Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 1 | /* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 2 | * |
| 3 | * This program is free software; you can redistribute it and/or modify |
| 4 | * it under the terms of the GNU General Public License version 2 and |
| 5 | * only version 2 as published by the Free Software Foundation. |
| 6 | * |
| 7 | * This program is distributed in the hope that it will be useful, |
| 8 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 9 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 10 | * GNU General Public License for more details. |
| 11 | * |
| 12 | */ |
| 13 | |
| 14 | #include <linux/slab.h> |
| 15 | #include <linux/uaccess.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/kernel.h> |
| 18 | #include <linux/errno.h> |
| 19 | #include <linux/io.h> |
| 20 | #include <linux/string.h> |
| 21 | #include <linux/qmi_encdec.h> |
| 22 | |
| 23 | #include "qmi_encdec_priv.h" |
| 24 | |
| 25 | #define TLV_LEN_SIZE sizeof(uint16_t) |
| 26 | #define TLV_TYPE_SIZE sizeof(uint8_t) |
| 27 | |
Karthikeyan Ramasubramanian | dc4d563 | 2012-11-07 19:42:25 -0700 | [diff] [blame] | 28 | #ifdef CONFIG_QMI_ENCDEC_DEBUG |
| 29 | |
| 30 | #define qmi_encdec_dump(prefix_str, buf, buf_len) do { \ |
| 31 | const u8 *ptr = buf; \ |
| 32 | int i, linelen, remaining = buf_len; \ |
| 33 | int rowsize = 16, groupsize = 1; \ |
| 34 | unsigned char linebuf[256]; \ |
| 35 | for (i = 0; i < buf_len; i += rowsize) { \ |
| 36 | linelen = min(remaining, rowsize); \ |
| 37 | remaining -= linelen; \ |
| 38 | hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, \ |
| 39 | linebuf, sizeof(linebuf), false); \ |
| 40 | pr_debug("%s: %s\n", prefix_str, linebuf); \ |
| 41 | } \ |
| 42 | } while (0) |
| 43 | |
| 44 | #define QMI_ENCODE_LOG_MSG(buf, buf_len) do { \ |
| 45 | qmi_encdec_dump("QMI_ENCODE_MSG", buf, buf_len); \ |
| 46 | } while (0) |
| 47 | |
| 48 | #define QMI_DECODE_LOG_MSG(buf, buf_len) do { \ |
| 49 | qmi_encdec_dump("QMI_DECODE_MSG", buf, buf_len); \ |
| 50 | } while (0) |
| 51 | |
| 52 | #define QMI_ENCODE_LOG_ELEM(level, elem_len, elem_size, buf) do { \ |
| 53 | pr_debug("QMI_ENCODE_ELEM lvl: %d, len: %d, size: %d\n", \ |
| 54 | level, elem_len, elem_size); \ |
| 55 | qmi_encdec_dump("QMI_ENCODE_ELEM", buf, (elem_len * elem_size)); \ |
| 56 | } while (0) |
| 57 | |
| 58 | #define QMI_DECODE_LOG_ELEM(level, elem_len, elem_size, buf) do { \ |
| 59 | pr_debug("QMI_DECODE_ELEM lvl: %d, len: %d, size: %d\n", \ |
| 60 | level, elem_len, elem_size); \ |
| 61 | qmi_encdec_dump("QMI_DECODE_ELEM", buf, (elem_len * elem_size)); \ |
| 62 | } while (0) |
| 63 | |
| 64 | #define QMI_ENCODE_LOG_TLV(tlv_type, tlv_len) do { \ |
| 65 | pr_debug("QMI_ENCODE_TLV type: %d, len: %d\n", tlv_type, tlv_len); \ |
| 66 | } while (0) |
| 67 | |
| 68 | #define QMI_DECODE_LOG_TLV(tlv_type, tlv_len) do { \ |
| 69 | pr_debug("QMI_DECODE_TLV type: %d, len: %d\n", tlv_type, tlv_len); \ |
| 70 | } while (0) |
| 71 | |
| 72 | #else |
| 73 | |
| 74 | #define QMI_ENCODE_LOG_MSG(buf, buf_len) { } |
| 75 | #define QMI_DECODE_LOG_MSG(buf, buf_len) { } |
| 76 | #define QMI_ENCODE_LOG_ELEM(level, elem_len, elem_size, buf) { } |
| 77 | #define QMI_DECODE_LOG_ELEM(level, elem_len, elem_size, buf) { } |
| 78 | #define QMI_ENCODE_LOG_TLV(tlv_type, tlv_len) { } |
| 79 | #define QMI_DECODE_LOG_TLV(tlv_type, tlv_len) { } |
| 80 | |
| 81 | #endif |
| 82 | |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 83 | static int _qmi_kernel_encode(struct elem_info *ei_array, |
