1 
2 /*
3  * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
4  *
5  * Licensed under the Apache License 2.0 (the "License").  You may not use
6  * this file except in compliance with the License.  You can obtain a copy
7  * in the file LICENSE in the source distribution or at
8  * https://www.openssl.org/source/license.html
9  */
10 
11 #include <openssl/aes.h>
12 #include "ciphercommon_aead.h"
13 
14 typedef struct prov_gcm_hw_st PROV_GCM_HW;
15 
16 #define GCM_IV_DEFAULT_SIZE 12 /* IV's for AES_GCM should normally be 12 bytes */
17 #define GCM_IV_MAX_SIZE     (1024 / 8)
18 #define GCM_TAG_MAX_SIZE    16
19 
20 #if defined(OPENSSL_CPUID_OBJ) && defined(__s390__)
21 /*-
22  * KMA-GCM-AES parameter block - begin
23  * (see z/Architecture Principles of Operation >= SA22-7832-11)
24  */
25 typedef struct S390X_kma_params_st {
26     unsigned char reserved[12];
27     union {
28         unsigned int w;
29         unsigned char b[4];
30     } cv; /* 32 bit counter value */
31     union {
32         unsigned long long g[2];
33         unsigned char b[16];
34     } t; /* tag */
35     unsigned char h[16]; /* hash subkey */
36     unsigned long long taadl; /* total AAD length */
37     unsigned long long tpcl; /* total plaintxt/ciphertxt len */
38     union {
39         unsigned long long g[2];
40         unsigned int w[4];
41     } j0;                   /* initial counter value */
42     unsigned char k[32];    /* key */
43 } S390X_KMA_PARAMS;
44 
45 #endif
46 
47 typedef struct prov_gcm_ctx_st {
48     unsigned int mode;          /* The mode that we are using */
49     size_t keylen;
50     size_t ivlen;
51     size_t taglen;
52     size_t tls_aad_pad_sz;
53     size_t tls_aad_len;         /* TLS AAD length */
54     uint64_t tls_enc_records;   /* Number of TLS records encrypted */
55 
56     /*
57      * num contains the number of bytes of |iv| which are valid for modes that
58      * manage partial blocks themselves.
59      */
60     size_t num;
61     size_t bufsz;               /* Number of bytes in buf */
62     uint64_t flags;
63 
64     unsigned int iv_state;      /* set to one of IV_STATE_XXX */
65     unsigned int enc:1;         /* Set to 1 if we are encrypting or 0 otherwise */
66     unsigned int pad:1;         /* Whether padding should be used or not */
67     unsigned int key_set:1;     /* Set if key initialised */
68     unsigned int iv_gen_rand:1; /* No IV was specified, so generate a rand IV */
69     unsigned int iv_gen:1;      /* It is OK to generate IVs */
70 
71     unsigned char iv[GCM_IV_MAX_SIZE]; /* Buffer to use for IV's */
72     unsigned char buf[AES_BLOCK_SIZE]; /* Buffer of partial blocks processed via update calls */
73 
74     OSSL_LIB_CTX *libctx;    /* needed for rand calls */
75     const PROV_GCM_HW *hw;  /* hardware specific methods */
76     GCM128_CONTEXT gcm;
77     ctr128_f ctr;
78     const void *ks;
79 } PROV_GCM_CTX;
80 
81 PROV_CIPHER_FUNC(int, GCM_setkey, (PROV_GCM_CTX *ctx, const unsigned char *key,
82                                    size_t keylen));
83 PROV_CIPHER_FUNC(int, GCM_setiv, (PROV_GCM_CTX *dat, const unsigned char *iv,
84                                   size_t ivlen));
85 PROV_CIPHER_FUNC(int, GCM_aadupdate, (PROV_GCM_CTX *ctx,
86                                       const unsigned char *aad, size_t aadlen));
87 PROV_CIPHER_FUNC(int, GCM_cipherupdate, (PROV_GCM_CTX *ctx,
88                                          const unsigned char *in, size_t len,
89                                          unsigned char *out));
90 PROV_CIPHER_FUNC(int, GCM_cipherfinal, (PROV_GCM_CTX *ctx, unsigned char *tag));
91 PROV_CIPHER_FUNC(int, GCM_oneshot, (PROV_GCM_CTX *ctx, unsigned char *aad,
92                                     size_t aad_len, const unsigned char *in,
93                                     size_t in_len, unsigned char *out,
94                                     unsigned char *tag, size_t taglen));
95 struct prov_gcm_hw_st {
96   OSSL_GCM_setkey_fn setkey;
97   OSSL_GCM_setiv_fn setiv;
98   OSSL_GCM_aadupdate_fn aadupdate;
99   OSSL_GCM_cipherupdate_fn cipherupdate;
100   OSSL_GCM_cipherfinal_fn cipherfinal;
101   OSSL_GCM_oneshot_fn oneshot;
102 };
103 
104 OSSL_FUNC_cipher_encrypt_init_fn ossl_gcm_einit;
105 OSSL_FUNC_cipher_decrypt_init_fn ossl_gcm_dinit;
106 OSSL_FUNC_cipher_get_ctx_params_fn ossl_gcm_get_ctx_params;
107 OSSL_FUNC_cipher_set_ctx_params_fn ossl_gcm_set_ctx_params;
108 OSSL_FUNC_cipher_cipher_fn ossl_gcm_cipher;
109 OSSL_FUNC_cipher_update_fn ossl_gcm_stream_update;
110 OSSL_FUNC_cipher_final_fn ossl_gcm_stream_final;
111 void ossl_gcm_initctx(void *provctx, PROV_GCM_CTX *ctx, size_t keybits,
112                       const PROV_GCM_HW *hw);
113 
114 int ossl_gcm_setiv(PROV_GCM_CTX *ctx, const unsigned char *iv, size_t ivlen);
115 int ossl_gcm_aad_update(PROV_GCM_CTX *ctx, const unsigned char *aad,
116                         size_t aad_len);
117 int ossl_gcm_cipher_final(PROV_GCM_CTX *ctx, unsigned char *tag);
118 int ossl_gcm_one_shot(PROV_GCM_CTX *ctx, unsigned char *aad, size_t aad_len,
119                       const unsigned char *in, size_t in_len,
120                       unsigned char *out, unsigned char *tag, size_t tag_len);
121 int ossl_gcm_cipher_update(PROV_GCM_CTX *ctx, const unsigned char *in,
122                            size_t len, unsigned char *out);
123 
124 #define GCM_HW_SET_KEY_CTR_FN(ks, fn_set_enc_key, fn_block, fn_ctr)            \
125     ctx->ks = ks;                                                              \
126     fn_set_enc_key(key, keylen * 8, ks);                                       \
127     CRYPTO_gcm128_init(&ctx->gcm, ks, (block128_f)fn_block);                   \
128     ctx->ctr = (ctr128_f)fn_ctr;                                               \
129     ctx->key_set = 1;
130