diff options
author | Karthikeyan Ramasubramanian <kramasub@codeaurora.org> | 2016-02-03 14:20:26 -0700 |
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committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-22 11:08:08 -0700 |
commit | cdb2ce4239f547fe7c680f875a07dcb7dd39c3a7 (patch) | |
tree | e6d784b7fafa72cb84a82d4bc5d4e4da44cc2851 /lib | |
parent | 7c45a7bcfa99ef68330b208566955e64221331de (diff) |
soc: qcom: Add snapshot of QMI
This snapshot is taken as of msm-3.18 commit e70ad0cd (Promotion of
kernel.lnx.3.18-151201.)
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Kconfig | 16 | ||||
-rw-r--r-- | lib/Makefile | 2 | ||||
-rw-r--r-- | lib/qmi_encdec.c | 880 | ||||
-rw-r--r-- | lib/qmi_encdec_priv.h | 66 |
4 files changed, 964 insertions, 0 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index f0df318104e7..8b169b9793ec 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -529,4 +529,20 @@ config ARCH_HAS_PMEM_API config ARCH_HAS_MMIO_FLUSH bool +config QMI_ENCDEC + bool "QMI Encode/Decode Library" + help + Library to encode & decode QMI messages from within + the kernel. The kernel drivers encode the C structure into + QMI message wire format and then send it over a transport. + The kernel drivers receive the QMI message over a transport + and then decode it into a C structure. + +config QMI_ENCDEC_DEBUG + bool "QMI Encode/Decode Library Debug" + help + Kernel config option to enable debugging QMI Encode/Decode + library. This will log the information regarding the element + and message being encoded & decoded. + endmenu diff --git a/lib/Makefile b/lib/Makefile index 7f1de26613d2..b93d03acd1fd 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -208,3 +208,5 @@ quiet_cmd_build_OID_registry = GEN $@ clean-files += oid_registry_data.c obj-$(CONFIG_UCS2_STRING) += ucs2_string.o + +obj-$(CONFIG_QMI_ENCDEC) += qmi_encdec.o diff --git a/lib/qmi_encdec.c b/lib/qmi_encdec.c new file mode 100644 index 000000000000..72b506bececc --- /dev/null +++ b/lib/qmi_encdec.c @@ -0,0 +1,880 @@ +/* Copyright (c) 2012-2015, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/string.h> +#include <linux/qmi_encdec.h> + +#include "qmi_encdec_priv.h" + +#define TLV_LEN_SIZE sizeof(uint16_t) +#define TLV_TYPE_SIZE sizeof(uint8_t) +#define OPTIONAL_TLV_TYPE_START 0x10 + +#ifdef CONFIG_QMI_ENCDEC_DEBUG + +#define qmi_encdec_dump(prefix_str, buf, buf_len) do { \ + const u8 *ptr = buf; \ + int i, linelen, remaining = buf_len; \ + int rowsize = 16, groupsize = 1; \ + unsigned char linebuf[256]; \ + for (i = 0; i < buf_len; i += rowsize) { \ + linelen = min(remaining, rowsize); \ + remaining -= linelen; \ + hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, \ + linebuf, sizeof(linebuf), false); \ + pr_debug("%s: %s\n", prefix_str, linebuf); \ + } \ +} while (0) + +#define QMI_ENCODE_LOG_MSG(buf, buf_len) do { \ + qmi_encdec_dump("QMI_ENCODE_MSG", buf, buf_len); \ +} while (0) + +#define QMI_DECODE_LOG_MSG(buf, buf_len) do { \ + qmi_encdec_dump("QMI_DECODE_MSG", buf, buf_len); \ +} while (0) + +#define QMI_ENCODE_LOG_ELEM(level, elem_len, elem_size, buf) do { \ + pr_debug("QMI_ENCODE_ELEM lvl: %d, len: %d, size: %d\n", \ + level, elem_len, elem_size); \ + qmi_encdec_dump("QMI_ENCODE_ELEM", buf, (elem_len * elem_size)); \ +} while (0) + +#define QMI_DECODE_LOG_ELEM(level, elem_len, elem_size, buf) do { \ + pr_debug("QMI_DECODE_ELEM lvl: %d, len: %d, size: %d\n", \ + level, elem_len, elem_size); \ + qmi_encdec_dump("QMI_DECODE_ELEM", buf, (elem_len * elem_size)); \ +} while (0) + +#define QMI_ENCODE_LOG_TLV(tlv_type, tlv_len) do { \ + pr_debug("QMI_ENCODE_TLV type: %d, len: %d\n", tlv_type, tlv_len); \ +} while (0) + +#define QMI_DECODE_LOG_TLV(tlv_type, tlv_len) do { \ + pr_debug("QMI_DECODE_TLV type: %d, len: %d\n", tlv_type, tlv_len); \ +} while (0) + +#else + +#define