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Diffstat (limited to 'lib/efi_loader/efi_device_path.c')
-rw-r--r--lib/efi_loader/efi_device_path.c151
1 files changed, 137 insertions, 14 deletions
diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c
index c9315dd458..4b20859b25 100644
--- a/lib/efi_loader/efi_device_path.c
+++ b/lib/efi_loader/efi_device_path.c
@@ -282,11 +282,31 @@ struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp)
return ndp;
}
-struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
- const struct efi_device_path *dp2)
+/**
+ * efi_dp_append_or_concatenate() - Append or concatenate two device paths.
+ * Concatenated device path will be separated
+ * by a sub-type 0xff end node
+ *
+ * @dp1: First device path
+ * @dp2: Second device path
+ * @concat: If true the two device paths will be concatenated and separated
+ * by an end of entrire device path sub-type 0xff end node.
+ * If true the second device path will be appended to the first and
+ * terminated by an end node
+ *
+ * Return:
+ * concatenated device path or NULL. Caller must free the returned value
+ */
+static struct
+efi_device_path *efi_dp_append_or_concatenate(const struct efi_device_path *dp1,
+ const struct efi_device_path *dp2,
+ bool concat)
{
struct efi_device_path *ret;
+ size_t end_size = sizeof(END);
+ if (concat)
+ end_size = 2 * sizeof(END);
if (!dp1 && !dp2) {
/* return an end node */
ret = efi_dp_dup(&END);
@@ -298,18 +318,58 @@ struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
/* both dp1 and dp2 are non-null */
unsigned sz1 = efi_dp_size(dp1);
unsigned sz2 = efi_dp_size(dp2);
- void *p = dp_alloc(sz1 + sz2 + sizeof(END));
+ void *p = dp_alloc(sz1 + sz2 + end_size);
if (!p)
return NULL;
+ ret = p;
memcpy(p, dp1, sz1);
+ p += sz1;
+
+ if (concat) {
+ memcpy(p, &END, sizeof(END));
+ p += sizeof(END);
+ }
+
/* the end node of the second device path has to be retained */
- memcpy(p + sz1, dp2, sz2 + sizeof(END));
- ret = p;
+ memcpy(p, dp2, sz2);
+ p += sz2;
+ memcpy(p, &END, sizeof(END));
}
return ret;
}
+/**
+ * efi_dp_append() - Append a device to an existing device path.
+ *
+ * @dp1: First device path
+ * @dp2: Second device path
+ *
+ * Return:
+ * concatenated device path or NULL. Caller must free the returned value
+ */
+struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
+ const struct efi_device_path *dp2)
+{
+ return efi_dp_append_or_concatenate(dp1, dp2, false);
+}
+
+/**
+ * efi_dp_concat() - Concatenate 2 device paths. The final device path will
+ * contain two device paths separated by and end node (0xff).
+ *
+ * @dp1: First device path
+ * @dp2: Second device path
+ *
+ * Return:
+ * concatenated device path or NULL. Caller must free the returned value
+ */
+struct efi_device_path *efi_dp_concat(const struct efi_device_path *dp1,
+ const struct efi_device_path *dp2)
+{
+ return efi_dp_append_or_concatenate(dp1, dp2, true);
+}
+
struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
const struct efi_device_path *node)
{
@@ -960,6 +1020,28 @@ struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
return start;
}
+struct efi_device_path *efi_dp_from_uart(void)
+{
+ void *buf, *pos;
+ struct efi_device_path_uart *uart;
+ size_t dpsize = sizeof(ROOT) + sizeof(*uart) + sizeof(END);
+
+ buf = dp_alloc(dpsize);
+ if (!buf)
+ return NULL;
+ pos = buf;
+ memcpy(pos, &ROOT, sizeof(ROOT));
+ pos += sizeof(ROOT);
+ uart = pos;
+ uart->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
+ uart->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_UART;
+ uart->dp.length = sizeof(*uart);
+ pos += sizeof(*uart);
+ memcpy(pos, &END, sizeof(END));
+
+ return buf;
+}
+
#ifdef CONFIG_NET
struct efi_device_path *efi_dp_from_eth(void)
{
@@ -1086,7 +1168,6 @@ efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
struct efi_device_path **device,
struct efi_device_path **file)
{
- int is_net;
struct blk_desc *desc = NULL;
struct disk_partition fs_partition;
int part = 0;
@@ -1096,8 +1177,15 @@ efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
if (path && !file)
return EFI_INVALID_PARAMETER;
- is_net = !strcmp(dev, "Net");
- if (!is_net) {
+ if (!strcmp(dev, "Net")) {
+#ifdef CONFIG_NET
+ if (device)
+ *device = efi_dp_from_eth();
+#endif
+ } else if (!strcmp(dev, "Uart")) {
+ if (device)
+ *device = efi_dp_from_uart();
+ } else {
part = blk_get_device_part_str(dev, devnr, &desc, &fs_partition,
1);
if (part < 0 || !desc)
@@ -1105,11 +1193,6 @@ efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
if (device)
*device = efi_dp_from_part(desc, part);
- } else {
-#ifdef CONFIG_NET
- if (device)
- *device = efi_dp_from_eth();
-#endif
}
if (!path)
@@ -1120,7 +1203,7 @@ efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
s = filename;
while ((s = strchr(s, '/')))
*s++ = '\\';
- *file = efi_dp_from_file(is_net ? NULL : desc, part, filename);
+ *file = efi_dp_from_file(desc, part, filename);
if (!*file)
return EFI_INVALID_PARAMETER;
@@ -1160,3 +1243,43 @@ ssize_t efi_dp_check_length(const struct efi_device_path *dp,
dp = (const struct efi_device_path *)((const u8 *)dp + len);
}
}
+
+/**
+ * efi_dp_from_lo() - Get the instance of a VenMedia node in a
+ * multi-instance device path that matches
+ * a specific GUID. This kind of device paths
+ * is found in Boot#### options describing an
+ * initrd location
+ *
+ * @lo: EFI_LOAD_OPTION containing a valid device path
+ * @size: size of the discovered device path
+ * @guid: guid to search for
+ *
+ * Return:
+ * device path including the VenMedia node or NULL.
+ * Caller must free the returned value.
+ */
+struct
+efi_device_path *efi_dp_from_lo(struct efi_load_option *lo,
+ efi_uintn_t *size, efi_guid_t guid)
+{
+ struct efi_device_path *fp = lo->file_path;
+ struct efi_device_path_vendor *vendor;
+ int lo_len = lo->file_path_length;
+
+ for (; lo_len >= sizeof(struct efi_device_path);
+ lo_len -= fp->length, fp = (void *)fp + fp->length) {
+ if (lo_len < 0 || efi_dp_check_length(fp, lo_len) < 0)
+ break;
+ if (fp->type != DEVICE_PATH_TYPE_MEDIA_DEVICE ||
+ fp->sub_type != DEVICE_PATH_SUB_TYPE_VENDOR_PATH)
+ continue;
+
+ vendor = (struct efi_device_path_vendor *)fp;
+ if (!guidcmp(&vendor->guid, &guid))
+ return efi_dp_dup(fp);
+ }
+ log_debug("VenMedia(%pUl) not found in %ls\n", &guid, lo->label);
+
+ return NULL;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-06-02 03:15:16 +0000