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                 char tmp[CAAM_ERROR_STR_MAX];
  24
  25                 dev_err(dev, "%08x: %s\n", err, caam_jr_strstatus(tmp, err));
  26         }
  27
  28         res->err = err;
  29
  30         complete(&res->completion);
  31 }
  32 EXPORT_SYMBOL(split_key_done);
  33 /*
  34 get a split ipad/opad key
  35
  36 Split key generation-----------------------------------------------
  37
  38 [00] 0xb0810008    jobdesc: stidx=1 share=never len=8
  39 [01] 0x04000014        key: class2->keyreg len=20
  40                         @0xffe01000
  41 [03] 0x84410014  operation: cls2-op sha1 hmac init dec
  42 [04] 0x24940000     fifold: class2 msgdata-last2 len=0 imm
  43 [05] 0xa4000001       jump: class2 local all ->1 [06]
  44 [06] 0x64260028    fifostr: class2 mdsplit-jdk len=40
  45                         @0xffe04000
  46 */
  47 int gen_split_key(struct device *jrdev, u8 *key_out, int split_key_len,
  48                   int split_key_pad_len, const u8 *key_in, u32 keylen,
  49                   u32 alg_op)
  50 {
  51         u32 *desc;
  52         struct split_key_result result;
  53         dma_addr_t dma_addr_in, dma_addr_out;
  54         int ret = 0;
  55
  56         desc = kmalloc(CAAM_CMD_SZ * 6 + CAAM_PTR_SZ * 2, GFP_KERNEL | GFP_DMA);
  57         if (!desc) {
  58                 dev_err(jrdev, "unable to allocate key input memory\n");
  59                 return -ENOMEM;
  60         }
  61
  62         init_job_desc(desc, 0);
  63
  64         dma_addr_in = dma_map_single(jrdev, (void *)key_in, keylen,
  65                                      DMA_TO_DEVICE);
  66         if (dma_mapping_error(jrdev, dma_addr_in)) {
  67                 dev_err(jrdev, "unable to map key input memory\n");
  68                 kfree(desc);
  69                 return -ENOMEM;
  70         }
  71         append_key(desc, dma_addr_in, keylen, CLASS_2 | KEY_DEST_CLASS_REG);
  72
  73         /* Sets MDHA up into an HMAC-INIT */
  74         append_operation(desc, alg_op | OP_ALG_DECRYPT | OP_ALG_AS_INIT);
  75
  76         /*
  77          * do a FIFO_LOAD of zero, this will trigger the internal key expansion
  78          * into both pads inside MDHA
  79          */
  80         append_fifo_load_as_imm(desc, NULL, 0, LDST_CLASS_2_CCB |
  81                                 FIFOLD_TYPE_MSG | FIFOLD_TYPE_LAST2);
  82
  83         /*
  84          * FIFO_STORE with the explicit split-key content store
  85          * (0x26 output type)
  86          */
  87         dma_addr_out = dma_map_single(jrdev, key_out, split_key_pad_len,
  88                                       DMA_FROM_DEVICE);
  89         if (dma_mapping_error(jrdev, dma_addr_out)) {
  90                 dev_err(jrdev, "unable to map key output memory\n");
  91                 kfree(desc);
  92                 return -ENOMEM;
  93         }
  94         append_fifo_store(desc, dma_addr_out, split_key_len,
  95                           LDST_CLASS_2_CCB | FIFOST_TYPE_SPLIT_KEK);
  96
  97 #ifdef DEBUG
  98         print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
  99                        DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
 100         print_hex_dump(KERN_ERR, "jobdesc@"__stringify(__LINE__)": ",
 101                        DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1);
 102 #endif
 103
 104         result.err = 0;
 105         init_completion(&result.completion);
 106
 107         ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
 108         if (!ret) {
 109                 /* in progress */
 110                 wait_for_completion_interruptible(&result.completion);
 111                 ret = result.err;
 112 #ifdef DEBUG
 113                 print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
 114                                DUMP_PREFIX_ADDRESS, 16, 4, key_out,
 115                                split_key_pad_len, 1);
 116 #endif
 117         }
 118
 119         dma_unmap_single(jrdev, dma_addr_out, split_key_pad_len,
 120                          DMA_FROM_DEVICE);
 121         dma_unmap_single(jrdev, dma_addr_in, keylen, DMA_TO_DEVICE);
 122
 123         kfree(desc);
 124
 125         return ret;
 126 }
 127 EXPORT_SYMBOL(gen_split_key);