anotherim/anotherim-desktop
2
0
Fork 0
Code Issues Pull requests Actions Packages Projects Releases Wiki Activity

Rewrite OMEMO crypt buffer logic to fix #474

Browse source
This commit is contained in:
Marvin W 2019-01-16 23:02:23 +01:00
parent 16329411a8
commit 8e14ac6d71
No known key found for this signature in database
GPG key ID: 072E9235DB996F2A
1 changed files with 47 additions and 17 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

64
plugins/signal-protocol/src/signal_helper.c
View file

@ -228,9 +228,17 @@ int signal_vala_encrypt(signal_buffer **output,
if (gcry_cipher_open(&ctx, algo, mode, 0)) return SG_ERR_UNKNOWN; if (gcry_cipher_open(&ctx, algo, mode, 0)) return SG_ERR_UNKNOWN;
signal_buffer* padded = 0;
signal_buffer* out_buf = 0;
goto no_error; goto no_error;
error: error:
gcry_cipher_close(ctx); gcry_cipher_close(ctx);
if (padded != 0) {
signal_buffer_bzero_free(padded);
}
if (out_buf != 0) {
signal_buffer_free(out_buf);
}
return SG_ERR_UNKNOWN; return SG_ERR_UNKNOWN;
no_error: no_error:
@ -255,19 +263,30 @@ no_error:
} }
size_t padded_len = plaintext_len + pad_len; size_t padded_len = plaintext_len + pad_len;
uint8_t padded[padded_len]; padded = signal_buffer_alloc(padded_len);
memset(padded + plaintext_len, pad_len, pad_len); if (padded == 0) {
memcpy(padded, plaintext, plaintext_len); goto error;
uint8_t out_buf[padded_len + tag_len];
if (gcry_cipher_encrypt(ctx, out_buf, padded_len, padded, padded_len)) goto error;
if (tag_len > 0) {
if (gcry_cipher_gettag(ctx, out_buf + padded_len, tag_len)) goto error;
} }
*output = signal_buffer_create(out_buf, padded_len + tag_len); memset(signal_buffer_data(padded) + plaintext_len, pad_len, pad_len);
memcpy(signal_buffer_data(padded), plaintext, plaintext_len);
out_buf = signal_buffer_alloc(padded_len + tag_len);
if (out_buf == 0) {
goto error;
}
if (gcry_cipher_encrypt(ctx, signal_buffer_data(out_buf), padded_len, signal_buffer_data(padded), padded_len)) goto error;
if (tag_len > 0) {
if (gcry_cipher_gettag(ctx, signal_buffer_data(out_buf) + padded_len, tag_len)) goto error;
}
*output = out_buf;
out_buf = 0;
signal_buffer_bzero_free(padded);
padded = 0;
gcry_cipher_close(ctx); gcry_cipher_close(ctx);
return SG_SUCCESS; return SG_SUCCESS;
@ -280,6 +299,7 @@ int signal_vala_decrypt(signal_buffer **output,
const uint8_t *ciphertext, size_t ciphertext_len, const uint8_t *ciphertext, size_t ciphertext_len,
void *user_data) { void *user_data) {
int algo, mode; int algo, mode;
*output = 0;
if (aes_cipher(cipher, key_len, &algo, &mode)) return SG_ERR_UNKNOWN; if (aes_cipher(cipher, key_len, &algo, &mode)) return SG_ERR_UNKNOWN;
if (ciphertext_len == 0) return SG_ERR_UNKNOWN; if (ciphertext_len == 0) return SG_ERR_UNKNOWN;
@ -289,9 +309,13 @@ int signal_vala_decrypt(signal_buffer **output,
if (gcry_cipher_open(&ctx, algo, mode, 0)) return SG_ERR_UNKNOWN; if (gcry_cipher_open(&ctx, algo, mode, 0)) return SG_ERR_UNKNOWN;
signal_buffer* out_buf = 0;
goto no_error; goto no_error;
error: error:
gcry_cipher_close(ctx); gcry_cipher_close(ctx);
if (out_buf != 0) {
signal_buffer_bzero_free(output);
}
return SG_ERR_UNKNOWN; return SG_ERR_UNKNOWN;
no_error: no_error:
@ -312,24 +336,30 @@ no_error:
tag_len = 16; tag_len = 16;
break; break;
default: default:
return SG_ERR_UNKNOWN; goto error;
} }
size_t padded_len = ciphertext_len - tag_len; size_t padded_len = ciphertext_len - tag_len;
uint8_t out_buf[padded_len]; out_buf = signal_buffer_alloc(padded_len);
if (out_buf == 0) {
goto error;
}
if (gcry_cipher_decrypt(ctx, out_buf, padded_len, ciphertext, padded_len)) goto error; if (gcry_cipher_decrypt(ctx, signal_buffer_data(out_buf), signal_buffer_len(out_buf), ciphertext, padded_len)) goto error;
if (tag_len > 0) { if (tag_len > 0) {
if (gcry_cipher_checktag(ctx, ciphertext + padded_len, tag_len)) goto error; if (gcry_cipher_checktag(ctx, ciphertext + padded_len, tag_len)) goto error;
} }
if (pkcs_pad) { if (pkcs_pad) {
uint8_t pad_len = out_buf[padded_len - 1]; uint8_t pad_len = signal_buffer_data(out_buf)[padded_len - 1];
if (pad_len > 16 || pad_len > padded_len) goto error; if (pad_len > 16 || pad_len > padded_len) goto error;
*output = signal_buffer_create(out_buf, padded_len - pad_len); *output = signal_buffer_create(signal_buffer_data(out_buf), padded_len - pad_len);
signal_buffer_bzero_free(out_buf);
out_buf = 0;
} else { } else {
*output = signal_buffer_create(out_buf, padded_len); *output = out_buf;
out_buf = 0;
} }
gcry_cipher_close(ctx); gcry_cipher_close(ctx);