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-rw-r--r--util/nvmutil/.gitignore7
-rw-r--r--util/nvmutil/Makefile14
-rw-r--r--util/nvmutil/nvmutil.c604
3 files changed, 536 insertions, 89 deletions
diff --git a/util/nvmutil/.gitignore b/util/nvmutil/.gitignore
new file mode 100644
index 00000000..fbfbd130
--- /dev/null
+++ b/util/nvmutil/.gitignore
@@ -0,0 +1,7 @@
+/nvm
+/nvmutil
+/mkhtemp
+/lottery
+*.bin
+*.o
+*.d
diff --git a/util/nvmutil/Makefile b/util/nvmutil/Makefile
index b8ec2ad3..e8350203 100644
--- a/util/nvmutil/Makefile
+++ b/util/nvmutil/Makefile
@@ -3,22 +3,22 @@
# SPDX-FileCopyrightText: 2023 Riku Viitanen <riku.viitanen@protonmail.com>
CC?=cc
-CFLAGS?=-Os -Wall -Wextra -Werror -pedantic
+CFLAGS?=-Os -Wall -Wextra
DESTDIR?=
PREFIX?=/usr/local
INSTALL?=install
-nvm: nvmutil.c
- $(CC) $(CFLAGS) nvmutil.c -o nvm
+nvmutil: nvmutil.c
+ $(CC) $(CFLAGS) nvmutil.c -o nvmutil
install:
- $(INSTALL) nvm $(DESTDIR)$(PREFIX)/bin/nvm
+ $(INSTALL) nvmutil $(DESTDIR)$(PREFIX)/bin/nvmutil
uninstall:
- rm -f $(DESTDIR)$(PREFIX)/bin/nvm
+ rm -f $(DESTDIR)$(PREFIX)/bin/nvmutil
distclean:
- rm -f nvm
+ rm -f nvmutil
clean:
- rm -f nvm
+ rm -f nvmutil
diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c
index 68bb95da..1910c974 100644
--- a/util/nvmutil/nvmutil.c
+++ b/util/nvmutil/nvmutil.c
@@ -1,38 +1,66 @@
/* SPDX-License-Identifier: MIT */
-/* Copyright (c) 2022-2025 Leah Rowe <leah@libreboot.org> */
+/* Copyright (c) 2022-2026 Leah Rowe <leah@libreboot.org> */
/* Copyright (c) 2023 Riku Viitanen <riku.viitanen@protonmail.com> */
+#include <sys/types.h>
#include <sys/stat.h>
-#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
-#include <stdint.h>
+#include <stdarg.h>
+#include <stddef.h>
#include <stdio.h>
-#include <stdlib.h>
#include <string.h>
+#include <stdlib.h>
#include <unistd.h>
+#include <limits.h>
+#include <stdint.h>
void cmd_setchecksum(void), cmd_brick(void), swap(int partnum), writeGbe(void),
- cmd_dump(void), cmd_setmac(void), readGbe(void), cmd_copy(void),
- macf(int partnum), hexdump(int partnum), openFiles(const char *path);
-int macAddress(const char *strMac, uint16_t *mac), goodChecksum(int partnum);
+ cmd_dump(void), cmd_setmac(void), readGbe(void),
+ macf(int partnum), hexdump(int partnum), openFiles(const char *path),
+ cmd_copy(void), parseMacString(const char *strMac, uint16_t *mac),
+ cmd_swap(void), xclose(int *fd);
+int goodChecksum(int partnum), open_on_eintr(const char *pathname, int flags),
+ fs_retry(int saved_errno, int rval),
+ rw_retry(int saved_errno, ssize_t rval), if_err(int condition, int errval),
+ if_err_sys(int condition);
+ssize_t rw_exact(int fd, unsigned char *mem, size_t nrw,
+ off_t off, int rw_type);
+ssize_t rw(int fd, void *mem, size_t nrw,
+ off_t off, int rw_type);
+int io_args(int fd, void *mem, size_t nrw,
+ off_t off, int rw_type);
+int with_fallback_errno(int fallback);
+ssize_t rw_over_nrw(ssize_t r, size_t nrw);
uint8_t hextonum(char chs), rhex(void);
#define COMMAND argv[2]
#define MAC_ADDRESS argv[3]
#define PARTN argv[3]
