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Diffstat (limited to 'netboot.c')
-rw-r--r--netboot.c221
1 files changed, 103 insertions, 118 deletions
diff --git a/netboot.c b/netboot.c
index a83c82ae..ad5d37e9 100644
--- a/netboot.c
+++ b/netboot.c
@@ -38,16 +38,9 @@
#include <string.h>
#include "shim.h"
#include "netboot.h"
+#include "str.h"
-static inline unsigned short int __swap16(unsigned short int x)
-{
- __asm__("xchgb %b0,%h0"
- : "=q" (x)
- : "0" (x));
- return x;
-}
-
-#define ntohs(x) __swap16(x)
+#define ntohs(x) __builtin_bswap16(x) /* supported both by GCC and clang */
#define htons(x) ntohs(x)
static EFI_PXE_BASE_CODE *pxe;
@@ -84,105 +77,65 @@ translate_slashes(char *str)
* Returns TRUE if we identify a protocol that is enabled and Providing us with
* the needed information to fetch a grubx64.efi image
*/
-BOOLEAN findNetboot(EFI_HANDLE image_handle)
+BOOLEAN findNetboot(EFI_HANDLE device)
{
- UINTN bs = sizeof(EFI_HANDLE);
- EFI_GUID pxe_base_code_protocol = EFI_PXE_BASE_CODE_PROTOCOL;
- EFI_HANDLE *hbuf;
- BOOLEAN rc = FALSE;
- void *buffer = AllocatePool(bs);
- UINTN errcnt = 0;
- UINTN i;
EFI_STATUS status;
- if (!buffer)
+ status = uefi_call_wrapper(BS->HandleProtocol, 3, device,
+ &PxeBaseCodeProtocol, (VOID **)&pxe);
+ if (status != EFI_SUCCESS) {
+ pxe = NULL;
return FALSE;
-
-try_again:
- status = uefi_call_wrapper(BS->LocateHandle,5, ByProtocol,
- &pxe_base_code_protocol, NULL, &bs,
- buffer);
-
- if (status == EFI_BUFFER_TOO_SMALL) {
- errcnt++;
- FreePool(buffer);
- if (errcnt > 1)
- return FALSE;
- buffer = AllocatePool(bs);
- if (!buffer)
- return FALSE;
- goto try_again;
}
- if (status == EFI_NOT_FOUND) {
- FreePool(buffer);
+ if (!pxe || !pxe->Mode) {
+ pxe = NULL;
return FALSE;
}
- /*
- * We have a list of pxe supporting protocols, lets see if any are
- * active
- */
- hbuf = buffer;
- pxe = NULL;
- for (i=0; i < (bs / sizeof(EFI_HANDLE)); i++) {
- status = uefi_call_wrapper(BS->OpenProtocol, 6, hbuf[i],
- &pxe_base_code_protocol,
- (void **)&pxe, image_handle, NULL,
- EFI_OPEN_PROTOCOL_GET_PROTOCOL);
-
- if (status != EFI_SUCCESS) {
- pxe = NULL;
- continue;
- }
-
- if (!pxe || !pxe->Mode) {
- pxe = NULL;
- continue;
- }
-
- if (pxe->Mode->Started && pxe->Mode->DhcpAckReceived) {
- /*
- * We've located a pxe protocol handle thats been
- * started and has received an ACK, meaning its
- * something we'll be able to get tftp server info
- * out of
- */
- rc = TRUE;
- break;
- }
-
+ if (!pxe->Mode->Started || !pxe->Mode->DhcpAckReceived) {
+ pxe = NULL;
+ return FALSE;
}
- FreePool(buffer);
- return rc;
+ /*
+ * We've located a pxe protocol handle thats been started and has
+ * received an ACK, meaning its something we'll be able to get
+ * tftp server info out of
+ */
+ return TRUE;
}
static CHAR8 *get_v6_bootfile_url(EFI_PXE_BASE_CODE_DHCPV6_PACKET *pkt)
{
- void *optr;
- EFI_DHCP6_PACKET_OPTION *option;
- CHAR8 *url;
- UINT32 urllen;
+ void *optr = NULL, *end = NULL;
+ EFI_DHCP6_PACKET_OPTION *option = NULL;
+ CHAR8 *url = NULL;
+ UINT32 urllen = 0;
optr = pkt->DhcpOptions;
+ end = optr + sizeof(pkt->DhcpOptions);
- for(;;) {
+ for (;;) {
option = (EFI_DHCP6_PACKET_OPTION *)optr;
if (ntohs(option->OpCode) == 0)
- return NULL;
+ break;
if (ntohs(option->OpCode) == 59) {
/* This is the bootfile url option */
urllen = ntohs(option->Length);
- url = AllocateZeroPool(urllen+1);
+ if ((void *)(option->Data + urllen) > end)
+ break;
+ url = AllocateZeroPool(urllen + 1);
if (!url)
- return NULL;
+ break;
memcpy(url, option->Data, urllen);
return url;
}
optr += 4 + ntohs(option->Length);
+ if (optr + sizeof(EFI_DHCP6_PACKET_OPTION) > end)
+ break;
}
return NULL;
@@ -208,45 +161,60 @@ static CHAR16 str2ns(CHAR8 *str)
static CHAR8 *str2ip6(CHAR8 *str)
{
- UINT8 i, j, p;
- size_t len;
- CHAR8 *a, *b, t;
- static UINT16 ip[8];
+ UINT8 i = 0, j = 0, p = 0;
+ size_t len = 0, dotcount = 0;
+ enum { MAX_IP6_DOTS = 7 };
+ CHAR8 *a = NULL, *b = NULL, t = 0;
+ static UINT16 ip[8];
- for(i=0; i < 8; i++) {
- ip[i] = 0;
- }
- len = strlen(str);
- a = b = str;
- for(i=p=0; i < len; i++, b++) {
- if (*b != ':')
- continue;
- *b = '\0';
- ip[p++] = str2ns(a);
- *b = ':';
- a = b + 1;
- if ( *(b+1) == ':' )
- break;
- }
- a = b = (str + len);
- for(j=len, p=7; j > i; j--, a--) {
- if (*a != ':')
- continue;
- t = *b;
- *b = '\0';
- ip[p--] = str2ns(a+1);
- *b = t;
- b = a;
- }
- return (CHAR8 *)ip;
+ memset(ip, 0, sizeof(ip));
+
+ /* Count amount of ':' to prevent overflows.
