/* * Copyright © Stéphane Raimbault * * SPDX-License-Identifier: BSD-3-Clause */ #include #include #include #include #include #include #include "unit-test.h" const int EXCEPTION_RC = 2; enum { TCP, TCP_PI, RTU }; int test_server(modbus_t *ctx, int use_backend); int send_crafted_request(modbus_t *ctx, int function, uint8_t *req, int req_size, uint16_t max_value, uint16_t bytes, int backend_length, int backend_offset); int equal_dword(uint16_t *tab_reg, const uint32_t value); int is_memory_equal(const void *s1, const void *s2, size_t size); #define BUG_REPORT(_cond, _format, _args...) \ printf("\nLine %d: assertion error for '%s': " _format "\n", __LINE__, #_cond, ##_args) #define ASSERT_TRUE(_cond, _format, __args...) \ { \ if (_cond) { \ printf("OK\n"); \ } else { \ BUG_REPORT(_cond, _format, ##__args); \ goto close; \ } \ }; int is_memory_equal(const void *s1, const void *s2, size_t size) { return (memcmp(s1, s2, size) == 0); } int equal_dword(uint16_t *tab_reg, const uint32_t value) { return ((tab_reg[0] == (value >> 16)) && (tab_reg[1] == (value & 0xFFFF))); } int main(int argc, char *argv[]) { /* Length of report slave ID response slave ID + ON/OFF + 'LMB' + version */ const int NB_REPORT_SLAVE_ID = 2 + 3 + strlen(LIBMODBUS_VERSION_STRING); uint8_t *tab_rp_bits = NULL; uint16_t *tab_rp_registers = NULL; uint16_t *tab_rp_registers_bad = NULL; modbus_t *ctx = NULL; int i; uint8_t value; int nb_points; int rc; float real; uint32_t old_response_to_sec; uint32_t old_response_to_usec; uint32_t new_response_to_sec; uint32_t new_response_to_usec; uint32_t old_byte_to_sec; uint32_t old_byte_to_usec; int use_backend; int success = FALSE; int old_slave; char *ip_or_device; if (argc > 1) { if (strcmp(argv[1], "tcp") == 0) { use_backend = TCP; } else if (strcmp(argv[1], "tcppi") == 0) { use_backend = TCP_PI; } else if (strcmp(argv[1], "rtu") == 0) { use_backend = RTU; } else { printf("Modbus client for unit testing\n"); printf("Usage:\n %s [tcp|tcppi|rtu]\n", argv[0]); printf("Eg. tcp 127.0.0.1 or rtu /dev/ttyUSB1\n\n"); exit(1); } } else { /* By default */ use_backend = TCP; } if (argc > 2) { ip_or_device = argv[2]; } else { switch (use_backend) { case TCP: ip_or_device = "127.0.0.1"; break; case TCP_PI: ip_or_device = "::1"; break; case RTU: ip_or_device = "/dev/ttyUSB1"; break; default: break; } } if (use_backend == TCP) { ctx = modbus_new_tcp(ip_or_device, 1502); } else if (use_backend == TCP_PI) { ctx = modbus_new_tcp_pi(ip_or_device, "1502"); } else { ctx = modbus_new_rtu(ip_or_device, 115200, 'N', 8, 1); } if (ctx == NULL) { fprintf(stderr, "Unable to allocate libmodbus context\n"); return -1; } modbus_set_debug(ctx, TRUE); modbus_set_error_recovery( ctx, MODBUS_ERROR_RECOVERY_LINK | MODBUS_ERROR_RECOVERY_PROTOCOL); if (use_backend == RTU) { modbus_set_slave(ctx, SERVER_ID); } modbus_get_response_timeout(ctx, &old_response_to_sec, &old_response_to_usec); if (modbus_connect(ctx) == -1) { fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno)); modbus_free(ctx); return -1; } /* Allocate and initialize the memory to store the bits */ nb_points = (UT_BITS_NB > UT_INPUT_BITS_NB) ? UT_BITS_NB : UT_INPUT_BITS_NB; tab_rp_bits = (uint8_t *) malloc(nb_points * sizeof(uint8_t)); memset(tab_rp_bits, 0, nb_points * sizeof(uint8_t)); /* Allocate and initialize the memory to store the registers */ nb_points = (UT_REGISTERS_NB > UT_INPUT_REGISTERS_NB) ? UT_REGISTERS_NB : UT_INPUT_REGISTERS_NB; tab_rp_registers = (uint16_t *) malloc(nb_points * sizeof(uint16_t)); memset(tab_rp_registers, 0, nb_points * sizeof(uint16_t)); printf("** UNIT TESTING **\n"); printf("1/1 No response timeout