QMI_ENCODE_LOG_MSG(buf, buf_len) { } +#define QMI_DECODE_LOG_MSG(buf, buf_len) { } +#define QMI_ENCODE_LOG_ELEM(level, elem_len, elem_size, buf) { } +#define QMI_DECODE_LOG_ELEM(level, elem_len, elem_size, buf) { } +#define QMI_ENCODE_LOG_TLV(tlv_type, tlv_len) { } +#define QMI_DECODE_LOG_TLV(tlv_type, tlv_len) { } + +#endif + +static int _qmi_kernel_encode(struct elem_info *ei_array, + void *out_buf, void *in_c_struct, + uint32_t out_buf_len, int enc_level); + +static int _qmi_kernel_decode(struct elem_info *ei_array, + void *out_c_struct, + void *in_buf, uint32_t in_buf_len, + int dec_level); +static struct elem_info *skip_to_next_elem(struct elem_info *ei_array, + int level); + +/** + * qmi_calc_max_msg_len() - Calculate the maximum length of a QMI message + * @ei_array: Struct info array describing the structure. + * @level: Level to identify the depth of the nested structures. + * + * @return: expected maximum length of the QMI message or 0 on failure. + */ +static int qmi_calc_max_msg_len(struct elem_info *ei_array, + int level) +{ + int max_msg_len = 0; + struct elem_info *temp_ei; + + if (!ei_array) + return max_msg_len; + + for (temp_ei = ei_array; temp_ei->data_type != QMI_EOTI; temp_ei++) { + /* Flag to identify the optional element is not encoded */ + if (temp_ei->data_type == QMI_OPT_FLAG) + continue; + + if (temp_ei->data_type == QMI_DATA_LEN) { + max_msg_len += (temp_ei->elem_size == sizeof(uint8_t) ? + sizeof(uint8_t) : sizeof(uint16_t)); + continue; + } else if (temp_ei->data_type == QMI_STRUCT) { + max_msg_len += (temp_ei->elem_len * + qmi_calc_max_msg_len(temp_ei->ei_array, + (level + 1))); + } else if (temp_ei->data_type == QMI_STRING) { + if (level > 1) + max_msg_len += temp_ei->elem_len <= U8_MAX ? + sizeof(uint8_t) : sizeof(uint16_t); + max_msg_len += temp_ei->elem_len * temp_ei->elem_size; + } else { + max_msg_len += (temp_ei->elem_len * temp_ei->elem_size); + } + + /* + * Type & Length info. not prepended for elements in the + * nested structure. + */ + if (level == 1) + max_msg_len += (TLV_TYPE_SIZE + TLV_LEN_SIZE); + } + return max_msg_len; +} + +/** + * qmi_calc_min_msg_len() - Calculate the minimum length of a QMI message + * @ei_array: Struct info array describing the structure. + * @level: Level to identify the depth of the nested structures. + * + * @return: expected minimum length of the QMI message or 0 on failure. + */ +static int qmi_calc_min_msg_len(struct elem_info *ei_array, + int level) +{ + int min_msg_len = 0; + struct elem_info *temp_ei = ei_array; + + if (!ei_array) + return min_msg_len; + + while (temp_ei->data_type != QMI_EOTI) { + /* Optional elements do not count in minimum length */ + if (temp_ei->data_type == QMI_OPT_FLAG) { + temp_ei = skip_to_next_elem(temp_ei, level); + continue; + } + + if (temp_ei->data_type == QMI_DATA_LEN) { + min_msg_len += (temp_ei->elem_size == sizeof(uint8_t) ? + sizeof(uint8_t) : sizeof(uint16_t)); + temp_ei++; + continue; + } else if (temp_ei->data_type == QMI_STRUCT) { + min_msg_len += qmi_calc_min_msg_len(temp_ei->ei_array, + (level + 1)); + temp_ei++; + } else if (temp_ei->data_type == QMI_STRING) { + if (level > 1) + min_msg_len += temp_ei->elem_len <= U8_MAX ? + sizeof(uint8_t) : sizeof(uint16_t); + min_msg_len += temp_ei->elem_len * temp_ei->elem_size; + temp_ei++; + } else { + min_msg_len += (temp_ei->elem_len * temp_ei->elem_size); + temp_ei++; + } + + /* + * Type & Length info. not prepended for elements in the + * nested structure. + */ + if (level == 1) + min_msg_len += (TLV_TYPE_SIZE + TLV_LEN_SIZE); + } + return min_msg_len; +} + +/** + * qmi_verify_max_msg_len() - Verify the maximum length of a QMI message + * @desc: Pointer to structure descriptor. + * + * @return: true if the maximum message length embedded in structure + * descriptor matches the calculated value, else