Re: [libvirt] [PATCH v2 2/4] util: Introduce virGenerateRandomBytes

Using the existing virUUIDGenerateRandomBytes, move API to virutil.c and add it to libvirt_private.syms. This will be used as a fallback for generating a domain master key. Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/libvirt_private.syms | 1 + src/util/virutil.c | 36 ++++++++++++++++++++++++++++++++++++ src/util/virutil.h | 3 +++ src/util/viruuid.c | 30 +----------------------------- 4 files changed, 41 insertions(+), 29 deletions(-) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 7c44047..3d54c39 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2422,6 +2422,7 @@ virEnumToString; virFindFCHostCapableVport; virFindSCSIHostByPCI; virFormatIntDecimal; +virGenerateRandomBytes; virGetDeviceID; virGetDeviceUnprivSGIO; virGetEnvAllowSUID; diff --git a/src/util/virutil.c b/src/util/virutil.c index b401f8d..c55f6f6 100644 --- a/src/util/virutil.c +++ b/src/util/virutil.c @@ -2669,3 +2669,39 @@ virMemoryMaxValue(bool capped) else return LLONG_MAX; } + + +/** + * virGenerateRandomBytes + * @buf: Pointer to location to store bytes + * @buflen: Number of bytes to store + * + * Generate a stream of random bytes into @buf of size @buflen + */ +int +virGenerateRandomBytes(unsigned char *buf, + size_t buflen) +{ + int fd; + + if ((fd = open("/dev/urandom", O_RDONLY)) < 0) + return errno; + + while (buflen > 0) { + ssize_t n; + + if ((n = read(fd, buf, buflen)) <= 0) { + if (errno == EINTR) + continue; + VIR_FORCE_CLOSE(fd); + return n < 0 ? errno : ENODATA; + } + + buf += n; + buflen -= n; + } + + VIR_FORCE_CLOSE(fd); + + return 0; +} diff --git a/src/util/virutil.h b/src/util/virutil.h index b121de0..a398b38 100644 --- a/src/util/virutil.h +++ b/src/util/virutil.h @@ -254,6 +254,9 @@ unsigned long long virMemoryLimitTruncate(unsigned long long value); bool virMemoryLimitIsSet(unsigned long long value); unsigned long long virMemoryMaxValue(bool ulong); +int virGenerateRandomBytes(unsigned char *buf, size_t buflen) + ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK; +