modification on connect: "); modbus_get_response_timeout(ctx, &new_response_to_sec, &new_response_to_usec); ASSERT_TRUE(old_response_to_sec == new_response_to_sec && old_response_to_usec == new_response_to_usec, ""); printf("\nTEST WRITE/READ:\n"); /** COIL BITS **/ /* Single */ rc = modbus_write_bit(ctx, UT_BITS_ADDRESS, ON); printf("1/2 modbus_write_bit: "); ASSERT_TRUE(rc == 1, ""); rc = modbus_read_bits(ctx, UT_BITS_ADDRESS, 1, tab_rp_bits); printf("2/2 modbus_read_bits: "); ASSERT_TRUE(rc == 1, "FAILED (nb points %d)\n", rc); ASSERT_TRUE(tab_rp_bits[0] == ON, "FAILED (%0X != %0X)\n", tab_rp_bits[0], ON); /* End single */ /* Multiple bits */ { uint8_t tab_value[UT_BITS_NB]; modbus_set_bits_from_bytes(tab_value, 0, UT_BITS_NB, UT_BITS_TAB); rc = modbus_write_bits(ctx, UT_BITS_ADDRESS, UT_BITS_NB, tab_value); printf("1/2 modbus_write_bits: "); ASSERT_TRUE(rc == UT_BITS_NB, ""); } rc = modbus_read_bits(ctx, UT_BITS_ADDRESS, UT_BITS_NB, tab_rp_bits); printf("2/2 modbus_read_bits: "); ASSERT_TRUE(rc == UT_BITS_NB, "FAILED (nb points %d)\n", rc); i = 0; nb_points = UT_BITS_NB; while (nb_points > 0) { int nb_bits = (nb_points > 8) ? 8 : nb_points; value = modbus_get_byte_from_bits(tab_rp_bits, i * 8, nb_bits); ASSERT_TRUE( value == UT_BITS_TAB[i], "FAILED (%0X != %0X)\n", value, UT_BITS_TAB[i]); nb_points -= nb_bits; i++; } printf("OK\n"); /* End of multiple bits */ /** DISCRETE INPUTS **/ rc = modbus_read_input_bits(ctx, UT_INPUT_BITS_ADDRESS, UT_INPUT_BITS_NB, tab_rp_bits); printf("1/1 modbus_read_input_bits: "); ASSERT_TRUE(rc == UT_INPUT_BITS_NB, "FAILED (nb points %d)\n", rc); i = 0; nb_points = UT_INPUT_BITS_NB; while (nb_points > 0) { int nb_bits = (nb_points > 8) ? 8 : nb_points; value = modbus_get_byte_from_bits(tab_rp_bits, i * 8, nb_bits); ASSERT_TRUE(value == UT_INPUT_BITS_TAB[i], "FAILED (%0X != %0X)\n", value, UT_INPUT_BITS_TAB[i]); nb_points -= nb_bits; i++; } printf("OK\n"); /** HOLDING REGISTERS **/ /* Single register */ rc = modbus_write_register(ctx, UT_REGISTERS_ADDRESS, 0x1234); printf("1/2 modbus_write_register: "); ASSERT_TRUE(rc == 1, ""); rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS, 1, tab_rp_registers); printf("2/2 modbus_read_registers: "); ASSERT_TRUE(rc == 1, "FAILED (nb points %d)\n", rc); ASSERT_TRUE(tab_rp_registers[0] == 0x1234, "FAILED (%0X != %0X)\n", tab_rp_registers[0], 0x1234); /* End of single register */ /* Many registers */ rc = modbus_write_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB, UT_REGISTERS_TAB); printf("1/5 modbus_write_registers: "); ASSERT_TRUE(rc == UT_REGISTERS_NB, ""); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB, tab_rp_registers); printf("2/5 modbus_read_registers: "); ASSERT_TRUE(rc == UT_REGISTERS_NB, "FAILED (nb points %d)\n", rc); for (i = 0; i < UT_REGISTERS_NB; i++) { ASSERT_TRUE(tab_rp_registers[i] == UT_REGISTERS_TAB[i], "FAILED (%0X != %0X)\n", tab_rp_registers[i], UT_REGISTERS_TAB[i]); } rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS, 0, tab_rp_registers); printf("3/5 modbus_read_registers (0): "); ASSERT_TRUE(rc == -1, "FAILED (nb_points %d)\n", rc); nb_points = (UT_REGISTERS_NB > UT_INPUT_REGISTERS_NB) ? UT_REGISTERS_NB : UT_INPUT_REGISTERS_NB; memset(tab_rp_registers, 0, nb_points * sizeof(uint16_t)); /* Write registers to zero from tab_rp_registers and store read registers into tab_rp_registers. So the read registers must set to 0, except the first one because there is an offset of 1 register on write. */ rc = modbus_write_and_read_registers(ctx, UT_REGISTERS_ADDRESS + 1, UT_REGISTERS_NB - 1, tab_rp_registers, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB, tab_rp_registers); printf("4/5 