false. + */ +bool qmi_verify_max_msg_len(struct msg_desc *desc) +{ + int calc_max_msg_len; + + if (!desc) + return false; + + calc_max_msg_len = qmi_calc_max_msg_len(desc->ei_array, 1); + if (calc_max_msg_len != desc->max_msg_len) { + pr_err("%s: Calc. len %d != Passed len %d\n", + __func__, calc_max_msg_len, desc->max_msg_len); + return false; + } + return true; +} + +/** + * qmi_kernel_encode() - Encode to QMI message wire format + * @desc: Pointer to structure descriptor. + * @out_buf: Buffer to hold the encoded QMI message. + * @out_buf_len: Length of the out buffer. + * @in_c_struct: C Structure to be encoded. + * + * @return: size of encoded message on success, < 0 for error. + */ +int qmi_kernel_encode(struct msg_desc *desc, + void *out_buf, uint32_t out_buf_len, + void *in_c_struct) +{ + int enc_level = 1; + int ret, calc_max_msg_len, calc_min_msg_len; + + if (!desc) + return -EINVAL; + + /* Check the possibility of a zero length QMI message */ + if (!in_c_struct) { + calc_min_msg_len = qmi_calc_min_msg_len(desc->ei_array, 1); + if (calc_min_msg_len) { + pr_err("%s: Calc. len %d != 0, but NULL in_c_struct\n", + __func__, calc_min_msg_len); + return -EINVAL; + } else { + return 0; + } + } + + /* + * Not a zero-length message. Ensure the output buffer and + * element information array are not NULL. + */ + if (!out_buf || !desc->ei_array) + return -EINVAL; + + if (desc->max_msg_len < out_buf_len) + return -ETOOSMALL; + + ret = _qmi_kernel_encode(desc->ei_array, out_buf, + in_c_struct, out_buf_len, enc_level); + if (ret == -ETOOSMALL) { + calc_max_msg_len = qmi_calc_max_msg_len(desc->ei_array, 1); + pr_err("%s: Calc. len %d != Out buf len %d\n", + __func__, calc_max_msg_len, out_buf_len); + } + return ret; +} +EXPORT_SYMBOL(qmi_kernel_encode); + +/** + * qmi_encode_basic_elem() - Encodes elements of basic/primary data type + * @buf_dst: Buffer to store the encoded information. + * @buf_src: Buffer containing the elements to be encoded. + * @elem_len: Number of elements, in the buf_src, to be encoded. + * @elem_size: Size of a single instance of the element to be encoded. + * + * @return: number of bytes of encoded information. + * + * This function encodes the "elem_len" number of data elements, each of + * size "elem_size" bytes from the source buffer "buf_src" and stores the + * encoded information in the destination buffer "buf_dst". The elements are + * of primary data type which include uint8_t - uint64_t or similar. This + * function returns the number of bytes of encoded information. + */ +static int qmi_encode_basic_elem(void *buf_dst, void *buf_src, + uint32_t elem_len, uint32_t elem_size) +{ + uint32_t i, rc = 0; + + for (i = 0; i < elem_len; i++) { + QMI_ENCDEC_ENCODE_N_BYTES(buf_dst, buf_src, elem_size); + rc += elem_size; + } + + return rc; +} + +/** + * qmi_encode_struct_elem() - Encodes elements of struct data type + * @ei_array: Struct info array descibing the struct element. + * @buf_dst: Buffer to store the encoded information. + * @buf_src: Buffer containing the elements to be encoded. + * @elem_len: Number of elements, in the buf_src, to be encoded. + * @out_buf_len: Available space in the encode buffer. + * @enc_level: Depth of the nested structure from the main structure. + * + * @return: Mumber of bytes of encoded information, on success. + * < 0 on error. + * + * This function encodes the "elem_len" number of struct elements, each of + * size "ei_array->elem_size" bytes from the source buffer "buf_src" and + * stores the encoded information in the destination buffer "buf_dst". The + * elements are of struct data type which includes any C structure. This + * function returns the number of bytes of encoded information. + */ +static int qmi_encode_struct_elem(struct elem_info *ei_array, + void *buf_dst, void *buf_src, + uint32_t elem_len, uint32_t