Since it is quite cumbersome to manually create a combined kernel with
initrd image for network booting, we now support loading via pxelinux
configuration files, too. In these files, the kernel, initrd and command
line parameters can be specified seperately, and the firmware then takes
care of glueing everything together in memory after the files have been
downloaded.
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
pc-bios/s390-ccw/netboot.mak | 5 +-
pc-bios/s390-ccw/netmain.c | 203 +++++++++++++++++++++++++++++++++++++++++--
2 files changed, 201 insertions(+), 7 deletions(-)
diff --git a/pc-bios/s390-ccw/netboot.mak b/pc-bios/s390-ccw/netboot.mak
index a25d238..8db9573 100644
--- a/pc-bios/s390-ccw/netboot.mak
+++ b/pc-bios/s390-ccw/netboot.mak
@@ -24,8 +24,9 @@ CTYPE_OBJS = isdigit.o isxdigit.o toupper.o
%.o : $(SLOF_DIR)/lib/libc/ctype/%.c
$(call quiet-command,$(CC) $(LIBC_CFLAGS) -c -o $@ $<,"CC","$(TARGET_DIR)$@")
-STRING_OBJS = strcat.o strchr.o strcmp.o strcpy.o strlen.o strncmp.o strncpy.o \
- strstr.o memset.o memcpy.o memmove.o memcmp.o
+STRING_OBJS = strcasecmp.o strcat.o strchr.o strcmp.o strcpy.o strlen.o \
+ strncasecmp.o strncmp.o strncpy.o strstr.o \
+ memset.o memcpy.o memmove.o memcmp.o
%.o : $(SLOF_DIR)/lib/libc/string/%.c
$(call quiet-command,$(CC) $(LIBC_CFLAGS) -c -o $@ $<,"CC","$(TARGET_DIR)$@")
diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
index e11ed4e..fa62bfe 100644
--- a/pc-bios/s390-ccw/netmain.c
+++ b/pc-bios/s390-ccw/netmain.c
@@ -39,11 +39,17 @@
extern char _start[];
+#define KERNEL_ADDR ((void *)0L)
+#define KERNEL_MAX_SIZE ((long)_start)
+#define ARCH_COMMAND_LINE_SIZE 896 /* Taken from Linux kernel */
+
char stack[PAGE_SIZE * 8] __attribute__((aligned(PAGE_SIZE)));
IplParameterBlock iplb __attribute__((aligned(PAGE_SIZE)));
+static char cfgbuf[2048];
static SubChannelId net_schid = { .one = 1 };
static int ip_version = 4;
+static uint8_t mac[6];
static uint64_t dest_timer;
static uint64_t get_timer_ms(void)
@@ -136,9 +142,15 @@ static int tftp_load(filename_ip_t *fnip, void *buffer, int len)
rc = tftp(fnip, buffer, len, DEFAULT_TFTP_RETRIES, &tftp_err, 1, 1428,
ip_version);
- if (rc > 0) {
- printf(" TFTP: Received %s (%d KBytes)\n", fnip->filename,
- rc / 1024);
+ if (rc < 0) {
+ /* Make sure that error messages are put into a new line */
+ printf("\n ");
+ }
+
+ if (rc > 1024) {
+ printf(" TFTP: Received %s (%d KBytes)\n", fnip->filename, rc / 1024);
+ } else if (rc > 0) {
+ printf(" TFTP: Received %s (%d Bytes)\n", fnip->filename, rc);
} else if (rc == -1) {
puts("unknown TFTP error");
} else if (rc == -2) {
@@ -201,7 +213,6 @@ static int tftp_load(filename_ip_t *fnip, void *buffer, int len)
static int net_init(filename_ip_t *fn_ip)
{
- uint8_t mac[6];
int rc;
memset(fn_ip, 0, sizeof(filename_ip_t));
@@ -276,6 +287,183 @@ static void net_uninit(filename_ip_t *fn_ip)
virtio_net_uninit();
}
+/* This structure holds the data from one pxelinux.cfg file entry */
+struct lkia {
+ const char *label;
+ const char *kernel;
+ const char *initrd;
+ const char *append;
+};
+
+static int load_kernel_with_initrd(filename_ip_t *fn_ip, struct lkia *kia)
+{
+ int rc;
+
+ printf("Loading pxelinux.cfg entry '%s'\n", kia->label);
+
+ if (!kia->kernel) {
+ printf("Kernel entry is missing!\n");
+ return -1;
+ }
+
+ strncpy((char *)&fn_ip->filename, kia->kernel, sizeof(fn_ip->filename));
+ rc = tftp_load(fn_ip, KERNEL_ADDR, KERNEL_MAX_SIZE);
+ if (rc < 0) {
+ return rc;
+ }
+
+ if (kia->initrd) {
+ uint64_t iaddr = (rc + 0xfff) & ~0xfffUL;
+
+ strncpy((char *)&fn_ip->filename, kia->initrd, sizeof(fn_ip->filename));
+ rc = tftp_load(fn_ip, (void *)iaddr, KERNEL_MAX_SIZE - iaddr);
+ if (rc < 0) {
+ return rc;
+ }
+ /* Patch location and size: */
+ *(uint64_t *)0x10408 = iaddr;
+ *(uint64_t *)0x10410 = rc;
+ rc += iaddr;
+ }
+
+ if (kia->append) {
+ strncpy((char *)0x10480, kia->append, ARCH_COMMAND_LINE_SIZE);
+ }
+
+ return rc;
+}
+
+#define MAX_PXELINUX_ENTRIES 16
+
+/**
+ * Parse a pxelinux-style configuration file.
