Kévin Redon has uploaded this change for review. ( https://gerrit.osmocom.org/9855
Change subject: sniffer: use ISR to store sniffed data in buffer, add ATR and PPS parsing, and PPS related FiDi update ...................................................................... sniffer: use ISR to store sniffed data in buffer, add ATR and PPS parsing, and PPS related FiDi update Change-Id: I4b38ce1d80e370fda6aa181e959ba3f1286bb922 --- M firmware/libcommon/source/sniffer.c 1 file changed, 363 insertions(+), 18 deletions(-) git pull ssh://gerrit.osmocom.org:29418/simtrace2 refs/changes/55/9855/1 diff --git a/firmware/libcommon/source/sniffer.c b/firmware/libcommon/source/sniffer.c index 987e3e5..c71c491 100644 --- a/firmware/libcommon/source/sniffer.c +++ b/firmware/libcommon/source/sniffer.c @@ -17,8 +17,10 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. * */ -/* This code implement the Sniffer mode to sniff the communication between a SIM card and a phone. +/* This code implement the Sniffer mode to sniff the communication between a SIM card (or any ISO 7816 smart card) and a phone (or any ISO 7816 card reader). * For historical reasons (i.e. SIMtrace hardware) the USART peripheral connected to the SIM card is used. + * TODO handle RST, PTS, and send data over USB + * TODO put common ISO7816-3 code is separate library (and combine clean with iso7816_4) */ #include "board.h" #include "simtrace.h" @@ -30,19 +32,22 @@ *------------------------------------------------------------------------------*/ #include <string.h> +#include "utils.h" +#include "iso7816_fidi.h" /*------------------------------------------------------------------------------ * Internal definitions *------------------------------------------------------------------------------*/ -/** Maximum ucSize in bytes of the smartcard answer to a command.*/ -#define MAX_ANSWER_SIZE 10 - -/*! Maximum Answer-To-Reset (ATR) size in bytes ucSize in bytes +/*! Maximum Answer-To-Reset (ATR) size in bytes * @note defined in ISO/IEC 7816-3:2006(E) section 8.2.1 as 32, on top the initial character TS of section 8.1 * @remark technical there is no size limitation since Yi present in T0,TDi will indicate if more interface bytes are present, including TDi+i */ #define MAX_ATR_SIZE 33 +/*! Maximum Protocol and Parameters Selection (PPS) size in bytes + * @note defined in ISO/IEC 7816-3:2006(E) section 9.2 + */ +#define MAX_PPS_SIZE 6 /*! ISO 7816-3 states relevant to the sniff mode */ enum iso7816_3_sniff_state { @@ -51,7 +56,9 @@ ISO7816_S_IN_ATR, /*!< while we are receiving the ATR */ ISO7816_S_WAIT_APDU, /*!< waiting for start of new APDU */ ISO7816_S_IN_APDU, /*!< inside a single APDU */ - ISO7816_S_IN_PTS, /*!< while we are inside the PTS / PSS */ + ISO7816_S_IN_PPS_REQ, /*!< while we are inside the PPS request */ + ISO7816_S_WAIT_PPS_RSP, /*!< waiting for start of the PPS response */ + ISO7816_S_IN_PPS_RSP, /*!< while we are inside the PPS request */ }; /*! Answer-To-Reset (ATR) sub-states of ISO7816_S_IN_ATR @@ -66,7 +73,18 @@ ATR_S_WAIT_TD, /*!< fourth sub-group interface byte */ ATR_S_WAIT_HIST, /*!< historical byte */ ATR_S_WAIT_TCK, /*!< check byte */ - ATR_S_DONE, /*!