out_buf_len, + int enc_level) +{ + int i, rc, encoded_bytes = 0; + struct elem_info *temp_ei = ei_array; + + for (i = 0; i < elem_len; i++) { + rc = _qmi_kernel_encode(temp_ei->ei_array, buf_dst, buf_src, + (out_buf_len - encoded_bytes), + enc_level); + if (rc < 0) { + pr_err("%s: STRUCT Encode failure\n", __func__); + return rc; + } + buf_dst = buf_dst + rc; + buf_src = buf_src + temp_ei->elem_size; + encoded_bytes += rc; + } + + return encoded_bytes; +} + +/** + * qmi_encode_string_elem() - Encodes elements of string data type + * @ei_array: Struct info array descibing the string element. + * @buf_dst: Buffer to store the encoded information. + * @buf_src: Buffer containing the elements to be encoded. + * @out_buf_len: Available space in the encode buffer. + * @enc_level: Depth of the string element from the main structure. + * + * @return: Mumber of bytes of encoded information, on success. + * < 0 on error. + * + * This function encodes a string element of maximum length "ei_array->elem_len" + * bytes from the source buffer "buf_src" and stores the encoded information in + * the destination buffer "buf_dst". This function returns the number of bytes + * of encoded information. + */ +static int qmi_encode_string_elem(struct elem_info *ei_array, + void *buf_dst, void *buf_src, + uint32_t out_buf_len, int enc_level) +{ + int rc; + int encoded_bytes = 0; + struct elem_info *temp_ei = ei_array; + uint32_t string_len = 0; + uint32_t string_len_sz = 0; + + string_len = strlen(buf_src); + string_len_sz = temp_ei->elem_len <= U8_MAX ? + sizeof(uint8_t) : sizeof(uint16_t); + if (string_len > temp_ei->elem_len) { + pr_err("%s: String to be encoded is longer - %d > %d\n", + __func__, string_len, temp_ei->elem_len); + return -EINVAL; + } + + if (enc_level == 1) { + if (string_len + TLV_LEN_SIZE + TLV_TYPE_SIZE > + out_buf_len) { + pr_err("%s: Output len %d > Out Buf len %d\n", + __func__, string_len, out_buf_len); + return -ETOOSMALL; + } + } else { + if (string_len + string_len_sz > out_buf_len) { + pr_err("%s: Output len %d > Out Buf len %d\n", + __func__, string_len, out_buf_len); + return -ETOOSMALL; + } + rc = qmi_encode_basic_elem(buf_dst, &string_len, + 1, string_len_sz); + encoded_bytes += rc; + } + + rc = qmi_encode_basic_elem(buf_dst + encoded_bytes, buf_src, + string_len, temp_ei->elem_size); + encoded_bytes += rc; + QMI_ENCODE_LOG_ELEM(enc_level, string_len, temp_ei->elem_size, buf_src); + return encoded_bytes; +} + +/** + * skip_to_next_elem() - Skip to next element in the structure to be encoded + * @ei_array: Struct info describing the element to be skipped. + * @level: Depth level of encoding/decoding to identify nested structures. + * + * @return: Struct info of the next element that can be encoded. + * + * This function is used while encoding optional elements. If the flag + * corresponding to an optional element is not set, then encoding the + * optional element can be skipped. This function can be used to perform + * that operation. + */ +static struct elem_info *skip_to_next_elem(struct elem_info *ei_array, + int level) +{ + struct elem_info *temp_ei = ei_array; + uint8_t tlv_type; + + if (level > 1) { + temp_ei = temp_ei + 1; + } else { + do { + tlv_type = temp_ei->tlv_type; + temp_ei = temp_ei + 1; + } while (tlv_type == temp_ei->tlv_type); + } + + return temp_ei; +} + +/** + * _qmi_kernel_encode() - Core Encode Function + * @ei_array: Struct info array describing the structure to be encoded. + * @out_buf: Buffer to hold the encoded QMI message. + * @in_c_struct: Pointer to the C structure to be encoded. + * @out_buf_len: Available space in the encode buffer. + * @enc_level: Encode level to indicate the depth of the nested structure, + * within the main structure, being encoded. + * + * @return: Number of bytes of encoded information, on success. + * < 