-#define SIZE_4KB 0x1000
#define NVM_CHECKSUM 0xBABA
+#define NVM_CHECKSUM_WORD 0x3F
+#define NVM_SIZE 128
-uint16_t buf16[SIZE_4KB], mac[3] = {0, 0, 0};
-uint8_t *buf = (uint8_t *) &buf16;
-size_t nf = 128, gbe[2];
-uint8_t nvmPartChanged[2] = {0, 0}, skipread[2] = {0, 0};
-int e = 1, flags = O_RDWR, rfd, fd, part, gbeFileChanged = 0;
+#define SIZE_4KB 0x1000
+#define SIZE_8KB 0x2000
+#define SIZE_16KB 0x4000
+#define SIZE_128KB 0x20000
+
+#define IO_READ 0
+#define IO_WRITE 1
+#define IO_PREAD 2
+#define IO_PWRITE 3
+
+uint16_t mac[3] = {0, 0, 0};
+ssize_t nf;
+size_t partsize;
+uintptr_t 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;
+const char *strMac = NULL, *strRMac = "xx:xx:xx:xx:xx:xx", *filename = NULL;
typedef struct op {
char *str;
@@ -42,136 +70,271 @@ typedef struct op {
op_t op[] = {
{ .str = "dump", .cmd = cmd_dump, .args = 3},
{ .str = "setmac", .cmd = cmd_setmac, .args = 3},
-{ .str = "swap", .cmd = writeGbe, .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},
};
void (*cmd)(void) = NULL;
-#define ERR() errno = errno ? errno : ECANCELED
-#define err_if(x) if (x) err(ERR(), "%s", filename)
+#define err_if(x) if (x) err(EXIT_FAILURE, "%s", filename)
+
+#define xopen(f,l,p) \
+ do { \
+ if ((f = open_on_eintr(l, p)) == -1) \
+ err(EXIT_FAILURE, "%s", l); \
+ if (fstat(f, &st) == -1) \
+ err(EXIT_FAILURE, "%s", l); \
+ } while(0)
+
+#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)
-#define xopen(f,l,p) if (opendir(l) != NULL) err(errno = EISDIR, "%s", l); \
- if ((f = open(l, p)) == -1) err(ERR(), "%s", l); \
- if (fstat(f, &st) == -1) err(ERR(), "%s", l)
+#define SUCCESS(x) ((x) >= 0)
-#define word(pos16, partnum) buf16[pos16 + (partnum << 11)]
-#define setWord(pos16, p, val16) if ((gbeFileChanged = 1) && \
- word(pos16, p) != val16) nvmPartChanged[p] = 1 | (word(pos16, p) = val16)
+#define reset_caller_errno(return_value) \
+ do { \
+ if (SUCCESS(return_value) && (!errno)) \
+ errno = saved_errno; \
+ } while (0)
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]);
fprintf(stderr, " %s FILE brick 0|1\n", argv[0]);
fprintf(stderr, " %s FILE setchecksum 0|1\n", argv[0]);
- err(errno = ECANCELED, "Too few arguments");
+ errno = EINVAL;
+ err(EXIT_FAILURE, "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
+ }
+ }
+
#ifdef __OpenBSD__
err_if(unveil("/dev/urandom", "r") == -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))
+ }
+ errno = EINVAL;
+ err(EXIT_FAILURE, "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));
- err_if((errno = (cmd == NULL) ? EINVAL : errno));
+ || PARTN[1] ? EINVAL : 0)); /* only allow '0' or '1' */
+ }
+ if (cmd == NULL) {
+ errno = EINVAL;
+ err(EXIT_FAILURE, "Bad command");
+ }
readGbe();
(*cmd)();
+ writeGbe();
- if ((gbeFileChanged) && (flags != O_RDONLY) && (cmd != writeGbe))
- writeGbe();
- err_if((errno != 0) && (cmd != cmd_dump));
- return errno;
+ return EXIT_SUCCESS;
}
void
openFiles(const char *path)
{
struct stat st;
+
+ xopen(rfd, "/dev/urandom", O_RDONLY);
xopen(fd, path, flags);
