1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *
4  * Common security related functions for OMAP devices
5  *
6  * (C) Copyright 2016-2017
7  * Texas Instruments, <www.ti.com>
8  *
9  * Daniel Allred <d-allred@ti.com>
10  * Andreas Dannenberg <dannenberg@ti.com>
11  * Harinarayan Bhatta <harinarayan@ti.com>
12  * Andrew F. Davis <afd@ti.com>
13  */
14 
15 #include <common.h>
16 #include <command.h>
17 #include <cpu_func.h>
18 #include <hang.h>
19 #include <init.h>
20 #include <log.h>
21 #include <stdarg.h>
22 
23 #include <asm/arch/sys_proto.h>
24 #include <asm/cache.h>
25 #include <asm/omap_common.h>
26 #include <asm/omap_sec_common.h>
27 #include <asm/spl.h>
28 #include <asm/ti-common/sys_proto.h>
29 #include <mapmem.h>
30 #include <spl.h>
31 #include <tee/optee.h>
32 
33 /* Index for signature verify ROM API */
34 #ifdef CONFIG_AM33XX
35 #define API_HAL_KM_VERIFYCERTIFICATESIGNATURE_INDEX	(0x0000000C)
36 #else
37 #define API_HAL_KM_VERIFYCERTIFICATESIGNATURE_INDEX	(0x0000000E)
38 #endif
39 
40 /* Index for signature PPA-based TI HAL APIs */
41 #define PPA_HAL_SERVICES_START_INDEX        (0x200)
42 #define PPA_SERV_HAL_TEE_LOAD_MASTER        (PPA_HAL_SERVICES_START_INDEX + 23)
43 #define PPA_SERV_HAL_TEE_LOAD_SLAVE         (PPA_HAL_SERVICES_START_INDEX + 24)
44 #define PPA_SERV_HAL_SETUP_SEC_RESVD_REGION (PPA_HAL_SERVICES_START_INDEX + 25)
45 #define PPA_SERV_HAL_SETUP_EMIF_FW_REGION   (PPA_HAL_SERVICES_START_INDEX + 26)
46 #define PPA_SERV_HAL_LOCK_EMIF_FW           (PPA_HAL_SERVICES_START_INDEX + 27)
47 
48 /* Offset of header size if image is signed as ISW */
49 #define HEADER_SIZE_OFFSET	(0x6D)
50 
51 int tee_loaded = 0;
52 
53 /* Argument for PPA_SERV_HAL_TEE_LOAD_MASTER */
54 struct ppa_tee_load_info {
55 	u32 tee_sec_mem_start; /* Physical start address reserved for TEE */
56 	u32 tee_sec_mem_size;  /* Size of the memory reserved for TEE */
57 	u32 tee_cert_start;    /* Address where signed TEE binary is loaded */
58 	u32 tee_cert_size;     /* Size of TEE certificate (signed binary) */
59 	u32 tee_jump_addr;     /* Address to jump to start TEE execution */
60 	u32 tee_arg0;          /* argument to TEE jump function, in r0 */
61 };
62 
63 static uint32_t secure_rom_call_args[5] __aligned(ARCH_DMA_MINALIGN) __section(".data");
64 
secure_rom_call(u32 service,u32 proc_id,u32 flag,...)65 u32 secure_rom_call(u32 service, u32 proc_id, u32 flag, ...)