0 on error. + */ +static int _qmi_kernel_encode(struct elem_info *ei_array, + void *out_buf, void *in_c_struct, + uint32_t out_buf_len, int enc_level) +{ + struct elem_info *temp_ei = ei_array; + uint8_t opt_flag_value = 0; + uint32_t data_len_value = 0, data_len_sz; + uint8_t *buf_dst = (uint8_t *)out_buf; + uint8_t *tlv_pointer; + uint32_t tlv_len; + uint8_t tlv_type; + uint32_t encoded_bytes = 0; + void *buf_src; + int encode_tlv = 0; + int rc; + + tlv_pointer = buf_dst; + tlv_len = 0; + if (enc_level == 1) + buf_dst = buf_dst + (TLV_LEN_SIZE + TLV_TYPE_SIZE); + + while (temp_ei->data_type != QMI_EOTI) { + buf_src = in_c_struct + temp_ei->offset; + tlv_type = temp_ei->tlv_type; + + if (temp_ei->is_array == NO_ARRAY) { + data_len_value = 1; + } else if (temp_ei->is_array == STATIC_ARRAY) { + data_len_value = temp_ei->elem_len; + } else if (data_len_value <= 0 || + temp_ei->elem_len < data_len_value) { + pr_err("%s: Invalid data length\n", __func__); + return -EINVAL; + } + + switch (temp_ei->data_type) { + case QMI_OPT_FLAG: + rc = qmi_encode_basic_elem(&opt_flag_value, buf_src, + 1, sizeof(uint8_t)); + if (opt_flag_value) + temp_ei = temp_ei + 1; + else + temp_ei = skip_to_next_elem(temp_ei, enc_level); + break; + + case QMI_DATA_LEN: + memcpy(&data_len_value, buf_src, temp_ei->elem_size); + data_len_sz = temp_ei->elem_size == sizeof(uint8_t) ? + sizeof(uint8_t) : sizeof(uint16_t); + /* Check to avoid out of range buffer access */ + if ((data_len_sz + encoded_bytes + TLV_LEN_SIZE + + TLV_TYPE_SIZE) > out_buf_len) { + pr_err("%s: Too Small Buffer @DATA_LEN\n", + __func__); + return -ETOOSMALL; + } + rc = qmi_encode_basic_elem(buf_dst, &data_len_value, + 1, data_len_sz); + UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst, + encoded_bytes, tlv_len, encode_tlv, rc); + if (!data_len_value) + temp_ei = skip_to_next_elem(temp_ei, enc_level); + else + encode_tlv = 0; + break; + + case QMI_UNSIGNED_1_BYTE: + case QMI_UNSIGNED_2_BYTE: + case QMI_UNSIGNED_4_BYTE: + case QMI_UNSIGNED_8_BYTE: + case QMI_SIGNED_2_BYTE_ENUM: + case QMI_SIGNED_4_BYTE_ENUM: + /* Check to avoid out of range buffer access */ + if (((data_len_value * temp_ei->elem_size) + + encoded_bytes + TLV_LEN_SIZE + TLV_TYPE_SIZE) > + out_buf_len) { + pr_err("%s: Too Small Buffer @data_type:%d\n", + __func__, temp_ei->data_type); + return -ETOOSMALL; + } + rc = qmi_encode_basic_elem(buf_dst, buf_src, + data_len_value, temp_ei->elem_size); + QMI_ENCODE_LOG_ELEM(enc_level, data_len_value, + temp_ei->elem_size, buf_src); + UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst, + encoded_bytes, tlv_len, encode_tlv, rc); + break; + + case QMI_STRUCT: + rc = qmi_encode_struct_elem(temp_ei, buf_dst, buf_src, + data_len_value, (out_buf_len - encoded_bytes), + (enc_level + 1)); + if (rc < 0) + return rc; + UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst, + encoded_bytes, tlv_len, encode_tlv, rc); + break; + + case QMI_STRING: + rc = qmi_encode_string_elem(temp_ei, buf_dst, buf_src, + out_buf_len - encoded_bytes, enc_level); + if (rc < 0) + return rc; + UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst, + encoded_bytes, tlv_len, encode_tlv, rc); + break; + default: + pr_err("%s: Unrecognized data type\n", __func__); + return -EINVAL; + + } + + if (encode_tlv && enc_level == 1) { + QMI_ENCDEC_ENCODE_TLV(tlv_type, tlv_len, tlv_pointer); + QMI_ENCODE_LOG_TLV(tlv_type, tlv_len); + encoded_bytes += (TLV_TYPE_SIZE + TLV_LEN_SIZE); + tlv_pointer = buf_dst; + tlv_len = 0; + buf_dst = buf_dst + TLV_LEN_SIZE + TLV_TYPE_SIZE; + encode_tlv = 0; + } + } + QMI_ENCODE_LOG_MSG(out_buf, encoded_bytes); + return encoded_bytes; +} + +/** + * qmi_kernel_decode() - Decode to C Structure format + * @desc: Pointer to structure descriptor. + * @out_c_struct: Buffer to hold the decoded C structure. + * @in_buf: