wg: fix removing preshared keys

Also clean up related logic quite a bit and add unit tests.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This commit is contained in:
Jason A. Donenfeld 2017-11-23 01:17:25 +01:00
parent bc1f6be5db
commit 30cf5eb883

View File

@ -105,11 +105,59 @@ static inline bool parse_key(uint8_t key[static WG_KEY_LEN], const char *value)
{
if (!key_from_base64(key, value)) {
fprintf(stderr, "Key is not the correct length or format: `%s'\n", value);
memset(key, 0, WG_KEY_LEN);
return false;
}
return true;
}
static bool parse_keyfile(uint8_t key[static WG_KEY_LEN], const char *path)
{
FILE *f;
int c;
char dst[WG_KEY_LEN_BASE64];
bool ret = false;
f = fopen(path, "r");
if (!f) {
perror("fopen");
return false;
}
if (fread(dst, WG_KEY_LEN_BASE64 - 1, 1, f) != 1) {
if (errno) {
perror("fread");
goto out;
}
/* If we're at the end and we didn't read anything, we're /dev/null or an empty file. */
if (!ferror(f) && feof(f) && !ftell(f)) {
memset(key, 0, WG_KEY_LEN);
ret = true;
goto out;
}
fprintf(stderr, "Invalid length key in key file\n");
goto out;
}
dst[WG_KEY_LEN_BASE64 - 1] = '\0';
while ((c = getc(f)) != EOF) {
if (!isspace(c)) {
fprintf(stderr, "Found trailing character in key file: `%c'\n", c);
goto out;
}
}
if (ferror(f) && errno) {
perror("getc");
goto out;
}
ret = parse_key(key, dst);
out:
fclose(f);
return ret;
}
static inline bool parse_ip(struct wgallowedip *allowedip, const char *value)
{
allowedip->family = AF_UNSPEC;
@ -335,9 +383,7 @@ static bool process_line(struct config_ctx *ctx, const char *line)
ret = parse_fwmark(&ctx->device->fwmark, &ctx->device->flags, value);
else if (key_match("PrivateKey")) {
ret = parse_key(ctx->device->private_key, value);
if (!ret)
memset(ctx->device->private_key, 0, WG_KEY_LEN);
else
if (ret)
ctx->device->flags |= WGDEVICE_HAS_PRIVATE_KEY;
} else
goto error;
@ -354,9 +400,7 @@ static bool process_line(struct config_ctx *ctx, const char *line)
ret = parse_persistent_keepalive(&ctx->last_peer->persistent_keepalive_interval, &ctx->last_peer->flags, value);
else if (key_match("PresharedKey")) {
ret = parse_key(ctx->last_peer->preshared_key, value);
if (!ret)
memset(ctx->last_peer->preshared_key, 0, WG_KEY_LEN);
else if (!key_is_zero(ctx->last_peer->preshared_key))
if (ret)
ctx->last_peer->flags |= WGPEER_HAS_PRESHARED_KEY;
} else
goto error;
@ -429,54 +473,6 @@ err:
return NULL;
}
static bool read_keyfile(char dst[WG_KEY_LEN_BASE64], const char *path)
{
FILE *f;
int c;
bool ret = false;
f = fopen(path, "r");
if (!f) {
perror("fopen");
return false;
}
if (fread(dst, WG_KEY_LEN_BASE64 - 1, 1, f) != 1) {
if (errno) {
perror("fread");
goto out;
}
/* If we're at the end and we didn't read anything, we're /dev/null. */
if (!ferror(f) && feof(f) && !ftell(f)) {
static const uint8_t zeros[WG_KEY_LEN] = { 0 };
key_to_base64(dst, zeros);
ret = true;
goto out;
}
fprintf(stderr, "Invalid length key in key file\n");
goto out;
}
dst[WG_KEY_LEN_BASE64 - 1] = '\0';
while ((c = getc(f)) != EOF) {
if (!isspace(c)) {
fprintf(stderr, "Found trailing character in key file: `%c'\n", c);
goto out;
}
}
if (ferror(f) && errno) {
perror("getc");
goto out;
}
ret = true;
out:
fclose(f);
return ret;
}
static char *strip_spaces(const char *in)
{
char *out;
@ -517,14 +513,9 @@ struct wgdevice *config_read_cmd(char *argv[], int argc)
argv += 2;
argc -= 2;
} else if (!strcmp(argv[0], "private-key") && argc >= 2 && !peer) {
char key_line[WG_KEY_LEN_BASE64];
if (read_keyfile(key_line, argv[1])) {
if (!parse_key(device->private_key, key_line))
goto error;
device->flags |= WGDEVICE_HAS_PRIVATE_KEY;
} else
if (!parse_keyfile(device->private_key, argv[1]))
goto error;
device->flags |= WGDEVICE_HAS_PRIVATE_KEY;
argv += 2;
argc -= 2;
} else if (!strcmp(argv[0], "peer") && argc >= 2) {
@ -542,6 +533,7 @@ struct wgdevice *config_read_cmd(char *argv[], int argc)
peer = new_peer;
if (!parse_key(peer->public_key, argv[1]))
goto error;
peer->flags |= WGPEER_HAS_PUBLIC_KEY;
argv += 2;
argc -= 2;
} else if (!strcmp(argv[0], "remove") && argc >= 1 && peer) {
@ -571,15 +563,9 @@ struct wgdevice *config_read_cmd(char *argv[], int argc)
argv += 2;
argc -= 2;
} else if (!strcmp(argv[0], "preshared-key") && argc >= 2 && peer) {
char key_line[WG_KEY_LEN_BASE64];
if (read_keyfile(key_line, argv[1])) {
if (!parse_key(peer->preshared_key, key_line))
goto error;
if (!key_is_zero(peer->preshared_key))
peer->flags |= WGPEER_HAS_PRESHARED_KEY;
} else
if (!parse_keyfile(peer->preshared_key, argv[1]))
goto error;
peer->flags |= WGPEER_HAS_PRESHARED_KEY;
argv += 2;
argc -= 2;
} else {