< to indicated all ATR bytes have been received */ +}; + +/*! Protocol and Parameters Selection (PPS) sub-states of ISO7816_S_IN_PTS_REQ/ISO7816_S_IN_PTS_RSP + * @note defined in ISO/IEC 7816-3:2006(E) section 9 + */ +enum pps_sniff_state { + PPS_S_WAIT_PPSS, /*!< initial byte */ + PPS_S_WAIT_PPS0, /*!< format byte */ + PPS_S_WAIT_PPS1, /*!< first parameter byte */ + PPS_S_WAIT_PPS2, /*!< second parameter byte */ + PPS_S_WAIT_PPS3, /*!< third parameter byte */ + PPS_S_WAIT_PCK, /*!< check byte */ }; /*------------------------------------------------------------------------------ @@ -77,36 +95,328 @@ * to support a second sniffer interface the code should be restructured to use handles. */ /* Pin configurations */ -/* Pin configuration to sniff communication (using USART connection card) */ +/*! Pin configuration to sniff communication (using USART connection card) */ static const Pin pins_sniff[] = { PINS_SIM_SNIFF }; +/*! Pin configuration to interconnect phone and card using the bus switch */ static const Pin pins_bus[] = { PINS_BUS_SNIFF }; +/*! Pin configuration to power the card by the phone */ static const Pin pins_power[] = { PINS_PWR_SNIFF }; +/*! Pin configuration for timer counter to measure ETU timing */ static const Pin pins_tc[] = { PINS_TC }; +/*! Pin configuration for card reset line */ +static const Pin pin_rst = PIN_SIM_RST_SNIFF; + /* USART related variables */ -/* USART peripheral used to sniff communication */ +/*! USART peripheral used to sniff communication */ static struct Usart_info sniff_usart = { .base = USART_SIM, .id = ID_USART_SIM, .state = USART_RCV, }; -/* Ring buffer to store sniffer communication data */ +/*! Ring buffer to store sniffer communication data */ static struct ringbuf sniff_buffer; +/* ISO 7816 variables */ +/*! ISO 7816-3 state */ +enum iso7816_3_sniff_state iso_state = ISO7816_S_RESET; +/*! ATR state */ +enum atr_sniff_state atr_state; +/*! ATR data + * @remark can be used to check later protocol changes + */ +uint8_t atr[MAX_ATR_SIZE]; +/*! Current index in the ATR data */ +uint8_t atr_i = 0; +/*! If convention conversion is needed */ +bool convention_convert = false; +/*! The supported T protocols */ +uint16_t t_protocol_support = 0; +/*! PPS state + * @remark it is shared between request and response since they aren't simultaneous but follow the same procedure + */ +enum pps_sniff_state pps_state; +/*! PPS request data + * @remark can be used to check PPS response + */ +uint8_t pps_req[MAX_PPS_SIZE]; +/*! PPS response data */ +uint8_t pps_rsp[MAX_PPS_SIZE]; + /*------------------------------------------------------------------------------ * Internal functions *------------------------------------------------------------------------------*/ +/*! Convert data between direct and inverse convention + * @note direct convention is LSb first and HIGH=1; inverse conversion in MSb first and LOW=1 + * @remark use a look up table to speed up conversion + */ +static const uint8_t convention_convert_lut[256] = { 0xff, 0x7f, 0xbf, 0x3f, 0xdf, 0x5f, 0x9f, 0x1f, 0xef, 0x6f, 0xaf, 0x2f, 0xcf, 0x4f, 0x8f, 0x0f, 0xf7, 0x77, 0xb7, 0x37, 0xd7, 0x57, 0x97, 0x17, 0xe7, 0x67, 0xa7, 0x27, 0xc7, 0x47, 