+ * See the following URL for more inforation about the config file syntax:
+ * https://www.syslinux.org/wiki/index.php?title=PXELINUX
+ */
+static int handle_pxelinux_cfg(filename_ip_t *fn_ip, char *cfg, int cfgsize)
+{
+ struct lkia entries[MAX_PXELINUX_ENTRIES];
+ int num_entries = 0;
+ char *ptr = cfg, *eol, *arg;
+ char *defaultlabel = NULL;
+ int def_ent = 0;
+
+ while (ptr < cfg + cfgsize && num_entries < MAX_PXELINUX_ENTRIES) {
+ eol = strchr(ptr, '\n');
+ if (!eol) {
+ eol = cfg + cfgsize;
+ }
+ if (eol > ptr && *(eol - 1) == '\r') {
+ *(eol - 1) = 0;
+ }
+ *eol = '\0';
+ while (*ptr == ' ' || *ptr == '\t') {
+ ptr++;
+ }
+ if (*ptr == 0 || *ptr == '#') { /* Ignore comments and empty lines */
+ goto nextline;
+ }
+ arg = strchr(ptr, ' '); /* Look for space between command and arg */
+ if (!arg) {
+ arg = strchr(ptr, '\t');
+ }
+ if (!arg) {
+ printf("Failed to parse the following line:\n %s\n", ptr);
+ goto nextline;
+ }
+ *arg++ = 0;
+ while (*arg == ' ' || *arg == '\t') {
+ arg++;
+ }
+ if (!strcasecmp("default", ptr)) {
+ defaultlabel = arg;
+ } else if (!strcasecmp("label", ptr)) {
+ entries[num_entries].label = arg;
+ if (defaultlabel && !strcmp(arg, defaultlabel)) {
+ def_ent = num_entries;
+ }
+ num_entries++;
+ } else if (!strcasecmp("kernel", ptr)) {
+ entries[num_entries - 1].kernel = arg;
+ } else if (!strcasecmp("initrd", ptr)) {
+ entries[num_entries - 1].initrd = arg;
+ } else if (!strcasecmp("append", ptr)) {
+ entries[num_entries - 1].append = arg;
+ } else {
+ printf("Command '%s' is not supported.\n", ptr);
+ }
+nextline:
+ ptr = eol + 1;
+ }
+
+ return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
+}
+
+static int net_try_pxelinux_cfgs(filename_ip_t *fn_ip)
+{
+ int rc, idx;
+
+ cfgbuf[sizeof(cfgbuf) - 1] = 0; /* Make sure that it is NUL-terminated */
+
+ printf("Trying pxelinux.cfg files...\n");
+
+ /* Look for config file with MAC address in its name */
+ sprintf((char *)fn_ip->filename,
+ "pxelinux.cfg/%02x-%02x-%02x-%02x-%02x-%02x",
+ mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+ rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
+ if (rc > 0) {
+ return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
+ }
+
+ /* Look for config file with IP address in its name */
+ if (ip_version == 4) {
+ for (idx = 0; idx <= 7; idx++) {
+ sprintf((char *)fn_ip->filename,
+ "pxelinux.cfg/%02X%02X%02X%02X",
+ (fn_ip->own_ip >> 24) & 0xff, (fn_ip->own_ip >> 16) & 0xff,
+ (fn_ip->own_ip >> 8) & 0xff, fn_ip->own_ip & 0xff);
+ fn_ip->filename[strlen((char *)fn_ip->filename) - idx] = 0;
+ rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
+ if (rc > 0) {
+ return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
+ }
+ }
+ }
+
+ /* Try "default" config file */
+ strcpy((char *)fn_ip->filename, "pxelinux.cfg/default");
+ rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
+ if (rc > 0) {
+ return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
+ }
+
+ return -1;
+}
+
+static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
+{
+ int rc;
+ void *baseaddr = (void *)0x2000; /* Load right after the low-core */
+
+ rc = tftp_load(fn_ip, baseaddr, KERNEL_MAX_SIZE - (long)baseaddr);
+
+ if (rc > 0 && rc < sizeof(cfgbuf) - 1) {
+ /* Check whether it is a configuration file instead of a kernel */
+ memcpy(cfgbuf, baseaddr, rc);
+ cfgbuf[rc] = 0; /* Make sure that it is NUL-terminated */
+ if (!strncasecmp("default", cfgbuf, 7) || !strncmp("# ", cfgbuf, 2)) {
+ /* Looks like it is a pxelinux.cfg */
+ return handle_pxelinux_cfg(fn_ip, cfgbuf, rc);
+ }
+ }
+
+ /* Move kernel to right location */
+ memmove(KERNEL_ADDR, baseaddr, rc);
+
+ return rc;
+}
+
void panic(const char *string)
{
sclp_print(string);
@@ -360,7 +548,12 @@ void main(void)
panic("Network initialization failed. Halting.\n");
}
- rc = tftp_load(&fn_ip, NULL, (long)_start);
+ if (strlen((char *)fn_ip.filename) > 0) {
+ rc = net_try_direct_tftp_load(&fn_ip);
+ }
+ if (rc <= 0) {
+ rc = net_try_pxelinux_cfgs(&fn_ip);
+ }
net_uninit(&fn_ip);
--
1.8.3.1
On 18.04.2018 14:31, Thomas Huth wrote:
> Since it is quite cumbersome to manually create a combined kernel with
> initrd image for network booting, we now support loading via pxelinux
> configuration files, too. In these files, the kernel, initrd and command
> line parameters can be specified seperately, and the firmware then takes
> care of glueing everything together in memory after the files have been
> downloaded.
