diff options
Diffstat (limited to 'util')
| -rw-r--r-- | util/nvmutil/nvmutil.c | 101 |
1 files changed, 49 insertions, 52 deletions
diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c index 03aa3c20..9959a1ab 100644 --- a/util/nvmutil/nvmutil.c +++ b/util/nvmutil/nvmutil.c @@ -100,6 +100,8 @@ static void open_gbe_file(void); static void xopen(int *fd, const char *path, int flags, struct stat *st); static void read_gbe_file(void); static void read_gbe_file_part(size_t part); +static ssize_t read_gbe_file_exact(int fd, void *buf, size_t len, + off_t off); static void read_checksums(void); static int good_checksum(size_t partnum); static void cmd_helper_setmac(void); @@ -110,8 +112,10 @@ static void set_mac_nib(size_t mac_str_pos, size_t mac_byte_pos, size_t mac_nib_pos); static uint16_t hextonum(char ch_s); static uint16_t rhex(void); -static ssize_t read_gbe_file_exact(int fd, void *buf, size_t len, - off_t off, const char *path, const char *op); +#ifndef NVMUTIL_ARC4RANDOM_BUF +static ssize_t read_dev_urandom(int fd, void *buf, + size_t len); +#endif static void write_mac_part(size_t partnum); static void cmd_helper_dump(void); static void print_mac_from_nvm(size_t partnum); @@ -713,7 +717,7 @@ read_gbe_file_part(size_t p) gbe_mem_offset(p ^ command[cmd_index].invert, "pread"); if ((size_t)read_gbe_file_exact(gbe_fd, mem_offset, - gbe_rw_size, gbe_file_offset(p, "pread"), fname, "pread") != + gbe_rw_size, gbe_file_offset(p, "pread")) != gbe_rw_size) err(ECANCELED, "%s: Partial read from p%zu", fname, p); @@ -721,6 +725,37 @@ read_gbe_file_part(size_t p) fname, gbe_rw_size, p); } +static ssize_t +read_gbe_file_exact(int fd, + void *buf, size_t len, off_t off) +{ + int retry; + ssize_t rval; + + if (fd == -1) + err(ECANCELED, "Trying to open bad fd: %s", fname); + + for (retry = 0; retry < MAX_RETRY_RW; retry++) { + rval = pread(fd, buf, len, off); + + if (rval == (ssize_t)len) { + errno = 0; + return rval; + } else if (rval != -1) { + err(ECANCELED, + "%s: Short pread of %zd bytes", + fname, rval); + } else if (errno != EINTR) { + err(ECANCELED, + "%s: Could not pread", fname); + } + } + + err(EINTR, "%s: pread: max retries exceeded", fname); + + return -1; +} + static void read_checksums(void) { @@ -930,82 +965,44 @@ rhex(void) { static size_t n = 0; static uint8_t rnum[12]; -#ifndef NVMUTIL_ARC4RANDOM_BUF - int max_retries; -#endif -#ifdef NVMUTIL_ARC4RANDOM_BUF if (!n) { +#ifdef NVMUTIL_ARC4RANDOM_BUF n = sizeof(rnum); arc4random_buf(rnum, n); - } #else - for (max_retries = 0; max_retries < 50 && !n; max_retries++) - n = (size_t)read_gbe_file_exact(urandom_fd, - rnum, sizeof(rnum), 0, rname, NULL); - if (!n || n > sizeof(rnum)) - err(ECANCELED, "Randomisation failure"); + n = (size_t)read_dev_urandom( + urandom_fd, rnum, sizeof(rnum)); #endif + } return (uint16_t)(rnum[--n] & 0xf); } +#ifndef NVMUTIL_ARC4RANDOM_BUF static ssize_t -read_gbe_file_exact(int fd, void *buf, size_t len, - off_t off, const char *path, const char *op) +read_dev_urandom(int fd, void *buf, size_t len) { int retry; ssize_t rval; if (fd == -1) - err(ECANCELED, "Trying to open bad fd: %s", path); + err(ECANCELED, "Trying to open bad fd: %s", rname); for (retry = 0; retry < MAX_RETRY_RW; retry++) { - if (op) - rval = pread(fd, buf, len, off); - else - rval = read(fd, buf, len); + rval = read(fd, buf, len); - if (rval == (ssize_t)len) { + if (rval && (size_t)rval <= len) { errno = 0; return rval; } - - if (rval != -1) { -#ifndef NVMUTIL_ARC4RANDOM_BUF - if (fd == urandom_fd) { - /* - * /dev/[u]random reads can still return - * partial reads legally, on some weird - * Unix systems (especially older ones). - * - * We use a circular buffer for random - * bytes in rhex(), so we can just use - * the smaller amount of bytes and call - * read_gbe_file_exact again if necessary. - */ - if (rval > 0) { - errno = 0; - return rval; - } - } -#endif - err(ECANCELED, - "Short %s, %zd bytes, on file: %s", - op ? op : "read", rval, path); - } - - if (errno != EINTR) - err(ECANCELED, - "Could not %s file: '%s'", - op ? op : "read", path); } - err(EINTR, "%s: max retries exceeded on file: %s", - op ? op : "read", path); + err(EINTR, "%s: read: max retries exceeded: %s", rname); return -1; } +#endif static void write_mac_part(size_t partnum) |