Freescale's SEC block has built-in Blob Protocol which provides a method for protecting user-defined data across system power cycles. SEC block protects data in a data structure called a Blob, which provides both confidentiality and integrity protection.

Encapsulating data as a blob Each time that the Blob Protocol is used to protect data, a different randomly generated key is used to encrypt the data. This random key is itself encrypted using a key which is derived from SoC's non volatile secret key and a 16 bit Key identifier. The resulting encrypted key along with encrypted data is called a blob. The non volatile secure key is available for use only during secure boot.

During decapsulation, the reverse process is performed to get back the original data.

Commands added -------------- blob enc - encapsulating data as a cryptgraphic blob blob dec - decapsulating cryptgraphic blob to get the data

Commands Syntax --------------- blob enc src dst len km

Encapsulate and create blob of data $len bytes long at address $src and store the result at address $dst. $km is the 16 byte key modifier is also required for generation/use as key for cryptographic operation. Key modifier should be 16 byte long.

blob dec src dst len km

Decapsulate the blob of data at address $src and store result of $len byte at addr $dst. $km is the 16 byte key modifier is also required for generation/use as key for cryptographic operation. Key modifier should be 16 byte long.

Signed-off-by: Ruchika Gupta ruchika.gupta@freescale.com --- Changes from v3 No changes

common/Makefile | 2 + common/cmd_blob.c | 109 ++++++++++++++++++++++++++++++++++++ drivers/crypto/fsl/Makefile | 1 + drivers/crypto/fsl/fsl_blob.c | 61 ++++++++++++++++++++ drivers/crypto/fsl/jobdesc.c | 80 ++++++++++++++++++++++++++ drivers/crypto/fsl/jobdesc.h | 11 ++++ drivers/crypto/fsl/jr.c | 127 +++++++++++++++++++++++++++++++++++++++++- include/fsl_sec.h | 34 ++++++++++- 8 files changed, 423 insertions(+), 2 deletions(-) create mode 100644 common/cmd_blob.c create mode 100644 drivers/crypto/fsl/fsl_blob.c

diff --git a/common/Makefile b/common/Makefile index b19d379..c84b3bc 100644 --- a/common/Makefile +++ b/common/Makefile @@ -265,4 +265,6 @@ obj-y += aboot.o obj-y += fb_mmc.o endif