Buffer containg the QMI message to be decoded. + * @in_buf_len: Length of the incoming QMI message. + * + * @return: 0 on success, < 0 on error. + */ +int qmi_kernel_decode(struct msg_desc *desc, void *out_c_struct, + void *in_buf, uint32_t in_buf_len) +{ + int dec_level = 1; + int rc = 0; + + if (!desc || !desc->ei_array) + return -EINVAL; + + if (!out_c_struct || !in_buf || !in_buf_len) + return -EINVAL; + + if (desc->max_msg_len < in_buf_len) + return -EINVAL; + + rc = _qmi_kernel_decode(desc->ei_array, out_c_struct, + in_buf, in_buf_len, dec_level); + if (rc < 0) + return rc; + else + return 0; +} +EXPORT_SYMBOL(qmi_kernel_decode); + +/** + * qmi_decode_basic_elem() - Decodes elements of basic/primary data type + * @buf_dst: Buffer to store the decoded element. + * @buf_src: Buffer containing the elements in QMI wire format. + * @elem_len: Number of elements to be decoded. + * @elem_size: Size of a single instance of the element to be decoded. + * + * @return: Total size of the decoded data elements, in bytes. + * + * This function decodes the "elem_len" number of elements in QMI wire format, + * each of size "elem_size" bytes from the source buffer "buf_src" and stores + * the decoded elements in the destination buffer "buf_dst". The elements are + * of primary data type which include uint8_t - uint64_t or similar. This + * function returns the number of bytes of decoded information. + */ +static int qmi_decode_basic_elem(void *buf_dst, void *buf_src, + uint32_t elem_len, uint32_t elem_size) +{ + uint32_t i, rc = 0; + + for (i = 0; i < elem_len; i++) { + QMI_ENCDEC_DECODE_N_BYTES(buf_dst, buf_src, elem_size); + rc += elem_size; + } + + return rc; +} + +/** + * qmi_decode_struct_elem() - Decodes elements of struct data type + * @ei_array: Struct info array descibing the struct element. + * @buf_dst: Buffer to store the decoded element. + * @buf_src: Buffer containing the elements in QMI wire format. + * @elem_len: Number of elements to be decoded. + * @tlv_len: Total size of the encoded inforation corresponding to + * this struct element. + * @dec_level: Depth of the nested structure from the main structure. + * + * @return: Total size of the decoded data elements, on success. + * < 0 on error. + * + * This function decodes the "elem_len" number of elements in QMI wire format, + * each of size "(tlv_len/elem_len)" bytes from the source buffer "buf_src" + * and stores the decoded elements in the destination buffer "buf_dst". The + * elements are of struct data type which includes any C structure. This + * function returns the number of bytes of decoded information. + */ +static int qmi_decode_struct_elem(struct elem_info *ei_array, void *buf_dst, + void *buf_src, uint32_t elem_len, + uint32_t tlv_len, int dec_level) +{ + int i, rc, decoded_bytes = 0; + struct elem_info *temp_ei = ei_array; + + for (i = 0; i < elem_len && decoded_bytes < tlv_len; i++) { + rc = _qmi_kernel_decode(temp_ei->ei_array, buf_dst, buf_src, + (tlv_len - decoded_bytes), dec_level); + if (rc < 0) + return rc; + buf_src = buf_src + rc; + buf_dst = buf_dst + temp_ei->elem_size; + decoded_bytes += rc; + } + + if ((dec_level <= 2 && decoded_bytes != tlv_len) || + (dec_level > 2 && (i < elem_len || decoded_bytes > tlv_len))) { + pr_err("%s: Fault in decoding: dl(%d), db(%d), tl(%d), i(%d), el(%d)\n", + __func__, dec_level, decoded_bytes, tlv_len, + i, elem_len); + return -EFAULT; + } + return decoded_bytes; +} + +/** + * qmi_decode_string_elem() - Decodes elements of string data type + * @ei_array: Struct info array descibing the string element. + * @buf_dst: Buffer to store the decoded element. + * @buf_src: Buffer containing the elements in QMI wire format. + * @tlv_len: Total size of the encoded inforation corresponding to + * this string element. + * @dec_level: Depth of the string element from