modbus_write_and_read_registers: "); ASSERT_TRUE( rc == UT_REGISTERS_NB, "FAILED (nb points %d != %d)\n", rc, UT_REGISTERS_NB); ASSERT_TRUE(tab_rp_registers[0] == UT_REGISTERS_TAB[0], "FAILED (%0X != %0X)\n", tab_rp_registers[0], UT_REGISTERS_TAB[0]); for (i = 1; i < UT_REGISTERS_NB; i++) { ASSERT_TRUE( tab_rp_registers[i] == 0, "FAILED (%0X != %0X)\n", tab_rp_registers[i], 0); } /* End of many registers */ /** INPUT REGISTERS **/ rc = modbus_read_input_registers( ctx, UT_INPUT_REGISTERS_ADDRESS, UT_INPUT_REGISTERS_NB, tab_rp_registers); printf("1/1 modbus_read_input_registers: "); ASSERT_TRUE(rc == UT_INPUT_REGISTERS_NB, "FAILED (nb points %d)\n", rc); for (i = 0; i < UT_INPUT_REGISTERS_NB; i++) { ASSERT_TRUE(tab_rp_registers[i] == UT_INPUT_REGISTERS_TAB[i], "FAILED (%0X != %0X)\n", tab_rp_registers[i], UT_INPUT_REGISTERS_TAB[i]); } /* MASKS */ printf("1/1 Write mask: "); rc = modbus_write_register(ctx, UT_REGISTERS_ADDRESS, 0x12); rc = modbus_mask_write_register(ctx, UT_REGISTERS_ADDRESS, 0xF2, 0x25); ASSERT_TRUE(rc != -1, "FAILED (%x == -1)\n", rc); rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS, 1, tab_rp_registers); ASSERT_TRUE( tab_rp_registers[0] == 0x17, "FAILED (%0X != %0X)\n", tab_rp_registers[0], 0x17); printf("\nTEST FLOATS\n"); /** FLOAT **/ printf("1/4 Set/get float ABCD: "); modbus_set_float_abcd(UT_REAL, tab_rp_registers); ASSERT_TRUE(is_memory_equal(tab_rp_registers, UT_IREAL_ABCD_SET, 4), "FAILED Set float ABCD"); real = modbus_get_float_abcd(UT_IREAL_ABCD_GET); ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL); printf("2/4 Set/get float DCBA: "); modbus_set_float_dcba(UT_REAL, tab_rp_registers); ASSERT_TRUE(is_memory_equal(tab_rp_registers, UT_IREAL_DCBA_SET, 4), "FAILED Set float DCBA"); real = modbus_get_float_dcba(UT_IREAL_DCBA_GET); ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL); printf("3/4 Set/get float BADC: "); modbus_set_float_badc(UT_REAL, tab_rp_registers); ASSERT_TRUE(is_memory_equal(tab_rp_registers, UT_IREAL_BADC_SET, 4), "FAILED Set float BADC"); real = modbus_get_float_badc(UT_IREAL_BADC_GET); ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL); printf("4/4 Set/get float CDAB: "); modbus_set_float_cdab(UT_REAL, tab_rp_registers); ASSERT_TRUE(is_memory_equal(tab_rp_registers, UT_IREAL_CDAB_SET, 4), "FAILED Set float CDAB"); real = modbus_get_float_cdab(UT_IREAL_CDAB_GET); ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL); printf("\nAt this point, error messages doesn't mean the test has failed\n"); /** ILLEGAL DATA ADDRESS **/ printf("\nTEST ILLEGAL DATA ADDRESS:\n"); /* The mapping begins at the defined addresses and ends at address + * nb_points so these addresses are not valid. */ rc = modbus_read_bits(ctx, 0, 1, tab_rp_bits); printf("* modbus_read_bits (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_read_bits(ctx, UT_BITS_ADDRESS, UT_BITS_NB + 1, tab_rp_bits); printf("* modbus_read_bits (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_read_input_bits(ctx, 0, 1, tab_rp_bits); printf("* modbus_read_input_bits (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_read_input_bits( ctx, UT_INPUT_BITS_ADDRESS, UT_INPUT_BITS_NB + 1, tab_rp_bits); printf("* modbus_read_input_bits (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_read_registers(ctx, 0, 1, tab_rp_registers); printf("* modbus_read_registers (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB_MAX + 1, tab_rp_registers); printf("* modbus_read_registers (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_read_input_registers(ctx, 0, 1, tab_rp_registers); printf("* modbus_read_input_registers (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_read_input_registers( ctx, UT_INPUT_REGISTERS_ADDRESS, UT_INPUT_REGISTERS_NB + 1, tab_rp_registers); printf("* modbus_read_input_registers (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_bit(ctx, 0, ON); printf("* modbus_write_bit (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_bit(ctx, UT_BITS_ADDRESS + UT_BITS_NB, ON); printf("* modbus_write_bit (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_bits(ctx, 0, 1, tab_rp_bits); printf("* modbus_write_bits (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_bits(ctx, UT_BITS_ADDRESS + UT_BITS_NB, UT_BITS_NB, tab_rp_bits); printf("* modbus_write_bits (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_register(ctx, 0, tab_rp_registers[0]); printf("* modbus_write_register (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_register( ctx, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX, tab_rp_registers[0]); printf("* modbus_write_register (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_registers(ctx, 0, 1, tab_rp_registers); printf("* modbus_write_registers (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_registers(ctx, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX, UT_REGISTERS_NB, tab_rp_registers); printf("* modbus_write_registers (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_mask_write_register(ctx, 0, 0xF2, 0x25); printf("* modbus_mask_write_registers (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_mask_write_register( ctx, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX, 0xF2, 0x25); printf("* modbus_mask_write_registers (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_and_read_registers( ctx, 0, 1, tab_rp_registers, 0, 1, tab_rp_registers); printf("* modbus_write_and_read_registers (0): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); rc = modbus_write_and_read_registers(ctx, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX, UT_REGISTERS_NB, tab_rp_registers, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX, UT_REGISTERS_NB, tab_rp_registers); printf("* modbus_write_and_read_registers (max): "); ASSERT_TRUE(rc == -1 && errno == EMBXILADD, ""); /** TOO MANY DATA **/ printf("\nTEST TOO MANY DATA ERROR:\n"); rc = modbus_read_bits(ctx, UT_BITS_ADDRESS, MODBUS_MAX_READ_BITS + 1, tab_rp_bits); printf("* modbus_read_bits: "); ASSERT_TRUE(rc == -1 && errno == EMBMDATA, ""); rc = modbus_read_input_bits( ctx, UT_INPUT_BITS_ADDRESS, MODBUS_MAX_READ_BITS + 1, tab_rp_bits); printf("* modbus_read_input_bits: "); ASSERT_TRUE(rc == -1 && errno == EMBMDATA, ""); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, MODBUS_MAX_READ_REGISTERS + 1, tab_rp_registers); printf("* modbus_read_registers: "); ASSERT_TRUE(rc == -1 && errno == EMBMDATA, ""); rc = modbus_read_input_registers( ctx, UT_INPUT_REGISTERS_ADDRESS, MODBUS_MAX_READ_REGISTERS + 1, tab_rp_registers); printf("* modbus_read_input_registers: "); ASSERT_TRUE(rc == -1 && errno == EMBMDATA, ""); rc = modbus_write_bits(ctx, UT_BITS_ADDRESS, MODBUS_MAX_WRITE_BITS + 1, tab_rp_bits); printf("* modbus_write_bits: "); ASSERT_TRUE(rc == -1 && errno == EMBMDATA, ""); rc = modbus_write_registers( ctx, UT_REGISTERS_ADDRESS, MODBUS_MAX_WRITE_REGISTERS + 1, tab_rp_registers); printf("* modbus_write_registers: "); ASSERT_TRUE(rc == -1 && errno == EMBMDATA, ""); /** SLAVE ADDRESS **/ old_slave = modbus_get_slave(ctx); printf("\nTEST SLAVE ADDRESS:\n"); printf("1/2 Not compliant slave address is refused: "); rc = modbus_set_slave(ctx, 248); ASSERT_TRUE(rc == -1, "Slave address of 248 shouldn't be allowed"); printf("2/2 Not compliant slave address is