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restructure client

This commit is contained in:
xenia 2020-09-25 02:17:04 -04:00
parent 4a152aca63
commit d90e8873d9
1 changed files with 39 additions and 14 deletions
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53
stream-ciphers/client.c
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@ -1,10 +1,42 @@
#include <stdio.h>
#include <string.h>
#include <sys/random.h>
#include "epic_drm.h"
#define log(what) printf("[epic_drm] " what "\n")
#define logf(what, ...) printf("[epic_drm] " what "\n", __VA_ARGS__)
#define log(what) printf("[client] " what "\n")
#define logf(what, ...) printf("[client] " what "\n", __VA_ARGS__)
// this code is untrusted
// but don't worry, Epic DRM(tm) protections are unbreakable
void* get_cmd(struct command_channel* chan) {
// get the protected shell command from the DRM server
void* dst = malloc(sizeof(chan->data));
log("sending get_cmd");
chan->command = GET_CMD;
sem_post(&chan->sem_c2s);
sem_wait(&chan->sem_s2c);
logf("result: %s", chan->command == SUCCESS ? "success" : "error");
if (chan->command == SUCCESS) {
memcpy(dst, &chan->data, sizeof(chan->data));
return dst;
} else {
return NULL;
}
}
void send_cmd(struct command_channel* chan, void* data) {
// send a protected shell command back to the server
log("sending execute_cmd");
memcpy(&chan->data, data, sizeof(chan->data));
chan->command = EXECUTE_CMD;
sem_post(&chan->sem_c2s);
sem_wait(&chan->sem_s2c);
logf("result: %s", chan->command == SUCCESS ? "success" : "error");
}
int main() {
// perform a basic interaction with epic_drm
@ -12,15 +44,11 @@ int main() {
int shm = shm_open(SHM_NAME, O_RDWR, 0);
struct command_channel* chan = mmap(NULL, SHM_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, shm, 0);
log("sending get_cmd");
chan->command = GET_CMD;
sem_post(&chan->sem_c2s);
sem_wait(&chan->sem_s2c);
logf("result: %s", chan->command == SUCCESS ? "success" : "error");
// get protected shell command
void* data = get_cmd(chan);
log("data");
for (size_t i = 0; i < 64; i++) {
uint8_t b = ((uint8_t*) &chan->data)[i];
uint8_t b = ((uint8_t*)data)[i];
printf("%02x ", b);
if (i % 16 == 15) {
printf("\n");
@ -28,11 +56,8 @@ int main() {
}
printf("...\n");
log("sending execute_cmd");
chan->command = EXECUTE_CMD;
sem_post(&chan->sem_c2s);
sem_wait(&chan->sem_s2c);
logf("result: %s", chan->command == SUCCESS ? "success" : "error");
// send back
send_cmd(chan, data);
log("done");
}