ipl_report.c

  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/init.h>
  3#include <linux/ctype.h>
  4#include <asm/ebcdic.h>
  5#include <asm/sclp.h>
  6#include <asm/sections.h>
  7#include <asm/boot_data.h>
  8#include <asm/physmem_info.h>
  9#include <uapi/asm/ipl.h>
 10#include "boot.h"
 11
 12int __bootdata_preserved(ipl_secure_flag);
 13
 14unsigned long __bootdata_preserved(ipl_cert_list_addr);
 15unsigned long __bootdata_preserved(ipl_cert_list_size);
 16
 17unsigned long __bootdata(early_ipl_comp_list_addr);
 18unsigned long __bootdata(early_ipl_comp_list_size);
 19
 20static struct ipl_rb_certificates *certs;
 21static struct ipl_rb_components *comps;
 22static bool ipl_report_needs_saving;
 23
 24#define for_each_rb_entry(entry, rb) \
 25	for (entry = rb->entries; \
 26	     (void *) entry + sizeof(*entry) <= (void *) rb + rb->len; \
 27	     entry++)
 28
 29static unsigned long get_cert_comp_list_size(void)
 30{
 31	struct ipl_rb_certificate_entry *cert;
 32	struct ipl_rb_component_entry *comp;
 33
 34	/*
 35	 * Find the length for the IPL report boot data
 36	 */
 37	early_ipl_comp_list_size = 0;
 38	for_each_rb_entry(comp, comps)
 39		early_ipl_comp_list_size += sizeof(*comp);
 40	ipl_cert_list_size = 0;
 41	for_each_rb_entry(cert, certs)
 42		ipl_cert_list_size += sizeof(unsigned int) + cert->len;
 43	return ipl_cert_list_size + early_ipl_comp_list_size;
 44}
 45
 46bool ipl_report_certs_intersects(unsigned long addr, unsigned long size,
 47				 unsigned long *intersection_start)
 48{
 49	struct ipl_rb_certificate_entry *cert;
 50
 51	if (!ipl_report_needs_saving)
 52		return false;
 53
 54	for_each_rb_entry(cert, certs) {
 55		if (intersects(addr, size, cert->addr, cert->len)) {
 56			*intersection_start = cert->addr;
 57			return true;
 58		}
 59	}
 60	return false;
 61}
 62
 63static void copy_components_bootdata(void)
 64{
 65	struct ipl_rb_component_entry *comp, *ptr;
 66
 67	ptr = (struct ipl_rb_component_entry *) early_ipl_comp_list_addr;
 68	for_each_rb_entry(comp, comps)
 69		memcpy(ptr++, comp, sizeof(*ptr));
 70}
 71
 72static void copy_certificates_bootdata(void)
 73{
 74	struct ipl_rb_certificate_entry *cert;
 75	void *ptr;
 76
 77	ptr = (void *) ipl_cert_list_addr;
 78	for_each_rb_entry(cert, certs) {
 79		*(unsigned int *) ptr = cert->len;
 80		ptr += sizeof(unsigned int);
 81		memcpy(ptr, (void *) cert->addr, cert->len);
 82		ptr += cert->len;
 83	}
 84}
 85
 86int read_ipl_report(void)
 87{
 88	struct ipl_pl_hdr *pl_hdr;
 89	struct ipl_rl_hdr *rl_hdr;
 90	struct ipl_rb_hdr *rb_hdr;
 91	unsigned long tmp;
 92	void *rl_end;
 93
 94	/*
 95	 * Check if there is a IPL report by looking at the copy
 96	 * of the IPL parameter information block.
 97	 */
 98	if (!ipl_block_valid ||
 99	    !(ipl_block.hdr.flags & IPL_PL_FLAG_IPLSR))
100		return -1;
101	ipl_secure_flag = !!(ipl_block.hdr.flags & IPL_PL_FLAG_SIPL);
102	/*
103	 * There is an IPL report, to find it load the pointer to the
104	 * IPL parameter information block from lowcore and skip past
105	 * the IPL parameter list, then align the address to a double
106	 * word boundary.
107	 */
108	tmp = (unsigned long)get_lowcore()->ipl_parmblock_ptr;
109	pl_hdr = (struct ipl_pl_hdr *) tmp;
110	tmp = (tmp + pl_hdr->len + 7) & -8UL;
111	rl_hdr = (struct ipl_rl_hdr *) tmp;
112	/* Walk through the IPL report blocks in the IPL Report list */
113	certs = NULL;
114	comps = NULL;
115	rl_end = (void *) rl_hdr + rl_hdr->len;
116	rb_hdr = (void *) rl_hdr + sizeof(*rl_hdr);
117	while ((void *) rb_hdr + sizeof(*rb_hdr) < rl_end &&
118	       (void *) rb_hdr + rb_hdr->len <= rl_end) {
119
120		switch (rb_hdr->rbt) {
121		case IPL_RBT_CERTIFICATES:
122			certs = (struct ipl_rb_certificates *) rb_hdr;
123			break;
124		case IPL_RBT_COMPONENTS:
125			comps = (struct ipl_rb_components *) rb_hdr;
126			break;
127		default:
128			break;
129		}
130
131		rb_hdr = (void *) rb_hdr + rb_hdr->len;
132	}
133
134	/*
135	 * With either the component list or the certificate list
136	 * missing the kernel will stay ignorant of secure IPL.
137	 */
138	if (!comps || !certs) {
139		certs = NULL;
140		return -1;
141	}
142
143	ipl_report_needs_saving = true;
144	physmem_reserve(RR_IPLREPORT, (unsigned long)pl_hdr,
145			(unsigned long)rl_end - (unsigned long)pl_hdr);
146	return 0;
147}
148
149void save_ipl_cert_comp_list(void)
150{
151	unsigned long size;
152
153	if (!ipl_report_needs_saving)
154		return;
155
156	size = get_cert_comp_list_size();
157	early_ipl_comp_list_addr = physmem_alloc_or_die(RR_CERT_COMP_LIST, size, sizeof(int));
158	ipl_cert_list_addr = early_ipl_comp_list_addr + early_ipl_comp_list_size;
159
160	copy_components_bootdata();
161	copy_certificates_bootdata();
162	physmem_free(RR_IPLREPORT);
163	ipl_report_needs_saving = false;
164}