xref: /linux/drivers/s390/crypto/zcrypt_api.h (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  *  Copyright IBM Corp. 2001, 2019
4  *  Author(s): Robert Burroughs
5  *	       Eric Rossman (edrossma@us.ibm.com)
6  *	       Cornelia Huck <cornelia.huck@de.ibm.com>
7  *
8  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
9  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
10  *				  Ralph Wuerthner <rwuerthn@de.ibm.com>
11  *  MSGTYPE restruct:		  Holger Dengler <hd@linux.vnet.ibm.com>
12  */
13 
14 #ifndef _ZCRYPT_API_H_
15 #define _ZCRYPT_API_H_
16 
17 #include <linux/atomic.h>
18 #include <asm/debug.h>
19 #include <asm/zcrypt.h>
20 #include "ap_bus.h"
21 
22 /**
23  * Supported device types
24  */
25 #define ZCRYPT_CEX2C		5
26 #define ZCRYPT_CEX2A		6
27 #define ZCRYPT_CEX3C		7
28 #define ZCRYPT_CEX3A		8
29 #define ZCRYPT_CEX4	       10
30 #define ZCRYPT_CEX5	       11
31 #define ZCRYPT_CEX6	       12
32 #define ZCRYPT_CEX7	       13
33 
34 /**
35  * Large random numbers are pulled in 4096 byte chunks from the crypto cards
36  * and stored in a page. Be careful when increasing this buffer due to size
37  * limitations for AP requests.
38  */
39 #define ZCRYPT_RNG_BUFFER_SIZE	4096
40 
41 /**
42  * The zcrypt_wait_api_operational() function waits this
43  * amount in milliseconds for ap_wait_aqpn_bindings_complete().
44  * Also on a cprb send failure with ENODEV the send functions
45  * trigger an ap bus rescan and wait this time in milliseconds
46  * for ap_wait_aqpn_bindings_complete() before resending.
47  */
48 #define ZCRYPT_WAIT_BINDINGS_COMPLETE_MS 30000
49 
50 /*
51  * Identifier for Crypto Request Performance Index
52  */
53 enum crypto_ops {
54 	MEX_1K,
55 	MEX_2K,
56 	MEX_4K,
57 	CRT_1K,
58 	CRT_2K,
59 	CRT_4K,
60 	HWRNG,
61 	SECKEY,
62 	NUM_OPS
63 };
64 
65 struct zcrypt_queue;
66 
67 /* struct to hold tracking information for a userspace request/response */
68 struct zcrypt_track {
69 	int again_counter;		/* retry attempts counter */
70 	int last_qid;			/* last qid used */
71 	int last_rc;			/* last return code */
72 };
73 
74 /* defines related to message tracking */
75 #define TRACK_AGAIN_MAX 10
76 #define TRACK_AGAIN_CARD_WEIGHT_PENALTY  1000
77 #define TRACK_AGAIN_QUEUE_WEIGHT_PENALTY 10000
78 
79 struct zcrypt_ops {
80 	long (*rsa_modexpo)(struct zcrypt_queue *, struct ica_rsa_modexpo *,
81 			    struct ap_message *);
82 	long (*rsa_modexpo_crt)(struct zcrypt_queue *,
83 				struct ica_rsa_modexpo_crt *,
84 				struct ap_message *);
85 	long (*send_cprb)(bool userspace, struct zcrypt_queue *, struct ica_xcRB *,
86 			  struct ap_message *);
87 	long (*send_ep11_cprb)(bool userspace, struct zcrypt_queue *, struct ep11_urb *,
88 			       struct ap_message *);
89 	long (*rng)(struct zcrypt_queue *, char *, struct ap_message *);
90 	struct list_head list;		/* zcrypt ops list. */
91 	struct module *owner;
92 	int variant;
93 	char name[128];
94 };
95 
96 struct zcrypt_card {
97 	struct list_head list;		/* Device list. */
98 	struct list_head zqueues;	/* List of zcrypt queues */
99 	struct kref refcount;		/* device refcounting */
100 	struct ap_card *card;		/* The "real" ap card device. */
101 	int online;			/* User online/offline */
102 
103 	int user_space_type;		/* User space device id. */
