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