+ * max. count = 7. Returns an invalid ip6 that
+ * can be checked against
+ */
+ for (a = str; *a != 0; ++a) {
+ if (*a == ':')
+ ++dotcount;
+ }
+ if (dotcount > MAX_IP6_DOTS)
+ return (CHAR8 *)ip;
+
+ len = strlen(str);
+ a = b = str;
+ for (i = p = 0; i < len; i++, b++) {
+ if (*b != ':')
+ continue;
+ *b = '\0';
+ ip[p++] = str2ns(a);
+ *b = ':';
+ a = b + 1;
+ if (b[1] == ':' )
+ break;
+ }
+ a = b = (str + len);
+ for (j = len, p = 7; j > i; j--, a--) {
+ if (*a != ':')
+ continue;
+ t = *b;
+ *b = '\0';
+ ip[p--] = str2ns(a+1);
+ *b = t;
+ b = a;
+ }
+ return (CHAR8 *)ip;
}
static BOOLEAN extract_tftp_info(CHAR8 *url)
{
CHAR8 *start, *end;
CHAR8 ip6str[40];
+ CHAR8 ip6inv[16];
CHAR8 *template = (CHAR8 *)translate_slashes(DEFAULT_LOADER_CHAR);
+ // to check against str2ip6() errors
+ memset(ip6inv, 0, sizeof(ip6inv));
+
if (strncmp((UINT8 *)url, (UINT8 *)"tftp://", 7)) {
Print(L"URLS MUST START WITH tftp://\n");
return FALSE;
@@ -261,19 +229,21 @@ static BOOLEAN extract_tftp_info(CHAR8 *url)
end = start;
while ((*end != '\0') && (*end != ']')) {
end++;
- if (end - start > 39) {
+ if (end - start >= (int)sizeof(ip6str)) {
Print(L"TFTP URL includes malformed IPv6 address\n");
return FALSE;
}
}
- if (end == '\0') {
+ if (*end == '\0') {
Print(L"TFTP SERVER MUST BE ENCLOSED IN [..]\n");
return FALSE;
}
- memset(ip6str, 0, 40);
+ memset(ip6str, 0, sizeof(ip6str));
memcpy(ip6str, start, end - start);
end++;
memcpy(&tftp_addr.v6, str2ip6(ip6str), 16);
+ if (memcmp(&tftp_addr.v6, ip6inv, sizeof(ip6inv)) == 0)
+ return FALSE;
full_path = AllocateZeroPool(strlen(end)+strlen(template)+1);
if (!full_path)
return FALSE;
@@ -305,19 +275,34 @@ static EFI_STATUS parseDhcp6()
static EFI_STATUS parseDhcp4()
{
- CHAR8 *template = (CHAR8 *)DEFAULT_LOADER_CHAR;
- full_path = AllocateZeroPool(strlen(template)+1);
+ CHAR8 *template = (CHAR8 *)translate_slashes(DEFAULT_LOADER_CHAR);
+ INTN template_len = strlen(template) + 1;
+
+ INTN dir_len = strnlena(pxe->Mode->DhcpAck.Dhcpv4.BootpBootFile, 127);
+ INTN i;
+ UINT8 *dir = pxe->Mode->DhcpAck.Dhcpv4.BootpBootFile;
+
+ for (i = dir_len; i >= 0; i--) {
+ if (dir[i] == '/')
+ break;
+ }
+ dir_len = (i >= 0) ? i + 1 : 0;
+
+ full_path = AllocateZeroPool(dir_len + template_len);
if (!full_path)
return EFI_OUT_OF_RESOURCES;
+ if (dir_len > 0) {
+ strncpya(full_path, dir, dir_len);
+ if (full_path[dir_len-1] == '/' && template[0] == '/')
+ full_path[dir_len-1] = '\0';
+ }
+ if (dir_len == 0 && dir[0] != '/' && template[0] == '/')
+ template++;
+ strcata(full_path, template);
memcpy(&tftp_addr.v4, pxe->Mode->DhcpAck.Dhcpv4.BootpSiAddr, 4);
- memcpy(full_path, template, strlen(template));
-
- /* Note we don't capture the filename option here because we know its shim.efi
- * We instead assume the filename at the end of the path is going to be grubx64.efi
- */
return EFI_SUCCESS;
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-16 21:41:45 +0000