+obj-$(CONFIG_CMD_BLOB) += cmd_blob.o + CFLAGS_env_embedded.o := -Wa,--no-warn -DENV_CRC=$(shell tools/envcrc 2>/dev/null) diff --git a/common/cmd_blob.c b/common/cmd_blob.c new file mode 100644 index 0000000..82ecaf0 --- /dev/null +++ b/common/cmd_blob.c @@ -0,0 +1,109 @@ +/* + * + * Command for encapsulating/decapsulating blob of memory. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <command.h> +#include <environment.h> +#include <malloc.h> +#include <asm/byteorder.h> +#include <linux/compiler.h> + +DECLARE_GLOBAL_DATA_PTR; + +/** + * blob_decap() - Decapsulate the data as a blob + * @key_mod: - Pointer to key modifier/key + * @src: - Address of data to be decapsulated + * @dst: - Address of data to be decapsulated + * @len: - Size of data to be decapsulated + * + * Returns zero on success,and negative on error. + */ +__weak int blob_decap(u8 *key_mod, u8 *src, u8 *dst, u32 len) +{ + return 0; +} + +/** + * blob_encap() - Encapsulate the data as a blob + * @key_mod: - Pointer to key modifier/key + * @src: - Address of data to be encapsulated + * @dst: - Address of data to be encapsulated + * @len: - Size of data to be encapsulated + * + * Returns zero on success,and negative on error. + */ +__weak int blob_encap(u8 *key_mod, u8 *src, u8 *dst, u32 len) +{ + return 0; +} + +/** + * do_blob() - Handle the "blob" command-line command + * @cmdtp: Command data struct pointer + * @flag: Command flag + * @argc: Command-line argument count + * @argv: Array of command-line arguments + * + * Returns zero on success, CMD_RET_USAGE in case of misuse and negative + * on error. + */ +static int do_blob(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]) +{ + uint32_t key_addr, src_addr, dst_addr, len; + uint8_t *km_ptr, *src_ptr, *dst_ptr; + int enc, ret = 0; + + if (argc != 6) + return CMD_RET_USAGE; + + if (!strncmp(argv[1], "enc", 3)) + enc = 1; + else if (!strncmp(argv[1], "dec", 3)) + enc = 0; + else + return CMD_RET_USAGE; + + src_addr = simple_strtoul(argv[2], NULL, 16); + dst_addr = simple_strtoul(argv[3], NULL, 16); + len = simple_strtoul(argv[4], NULL, 16); + key_addr = simple_strtoul(argv[5], NULL, 16); + + km_ptr = (uint8_t *)key_addr; + src_ptr = (uint8_t *)src_addr; + dst_ptr = (uint8_t *)dst_addr; + + if (enc) + ret = blob_encap(km_ptr, src_ptr, dst_ptr, len); + else + ret = blob_decap(km_ptr, src_ptr, dst_ptr, len); + + return ret; +} + +/***************************************************/ +static char blob_help_text[] = + "enc src dst len km - Encapsulate and create blob of data\n" + " $len bytes long at address $src and\n" + " store the result at address $dst.\n" + " $km is the 16 byte key modifier\n" + " is also required for generation/use as\n" + " key for cryptographic operation. Key\n" + " modifier should be 16 byte long.\n" + "blob dec src dst len km - Decapsulate the blob of data at address\n" + " $src and store result of $len byte at\n" + " addr $dst.\n" + " $km is the 16 byte key modifier\n" + " is also required for generation/use as\n" + " key for cryptographic operation. Key\n" + " modifier should be 16 byte long.\n"; + +U_BOOT_CMD( + blob, 6, 1, do_blob, + "Blob encapsulation/decryption", + blob_help_text +); diff --git a/drivers/crypto/fsl/Makefile b/drivers/crypto/fsl/Makefile index 59d9651..cb13d2e 100644 --- a/drivers/crypto/fsl/Makefile +++ b/drivers/crypto/fsl/Makefile @@ -7,3 +7,4 @@ #

obj-$(CONFIG_FSL_CAAM) += jr.o fsl_hash.o jobdesc.o error.o +obj-$(CONFIG_CMD_BLOB) += fsl_blob.o diff --git a/drivers/crypto/fsl/fsl_blob.c b/drivers/crypto/fsl/fsl_blob.c new file mode 100644 index 0000000..bc01075 --- /dev/null +++ b/drivers/crypto/fsl/fsl_blob.c @@ -0,0 +1,61 @@ +/* + * Copyright 2014 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + * + */ + +#include <common.h> +#include <malloc.h> +#include "jobdesc.h" +#include "desc.h" +#include "jr.h" + +int blob_decrypt(u8 *key_mod, u8 *src, u8 *dst, u8 len) +{ + int ret, i = 0; + u32 *desc; + + printf("\nDecapsulating data to form blob\n"); + desc = malloc(sizeof(int) * MAX_CAAM_DESCSIZE); + if (!desc) { + debug("Not enough memory for descriptor allocation\n"); + return -1; + } + + inline_cnstr_jobdesc_blob_decap(desc, key_mod, src, dst, len); + + for (i = 0; i < 14; i++) + printf("%x\n", *(desc + i)); + ret = run_descriptor_jr(desc); + + if (ret) + printf("Error in Decapsulation %d\n", ret); + + free(desc); + return ret; +} + +int blob_encrypt(u8 *key_mod, u8 *src, u8 *dst, u8 len) +{ + int ret, i = 0; + u32 *desc; + + printf("\nEncapsulating data to form blob\n"); + desc = malloc(sizeof(int) * MAX_CAAM_DESCSIZE); + if (!desc) { + debug("Not enough memory for descriptor allocation\n"); + return -1; + } + + inline_cnstr_jobdesc_blob_encap(desc, key_mod, src, dst, len); + for (i = 0; i < 14; i++) + printf("%x\n", *(desc + i)); + ret = run_descriptor_jr(desc); + + if (ret) + printf("Error in Encapsulation %d\n", ret); + + free(desc); + return ret; +} diff --git a/drivers/crypto/fsl/jobdesc.c b/drivers/crypto/fsl/jobdesc.c index cbe5c30..1386bae 100644 --- a/drivers/crypto/fsl/jobdesc.c +++ b/drivers/crypto/fsl/jobdesc.c @@ -12,6 +12,9 @@ #include "desc_constr.h" #include "jobdesc.h"