>
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
> pc-bios/s390-ccw/netboot.mak | 5 +-
> pc-bios/s390-ccw/netmain.c | 203 +++++++++++++++++++++++++++++++++++++++++--
> 2 files changed, 201 insertions(+), 7 deletions(-)
>
> diff --git a/pc-bios/s390-ccw/netboot.mak b/pc-bios/s390-ccw/netboot.mak
> index a25d238..8db9573 100644
> --- a/pc-bios/s390-ccw/netboot.mak
> +++ b/pc-bios/s390-ccw/netboot.mak
> @@ -24,8 +24,9 @@ CTYPE_OBJS = isdigit.o isxdigit.o toupper.o
> %.o : $(SLOF_DIR)/lib/libc/ctype/%.c
> $(call quiet-command,$(CC) $(LIBC_CFLAGS) -c -o $@ $<,"CC","$(TARGET_DIR)$@")
>
> -STRING_OBJS = strcat.o strchr.o strcmp.o strcpy.o strlen.o strncmp.o strncpy.o \
> - strstr.o memset.o memcpy.o memmove.o memcmp.o
> +STRING_OBJS = strcasecmp.o strcat.o strchr.o strcmp.o strcpy.o strlen.o \
> + strncasecmp.o strncmp.o strncpy.o strstr.o \
> + memset.o memcpy.o memmove.o memcmp.o
> %.o : $(SLOF_DIR)/lib/libc/string/%.c
> $(call quiet-command,$(CC) $(LIBC_CFLAGS) -c -o $@ $<,"CC","$(TARGET_DIR)$@")
>
> diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
> index e11ed4e..fa62bfe 100644
> --- a/pc-bios/s390-ccw/netmain.c
> +++ b/pc-bios/s390-ccw/netmain.c
> @@ -39,11 +39,17 @@
>
> extern char _start[];
>
> +#define KERNEL_ADDR ((void *)0L)
> +#define KERNEL_MAX_SIZE ((long)_start)
> +#define ARCH_COMMAND_LINE_SIZE 896 /* Taken from Linux kernel */
> +
> char stack[PAGE_SIZE * 8] __attribute__((aligned(PAGE_SIZE)));
> IplParameterBlock iplb __attribute__((aligned(PAGE_SIZE)));
> +static char cfgbuf[2048];
>
> static SubChannelId net_schid = { .one = 1 };
> static int ip_version = 4;
> +static uint8_t mac[6];
> static uint64_t dest_timer;
>
> static uint64_t get_timer_ms(void)
> @@ -136,9 +142,15 @@ static int tftp_load(filename_ip_t *fnip, void *buffer, int len)
> rc = tftp(fnip, buffer, len, DEFAULT_TFTP_RETRIES, &tftp_err, 1, 1428,
> ip_version);
>
> - if (rc > 0) {
> - printf(" TFTP: Received %s (%d KBytes)\n", fnip->filename,
> - rc / 1024);
> + if (rc < 0) {
> + /* Make sure that error messages are put into a new line */
> + printf("\n ");
> + }
> +
> + if (rc > 1024) {
> + printf(" TFTP: Received %s (%d KBytes)\n", fnip->filename, rc / 1024);
> + } else if (rc > 0) {
> + printf(" TFTP: Received %s (%d Bytes)\n", fnip->filename, rc);
> } else if (rc == -1) {
> puts("unknown TFTP error");
> } else if (rc == -2) {
> @@ -201,7 +213,6 @@ static int tftp_load(filename_ip_t *fnip, void *buffer, int len)
>
> static int net_init(filename_ip_t *fn_ip)
> {
> - uint8_t mac[6];
> int rc;
>
> memset(fn_ip, 0, sizeof(filename_ip_t));
> @@ -276,6 +287,183 @@ static void net_uninit(filename_ip_t *fn_ip)
> virtio_net_uninit();
> }
>
> +/* This structure holds the data from one pxelinux.cfg file entry */
> +struct lkia {
> + const char *label;
> + const char *kernel;
> + const char *initrd;
> + const char *append;
> +};
> +
> +static int load_kernel_with_initrd(filename_ip_t *fn_ip, struct lkia *kia)
> +{
> + int rc;
> +
> + printf("Loading pxelinux.cfg entry '%s'\n", kia->label);
> +
> + if (!kia->kernel) {
> + printf("Kernel entry is missing!\n");
> + return -1;
> + }
> +
> + strncpy((char *)&fn_ip->filename, kia->kernel, sizeof(fn_ip->filename));
> + rc = tftp_load(fn_ip, KERNEL_ADDR, KERNEL_MAX_SIZE);
> + if (rc < 0) {
> + return rc;
> + }
> +
> + if (kia->initrd) {
> + uint64_t iaddr = (rc + 0xfff) & ~0xfffUL;
> +
> + strncpy((char *)&fn_ip->filename, kia->initrd, sizeof(fn_ip->filename));
> + rc = tftp_load(fn_ip, (void *)iaddr, KERNEL_MAX_SIZE - iaddr);
> + if (rc < 0) {
> + return rc;
> + }
> + /* Patch location and size: */
> + *(uint64_t *)0x10408 = iaddr;
> + *(uint64_t *)0x10410 = rc;
> + rc += iaddr;
> + }
> +
> + if (kia->append) {
> + strncpy((char *)0x10480, kia->append, ARCH_COMMAND_LINE_SIZE);
> + }
> +
> + return rc;
> +}
> +
> +#define MAX_PXELINUX_ENTRIES 16
> +
> +/**
> + * Parse a pxelinux-style configuration file.
> + * See the following URL for more inforation about the config file syntax:
> + * https://www.syslinux.org/wiki/index.php?title=PXELINUX
> + */
> +static int handle_pxelinux_cfg(filename_ip_t *fn_ip, char *cfg, int cfgsize)
> +{
> + struct lkia entries[MAX_PXELINUX_ENTRIES];
> + int num_entries = 0;
> + char *ptr = cfg, *eol, *arg;
> + char *defaultlabel = NULL;
> + int def_ent = 0;
> +
> + while (ptr < cfg + cfgsize && num_entries < MAX_PXELINUX_ENTRIES) {
> + eol = strchr(ptr, '\n');
> + if (!eol) {
> + eol = cfg + cfgsize;
> + }
> + if (eol > ptr && *(eol - 1) == '\r') {
> + *(eol - 1) = 0;
> + }
> + *eol = '\0';
> + while (*ptr == ' ' || *ptr == '\t') {
> + ptr++;
> + }
> + if (*ptr == 0 || *ptr == '#') { /* Ignore comments and empty lines */
> + goto nextline;
> + }
> + arg = strchr(ptr, ' '); /* Look for space between command and arg */
> + if (!arg) {
> + arg = strchr(ptr, '\t');
> + }
> + if (!arg) {
> + printf("Failed to parse the following line:\n %s\n", ptr);
> + goto nextline;
> + }
> + *arg++ = 0;
> + while (*arg == ' ' || *arg == '\t') {
> + arg++;
> + }
> + if (!strcasecmp("default", ptr)) {
> + defaultlabel = arg;
> + } else if (!strcasecmp("label", ptr)) {
> + entries[num_entries].label = arg;
> + if (defaultlabel && !strcmp(arg, defaultlabel)) {
> + def_ent = num_entries;
> + }
> + num_entries++;
> + } else if (!strcasecmp("kernel", ptr)) {
> + entries[num_entries - 1].kernel = arg;
> + } else if (!strcasecmp("initrd", ptr)) {
> + entries[num_entries - 1].initrd = arg;
> + } else if (!strcasecmp("append", ptr)) {
> + entries[num_entries - 1].append = arg;
> + } else {
> + printf("Command '%s' is not supported.\n", ptr);
> + }
> +nextline:
> + ptr = eol + 1;
> + }
> +
> + return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
