Differential D57046 Diff 177989 sysutils/cpu-microcode-intel/files/ucode-split.c

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sysutils/cpu-microcode-intel/files/ucode-split.c

Show First 20 Lines • Show All 44 Lines • ▼ Show 20 Lines	struct microcode_update_header {
uint32_t checksum; /* Over update data and header */		uint32_t checksum; /* Over update data and header */
uint32_t loader_revision;		uint32_t loader_revision;
uint32_t processor_flags;		uint32_t processor_flags;
uint32_t data_size;		uint32_t data_size;
uint32_t total_size;		uint32_t total_size;
uint32_t reserved[3];		uint32_t reserved[3];
};		};

		/* SDM (March 2026) vol 3A 12.11.2 Optional Extended Signature Table. */
		struct ucode_intel_extsig_table {
		uint32_t signature_count;
		uint32_t checksum;
		uint32_t reserved[3];
		};

		struct ucode_intel_extsig {
		uint32_t processor_signature;
		uint32_t processor_flags;
		uint32_t checksum;
		};

/*		/*
* SDM vol 2A CPUID EAX = 01h Returns Model, Family, Stepping Information.		* SDM vol 2A CPUID EAX = 01h Returns Model, Family, Stepping Information.
* Caller must free the returned string.		* Caller must free the returned string.
*/		*/

static char *		static char *
format_signature(uint32_t signature)		format_signature(uint32_t signature)
{		{
▲ Show 20 Lines • Show All 41 Lines • ▼ Show 20 Lines	dump_header(const struct microcode_update_header *hdr)
printf("datasize\t0x%x\t\t0x%x\n", hdr->data_size,		printf("datasize\t0x%x\t\t0x%x\n", hdr->data_size,
hdr->data_size != 0 ? hdr->data_size : 2000);		hdr->data_size != 0 ? hdr->data_size : 2000);
printf("size\t\t0x%x\t\t0x%x\n", hdr->total_size,		printf("size\t\t0x%x\t\t0x%x\n", hdr->total_size,
hdr->total_size != 0 ? hdr->total_size : 2048);		hdr->total_size != 0 ? hdr->total_size : 2048);
free(sig_str);		free(sig_str);
}		}

static void		static void
		copy_entry(int ifd, off_t entry_start, uint32_t total_size,
		const char output_file, char buf, bool vflag)
		{
		off_t off;
		size_t len, resid;
		ssize_t rv;
		int ofd;

		ofd = open(output_file, O_WRONLY \| O_CREAT \| O_TRUNC, 0600);
		if (ofd < 0)
		err(1, "open");

		resid = total_size;
		off = entry_start;
		while (resid > 0) {
		len = resid < bufsize ? resid : bufsize;
		rv = pread(ifd, buf, len, off);
		if (rv < 0)
		err(1, "pread");
		else if (rv < (ssize_t)len)
		errx(1, "truncated microcode data");
		if (write(ofd, buf, len) < (ssize_t)len)
		err(1, "write");
		resid -= len;
		off += len;
		}
		if (vflag)
		printf("written to %s\n", output_file);
		close(ofd);
		}

		static void
usage(void)		usage(void)
{		{

printf("ucode-split [-v] microcode_file\n");		printf("ucode-split [-v] microcode_file\n");
exit(1);		exit(1);
}		}

int		int
main(int argc, char *argv[])		main(int argc, char *argv[])
{		{
struct microcode_update_header hdr;		struct microcode_update_header hdr;
		struct ucode_intel_extsig_table etbl;
		struct ucode_intel_extsig extsig;
char buf, output_file, *sig_str;		char buf, output_file, *sig_str;
size_t len, resid;		off_t entry_start;
		uint32_t data_size, total_size, i;
ssize_t rv;		ssize_t rv;
int c, ifd, ofd;		int c, ifd;
bool vflag;		bool vflag;

vflag = false;		vflag = false;
while ((c = getopt(argc, argv, "v")) != -1) {		while ((c = getopt(argc, argv, "v")) != -1) {
switch (c) {		switch (c) {
case 'v':		case 'v':
vflag = true;		vflag = true;
break;		break;
Show All 11 Lines	main(int argc, char *argv[])
if (ifd < 0)		if (ifd < 0)
err(1, "open");		err(1, "open");

buf = malloc(bufsize);		buf = malloc(bufsize);
if (buf == NULL)		if (buf == NULL)
err(1, "malloc");		err(1, "malloc");

for (;;) {		for (;;) {
		entry_start = lseek(ifd, 0, SEEK_CUR);
		if (entry_start < 0)
		err(1, "lseek");

