Fam Zheng | cea2527 | 2016-09-21 12:27:14 +0800 | [diff] [blame] | 1 | /* |
| 2 | * QEMU UUID functions |
| 3 | * |
| 4 | * Copyright 2016 Red Hat, Inc. |
| 5 | * |
| 6 | * Authors: |
| 7 | * Fam Zheng <famz@redhat.com> |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify it |
| 10 | * under the terms of the GNU General Public License as published by the Free |
| 11 | * Software Foundation; either version 2 of the License, or (at your option) |
| 12 | * any later version. |
| 13 | * |
| 14 | */ |
| 15 | |
| 16 | #include "qemu/osdep.h" |
| 17 | #include "qemu-common.h" |
| 18 | #include "qemu/uuid.h" |
| 19 | #include "qemu/bswap.h" |
| 20 | |
| 21 | void qemu_uuid_generate(QemuUUID *uuid) |
| 22 | { |
| 23 | int i; |
| 24 | uint32_t tmp[4]; |
| 25 | |
| 26 | QEMU_BUILD_BUG_ON(sizeof(QemuUUID) != 16); |
| 27 | |
| 28 | for (i = 0; i < 4; ++i) { |
| 29 | tmp[i] = g_random_int(); |
| 30 | } |
| 31 | memcpy(uuid, tmp, sizeof(tmp)); |
| 32 | /* Set the two most significant bits (bits 6 and 7) of the |
| 33 | clock_seq_hi_and_reserved to zero and one, respectively. */ |
| 34 | uuid->data[8] = (uuid->data[8] & 0x3f) | 0x80; |
| 35 | /* Set the four most significant bits (bits 12 through 15) of the |
| 36 | time_hi_and_version field to the 4-bit version number. |
| 37 | */ |
| 38 | uuid->data[6] = (uuid->data[6] & 0xf) | 0x40; |
| 39 | } |
| 40 | |
| 41 | int qemu_uuid_is_null(const QemuUUID *uu) |
| 42 | { |
Fam Zheng | 3630be7 | 2016-09-21 12:27:15 +0800 | [diff] [blame] | 43 | static QemuUUID null_uuid; |
Fam Zheng | cea2527 | 2016-09-21 12:27:14 +0800 | [diff] [blame] | 44 | return memcmp(uu, &null_uuid, sizeof(QemuUUID)) == 0; |
| 45 | } |
| 46 | |
| 47 | void qemu_uuid_unparse(const QemuUUID *uuid, char *out) |
| 48 | { |
| 49 | const unsigned char *uu = &uuid->data[0]; |
| 50 | snprintf(out, UUID_FMT_LEN + 1, UUID_FMT, |
| 51 | uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], uu[7], |
| 52 | uu[8], uu[9], uu[10], uu[11], uu[12], uu[13], uu[14], uu[15]); |
| 53 | } |
| 54 | |
| 55 | char *qemu_uuid_unparse_strdup(const QemuUUID *uuid) |
| 56 | { |
| 57 | const unsigned char *uu = &uuid->data[0]; |
| 58 | return g_strdup_printf(UUID_FMT, |
| 59 | uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], |
| 60 | uu[7], uu[8], uu[9], uu[10], uu[11], uu[12], |
| 61 | uu[13], uu[14], uu[15]); |
| 62 | } |
| 63 | |
Fam Zheng | 0d6ae94 | 2016-09-21 12:27:23 +0800 | [diff] [blame] | 64 | static bool qemu_uuid_is_valid(const char *str) |
| 65 | { |
| 66 | int i; |
| 67 | |
| 68 | for (i = 0; i < strlen(str); i++) { |
| 69 | const char c = str[i]; |
| 70 | if (i == 8 || i == 13 || i == 18 || i == 23) { |
| 71 | if (str[i] != '-') { |
| 72 | return false; |
| 73 | } |
| 74 | } else { |
| 75 | if ((c >= '0' && c <= '9') || |
| 76 | (c >= 'A' && c <= 'F') || |
| 77 | (c >= 'a' && c <= 'f')) { |
| 78 | continue; |
| 79 | } |
| 80 | return false; |
| 81 | } |
| 82 | } |
| 83 | return i == 36; |
| 84 | } |
| 85 | |
Fam Zheng | 9c5ce8d | 2016-09-21 12:27:22 +0800 | [diff] [blame] | 86 | int qemu_uuid_parse(const char *str, QemuUUID *uuid) |
Fam Zheng | cea2527 | 2016-09-21 12:27:14 +0800 | [diff] [blame] | 87 | { |
Fam Zheng | 9c5ce8d | 2016-09-21 12:27:22 +0800 | [diff] [blame] | 88 | unsigned char *uu = &uuid->data[0]; |
Fam Zheng | cea2527 | 2016-09-21 12:27:14 +0800 | [diff] [blame] | 89 | int ret; |
| 90 | |
Fam Zheng | 0d6ae94 | 2016-09-21 12:27:23 +0800 | [diff] [blame] | 91 | if (!qemu_uuid_is_valid(str)) { |
Fam Zheng | cea2527 | 2016-09-21 12:27:14 +0800 | [diff] [blame] | 92 | return -1; |
| 93 | } |
| 94 | |
Fam Zheng | 9c5ce8d | 2016-09-21 12:27:22 +0800 | [diff] [blame] | 95 | ret = sscanf(str, UUID_FMT, &uu[0], &uu[1], &uu[2], &uu[3], |
| 96 | &uu[4], &uu[5], &uu[6], &uu[7], &uu[8], &uu[9], |
| 97 | &uu[10], &uu[11], &uu[12], &uu[13], &uu[14], |
| 98 | &uu[15]); |
Fam Zheng | cea2527 | 2016-09-21 12:27:14 +0800 | [diff] [blame] | 99 | |
| 100 | if (ret != 16) { |
| 101 | return -1; |
| 102 | } |
| 103 | return 0; |
| 104 | } |
| 105 | |
| 106 | /* Swap from UUID format endian (BE) to the opposite or vice versa. |
| 107 | */ |
| 108 | void qemu_uuid_bswap(QemuUUID *uuid) |
| 109 | { |
| 110 | assert(QEMU_PTR_IS_ALIGNED(uuid, sizeof(uint32_t))); |
| 111 | bswap32s(&uuid->fields.time_low); |
| 112 | bswap16s(&uuid->fields.time_mid); |
| 113 | bswap16s(&uuid->fields.time_high_and_version); |
| 114 | } |