104 	char *type_string;		/* User space device name. */
105 	int min_mod_size;		/* Min number of bits. */
106 	int max_mod_size;		/* Max number of bits. */
107 	int max_exp_bit_length;
108 	const int *speed_rating;	/* Speed idx of crypto ops. */
109 	atomic_t load;			/* Utilization of the crypto device */
110 
111 	int request_count;		/* # current requests. */
112 };
113 
114 struct zcrypt_queue {
115 	struct list_head list;		/* Device list. */
116 	struct kref refcount;		/* device refcounting */
117 	struct zcrypt_card *zcard;
118 	struct zcrypt_ops *ops;		/* Crypto operations. */
119 	struct ap_queue *queue;		/* The "real" ap queue device. */
120 	int online;			/* User online/offline */
121 
122 	atomic_t load;			/* Utilization of the crypto device */
123 
124 	int request_count;		/* # current requests. */
125 
126 	struct ap_message reply;	/* Per-device reply structure. */
127 };
128 
129 /* transport layer rescanning */
130 extern atomic_t zcrypt_rescan_req;
131 
132 extern spinlock_t zcrypt_list_lock;
133 extern struct list_head zcrypt_card_list;
134 
135 #define for_each_zcrypt_card(_zc) \
136 	list_for_each_entry(_zc, &zcrypt_card_list, list)
137 
138 #define for_each_zcrypt_queue(_zq, _zc) \
139 	list_for_each_entry(_zq, &(_zc)->zqueues, list)
140 
141 struct zcrypt_card *zcrypt_card_alloc(void);
142 void zcrypt_card_free(struct zcrypt_card *);
143 void zcrypt_card_get(struct zcrypt_card *);
144 int zcrypt_card_put(struct zcrypt_card *);
145 int zcrypt_card_register(struct zcrypt_card *);
146 void zcrypt_card_unregister(struct zcrypt_card *);
147 
148 struct zcrypt_queue *zcrypt_queue_alloc(size_t);
149 void zcrypt_queue_free(struct zcrypt_queue *);
150 void zcrypt_queue_get(struct zcrypt_queue *);
151 int zcrypt_queue_put(struct zcrypt_queue *);
152 int zcrypt_queue_register(struct zcrypt_queue *);
153 void zcrypt_queue_unregister(struct zcrypt_queue *);
154 bool zcrypt_queue_force_online(struct zcrypt_queue *zq, int online);
155 
156 int zcrypt_rng_device_add(void);
157 void zcrypt_rng_device_remove(void);
158 
159 void zcrypt_msgtype_register(struct zcrypt_ops *);
160 void zcrypt_msgtype_unregister(struct zcrypt_ops *);
161 struct zcrypt_ops *zcrypt_msgtype(unsigned char *, int);
162 int zcrypt_api_init(void);
163 void zcrypt_api_exit(void);
164 long zcrypt_send_cprb(struct ica_xcRB *xcRB);
165 long zcrypt_send_ep11_cprb(struct ep11_urb *urb);
166 void zcrypt_device_status_mask_ext(struct zcrypt_device_status_ext *devstatus);
167 int zcrypt_device_status_ext(int card, int queue,
168 			     struct zcrypt_device_status_ext *devstatus);
169 
170 int zcrypt_wait_api_operational(void);
171 
172 static inline unsigned long z_copy_from_user(bool userspace,
173 					     void *to,
174 					     const void __user *from,
175 					     unsigned long n)
176 {
177 	if (likely(userspace))
178 		return copy_from_user(to, from, n);
179 	memcpy(to, (void __force *)from, n);
180 	return 0;
181 }
182 
183 static inline unsigned long z_copy_to_user(bool userspace,
184 					   void __user *to,
185 					   const void *from,
186 					   unsigned long n)
187 {
188 	if (likely(userspace))
189 		return copy_to_user(to, from, n);
190 	memcpy((void __force *)to, from, n);
191 	return 0;
192 }
193 
194 #endif /* _ZCRYPT_API_H_ */
195