allowed: "); modbus_enable_quirks(ctx, MODBUS_QUIRK_MAX_SLAVE); rc = modbus_set_slave(ctx, 248); ASSERT_TRUE(rc == 0, "Not compliant slave address should have been accepted"); modbus_disable_quirks(ctx, MODBUS_QUIRK_MAX_SLAVE); rc = modbus_set_slave(ctx, old_slave); ASSERT_TRUE(rc == 0, "Unable to restore slave value") /** BAD USE OF REPLY FUNCTION **/ rc = modbus_write_bit(ctx, UT_BITS_ADDRESS_INVALID_REQUEST_LENGTH, ON); printf("* modbus_write_bit (triggers invalid reply): "); ASSERT_TRUE(rc == -1 && errno == EMBXILVAL, ""); rc = modbus_write_register(ctx, UT_REGISTERS_ADDRESS_SPECIAL, 0x42); printf("* modbus_write_register (triggers invalid reply): "); ASSERT_TRUE(rc == -1 && errno == EMBXILVAL, ""); /** SLAVE REPLY **/ printf("\nTEST SLAVE REPLY:\n"); modbus_set_slave(ctx, INVALID_SERVER_ID); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB, tab_rp_registers); if (use_backend == RTU) { const int RAW_REQ_LENGTH = 6; uint8_t raw_req[] = {INVALID_SERVER_ID, 0x03, 0x00, 0x01, 0x01, 0x01}; /* Too many points */ uint8_t raw_invalid_req[] = {INVALID_SERVER_ID, 0x03, 0x00, 0x01, 0xFF, 0xFF}; const int RAW_RSP_LENGTH = 7; uint8_t raw_rsp[] = {INVALID_SERVER_ID, 0x03, 0x04, 0, 0, 0, 0}; uint8_t rsp[MODBUS_RTU_MAX_ADU_LENGTH]; /* No response in RTU mode */ printf("1-A/3 No response from slave %d: ", INVALID_SERVER_ID); ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, ""); /* The slave raises a timeout on a confirmation to ignore because if an * indication for another slave is received, a confirmation must follow */ /* Send a pair of indication/confirmation to the slave with a different * slave ID to simulate a communication on a RS485 bus. At first, the * slave will see the indication message then the confirmation, and it must * ignore both. */ modbus_send_raw_request(ctx, raw_req, RAW_REQ_LENGTH * sizeof(uint8_t)); modbus_send_raw_request(ctx, raw_rsp, RAW_RSP_LENGTH * sizeof(uint8_t)); rc = modbus_receive_confirmation(ctx, rsp); printf("1-B/3 No response from slave %d on indication/confirmation messages: ", INVALID_SERVER_ID); ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, ""); /* Send an INVALID request for another slave */ modbus_send_raw_request(ctx, raw_invalid_req, RAW_REQ_LENGTH * sizeof(uint8_t)); rc = modbus_receive_confirmation(ctx, rsp); printf("1-C/3 No response from slave %d with invalid request: ", INVALID_SERVER_ID); ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, ""); rc = modbus_set_slave(ctx, MODBUS_BROADCAST_ADDRESS); ASSERT_TRUE(rc == 0, "Invalid broadcast address"); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB, tab_rp_registers); printf("2/3 No reply after a broadcast query: "); ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, ""); } else { /* Response in TCP mode */ printf("1/3 Response from slave %d: ", INVALID_SERVER_ID); ASSERT_TRUE(rc == UT_REGISTERS_NB, ""); rc = modbus_set_slave(ctx, MODBUS_BROADCAST_ADDRESS); ASSERT_TRUE(rc == 0, "Invalid broacast address"); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB, tab_rp_registers); printf("2/3 Reply after a query with unit id == 0: "); ASSERT_TRUE(rc == UT_REGISTERS_NB, ""); } /* Restore slave */ modbus_set_slave(ctx, old_slave); printf("3/3 Response with an invalid TID or slave: "); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS_INVALID_TID_OR_SLAVE, 1, tab_rp_registers); ASSERT_TRUE(rc == -1, ""); printf("1/2 Report slave ID truncated: \n"); /* Set a marker to ensure limit is respected */ tab_rp_bits[NB_REPORT_SLAVE_ID - 1] = 42; rc = modbus_report_slave_id(ctx, NB_REPORT_SLAVE_ID - 1, tab_rp_bits); /* Return the size required (response size) but