> +}
> +
> +static int net_try_pxelinux_cfgs(filename_ip_t *fn_ip)
> +{
> + int rc, idx;
> +
> + cfgbuf[sizeof(cfgbuf) - 1] = 0; /* Make sure that it is NUL-terminated */
> +
> + printf("Trying pxelinux.cfg files...\n");
> +
> + /* Look for config file with MAC address in its name */
> + sprintf((char *)fn_ip->filename,
> + "pxelinux.cfg/%02x-%02x-%02x-%02x-%02x-%02x",
> + mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
> + rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
> + if (rc > 0) {
> + return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
> + }
> +
> + /* Look for config file with IP address in its name */
> + if (ip_version == 4) {
> + for (idx = 0; idx <= 7; idx++) {
> + sprintf((char *)fn_ip->filename,
> + "pxelinux.cfg/%02X%02X%02X%02X",
> + (fn_ip->own_ip >> 24) & 0xff, (fn_ip->own_ip >> 16) & 0xff,
> + (fn_ip->own_ip >> 8) & 0xff, fn_ip->own_ip & 0xff);
> + fn_ip->filename[strlen((char *)fn_ip->filename) - idx] = 0;
> + rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
> + if (rc > 0) {
> + return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
> + }
> + }
> + }
> +
> + /* Try "default" config file */
> + strcpy((char *)fn_ip->filename, "pxelinux.cfg/default");
> + rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
> + if (rc > 0) {
> + return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
> + }
> +
> + return -1;
> +}
> +
> +static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
> +{
> + int rc;
> + void *baseaddr = (void *)0x2000; /* Load right after the low-core */
> +
> + rc = tftp_load(fn_ip, baseaddr, KERNEL_MAX_SIZE - (long)baseaddr);
> +
> + if (rc > 0 && rc < sizeof(cfgbuf) - 1) {
> + /* Check whether it is a configuration file instead of a kernel */
That's interesting because treating the bootfile as pxe-ish config is
what DPM does. Which means that with this change the processor
architecture type 0x1f (Basic) will turn into a superset of 0x20
(Extended). I guess this should be documented somewhere(TM) to avoid
confusion.
> + memcpy(cfgbuf, baseaddr, rc);
> + cfgbuf[rc] = 0; /* Make sure that it is NUL-terminated */
> + if (!strncasecmp("default", cfgbuf, 7) || !strncmp("# ", cfgbuf, 2)) {
> + /* Looks like it is a pxelinux.cfg */
> + return handle_pxelinux_cfg(fn_ip, cfgbuf, rc);> + }
> + }
> +
> + /* Move kernel to right location */
> + memmove(KERNEL_ADDR, baseaddr, rc);
Move this into the if block above. If the tftp_load fails with rc < 0
bad things will happen...
> +
> + return rc;
> +}
> +
> void panic(const char *string)
> {
> sclp_print(string);
> @@ -360,7 +548,12 @@ void main(void)
> panic("Network initialization failed. Halting.\n");
> }
>
> - rc = tftp_load(&fn_ip, NULL, (long)_start);
> + if (strlen((char *)fn_ip.filename) > 0) {
> + rc = net_try_direct_tftp_load(&fn_ip);
> + }
> + if (rc <= 0) {
> + rc = net_try_pxelinux_cfgs(&fn_ip);
> + }
>
> net_uninit(&fn_ip);
>
--
Regards,
Viktor Mihajlovski
On 19.04.2018 09:41, Viktor VM Mihajlovski wrote:
> On 18.04.2018 14:31, Thomas Huth wrote:
>> Since it is quite cumbersome to manually create a combined kernel with
>> initrd image for network booting, we now support loading via pxelinux
>> configuration files, too. In these files, the kernel, initrd and command
>> line parameters can be specified seperately, and the firmware then takes
>> care of glueing everything together in memory after the files have been
>> downloaded.
>>
>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>> ---
>> pc-bios/s390-ccw/netboot.mak | 5 +-
>> pc-bios/s390-ccw/netmain.c | 203 +++++++++++++++++++++++++++++++++++++++++--
>> 2 files changed, 201 insertions(+), 7 deletions(-)
>>
>> diff --git a/pc-bios/s390-ccw/netboot.mak b/pc-bios/s390-ccw/netboot.mak
>> index a25d238..8db9573 100644
>> --- a/pc-bios/s390-ccw/netboot.mak
>> +++ b/pc-bios/s390-ccw/netboot.mak
>> @@ -24,8 +24,9 @@ CTYPE_OBJS = isdigit.o isxdigit.o toupper.o
>> %.o : $(SLOF_DIR)/lib/libc/ctype/%.c
>> $(call quiet-command,$(CC) $(LIBC_CFLAGS) -c -o $@ $<,"CC","$(TARGET_DIR)$@")
>>
>> -STRING_OBJS = strcat.o strchr.o strcmp.o strcpy.o strlen.o strncmp.o strncpy.o \
>> - strstr.o memset.o memcpy.o memmove.o memcmp.o
>> +STRING_OBJS = strcasecmp.o strcat.o strchr.o strcmp.o strcpy.o strlen.o \
>> + strncasecmp.o strncmp.o strncpy.o strstr.o \
>> + memset.o memcpy.o memmove.o memcmp.o
>> %.o : $(SLOF_DIR)/lib/libc/string/%.c
>> $(call quiet-command,$(CC) $(LIBC_CFLAGS) -c -o $@ $<,"CC","$(TARGET_DIR)$@")
>>
>> diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
>> index e11ed4e..fa62bfe 100644
>> --- a/pc-bios/s390-ccw/netmain.c
>> +++ b/pc-bios/s390-ccw/netmain.c
>> @@ -39,11 +39,17 @@
>>
>> extern char _start[];
>>
>> +#define KERNEL_ADDR ((void *)0L)
>> +#define KERNEL_MAX_SIZE ((long)_start)
>> +#define ARCH_COMMAND_LINE_SIZE 896 /* Taken from Linux kernel */
>> +
>> char stack[PAGE_SIZE * 8] __attribute__((aligned(PAGE_SIZE)));
>> IplParameterBlock iplb __attribute__((aligned(PAGE_SIZE)));
>> +static char cfgbuf[2048];
>>
>> static SubChannelId net_schid = { .one = 1 };
>> static int ip_version = 4;
>> +static uint8_t mac[6];
>> static uint64_t dest_timer;
>>
>> static uint64_t get_timer_ms(void)
>> @@ -136,9 +142,15 @@ static int tftp_load(filename_ip_t *fnip, void *buffer, int len)
>> rc = tftp(fnip, buffer, len, DEFAULT_TFTP_RETRIES, &tftp_err, 1, 1428,
>> ip_version);
>>
>> - if (rc > 0) {
>> - printf(" TFTP: Received %s (%d KBytes)\n", fnip->filename,
>> - rc / 1024);
>> + if (rc < 0) {
>> + /* Make sure that error messages are put into a new line */
>> + printf("\n ");
>> + }
>> +
>> + if (rc > 1024) {
>> + printf(" TFTP: Received %s (%d KBytes)\n", fnip->filename, rc / 1024);