0x87, 0x07, 0xfb, 0x7b, 0xbb, 0x3b, 0xdb, 0x5b, 0x9b, 0x1b, 0xeb, 0x6b, 0xab, 0x2b, 0xcb, 0x4b, 0x8b, 0x0b, 0xf3, 0x73, 0xb3, 0x33, 0xd3, 0x53, 0x93, 0x13, 0xe3, 0x63, 0xa3, 0x23, 0xc3, 0x43, 0x83, 0x03, 0xfd, 0x7d, 0xbd, 0x3d, 0xdd, 0x5d, 0x9d, 0x1d, 0xed, 0x6d, 0xad, 0x2d, 0xcd, 0x4d, 0x8d, 0x0d, 0xf5, 0x75, 0xb5, 0x35, 0xd5, 0x55, 0x95, 0x15, 0xe5, 0x65, 0xa5, 0x25, 0xc5, 0x45, 0x85, 0x05, 0xf9, 0x79, 0xb9, 0x39, 0xd9, 0x59, 0x99, 0x19, 0xe9, 0x69, 0xa9, 0x29, 0xc9, 0x49, 0x89, 0x09, 0xf1, 0x71, 0xb1, 0x31, 0xd1, 0x51, 0x91, 0x11, 0xe1, 0x61, 0xa1, 0x21, 0xc1, 0x41, 0x81, 0x01, 0xfe, 0x7e, 0xbe, 0x3e, 0xde, 0x5e, 0x9e, 0x1e, 0xee, 0x6e, 0xae, 0x2e, 0xce, 0x4e, 0x8e, 0x0e, 0xf6, 0x76, 0xb6, 0x36, 0xd6, 0x56, 0x96, 0x16, 0xe6, 0x66, 0xa6, 0x26, 0xc6, 0x46, 0x86, 0x06, 0xfa, 0x7a, 0xba, 0x3a, 0xda, 0x5a, 0x9a, 0x1a, 0xea, 0x6a, 0xaa, 0x2a, 0xca, 0x4a, 0x8a, 0x0a, 0xf2, 0x72, 0xb2, 0x32, 0xd2, 0x52, 0x92, 0x12, 0xe2, 0x62, 0xa2, 0x22, 0xc2, 0x42, 0x82, 0x02, 0xfc, 0x7c, 0xbc, 0x3c, 0xdc, 0x5c, 0x9c, 0x1c, 0xec, 0x6c, 0xac, 0x2c, 0xcc, 0x4c, 0x8c, 0x0c, 0xf4, 0x74, 0xb4, 0x34, 0xd4, 0x54, 0x94, 0x14, 0xe4, 0x64, 0xa4, 0x24, 0xc4, 0x44, 0x84, 0x04, 0xf8, 0x78, 0xb8, 0x38, 0xd8, 0x58, 0x98, 0x18, 0xe8, 0x68, 0xa8, 0x28, 0xc8, 0x48, 0x88, 0x08, 0xf0, 0x70, 0xb0, 0x30, 0xd0, 0x50, 0x90, 0x10, 0xe0, 0x60, 0xa0, 0x20, 0xc0, 0x40, 0x80, 0x00, }; + +/*! Update the ISO 7816-3 state + * @param[in] iso_state_new new ISO 7816-3 state to update to + */ +static void change_state(enum iso7816_3_sniff_state iso_state_new) +{ + /* sanity check */ + if (iso_state_new==iso_state) { + TRACE_WARNING("Already in ISO 7816 state %u\n\r", iso_state); + return; + } + + /* handle actions to perform when switching state */ + switch (iso_state_new) { + case ISO7816_S_RESET: + update_fidi(sniff_usart.base, 0x11); /* reset baud rate to default Di/Fi values */ + // TODO disable USART and TC + break; + case ISO7816_S_WAIT_ATR: + rbuf_reset(&sniff_buffer); /* reset buffer for new communication */ + // TODO enable USART and TC + break; + case ISO7816_S_IN_ATR: + atr_i = 0; + convention_convert = false; + t_protocol_support = 0; + atr_state = ATR_S_WAIT_TS; + break; + case ISO7816_S_IN_PPS_REQ: + case ISO7816_S_IN_PPS_RSP: + pps_state = PPS_S_WAIT_PPSS; + break; + default: + break; + } + + /* save new state */ + iso_state = iso_state_new; + TRACE_INFO("Changed to ISO 7816-3 state %u\n\r", iso_state); +} + +/*! Process ATR byte + * @param[in] byte ATR byte to process + */ +static void process_byte_atr(uint8_t byte) +{ + static uint8_t atr_hist_len = 0; /* store the number of expected historical bytes */ + static uint8_t y = 0; /* last mask of the upcoming TA, TB, TC, TD interface bytes */ + + /* sanity check */ + if (ISO7816_S_IN_ATR!