// Copyright 2015-2019 Espressif Systems (Shanghai) PTE LTD // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/unistd.h> #include <sys/fcntl.h> #include "esp_types.h" #include "esp_err.h" #include "esp_log.h" #include "pcap.h" static const char *PCAP_TAG = "pcap"; #define PCAP_CHECK(a, str, goto_tag, ...) \ do \ { \ if (!(a)) \ { \ ESP_LOGE(PCAP_TAG, "%s(%d): " str, __FUNCTION__, __LINE__, ##__VA_ARGS__); \ goto goto_tag; \ } \ } while (0) /** * @brief Pcap File Header * */ typedef struct { uint32_t magic; /*!< Magic Number */ uint16_t major; /*!< Major Version */ uint16_t minor; /*!< Minor Version */ uint32_t zone; /*!< Time Zone Offset */ uint32_t sigfigs; /*!< Timestamp Accuracy */ uint32_t snaplen; /*!< Max Length to Capture */ uint32_t link_type; /*!< Link Layer Type */ } pcap_file_header_t; /** * @brief Pcap Packet Header * */ typedef struct { uint32_t seconds; /*!< Number of seconds since January 1st, 1970, 00:00:00 GMT */ uint32_t microseconds; /*!< Number of microseconds when the packet was captured (offset from seconds) */ uint32_t capture_length; /*!< Number of bytes of captured data, no longer than packet_length */ uint32_t packet_length; /*!< Actual length of current packet */ } pcap_packet_header_t; /** * @brief Pcap Runtime Handle * */ typedef struct { FILE *file; /*!< File handle */ } pcap_runtime_t; esp_err_t pcap_capture_packet(pcap_handle_t handle, void *payload, uint32_t length, uint32_t seconds, uint32_t microseconds) { PCAP_CHECK(handle, "pcap handle is NULL", err); pcap_runtime_t *pcap_rt = (pcap_runtime_t *)handle; PCAP_CHECK(pcap_rt->file, "pcap file is NULL", err); size_t real_write = 0; pcap_packet_header_t header = { .seconds = seconds, .microseconds = microseconds, .capture_length = length, .packet_length = length }; real_write = fwrite(&header, sizeof(header), 1, pcap_rt->file); PCAP_CHECK(real_write == 1, "write packet header error", err); real_write = fwrite(payload, sizeof(uint8_t), length, pcap_rt->file); PCAP_CHECK(real_write == length, "write packet payload error", err); /* Flush content in the buffer into device */ fflush(pcap_rt->file); return ESP_OK; err: return ESP_FAIL; } esp_err_t pcap_deinit(pcap_handle_t handle) { PCAP_CHECK(handle, "pcap handle is NULL", err); pcap_runtime_t *pcap_rt = (pcap_runtime_t *)handle; PCAP_CHECK(pcap_rt->file, "pcap file is NULL", err); PCAP_CHECK(fclose(pcap_rt->file) == 0, "close pcap file failed", err); pcap_rt->file = NULL; free(pcap_rt); ESP_LOGD(PCAP_TAG, "pcap deinit OK"); return ESP_OK; err: ESP_LOGW(PCAP_TAG, "pcap deinit failed"); return ESP_FAIL; } esp_err_t pcap_init(pcap_config_t *config, pcap_handle_t *handle) { PCAP_CHECK(config, "config is NULL", err); PCAP_CHECK(handle, "pcap handle is NULL", err); pcap_runtime_t *pcap_rt = calloc(sizeof(pcap_runtime_t), 1); PCAP_CHECK(pcap_rt, "calloc pcap runtime failed", err); pcap_rt->file = config->fp; /* Write Pcap File header */ pcap_file_header_t header = { .magic = PCAP_MAGIC_BIG_ENDIAN, .major = PCAP_VERSION_MAJOR, .minor = PCAP_VERSION_MINOR, .zone = PCAP_TIME_ZONE_GMT, .sigfigs = 0, .snaplen = 0x40000, .link_type = config->link_type }; size_t real_write = fwrite(&header, sizeof(header), 1, pcap_rt->file); PCAP_CHECK(real_write == 1, "write pcap file header failed", err_write); /* Flush content in the buffer into device */ fflush(pcap_rt->file); *handle = (pcap_handle_t)pcap_rt; ESP_LOGD(PCAP_TAG, "pcap init OK"); return ESP_OK; /* Error Handling */ err_write: fclose(pcap_rt->file); pcap_rt->file = NULL; free(pcap_rt); err: ESP_LOGW(PCAP_TAG, "pcap init failed"); return ESP_FAIL; }