>> + } else if (rc > 0) {
>> + printf(" TFTP: Received %s (%d Bytes)\n", fnip->filename, rc);
>> } else if (rc == -1) {
>> puts("unknown TFTP error");
>> } else if (rc == -2) {
>> @@ -201,7 +213,6 @@ static int tftp_load(filename_ip_t *fnip, void *buffer, int len)
>>
>> static int net_init(filename_ip_t *fn_ip)
>> {
>> - uint8_t mac[6];
>> int rc;
>>
>> memset(fn_ip, 0, sizeof(filename_ip_t));
>> @@ -276,6 +287,183 @@ static void net_uninit(filename_ip_t *fn_ip)
>> virtio_net_uninit();
>> }
>>
>> +/* This structure holds the data from one pxelinux.cfg file entry */
>> +struct lkia {
>> + const char *label;
>> + const char *kernel;
>> + const char *initrd;
>> + const char *append;
>> +};
>> +
>> +static int load_kernel_with_initrd(filename_ip_t *fn_ip, struct lkia *kia)
>> +{
>> + int rc;
>> +
>> + printf("Loading pxelinux.cfg entry '%s'\n", kia->label);
>> +
>> + if (!kia->kernel) {
>> + printf("Kernel entry is missing!\n");
>> + return -1;
>> + }
>> +
>> + strncpy((char *)&fn_ip->filename, kia->kernel, sizeof(fn_ip->filename));
>> + rc = tftp_load(fn_ip, KERNEL_ADDR, KERNEL_MAX_SIZE);
>> + if (rc < 0) {
>> + return rc;
>> + }
>> +
>> + if (kia->initrd) {
>> + uint64_t iaddr = (rc + 0xfff) & ~0xfffUL;
>> +
>> + strncpy((char *)&fn_ip->filename, kia->initrd, sizeof(fn_ip->filename));
>> + rc = tftp_load(fn_ip, (void *)iaddr, KERNEL_MAX_SIZE - iaddr);
>> + if (rc < 0) {
>> + return rc;
>> + }
>> + /* Patch location and size: */
>> + *(uint64_t *)0x10408 = iaddr;
>> + *(uint64_t *)0x10410 = rc;
>> + rc += iaddr;
>> + }
>> +
>> + if (kia->append) {
>> + strncpy((char *)0x10480, kia->append, ARCH_COMMAND_LINE_SIZE);
>> + }
>> +
>> + return rc;
>> +}
>> +
>> +#define MAX_PXELINUX_ENTRIES 16
>> +
>> +/**
>> + * Parse a pxelinux-style configuration file.
>> + * See the following URL for more inforation about the config file syntax:
>> + * https://www.syslinux.org/wiki/index.php?title=PXELINUX
>> + */
>> +static int handle_pxelinux_cfg(filename_ip_t *fn_ip, char *cfg, int cfgsize)
>> +{
>> + struct lkia entries[MAX_PXELINUX_ENTRIES];
>> + int num_entries = 0;
>> + char *ptr = cfg, *eol, *arg;
>> + char *defaultlabel = NULL;
>> + int def_ent = 0;
>> +
>> + while (ptr < cfg + cfgsize && num_entries < MAX_PXELINUX_ENTRIES) {
>> + eol = strchr(ptr, '\n');
>> + if (!eol) {
>> + eol = cfg + cfgsize;
>> + }
>> + if (eol > ptr && *(eol - 1) == '\r') {
>> + *(eol - 1) = 0;
>> + }
>> + *eol = '\0';
>> + while (*ptr == ' ' || *ptr == '\t') {
>> + ptr++;
>> + }
>> + if (*ptr == 0 || *ptr == '#') { /* Ignore comments and empty lines */
>> + goto nextline;
>> + }
>> + arg = strchr(ptr, ' '); /* Look for space between command and arg */
>> + if (!arg) {
>> + arg = strchr(ptr, '\t');
>> + }
>> + if (!arg) {
>> + printf("Failed to parse the following line:\n %s\n", ptr);
>> + goto nextline;
>> + }
>> + *arg++ = 0;
>> + while (*arg == ' ' || *arg == '\t') {
>> + arg++;
>> + }
>> + if (!strcasecmp("default", ptr)) {
>> + defaultlabel = arg;
>> + } else if (!strcasecmp("label", ptr)) {
>> + entries[num_entries].label = arg;
>> + if (defaultlabel && !strcmp(arg, defaultlabel)) {
>> + def_ent = num_entries;
>> + }
>> + num_entries++;
>> + } else if (!strcasecmp("kernel", ptr)) {
>> + entries[num_entries - 1].kernel = arg;
>> + } else if (!strcasecmp("initrd", ptr)) {
>> + entries[num_entries - 1].initrd = arg;
>> + } else if (!strcasecmp("append", ptr)) {
>> + entries[num_entries - 1].append = arg;
>> + } else {
>> + printf("Command '%s' is not supported.\n", ptr);
>> + }
>> +nextline:
>> + ptr = eol + 1;
>> + }
>> +
>> + return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
>> +}
>> +
>> +static int net_try_pxelinux_cfgs(filename_ip_t *fn_ip)
>> +{
>> + int rc, idx;
>> +
>> + cfgbuf[sizeof(cfgbuf) - 1] = 0; /* Make sure that it is NUL-terminated */
>> +
>> + printf("Trying pxelinux.cfg files...\n");
>> +
>> + /* Look for config file with MAC address in its name */
>> + sprintf((char *)fn_ip->filename,
>> + "pxelinux.cfg/%02x-%02x-%02x-%02x-%02x-%02x",
>> + mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
>> + rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
>> + if (rc > 0) {
>> + return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
>> + }
>> +
>> + /* Look for config file with IP address in its name */
>> + if (ip_version == 4) {
>> + for (idx = 0; idx <= 7; idx++) {
>> + sprintf((char *)fn_ip->filename,
>> + "pxelinux.cfg/%02X%02X%02X%02X",
>> + (fn_ip->own_ip >> 24) & 0xff, (fn_ip->own_ip >> 16) & 0xff,
>> + (fn_ip->own_ip >> 8) & 0xff, fn_ip->own_ip & 0xff);
>> + fn_ip->filename[strlen((char *)fn_ip->filename) - idx] = 0;
>> + rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
>> + if (rc > 0) {
>> + return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
>> + }
>> + }
>> + }
>> +
>> + /* Try "default" config file */
>> + strcpy((char *)fn_ip->filename, "pxelinux.cfg/default");
>> + rc = tftp_load(fn_ip, cfgbuf, sizeof(cfgbuf) - 1);
>> + if (rc > 0) {
>> + return handle_pxelinux_cfg(fn_ip, cfgbuf, sizeof(cfgbuf));
>> + }
>> +
>> + return -1;
>> +}
>> +
>> +static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
>> +{
>> + int rc;
>> + void *baseaddr = (void *)0x2000; /* Load right after the low-core */
>> +
>> + rc = tftp_load(fn_ip, baseaddr, KERNEL_MAX_SIZE - (long)baseaddr);
>> +
>> + if (rc > 0 && rc < sizeof(cfgbuf) - 1) {
>> + /* Check whether it is a configuration file instead of a kernel */
> That's interesting because treating the bootfile as pxe-ish config is
> what DPM does. Which means that with this change the processor
> architecture type 0x1f (Basic) will turn into a superset of 0x20
> (Extended).
