1 files changed, 269 insertions, 84 deletions

diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c
index 35abbfae..12aabe4d 100644
--- a/util/nvmutil/nvmutil.c
+++ b/util/nvmutil/nvmutil.c
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT */
-/* SPDX-FileCopyrightText: 2022, 2023 Leah Rowe <leah@libreboot.org> */
-/* SPDX-FileCopyrightText: 2023 Riku Viitanen <riku.viitanen@protonmail.com> */
+/* Copyright (c) 2022-2025 Leah Rowe <leah@libreboot.org> */
+/* Copyright (c) 2023 Riku Viitanen <riku.viitanen@protonmail.com> */
 
 #include <sys/stat.h>
 
@@ -14,22 +14,31 @@
 #include <string.h>
 #include <unistd.h>
 
-void cmd_setchecksum(void), cmd_brick(void), cmd_copy(void), writeGbeFile(void),
-    cmd_dump(void), cmd_setmac(void), readGbeFile(void), showmac(int partnum),
-    hexdump(int partnum), handle_endianness(int partnum), openFiles(const char *path);
-int macAddress(const char *strMac, uint16_t *mac), validChecksum(int partnum);
+void cmd_setchecksum(void), cmd_brick(void), swap(int partnum), writeGbe(void),
+    cmd_dump(void), cmd_setmac(void), readGbe(void), checkdir(const char *path),
+    macf(int partnum), hexdump(int partnum), openFiles(const char *path),
+    cmd_copy(void), parseMacString(const char *strMac, uint16_t *mac),
+    cmd_swap(void);
+int goodChecksum(int partnum);
 uint8_t hextonum(char chs), rhex(void);
 
 #define COMMAND argv[2]
 #define MAC_ADDRESS argv[3]
-#define PARTNUM argv[3]
+#define PARTN argv[3]
+#define NVM_CHECKSUM 0xBABA
+#define NVM_CHECKSUM_WORD 0x3F
+#define NVM_SIZE 128
+
 #define SIZE_4KB 0x1000
+#define SIZE_8KB 0x2000
+#define SIZE_16KB 0x4000
+#define SIZE_128KB 0x20000
 
-uint16_t buf16[SIZE_4KB], mac[3] = {0, 0, 0};
-uint8_t *buf = (uint8_t *) &buf16;
-size_t nf = 128, gbe[2];
-uint8_t nvmPartModified[2] = {0, 0}, skipread[2] = {0, 0};
-int e = 1, flags = O_RDWR, rfd, fd, part, gbeFileModified = 0;
+uint16_t mac[3] = {0, 0, 0};
+ssize_t nf;
+size_t partsize, gbe[2];
+uint8_t nvmPartChanged[2] = {0, 0}, do_read[2] = {1, 1};
+int flags, rfd, fd, part;
 
 const char *strMac = NULL, *strRMac = "??:??:??:??:??:??", *filename = NULL;
 
@@ -41,7 +50,7 @@ typedef struct op {
 op_t op[] = {
 { .str = "dump", .cmd = cmd_dump, .args = 3},
 { .str = "setmac", .cmd = cmd_setmac, .args = 3},
-{ .str = "swap", .cmd = writeGbeFile, .args = 3},
+{ .str = "swap", .cmd = cmd_swap, .args = 3},
 { .str = "copy", .cmd = cmd_copy, .args = 4},
 { .str = "brick", .cmd = cmd_brick, .args = 4},
 { .str = "setchecksum", .cmd = cmd_setchecksum, .args = 4},
@@ -51,20 +60,29 @@ void (*cmd)(void) = NULL;
 #define ERR() errno = errno ? errno : ECANCELED
 #define err_if(x) if (x) err(ERR(), "%s", filename)
 
-#define xopen(f,l,p) if (opendir(l) != NULL) err(errno = EISDIR, "%s", l); \
-    if ((f = open(l, p)) == -1) err(ERR(), "%s", l); \
+#define xopen(f,l,p) if ((f = open(l, p)) == -1) err(ERR(), "%s", l); \
     if (fstat(f, &st) == -1) err(ERR(), "%s", l)
 