+#define KEY_BLOB_SIZE 32 +#define MAC_SIZE 16 + void inline_cnstr_jobdesc_hash(uint32_t *desc, const uint8_t *msg, uint32_t msgsz, uint8_t *digest, u32 alg_type, uint32_t alg_size, int sg_tbl) @@ -43,3 +46,80 @@ void inline_cnstr_jobdesc_hash(uint32_t *desc, append_store(desc, dma_addr_out, storelen, LDST_CLASS_2_CCB | LDST_SRCDST_BYTE_CONTEXT); } + +void inline_cnstr_jobdesc_blob_encap(uint32_t *desc, uint8_t *key_idnfr, + uint8_t *plain_txt, uint8_t *enc_blob, + uint32_t in_sz) +{ + dma_addr_t dma_addr_key_idnfr, dma_addr_in, dma_addr_out; + uint32_t key_sz = KEY_IDNFR_SZ_BYTES; + /* output blob will have 32 bytes key blob in beginning and + * 16 byte HMAC identifier at end of data blob */ + uint32_t out_sz = in_sz + KEY_BLOB_SIZE + MAC_SIZE; + + dma_addr_key_idnfr = virt_to_phys((void *)key_idnfr); + dma_addr_in = virt_to_phys((void *)plain_txt); + dma_addr_out = virt_to_phys((void *)enc_blob); + + init_job_desc(desc, 0); + + append_key(desc, dma_addr_key_idnfr, key_sz, CLASS_2); + + append_seq_in_ptr(desc, dma_addr_in, in_sz, 0); + + append_seq_out_ptr(desc, dma_addr_out, out_sz, 0); + + append_operation(desc, OP_TYPE_ENCAP_PROTOCOL | OP_PCLID_BLOB); +} + +void inline_cnstr_jobdesc_blob_decap(uint32_t *desc, uint8_t *key_idnfr, + uint8_t *enc_blob, uint8_t *plain_txt, + uint32_t out_sz) +{ + dma_addr_t dma_addr_key_idnfr, dma_addr_in, dma_addr_out; + uint32_t key_sz = KEY_IDNFR_SZ_BYTES; + uint32_t in_sz = out_sz + KEY_BLOB_SIZE + MAC_SIZE; + + dma_addr_key_idnfr = virt_to_phys((void *)key_idnfr); + dma_addr_in = virt_to_phys((void *)enc_blob); + dma_addr_out = virt_to_phys((void *)plain_txt); + + init_job_desc(desc, 0); + + append_key(desc, dma_addr_key_idnfr, key_sz, CLASS_2); + + append_seq_in_ptr(desc, dma_addr_in, in_sz, 0); + + append_seq_out_ptr(desc, dma_addr_out, out_sz, 0); + + append_operation(desc, OP_TYPE_DECAP_PROTOCOL | OP_PCLID_BLOB); +} + +/* + * Descriptor to instantiate RNG State Handle 0 in normal mode and + * load the JDKEK, TDKEK and TDSK registers + */ +void inline_cnstr_jobdesc_rng_instantiation(uint32_t *desc) +{ + u32 *jump_cmd; + + init_job_desc(desc, 0); + + /* INIT RNG in non-test mode */ + append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG | + OP_ALG_AS_INIT); + + /* wait for done */ + jump_cmd = append_jump(desc, JUMP_CLASS_CLASS1); + set_jump_tgt_here(desc, jump_cmd); + + /* + * load 1 to clear written reg: + * resets the done interrrupt and returns the RNG to idle. + */ + append_load_imm_u32(desc, 1, LDST_SRCDST_WORD_CLRW); + + /* generate secure keys (non-test) */ + append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG | + OP_ALG_RNG4_SK); +} diff --git a/drivers/crypto/fsl/jobdesc.h b/drivers/crypto/fsl/jobdesc.h index ed61579..3cf7226 100644 --- a/drivers/crypto/fsl/jobdesc.h +++ b/drivers/crypto/fsl/jobdesc.h @@ -11,8 +11,19 @@ #include <common.h> #include <asm/io.h>

