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 <uapi/asm/ipl.h>
9 #include "boot.h"
10
11 int __bootdata_preserved(ipl_secure_flag);
12
13 unsigned long __bootdata_preserved(ipl_cert_list_addr);
14 unsigned long __bootdata_preserved(ipl_cert_list_size);
15
16 unsigned long __bootdata(early_ipl_comp_list_addr);
17 unsigned long __bootdata(early_ipl_comp_list_size);
18
19 #define for_each_rb_entry(entry, rb) \
20 for (entry = rb->entries; \
21 (void *) entry + sizeof(*entry) <= (void *) rb + rb->len; \
22 entry++)
23
intersects(unsigned long addr0,unsigned long size0,unsigned long addr1,unsigned long size1)24 static inline bool intersects(unsigned long addr0, unsigned long size0,
25 unsigned long addr1, unsigned long size1)
26 {
27 return addr0 + size0 > addr1 && addr1 + size1 > addr0;
28 }
29
find_bootdata_space(struct ipl_rb_components * comps,struct ipl_rb_certificates * certs,unsigned long safe_addr)30 static unsigned long find_bootdata_space(struct ipl_rb_components *comps,
31 struct ipl_rb_certificates *certs,
32 unsigned long safe_addr)
33 {
34 struct ipl_rb_certificate_entry *cert;
35 struct ipl_rb_component_entry *comp;
36 size_t size;
37
38 /*
39 * Find the length for the IPL report boot data
40 */
41 early_ipl_comp_list_size = 0;
42 for_each_rb_entry(comp, comps)
43 early_ipl_comp_list_size += sizeof(*comp);
44 ipl_cert_list_size = 0;
45 for_each_rb_entry(cert, certs)
46 ipl_cert_list_size += sizeof(unsigned int) + cert->len;
47 size = ipl_cert_list_size + early_ipl_comp_list_size;
48
49 /*
50 * Start from safe_addr to find a free memory area large
51 * enough for the IPL report boot data. This area is used
52 * for ipl_cert_list_addr/ipl_cert_list_size and
53 * early_ipl_comp_list_addr/early_ipl_comp_list_size. It must
54 * not overlap with any component or any certificate.
55 */
56 repeat:
57 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && INITRD_START && INITRD_SIZE &&
58 intersects(INITRD_START, INITRD_SIZE, safe_addr, size))
59 safe_addr = INITRD_START + INITRD_SIZE;
60 for_each_rb_entry(comp, comps)
61 if (intersects(safe_addr, size, comp->addr, comp->len)) {
62 safe_addr = comp->addr + comp->len;
63 goto repeat;
64 }
65 for_each_rb_entry(cert, certs)
66 if (intersects(safe_addr, size, cert->addr, cert->len)) {
67 safe_addr = cert->addr + cert->len;
68 goto repeat;
69 }
70 early_ipl_comp_list_addr = safe_addr;
71 ipl_cert_list_addr = safe_addr + early_ipl_comp_list_size;
72
73 return safe_addr + size;
74 }
75
copy_components_bootdata(struct ipl_rb_components * comps)76 static void copy_components_bootdata(struct ipl_rb_components *comps)
77 {
78 struct ipl_rb_component_entry *comp, *ptr;
79
80 ptr = (struct ipl_rb_component_entry *) early_ipl_comp_list_addr;
81 for_each_rb_entry(comp, comps)
82 memcpy(ptr++, comp, sizeof(*ptr));
83 }
84
copy_certificates_bootdata(struct ipl_rb_certificates * certs)85 static void copy_certificates_bootdata(struct ipl_rb_certificates *certs)
86 {
87 struct ipl_rb_certificate_entry *cert;
88 void *ptr;
89
90 ptr = (void *) ipl_cert_list_addr;
91 for_each_rb_entry(cert, certs) {
92 *(unsigned int *) ptr = cert->len;
93 ptr += sizeof(unsigned int);
94 memcpy(ptr, (void *) cert->addr, cert->len);
95 ptr += cert->len;
96 }
97 }
98
read_ipl_report(unsigned long safe_addr)99 unsigned long read_ipl_report(unsigned long safe_addr)
100 {
101 struct ipl_rb_certificates *certs;
102 struct ipl_rb_components *comps;
103 struct ipl_pl_hdr *pl_hdr;
104 struct ipl_rl_hdr *rl_hdr;
105 struct ipl_rb_hdr *rb_hdr;
106 unsigned long tmp;
107 void *rl_end;
108
109 /*
110 * Check if there is a IPL report by looking at the copy
111 * of the IPL parameter information block.
112 */
113 if (!ipl_block_valid ||
114 !(ipl_block.hdr.flags & IPL_PL_FLAG_IPLSR))
115 return safe_addr;
116 ipl_secure_flag = !!(ipl_block.hdr.flags & IPL_PL_FLAG_SIPL);
117 /*
118 * There is an IPL report, to find it load the pointer to the
119 * IPL parameter information block from lowcore and skip past
120 * the IPL parameter list, then align the address to a double
121 * word boundary.
122 */
123 tmp = (unsigned long) S390_lowcore.ipl_parmblock_ptr;
124 pl_hdr = (struct ipl_pl_hdr *) tmp;
125 tmp = (tmp + pl_hdr->len + 7) & -8UL;
126 rl_hdr = (struct ipl_rl_hdr *) tmp;
127 /* Walk through the IPL report blocks in the IPL Report list */
128 certs = NULL;
129 comps = NULL;
130 rl_end = (void *) rl_hdr + rl_hdr->len;
131 rb_hdr = (void *) rl_hdr + sizeof(*rl_hdr);
132 while ((void *) rb_hdr + sizeof(*rb_hdr) < rl_end &&
133 (void *) rb_hdr + rb_hdr->len <= rl_end) {
134
135 switch (rb_hdr->rbt) {
136 case IPL_RBT_CERTIFICATES:
137 certs = (struct ipl_rb_certificates *) rb_hdr;
138 break;
139 case IPL_RBT_COMPONENTS:
140 comps = (struct ipl_rb_components *) rb_hdr;
141 break;
142 default:
143 break;
144 }
145
146 rb_hdr = (void *) rb_hdr + rb_hdr->len;
147 }
148
149 /*
150 * With either the component list or the certificate list
151 * missing the kernel will stay ignorant of secure IPL.
152 */
153 if (!comps || !certs)
154 return safe_addr;
155
156 /*
157 * Copy component and certificate list to a safe area
158 * where the decompressed kernel can find them.
159 */
160 safe_addr = find_bootdata_space(comps, certs, safe_addr);
161 copy_components_bootdata(comps);
162 copy_certificates_bootdata(certs);
163
164 return safe_addr;
165 }
166