| 84 | void *out_buf, void *in_c_struct, |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 85 | uint32_t out_buf_len, int enc_level); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 86 | |
| 87 | static int _qmi_kernel_decode(struct elem_info *ei_array, |
| 88 | void *out_c_struct, |
| 89 | void *in_buf, uint32_t in_buf_len, |
| 90 | int dec_level); |
| 91 | |
| 92 | /** |
Karthikeyan Ramasubramanian | 0714f1b | 2013-01-08 17:21:53 -0700 | [diff] [blame] | 93 | * qmi_calc_max_msg_len() - Calculate the maximum length of a QMI message |
| 94 | * @ei_array: Struct info array describing the structure. |
| 95 | * @level: Level to identify the depth of the nested structures. |
| 96 | * |
| 97 | * @return: expected maximum length of the QMI message or 0 on failure. |
| 98 | */ |
| 99 | static int qmi_calc_max_msg_len(struct elem_info *ei_array, |
| 100 | int level) |
| 101 | { |
| 102 | int max_msg_len = 0; |
| 103 | struct elem_info *temp_ei; |
| 104 | |
| 105 | if (!ei_array) |
| 106 | return max_msg_len; |
| 107 | |
| 108 | for (temp_ei = ei_array; temp_ei->data_type != QMI_EOTI; temp_ei++) { |
| 109 | /* Flag to identify the optional element is not encoded */ |
| 110 | if (temp_ei->data_type == QMI_OPT_FLAG) |
| 111 | continue; |
| 112 | |
| 113 | if (temp_ei->data_type == QMI_DATA_LEN) { |
| 114 | max_msg_len += (temp_ei->elem_size == sizeof(uint8_t) ? |
| 115 | sizeof(uint8_t) : sizeof(uint16_t)); |
| 116 | continue; |
| 117 | } else if (temp_ei->data_type == QMI_STRUCT) { |
| 118 | max_msg_len += qmi_calc_max_msg_len(temp_ei->ei_array, |
| 119 | (level + 1)); |
| 120 | } else { |
| 121 | max_msg_len += (temp_ei->elem_len * temp_ei->elem_size); |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * Type & Length info. not prepended for elements in the |
| 126 | * nested structure. |
| 127 | */ |
| 128 | if (level == 1) |
| 129 | max_msg_len += (TLV_TYPE_SIZE + TLV_LEN_SIZE); |
| 130 | } |
| 131 | return max_msg_len; |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * qmi_verify_max_msg_len() - Verify the maximum length of a QMI message |
| 136 | * @desc: Pointer to structure descriptor. |
| 137 | * |
| 138 | * @return: true if the maximum message length embedded in structure |
| 139 | * descriptor matches the calculated value, else false. |
| 140 | */ |
| 141 | bool qmi_verify_max_msg_len(struct msg_desc *desc) |
| 142 | { |
| 143 | int calc_max_msg_len; |
| 144 | |
| 145 | if (!desc) |
| 146 | return false; |
| 147 | |
| 148 | calc_max_msg_len = qmi_calc_max_msg_len(desc->ei_array, 1); |
| 149 | if (calc_max_msg_len != desc->max_msg_len) { |
| 150 | pr_err("%s: Calc. len %d != Passed len %d\n", |
| 151 | __func__, calc_max_msg_len, desc->max_msg_len); |
| 152 | return false; |
| 153 | } |
| 154 | return true; |
| 155 | } |
| 156 | |
| 157 | /** |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 158 | * qmi_kernel_encode() - Encode to QMI message wire format |
| 159 | * @desc: Pointer to structure descriptor. |
| 160 | * @out_buf: Buffer to hold the encoded QMI message. |
| 161 | * @out_buf_len: Length of the out buffer. |
| 162 | * @in_c_struct: C Structure to be encoded. |
| 163 | * |
| 164 | * @return: size of encoded message on success, < 0 for error. |
| 165 | */ |
| 166 | int qmi_kernel_encode(struct msg_desc *desc, |
| 167 | void *out_buf, uint32_t out_buf_len, |
| 168 | void *in_c_struct) |
| 169 | { |
| 170 | int enc_level = 1; |