respects the defined limit */ ASSERT_TRUE(rc == NB_REPORT_SLAVE_ID && tab_rp_bits[NB_REPORT_SLAVE_ID - 1] == 42, "Return is rc %d (%d) and marker is %d (42)", rc, NB_REPORT_SLAVE_ID, tab_rp_bits[NB_REPORT_SLAVE_ID - 1]); printf("2/2 Report slave ID: \n"); /* tab_rp_bits is used to store bytes */ rc = modbus_report_slave_id(ctx, NB_REPORT_SLAVE_ID, tab_rp_bits); ASSERT_TRUE(rc == NB_REPORT_SLAVE_ID, ""); /* Slave ID is an arbitrary number for libmodbus */ ASSERT_TRUE(rc > 0, ""); /* Run status indicator is ON */ ASSERT_TRUE(rc > 1 && tab_rp_bits[1] == 0xFF, ""); /* Print additional data as string */ if (rc > 2) { printf("Additional data: "); for (i = 2; i < rc; i++) { printf("%c", tab_rp_bits[i]); } printf("\n"); } /* Save original timeout */ modbus_get_response_timeout(ctx, &old_response_to_sec, &old_response_to_usec); modbus_get_byte_timeout(ctx, &old_byte_to_sec, &old_byte_to_usec); rc = modbus_set_response_timeout(ctx, 0, 0); printf("1/6 Invalid response timeout (zero): "); ASSERT_TRUE(rc == -1 && errno == EINVAL, ""); rc = modbus_set_response_timeout(ctx, 0, 1000000); printf("2/6 Invalid response timeout (too large us): "); ASSERT_TRUE(rc == -1 && errno == EINVAL, ""); rc = modbus_set_byte_timeout(ctx, 0, 1000000); printf("3/6 Invalid byte timeout (too large us): "); ASSERT_TRUE(rc == -1 && errno == EINVAL, ""); modbus_set_response_timeout(ctx, 0, 1); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB, tab_rp_registers); printf("4/6 1us response timeout: "); if (rc == -1 && errno == ETIMEDOUT) { printf("OK\n"); } else { printf("FAILED (can fail on some platforms)\n"); } /* A wait and flush operation is done by the error recovery code of * libmodbus but after a sleep of current response timeout * so 0 can be too short! */ usleep(old_response_to_sec * 1000000 + old_response_to_usec); modbus_flush(ctx); /* Trigger a special behaviour on server to wait for 0.5 second before * replying whereas allowed timeout is 0.2 second */ modbus_set_response_timeout(ctx, 0, 200000); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS_SLEEP_500_MS, 1, tab_rp_registers); printf("5/6 Too short response timeout (0.2s < 0.5s): "); ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, ""); /* Wait for reply (0.2 + 0.4 > 0.5 s) and flush before continue */ usleep(400000); modbus_flush(ctx); modbus_set_response_timeout(ctx, 0, 600000); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS_SLEEP_500_MS, 1, tab_rp_registers); printf("6/6 Adequate response timeout (0.6s > 0.5s): "); ASSERT_TRUE(rc == 1, ""); /* Disable the byte timeout. The full response must be available in the 600ms interval */ modbus_set_byte_timeout(ctx, 0, 0); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS_SLEEP_500_MS, 1, tab_rp_registers); printf("7/7 Disable byte timeout: "); ASSERT_TRUE(rc == 1, ""); /* Restore original response timeout */ modbus_set_response_timeout(ctx, old_response_to_sec, old_response_to_usec); if (use_backend == TCP) { /* The test server is only able to test byte timeouts with the TCP * backend */ /* Timeout of 3ms between bytes */ modbus_set_byte_timeout(ctx, 0, 3000); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS_BYTE_SLEEP_5_MS, 1, tab_rp_registers); printf("1/2 Too small byte timeout (3ms < 5ms): "); ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, ""); /* Wait remaining bytes before flushing */ usleep(11 * 5000); modbus_flush(ctx); /* Timeout of 7ms between bytes */ modbus_set_byte_timeout(ctx, 0, 7000); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS_BYTE_SLEEP_5_MS, 1, tab_rp_registers); printf("2/2 Adapted byte timeout (7ms > 5ms): "); ASSERT_TRUE(rc == 