drivers/crypto/caam/key_gen.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * CAAM/SEC 4.x functions for handling key-generation jobs
   4  *
   5  * Copyright 2008-2011 Freescale Semiconductor, Inc.
   6  *
   7  */
   8 #include "compat.h"
   9 #include "jr.h"
  10 #include "error.h"
  11 #include "desc_constr.h"
  12 #include "key_gen.h"
  13
  14 void split_key_done(struct device *dev, u32 *desc, u32 err,
  15                            void *context)
  16 {
  17         struct split_key_result *res = context;
  18
  19 #ifdef DEBUG
  20         dev_err(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err);
  21 #endif
  22
  23         if (err)
  24                 caam_jr_strstatus(dev, err);
  25
  26         res->err = err;
  27
  28         complete(&res->completion);
  29 }
  30 EXPORT_SYMBOL(split_key_done);
  31 /*
  32 get a split ipad/opad key
  33
  34 Split key generation-----------------------------------------------
  35
  36 [00] 0xb0810008    jobdesc: stidx=1 share=never len=8
  37 [01] 0x04000014        key: class2->keyreg len=20
  38                         @0xffe01000
  39 [03] 0x84410014  operation: cls2-op sha1 hmac init dec
  40 [04] 0x24940000     fifold: class2 msgdata-last2 len=0 imm
  41 [05] 0xa4000001       jump: class2 local all ->1 [06]
  42 [06] 0x64260028    fifostr: class2 mdsplit-jdk len=40
  43                         @0xffe04000
  44 */
  45 int gen_split_key(struct device *jrdev, u8 *key_out,
  46                   struct alginfo * const adata, const u8 *key_in, u32 keylen,
  47                   int max_keylen)
  48 {
  49         u32 *desc;
  50         struct split_key_result result;
  51         dma_addr_t dma_addr;
  52         int ret = -ENOMEM;
  53
  54         adata->keylen = split_key_len(adata->algtype & OP_ALG_ALGSEL_MASK);
  55         adata->keylen_pad = split_key_pad_len(adata->algtype &
  56                                               OP_ALG_ALGSEL_MASK);
  57
  58 #ifdef DEBUG
  59         dev_err(jrdev, "split keylen %d split keylen padded %d\n",
  60                 adata->keylen, adata->keylen_pad);
  61         print_hex_dump(KERN_ERR, "ctx.key@" __stringify(__LINE__)": ",
  62                        DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
  63 #endif
  64
  65         if (adata->keylen_pad > max_keylen)
  66                 return -EINVAL;
  67
  68         desc = kmalloc(CAAM_CMD_SZ * 6 + CAAM_PTR_SZ * 2, GFP_KERNEL | GFP_DMA);
  69         if (!desc) {
  70                 dev_err(jrdev, "unable to allocate key input memory\n");
  71                 return ret;
  72         }
  73
  74         memcpy(key_out, key_in, keylen);
  75
  76         dma_addr = dma_map_single(jrdev, key_out, adata->keylen_pad,
  77                                   DMA_BIDIRECTIONAL);
  78         if (dma_mapping_error(jrdev, dma_addr)) {
  79                 dev_err(jrdev, "unable to map key memory\n");
  80                 goto out_free;
  81         }
  82
  83         init_job_desc(desc, 0);
  84         append_key(desc, dma_addr, keylen, CLASS_2 | KEY_DEST_CLASS_REG);
  85
  86         /* Sets MDHA up into an HMAC-INIT */
  87         append_operation(desc, (adata->algtype & OP_ALG_ALGSEL_MASK) |
  88                          OP_ALG_AAI_HMAC | OP_TYPE_CLASS2_ALG | OP_ALG_DECRYPT |
  89                          OP_ALG_AS_INIT);
  90
  91         /*
  92          * do a FIFO_LOAD of zero, this will trigger the internal key expansion
  93          * into both pads inside MDHA
  94          */
  95         append_fifo_load_as_imm(desc, NULL, 0, LDST_CLASS_2_CCB |
  96                                 FIFOLD_TYPE_MSG | FIFOLD_TYPE_LAST2);
  97
  98         /*
  99          * FIFO_STORE with the explicit split-key content store
 100          * (0x26 output type)
 101          */
 102         append_fifo_store(desc, dma_addr, adata->keylen,
 103                           LDST_CLASS_2_CCB | FIFOST_TYPE_SPLIT_KEK);
 104
 105 #ifdef DEBUG
 106         print_hex_dump(KERN_ERR, "jobdesc@"__stringify(__LINE__)": ",
 107                        DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1);
 108 #endif
 109
 110         result.err = 0;
 111         init_completion(&result.completion);
 112
 113         ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
 114         if (!ret) {
 115                 /* in progress */
 116                 wait_for_completion(&result.completion);
 117                 ret = result.err;
 118 #ifdef DEBUG
 119                 print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
 120                                DUMP_PREFIX_ADDRESS, 16, 4, key_out,
 121                                adata->keylen_pad, 1);
 122 #endif
 123         }
 124
 125         dma_unmap_single(jrdev, dma_addr, adata->keylen_pad, DMA_BIDIRECTIONAL);
 126 out_free:
 127         kfree(desc);
 128         return ret;
 129 }
 130 EXPORT_SYMBOL(gen_split_key);