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 /**
  15  * split_key_len - Compute MDHA split key length for a given algorithm
  16  * @hash: Hashing algorithm selection, one of OP_ALG_ALGSEL_* - MD5, SHA1,
  17  *        SHA224, SHA384, SHA512.
  18  *
  19  * Return: MDHA split key length
  20  */
  21 static inline u32 split_key_len(u32 hash)
  22 {
  23         /* Sizes for MDHA pads (*not* keys): MD5, SHA1, 224, 256, 384, 512 */
  24         static const u8 mdpadlen[] = { 16, 20, 32, 32, 64, 64 };
  25         u32 idx;
  26
  27         idx = (hash & OP_ALG_ALGSEL_SUBMASK) >> OP_ALG_ALGSEL_SHIFT;
  28
  29         return (u32)(mdpadlen[idx] * 2);
  30 }
  31
  32 /**
  33  * split_key_pad_len - Compute MDHA split key pad length for a given algorithm
  34  * @hash: Hashing algorithm selection, one of OP_ALG_ALGSEL_* - MD5, SHA1,
  35  *        SHA224, SHA384, SHA512.
  36  *
  37  * Return: MDHA split key pad length
  38  */
  39 static inline u32 split_key_pad_len(u32 hash)
  40 {
  41         return ALIGN(split_key_len(hash), 16);
  42 }
  43
  44 void split_key_done(struct device *dev, u32 *desc, u32 err,
  45                            void *context)
  46 {
  47         struct split_key_result *res = context;
  48
  49 #ifdef DEBUG
  50         dev_err(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err);
  51 #endif
  52
  53         if (err)
  54                 caam_jr_strstatus(dev, err);
  55
  56         res->err = err;
  57
  58         complete(&res->completion);
  59 }
  60 EXPORT_SYMBOL(split_key_done);
  61 /*
  62 get a split ipad/opad key
  63
  64 Split key generation-----------------------------------------------
  65
  66 [00] 0xb0810008    jobdesc: stidx=1 share=never len=8
  67 [01] 0x04000014        key: class2->keyreg len=20
  68                         @0xffe01000
  69 [03] 0x84410014  operation: cls2-op sha1 hmac init dec
  70 [04] 0x24940000     fifold: class2 msgdata-last2 len=0 imm
  71 [05] 0xa4000001       jump: class2 local all ->1 [06]
  72 [06] 0x64260028    fifostr: class2 mdsplit-jdk len=40
  73                         @0xffe04000
  74 */
  75 int gen_split_key(struct device *jrdev, u8 *key_out,
  76                   struct alginfo * const adata, const u8 *key_in, u32 keylen,
  77                   int max_keylen)
  78 {
  79         u32 *desc;
  80         struct split_key_result result;
  81         dma_addr_t dma_addr_in, dma_addr_out;
  82         int ret = -ENOMEM;
  83
  84         adata->keylen = split_key_len(adata->algtype & OP_ALG_ALGSEL_MASK);
  85         adata->keylen_pad = split_key_pad_len(adata->algtype &
  86                                               OP_ALG_ALGSEL_MASK);
  87
  88 #ifdef DEBUG
  89         dev_err(jrdev, "split keylen %d split keylen padded %d\n",
  90                 adata->keylen, adata->keylen_pad);
  91         print_hex_dump(KERN_ERR, "ctx.key@" __stringify(__LINE__)": ",
  92                        DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
  93 #endif
  94
  95         if (adata->keylen_pad > max_keylen)
  96                 return -EINVAL;
  97
  98         desc = kmalloc(CAAM_CMD_SZ * 6 + CAAM_PTR_SZ * 2, GFP_KERNEL | GFP_DMA);
  99         if (!desc) {
 100                 dev_err(jrdev, "unable to allocate key input memory\n");
 101                 return ret;
 102         }
 103
 104         dma_addr_in = dma_map_single(jrdev, (void *)key_in, keylen,
 105                                      DMA_TO_DEVICE);
 106         if (dma_mapping_error(jrdev, dma_addr_in)) {
 107                 dev_err(jrdev, "unable to map key input memory\n");
 108                 goto out_free;
 109         }
 110
 111         dma_addr_out = dma_map_single(jrdev, key_out, adata->keylen_pad,
 112                                       DMA_FROM_DEVICE);
 113         if (dma_mapping_error(jrdev, dma_addr_out)) {
 114                 dev_err(jrdev, "unable to map key output memory\n");
 115                 goto out_unmap_in;
 116         }
 117
 118         init_job_desc(desc, 0);
 119         append_key(desc, dma_addr_in, keylen, CLASS_2 | KEY_DEST_CLASS_REG);
 120
 121         /* Sets MDHA up into an HMAC-INIT */
 122         append_operation(desc, (adata->algtype & OP_ALG_ALGSEL_MASK) |
 123                          OP_ALG_AAI_HMAC | OP_TYPE_CLASS2_ALG | OP_ALG_DECRYPT |
 124                          OP_ALG_AS_INIT);
 125
 126         /*
 127          * do a FIFO_LOAD of zero, this will trigger the internal key expansion
 128          * into both pads inside MDHA
 129          */
 130         append_fifo_load_as_imm(desc, NULL, 0, LDST_CLASS_2_CCB |
 131                                 FIFOLD_TYPE_MSG | FIFOLD_TYPE_LAST2);
 132
 133         /*
 134          * FIFO_STORE with the explicit split-key content store
 135          * (0x26 output type)
 136          */
 137         append_fifo_store(desc, dma_addr_out, adata->keylen,
 138                           LDST_CLASS_2_CCB | FIFOST_TYPE_SPLIT_KEK);
 139
 140 #ifdef DEBUG
 141         print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
 142                        DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
 143         print_hex_dump(KERN_ERR, "jobdesc@"__stringify(__LINE__)": ",
 144                        DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1);
 145 #endif
 146
 147         result.err = 0;
 148         init_completion(&result.completion);
 149
 150         ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
 151         if (!ret) {
 152                 /* in progress */
 153                 wait_for_completion(&result.completion);
 154                 ret = result.err;
 155 #ifdef DEBUG
 156                 print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
 157                                DUMP_PREFIX_ADDRESS, 16, 4, key_out,
 158                                adata->keylen_pad, 1);
 159 #endif
 160         }
 161
 162         dma_unmap_single(jrdev, dma_addr_out, adata->keylen_pad,
 163                          DMA_FROM_DEVICE);
 164 out_unmap_in:
 165         dma_unmap_single(jrdev, dma_addr_in, keylen, DMA_TO_DEVICE);
 166 out_free:
 167         kfree(desc);
 168         return ret;
 169 }
 170 EXPORT_SYMBOL(gen_split_key);