diff options
Diffstat (limited to 'sys-utils/lscpu-dmi.c')
-rw-r--r-- | sys-utils/lscpu-dmi.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/sys-utils/lscpu-dmi.c b/sys-utils/lscpu-dmi.c new file mode 100644 index 0000000..29bd2e4 --- /dev/null +++ b/sys-utils/lscpu-dmi.c @@ -0,0 +1,305 @@ +/* + * lscpu-dmi - Module to parse SMBIOS information + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Code originally taken from the dmidecode utility and slightly rewritten + * to suite the needs of lscpu + */ +#include <errno.h> +#include <stdlib.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <string.h> +#include <stdio.h> + +#include "lscpu.h" + +#define _PATH_SYS_DMI "/sys/firmware/dmi/tables/DMI" + +#define WORD(x) (uint16_t)(*(const uint16_t *)(x)) +#define DWORD(x) (uint32_t)(*(const uint32_t *)(x)) + +struct dmi_header +{ + uint8_t type; + uint8_t length; + uint16_t handle; + uint8_t *data; +}; + +static int checksum(const uint8_t *buf, size_t len) +{ + uint8_t sum = 0; + size_t a; + + for (a = 0; a < len; a++) + sum += buf[a]; + return (sum == 0); +} + +static void *get_mem_chunk(size_t base, size_t len, const char *devmem) +{ + void *p = NULL; + int fd; + + if ((fd = open(devmem, O_RDONLY)) < 0) + return NULL; + + if (!(p = malloc(len))) + goto nothing; + if (lseek(fd, base, SEEK_SET) == -1) + goto nothing; + if (read_all(fd, p, len) == -1) + goto nothing; + + close(fd); + return p; + +nothing: + free(p); + close(fd); + return NULL; +} + +static void to_dmi_header(struct dmi_header *h, uint8_t *data) +{ + h->type = data[0]; + h->length = data[1]; + h->handle = WORD(data + 2); + h->data = data; +} + +static char *dmi_string(const struct dmi_header *dm, uint8_t s) +{ + char *bp = (char *)dm->data; + + if (s == 0) + return NULL; + + bp += dm->length; + while (s > 1 && *bp) + { + bp += strlen(bp); + bp++; + s--; + } + + if (!*bp) + return NULL; + + return bp; +} + +static int hypervisor_from_dmi_table(uint32_t base, uint16_t len, + uint16_t num, const char *devmem) +{ + uint8_t *buf; + uint8_t *data; + int i = 0; + char *vendor = NULL; + char *product = NULL; + char *manufacturer = NULL; + int rc = HYPER_NONE; + + data = buf = get_mem_chunk(base, len, devmem); + if (!buf) + goto done; + + /* 4 is the length of an SMBIOS structure header */ + while (i < num && data + 4 <= buf + len) { + uint8_t *next; + struct dmi_header h; + + to_dmi_header(&h, data); + + /* + * If a short entry is found (less than 4 bytes), not only it + * is invalid, but we cannot reliably locate the next entry. + * Better stop at this point. + */ + if (h.length < 4) + goto done; + + /* look for the next handle */ + next = data + h.length; + while (next - buf + 1 < len && (next[0] != 0 || next[1] != 0)) + next++; + next += 2; + switch (h.type) { + case 0: + vendor = dmi_string(&h, data[0x04]); + break; + case 1: + manufacturer = dmi_string(&h, data[0x04]); + product = dmi_string(&h, data[0x05]); + break; + default: + break; + } + + data = next; + i++; + } + if (manufacturer && !strcmp(manufacturer, "innotek GmbH")) + rc = HYPER_INNOTEK; + else if (manufacturer && strstr(manufacturer, "HITACHI") && + product && strstr(product, "LPAR")) + rc = HYPER_HITACHI; + else if (vendor && !strcmp(vendor, "Parallels")) + rc = HYPER_PARALLELS; +done: + free(buf); + return rc; +} + +#if defined(__x86_64__) || defined(__i386__) +static int hypervisor_decode_legacy(uint8_t *buf, const char *devmem) +{ + if (!checksum(buf, 0x0F)) + return -1; + + return hypervisor_from_dmi_table(DWORD(buf + 0x08), WORD(buf + 0x06), + WORD(buf + 0x0C), + devmem); +} +#endif + +static int hypervisor_decode_smbios(uint8_t *buf, const char *devmem) +{ + if (!checksum(buf, buf[0x05]) + || memcmp(buf + 0x10, "_DMI_", 5) != 0 + || !checksum(buf + 0x10, 0x0F)) + return -1; + + return hypervisor_from_dmi_table(DWORD(buf + 0x18), WORD(buf + 0x16), + WORD(buf + 0x1C), + devmem); +} + +static int hypervisor_decode_sysfw(void) +{ + static char const sys_fw_dmi_tables[] = _PATH_SYS_DMI; + struct stat st; + + if (stat(sys_fw_dmi_tables, &st)) + return -1; + + return hypervisor_from_dmi_table(0, st.st_size, st.st_size / 4, + sys_fw_dmi_tables); +} + +/* + * Probe for EFI interface + */ +#define EFI_NOT_FOUND (-1) +#define EFI_NO_SMBIOS (-2) +static int address_from_efi(size_t *address) +{ + FILE *tab; + char linebuf[64]; + int ret; + + *address = 0; /* Prevent compiler warning */ + + /* + * Linux up to 2.6.6: /proc/efi/systab + * Linux 2.6.7 and up: /sys/firmware/efi/systab + */ + if (!(tab = fopen("/sys/firmware/efi/systab", "r")) && + !(tab = fopen("/proc/efi/systab", "r"))) + return EFI_NOT_FOUND; /* No EFI interface */ + + ret = EFI_NO_SMBIOS; + while ((fgets(linebuf, sizeof(linebuf) - 1, tab)) != NULL) { + char *addrp = strchr(linebuf, '='); + if (!addrp) + continue; + *(addrp++) = '\0'; + if (strcmp(linebuf, "SMBIOS") == 0) { + *address = strtoul(addrp, NULL, 0); + ret = 0; + break; + } + } + + fclose(tab); + return ret; +} + +int read_hypervisor_dmi(void) +{ + int rc = HYPER_NONE; + uint8_t *buf = NULL; + size_t fp = 0; + + if (sizeof(uint8_t) != 1 + || sizeof(uint16_t) != 2 + || sizeof(uint32_t) != 4 + || '\0' != 0) + goto done; + + /* -1 : no DMI in /sys, + * 0 : DMI exist, nothing detected (HYPER_NONE) + * >0 : hypervisor detected + */ + rc = hypervisor_decode_sysfw(); + if (rc >= HYPER_NONE) + goto done; + + /* First try EFI (ia64, Intel-based Mac) */ + switch (address_from_efi(&fp)) { + case EFI_NOT_FOUND: + goto memory_scan; + case EFI_NO_SMBIOS: + goto done; + } + + buf = get_mem_chunk(fp, 0x20, _PATH_DEV_MEM); + if (!buf) + goto done; + + rc = hypervisor_decode_smbios(buf, _PATH_DEV_MEM); + if (rc >= HYPER_NONE) + goto done; + + free(buf); + buf = NULL; +memory_scan: +#if defined(__x86_64__) || defined(__i386__) + /* Fallback to memory scan (x86, x86_64) */ + buf = get_mem_chunk(0xF0000, 0x10000, _PATH_DEV_MEM); + if (!buf) + goto done; + + for (fp = 0; fp <= 0xFFF0; fp += 16) { + if (memcmp(buf + fp, "_SM_", 4) == 0 && fp <= 0xFFE0) { + rc = hypervisor_decode_smbios(buf + fp, _PATH_DEV_MEM); + if (rc < 0) + fp += 16; + + } else if (memcmp(buf + fp, "_DMI_", 5) == 0) + rc = hypervisor_decode_legacy(buf + fp, _PATH_DEV_MEM); + + if (rc >= HYPER_NONE) + break; + } +#endif +done: + free(buf); + return rc < 0 ? HYPER_NONE : rc; +} |