Is there any reference available what "basic" and "extended" exactly
mean? I just know that there are these two values registered by you at
the IANA:
https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml#processor-architecture
... but I haven't seen a description of the differences of these two
values yet.
> I guess this should be documented somewhere(TM) to avoid
> confusion.
I plan to update https://wiki.qemu.org/Features/S390xNetworkBoot once
the patches have been merged upstream.
>> + memcpy(cfgbuf, baseaddr, rc);
>> + cfgbuf[rc] = 0; /* Make sure that it is NUL-terminated */
>> + if (!strncasecmp("default", cfgbuf, 7) || !strncmp("# ", cfgbuf, 2)) {
>> + /* Looks like it is a pxelinux.cfg */
>> + return handle_pxelinux_cfg(fn_ip, cfgbuf, rc);> + }
>> + }
>> +
>> + /* Move kernel to right location */
>> + memmove(KERNEL_ADDR, baseaddr, rc);
> Move this into the if block above. If the tftp_load fails with rc < 0
> bad things will happen...
Oops, good catch, this should of course only be done if rc > 0 ... will
fix it in v2.
Thomas
On 19.04.2018 10:17, Thomas Huth wrote:
> On 19.04.2018 09:41, Viktor VM Mihajlovski wrote:
>> On 18.04.2018 14:31, Thomas Huth wrote:
>>> Since it is quite cumbersome to manually create a combined kernel with
>>> initrd image for network booting, we now support loading via pxelinux
>>> configuration files, too. In these files, the kernel, initrd and command
>>> line parameters can be specified seperately, and the firmware then takes
>>> care of glueing everything together in memory after the files have been
>>> downloaded.
[...]
>>> +static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
>>> +{
>>> + int rc;
>>> + void *baseaddr = (void *)0x2000; /* Load right after the low-core */
>>> +
>>> + rc = tftp_load(fn_ip, baseaddr, KERNEL_MAX_SIZE - (long)baseaddr);
>>> +
>>> + if (rc > 0 && rc < sizeof(cfgbuf) - 1) {
>>> + /* Check whether it is a configuration file instead of a kernel */
>> That's interesting because treating the bootfile as pxe-ish config is
>> what DPM does. Which means that with this change the processor
>> architecture type 0x1f (Basic) will turn into a superset of 0x20
>> (Extended).
>
> Is there any reference available what "basic" and "extended" exactly
> mean? I just know that there are these two values registered by you at
> the IANA:
>
> https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml#processor-architecture
>
> ... but I haven't seen a description of the differences of these two
> values yet.
>
Yep, the IANA stuff is pretty terse for all architectures. In a
nutshell: 0x1f is standard DHCP-based boot (bootfile is a single
executable binary) and 0x20 serves a pxe-style config file instead.
In fact, "processor architecture identifier" is a misnomer, as it
describes a pair of processor architecture and firmware.
Since the QEMU firmware has two significant extensions now (insfile and
direct config file loading), it might be worthwhile to add a new
identifier value (say s390 QEMU PC-BIOS or similar) announcing the new
capabilities, so that a boot server admin can setup her system accordingly.
>> I guess this should be documented somewhere(TM) to avoid
>> confusion.
>
> I plan to update https://wiki.qemu.org/Features/S390xNetworkBoot once
> the patches have been merged upstream.
>
sounds good.
[...]
--
Regards,
Viktor Mihajlovski
On 19.04.2018 14:40, Viktor VM Mihajlovski wrote:
> On 19.04.2018 10:17, Thomas Huth wrote:
>> On 19.04.2018 09:41, Viktor VM Mihajlovski wrote:
>>> On 18.04.2018 14:31, Thomas Huth wrote:
>>>> Since it is quite cumbersome to manually create a combined kernel with
>>>> initrd image for network booting, we now support loading via pxelinux
>>>> configuration files, too. In these files, the kernel, initrd and command
>>>> line parameters can be specified seperately, and the firmware then takes
>>>> care of glueing everything together in memory after the files have been
>>>> downloaded.
> [...]
>>>> +static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
>>>> +{
>>>> + int rc;
>>>> + void *baseaddr = (void *)0x2000; /* Load right after the low-core */
>>>> +
>>>> + rc = tftp_load(fn_ip, baseaddr, KERNEL_MAX_SIZE - (long)baseaddr);
>>>> +
>>>> + if (rc > 0 && rc < sizeof(cfgbuf) - 1) {
>>>> + /* Check whether it is a configuration file instead of a kernel */
>>> That's interesting because treating the bootfile as pxe-ish config is
>>> what DPM does. Which means that with this change the processor
>>> architecture type 0x1f (Basic) will turn into a superset of 0x20
>>> (Extended).
>>
>> Is there any reference available what "basic" and "extended" exactly
>> mean? I just know that there are these two values registered by you at
>> the IANA:
>>
>> https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml#processor-architecture
>>
>> ... but I haven't seen a description of the differences of these two
>> values yet.