Karthikeyan Ramasubramanian | 0714f1b | 2013-01-08 17:21:53 -0700 | [diff] [blame] | 171 | int ret, calc_max_msg_len; |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 172 | |
| 173 | if (!desc || !desc->ei_array) |
| 174 | return -EINVAL; |
| 175 | |
| 176 | if (!out_buf || !in_c_struct) |
| 177 | return -EINVAL; |
| 178 | |
| 179 | if (desc->max_msg_len < out_buf_len) |
| 180 | return -ETOOSMALL; |
| 181 | |
Karthikeyan Ramasubramanian | 0714f1b | 2013-01-08 17:21:53 -0700 | [diff] [blame] | 182 | ret = _qmi_kernel_encode(desc->ei_array, out_buf, |
| 183 | in_c_struct, out_buf_len, enc_level); |
| 184 | if (ret == -ETOOSMALL) { |
| 185 | calc_max_msg_len = qmi_calc_max_msg_len(desc->ei_array, 1); |
| 186 | pr_err("%s: Calc. len %d != Out buf len %d\n", |
| 187 | __func__, calc_max_msg_len, out_buf_len); |
| 188 | } |
| 189 | return ret; |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 190 | } |
| 191 | EXPORT_SYMBOL(qmi_kernel_encode); |
| 192 | |
| 193 | /** |
| 194 | * qmi_encode_basic_elem() - Encodes elements of basic/primary data type |
| 195 | * @buf_dst: Buffer to store the encoded information. |
| 196 | * @buf_src: Buffer containing the elements to be encoded. |
| 197 | * @elem_len: Number of elements, in the buf_src, to be encoded. |
| 198 | * @elem_size: Size of a single instance of the element to be encoded. |
| 199 | * |
| 200 | * @return: number of bytes of encoded information. |
| 201 | * |
| 202 | * This function encodes the "elem_len" number of data elements, each of |
| 203 | * size "elem_size" bytes from the source buffer "buf_src" and stores the |
| 204 | * encoded information in the destination buffer "buf_dst". The elements are |
| 205 | * of primary data type which include uint8_t - uint64_t or similar. This |
| 206 | * function returns the number of bytes of encoded information. |
| 207 | */ |
| 208 | static int qmi_encode_basic_elem(void *buf_dst, void *buf_src, |
| 209 | uint32_t elem_len, uint32_t elem_size) |
| 210 | { |
| 211 | uint32_t i, rc = 0; |
| 212 | |
| 213 | for (i = 0; i < elem_len; i++) { |
| 214 | QMI_ENCDEC_ENCODE_N_BYTES(buf_dst, buf_src, elem_size); |
| 215 | rc += elem_size; |
| 216 | } |
| 217 | |
| 218 | return rc; |
| 219 | } |
| 220 | |
| 221 | /** |
| 222 | * qmi_encode_struct_elem() - Encodes elements of struct data type |
| 223 | * @ei_array: Struct info array descibing the struct element. |
| 224 | * @buf_dst: Buffer to store the encoded information. |
| 225 | * @buf_src: Buffer containing the elements to be encoded. |
| 226 | * @elem_len: Number of elements, in the buf_src, to be encoded. |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 227 | * @out_buf_len: Available space in the encode buffer. |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 228 | * @enc_level: Depth of the nested structure from the main structure. |
| 229 | * |
| 230 | * @return: Mumber of bytes of encoded information, on success. |
| 231 | * < 0 on error. |
| 232 | * |
| 233 | * This function encodes the "elem_len" number of struct elements, each of |
| 234 | * size "ei_array->elem_size" bytes from the source buffer "buf_src" and |
| 235 | * stores the encoded information in the destination buffer "buf_dst". The |
| 236 | * elements are of struct data type which includes any C structure. This |
| 237 | * function returns the number of bytes of encoded information. |
| 238 | */ |
| 239 | static int qmi_encode_struct_elem(struct elem_info *ei_array, |