- if ((st.st_size != (SIZE_4KB << 1)))
- err(errno = ECANCELED, "File `%s` not 8KiB", path);
- xopen(rfd, "/dev/urandom", O_RDONLY);
- errno = errno != ENOTDIR ? errno : 0;
+
+ switch(st.st_size) {
+ case SIZE_8KB:
+ case SIZE_16KB:
+ case SIZE_128KB:
+ partsize = st.st_size >> 1;
+ break;
+ default:
+ errno = ECANCELED;
+ err(EXIT_FAILURE, "Invalid file size (not 8/16/128KiB)");
+ break;
+ }
+
+ if (if_err(!S_ISREG(st.st_mode), EBADF))
+ err(EXIT_FAILURE, "Not a GbE file");
}
void
readGbe(void)
{
- nf = ((cmd == writeGbe) || (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(EXIT_FAILURE, "malloc");
+
+ gbe[0] = (uintptr_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);
- swap(p);
+
+ ssize_t nr = rw_exact(fd, (uint8_t *) gbe[p],
+ nf, p * partsize, IO_PREAD);
+ err_if(nr == -1);
+ if (nr != nf)
+ err(EXIT_FAILURE,
+ "%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 (!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)
+ return;
+
+ errno = EINVAL;
+ err(EXIT_FAILURE, "Error updating MAC address");
}
-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) {
+ errno = EINVAL;
+ err(EXIT_FAILURE, "Invalid MAC address string length");
+ }
+
for (uint8_t h, i = 0; i < 16; i += 3) {
if (i != 15)
- if (strMac[i + 2] != ':')
- return 1;
+ if (strMac[i + 2] != ':') {
+ errno = EINVAL;
+ err(EXIT_FAILURE,
+ "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;
+ if ((h = hextonum(strMac[i + nib])) > 15) {
+ errno = EINVAL;
+ err(EXIT_FAILURE, "Invalid character '%c'",
+ strMac[i + nib]);
+ }
+
+ /* If random, ensure that local/unicast bits are set */
if ((byte == 0) && (nib == 1))
- if (strMac[i + nib] == '?')
+ if ((strMac[i + nib] == '?') ||
+ (strMac[i + nib] == 'x') ||
+ (strMac[i + nib] == 'X')) /* 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) || (mac[0] & 1)))
+ return;
+
+ errno = EINVAL;
+
+ if (total == 0)
+ err(EXIT_FAILURE, "Invalid MAC (all-zero MAC address)");
+ if (mac[0] & 1)
+ err(EXIT_FAILURE, "Invalid MAC (multicast bit set)");
}
uint8_t
@@ -183,7 +346,10 @@ hextonum(char ch)
return ch - 'A' + 10;
else if ((ch >= 'a') && (ch <= 'f'))
return ch - 'a' + 10;
- return (ch == '?') ? rhex() : 16;
+ else if ((ch == '?') || (ch == 'x') || (ch == 'X'))
+ return rhex(); /* random hex value */
+ else
+ return 16; /* error: invalid character */
}
uint8_t
@@ -191,7 +357,8 @@ rhex(void)
{
static uint8_t n = 0, rnum[16];
if (!n)
- err_if(pread(rfd, (uint8_t *) &rnum, (n = 15) + 1, 0) == -1);
+ err_if(rw_exact(rfd, (uint8_t *) &rnum,
+ (n = 15) + 1, 0, IO_READ) == -1);
return rnum[n--] & 0xf;
}
@@ -199,11 +366,16 @@ void
cmd_dump(void)
{
for (int partnum = 0, numInvalid = 0; partnum < 2; partnum++) {
+ if ((cmd != cmd_dump) && (flags != O_RDONLY) &&
+ (!nvmPartChanged[partnum]))
+ continue;
+
if (!goodChecksum(partnum))
++numInvalid;
+
printf("MAC (part %d): ", partnum);
- macf(partnum), hexdump(partnum);
- errno = ((numInvalid < 2) && (partnum)) ? 0 : errno;
+ macf(partnum);
+ hexdump(partnum);
}
}
@@ -213,7 +385,10 @@ 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(":");