=iso_state) { + TRACE_ERROR("Processing ATR data in wrong ISO 7816-3 state %u\n\r", iso_state); + return; + } + if (atr_i>=ARRAY_SIZE(atr)) { + TRACE_WARNING("ATR data overflow\n\r"); + return; + } + + /* save data for use by other functions */ + atr[atr_i++] = byte; + + /* handle ATR byte depending on current state */ + switch (atr_state) { + case ATR_S_WAIT_TS: /* see ISO/IEC 7816-3:2006 section 8.1 */ + switch (byte) { + case 0x23: /* direct convention used, but decoded using inverse convention (a parity error should also have occurred) */ + case 0x30: /* inverse convention used, but decoded using direct convention (a parity error should also have occurred) */ + convention_convert = !convention_convert; + case 0x3b: /* direct convention used and correctly decoded */ + case 0x3f: /* inverse convention used and correctly decoded */ + atr_state = ATR_S_WAIT_T0; /* wait for format byte */ + break; + default: + atr_i--; /* revert last byte */ + TRACE_WARNING("Invalid TS received\n\r"); + } + break; + case ATR_S_WAIT_T0: /* see ISO/IEC 7816-3:2006 section 8.2.2 */ + case ATR_S_WAIT_TD: /* see ISO/IEC 7816-3:2006 section 8.2.3 */ + if (ATR_S_WAIT_T0==atr_state) { + atr_hist_len = (byte&0x0f); /* save the number of historical bytes */ + } else if (ATR_S_WAIT_TD==atr_state) { + t_protocol_support |= (1<<(byte&0x0f)); /* remember supported protocol to know if TCK will be present */ + } + y = (byte&0xf0); /* remember upcoming interface bytes */ + if (y&0x10) { + atr_state = ATR_S_WAIT_TA; /* wait for interface byte TA */ + break; + } + case ATR_S_WAIT_TA: /* see ISO/IEC 7816-3:2006 section 8.2.3 */ + if (y&0x20) { + atr_state = ATR_S_WAIT_TB; /* wait for interface byte TB */ + break; + } + case ATR_S_WAIT_TB: /* see ISO/IEC 7816-3:2006 section 8.2.3 */ + if (y&0x40) { + atr_state = ATR_S_WAIT_TC; /* wait for interface byte TC */ + break; + } + case ATR_S_WAIT_TC: /* see ISO/IEC 7816-3:2006 section 8.2.3 */ + if (y&0x80) { + atr_state = ATR_S_WAIT_TD; /* wait for interface byte TD */ + break; + } else if (atr_hist_len) { + atr_state = ATR_S_WAIT_HIST; /* wait for historical bytes */ + break; + } + case ATR_S_WAIT_HIST: /* see ISO/IEC 7816-3:2006 section 8.2.4 */ + if (atr_hist_len) { + atr_hist_len--; + } + if (0==atr_hist_len) { + if (t_protocol_support>1) { + atr_state = ATR_S_WAIT_TCK; /* wait for check bytes */ + break; + } + } else { + break; + } + case ATR_S_WAIT_TCK: /* see ISO/IEC 7816-3:2006 section 8.2.5 */ + /* we could verify the checksum, but we are just here to sniff */ + change_state(ISO7816_S_WAIT_APDU); /* go to next state */ + break; + default: + TRACE_INFO("Unknown ATR state %u\n\r", atr_state); + } +} + +static void process_byte_pps(uint8_t byte) +{ + uint8_t *pps_cur; /* current PPS (request or response) */ + + /* sanity check */ + if (ISO7816_S_IN_PPS_REQ==iso_state) { + pps_cur = pps_req; + } else if (ISO7816_S_IN_PPS_RSP==iso_state) { + pps_cur = pps_rsp; + } else { + TRACE_ERROR("Processing PPS data in wrong ISO 7816-3 state %u\n\r", iso_state); + return; + } + + /* handle PPS byte depending on current state */ + switch (pps_state) { /* see ISO/IEC 7816-3:2006 section 9.2 */ + case PPS_S_WAIT_PPSS: /*!< initial byte */ + if (0xff) { + pps_cur[0] = byte; + pps_state = PPS_S_WAIT_PPS0; /* go to next state */ + } else { + TRACE_INFO("Invalid PPSS received\n\r"); + change_state(ISO7816_S_WAIT_APDU); /* go back to APDU state */ + } + break; + case PPS_S_WAIT_PPS0: /*!< format byte */ + pps_cur[1] = byte; + if (pps_cur[1]&0x10) { + pps_state = PPS_S_WAIT_PPS1; /* go to next state */ + break; + } + case PPS_S_WAIT_PPS1: /*!