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Solve challenge 7

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This commit is contained in:
Dimitri Lozeve 2020-06-05 18:45:59 +02:00
parent 02ca35a4ff
commit 8d9878964a
1 changed files with 20 additions and 8 deletions
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28
src/ex07/main.c
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@ -23,10 +23,14 @@ int main(int argc, char *argv[]) {
}
char input[BUF_SIZE] = {'\0'};
size_t nread = fread(input, 1, BUF_SIZE, fp);
if (nread == 0) {
printf("Cannot read any character from file %s\n", filename);
return EXIT_FAILURE;
int c;
size_t nread = 0;
while ((c = fgetc(fp)) != EOF) {
if (c == '\n' || c == '\r') { // ignore newlines
continue;
}
input[nread] = c;
nread++;
}
unsigned char buf[BUF_SIZE] = {0};
@ -46,12 +50,20 @@ int main(int argc, char *argv[]) {
}
unsigned char output[BUF_SIZE] = {0};
err = mbedtls_aes_crypt_ecb(&aes, MBEDTLS_AES_DECRYPT, buf, output);
if (err) {
printf("Could not decode buffer\n");
return EXIT_FAILURE;
// Decrypt block by block
for (size_t i = 0; i <= BUF_SIZE - 16; i += 16) {
if (buf[i] == 0) {
break;
}
err = mbedtls_aes_crypt_ecb(&aes, MBEDTLS_AES_DECRYPT, buf + i, output + i);
if (err) {
printf("Could not decode buffer\n");
return EXIT_FAILURE;
}
}
printf("%s", output);
if (fclose(fp)) {
printf("Error closing file %s\n", filename);
return EXIT_FAILURE;