asm_ppc_cs.c

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// SPDX-FileCopyrightText: 2014-2018 pancake <pancake@nopcode.org>
// SPDX-License-Identifier: LGPL-3.0-only
 
#include <rz_asm.h>
#include <rz_lib.h>
#include <capstone/capstone.h>
#include "../arch/ppc/libvle/vle.h"
#include "../arch/ppc/libps/libps.h"
 
static csh handle = 0;
 
static bool the_end(void *p) {
    if (handle) {
        cs_close(&handle);
        handle = 0;
    }
    return true;
}
 
static int decompile_vle(RzAsm *a, RzAsmOp *op, const ut8 *buf, int len) {
    vle_t *instr = 0;
    vle_handle handle = { 0 };
    if (len < 2) {
        return -1;
    }
    if (!vle_init(&handle, buf, len) && (instr = vle_next(&handle))) {
        op->size = instr->size;
        char buf_asm[64];
        vle_snprint(buf_asm, sizeof(buf_asm), a->pc, instr);
        rz_asm_op_set_asm(op, buf_asm);
        vle_free(instr);
    } else {
        rz_asm_op_set_asm(op, "invalid");
        op->size = 2;
        return -1;
    }
    return op->size;
}
 
static int decompile_ps(RzAsm *a, RzAsmOp *op, const ut8 *buf, int len) {
    ppcps_t instr = { 0 };
    if (len < 4) {
        return -1;
    }
    op->size = 4;
    const ut32 data = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
    if (libps_decode(data, &instr) < 1) {
        rz_asm_op_set_asm(op, "invalid");
        return -1;
    }
    char buf_asm[64];
    libps_snprint(buf_asm, sizeof(buf_asm), a->pc, &instr);
    rz_asm_op_set_asm(op, buf_asm);
    return op->size;
}
 
static int disassemble(RzAsm *a, RzAsmOp *op, const ut8 *buf, int len) {
    static int omode = -1, obits = -1;
    int n, ret, mode;
    ut64 off = a->pc;
    cs_insn *insn;
    if (a->cpu && strncmp(a->cpu, "vle", 3) == 0) {
        // vle is big-endian only
        if (!a->big_endian) {
            return -1;
        }
        ret = decompile_vle(a, op, buf, len);
        if (ret >= 0) {
            return op->size;
        }
    } else if (a->cpu && strncmp(a->cpu, "ps", 2) == 0) {
        // libps is big-endian only
        if (!a->big_endian) {
            return -1;
        }
        ret = decompile_ps(a, op, buf, len);
        if (ret >= 0) {
            return op->size;
        }
    }
    switch (a->bits) {
    case 32:
        mode = CS_MODE_32;
        break;
    case 64:
        mode = CS_MODE_64;
        break;
    default:
        mode = 0;
        break;
    }
    mode |= a->big_endian ? CS_MODE_BIG_ENDIAN : CS_MODE_LITTLE_ENDIAN;
    if (mode != omode || a->bits != obits) {
        cs_close(&handle);
        handle = 0;
        omode = mode;
        obits = a->bits;
    }
    if (handle == 0) {
        ret = cs_open(CS_ARCH_PPC, mode, &handle);
        if (ret != CS_ERR_OK) {
            return -1;
        }
    }
    op->size = 4;
    cs_option(handle, CS_OPT_DETAIL, CS_OPT_OFF);
    n = cs_disasm(handle, (const ut8 *)buf, len, off, 1, &insn);
    op->size = 4;
    if (n > 0 && insn->size > 0) {
        const char *opstr = sdb_fmt("%s%s%s", insn->mnemonic,
            insn->op_str[0] ? " " : "", insn->op_str);
        rz_asm_op_set_asm(op, opstr);
        cs_free(insn, n);
        return op->size;
    }
    rz_asm_op_set_asm(op, "invalid");
    op->size = 4;
    cs_free(insn, n);
    return op->size;
}
 
RzAsmPlugin rz_asm_plugin_ppc_cs = {
    .name = "ppc",
    .desc = "Capstone PowerPC disassembler",
    .license = "BSD",
    .author = "pancake",
    .arch = "ppc",
    .cpus = "ppc,vle,ps",
    .bits = 32 | 64,
    .endian = RZ_SYS_ENDIAN_LITTLE | RZ_SYS_ENDIAN_BIG,
    .fini = the_end,
    .disassemble = &disassemble,
};
 
#ifndef RZ_PLUGIN_INCORE
RZ_API RzLibStruct rizin_plugin = {
    .type = RZ_LIB_TYPE_ASM,
    .data = &rz_asm_plugin_ppc_cs,
    .version = RZ_VERSION
};
#endif