drivers/crypto/caam/key_gen.c

   1 /*
   2  * CAAM/SEC 4.x functions for handling key-generation jobs
   3  *
   4  * Copyright 2008-2011 Freescale Semiconductor, Inc.
   5  *
   6  */
   7 #include "compat.h"
   8 #include "jr.h"
   9 #include "error.h"
  10 #include "desc_constr.h"
  11 #include "key_gen.h"
  12
  13 void split_key_done(struct device *dev, u32 *desc, u32 err,
  14                            void *context)
  15 {
  16         struct split_key_result *res = context;
  17
  18 #ifdef DEBUG
  19         dev_err(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err);
  20 #endif
  21
  22         if (err)
  23                 caam_jr_strstatus(dev, err);
  24
  25         res->err = err;
  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, int split_key_len,
  45                   int split_key_pad_len, const u8 *key_in, u32 keylen,
  46                   u32 alg_op)
  47 {
  48         u32 *desc;
  49         struct split_key_result result;
  50         dma_addr_t dma_addr_in, dma_addr_out;
  51         int ret = -ENOMEM;
  52
  53         desc = kmalloc(CAAM_CMD_SZ * 6 + CAAM_PTR_SZ * 2, GFP_KERNEL | GFP_DMA);
  54         if (!desc) {
  55                 dev_err(jrdev, "unable to allocate key input memory\n");
  56                 return ret;
  57         }
  58
  59         dma_addr_in = dma_map_single(jrdev, (void *)key_in, keylen,
  60                                      DMA_TO_DEVICE);
  61         if (dma_mapping_error(jrdev, dma_addr_in)) {
  62                 dev_err(jrdev, "unable to map key input memory\n");
  63                 goto out_free;
  64         }
  65
  66         dma_addr_out = dma_map_single(jrdev, key_out, split_key_pad_len,
  67                                       DMA_FROM_DEVICE);
  68         if (dma_mapping_error(jrdev, dma_addr_out)) {
  69                 dev_err(jrdev, "unable to map key output memory\n");
  70                 goto out_unmap_in;
  71         }
  72
  73         init_job_desc(desc, 0);
  74         append_key(desc, dma_addr_in, keylen, CLASS_2 | KEY_DEST_CLASS_REG);
  75
  76         /* Sets MDHA up into an HMAC-INIT */
  77         append_operation(desc, alg_op | OP_ALG_DECRYPT | OP_ALG_AS_INIT);
  78
  79         /*
  80          * do a FIFO_LOAD of zero, this will trigger the internal key expansion
  81          * into both pads inside MDHA
  82          */
  83         append_fifo_load_as_imm(desc, NULL, 0, LDST_CLASS_2_CCB |
  84                                 FIFOLD_TYPE_MSG | FIFOLD_TYPE_LAST2);
  85
  86         /*
  87          * FIFO_STORE with the explicit split-key content store
  88          * (0x26 output type)
  89          */
  90         append_fifo_store(desc, dma_addr_out, split_key_len,
  91                           LDST_CLASS_2_CCB | FIFOST_TYPE_SPLIT_KEK);
  92
  93 #ifdef DEBUG
  94         print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
  95                        DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
  96         print_hex_dump(KERN_ERR, "jobdesc@"__stringify(__LINE__)": ",
  97                        DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1);
  98 #endif
  99
 100         result.err = 0;
 101         init_completion(&result.completion);
 102
 103         ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
 104         if (!ret) {
 105                 /* in progress */
 106                 wait_for_completion_interruptible(&result.completion);
 107                 ret = result.err;
 108 #ifdef DEBUG
 109                 print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
 110                                DUMP_PREFIX_ADDRESS, 16, 4, key_out,
 111                                split_key_pad_len, 1);
 112 #endif
 113         }
 114
 115         dma_unmap_single(jrdev, dma_addr_out, split_key_pad_len,
 116                          DMA_FROM_DEVICE);
 117 out_unmap_in:
 118         dma_unmap_single(jrdev, dma_addr_in, keylen, DMA_TO_DEVICE);
 119 out_free:
 120         kfree(desc);
 121         return ret;
 122 }
 123 EXPORT_SYMBOL(gen_split_key);