< first parameter byte */ + pps_cur[2] = byte; /* not always right but doesn't affect the process */ + if (pps_cur[1]&0x20) { + pps_state = PPS_S_WAIT_PPS2; /* go to next state */ + break; + } + case PPS_S_WAIT_PPS2: /*!< second parameter byte */ + pps_cur[3] = byte; /* not always right but doesn't affect the process */ + if (pps_cur[1]&0x40) { + pps_state = PPS_S_WAIT_PPS3; /* go to next state */ + break; + } + case PPS_S_WAIT_PPS3: /*!< third parameter byte */ + pps_cur[4] = byte; /* not always right but doesn't affect the process */ + pps_state = PPS_S_WAIT_PCK; /* go to next state */ + break; + case PPS_S_WAIT_PCK: /*!< check byte */ + pps_cur[5] = byte; /* not always right but doesn't affect the process */ + /* verify the checksum */ + uint8_t check = 0; + check ^= pps_cur[0]; + check ^= pps_cur[1]; + if (pps_cur[1]&0x10) { + check ^= pps_cur[2]; + } + if (pps_cur[1]&0x20) { + check ^= pps_cur[3]; + } + if (pps_cur[1]&0x40) { + check ^= pps_cur[4]; + } + check ^= pps_cur[5]; + if (ISO7816_S_IN_PPS_REQ==iso_state) { + if (0==check) { /* checksum is valid */ + change_state(ISO7816_S_WAIT_PPS_RSP); /* go to next state */ + } else { /* checksum is invalid */ + change_state(ISO7816_S_WAIT_APDU); /* go to next state */ + } + } else if (ISO7816_S_IN_PPS_RSP==iso_state) { + if (0==check) { /* checksum is valid */ + uint8_t fn, dn; + if (pps_cur[1]&0x10) { + fn = (pps_cur[2]>>4); + dn = (pps_cur[2]&0x0f); + } else { + fn = 1; + dn = 1; + } + TRACE_INFO("PPS negotiation successful: Fn=%u Dn=%u\n\r", fn, dn); + update_fidi(sniff_usart.base, pps_cur[2]); + rbuf_reset(&sniff_buffer); /* reset buffer for new communication */ + } else { /* checksum is invalid */ + TRACE_INFO("PPS negotiation failed\n\r"); + } + change_state(ISO7816_S_WAIT_APDU); /* co to next state */ + } + break; + default: + TRACE_INFO("Unknown PPS state %u\n\r", pps_state); + } +} + +static void process_byte_apdu(uint8_t byte) +{ +} + static void check_sniffed_data(void) { - /* Display sniffed data */ + /* Handle sniffed data */ while (!rbuf_is_empty(&sniff_buffer)) { uint8_t byte = rbuf_read(&sniff_buffer); - TRACE_INFO_WP("0x%02x ", byte); + TRACE_WARNING_WP("< 0x%02x\n\r", byte); + switch (iso_state) { /* Handle byte depending on state */ + case ISO7816_S_RESET: /* During reset we shouldn't receive any data */ + break; + case ISO7816_S_WAIT_ATR: /* After a reset we expect the ATR */ + change_state(ISO7816_S_IN_ATR); /* go to next state */ + case ISO7816_S_IN_ATR: /* More ATR data incoming */ + process_byte_atr(byte); + break; + case ISO7816_S_WAIT_APDU: /* After the ATR we expect APDU or PPS data */ + case ISO7816_S_WAIT_PPS_RSP: + if (byte == 0xff) { + if (ISO7816_S_WAIT_PPS_RSP==iso_state) { + change_state(ISO7816_S_IN_PPS_RSP); /* Go to PPS state */ + } else { + change_state(ISO7816_S_IN_PPS_REQ); /* Go to PPS state */ + } + process_byte_pps(byte); + break; + } + case ISO7816_S_IN_APDU: /* More APDU data incoming */ + process_byte_apdu(byte); + break; + case ISO7816_S_IN_PPS_REQ: + case ISO7816_S_IN_PPS_RSP: + process_byte_pps(byte); + break; + default: + TRACE_ERROR("Data received in unknown state %u\n\r", iso_state); + } } } /*! Interrupt Service Routine called on USART