On 10/24/23 02:21, seanedm...@linux.microsoft.com wrote:
From: Sean Edmond <seanedm...@microsoft.com>
Allow dhcp server pass pxe config file full path by using option 209
Signed-off-by: Sean Edmond <seanedm...@microsoft.com>
---
cmd/Kconfig | 4 ++++
cmd/pxe.c | 10 ++++++++++
net/bootp.c | 21 +++++++++++++++++++++
3 files changed, 35 insertions(+)
diff --git a/cmd/Kconfig b/cmd/Kconfig
index 5bc0a92d57..adbb1a6187 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1826,6 +1826,10 @@ config BOOTP_PXE_CLIENTARCH
default 0x15 if ARM
default 0x0 if X86
+config BOOTP_PXE_DHCP_OPTION
+ bool "Request & store 'pxe_configfile' from BOOTP/DHCP server"
+ depends on BOOTP_PXE
Why should this be disabled by default?
Do we really want a separate config variable?
+
config BOOTP_VCI_STRING
string
depends on CMD_BOOTP
diff --git a/cmd/pxe.c b/cmd/pxe.c
index 704589702f..9404f44518 100644
--- a/cmd/pxe.c
+++ b/cmd/pxe.c
@@ -65,6 +65,8 @@ static int pxe_dhcp_option_path(struct pxe_context *ctx,
unsigned long pxefile_a
int ret = get_pxe_file(ctx, pxelinux_configfile, pxefile_addr_r);
free(pxelinux_configfile);
+ /* set to NULL to avoid double-free if DHCP is tried again */
+ pxelinux_configfile = NULL;
return ret;
}
@@ -141,6 +143,14 @@ int pxe_get(ulong pxefile_addr_r, char **bootdirp, ulong
*sizep, bool use_ipv6)
env_get("bootfile"), use_ipv6))
return -ENOMEM;
+ if (IS_ENABLED(CONFIG_BOOTP_PXE_DHCP_OPTION) &&
+ pxelinux_configfile && !use_ipv6) {
+ if (pxe_dhcp_option_path(&ctx, pxefile_addr_r) > 0)
+ goto done;
+
+ goto error_exit;
+ }
+
if (IS_ENABLED(CONFIG_DHCP6_PXE_DHCP_OPTION) &&
pxelinux_configfile && use_ipv6) {
if (pxe_dhcp_option_path(&ctx, pxefile_addr_r) > 0)
diff --git a/net/bootp.c b/net/bootp.c
index 7b0f45e18a..6800290963 100644
--- a/net/bootp.c
+++ b/net/bootp.c
@@ -26,6 +26,7 @@
#ifdef CONFIG_BOOTP_RANDOM_DELAY
#include "net_rand.h"
#endif
+#include <malloc.h>
#define BOOTP_VENDOR_MAGIC 0x63825363 /* RFC1048 Magic Cookie */
@@ -601,6 +602,10 @@ static int dhcp_extended(u8 *e, int message_type, struct
in_addr server_ip,
*e++ = 42;
*cnt += 1;
#endif
+ if (IS_ENABLED(CONFIG_BOOTP_PXE_DHCP_OPTION)) {
+ *e++ = 209; /* PXELINUX Config File */
+ *cnt += 1;
+ }
/* no options, so back up to avoid sending an empty request list */
if (*cnt == 0)
e -= 2;
@@ -909,6 +914,22 @@ static void dhcp_process_options(uchar *popt, uchar *end)
net_boot_file_name[size] = 0;
}
break;
+ case 209: /* PXELINUX Config File */
This 209 appears in multiple places. Please, define a constant, e.g.
DHCP_OPTION_CONFIG_FILE, in bootp.h and use the symbolic name. Please,
document the constant referring to RFC 5071.
+ if (IS_ENABLED(CONFIG_BOOTP_PXE_DHCP_OPTION)) {
+ /* In case it has already been allocated when
get DHCP Offer packet,
+ * free first to avoid memory leak.
+ */
+ if (pxelinux_configfile)
+ free(pxelinux_configfile);
+
+ pxelinux_configfile = (char *)malloc((oplen +
1) * sizeof(char));
+
+ if (pxelinux_configfile)
+ strlcpy(pxelinux_configfile, popt + 2,
oplen + 1);
+ else
+ printf("Error: Failed to allocate
pxelinux_configfile\n");
We do the same in dhcp6_parse_options(). Please, factor out a common
function to avoid code duplication.
Best regards
Heinrich
+ }
+ break;
default:
#if defined(CONFIG_BOOTP_VENDOREX)
if (dhcp_vendorex_proc(popt))
