> + * {iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) microsoft(311) 2(2) 1(1) 11(11)}
> + */
> +#define MBEDTLS_OID_MICROSOFT_STATETYPE  MBEDTLS_OID_PRIVATE_ENTERPRISE MBEDTLS_OID_MICROSOFT \
> +    "\x02\x01\x0b"
> +/*
> + * OID_msSpOpusInfo: (1.3.6.1.4.1.311.2.1.12)
> + * {iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) microsoft(311) 2(2) 1(1) 12(12)}
> + */
> +#define MBEDTLS_OID_MICROSOFT_SPOPUSINFO  MBEDTLS_OID_PRIVATE_ENTERPRISE MBEDTLS_OID_MICROSOFT \
> +    "\x02\x01\x0b"
> +/*
> + * OID_msPeImageDataObjId: (1.3.6.1.4.1.311.2.1.15)
> + * {iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) microsoft(311) 2(2) 1(1) 15(15)}
> + */
> +#define MBEDTLS_OID_MICROSOFT_PEIMAGEDATA  MBEDTLS_OID_PRIVATE_ENTERPRISE MBEDTLS_OID_MICROSOFT \
> +    "\x02\x01\x0f"
> +
>  /*
>   * EC key algorithms from RFC 5480
>   */
> diff --git a/lib/mbedtls/external/mbedtls/include/mbedtls/pkcs7.h b/lib/mbedtls/external/mbedtls/include/mbedtls/pkcs7.h
> index e9b482208e6..9e29b74af70 100644
> --- a/lib/mbedtls/external/mbedtls/include/mbedtls/pkcs7.h
> +++ b/lib/mbedtls/external/mbedtls/include/mbedtls/pkcs7.h
> @@ -132,12 +132,22 @@ typedef struct mbedtls_pkcs7_signed_data {
>  }
>  mbedtls_pkcs7_signed_data;
>
> +/* Content Data for MicroSoft Authentication Code using in U-Boot Secure Boot */
> +typedef struct mbedtls_pkcs7_conten_data {
> +    int data_type;  /* Type of Data */
> +    size_t data_len;    /* Length of Data */
> +    size_t data_hdrlen; /* Length of Data ASN.1 header */
> +    void *data;     /* Content Data */
> +}
> +mbedtls_pkcs7_conten_data;
> +
>  /**
>   * Structure holding PKCS #7 structure, only signed data for now
>   */
>  typedef struct mbedtls_pkcs7 {
>      mbedtls_pkcs7_buf MBEDTLS_PRIVATE(raw);
>      mbedtls_pkcs7_signed_data MBEDTLS_PRIVATE(signed_data);
> +    mbedtls_pkcs7_conten_data content_data;
>  }
>  mbedtls_pkcs7;
>
> diff --git a/lib/mbedtls/external/mbedtls/library/pkcs7.c b/lib/mbedtls/external/mbedtls/library/pkcs7.c
> index 3aac662ba69..0c2436b56b7 100644
> --- a/lib/mbedtls/external/mbedtls/library/pkcs7.c
> +++ b/lib/mbedtls/external/mbedtls/library/pkcs7.c
> @@ -29,6 +29,13 @@
>  #include <time.h>
>  #endif
>
> +enum OID {
> +    /* PKCS#7 {iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-7(7)} */
> +    MBEDTLS_OID_DATA = 13,          /* 1.2.840.113549.1.7.1 */
> +    /* Microsoft Authenticode & Software Publishing */
> +    MBEDTLS_OID_MS_INDIRECTDATA = 24,        /* 1.3.6.1.4.1.311.2.1.4 */
> +};
> +
>  /**
>   * Initializes the mbedtls_pkcs7 structure.
>   */
> @@ -449,7 +456,7 @@ cleanup:
>   *      signerInfos SignerInfos }
>   */
>  static int pkcs7_get_signed_data(unsigned char *buf, size_t buflen,
> -                                 mbedtls_pkcs7_signed_data *signed_data)
> +                                 mbedtls_pkcs7 *pkcs7)
>  {
>      unsigned char *p = buf;
>      unsigned char *end = buf + buflen;
> @@ -457,6 +464,7 @@ static int pkcs7_get_signed_data(unsigned char *buf, size_t buflen,
>      size_t len = 0;
>      int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
>      mbedtls_md_type_t md_alg;
> +    mbedtls_pkcs7_signed_data *signed_data = &pkcs7->signed_data;
>
>      ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED
>                                 | MBEDTLS_ASN1_SEQUENCE);
> @@ -493,25 +501,57 @@ static int pkcs7_get_signed_data(unsigned char *buf, size_t buflen,
>      if (ret != 0) {
>          return ret;
>      }
> -    if (MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS7_DATA, &content_type)) {
> +
> +    /*
> +     * We should only support 1.2.840.113549.1.7.1 (PKCS7 DATA) and
> +     * 1.3.6.1.4.1.311.2.1.4 (MicroSoft Authentication Code) that is for
> +     * U-Boot Secure Boot
> +     */
> +    if (!MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS7_DATA, &content_type)) {
> +        pkcs7->content_data.data_type = MBEDTLS_OID_DATA;
> +    } else if (!MBEDTLS_OID_CMP(MBEDTLS_OID_MICROSOFT_INDIRECTDATA,
> +                                &content_type)) {
> +        pkcs7->content_data.data_type = MBEDTLS_OID_MS_INDIRECTDATA;
> +    } else {
>          return MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO;
>      }
>
>      if (p != end_content_info) {
> +        unsigned char *tmp_p = p;
> +
>          /* Determine if valid content is present */
>          ret = mbedtls_asn1_get_tag(&p,
>                                     end_content_info,
>                                     &len,
> -                                   MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC);
> +                                   MBEDTLS_ASN1_CONSTRUCTED |
> +                                   MBEDTLS_ASN1_CONTEXT_SPECIFIC);
> +        if (ret != 0 || p + len != end_content_info) {
> +            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO,
> +                                     ret);
> +        }
> +
> +        /*
> +         * U-Boot Secure Boot needs to calculate the digest of MicroSoft
> +         * Authentication Code during verifying an EFI image.
> +         * Thus we need to save the context of Content Data.
> +         */
> +        pkcs7->content_data.data_hdrlen = p - tmp_p;
> +        /* Parse the content data from a sequence */
> +        ret = mbedtls_asn1_get_tag(&p, end_content_info, &len,
> +                                   MBEDTLS_ASN1_CONSTRUCTED |
> +                                   MBEDTLS_ASN1_SEQUENCE);
>          if (ret != 0) {
> -            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO, ret);
> +            /* TODO: Other Content Data formats are not supported at the moment */
> +            return MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE;
> +        } else if (p + len != end_content_info) {
> +            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO,
> +                                     ret);
>          }
> +
> +        pkcs7->content_data.data = p;
> +        pkcs7->content_data.data_len = len;
> +
>          p += len;
> -        if (p != end_content_info) {
> -            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO, ret);
> -        }
> -        /* Valid content is present - this is not supported */
> -        return MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE;
>      }
>
>      /* Look for certificates, there may or may not be any */
> @@ -624,7 +664,7 @@ int mbedtls_pkcs7_parse_der(mbedtls_pkcs7 *pkcs7, const unsigned char *buf,
>      }
>
>  try_data:
> -    ret = pkcs7_get_signed_data(p, len, &pkcs7->signed_data);
> +    ret = pkcs7_get_signed_data(p, len, pkcs7);
>      if (ret != 0) {
>          goto out;
>      }
> --
> 2.25.1
>


More information about the U-Boot mailing list