regonly size sistemata in assembler, sistemati flag CF / ZF nei CMP e nei JMP

This commit is contained in:
Giulio De Pasquale 2017-05-25 15:25:45 +02:00
parent 19b6c69237
commit 6f9e7db4ee
3 changed files with 23 additions and 21 deletions

View File

@ -125,7 +125,7 @@ class VMAssembler:
for f in self.functions: for f in self.functions:
print("FUNCTION {}".format(f.name)) print("FUNCTION {}".format(f.name))
for idx, ins in enumerate(f.instructions): for idx, ins in enumerate(f.instructions):
print("{}:\t{}".format(hex(f.offset_of_instruction(idx)), ins)) print("{}:\t{}".format(hex(f.offset+ f.offset_of_instruction(idx)), ins))
def imm2reg(self, instruction): def imm2reg(self, instruction):
""" """
@ -475,7 +475,7 @@ ops_sizes = {"reg2reg": 2,
"imm2reg": 4, "imm2reg": 4,
"reg2imm": 4, "reg2imm": 4,
"byt2reg": 3, "byt2reg": 3,
"regonly": 3, "regonly": 2,
"immonly": 3, "immonly": 3,
"jump": 3, "jump": 3,
"single": 1} "single": 1}

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@ -4,16 +4,18 @@
#include <string.h> #include <string.h>
#include <unistd.h> #include <unistd.h>
void encrypt(uint16_t *v, uint16_t *k) { void encrypt(uint16_t *v) {
uint16_t v0 = v[0], v1 = v[1], sum = 0, i; /* set up */ uint16_t v0 = v[0], v1 = v[1], sum = 0, i; /* set up */
//uint32_t delta = 0x9e3779b9; /* a key schedule constant */ uint16_t delta= 0x626f;
uint16_t delta= 0x9e37; uint16_t k0 = 0x7065; // "pe"
uint16_t k0 = k[0], k1 = k[1], k2 = k[2], k3 = k[3]; /* cache key */ uint16_t k1 = 0x7065; // "pe"
for (i = 0; i < 64; i++) { /* basic cycle start */ uint16_t k2 = 0x7275; // "ru"
uint16_t k3 = 0x6e73; // "ns"
for (i = 0; i < 128; i++) {
sum += delta; sum += delta;
v0 += ((v1 << 4) + k0) ^ (v1 + sum) ^ ((v1 >> 5) + k1); v0 += ((v1 << 4) + k0) ^ (v1 + sum) ^ ((v1 >> 5) + k1);
v1 += ((v0 << 4) + k2) ^ (v0 + sum) ^ ((v0 >> 5) + k3); v1 += ((v0 << 4) + k2) ^ (v0 + sum) ^ ((v0 >> 5) + k3);
} /* end cycle */ }
v[0] = v0; v[0] = v0;
v[1] = v1; v[1] = v1;
} }
@ -22,14 +24,14 @@ int main(int argc, char *argv[]) {
uint8_t *buf; uint8_t *buf;
uint32_t buflen, i; uint32_t buflen, i;
if (argc != 3) { if (argc != 2) {
printf("Usage: %s text_to_encrypt key", argv[0]); printf("Usage: %s text_to_encrypt", argv[0]);
exit(1); exit(1);
} }
buflen = strlen(argv[1]); buflen = strlen(argv[1]);
buf = (uint8_t *)malloc(buflen); buf = (uint8_t *)malloc(buflen);
memcpy(buf, argv[1], buflen); memcpy(buf, argv[1], buflen);
encrypt((uint16_t *)buf, (uint16_t *)argv[2]); encrypt((uint16_t *)buf);
printf("Result:\n"); printf("Result:\n");
for (i = 0; i < buflen; i++) { for (i = 0; i < buflen; i++) {
printf("%02x", buf[i]); printf("%02x", buf[i]);

View File

@ -577,9 +577,9 @@ bool VM::execCMPB(void) {
flags.ZF = 0; flags.ZF = 0;
} }
if (*((uint8_t *)&regs[reg]) > imm) { if (*((uint8_t *)&regs[reg]) > imm) {
flags.CF = 1;
} else {
flags.CF = 0; flags.CF = 0;
} else {
flags.CF = 1;
} }
return true; return true;
} }
@ -599,9 +599,9 @@ bool VM::execCMPW(void) {
flags.ZF = 0; flags.ZF = 0;
} }
if (regs[reg] > imm) { if (regs[reg] > imm) {
flags.CF = 1;
} else {
flags.CF = 0; flags.CF = 0;
} else {
flags.CF = 1;
} }
return true; return true;
} }
@ -621,9 +621,9 @@ bool VM::execCMPR(void) {
flags.ZF = 0; flags.ZF = 0;
} }
if (regs[r1] > regs[r2]) { if (regs[r1] > regs[r2]) {
flags.CF = 1;
} else {
flags.CF = 0; flags.CF = 0;
} else {
flags.CF = 1;
} }
return true; return true;
} }
@ -657,7 +657,7 @@ bool VM::execJPAI(void) {
imm = *(uint16_t *)&as.code[regs[IP] + 1]; imm = *(uint16_t *)&as.code[regs[IP] + 1];
DBG_INFO(("JPAI 0x%x\n", imm)); DBG_INFO(("JPAI 0x%x\n", imm));
if (flags.CF == 1) { if (flags.CF == 0 && flags.ZF == 0) {
regs[IP] = imm; regs[IP] = imm;
return true; return true;
} }
@ -671,7 +671,7 @@ bool VM::execJPAR(void) {
reg = as.code[regs[IP] + 1]; reg = as.code[regs[IP] + 1];
DBG_INFO(("JPAR %s = 0x%x\n", getRegName(reg), regs[reg])); DBG_INFO(("JPAR %s = 0x%x\n", getRegName(reg), regs[reg]));
if (flags.CF == 1) { if (flags.CF == 0 && flags.ZF == 0) {
regs[IP] = reg; regs[IP] = reg;
return true; return true;
} }
@ -685,7 +685,7 @@ bool VM::execJPBI(void) {
imm = *(uint16_t *)&as.code[regs[IP] + 1]; imm = *(uint16_t *)&as.code[regs[IP] + 1];
DBG_INFO(("JPBI 0x%x\n", imm)); DBG_INFO(("JPBI 0x%x\n", imm));
if (flags.CF == 0) { if (flags.CF == 1) {
regs[IP] = imm; regs[IP] = imm;
return true; return true;
} }
@ -699,7 +699,7 @@ bool VM::execJPBR(void) {
reg = as.code[regs[IP] + 1]; reg = as.code[regs[IP] + 1];
DBG_INFO(("JPBR %s = 0x%x\n", getRegName(reg), regs[reg])); DBG_INFO(("JPBR %s = 0x%x\n", getRegName(reg), regs[reg]));
if (flags.CF == 0) { if (flags.CF == 1) {
regs[IP] = reg; regs[IP] = reg;
return true; return true;
} }