| 240 | void *buf_dst, void *buf_src, |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 241 | uint32_t elem_len, uint32_t out_buf_len, |
| 242 | int enc_level) |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 243 | { |
| 244 | int i, rc, encoded_bytes = 0; |
| 245 | struct elem_info *temp_ei = ei_array; |
| 246 | |
| 247 | for (i = 0; i < elem_len; i++) { |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 248 | rc = _qmi_kernel_encode(temp_ei->ei_array, buf_dst, buf_src, |
| 249 | (out_buf_len - encoded_bytes), |
| 250 | enc_level); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 251 | if (rc < 0) { |
| 252 | pr_err("%s: STRUCT Encode failure\n", __func__); |
| 253 | return rc; |
| 254 | } |
| 255 | buf_dst = buf_dst + rc; |
| 256 | buf_src = buf_src + temp_ei->elem_size; |
| 257 | encoded_bytes += rc; |
| 258 | } |
| 259 | |
| 260 | return encoded_bytes; |
| 261 | } |
| 262 | |
| 263 | /** |
| 264 | * skip_to_next_elem() - Skip to next element in the structure to be encoded |
| 265 | * @ei_array: Struct info describing the element to be skipped. |
| 266 | * |
| 267 | * @return: Struct info of the next element that can be encoded. |
| 268 | * |
| 269 | * This function is used while encoding optional elements. If the flag |
| 270 | * corresponding to an optional element is not set, then encoding the |
| 271 | * optional element can be skipped. This function can be used to perform |
| 272 | * that operation. |
| 273 | */ |
| 274 | static struct elem_info *skip_to_next_elem(struct elem_info *ei_array) |
| 275 | { |
| 276 | struct elem_info *temp_ei = ei_array; |
| 277 | uint8_t tlv_type; |
| 278 | |
| 279 | do { |
| 280 | tlv_type = temp_ei->tlv_type; |
| 281 | temp_ei = temp_ei + 1; |
| 282 | } while (tlv_type == temp_ei->tlv_type); |
| 283 | |
| 284 | return temp_ei; |
| 285 | } |
| 286 | |
| 287 | /** |
| 288 | * _qmi_kernel_encode() - Core Encode Function |
| 289 | * @ei_array: Struct info array describing the structure to be encoded. |
| 290 | * @out_buf: Buffer to hold the encoded QMI message. |
| 291 | * @in_c_struct: Pointer to the C structure to be encoded. |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 292 | * @out_buf_len: Available space in the encode buffer. |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 293 | * @enc_level: Encode level to indicate the depth of the nested structure, |
| 294 | * within the main structure, being encoded. |
| 295 | * |
| 296 | * @return: Number of bytes of encoded information, on success. |
| 297 | * < 0 on error. |
| 298 | */ |
| 299 | static int _qmi_kernel_encode(struct elem_info *ei_array, |
| 300 | void *out_buf, void *in_c_struct, |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 301 | uint32_t out_buf_len, int enc_level) |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 302 | { |
| 303 | struct elem_info *temp_ei = ei_array; |
| 304 | uint8_t opt_flag_value = 0; |
| 305 | uint32_t data_len_value = 0, data_len_sz; |
| 306 | uint8_t *buf_dst = (uint8_t *)out_buf; |
| 307 | uint8_t *tlv_pointer; |
| 308 | uint32_t tlv_len; |
| 309 | uint8_t tlv_type; |
| 310 | uint32_t encoded_bytes = 0; |
| 311 | void *buf_src; |
| 312 | int encode_tlv = 0; |
| 313 | int rc; |
| 314 | |
| 315 | tlv_pointer = buf_dst; |
| 316 | tlv_len = 0; |
| 317 | buf_dst = buf_dst + (TLV_LEN_SIZE + TLV_TYPE_SIZE); |
| 318 | |
| 319 | while (temp_ei->data_type != QMI_EOTI) { |
| 320 | buf_src = in_c_struct + temp_ei->offset; |
| 321 | tlv_type = temp_ei->tlv_type; |
