rizin/subprojects/rzwinkd/kd.c
2022-06-05 00:27:35 +08:00

160 lines
3.6 KiB
C

// SPDX-FileCopyrightText: 2014-2017 LemonBoy <thatlemon@gmail.com>
// SPDX-License-Identifier: LGPL-3.0-only
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "kd.h"
#include <rz_util/rz_log.h>
#define KD_DBG if (false)
ut32 kd_data_checksum(const ut8 *buf, const ut64 buf_len) {
ut32 i, acc;
if (!buf || !buf_len) {
return 0;
}
for (i = acc = 0; i < buf_len; i++) {
acc += buf[i];
}
return acc;
}
int kd_send_ctrl_packet(io_desc_t *desc, const ut32 type, const ut32 id) {
kd_packet_t pkt;
pkt.leader = KD_PACKET_CTRL;
pkt.length = 0;
pkt.checksum = 0;
pkt.id = id;
pkt.type = type;
if (iob_write(desc, (ut8 *)&pkt, sizeof(kd_packet_t)) < 0) {
return KD_E_IOERR;
}
return KD_E_OK;
}
int kd_send_data_packet(io_desc_t *desc, const ut32 type, const ut32 id, const ut8 *req,
const int req_len, const ut8 *buf, const ut32 buf_len) {
kd_packet_t pkt;
if (req_len + buf_len > KD_MAX_PAYLOAD) {
return KD_E_MALFORMED;
}
RZ_LOG_DEBUG("==== Send Data ====\n");
RZ_LOG_DEBUG("ID: 0x%" PFMT32x "\n", id);
RZ_LOG_DEBUG("Type: 0x%" PFMT32x "\n", type);
pkt.leader = KD_PACKET_DATA;
pkt.length = req_len + buf_len;
pkt.checksum = kd_data_checksum(req, req_len) + kd_data_checksum(buf, buf_len);
pkt.id = id;
pkt.type = type;
if (iob_write(desc, (ut8 *)&pkt, sizeof(kd_packet_t)) < 0) {
return KD_E_IOERR;
}
if (iob_write(desc, (ut8 *)req, req_len) < 0) {
return KD_E_IOERR;
}
if (buf && iob_write(desc, (ut8 *)buf, buf_len) < 0) {
return KD_E_IOERR;
}
if (desc->iob->type == KD_IO_PIPE) {
if (iob_write(desc, (ut8 *)"\xAA", 1) < 0) {
return KD_E_IOERR;
}
}
return KD_E_OK;
}
int kd_read_packet(io_desc_t *desc, kd_packet_t **p) {
kd_packet_t pkt;
ut8 *buf;
*p = NULL;
if (iob_read(desc, (ut8 *)&pkt, sizeof(kd_packet_t)) <= 0) {
return KD_E_IOERR;
}
if (!kd_packet_is_valid(&pkt)) {
KD_DBG eprintf("invalid leader %08x, trying to recover\n", pkt.leader);
while (!kd_packet_is_valid(&pkt)) {
kd_send_ctrl_packet(desc, KD_PACKET_TYPE_RESEND, 0);
char sig[4];
// Read byte-by-byte searching for the start of a packet
int ret;
while ((ret = iob_read(desc, (ut8 *)&sig, 1)) > 0) {
if (sig[0] == '0' || sig[0] == 'i') {
if (iob_read(desc, (ut8 *)&sig + 1, 3) == 3) {
if (strncmp(sig, "000", 3) && strncmp(sig, "iii", 3)) {
continue;
}
memcpy(&pkt, sig, sizeof(sig));
if (iob_read(desc, (ut8 *)&pkt + 4, sizeof(kd_packet_t) - 4) <= 0) {
return KD_E_IOERR;
}
break;
} else {
return KD_E_IOERR;
}
}
}
if (!ret) {
return KD_E_IOERR;
}
}
}
buf = malloc(sizeof(kd_packet_t) + pkt.length);
if (!buf) {
return KD_E_IOERR;
}
memcpy(buf, &pkt, sizeof(kd_packet_t));
if (pkt.length) {
iob_read(desc, (ut8 *)buf + sizeof(kd_packet_t), pkt.length);
}
if (pkt.checksum != kd_data_checksum(buf + sizeof(kd_packet_t), pkt.length)) {
KD_DBG eprintf("Checksum mismatch!\n");
free(buf);
return KD_E_MALFORMED;
}
if (pkt.leader == KD_PACKET_DATA) {
if (desc->iob->type == KD_IO_PIPE) {
ut8 trailer;
iob_read(desc, (ut8 *)&trailer, 1);
if (trailer != 0xAA) {
KD_DBG eprintf("Missing trailer 0xAA\n");
free(buf);
return KD_E_MALFORMED;
}
}
}
kd_send_ctrl_packet(desc, KD_PACKET_TYPE_ACKNOWLEDGE, pkt.id);
*p = (kd_packet_t *)buf;
return KD_E_OK;
}
bool kd_packet_is_valid(const kd_packet_t *p) {
return p->leader == KD_PACKET_CTRL || p->leader == KD_PACKET_DATA || p->leader == KD_PACKET_UNUSED;
}
int kd_packet_is_ack(const kd_packet_t *p) {
return p->leader == KD_PACKET_CTRL && p->type == KD_PACKET_TYPE_ACKNOWLEDGE;
}