[PULL 17/37] s390x/ipl: Introduce IPL Information Report Block (IIRB)

[Eric Farman <farman@linux.ibm.com>]

From: Zhuoying Cai <zycai@linux.ibm.com>

The IPL information report block (IIRB) contains information used
to locate IPL records and to report the results of signature verification
of one or more secure components of the load device.

IIRB is stored immediately following the IPL Parameter Block. Results on
component verification in any case (failure or success) are stored.

The IIRB data is reserved and protected by the guest kernel during early
boot to prevent it from being overwritten before the certificate data is
permanently saved.

Signed-off-by: Zhuoying Cai <zycai@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Link: https://lore.kernel.org/qemu-devel/20260730214624.2328883-16-zycai@linux.ibm.com
Signed-off-by: Eric Farman <farman@linux.ibm.com>
---
 docs/specs/s390x-secure-ipl.rst | 21 +++++++++++
 include/hw/s390x/ipl/qipl.h     | 62 +++++++++++++++++++++++++++++++++
 2 files changed, 83 insertions(+)

diff --git a/docs/specs/s390x-secure-ipl.rst b/docs/specs/s390x-secure-ipl.rst
index d8dcc77ba2..113acbeda9 100644
--- a/docs/specs/s390x-secure-ipl.rst
+++ b/docs/specs/s390x-secure-ipl.rst
@@ -101,3 +101,24 @@ Subcode 1 - perform signature verification
     * ``0x0302``: PKCS#7 format signature is invalid
     * ``0x0402``: signature-verification failed
     * ``0x0502``: length of Diag508SigVerifBlock is invalid
+
+IPL Information Report Block
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The IPL Parameter Block (IPLB), utilized for IPL operation, is extended with an
+IPL Information Report Block (IIRB), which contains the results from secure IPL
+operations such as:
+
+* component data
+* verification results
+* certificate data
+
+During early boot, the guest kernel reserves the memory region
+containing the IIRB. This preserves the data while the guest kernel is
+operating and during re-IPL.
+
+The guest kernel uses the contents in the IIRB for:
+
+* Boot logging: reports which components were loaded and verified.
+* kexec operations: builds the next kernel’s IPL report from the existing one.
+* Keying: installs IPL certificates into the platform trusted keyring.
diff --git a/include/hw/s390x/ipl/qipl.h b/include/hw/s390x/ipl/qipl.h
index 0ec6a6d1a7..571f831780 100644
--- a/include/hw/s390x/ipl/qipl.h
+++ b/include/hw/s390x/ipl/qipl.h
@@ -34,6 +34,9 @@ typedef enum S390IplType S390IplType;
 #define QEMU_DEFAULT_IPL S390_IPL_TYPE_CCW
 
 #define MAX_CERTIFICATES  64
+/* largest supported block size - same as VIRTIO_DASD_DEFAULT_BLOCK_SIZE */
+#define VIRTIO_MAX_BLOCK_SIZE   4096
+#define MAX_COMP_ENTRIES        ((VIRTIO_MAX_BLOCK_SIZE - 32) / 32)
 
 /*
  * The QEMU IPL Parameters will be stored at absolute address
@@ -148,4 +151,63 @@ union IplParameterBlock {
 } QEMU_PACKED;
 typedef union IplParameterBlock IplParameterBlock;
 
+struct IplInfoReportBlockHeader {
+    uint32_t len;
+    uint8_t  flags;
+    uint8_t  reserved1[11];
+};
+typedef struct IplInfoReportBlockHeader IplInfoReportBlockHeader;
+
+struct IplInfoBlockHeader {
+    uint32_t len;
+    uint8_t  type;
+    uint8_t  reserved1[11];
+};
+typedef struct IplInfoBlockHeader IplInfoBlockHeader;
+
+enum IplInfoBlockType {
+    IPL_INFO_BLOCK_TYPE_CERTIFICATES = 1,
+    IPL_INFO_BLOCK_TYPE_COMPONENTS = 2,
+};
+
+struct IplSignatureCertificateEntry {
+    uint64_t addr;
+    uint64_t len;
+};
+typedef struct IplSignatureCertificateEntry IplSignatureCertificateEntry;
+
+struct IplSignatureCertificateList {
+    IplInfoBlockHeader            ipl_info_header;
+    IplSignatureCertificateEntry  cert_entries[MAX_CERTIFICATES];
+};
+typedef struct IplSignatureCertificateList IplSignatureCertificateList;
+
+#define S390_IPL_DEV_COMP_FLAG_SC  0x80
+#define S390_IPL_DEV_COMP_FLAG_CSV 0x40
+
+struct IplDeviceComponentEntry {
+    uint64_t addr;
+    uint64_t len;
+    uint8_t  flags;
+    uint8_t  reserved1[5];
+    uint16_t cert_index;
+    uint8_t  reserved2[8];
+};
+typedef struct IplDeviceComponentEntry IplDeviceComponentEntry;
+
+struct IplDeviceComponentList {
+    IplInfoBlockHeader       ipl_info_header;
+    IplDeviceComponentEntry  device_entries[MAX_COMP_ENTRIES];
+};
+typedef struct IplDeviceComponentList IplDeviceComponentList;
+
+#define COMP_LIST_MAX   sizeof(IplDeviceComponentList)
+#define CERT_LIST_MAX   sizeof(IplSignatureCertificateList)
+
+struct IplInfoReportBlock {
+    IplInfoReportBlockHeader     hdr;
+    uint8_t                      info_blks[COMP_LIST_MAX + CERT_LIST_MAX];
+};
+typedef struct IplInfoReportBlock IplInfoReportBlock;
+
 #endif
-- 
2.55.0