| 322 | |
| 323 | if (temp_ei->is_array == NO_ARRAY) { |
| 324 | data_len_value = 1; |
| 325 | } else if (temp_ei->is_array == STATIC_ARRAY) { |
| 326 | data_len_value = temp_ei->elem_len; |
| 327 | } else if (data_len_value <= 0 || |
| 328 | temp_ei->elem_len < data_len_value) { |
| 329 | pr_err("%s: Invalid data length\n", __func__); |
| 330 | return -EINVAL; |
| 331 | } |
| 332 | |
| 333 | switch (temp_ei->data_type) { |
| 334 | case QMI_OPT_FLAG: |
| 335 | rc = qmi_encode_basic_elem(&opt_flag_value, buf_src, |
| 336 | 1, sizeof(uint8_t)); |
| 337 | if (opt_flag_value) |
| 338 | temp_ei = temp_ei + 1; |
| 339 | else |
| 340 | temp_ei = skip_to_next_elem(temp_ei); |
| 341 | break; |
| 342 | |
| 343 | case QMI_DATA_LEN: |
| 344 | memcpy(&data_len_value, buf_src, temp_ei->elem_size); |
| 345 | data_len_sz = temp_ei->elem_size == sizeof(uint8_t) ? |
| 346 | sizeof(uint8_t) : sizeof(uint16_t); |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 347 | /* Check to avoid out of range buffer access */ |
| 348 | if ((data_len_sz + encoded_bytes + TLV_LEN_SIZE + |
| 349 | TLV_TYPE_SIZE) > out_buf_len) { |
| 350 | pr_err("%s: Too Small Buffer @DATA_LEN\n", |
| 351 | __func__); |
| 352 | return -ETOOSMALL; |
| 353 | } |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 354 | rc = qmi_encode_basic_elem(buf_dst, &data_len_value, |
| 355 | 1, data_len_sz); |
| 356 | if (data_len_value) { |
| 357 | UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst, |
| 358 | encoded_bytes, tlv_len, encode_tlv, rc); |
| 359 | encode_tlv = 0; |
| 360 | } else { |
| 361 | temp_ei = skip_to_next_elem(temp_ei); |
| 362 | } |
| 363 | break; |
| 364 | |
| 365 | case QMI_UNSIGNED_1_BYTE: |
| 366 | case QMI_UNSIGNED_2_BYTE: |
| 367 | case QMI_UNSIGNED_4_BYTE: |
| 368 | case QMI_UNSIGNED_8_BYTE: |
| 369 | case QMI_SIGNED_2_BYTE_ENUM: |
| 370 | case QMI_SIGNED_4_BYTE_ENUM: |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 371 | /* Check to avoid out of range buffer access */ |
| 372 | if (((data_len_value * temp_ei->elem_size) + |
| 373 | encoded_bytes + TLV_LEN_SIZE + TLV_TYPE_SIZE) > |
| 374 | out_buf_len) { |
| 375 | pr_err("%s: Too Small Buffer @data_type:%d\n", |
| 376 | __func__, temp_ei->data_type); |
| 377 | return -ETOOSMALL; |
| 378 | } |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 379 | rc = qmi_encode_basic_elem(buf_dst, buf_src, |
| 380 | data_len_value, temp_ei->elem_size); |
Karthikeyan Ramasubramanian | dc4d563 | 2012-11-07 19:42:25 -0700 | [diff] [blame] | 381 | QMI_ENCODE_LOG_ELEM(enc_level, data_len_value, |
| 382 | temp_ei->elem_size, buf_src); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 383 | UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst, |
| 384 | encoded_bytes, tlv_len, encode_tlv, rc); |
| 385 | break; |
| 386 | |
| 387 | case QMI_STRUCT: |
| 388 | rc = qmi_encode_struct_elem(temp_ei, buf_dst, buf_src, |
Karthikeyan Ramasubramanian | 31e31d7 | 2013-01-03 15:59:54 -0700 | [diff] [blame] | 389 | data_len_value, (out_buf_len - encoded_bytes), |
| 390 | (enc_level + 1)); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 391 | if (rc < 0) |
| 392 | return rc; |
| 393 | UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst, |
| 394 | encoded_bytes, tlv_len, encode_tlv, rc); |
| 395 | break; |
| 396 | |
| 397 | default: |
| 398 | pr_err("%s: Unrecognized data type\n", __func__); |
| 399 | return -EINVAL; |
| 400 | |
| 401 | } |
| 402 | |
| 403 | if (encode_tlv && enc_level == 1) { |