66 {
67 	int i;
68 	u32 num_args;
69 	va_list ap;
70 
71 	va_start(ap, flag);
72 
73 	num_args = va_arg(ap, u32);
74 
75 	if (num_args > 4) {
76 		va_end(ap);
77 		return 1;
78 	}
79 
80 	/* Copy args to aligned args structure */
81 	for (i = 0; i < num_args; i++)
82 		secure_rom_call_args[i + 1] = va_arg(ap, u32);
83 
84 	secure_rom_call_args[0] = num_args;
85 
86 	va_end(ap);
87 
88 	/* if data cache is enabled, flush the aligned args structure */
89 	flush_dcache_range(
90 		(unsigned int)&secure_rom_call_args[0],
91 		(unsigned int)&secure_rom_call_args[0] +
92 		roundup(sizeof(secure_rom_call_args), ARCH_DMA_MINALIGN));
93 
94 	return omap_smc_sec(service, proc_id, flag, secure_rom_call_args);
95 }
96 
find_sig_start(char * image,size_t size)97 static u32 find_sig_start(char *image, size_t size)
98 {
99 	char *image_end = image + size;
100 	char *sig_start_magic = "CERT_";
101 	int magic_str_len = strlen(sig_start_magic);
102 	char *ch;
103 
104 	while (--image_end > image) {
105 		if (*image_end == '_') {
106 			ch = image_end - magic_str_len + 1;
107 			if (!strncmp(ch, sig_start_magic, magic_str_len))
108 				return (u32)ch;
109 		}
110 	}
111 	return 0;
112 }
113 
secure_boot_verify_image(void ** image,size_t * size)114 int secure_boot_verify_image(void **image, size_t *size)
115 {
116 	int result = 1;
117 	u32 cert_addr, sig_addr;
118 	size_t cert_size;
119 
120 	/* Perform cache writeback on input buffer */
121 	flush_dcache_range(
122 		rounddown((u32)*image, ARCH_DMA_MINALIGN),
123 		roundup((u32)*image + *size, ARCH_DMA_MINALIGN));
124 
125 	cert_addr = (uint32_t)*image;
126 	sig_addr = find_sig_start((char *)*image, *size);
127 
128 	if (sig_addr == 0) {
129 		printf("No signature found in image!\n");
130 		result = 1;
131 		goto auth_exit;
132 	}
133 
134 	*size = sig_addr - cert_addr;	/* Subtract out the signature size */
135 	/* Subtract header if present */
136 	if (strncmp((char *)sig_addr, "CERT_ISW_", 9) == 0)
137 		*size -= ((u32 *)*image)[HEADER_SIZE_OFFSET];
138 	cert_size = *size;
139 
140 	/* Check if image load address is 32-bit aligned */
141 	if (!IS_ALIGNED(cert_addr, 4)) {
142 		printf("Image is not 4-byte aligned!\n");
143 		result = 1;
144 		goto auth_exit;
145 	}
146 
147 	/* Image size also should be multiple of 4 */
148 	if (!IS_ALIGNED(cert_size, 4)) {
149 		printf("Image size is not 4-byte aligned!\n");
150 		result = 1;
151 		goto auth_exit;
152 	}
153 
154 	/* Call ROM HAL API to verify certificate signature */
155 	debug("%s: load_addr = %x, size = %x, sig_addr = %x\n", __func__,
156 	      cert_addr, cert_size, sig_addr);
157 
158 	result = secure_rom_call(
159 		API_HAL_KM_VERIFYCERTIFICATESIGNATURE_INDEX, 0, 0,
160 		4, cert_addr, cert_size, sig_addr, 0xFFFFFFFF);
161 
162 	/* Perform cache writeback on output buffer */
163 	flush_dcache_range(
164 		rounddown((u32)*image, ARCH_DMA_MINALIGN),
165 		roundup((u32)*image + *size, ARCH_DMA_MINALIGN));
166 
167 auth_exit:
168 	if (result != 0) {
169 		printf("Authentication failed!\n");
170 		printf("Return Value = %08X\n", result);
171 		hang();
172 	}
173 
174 	/*
175 	 * Output notification of successful authentication to re-assure the
176 	 * user that the secure code is being processed as expected. However
177 	 * suppress any such log output in case of building for SPL and booting
178 	 * via YMODEM. This is done to avoid disturbing the YMODEM serial
179 	 * protocol transactions.
180 	 */
181 	if (!(IS_ENABLED(CONFIG_SPL_BUILD) &&
182 	      IS_ENABLED(CONFIG_SPL_YMODEM_SUPPORT) &&
183 	      spl_boot_device() == BOOT_DEVICE_UART))
184 		printf("Authentication passed\n");
185 
186 	return result;
187 }
188 
get_sec_mem_start(void)189 u32 get_sec_mem_start(void)
190 {
191 	u32 sec_mem_start = CONFIG_TI_SECURE_EMIF_REGION_START;
192 	u32 sec_mem_size = CONFIG_TI_SECURE_EMIF_TOTAL_REGION_SIZE;
193 	/*
194 	 * Total reserved region is all contiguous with protected
195 	 * region coming first, followed by the non-secure region.