>>
> Yep, the IANA stuff is pretty terse for all architectures. In a
> nutshell: 0x1f is standard DHCP-based boot (bootfile is a single
> executable binary) and 0x20 serves a pxe-style config file instead.
Can 0x20 also still handle binary files, or only pxe-style config files?
> In fact, "processor architecture identifier" is a misnomer, as it
> describes a pair of processor architecture and firmware.
Yeah, I know ... it's even worse nowadays, it's processor + firmware +
TCP/IP protocol (HTTP vs. TFTP) ... we should have properly untangled
that when doing RFC 5970, but it was already hard enough to get that
accepted in the current shape, so we missed to clean up the mess from
RFC 4578 / PXE :-(
> Since the QEMU firmware has two significant extensions now (insfile and
> direct config file loading), it might be worthwhile to add a new
> identifier value (say s390 QEMU PC-BIOS or similar) announcing the new
> capabilities, so that a boot server admin can setup her system accordingly.
Not sure ... too many processory-architecture-type entries might also
rather be too confusing for the users? ... so if 0x20 can also handle
binary files like 0x1f, I'd maybe simply go with 0x20 and mainly promote
pxelinux config files in the documentation?
Thomas
On 19.04.2018 18:55, Thomas Huth wrote:
> On 19.04.2018 14:40, Viktor VM Mihajlovski wrote:
>> On 19.04.2018 10:17, Thomas Huth wrote:
>>> On 19.04.2018 09:41, Viktor VM Mihajlovski wrote:
>>>> On 18.04.2018 14:31, Thomas Huth wrote:
>>>>> Since it is quite cumbersome to manually create a combined kernel with
>>>>> initrd image for network booting, we now support loading via pxelinux
>>>>> configuration files, too. In these files, the kernel, initrd and command
>>>>> line parameters can be specified seperately, and the firmware then takes
>>>>> care of glueing everything together in memory after the files have been
>>>>> downloaded.
>> [...]
>>>>> +static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
>>>>> +{
>>>>> + int rc;
>>>>> + void *baseaddr = (void *)0x2000; /* Load right after the low-core */
>>>>> +
>>>>> + rc = tftp_load(fn_ip, baseaddr, KERNEL_MAX_SIZE - (long)baseaddr);
>>>>> +
>>>>> + if (rc > 0 && rc < sizeof(cfgbuf) - 1) {
>>>>> + /* Check whether it is a configuration file instead of a kernel */
>>>> That's interesting because treating the bootfile as pxe-ish config is
>>>> what DPM does. Which means that with this change the processor
>>>> architecture type 0x1f (Basic) will turn into a superset of 0x20
>>>> (Extended).
>>>
>>> Is there any reference available what "basic" and "extended" exactly
>>> mean? I just know that there are these two values registered by you at
>>> the IANA:
>>>
>>> https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml#processor-architecture
>>>
>>> ... but I haven't seen a description of the differences of these two
>>> values yet.
>>>
>> Yep, the IANA stuff is pretty terse for all architectures. In a
>> nutshell: 0x1f is standard DHCP-based boot (bootfile is a single
>> executable binary) and 0x20 serves a pxe-style config file instead.
>
> Can 0x20 also still handle binary files, or only pxe-style config files?
>
Unfortunately, DPM has no support for binaries which was the reason we
ended up with two different identifiers
>> In fact, "processor architecture identifier" is a misnomer, as it
>> describes a pair of processor architecture and firmware.
>
> Yeah, I know ... it's even worse nowadays, it's processor + firmware +
> TCP/IP protocol (HTTP vs. TFTP) ... we should have properly untangled
> that when doing RFC 5970, but it was already hard enough to get that
> accepted in the current shape, so we missed to clean up the mess from
> RFC 4578 / PXE :-(
>
>> Since the QEMU firmware has two significant extensions now (insfile and
>> direct config file loading), it might be worthwhile to add a new
>> identifier value (say s390 QEMU PC-BIOS or similar) announcing the new
>> capabilities, so that a boot server admin can setup her system accordingly.
>
> Not sure ... too many processory-architecture-type entries might also
> rather be too confusing for the users? ... so if 0x20 can also handle
> binary files like 0x1f, I'd maybe simply go with 0x20 and mainly promote
> pxelinux config files in the documentation?
>
Well, if we don't add another identifier, and I feel reluctant about it
as well for the reasons you wrote, we may stick with 0x1f and consider
the additional capabilities as being optional (for special needs only).
Remember that a client-specific pxe-style config or insfile have to be
tied to a client identifier that can be referenced in the DHCP server
configuration (usually the MAC address). I.e., if MAC equals so-and-so
send back bootfile name xyz.
But this is exactly what the pxelinux config file probing offers: having
client (or client-group) specific configs without the need to
reconfigure the DHCP server for every new (virtual) machine. My
assumption is that server admins will go with the pxelinux config
approach they're used from other architectures (which becomes now even
easier with your changes).