}
}
@@ -227,7 +402,8 @@ hexdump(int partnum)
if (c == 4)
printf(" ");
printf(" %02x %02x", val16 & 0xff, val16 >> 8);
- } printf("\n");
+ }
+ printf("\n");
}
}
@@ -235,49 +411,114 @@ 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, NVM_CHECKSUM - val16);
+
+ setWord(NVM_CHECKSUM_WORD, part, NVM_CHECKSUM - val16);
}
void
cmd_brick(void)
{
if (goodChecksum(part))
- setWord(0x3F, part, ((word(0x3F, part)) ^ 0xFF));
+ setWord(NVM_CHECKSUM_WORD, part,
+ ((word(NVM_CHECKSUM_WORD, part)) ^ 0xFF));
}
void
cmd_copy(void)
{
- if ((gbeFileChanged = nvmPartChanged[part ^ 1] = goodChecksum(part)))
- gbe[part ^ 1] = gbe[part]; /* speedhack: copy ptr, not words */
+ nvmPartChanged[part ^ 1] = goodChecksum(part);
+}
+
+void
+cmd_swap(void) {
+ if(!(goodChecksum(0) || goodChecksum(1))) {
+ errno = EINVAL;
+ err(EXIT_FAILURE, "Invalid checksums");
+ }
+
+ gbe[0] ^= gbe[1];
+ gbe[1] ^= gbe[0];
+ gbe[0] ^= gbe[1];
+
+ nvmPartChanged[0] = nvmPartChanged[1] = 1;
}
int
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 == NVM_CHECKSUM)
return 1;
+
fprintf(stderr, "WARNING: BAD checksum in part %d\n", partnum);
- return (errno = ECANCELED) & 0;
+ return 0;
}
void
writeGbe(void)
{
- err_if((cmd == writeGbe) && !(goodChecksum(0) || goodChecksum(1)));
- for (int p = 0, x = (cmd == writeGbe) ? 1 : 0; p < 2; p++) {
- if ((!nvmPartChanged[p]) && (cmd != writeGbe))
+ ssize_t tnw = 0;
+
+ for (int p = 0; p < 2; p++) {
+ if ((!nvmPartChanged[p]) || (flags == O_RDONLY))
continue;
- swap(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 = rw_exact(fd, (uint8_t *) gbe[p], nf,
+ p * partsize, IO_PWRITE);
+ err_if(nw == -1);
+ if (nw != nf) {
+ errno = ECANCELED;
+ err(EXIT_FAILURE,
+ "%ld bytes written to '%s', expected %ld bytes\n",
+ nw, filename, nf);
+ }
+
+ tnw += nf;
}
+
+ 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))
+ fprintf(stderr, "No changes needed on file '%s'\n", filename);
+ else if (tnw)
+ printf("%ld bytes written to file '%s'\n", tnw, filename);
+
+ xclose(&fd);
+}
+
+void
+xclose(int *fd)
+{
+ int saved_errno = errno;
+ int rval = 0;
+
+ if (fd == NULL)
+ err(EXIT_FAILURE, "xclose: null pointer");
+ if (*fd < 0)
+ return;
+
errno = 0;
- err_if(close(fd) == -1);
+ if ((rval = close(*fd)) < 0) {
+ if (errno != EINTR)
+ err(EXIT_FAILURE, "xclose: could not close");
+
+ /* regard EINTR as a successful close */
+ rval = 0;
+ }
+
+ *fd = -1;
+
+ reset_caller_errno(rval);
}
void
@@ -285,6 +526,205 @@ swap(int partnum)
{
size_t w, x;
uint8_t *n = (uint8_t *) gbe[partnum];
- for (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];
+ }
+}
+
+int
+open_on_eintr(const char *pathname,
+ int flags)
+{
+ int saved_errno = errno;
+ int rval = 0;
+ errno = 0;
+
+ while (fs_retry(saved_errno,
+ rval = open(pathname, flags)));
+
+ reset_caller_errno(rval);
+ return rval;
+}
+
+
+ssize_t
+rw_exact(int fd, unsigned char *mem, size_t nrw,
+ off_t off, int rw_type)
+{
+ int saved_errno = errno;
+ ssize_t rval = 0;
+ ssize_t rc = 0;
+ size_t nrw_cur;
+ off_t off_cur;
+ void *mem_cur;
+ errno = 0;
+