1, ""); } /* Restore original byte timeout */ modbus_set_byte_timeout(ctx, old_byte_to_sec, old_byte_to_usec); /** BAD RESPONSE **/ printf("\nTEST BAD RESPONSE ERROR:\n"); /* Allocate only the required space */ tab_rp_registers_bad = (uint16_t *) malloc(UT_REGISTERS_NB_SPECIAL * sizeof(uint16_t)); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS, UT_REGISTERS_NB_SPECIAL, tab_rp_registers_bad); printf("* modbus_read_registers: "); ASSERT_TRUE(rc == -1 && errno == EMBBADDATA, ""); free(tab_rp_registers_bad); /** MANUAL EXCEPTION **/ printf("\nTEST MANUAL EXCEPTION:\n"); rc = modbus_read_registers( ctx, UT_REGISTERS_ADDRESS_SPECIAL, UT_REGISTERS_NB, tab_rp_registers); printf("* modbus_read_registers at special address: "); ASSERT_TRUE(rc == -1 && errno == EMBXSBUSY, ""); /** Run a few tests to challenge the server code **/ if (test_server(ctx, use_backend) == -1) { goto close; } modbus_close(ctx); modbus_free(ctx); ctx = NULL; /* Test init functions */ printf("\nTEST INVALID INITIALIZATION:\n"); ctx = modbus_new_rtu(NULL, 1, 'A', 0, 0); ASSERT_TRUE(ctx == NULL && errno == EINVAL, ""); ctx = modbus_new_rtu("/dev/dummy", 0, 'A', 0, 0); ASSERT_TRUE(ctx == NULL && errno == EINVAL, ""); printf("\nALL TESTS PASS WITH SUCCESS.\n"); success = TRUE; close: /* Free the memory */ free(tab_rp_bits); free(tab_rp_registers); /* Close the connection */ modbus_close(ctx); modbus_free(ctx); return (success) ? 0 : -1; } /* Send crafted requests to test server resilience and ensure proper exceptions are returned. */ int test_server(modbus_t *ctx, int use_backend) { int rc; int i; /* Read requests */ const int READ_RAW_REQ_LEN = 6; const int slave = (use_backend == RTU) ? SERVER_ID : MODBUS_TCP_SLAVE; uint8_t read_raw_req[] = {slave, /* function, address, 5 values */ MODBUS_FC_READ_HOLDING_REGISTERS, UT_REGISTERS_ADDRESS >> 8, UT_REGISTERS_ADDRESS & 0xFF, 0x0, 0x05}; /* Write and read registers request */ const int RW_RAW_REQ_LEN = 13; uint8_t rw_raw_req[] = {slave, /* function, addr to read, nb to read */ MODBUS_FC_WRITE_AND_READ_REGISTERS, /* Read */ UT_REGISTERS_ADDRESS >> 8, UT_REGISTERS_ADDRESS & 0xFF, (MODBUS_MAX_WR_READ_REGISTERS + 1) >> 8, (MODBUS_MAX_WR_READ_REGISTERS + 1) & 0xFF, /* Write */ 0, 0, 0, 1, /* Write byte count */ 1 * 2, /* One data to write... */ 0x12, 0x34}; const int WRITE_RAW_REQ_LEN = 13; uint8_t write_raw_req[] = {slave, /* function will be set in the loop */ MODBUS_FC_WRITE_MULTIPLE_REGISTERS, /* Address */ UT_REGISTERS_ADDRESS >> 8, UT_REGISTERS_ADDRESS & 0xFF, /* 3 values, 6 bytes */ 0x00, 0x03, 0x06, /* Dummy data to write */ 0x02, 0x2B, 0x00, 0x01, 0x00, 0x64}; const int INVALID_FC = 0x42; const int INVALID_FC_REQ_LEN = 6; uint8_t invalid_fc_raw_req[] = {slave, 0x42, 0x00, 0x00, 0x00, 0x00}; int req_length; uint8_t rsp[MODBUS_TCP_MAX_ADU_LENGTH]; int tab_read_function[] = {MODBUS_FC_READ_COILS, MODBUS_FC_READ_DISCRETE_INPUTS, MODBUS_FC_READ_HOLDING_REGISTERS, MODBUS_FC_READ_INPUT_REGISTERS}; int tab_read_nb_max[] = {MODBUS_MAX_READ_BITS + 1, MODBUS_MAX_READ_BITS + 1, MODBUS_MAX_READ_REGISTERS + 1, MODBUS_MAX_READ_REGISTERS + 1}; int backend_length; int backend_offset; if (use_backend == RTU) { backend_length = 3; backend_offset = 1; } else { backend_length = 7; backend_offset = 7; } printf("\nTEST RAW REQUESTS:\n"); uint32_t old_response_to_sec; uint32_t old_response_to_usec; /* This requests can generate flushes server side so we need a higher * response timeout than the server. The server uses the defined response * timeout to sleep before flushing. * The old timeouts are restored at the end. */ modbus_get_response_timeout(ctx, &old_response_to_sec, &old_response_to_usec); modbus_set_response_timeout(ctx, 