-#define word(pos16, partnum) buf16[pos16 + (partnum << 11)]
-#define setWord(pos16, p, val16) if ((gbeFileModified = 1) && \
-    word(pos16, p) != val16) nvmPartModified[p] = 1 | (word(pos16, p) = val16)
+#define word(pos16, partnum) ((uint16_t *) gbe[partnum])[pos16]
+#define setWord(pos16, p, val16) if (word(pos16, p) != val16) \
+    nvmPartChanged[p] = 1 | (word(pos16, p) = val16)
 
 int
 main(int argc, char *argv[])
 {
-	if (argc < 3) {
+#ifdef __OpenBSD__
+	err_if(pledge("stdio rpath wpath unveil", NULL) == -1);
+#endif
+
+	if (argc < 2) {
+#ifdef __OpenBSD__
+		err_if(pledge("stdio", NULL) == -1);
+#endif
+		fprintf(stderr, "Modify Intel GbE NVM images e.g. set MAC\n");
 		fprintf(stderr, "USAGE:\n");
 		fprintf(stderr, " %s FILE dump\n", argv[0]);
+		fprintf(stderr, " %s FILE\n # same as setmac without arg\n",
+		    argv[0]);
 		fprintf(stderr, " %s FILE setmac [MAC]\n", argv[0]);
 		fprintf(stderr, " %s FILE swap\n", argv[0]);
 		fprintf(stderr, " %s FILE copy 0|1\n", argv[0]);
@@ -72,100 +90,207 @@ main(int argc, char *argv[])
 		fprintf(stderr, " %s FILE setchecksum 0|1\n", argv[0]);
 		err(errno = ECANCELED, "Too few arguments");
 	}
-	flags = (strcmp(COMMAND, "dump") == 0) ? O_RDONLY : flags;
+
 	filename = argv[1];
+
+	flags = O_RDWR;
+
+	if (argc > 2) {
+		if (strcmp(COMMAND, "dump") == 0) {
+			flags = O_RDONLY;
+#ifdef __OpenBSD__
+			err_if(pledge("stdio rpath unveil", NULL) == -1);
+#endif
+		}
+	}
+
+	checkdir("/dev/urandom");
+	checkdir(filename);
+
 #ifdef __OpenBSD__
 	err_if(unveil("/dev/urandom", "r") == -1);
-	err_if(unveil(filename, flags == O_RDONLY ? "r" : "rw") == -1);
-	err_if(pledge(flags == O_RDONLY ? "stdio rpath" : "stdio rpath wpath",
-	    NULL) == -1);
+
+	if (flags == O_RDONLY) {
+		err_if(unveil(filename, "r") == -1);
+		err_if(unveil(NULL, NULL) == -1);
+		err_if(pledge("stdio rpath", NULL) == -1);
+	} else {
+		err_if(unveil(filename, "rw") == -1);
+		err_if(unveil(NULL, NULL) == -1);
+		err_if(pledge("stdio rpath wpath", NULL) == -1);
+	}
 #endif
+
 	openFiles(filename);
 #ifdef __OpenBSD__
 	err_if(pledge("stdio", NULL) == -1);
 #endif
 
-	for (int i = 0; i < 6; i++)
-		if (strcmp(COMMAND, op[i].str) == 0)
-			if ((cmd = argc >= op[i].args ? op[i].cmd : NULL))
+	if (argc > 2) {
+		for (int i = 0; (i < 6) && (cmd == NULL); i++) {
+			if (strcmp(COMMAND, op[i].str) != 0)
+				continue;
+			if (argc >= op[i].args) {
+				cmd = op[i].cmd;
 				break;
-	if (cmd == cmd_setmac)
-		strMac = (argc > 3) ? MAC_ADDRESS : strRMac;
-	else if ((cmd != NULL) && (argc > 3))
-		err_if((errno = (!((part = PARTNUM[0] - '0') == 0 || part == 1))
-		    || PARTNUM[1] ? EINVAL : errno));
+			}
+			err(errno = EINVAL, "Too few args on command '%s'",
+			    op[i].str);
+		}
+	} else {
+		cmd = cmd_setmac;
+	}
+
+	if ((cmd == NULL) && (argc > 2)) { /* nvm gbe [MAC] */
+		strMac = COMMAND;
+		cmd = cmd_setmac;
+	} else if (cmd == cmd_setmac) { /* nvm gbe setmac [MAC] */
+		strMac = strRMac; /* random MAC */
+		if (argc > 3)
+			strMac = MAC_ADDRESS;
+	} else if ((cmd != NULL) && (argc > 3)) { /* user-supplied partnum */
+		err_if((errno = (!((part = PARTN[0] - '0') == 0 || part == 1))
+		    || PARTN[1] ? EINVAL : errno)); /* only allow '0' or '1' */
+	}
 	err_if((errno = (cmd == NULL) ? EINVAL : errno));
 