+#define KEY_IDNFR_SZ_BYTES 16 + void inline_cnstr_jobdesc_hash(uint32_t *desc, const uint8_t *msg, uint32_t msgsz, uint8_t *digest, u32 alg_type, uint32_t alg_size, int sg_tbl);

+void inline_cnstr_jobdesc_blob_encap(uint32_t *desc, uint8_t *key_idnfr, + uint8_t *plain_txt, uint8_t *enc_blob, + uint32_t in_sz); + +void inline_cnstr_jobdesc_blob_decap(uint32_t *desc, uint8_t *key_idnfr, + uint8_t *enc_blob, uint8_t *plain_txt, + uint32_t out_sz); + +void inline_cnstr_jobdesc_rng_instantiation(uint32_t *desc); #endif diff --git a/drivers/crypto/fsl/jr.c b/drivers/crypto/fsl/jr.c index a107e6a..29681e1 100644 --- a/drivers/crypto/fsl/jr.c +++ b/drivers/crypto/fsl/jr.c @@ -10,6 +10,7 @@ #include <malloc.h> #include "fsl_sec.h" #include "jr.h" +#include "jobdesc.h"

#define CIRC_CNT(head, tail, size) (((head) - (tail)) & (size - 1)) #define CIRC_SPACE(head, tail, size) CIRC_CNT((tail), (head) + 1, (size)) @@ -319,6 +320,120 @@ int sec_reset(void) return 0; }

+static int instantiate_rng(void) +{ + struct result op; + u32 *desc; + u32 rdsta_val; + int ret = 0; + ccsr_sec_t __iomem *sec = + (ccsr_sec_t __iomem *)CONFIG_SYS_FSL_SEC_ADDR; + struct rng4tst __iomem *rng = + (struct rng4tst __iomem *)&sec->rng; + + memset(&op, 0, sizeof(struct result)); + + desc = malloc(sizeof(int) * 6); + if (!desc) { + printf("cannot allocate RNG init descriptor memory\n"); + return -1; + } + + inline_cnstr_jobdesc_rng_instantiation(desc); + ret = run_descriptor_jr(desc); + + if (ret) + printf("RNG: Instantiation failed with error %x\n", ret); + + rdsta_val = sec_in32(&rng->rdsta); + if (op.status || !(rdsta_val & RNG_STATE0_HANDLE_INSTANTIATED)) + return -1; + + return ret; +} + +static u8 get_rng_vid(void) +{ + ccsr_sec_t *sec = (void *)CONFIG_SYS_FSL_SEC_ADDR; + u32 cha_vid = sec_in32(&sec->chavid_ls); + + return (cha_vid & SEC_CHAVID_RNG_LS_MASK) >> SEC_CHAVID_LS_RNG_SHIFT; +} + +/* + * By default, the TRNG runs for 200 clocks per sample; + * 1200 clocks per sample generates better entropy. + */ +static void kick_trng(int ent_delay) +{ + ccsr_sec_t __iomem *sec = + (ccsr_sec_t __iomem *)CONFIG_SYS_FSL_SEC_ADDR; + struct rng4tst __iomem *rng = + (struct rng4tst __iomem *)&sec->rng; + u32 val; + + /* put RNG4 into program mode */ + sec_setbits32(&rng->rtmctl, RTMCTL_PRGM); + /* rtsdctl bits 0-15 contain "Entropy Delay, which defines the + * length (in system clocks) of each Entropy sample taken + * */ + val = sec_in32(&rng->rtsdctl); + val = (val & ~RTSDCTL_ENT_DLY_MASK) | + (ent_delay << RTSDCTL_ENT_DLY_SHIFT); + sec_out32(&rng->rtsdctl, val); + /* min. freq. count, equal to 1/4 of the entropy sample length */ + sec_out32(&rng->rtfreqmin, ent_delay >> 2); + /* max. freq. count, equal to 8 times the entropy sample length */ + sec_out32(&rng->rtfreqmax, ent_delay << 3); + /* put RNG4 into run mode */ + sec_clrbits32(&rng->rtmctl, RTMCTL_PRGM); +} + +static int rng_init(void) +{ + int ret, ent_delay = RTSDCTL_ENT_DLY_MIN; + ccsr_sec_t __iomem *sec = + (ccsr_sec_t __iomem *)CONFIG_SYS_FSL_SEC_ADDR; + struct rng4tst __iomem *rng = + (struct rng4tst __iomem *)&sec->rng; + + u32 rdsta = sec_in32(&rng->rdsta); + + /* Check if RNG state 0 handler is already instantiated */ + if (rdsta & RNG_STATE0_HANDLE_INSTANTIATED) + return 0; + + do { + /* + * If either of the SH's were instantiated by somebody else + * then it is assumed that the entropy + * parameters are properly set and thus the function + * setting these (kick_trng(...)) is skipped. + * Also, if a handle was instantiated, do not change + * the TRNG parameters. + */ + kick_trng(ent_delay); + ent_delay += 400; + /* + * if instantiate_rng(...) fails, the loop will rerun + * and the kick_trng(...) function will modfiy the + * upper and lower limits of the entropy sampling + * interval, leading to a sucessful initialization of + * the RNG. + */ + ret = instantiate_rng(); + } while ((ret == -1) && (ent_delay < RTSDCTL_ENT_DLY_MAX)); + if (ret) { + printf("RNG: Failed to instantiate RNG\n"); + return ret; + } + + /* Enable RDB bit so that RNG works faster */ + sec_setbits32(&sec->scfgr, SEC_SCFGR_RDBENABLE); + + return ret; +} + int sec_init(void) { int ret = 0; @@ -330,8 +445,18 @@ int sec_init(void) sec_out32(&sec->mcfgr, mcr | 1 << MCFGR_PS_SHIFT); #endif ret = jr_init(); - if (ret < 0) + if (ret < 0) { + printf("SEC initialization failed\n"); return -1; + } + + if (get_rng_vid() >= 4) { + if (rng_init() < 0) { + printf("RNG instantiation failed\n"); + return -1; + } + printf("SEC: RNG instantiated\n"); + }