196 	 * If 0x0 start address is given, we simply put the reserved
197 	 * region at the end of the external DRAM.
198 	 */
199 	if (sec_mem_start == 0)
200 		sec_mem_start =
201 			(CONFIG_SYS_SDRAM_BASE + (
202 #if defined(CONFIG_OMAP54XX)
203 			omap_sdram_size()
204 #else
205 			get_ram_size((void *)CONFIG_SYS_SDRAM_BASE,
206 				     CONFIG_MAX_RAM_BANK_SIZE)
207 #endif
208 			- sec_mem_size));
209 	return sec_mem_start;
210 }
211 
secure_emif_firewall_setup(uint8_t region_num,uint32_t start_addr,uint32_t size,uint32_t access_perm,uint32_t initiator_perm)212 int secure_emif_firewall_setup(uint8_t region_num, uint32_t start_addr,
213 			       uint32_t size, uint32_t access_perm,
214 			       uint32_t initiator_perm)
215 {
216 	int result = 1;
217 
218 	/*
219 	 * Call PPA HAL API to do any other general firewall
220 	 * configuration for regions 1-6 of the EMIF firewall.
221 	 */
222 	debug("%s: regionNum = %x, startAddr = %x, size = %x", __func__,
223 	      region_num, start_addr, size);
224 
225 	result = secure_rom_call(
226 			PPA_SERV_HAL_SETUP_EMIF_FW_REGION, 0, 0, 4,
227 			(start_addr & 0xFFFFFFF0) | (region_num & 0x0F),
228 			size, access_perm, initiator_perm);
229 
230 	if (result != 0) {
231 		puts("Secure EMIF Firewall Setup failed!\n");
232 		debug("Return Value = %x\n", result);
233 	}
234 
235 	return result;
236 }
237 
238 #if	(CONFIG_TI_SECURE_EMIF_TOTAL_REGION_SIZE <  \
239 	CONFIG_TI_SECURE_EMIF_PROTECTED_REGION_SIZE)
240 #error	"TI Secure EMIF: Protected size cannot be larger than total size."
241 #endif
secure_emif_reserve(void)242 int secure_emif_reserve(void)
243 {
244 	int result = 1;
245 	u32 sec_mem_start = get_sec_mem_start();
246 	u32 sec_prot_size = CONFIG_TI_SECURE_EMIF_PROTECTED_REGION_SIZE;
247 
248 	/* If there is no protected region, there is no reservation to make */
249 	if (sec_prot_size == 0)
250 		return 0;
251 
252 	/*
253 	 * Call PPA HAL API to reserve a chunk of EMIF SDRAM
254 	 * for secure world use. This region should be carved out
255 	 * from use by any public code. EMIF firewall region 7
256 	 * will be used to protect this block of memory.
257 	 */
258 	result = secure_rom_call(
259 			PPA_SERV_HAL_SETUP_SEC_RESVD_REGION,
260 			0, 0, 2, sec_mem_start, sec_prot_size);
261 
262 	if (result != 0) {
263 		puts("SDRAM Firewall: Secure memory reservation failed!\n");
264 		debug("Return Value = %x\n", result);
265 	}
266 
267 	return result;
268 }
269 
secure_emif_firewall_lock(void)270 int secure_emif_firewall_lock(void)
271 {
272 	int result = 1;
273 
274 	/*
275 	 * Call PPA HAL API to lock the EMIF firewall configurations.
276 	 * After this API is called, none of the PPA HAL APIs for
277 	 * configuring the EMIF firewalls will be usable again (that
278 	 * is, calls to those APIs will return failure and have no
279 	 * effect).
