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