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author | Jason A. Donenfeld <Jason@zx2c4.com> | 2019-02-28 23:37:24 +0100 |
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committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2019-02-28 23:53:00 +0100 |
commit | 033dc8974de052c1f1ab5d735ec2ee921127e352 (patch) | |
tree | 1eb70e88bfa63b77ef7d682d723b5f8613d83525 /contrib/examples | |
parent | wg-quick: freebsd: rebreak interface loopback, while fixing localhost (diff) | |
download | wireguard-monolithic-historical-033dc8974de052c1f1ab5d735ec2ee921127e352.tar.xz wireguard-monolithic-historical-033dc8974de052c1f1ab5d735ec2ee921127e352.zip |
tools: genkey: account for short reads of /dev/urandom
Apparently Haiku has a misbehaving /dev/urandom.
While we're at it, simplify the function signature to completely succeed
or completely fail and make sure the caller checks the result.
Reported-by: Alexander von Gluck IV <kallisti5@unixzen.com>
Nitpicked-by: Aaron Jones <aaronmdjones@gmail.com>
Diffstat (limited to '')
-rw-r--r-- | contrib/examples/embeddable-wg-library/wireguard.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/contrib/examples/embeddable-wg-library/wireguard.c b/contrib/examples/embeddable-wg-library/wireguard.c index 51da8ec..54b8700 100644 --- a/contrib/examples/embeddable-wg-library/wireguard.c +++ b/contrib/examples/embeddable-wg-library/wireguard.c @@ -1751,16 +1751,21 @@ void wg_generate_private_key(wg_key private_key) void wg_generate_preshared_key(wg_key preshared_key) { ssize_t ret; + size_t i; int fd; - -#if defined(__NR_getrandom) - ret = syscall(__NR_getrandom, preshared_key, sizeof(wg_key), 0); - if (ret == sizeof(wg_key)) +#if defined(__OpenBSD__) || (defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_12) || (defined(__GLIBC__) && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 25))) + if (!getentropy(preshared_key, sizeof(wg_key))) + return; +#endif +#if defined(__NR_getrandom) && defined(__linux__) + if (syscall(__NR_getrandom, preshared_key, sizeof(wg_key), 0) == sizeof(wg_key)) return; #endif fd = open("/dev/urandom", O_RDONLY); assert(fd >= 0); - ret = read(fd, preshared_key, sizeof(wg_key)); + for (i = 0; i < sizeof(wg_key); i += ret) { + ret = read(fd, preshared_key + i, sizeof(wg_key) - i); + assert(ret > 0); + } close(fd); - assert(ret == sizeof(wg_key)); } |