+ if (io_args(fd, mem, nrw, off, rw_type) == -1)
+ goto err_rw_exact;
+
+ while (1) {
+
+ /* Prevent theoretical overflow */
+ if (if_err(rval >= 0 && (size_t)rval > (nrw - (size_t)rc),
+ EOVERFLOW))
+ goto err_rw_exact;
+
+ rc += rval;
+ if ((size_t)rc >= nrw)
+ break;
+
+ mem_cur = (void *)(mem + (size_t)rc);
+ nrw_cur = (size_t)(nrw - (size_t)rc);
+
+ if (if_err(off < 0, EOVERFLOW))
+ goto err_rw_exact;
+
+ off_cur = off + (off_t)rc;
+
+ if ((rval = rw(fd, mem_cur, nrw_cur, off_cur, rw_type)) <= 0)
+ goto err_rw_exact;
+ }
+
+ if (if_err((size_t)rc != nrw, EIO) ||
+ (rval = rw_over_nrw(rc, nrw)) < 0)
+ goto err_rw_exact;
+
+ reset_caller_errno(rval);
+ return rval;
+
+err_rw_exact:
+ return with_fallback_errno(EIO);
+}
+
+ssize_t
+rw(int fd, void *mem, size_t nrw,
+ off_t off, int rw_type)
+{
+ ssize_t rval = 0;
+ ssize_t r = -1;
+ int saved_errno = errno;
+ errno = 0;
+
+ if (io_args(fd, mem, nrw, off, rw_type) == -1 ||
+ if_err(mem == NULL, EFAULT) ||
+ if_err(fd < 0, EBADF) ||
+ if_err(off < 0, EFAULT) ||
+ if_err(nrw == 0, EINVAL))
+ return with_fallback_errno(EIO);
+
+ do {
+ switch (rw_type) {
+ case IO_READ:
+ r = read(fd, mem, nrw);
+ break;
+ case IO_WRITE:
+ r = write(fd, mem, nrw);
+ break;
+ case IO_PREAD:
+ r = pread(fd, mem, nrw, off);
+ break;
+ case IO_PWRITE:
+ r = pwrite(fd, mem, nrw, off);
+ break;
+ default:
+ errno = EINVAL;
+ break;
+ }
+
+ } while (rw_retry(saved_errno, r));
+
+ if ((rval = rw_over_nrw(r, nrw)) < 0)
+ return with_fallback_errno(EIO);
+
+ reset_caller_errno(rval);
+ return rval;
+}
+
+int
+io_args(int fd, void *mem, size_t nrw,
+ off_t off, int rw_type)
+{
+ int saved_errno = errno;
+ errno = 0;
+
+ if (if_err(mem == NULL, EFAULT) ||
+ if_err(fd < 0, EBADF) ||
+ if_err(off < 0, ERANGE) ||
+ if_err(!nrw, EPERM) || /* TODO: toggle zero-byte check */
+ if_err(nrw > (size_t)SSIZE_MAX, ERANGE) ||
+ if_err(((size_t)off + nrw) < (size_t)off, ERANGE) ||
+ if_err(rw_type > IO_PWRITE, EINVAL))
+ goto err_io_args;
+
+ reset_caller_errno(0);
+ return 0;
+
+err_io_args:
+ return with_fallback_errno(EINVAL);
+}
+
+ssize_t
+rw_over_nrw(ssize_t r, size_t nrw)
+{
+ if (if_err(!nrw, EIO) ||
+ (r == -1) ||
+ if_err((size_t)r > SSIZE_MAX, ERANGE) ||
+ if_err((size_t)r > nrw, ERANGE))
+ return with_fallback_errno(EIO);
+
+ return r;
+}
+
+int
+with_fallback_errno(int fallback)
+{
+ if (!errno)
+ errno = fallback;
+ return -1;
+}
+
+/* two functions that reduce sloccount by
+ * two hundred lines */
+int
+if_err(int condition, int errval)
+{
+ if (!condition)
+ return 0;
+ if (errval)
+ errno = errval;
+ return 1;
+}
+int
+if_err_sys(int condition)
+{
+ if (!condition)
+ return 0;
+ return 1;
+}
+
+#define fs_err_retry() \
+ do { \
+ if ((rval == -1) && \
+ (errno == EINTR)) \
+ return 1; \
+ if (rval >= 0 && !errno) \
+ errno = saved_errno; \
+ return 0; \
+ } while(0)
+
+int
+fs_retry(int saved_errno, int rval)
+{
+ fs_err_retry();
+}
+
+int
+rw_retry(int saved_errno, ssize_t rval)
+{
+ fs_err_retry();
}
generated by cgit v1.2.1 (git 2.18.0) at 2026-04-23 04:38:26 +0000