| 404 | QMI_ENCDEC_ENCODE_TLV(tlv_type, tlv_len, tlv_pointer); |
Karthikeyan Ramasubramanian | dc4d563 | 2012-11-07 19:42:25 -0700 | [diff] [blame] | 405 | QMI_ENCODE_LOG_TLV(tlv_type, tlv_len); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 406 | encoded_bytes += (TLV_TYPE_SIZE + TLV_LEN_SIZE); |
| 407 | tlv_pointer = buf_dst; |
| 408 | tlv_len = 0; |
| 409 | buf_dst = buf_dst + TLV_LEN_SIZE + TLV_TYPE_SIZE; |
| 410 | encode_tlv = 0; |
| 411 | } |
| 412 | } |
Karthikeyan Ramasubramanian | dc4d563 | 2012-11-07 19:42:25 -0700 | [diff] [blame] | 413 | QMI_ENCODE_LOG_MSG(out_buf, encoded_bytes); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 414 | return encoded_bytes; |
| 415 | } |
| 416 | |
| 417 | /** |
| 418 | * qmi_kernel_decode() - Decode to C Structure format |
| 419 | * @desc: Pointer to structure descriptor. |
| 420 | * @out_c_struct: Buffer to hold the decoded C structure. |
| 421 | * @in_buf: Buffer containg the QMI message to be decoded. |
| 422 | * @in_buf_len: Length of the incoming QMI message. |
| 423 | * |
| 424 | * @return: 0 on success, < 0 on error. |
| 425 | */ |
| 426 | int qmi_kernel_decode(struct msg_desc *desc, void *out_c_struct, |
| 427 | void *in_buf, uint32_t in_buf_len) |
| 428 | { |
| 429 | int dec_level = 1; |
| 430 | int rc = 0; |
| 431 | |
| 432 | if (!desc || !desc->ei_array) |
| 433 | return -EINVAL; |
| 434 | |
| 435 | if (!out_c_struct || !in_buf || !in_buf_len) |
| 436 | return -EINVAL; |
| 437 | |
| 438 | if (desc->max_msg_len < in_buf_len) |
| 439 | return -EINVAL; |
| 440 | |
| 441 | rc = _qmi_kernel_decode(desc->ei_array, out_c_struct, |
| 442 | in_buf, in_buf_len, dec_level); |
| 443 | if (rc < 0) |
| 444 | return rc; |
| 445 | else |
| 446 | return 0; |
| 447 | } |
| 448 | EXPORT_SYMBOL(qmi_kernel_decode); |
| 449 | |
| 450 | /** |
| 451 | * qmi_decode_basic_elem() - Decodes elements of basic/primary data type |
| 452 | * @buf_dst: Buffer to store the decoded element. |
| 453 | * @buf_src: Buffer containing the elements in QMI wire format. |
| 454 | * @elem_len: Number of elements to be decoded. |
| 455 | * @elem_size: Size of a single instance of the element to be decoded. |
| 456 | * |
| 457 | * @return: Total size of the decoded data elements, in bytes. |
| 458 | * |
| 459 | * This function decodes the "elem_len" number of elements in QMI wire format, |
| 460 | * each of size "elem_size" bytes from the source buffer "buf_src" and stores |
| 461 | * the decoded elements in the destination buffer "buf_dst". The elements are |
| 462 | * of primary data type which include uint8_t - uint64_t or similar. This |
| 463 | * function returns the number of bytes of decoded information. |
| 464 | */ |
| 465 | static int qmi_decode_basic_elem(void *buf_dst, void *buf_src, |
| 466 | uint32_t elem_len, uint32_t elem_size) |
| 467 | { |
| 468 | uint32_t i, rc = 0; |
| 469 | |
| 470 | for (i = 0; i < elem_len; i++) { |
| 471 | QMI_ENCDEC_DECODE_N_BYTES(buf_dst, buf_src, elem_size); |
| 472 | rc += elem_size; |
| 473 | } |
| 474 | |
| 475 | return rc; |
| 476 | } |
| 477 | |
| 478 | /** |
| 479 | * qmi_decode_struct_elem() - Decodes elements of struct data type |
| 480 | * @ei_array: Struct info array descibing the struct element. |
| 481 | * @buf_dst: Buffer to store the decoded element. |
| 482 | * @buf_src: Buffer containing the elements in QMI wire format. |
| 483 | * @elem_len: Number of elements to be decoded. |
| 484 | * @tlv_len: Total size of the encoded inforation corresponding to |