-	readGbeFile();
+	readGbe();
 	(*cmd)();
+	writeGbe();
 
-	if ((gbeFileModified) && (flags != O_RDONLY) && (cmd != writeGbeFile))
-		writeGbeFile();
 	err_if((errno != 0) && (cmd != cmd_dump));
 	return errno;
 }
 
 void
+checkdir(const char *path)
+{
+	if (opendir(path) != NULL)
+		err(errno = EISDIR, "%s", path);
+	if (errno == ENOTDIR)
+		errno = 0;
+	err_if(errno);
+}
+
+void
 openFiles(const char *path)
 {
 	struct stat st;
+
 	xopen(fd, path, flags);
-	if ((st.st_size != (SIZE_4KB << 1)))
-		err(errno = ECANCELED, "File `%s` not 8KiB", path);
+
+	switch(st.st_size) {
+	case SIZE_8KB:
+	case SIZE_16KB:
+	case SIZE_128KB:
+		partsize = st.st_size >> 1;
+		break;
+	default:
+		err(errno = ECANCELED, "Invalid file size (not 8/16/128KiB)");
+		break;
+	}
+
 	xopen(rfd, "/dev/urandom", O_RDONLY);
-	errno = errno != ENOTDIR ? errno : 0;
 }
 
 void
-readGbeFile(void)
+readGbe(void)
 {
-	nf = ((cmd == writeGbeFile) || (cmd == cmd_copy)) ? SIZE_4KB : nf;
-	skipread[part ^ 1] = (cmd == cmd_copy) | (cmd == cmd_setchecksum)
-	    | (cmd == cmd_brick);
-	gbe[1] = (gbe[0] = (size_t) buf) + SIZE_4KB;
+	if ((cmd == cmd_swap) || (cmd == cmd_copy))
+		nf = SIZE_4KB;
+	else
+		nf = NVM_SIZE;
+
+	if ((cmd == cmd_copy) || (cmd == cmd_setchecksum) || (cmd == cmd_brick))
+		do_read[part ^ 1] = 0;
+
+	char *buf = malloc(nf << (do_read[0] & do_read[1]));
+	if (buf == NULL)
+		err(errno, NULL);
+
+	gbe[0] = (size_t) buf;
+	gbe[1] = gbe[0] + (nf * (do_read[0] & do_read[1]));
+
+	ssize_t tnr = 0;
+
 	for (int p = 0; p < 2; p++) {
-		if (skipread[p])
+		if (!do_read[p])
 			continue;
-		err_if(pread(fd, (uint8_t *) gbe[p], nf, p << 12) == -1);
-		handle_endianness(p);
+
+		ssize_t nr = pread(fd, (uint8_t *) gbe[p], nf, p * partsize);
+		err_if(nr == -1);
+		if (nr != nf)
+			err(errno == ECANCELED,
+			    "%ld bytes read from '%s', expected %ld bytes\n",
+			    nr, filename, nf);
+
+		tnr += nr;
+		swap(p); /* handle big-endian host CPU */
 	}
+
+	printf("%ld bytes read from file '%s'\n", tnr, filename);
 }
 
 void
 cmd_setmac(void)
 {
-	if (macAddress(strMac, mac))
-		err(errno = ECANCELED, "Bad MAC address");
+	int mac_updated = 0;
+	parseMacString(strMac, mac);
+
+	printf("MAC address to be written: %s\n", strMac);
+
 	for (int partnum = 0; partnum < 2; partnum++) {
-		if (!validChecksum(part = partnum))
+		if (!goodChecksum(part = partnum))
 			continue;
+
 		for (int w = 0; w < 3; w++)
 			setWord(w, partnum, mac[w]);
+
+		printf("Wrote MAC address to part %d: ", partnum);
+		macf(partnum);
+
 		cmd_setchecksum();
+		mac_updated = 1;
 	}
+
+	if (mac_updated)
+		errno = 0;
 }
 