activity */ -void Sniffer_usart_irq(void) +void Sniffer_usart_isr(void) { /* Read channel status register */ uint32_t csr = sniff_usart.base->US_CSR & sniff_usart.base->US_IMR; @@ -114,11 +424,36 @@ if (csr & US_CSR_RXRDY) { /* Read communication data byte between phone and SIM */ uint8_t byte = sniff_usart.base->US_RHR; + /* Convert convention if required */ + if (convention_convert) { + byte = convention_convert_lut[byte]; + } /* Store sniffed data into buffer (also clear interrupt */ rbuf_write(&sniff_buffer, byte); } } +/** PIO interrupt service routine to checks if the card reset line has changed + */ +static void Sniffer_reset_isr(const Pin* pPin) +{ + /* Ensure an edge on the reset pin cause the interrupt */ + if (pPin->id!=pin_rst.id || 0==(pPin->mask&pin_rst.mask)) { + TRACE_ERROR("Pin other than reset caused a interrupt\n\r"); + return; + } + /* Update the ISO state according to the reset change */ + if (PIO_Get(&pin_rst)) { + if (ISO7816_S_WAIT_ATR!=iso_state) { + change_state(ISO7816_S_WAIT_ATR); + } + } else { + if (ISO7816_S_RESET!=iso_state) { + change_state(ISO7816_S_RESET); + } + } +} + /*------------------------------------------------------------------------------ * Global functions *------------------------------------------------------------------------------*/ @@ -126,14 +461,14 @@ void Sniffer_usart1_irq(void) { if (ID_USART1==sniff_usart.id) { - Sniffer_usart_irq(); + Sniffer_usart_isr(); } } void Sniffer_usart0_irq(void) { if (ID_USART0==sniff_usart.id) { - Sniffer_usart_irq(); + Sniffer_usart_isr(); } } @@ -153,8 +488,9 @@ TRACE_INFO("Sniffer exit\n\r"); USART_DisableIt(sniff_usart.base, US_IER_RXRDY); /* NOTE: don't forget to set the IRQ according to the USART peripheral used */ - NVIC_DisableIRQ(USART0_IRQn); + NVIC_DisableIRQ(IRQ_USART_SIM); USART_SetReceiverEnabled(sniff_usart.base, 0); + } /* called when *Sniffer* configuration is set by host */ @@ -168,6 +504,12 @@ PIO_Configure(pins_bus, PIO_LISTSIZE(pins_bus)); /* Configure pins to forward phone power to card */ PIO_Configure(pins_power, PIO_LISTSIZE(pins_power)); + /* Enable interrupts on port with reset line */ + NVIC_EnableIRQ(PIOA_IRQn); /* CAUTION this needs to match to the correct port */ + /* Register ISR to handle card reset change */ + PIO_ConfigureIt(&pin_rst, &Sniffer_reset_isr); + /* Enable interrupt on card reset pin */ + PIO_EnableIt(&pin_rst); /* Clear ring buffer containing the sniffed data */ rbuf_reset(&sniff_buffer); @@ -180,10 +522,13 @@ /* Enable interrupt requests for the USART peripheral */ NVIC_EnableIRQ(IRQ_USART_SIM); - /* TODO configure RST pin ISR */ + /* Reset state */ + if (ISO7816_S_RESET!=iso_state) { + change_state(ISO7816_S_RESET); + } } -/* main (idle/busy) loop of this USB configuration */ +/* Main (idle/busy) loop of this USB configuration */ void Sniffer_run(void) { check_sniffed_data(); -- To view, visit https://gerrit.osmocom.org/9855 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: simtrace2 Gerrit-Branch: master Gerrit-MessageType: newchange Gerrit-Change-Id: I4b38ce1d80e370fda6aa181e959ba3f1286bb922 Gerrit-Change-Number: 9855 Gerrit-PatchSet: 1 Gerrit-Owner: Kévin Redon <kre...@sysmocom.de>