| 485 | * this struct element. |
| 486 | * @dec_level: Depth of the nested structure from the main structure. |
| 487 | * |
| 488 | * @return: Total size of the decoded data elements, on success. |
| 489 | * < 0 on error. |
| 490 | * |
| 491 | * This function decodes the "elem_len" number of elements in QMI wire format, |
| 492 | * each of size "(tlv_len/elem_len)" bytes from the source buffer "buf_src" |
| 493 | * and stores the decoded elements in the destination buffer "buf_dst". The |
| 494 | * elements are of struct data type which includes any C structure. This |
| 495 | * function returns the number of bytes of decoded information. |
| 496 | */ |
| 497 | static int qmi_decode_struct_elem(struct elem_info *ei_array, void *buf_dst, |
| 498 | void *buf_src, uint32_t elem_len, |
| 499 | uint32_t tlv_len, int dec_level) |
| 500 | { |
| 501 | int i, rc, decoded_bytes = 0; |
| 502 | struct elem_info *temp_ei = ei_array; |
| 503 | |
| 504 | for (i = 0; i < elem_len; i++) { |
| 505 | rc = _qmi_kernel_decode(temp_ei->ei_array, buf_dst, buf_src, |
| 506 | (tlv_len/elem_len), dec_level); |
| 507 | if (rc < 0) |
| 508 | return rc; |
| 509 | if (rc != (tlv_len/elem_len)) { |
| 510 | pr_err("%s: Fault in decoding\n", __func__); |
| 511 | return -EFAULT; |
| 512 | } |
| 513 | buf_src = buf_src + rc; |
| 514 | buf_dst = buf_dst + temp_ei->elem_size; |
| 515 | decoded_bytes += rc; |
| 516 | } |
| 517 | |
| 518 | return decoded_bytes; |
| 519 | } |
| 520 | |
| 521 | /** |
| 522 | * find_ei() - Find element info corresponding to TLV Type |
| 523 | * @ei_array: Struct info array of the message being decoded. |
| 524 | * @type: TLV Type of the element being searched. |
| 525 | * |
| 526 | * @return: Pointer to struct info, if found |
| 527 | * |
| 528 | * Every element that got encoded in the QMI message will have a type |
| 529 | * information associated with it. While decoding the QMI message, |
| 530 | * this function is used to find the struct info regarding the element |
| 531 | * that corresponds to the type being decoded. |
| 532 | */ |
| 533 | static struct elem_info *find_ei(struct elem_info *ei_array, |
| 534 | uint32_t type) |
| 535 | { |
| 536 | struct elem_info *temp_ei = ei_array; |
| 537 | while (temp_ei->data_type != QMI_EOTI) { |
| 538 | if (temp_ei->tlv_type == (uint8_t)type) |
| 539 | return temp_ei; |
| 540 | temp_ei = temp_ei + 1; |
| 541 | } |
| 542 | return NULL; |
| 543 | } |
| 544 | |
| 545 | /** |
| 546 | * _qmi_kernel_decode() - Core Decode Function |
| 547 | * @ei_array: Struct info array describing the structure to be decoded. |
| 548 | * @out_c_struct: Buffer to hold the decoded C struct |
| 549 | * @in_buf: Buffer containing the QMI message to be decoded |
| 550 | * @in_buf_len: Length of the QMI message to be decoded |
| 551 | * @dec_level: Decode level to indicate the depth of the nested structure, |
| 552 | * within the main structure, being decoded |
| 553 | * |
| 554 | * @return: Number of bytes of decoded information, on success |
| 555 | * < 0 on error. |
| 556 | */ |
| 557 | static int _qmi_kernel_decode(struct elem_info *ei_array, |
| 558 | void *out_c_struct, |
| 559 | void *in_buf, uint32_t in_buf_len, |
| 560 | int dec_level) |
| 561 | { |
| 562 | struct elem_info *temp_ei = ei_array; |
| 563 | uint8_t opt_flag_value = 1; |
| 564 | uint32_t data_len_value = 0, data_len_sz = 0; |
| 565 | uint8_t *buf_dst = out_c_struct; |
| 566 | uint8_t *tlv_pointer; |