> Thomas
>
--
Regards,
Viktor Mihajlovski
On 20.04.2018 08:53, Viktor VM Mihajlovski wrote: > On 19.04.2018 18:55, Thomas Huth wrote: >> On 19.04.2018 14:40, Viktor VM Mihajlovski wrote: [...] >>>>> That's interesting because treating the bootfile as pxe-ish config is >>>>> what DPM does. Which means that with this change the processor >>>>> architecture type 0x1f (Basic) will turn into a superset of 0x20 >>>>> (Extended). >>>> >>>> Is there any reference available what "basic" and "extended" exactly >>>> mean? I just know that there are these two values registered by you at >>>> the IANA: >>>> >>>> https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml#processor-architecture >>>> >>>> ... but I haven't seen a description of the differences of these two >>>> values yet. >>>> >>> Yep, the IANA stuff is pretty terse for all architectures. In a >>> nutshell: 0x1f is standard DHCP-based boot (bootfile is a single >>> executable binary) and 0x20 serves a pxe-style config file instead. >> >> Can 0x20 also still handle binary files, or only pxe-style config files? >> > Unfortunately, DPM has no support for binaries which was the reason we > ended up with two different identifiers Ok, so switching to 0x20 is not an option for us here. >>> In fact, "processor architecture identifier" is a misnomer, as it >>> describes a pair of processor architecture and firmware. >> >> Yeah, I know ... it's even worse nowadays, it's processor + firmware + >> TCP/IP protocol (HTTP vs. TFTP) ... we should have properly untangled >> that when doing RFC 5970, but it was already hard enough to get that >> accepted in the current shape, so we missed to clean up the mess from >> RFC 4578 / PXE :-( >> >>> Since the QEMU firmware has two significant extensions now (insfile and >>> direct config file loading), it might be worthwhile to add a new >>> identifier value (say s390 QEMU PC-BIOS or similar) announcing the new >>> capabilities, so that a boot server admin can setup her system accordingly. >> >> Not sure ... too many processory-architecture-type entries might also >> rather be too confusing for the users? ... so if 0x20 can also handle >> binary files like 0x1f, I'd maybe simply go with 0x20 and mainly promote >> pxelinux config files in the documentation? >> > Well, if we don't add another identifier, and I feel reluctant about it > as well for the reasons you wrote, we may stick with 0x1f and consider > the additional capabilities as being optional (for special needs only). I tend to stay with 0x1f, since booting binaries is still the "primary" interface (the first check for the "default" or "# " magic keywords is not 100% reliable, since the config file could also start with another command, and the probing of pxelinux.cfg/* files is only tried afterwards). Thomas
On 20.04.2018 09:36, Thomas Huth wrote: > On 20.04.2018 08:53, Viktor VM Mihajlovski wrote: >> On 19.04.2018 18:55, Thomas Huth wrote: [...] >> Well, if we don't add another identifier, and I feel reluctant about it >> as well for the reasons you wrote, we may stick with 0x1f and consider >> the additional capabilities as being optional (for special needs only). > > I tend to stay with 0x1f, since booting binaries is still the "primary" > interface (the first check for the "default" or "# " magic keywords is > not 100% reliable, since the config file could also start with another > command, and the probing of pxelinux.cfg/* files is only tried afterwards). > Good. It would be important though to define and document the best way to configure a pxelinux setup: empty bootfile name, bootfile empty (or not existent) or a special file format for the bootfile content (like 'PXE0' in EBCDIC). The former two carry the danger of accidentally enabling the pxe-style boot process. > Thomas > -- Regards, Viktor Mihajlovski
On 20.04.2018 09:54, Viktor VM Mihajlovski wrote:
> On 20.04.2018 09:36, Thomas Huth wrote:
>> On 20.04.2018 08:53, Viktor VM Mihajlovski wrote:
>>> On 19.04.2018 18:55, Thomas Huth wrote:
> [...]
>>> Well, if we don't add another identifier, and I feel reluctant about it
>>> as well for the reasons you wrote, we may stick with 0x1f and consider
>>> the additional capabilities as being optional (for special needs only).
>>
>> I tend to stay with 0x1f, since booting binaries is still the "primary"
>> interface (the first check for the "default" or "# " magic keywords is
>> not 100% reliable, since the config file could also start with another
>> command, and the probing of pxelinux.cfg/* files is only tried afterwards).
>>
> Good. It would be important though to define and document the best way
> to configure a pxelinux setup: empty bootfile name, bootfile empty (or
> not existent) or a special file format for the bootfile content (like
> 'PXE0' in EBCDIC). The former two carry the danger of accidentally
> enabling the pxe-style boot process.
I don't like the idea of providing a bootfile with a magic content ...
if you have to provide a bootfile, you could also go with specifying
pxelinux.cfg/default (or whatever) directly, you just have to make sure
that the file starts with the right magic ("default" or "# ").
But I agree that starting to guess the non-MAC-based filenames in case
the boot file name is empty carries some danger, indeed. If we load
pxelinux.cfg/default on s390x, who guarantees that this was not the
default file for x86 instead? Maybe we should rather use "pzelinux.cfg"
as directory ;-) ?
Or maybe it would rather make sense to force the users to specify the
path to the pxelinux config files instead, ending with a slash, so they
have to put "pxelinux.cfg/" or whatever location into the bootfile
parameter?
Thomas
On 20.04.2018 10:40, Thomas Huth wrote:
> On 20.04.2018 09:54, Viktor VM Mihajlovski wrote:
>> On 20.04.2018 09:36, Thomas Huth wrote:
>>> On 20.04.2018 08:53, Viktor VM Mihajlovski wrote:
>>>> On 19.04.2018 18:55, Thomas Huth wrote:
>> [...]
>>>> Well, if we don't add another identifier, and I feel reluctant about it
>>>> as well for the reasons you wrote, we may stick with 0x1f and consider
>>>> the additional capabilities as being optional (for special needs only).
>>>
>>> I tend to stay with 0x1f, since booting binaries is still the "primary"
>>> interface (the first check for the "default" or "# " magic keywords is
>>> not 100% reliable, since the config file could also start with another
>>> command, and the probing of pxelinux.cfg/* files is only tried afterwards).
>>>
>> Good. It would be important though to define and document the best way
>> to configure a pxelinux setup: empty bootfile name, bootfile empty (or
>> not existent) or a special file format for the bootfile content (like
>> 'PXE0' in EBCDIC). The former two carry the danger of accidentally
>> enabling the pxe-style boot process.
>
> I don't like the idea of providing a bootfile with a magic content ...
> if you have to provide a bootfile, you could also go with specifying
> pxelinux.cfg/default (or whatever) directly, you just have to make sure
> that the file starts with the right magic ("default" or "# ").
>
> But I agree that starting to guess the non-MAC-based filenames in case
> the boot file name is empty carries some danger, indeed. If we load
> pxelinux.cfg/default on s390x, who guarantees that this was not the
> default file for x86 instead? Maybe we should rather use "pzelinux.cfg"
> as directory ;-) ?
Yep. Sounds as if a null bootfile name should not be allowed at all and
should be rejected by the netboot bios.
>
> Or maybe it would rather make sense to force the users to specify the
> path to the pxelinux config files instead, ending with a slash, so they
> have to put "pxelinux.cfg/" or whatever location into the bootfile
> parameter?
Since the bootfile has to be architecture specific anyway, it would a
good idea to put it into a separate directory, e.g. "/tftpboot/s390".
If the bootfile reported would be "/s390/" or a (nonexisting)
"/s390/pxelinux.0", the new pxe loader could start its
pxelinux.cfg/whatever probing from there. "/" or
"/some-not-existing-file" would be a special case thereof.
>
> Thomas
>
--
Regards,
Viktor Mihajlovski
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