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