-int
-macAddress(const char *strMac, uint16_t *mac)
+void
+parseMacString(const char *strMac, uint16_t *mac)
 {
 	uint64_t total = 0;
-	if (strnlen(strMac, 20) == 17) {
+	if (strnlen(strMac, 20) != 17)
+		err(errno = EINVAL, "Invalid MAC address string length");
+
 	for (uint8_t h, i = 0; i < 16; i += 3) {
 		if (i != 15)
 			if (strMac[i + 2] != ':')
-				return 1;
+				err(errno = EINVAL,
+				    "Invalid MAC address separator '%c'",
+				    strMac[i + 2]);
+
 		int byte = i / 3;
+
 		for (int nib = 0; nib < 2; nib++, total += h) {
 			if ((h = hextonum(strMac[i + nib])) > 15)
-				return 1;
+				err(errno = EINVAL, "Invalid character '%c'",
+				    strMac[i + nib]);
+
 			if ((byte == 0) && (nib == 1))
-				if (strMac[i + nib] == '?')
+				if (strMac[i + nib] == '?') /* ?=random */
 					h = (h & 0xE) | 2; /* local, unicast */
+
 			mac[byte >> 1] |= ((uint16_t ) h)
 			    << ((8 * (byte % 2)) + (4 * (nib ^ 1)));
 		}
-	}}
-	return ((total == 0) | (mac[0] & 1)); /* multicast/all-zero banned */
+	}
+
+	if (total == 0)
+		err(errno = EINVAL, "Invalid MAC (all-zero MAC address)");
+	if (mac[0] & 1)
+		err(errno = EINVAL, "Invalid MAC (multicast bit set)");
 }
 
 uint8_t
@@ -193,21 +318,32 @@ void
 cmd_dump(void)
 {
 	for (int partnum = 0, numInvalid = 0; partnum < 2; partnum++) {
-		if (!validChecksum(partnum))
+		if ((cmd != cmd_dump) && (flags != O_RDONLY) &&
+		    (!nvmPartChanged[partnum]))
+			continue;
+
+		if (!goodChecksum(partnum))
 			++numInvalid;
+
 		printf("MAC (part %d): ", partnum);
-		showmac(partnum), hexdump(partnum);
-		errno = ((numInvalid < 2) && (partnum)) ? 0 : errno;
+		macf(partnum);
+		hexdump(partnum);
+
+		if ((numInvalid < 2) && (partnum))
+			errno = 0;
 	}
 }
 
 void
-showmac(int partnum)
+macf(int partnum)
 {
 	for (int c = 0; c < 3; c++) {
 		uint16_t val16 = word(c, partnum);
 		printf("%02x:%02x", val16 & 0xff, val16 >> 8);
-		printf(c == 2 ? "\n" : ":");
+		if (c == 2)
+			printf("\n");
+		else
+			printf(":");
 	}
 }
 
@@ -215,11 +351,14 @@ void
 hexdump(int partnum)
 {
 	for (int row = 0; row < 8; row++) {
-		printf("%07x", row << 4);
+		printf("%08x ", row << 4);
 		for (int c = 0; c < 8; c++) {
 			uint16_t val16 = word((row << 3) + c, partnum);
-			printf(" %02x%02x", val16 >> 8, val16 & 0xff);
-		} printf("\n");
+			if (c == 4)
+				printf(" ");
+			printf(" %02x %02x", val16 & 0xff, val16 >> 8);
+		}
+		printf("\n");
 	}
 }
 