the main structure. + * + * @return: Total size of the decoded data elements, on success. + * < 0 on error. + * + * This function decodes the string element of maximum length + * "ei_array->elem_len" from the source buffer "buf_src" and puts it into + * the destination buffer "buf_dst". This function returns number of bytes + * decoded from the input buffer. + */ +static int qmi_decode_string_elem(struct elem_info *ei_array, void *buf_dst, + void *buf_src, uint32_t tlv_len, + int dec_level) +{ + int rc; + int decoded_bytes = 0; + uint32_t string_len = 0; + uint32_t string_len_sz = 0; + struct elem_info *temp_ei = ei_array; + + if (dec_level == 1) { + string_len = tlv_len; + } else { + string_len_sz = temp_ei->elem_len <= U8_MAX ? + sizeof(uint8_t) : sizeof(uint16_t); + rc = qmi_decode_basic_elem(&string_len, buf_src, + 1, string_len_sz); + decoded_bytes += rc; + } + + if (string_len > temp_ei->elem_len) { + pr_err("%s: String len %d > Max Len %d\n", + __func__, string_len, temp_ei->elem_len); + return -ETOOSMALL; + } else if (string_len > tlv_len) { + pr_err("%s: String len %d > Input Buffer Len %d\n", + __func__, string_len, tlv_len); + return -EFAULT; + } + + rc = qmi_decode_basic_elem(buf_dst, buf_src + decoded_bytes, + string_len, temp_ei->elem_size); + *((char *)buf_dst + string_len) = '\0'; + decoded_bytes += rc; + QMI_DECODE_LOG_ELEM(dec_level, string_len, temp_ei->elem_size, buf_dst); + return decoded_bytes; +} + +/** + * find_ei() - Find element info corresponding to TLV Type + * @ei_array: Struct info array of the message being decoded. + * @type: TLV Type of the element being searched. + * + * @return: Pointer to struct info, if found + * + * Every element that got encoded in the QMI message will have a type + * information associated with it. While decoding the QMI message, + * this function is used to find the struct info regarding the element + * that corresponds to the type being decoded. + */ +static struct elem_info *find_ei(struct elem_info *ei_array, + uint32_t type) +{ + struct elem_info *temp_ei = ei_array; + while (temp_ei->data_type != QMI_EOTI) { + if (temp_ei->tlv_type == (uint8_t)type) + return temp_ei; + temp_ei = temp_ei + 1; + } + return NULL; +} + +/** + * _qmi_kernel_decode() - Core Decode Function + * @ei_array: Struct info array describing the structure to be decoded. + * @out_c_struct: Buffer to hold the decoded C struct + * @in_buf: Buffer containing the QMI message to be decoded + * @in_buf_len: Length of the QMI message to be decoded + * @dec_level: Decode level to indicate the depth of the nested structure, + * within the main structure, being decoded + * + * @return: Number of bytes of decoded information, on success + * < 0 on error. + */ +static int _qmi_kernel_decode(struct elem_info *ei_array, + void *out_c_struct, + void *in_buf, uint32_t in_buf_len, + int dec_level) +{ + struct elem_info *temp_ei = ei_array; + uint8_t opt_flag_value = 1; + uint32_t data_len_value = 0, data_len_sz = 0; + uint8_t *buf_dst = out_c_struct; + uint8_t *tlv_pointer; + uint32_t tlv_len = 0; + uint32_t tlv_type; + uint32_t decoded_bytes = 0; + void *buf_src = in_buf; + int rc; + + QMI_DECODE_LOG_MSG(in_buf, in_buf_len); + while (decoded_bytes < in_buf_len) { + if (dec_level >= 2 && temp_ei->data_type == QMI_EOTI) + return decoded_bytes; + + if (dec_level == 1) { + tlv_pointer = buf_src; + QMI_ENCDEC_DECODE_TLV(&tlv_type, + &tlv_len, tlv_pointer); + QMI_DECODE_LOG_TLV(tlv_type, tlv_len); + buf_src += (TLV_TYPE_SIZE + TLV_LEN_SIZE); + decoded_bytes += (TLV_TYPE_SIZE + TLV_LEN_SIZE); + temp_ei = find_ei(ei_array, tlv_type); + if (!temp_ei && (tlv_type < OPTIONAL_TLV_TYPE_START)) { + pr_err("%s: Inval element info\n", __func__); + return -EINVAL; + } else if (!temp_ei) { + UPDATE_DECODE_VARIABLES(buf_src, + decoded_bytes, tlv_len); + continue; + } + } else { + /* + * No length information for elements in nested + * structures. So use remaining decodable buffer space. + */ + tlv_len = in_buf_len - decoded_bytes; + } + + buf_dst = out_c_struct + temp_ei->offset; + if (temp_ei->data_type == QMI_OPT_FLAG) { + memcpy(buf_dst, &opt_flag_value, sizeof(uint8_t)); + temp_ei = temp_ei + 1; + buf_dst = out_c_struct + temp_ei->offset; + } + + if (temp_ei->data_type == QMI_DATA_LEN) { + data_len_sz = temp_ei->elem_size == sizeof(uint8_t) ? + sizeof(uint8_t) : sizeof(uint16_t); + rc = qmi_decode_basic_elem(&data_len_value, buf_src, + 1, data_len_sz); + memcpy(buf_dst, &data_len_value, sizeof(uint32_t)); + temp_ei = temp_ei + 1; + buf_dst = out_c_struct + temp_ei->offset; + tlv_len -= data_len_sz; + UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc); + } + + if (temp_ei->is_array == NO_ARRAY) { + data_len_value = 1; + } else if (temp_ei->is_array == STATIC_ARRAY) { + data_len_value = temp_ei->elem_len; + } else if (data_len_value > temp_ei->elem_len) { + pr_err("%s: Data len %d > max spec %d\n", + __func__, data_len_value, temp_ei->elem_len); + return -ETOOSMALL; + } + + switch (temp_ei->data_type) { + case QMI_UNSIGNED_1_BYTE: + case QMI_UNSIGNED_2_BYTE: + case QMI_UNSIGNED_4_BYTE: + case QMI_UNSIGNED_8_BYTE: + case QMI_SIGNED_2_BYTE_ENUM: + case QMI_SIGNED_4_BYTE_ENUM: + rc = qmi_decode_basic_elem(buf_dst, buf_src, + data_len_value, temp_ei->elem_size); + QMI_DECODE_LOG_ELEM(dec_level, data_len_value, + temp_ei->elem_size, buf_dst); + UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc); + break; + + case QMI_STRUCT: + rc = qmi_decode_struct_elem(temp_ei, buf_dst, buf_src, + data_len_value, tlv_len, (dec_level + 1)); + if (rc < 0) + return rc; + UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc); + break; + + case QMI_STRING: + rc = qmi_decode_string_elem(temp_ei, buf_dst, buf_src, + tlv_len, dec_level); + if (rc < 0) + return rc; + UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc); + break; + + default: + pr_err("%s: Unrecognized data type\n", __func__); + return -EINVAL; + } + temp_ei = temp_ei + 1; + } + return decoded_bytes; +} +MODULE_DESCRIPTION("QMI kernel enc/dec"); +MODULE_LICENSE("GPL v2"); diff --git a/lib/qmi_encdec_priv.h b/lib/qmi_encdec_priv.h new file mode 100644 index 000000000000..97fe45b9d97a --- /dev/null +++ b/lib/qmi_encdec_priv.h @@ -0,0 +1,66 @@ +/* Copyright (c) 2012, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _QMI_ENCDEC_PRIV_H_ +#define _QMI_ENCDEC_PRIV_H_ + +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/mm.h> +#include <linux/list.h> +#include <linux/socket.h> +#include <linux/gfp.h> +#include <linux/qmi_encdec.h> + +#define QMI_ENCDEC_ENCODE_TLV(type, length, p_dst) do { \ + *p_dst++ = type; \ + *p_dst++ = ((uint8_t)((length) & 0xFF)); \ + *p_dst++ = ((uint8_t)(((length) >> 8) & 0xFF)); \ +} while (0) + +#define QMI_ENCDEC_DECODE_TLV(p_type, p_length, p_src) do { \ + *p_type = (uint8_t)*p_src++; \ + *p_length = (uint8_t)*p_src++; \ + *p_length |= ((uint8_t)*p_src) << 8; \ +} while (0) + +#define QMI_ENCDEC_ENCODE_N_BYTES(p_dst, p_src, size) \ +do { \ + memcpy(p_dst, p_src, size); \ + p_dst = (uint8_t *)p_dst + size; \ + p_src = (uint8_t *)p_src + size; \ +} while (0) + +#define QMI_ENCDEC_DECODE_N_BYTES(p_dst, p_src, size) \ +do { \ + memcpy(p_dst, p_src, size); \ + p_dst = (uint8_t *)p_dst + size; \ + p_src = (uint8_t *)p_src + size; \ +} while (0) + +#define UPDATE_ENCODE_VARIABLES(temp_si, buf_dst, \ + encoded_bytes, tlv_len, encode_tlv, rc) \ +do { \ + buf_dst = (uint8_t *)buf_dst + rc; \ + encoded_bytes += rc; \ + tlv_len += rc; \ + temp_si = temp_si + 1; \ + encode_tlv = 1; \ +} while (0) + +#define UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc) \ +do { \ + buf_src = (uint8_t *)buf_src + rc; \ + decoded_bytes += rc; \ +} while (0) + +#endif |