/* Read header. */		/* Read header. */
rv = read(ifd, &hdr, sizeof(hdr));		rv = read(ifd, &hdr, sizeof(hdr));
if (rv < 0) {		if (rv < 0) {
err(1, "read");		err(1, "read");
} else if (rv == 0) {		} else if (rv == 0) {
break;		break;
} else if (rv < (ssize_t)sizeof(hdr)) {		} else if (rv < (ssize_t)sizeof(hdr)) {
errx(1, "invalid microcode header");		errx(1, "invalid microcode header");
}		}
if (hdr.header_version != 1)		if (hdr.header_version != 1)
errx(1, "invalid header version");		errx(1, "invalid header version");

if (vflag)		if (vflag)
dump_header(&hdr);		dump_header(&hdr);

		data_size = hdr.data_size != 0 ? hdr.data_size : 2000;
		total_size = hdr.total_size != 0 ? hdr.total_size : 2048;

		if (total_size - sizeof(hdr) > 1 << 24) /* Arbitrary chosen maximum size. */
		errx(1, "header total_size too large");

		/* Write primary output file. */
sig_str = format_signature(hdr.processor_signature);		sig_str = format_signature(hdr.processor_signature);
asprintf(&output_file, "%s.%02x", sig_str,		asprintf(&output_file, "%s.%02x", sig_str,
hdr.processor_flags & 0xff);		hdr.processor_flags & 0xff);
free(sig_str);		free(sig_str);
if (output_file == NULL)		if (output_file == NULL)
err(1, "asprintf");		err(1, "asprintf");
ofd = open(output_file, O_WRONLY \| O_CREAT \| O_TRUNC, 0600);		copy_entry(ifd, entry_start, total_size, output_file, buf, vflag);
if (ofd < 0)		free(output_file);
err(1, "open");

/* Write header. */		/*
rv = write(ofd, &hdr, sizeof(hdr));		* Process the extended signature table, if present. Each
if (rv < (ssize_t)sizeof(hdr))		* entry names an additional processor signature and platform
err(1, "write");		* flags combination covered by this microcode blob, so write
		* a copy of the blob for each one that differs from the
		* primary.
		*/
		if (total_size > data_size + sizeof(hdr)) {
		if (lseek(ifd, entry_start + sizeof(hdr) + data_size,
		SEEK_SET) < 0)
		err(1, "lseek");
		rv = read(ifd, &etbl, sizeof(etbl));
		if (rv < (ssize_t)sizeof(etbl))
		errx(1, "truncated extended signature table");
		markjUnsubmitted Not Done Inline Actions You might handle this error case in the same way as in copy_entry(), i.e., check for `rv < 0` separately so you can print errno. markj: You might handle this error case in the same way as in copy_entry(), i.e., check for `rv < 0`…

/* Copy data. */		for (i = 0; i < etbl.signature_count; i++) {
resid = (hdr.total_size != 0 ? hdr.total_size : 2048) -		rv = read(ifd, &extsig, sizeof(extsig));
sizeof(hdr);		if (rv < (ssize_t)sizeof(extsig))
		markjUnsubmitted Not Done Inline Actions Same here. markj: Same here.
if (resid > 1 << 24) /* Arbitrary chosen maximum size. */		errx(1, "truncated extended signature "
errx(1, "header total_size too large");		"entry %u", i);
while (resid > 0) {
len = resid < bufsize ? resid : bufsize;		if (extsig.processor_signature ==
rv = read(ifd, buf, len);		hdr.processor_signature &&
if (rv < 0)		extsig.processor_flags ==
err(1, "read");		hdr.processor_flags)
else if (rv < (ssize_t)len)		continue;
		markjUnsubmitted Not Done Inline Actions I'm not sure there's much point in skipping identical entries? copy_entry() will just overwrite the file again. markj: I'm not sure there's much point in skipping identical entries? copy_entry() will just overwrite…
errx(1, "truncated microcode data");
if (write(ofd, buf, len) < (ssize_t)len)		sig_str = format_signature(
err(1, "write");		extsig.processor_signature);
resid -= len;		asprintf(&output_file, "%s.%02x", sig_str,
		extsig.processor_flags & 0xff);
		free(sig_str);
		if (output_file == NULL)
		err(1, "asprintf");

		copy_entry(ifd, entry_start, total_size,
		output_file, buf, vflag);
		free(output_file);
		markjUnsubmitted Done Inline Actions Wouldn't it be simpler to make copy_entry() use pread(2)? markj: Wouldn't it be simpler to make copy_entry() use pread(2)?
		jrmAuthorUnsubmitted Done Inline Actions Indeed. Thanks. jrm: Indeed. Thanks.
}		}
		}

if (vflag)		if (vflag)
printf("written to %s\n\n", output_file);		printf("\n");
close(ofd);
free(output_file);		/* Advance to the next entry. */
		if (lseek(ifd, entry_start + total_size, SEEK_SET) < 0)
		err(1, "lseek");
}		}
		feee(buf);
		close(ifd);
}		}