Commit 5d2a6f4b authored by Patrick Steuer's avatar Patrick Steuer Committed by Andy Polyakov
Browse files

crypto/evp/e_aes.c: add comments to s390x aes gcm implementation 



Signed-off-by: default avatarPatrick Steuer <patrick.steuer@de.ibm.com>

Reviewed-by: default avatarAndy Polyakov <appro@openssl.org>
Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5230)
parent 39f5b069

crypto/evp/e_aes.c

+32 −2
Original line number Diff line number Diff line
@@ -960,8 +960,8 @@ typedef struct { 
    union {

        double align;

        /*-

         * KMA-GCM-AES parameter block

         * (see z/Architecture Principles of Operation SA22-7832-11)

         * KMA-GCM-AES parameter block - begin

         * (see z/Architecture Principles of Operation >= SA22-7832-11)

         */

        struct {

            unsigned char reserved[12];
@@ -982,6 +982,7 @@ typedef struct { 
            } j0;

            unsigned char k[32];

        } param;

        /* KMA-GCM-AES parameter block - end */

    } kma;

    unsigned int fc;

    int key_set;
@@ -1141,6 +1142,10 @@ static int s390x_aes_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, 
/* iv + padding length for iv lenghts != 12 */

# define S390X_gcm_ivpadlen(i)	((((i) + 15) >> 4 << 4) + 16)



/*-

 * Process additional authenticated data. Returns 0 on success. Code is

 * big-endian.

 */

static int s390x_aes_gcm_aad(S390X_AES_GCM_CTX *ctx, const unsigned char *aad,

                             size_t len)

{
@@ -1191,6 +1196,10 @@ static int s390x_aes_gcm_aad(S390X_AES_GCM_CTX *ctx, const unsigned char *aad, 
    return 0;

}



/*-

 * En/de-crypt plain/cipher-text and authenticate ciphertext. Returns 0 for

 * success. Code is big-endian.

 */

static int s390x_aes_gcm(S390X_AES_GCM_CTX *ctx, const unsigned char *in,

                         unsigned char *out, size_t len)

{
@@ -1276,6 +1285,9 @@ static int s390x_aes_gcm(S390X_AES_GCM_CTX *ctx, const unsigned char *in, 
    return 0;

}



/*-

 * Initialize context structure. Code is big-endian.

 */

static void s390x_aes_gcm_setiv(S390X_AES_GCM_CTX *ctx,

                                const unsigned char *iv)

{
@@ -1306,6 +1318,11 @@ static void s390x_aes_gcm_setiv(S390X_AES_GCM_CTX *ctx, 
    }

}



/*-

 * Performs various operations on the context structure depending on control

 * type. Returns 1 for success, 0 for failure and -1 for unknown control type.

 * Code is big-endian.

 */

static int s390x_aes_gcm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr)

{

    S390X_AES_GCM_CTX *gctx = EVP_C_DATA(S390X_AES_GCM_CTX, c);
@@ -1471,6 +1488,9 @@ static int s390x_aes_gcm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr) 
    }

}



/*-

 * Set key and/or iv. Returns 1 on success. Otherwise 0 is returned.

 */

static int s390x_aes_gcm_init_key(EVP_CIPHER_CTX *ctx,

                                  const unsigned char *key,

                                  const unsigned char *iv, int enc)
@@ -1510,6 +1530,10 @@ static int s390x_aes_gcm_init_key(EVP_CIPHER_CTX *ctx, 
    return 1;

}



/*-

 * En/de-crypt and authenticate TLS packet. Returns the number of bytes written

 * if successful. Otherwise -1 is returned. Code is big-endian.

 */

static int s390x_aes_gcm_tls_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

                                    const unsigned char *in, size_t len)

{
@@ -1552,6 +1576,12 @@ err: 
    return rv;

}



/*-

 * Called from EVP layer to initialize context, process additional

 * authenticated data, en/de-crypt plain/cipher-text and authenticate

 * ciphertext or process a TLS packet, depending on context. Returns bytes

 * written on success. Otherwise -1 is returned. Code is big-endian.

 */

static int s390x_aes_gcm_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

                                const unsigned char *in, size_t len)

{