280 	 */
281 
282 	result = secure_rom_call(
283 			PPA_SERV_HAL_LOCK_EMIF_FW,
284 			0, 0, 0);
285 
286 	if (result != 0) {
287 		puts("Secure EMIF Firewall Lock failed!\n");
288 		debug("Return Value = %x\n", result);
289 	}
290 
291 	return result;
292 }
293 
294 static struct ppa_tee_load_info tee_info __aligned(ARCH_DMA_MINALIGN);
295 
secure_tee_install(u32 addr)296 int secure_tee_install(u32 addr)
297 {
298 	struct optee_header *hdr;
299 	void *loadptr;
300 	u32 tee_file_size;
301 	u32 sec_mem_start = get_sec_mem_start();
302 	const u32 size = CONFIG_TI_SECURE_EMIF_PROTECTED_REGION_SIZE;
303 	u32 ret;
304 
305 	/* If there is no protected region, there is no place to put the TEE */
306 	if (size == 0) {
307 		printf("Error loading TEE, no protected memory region available\n");
308 		return -ENOBUFS;
309 	}
310 
311 	hdr = (struct optee_header *)map_sysmem(addr, sizeof(struct optee_header));
312 	/* 280 bytes = size of signature */
313 	tee_file_size = hdr->init_size + hdr->paged_size +
314 			sizeof(struct optee_header) + 280;
315 
316 	if ((hdr->magic != OPTEE_MAGIC) ||
317 	    (hdr->version != OPTEE_VERSION) ||
318 	    (tee_file_size > size)) {
319 		printf("Error in TEE header. Check firewall and TEE sizes\n");
320 		unmap_sysmem(hdr);
321 		return CMD_RET_FAILURE;
322 	}
323 
324 	tee_info.tee_sec_mem_start = sec_mem_start;
325 	tee_info.tee_sec_mem_size = size;
326 	tee_info.tee_jump_addr = hdr->init_load_addr_lo;
327 	tee_info.tee_cert_start = addr;
328 	tee_info.tee_cert_size = tee_file_size;
329 	tee_info.tee_arg0 = hdr->init_size + tee_info.tee_jump_addr;
330 	unmap_sysmem(hdr);
331 	loadptr = map_sysmem(addr, tee_file_size);
332 
333 	debug("tee_info.tee_sec_mem_start= %08X\n", tee_info.tee_sec_mem_start);
334 	debug("tee_info.tee_sec_mem_size = %08X\n", tee_info.tee_sec_mem_size);
335 	debug("tee_info.tee_jump_addr = %08X\n", tee_info.tee_jump_addr);
336 	debug("tee_info.tee_cert_start = %08X\n", tee_info.tee_cert_start);
337 	debug("tee_info.tee_cert_size = %08X\n", tee_info.tee_cert_size);
338 	debug("tee_info.tee_arg0 = %08X\n", tee_info.tee_arg0);
339 	debug("tee_file_size = %d\n", tee_file_size);
340 
341 #if !CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
342 	flush_dcache_range(
343 		rounddown((u32)loadptr, ARCH_DMA_MINALIGN),
344 		roundup((u32)loadptr + tee_file_size, ARCH_DMA_MINALIGN));
345 
346 	flush_dcache_range((u32)&tee_info, (u32)&tee_info +
347 			roundup(sizeof(tee_info), ARCH_DMA_MINALIGN));
348 #endif
349 	unmap_sysmem(loadptr);
350 
351 	ret = secure_rom_call(PPA_SERV_HAL_TEE_LOAD_MASTER, 0, 0, 1, &tee_info);
352 	if (ret) {
353 		printf("TEE_LOAD_MASTER Failed\n");
354 		return ret;
355 	}
356 	printf("TEE_LOAD_MASTER Done\n");
357 
358 #if defined(CONFIG_OMAP54XX)
359 	if (!is_dra72x()) {
360 		u32 *smc_cpu1_params;
361 		/* Reuse the tee_info buffer for SMC params */
362 		smc_cpu1_params = (u32 *)&tee_info;
363 		smc_cpu1_params[0] = 0;
364 #if !CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
365 		flush_dcache_range((u32)smc_cpu1_params, (u32)smc_cpu1_params +
366 				roundup(sizeof(u32), ARCH_DMA_MINALIGN));
367 #endif
368 		ret = omap_smc_sec_cpu1(PPA_SERV_HAL_TEE_LOAD_SLAVE, 0, 0,
369 				smc_cpu1_params);
370 		if (ret) {
371 			printf("TEE_LOAD_SLAVE Failed\n");
372 			return ret;
373 		}
374 		printf("TEE_LOAD_SLAVE Done\n");
375 	}
376 #endif
377 
378 	tee_loaded = 1;
379 
380 	return 0;
381 }
382