@@ -227,55 +366,101 @@ void
 cmd_setchecksum(void)
 {
 	uint16_t val16 = 0;
-	for (int c = 0; c < 0x3F; c++)
+	for (int c = 0; c < NVM_CHECKSUM_WORD; c++)
 		val16 += word(c, part);
-	setWord(0x3F, part, 0xBABA - val16);
+
+	setWord(NVM_CHECKSUM_WORD, part, NVM_CHECKSUM - val16);
 }
 
 void
 cmd_brick(void)
 {
-	if (validChecksum(part))
-		setWord(0x3F, part, ((word(0x3F, part)) ^ 0xFF));
+	if (goodChecksum(part))
+		setWord(NVM_CHECKSUM_WORD, part,
+		    ((word(NVM_CHECKSUM_WORD, part)) ^ 0xFF));
 }
 
 void
 cmd_copy(void)
 {
-	if ((gbeFileModified = nvmPartModified[part ^ 1] = validChecksum(part)))
-		gbe[part ^ 1] = gbe[part]; /* speedhack: copy ptr, not words */
+	nvmPartChanged[part ^ 1] = goodChecksum(part);
+}
+
+void
+cmd_swap(void) {
+	err_if(!(goodChecksum(0) || goodChecksum(1)));
+	errno = 0;
+
+	gbe[0] ^= gbe[1];
+	gbe[1] ^= gbe[0];
+	gbe[0] ^= gbe[1];
+
+	nvmPartChanged[0] = nvmPartChanged[1] = 1;
 }
 
 int
-validChecksum(int partnum)
+goodChecksum(int partnum)
 {
 	uint16_t total = 0;
-	for(int w = 0; w <= 0x3F; w++)
+	for(int w = 0; w <= NVM_CHECKSUM_WORD; w++)
 		total += word(w, partnum);
-	if (total == 0xBABA)
+
+	if (total == NVM_CHECKSUM)
 		return 1;
+
 	fprintf(stderr, "WARNING: BAD checksum in part %d\n", partnum);
-	return (errno = ECANCELED) & 0;
+	errno = ECANCELED;
+	return 0;
 }
 
 void
-writeGbeFile(void)
+writeGbe(void)
 {
-	err_if((cmd == writeGbeFile) && !(validChecksum(0) || validChecksum(1)));
-	for (int p = 0, x = (cmd == writeGbeFile) ? 1 : 0; p < 2; p++) {
-		if ((!nvmPartModified[p]) && (cmd != writeGbeFile))
+	ssize_t tnw = 0;
+
+	for (int p = 0; p < 2; p++) {
+		if ((!nvmPartChanged[p]) || (flags == O_RDONLY))
 			continue;
-		handle_endianness(p^x);
-		err_if(pwrite(fd, (uint8_t *) gbe[p^x], nf, p << 12) == -1);
+
+		swap(p); /* swap bytes on big-endian host CPUs */
+		ssize_t nw = pwrite(fd, (uint8_t *) gbe[p], nf, p * partsize);
+		err_if(nw == -1);
+		if (nw != nf)
+			err(errno == ECANCELED,
+			    "%ld bytes written to '%s', expected %ld bytes\n",
+			    nw, filename, nf);
+
+		tnw += nf;
 	}
-	errno = 0;
+
+	if ((flags != O_RDONLY) && (cmd != cmd_dump)) {
+		if (nvmPartChanged[0] || nvmPartChanged[1])
+			printf("The following nvm words were written:\n");
+		cmd_dump();
+	}
+
+	if ((!tnw) && (flags != O_RDONLY) && (!errno))
+		fprintf(stderr, "No changes needed on file '%s'\n", filename);
+	else if (tnw)
+		printf("%ld bytes written to file '%s'\n", tnw, filename);
+
+	if (tnw)
+		errno = 0;
+
 	err_if(close(fd) == -1);
 }
 
 void
-handle_endianness(int partnum)
+swap(int partnum)
 {
+	size_t w, x;
 	uint8_t *n = (uint8_t *) gbe[partnum];
-	for (size_t w = nf * ((uint8_t *) &e)[0], x = 1; w < nf; w += 2, x += 2)
-		n[w] ^= n[x], n[x] ^= n[w], n[w] ^= n[x];
+	int e = 1;
+
+	for (w = NVM_SIZE * ((uint8_t *) &e)[0], x = 1; w < NVM_SIZE;
+	    w += 2, x += 2) {
+		n[w] ^= n[x];
+		n[x] ^= n[w];
+		n[w] ^= n[x];
+	}
 }