0, 600000); int old_s = modbus_get_socket(ctx); modbus_set_socket(ctx, -1); rc = modbus_receive(ctx, rsp); modbus_set_socket(ctx, old_s); printf("* modbus_receive with invalid socket: "); ASSERT_TRUE(rc == -1, "FAILED (%d)\n", rc); req_length = modbus_send_raw_request(ctx, read_raw_req, READ_RAW_REQ_LEN); printf("* modbus_send_raw_request: "); ASSERT_TRUE(req_length == (backend_length + 5), "FAILED (%d)\n", req_length); printf("* modbus_receive_confirmation: "); rc = modbus_receive_confirmation(ctx, rsp); ASSERT_TRUE(rc == (backend_length + 12), "FAILED (%d)\n", rc); /* Try to read more values than a response could hold for all data types. */ for (i = 0; i < 4; i++) { rc = send_crafted_request(ctx, tab_read_function[i], read_raw_req, READ_RAW_REQ_LEN, tab_read_nb_max[i], 0, backend_length, backend_offset); if (rc == -1) goto close; } rc = send_crafted_request(ctx, MODBUS_FC_WRITE_AND_READ_REGISTERS, rw_raw_req, RW_RAW_REQ_LEN, MODBUS_MAX_WR_READ_REGISTERS + 1, 0, backend_length, backend_offset); if (rc == -1) goto close; rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_REGISTERS, write_raw_req, WRITE_RAW_REQ_LEN, MODBUS_MAX_WRITE_REGISTERS + 1, 6, backend_length, backend_offset); if (rc == -1) goto close; rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_COILS, write_raw_req, WRITE_RAW_REQ_LEN, MODBUS_MAX_WRITE_BITS + 1, 6, backend_length, backend_offset); if (rc == -1) goto close; /* Modbus write multiple registers with large number of values but a set a small number of bytes in requests (not nb * 2 as usual). */ rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_REGISTERS, write_raw_req, WRITE_RAW_REQ_LEN, MODBUS_MAX_WRITE_REGISTERS, 6, backend_length, backend_offset); if (rc == -1) goto close; rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_COILS, write_raw_req, WRITE_RAW_REQ_LEN, MODBUS_MAX_WRITE_BITS, 6, backend_length, backend_offset); if (rc == -1) goto close; /* Test invalid function code */ modbus_send_raw_request( ctx, invalid_fc_raw_req, INVALID_FC_REQ_LEN * sizeof(uint8_t)); rc = modbus_receive_confirmation(ctx, rsp); printf("Return an exception on unknown function code: "); ASSERT_TRUE(rc == (backend_length + EXCEPTION_RC) && rsp[backend_offset] == (0x80 + INVALID_FC), "") modbus_set_response_timeout(ctx, old_response_to_sec, old_response_to_usec); return 0; close: modbus_set_response_timeout(ctx, old_response_to_sec, old_response_to_usec); return -1; } int send_crafted_request(modbus_t *ctx, int function, uint8_t *req, int req_len, uint16_t max_value, uint16_t bytes, int backend_length, int backend_offset) { uint8_t rsp[MODBUS_TCP_MAX_ADU_LENGTH]; int j; for (j = 0; j < 2; j++) { int rc; req[1] = function; if (j == 0) { /* Try to read or write zero values on first iteration */ req[4] = 0x00; req[5] = 0x00; if (bytes) { /* Write query */ req[6] = 0x00; } } else { /* Try to read or write max values + 1 on second iteration */ req[4] = (max_value >> 8) & 0xFF; req[5] = max_value & 0xFF; if (bytes) { /* Write query (nb values * 2 to convert in bytes for registers) */ req[6] = bytes; } } modbus_send_raw_request(ctx, req, req_len * sizeof(uint8_t)); if (j == 0) { printf( "* try function 0x%X: %s 0 values: ", function, bytes ? "write" : "read"); } else { printf("* try function 0x%X: %s %d values: ", function, bytes ? "write" : "read", max_value); } rc = modbus_receive_confirmation(ctx, rsp); ASSERT_TRUE(rc == (backend_length + EXCEPTION_RC) && rsp[backend_offset] == (0x80 + function) && rsp[backend_offset + 1] == MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, ""); } return 0; close: return -1; }