return ret; } diff --git a/include/fsl_sec.h b/include/fsl_sec.h index 2a26d85..aa850a3 100644 --- a/include/fsl_sec.h +++ b/include/fsl_sec.h @@ -29,6 +29,36 @@

/* Security Engine Block (MS = Most Sig., LS = Least Sig.) */ #if CONFIG_SYS_FSL_SEC_COMPAT >= 4 +/* RNG4 TRNG test registers */ +struct rng4tst { +#define RTMCTL_PRGM 0x00010000 /* 1 -> program mode, 0 -> run mode */ + u32 rtmctl; /* misc. control register */ + u32 rtscmisc; /* statistical check misc. register */ + u32 rtpkrrng; /* poker range register */ +#define RTSDCTL_ENT_DLY_MIN 1200 +#define RTSDCTL_ENT_DLY_MAX 12800 + union { + u32 rtpkrmax; /* PRGM=1: poker max. limit register */ + u32 rtpkrsq; /* PRGM=0: poker square calc. result register */ + }; +#define RTSDCTL_ENT_DLY_SHIFT 16 +#define RTSDCTL_ENT_DLY_MASK (0xffff << RTSDCTL_ENT_DLY_SHIFT) + u32 rtsdctl; /* seed control register */ + union { + u32 rtsblim; /* PRGM=1: sparse bit limit register */ + u32 rttotsam; /* PRGM=0: total samples register */ + }; + u32 rtfreqmin; /* frequency count min. limit register */ + union { + u32 rtfreqmax; /* PRGM=1: freq. count max. limit register */ + u32 rtfreqcnt; /* PRGM=0: freq. count register */ + }; + u32 rsvd1[40]; +#define RNG_STATE0_HANDLE_INSTANTIATED 0x00000001 + u32 rdsta; /*RNG DRNG Status Register*/ + u32 rsvd2[15]; +}; + typedef struct ccsr_sec { u32 res0; u32 mcfgr; /* Master CFG Register */ @@ -53,7 +83,9 @@ typedef struct ccsr_sec { u8 res4[0x40]; u32 dar; /* DECO Avail Register */ u32 drr; /* DECO Reset Register */ - u8 res5[0xe78]; + u8 res5[0x4d8]; + struct rng4tst rng; /* RNG Registers */ + u8 res11[0x8a0]; u32 crnr_ms; /* CHA Revision Number Register, MS */ u32 crnr_ls; /* CHA Revision Number Register, LS */ u32 ctpr_ms; /* Compile Time Parameters Register, MS */