1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2015 Pengutronix, Steffen Trumtrar <kernel@pengutronix.de> 4 * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> 5 */ 6 7 #define pr_fmt(fmt) "caam blob_gen: " fmt 8 9 #include <linux/device.h> 10 #include <soc/fsl/caam-blob.h> 11 12 #include "compat.h" 13 #include "desc_constr.h" 14 #include "desc.h" 15 #include "error.h" 16 #include "intern.h" 17 #include "jr.h" 18 #include "regs.h" 19 20 #define CAAM_BLOB_DESC_BYTES_MAX \ 21 /* Command to initialize & stating length of descriptor */ \ 22 (CAAM_CMD_SZ + \ 23 /* Command to append the key-modifier + key-modifier data */ \ 24 CAAM_CMD_SZ + CAAM_BLOB_KEYMOD_LENGTH + \ 25 /* Command to include input key + pointer to the input key */ \ 26 CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \ 27 /* Command to include output key + pointer to the output key */ \ 28 CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \ 29 /* Command describing the operation to perform */ \ 30 CAAM_CMD_SZ) 31 32 struct caam_blob_priv { 33 struct device jrdev; 34 }; 35 36 struct caam_blob_job_result { 37 int err; 38 struct completion completion; 39 }; 40 41 static void caam_blob_job_done(struct device *dev, u32 *desc, u32 err, void *context) 42 { 43 struct caam_blob_job_result *res = context; 44 int ecode = 0; 45 46 dev_dbg(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err); 47 48 if (err) 49 ecode = caam_jr_strstatus(dev, err); 50 51 res->err = ecode; 52 53 /* 54 * Upon completion, desc points to a buffer containing a CAAM job 55 * descriptor which encapsulates data into an externally-storable 56 * blob. 57 */ 58 complete(&res->completion); 59 } 60 61 int caam_process_blob(struct caam_blob_priv *priv, 62 struct caam_blob_info *info, bool encap) 63 { 64 struct caam_blob_job_result testres; 65 struct device *jrdev = &priv->jrdev; 66 dma_addr_t dma_in, dma_out; 67 int op = OP_PCLID_BLOB; 68 size_t output_len; 69 u32 *desc; 70 int ret; 71 72 if (info->key_mod_len > CAAM_BLOB_KEYMOD_LENGTH) 73 return -EINVAL; 74 75 if (encap) { 76 op |= OP_TYPE_ENCAP_PROTOCOL; 77 output_len = info->input_len + CAAM_BLOB_OVERHEAD; 78 } else { 79 op |= OP_TYPE_DECAP_PROTOCOL; 80 output_len = info->input_len - CAAM_BLOB_OVERHEAD; 81 } 82 83 desc = kzalloc(CAAM_BLOB_DESC_BYTES_MAX, GFP_KERNEL | GFP_DMA); 84 if (!desc) 85 return -ENOMEM; 86 87 dma_in = dma_map_single(jrdev, info->input, info->input_len, 88 DMA_TO_DEVICE); 89 if (dma_mapping_error(jrdev, dma_in)) { 90 dev_err(jrdev, "unable to map input DMA buffer\n"); 91 ret = -ENOMEM; 92 goto out_free; 93 } 94 95 dma_out = dma_map_single(jrdev, info->output, output_len, 96 DMA_FROM_DEVICE); 97 if (dma_mapping_error(jrdev, dma_out)) { 98 dev_err(jrdev, "unable to map output DMA buffer\n"); 99 ret = -ENOMEM; 100 goto out_unmap_in; 101 } 102 103 /* 104 * A data blob is encrypted using a blob key (BK); a random number. 105 * The BK is used as an AES-CCM key. The initial block (B0) and the 106 * initial counter (Ctr0) are generated automatically and stored in 107 * Class 1 Context DWords 0+1+2+3. The random BK is stored in the 108 * Class 1 Key Register. Operation Mode is set to AES-CCM. 109 */ 110 111 init_job_desc(desc, 0); 112 append_key_as_imm(desc, info->key_mod, info->key_mod_len, 113 info->key_mod_len, CLASS_2 | KEY_DEST_CLASS_REG); 114 append_seq_in_ptr_intlen(desc, dma_in, info->input_len, 0); 115 append_seq_out_ptr_intlen(desc, dma_out, output_len, 0); 116 append_operation(desc, op); 117 118 print_hex_dump_debug("data@"__stringify(__LINE__)": ", 119 DUMP_PREFIX_ADDRESS, 16, 1, info->input, 120 info->input_len, false); 121 print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ", 122 DUMP_PREFIX_ADDRESS, 16, 1, desc, 123 desc_bytes(desc), false); 124 125 testres.err = 0; 126 init_completion(&testres.completion); 127 128 ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres); 129 if (ret == -EINPROGRESS) { 130 wait_for_completion(&testres.completion); 131 ret = testres.err; 132 print_hex_dump_debug("output@"__stringify(__LINE__)": ", 133 DUMP_PREFIX_ADDRESS, 16, 1, info->output, 134 output_len, false); 135 } 136 137 if (ret == 0) 138 info->output_len = output_len; 139 140 dma_unmap_single(jrdev, dma_out, output_len, DMA_FROM_DEVICE); 141 out_unmap_in: 142 dma_unmap_single(jrdev, dma_in, info->input_len, DMA_TO_DEVICE); 143 out_free: 144 kfree(desc); 145 146 return ret; 147 } 148 EXPORT_SYMBOL(caam_process_blob); 149 150 struct caam_blob_priv *caam_blob_gen_init(void) 151 { 152 struct caam_drv_private *ctrlpriv; 153 struct device *jrdev; 154 155 /* 156 * caam_blob_gen_init() may expectedly fail with -ENODEV, e.g. when 157 * CAAM driver didn't probe or when SoC lacks BLOB support. An 158 * error would be harsh in this case, so we stick to info level. 159 */ 160 161 jrdev = caam_jr_alloc(); 162 if (IS_ERR(jrdev)) { 163 pr_info("job ring requested, but none currently available\n"); 164 return ERR_PTR(-ENODEV); 165 } 166 167 ctrlpriv = dev_get_drvdata(jrdev->parent); 168 if (!ctrlpriv->blob_present) { 169 dev_info(jrdev, "no hardware blob generation support\n"); 170 caam_jr_free(jrdev); 171 return ERR_PTR(-ENODEV); 172 } 173 174 return container_of(jrdev, struct caam_blob_priv, jrdev); 175 } 176 EXPORT_SYMBOL(caam_blob_gen_init); 177 178 void caam_blob_gen_exit(struct caam_blob_priv *priv) 179 { 180 caam_jr_free(&priv->jrdev); 181 } 182 EXPORT_SYMBOL(caam_blob_gen_exit); 183