| 567 | uint32_t tlv_len = 0; |
| 568 | uint32_t tlv_type; |
| 569 | uint32_t decoded_bytes = 0; |
| 570 | void *buf_src = in_buf; |
| 571 | int rc; |
| 572 | |
Karthikeyan Ramasubramanian | dc4d563 | 2012-11-07 19:42:25 -0700 | [diff] [blame] | 573 | QMI_DECODE_LOG_MSG(in_buf, in_buf_len); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 574 | while (decoded_bytes < in_buf_len) { |
| 575 | if (dec_level == 1) { |
| 576 | tlv_pointer = buf_src; |
| 577 | QMI_ENCDEC_DECODE_TLV(&tlv_type, |
| 578 | &tlv_len, tlv_pointer); |
Karthikeyan Ramasubramanian | dc4d563 | 2012-11-07 19:42:25 -0700 | [diff] [blame] | 579 | QMI_DECODE_LOG_TLV(tlv_type, tlv_len); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 580 | buf_src += (TLV_TYPE_SIZE + TLV_LEN_SIZE); |
| 581 | decoded_bytes += (TLV_TYPE_SIZE + TLV_LEN_SIZE); |
| 582 | temp_ei = find_ei(ei_array, tlv_type); |
| 583 | if (!temp_ei) { |
| 584 | pr_err("%s: Inval element info\n", __func__); |
| 585 | return -EINVAL; |
| 586 | } |
| 587 | } |
| 588 | |
| 589 | buf_dst = out_c_struct + temp_ei->offset; |
| 590 | if (temp_ei->data_type == QMI_OPT_FLAG) { |
| 591 | memcpy(buf_dst, &opt_flag_value, sizeof(uint8_t)); |
| 592 | temp_ei = temp_ei + 1; |
| 593 | buf_dst = out_c_struct + temp_ei->offset; |
| 594 | } |
| 595 | |
| 596 | if (temp_ei->data_type == QMI_DATA_LEN) { |
| 597 | data_len_sz = temp_ei->elem_size == sizeof(uint8_t) ? |
| 598 | sizeof(uint8_t) : sizeof(uint16_t); |
| 599 | rc = qmi_decode_basic_elem(&data_len_value, buf_src, |
| 600 | 1, data_len_sz); |
| 601 | memcpy(buf_dst, &data_len_value, sizeof(uint32_t)); |
| 602 | temp_ei = temp_ei + 1; |
| 603 | buf_dst = out_c_struct + temp_ei->offset; |
| 604 | UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc); |
| 605 | } |
| 606 | |
| 607 | if (temp_ei->is_array == NO_ARRAY) { |
| 608 | data_len_value = 1; |
| 609 | } else if (temp_ei->is_array == STATIC_ARRAY) { |
| 610 | data_len_value = temp_ei->elem_len; |
| 611 | } else if (data_len_value > temp_ei->elem_len) { |
| 612 | pr_err("%s: Data len %d > max spec %d\n", |
| 613 | __func__, data_len_value, temp_ei->elem_len); |
| 614 | return -ETOOSMALL; |
| 615 | } |
| 616 | |
| 617 | switch (temp_ei->data_type) { |
| 618 | case QMI_UNSIGNED_1_BYTE: |
| 619 | case QMI_UNSIGNED_2_BYTE: |
| 620 | case QMI_UNSIGNED_4_BYTE: |
| 621 | case QMI_UNSIGNED_8_BYTE: |
| 622 | case QMI_SIGNED_2_BYTE_ENUM: |
| 623 | case QMI_SIGNED_4_BYTE_ENUM: |
| 624 | rc = qmi_decode_basic_elem(buf_dst, buf_src, |
| 625 | data_len_value, temp_ei->elem_size); |
Karthikeyan Ramasubramanian | dc4d563 | 2012-11-07 19:42:25 -0700 | [diff] [blame] | 626 | QMI_DECODE_LOG_ELEM(dec_level, data_len_value, |
| 627 | temp_ei->elem_size, buf_dst); |
Karthikeyan Ramasubramanian | d952258 | 2012-07-18 19:25:37 -0600 | [diff] [blame] | 628 | UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc); |
| 629 | break; |
| 630 | |
| 631 | case QMI_STRUCT: |
| 632 | rc = qmi_decode_struct_elem(temp_ei, buf_dst, buf_src, |
| 633 | data_len_value, tlv_len, (dec_level + 1)); |
| 634 | if (rc < 0) |
| 635 | return rc; |
| 636 | UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc); |
| 637 | break; |
| 638 | default: |
| 639 | pr_err("%s: Unrecognized data type\n", __func__); |
| 640 | return -EINVAL; |
| 641 | } |
| 642 | temp_ei = temp_ei + 1; |
| 643 | } |
| 644 | return decoded_bytes; |
| 645 | } |
| 646 | MODULE_DESCRIPTION("QMI kernel enc/dec"); |
| 647 | MODULE_LICENSE("GPL v2"); |