From 94ba5e41402719ab8a58bf55b925867e50abcb35 Mon Sep 17 00:00:00 2001 From: Aneesh Bansal Date: Tue, 8 Dec 2015 14:14:13 +0530 Subject: SECURE BOOT: separate functions for reading keys Separate functions are created for reading and checking the sanity of Public keys: - read_validate_single_key - read_validate_ie_tbl - read_validate_srk_table Signed-off-by: Saksham Jain Signed-off-by: Aneesh Bansal Acked-by: Ruchika Gupta Reviewed-by: York Sun --- board/freescale/common/fsl_validate.c | 169 +++++++++++++++++++--------------- 1 file changed, 96 insertions(+), 73 deletions(-) (limited to 'board/freescale/common') diff --git a/board/freescale/common/fsl_validate.c b/board/freescale/common/fsl_validate.c index 282ce5391c..ef7a5aed3a 100644 --- a/board/freescale/common/fsl_validate.c +++ b/board/freescale/common/fsl_validate.c @@ -24,6 +24,10 @@ #define SHA256_NIBBLES (256/4) #define NUM_HEX_CHARS (sizeof(ulong) * 2) +#define CHECK_KEY_LEN(key_len) (((key_len) == 2 * KEY_SIZE_BYTES / 4) || \ + ((key_len) == 2 * KEY_SIZE_BYTES / 2) || \ + ((key_len) == 2 * KEY_SIZE_BYTES)) + /* This array contains DER value for SHA-256 */ static const u8 hash_identifier[] = { 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, @@ -179,20 +183,97 @@ static u32 is_key_revoked(u32 keynum, u32 rev_flag) return 0; } -/* It validates srk_table key lengths.*/ -static u32 validate_srk_tbl(struct srk_table *tbl, u32 num_entries) +/* It read validates srk_table key lengths.*/ +static u32 read_validate_srk_tbl(struct fsl_secboot_img_priv *img) { int i = 0; - for (i = 0; i < num_entries; i++) { - if (!((tbl[i].key_len == 2 * KEY_SIZE_BYTES/4) || - (tbl[i].key_len == 2 * KEY_SIZE_BYTES/2) || - (tbl[i].key_len == 2 * KEY_SIZE_BYTES))) + u32 ret, key_num, key_revoc_flag, size; + struct fsl_secboot_img_hdr *hdr = &img->hdr; + void *esbc = (u8 *)(uintptr_t)img->ehdrloc; + + if ((hdr->len_kr.num_srk == 0) || + (hdr->len_kr.num_srk > MAX_KEY_ENTRIES)) + return ERROR_ESBC_CLIENT_HEADER_INVALID_SRK_NUM_ENTRY; + + key_num = hdr->len_kr.srk_sel; + if (key_num == 0 || key_num > hdr->len_kr.num_srk) + return ERROR_ESBC_CLIENT_HEADER_INVALID_KEY_NUM; + + /* Get revoc key from sfp */ + key_revoc_flag = get_key_revoc(); + ret = is_key_revoked(key_num, key_revoc_flag); + if (ret) + return ERROR_ESBC_CLIENT_HEADER_KEY_REVOKED; + + size = hdr->len_kr.num_srk * sizeof(struct srk_table); + + memcpy(&img->srk_tbl, esbc + hdr->srk_tbl_off, size); + + for (i = 0; i < hdr->len_kr.num_srk; i++) { + if (!CHECK_KEY_LEN(img->srk_tbl[i].key_len)) return ERROR_ESBC_CLIENT_HEADER_INV_SRK_ENTRY_KEYLEN; } + + img->key_len = img->srk_tbl[key_num - 1].key_len; + + memcpy(&img->img_key, &(img->srk_tbl[key_num - 1].pkey), + img->key_len); + return 0; } #endif +static u32 read_validate_single_key(struct fsl_secboot_img_priv *img) +{ + struct fsl_secboot_img_hdr *hdr = &img->hdr; + void *esbc = (u8 *)(uintptr_t)img->ehdrloc; + + /* check key length */ + if (!CHECK_KEY_LEN(hdr->key_len)) + return ERROR_ESBC_CLIENT_HEADER_KEY_LEN; + + memcpy(&img->img_key, esbc + hdr->pkey, hdr->key_len); + + img->key_len = hdr->key_len; + + return 0; +} + +#if defined(CONFIG_FSL_ISBC_KEY_EXT) +static u32 read_validate_ie_tbl(struct fsl_secboot_img_priv *img) +{ + struct fsl_secboot_img_hdr *hdr = &img->hdr; + u32 ie_key_len, ie_revoc_flag, ie_num; + struct ie_key_info *ie_info; + + if (get_ie_info_addr(&img->ie_addr)) + return ERROR_IE_TABLE_NOT_FOUND; + ie_info = (struct ie_key_info *)(uintptr_t)img->ie_addr; + if (ie_info->num_keys == 0 || ie_info->num_keys > 32) + return ERROR_ESBC_CLIENT_HEADER_INVALID_IE_NUM_ENTRY; + + ie_num = hdr->ie_key_sel; + if (ie_num == 0 || ie_num > ie_info->num_keys) + return ERROR_ESBC_CLIENT_HEADER_INVALID_IE_KEY_NUM; + + ie_revoc_flag = ie_info->key_revok; + if ((u32)(1 << (ie_num - 1)) & ie_revoc_flag) + return ERROR_ESBC_CLIENT_HEADER_IE_KEY_REVOKED; + + ie_key_len = ie_info->ie_key_tbl[ie_num - 1].key_len; + + if (!CHECK_KEY_LEN(ie_key_len)) + return ERROR_ESBC_CLIENT_HEADER_INV_IE_ENTRY_KEYLEN; + + memcpy(&img->img_key, &(ie_info->ie_key_tbl[ie_num - 1].pkey), + ie_key_len); + + img->key_len = ie_key_len; + return 0; +} +#endif + + /* This function return length of public key.*/ static inline u32 get_key_len(struct fsl_secboot_img_priv *img) { @@ -541,13 +622,9 @@ static int read_validate_esbc_client_header(struct fsl_secboot_img_priv *img) struct fsl_secboot_img_hdr *hdr = &img->hdr; void *esbc = (u8 *)(uintptr_t)img->ehdrloc; u8 *k, *s; + u32 ret = 0; + #ifdef CONFIG_KEY_REVOCATION - u32 ret; - u32 key_num, key_revoc_flag, size; -#endif -#if defined(CONFIG_FSL_ISBC_KEY_EXT) - struct ie_key_info *ie_info; - u32 ie_num, ie_revoc_flag, ie_key_len; #endif int key_found = 0; @@ -568,80 +645,26 @@ static int read_validate_esbc_client_header(struct fsl_secboot_img_priv *img) /* Key checking*/ #ifdef CONFIG_KEY_REVOCATION if (check_srk(img)) { - if ((hdr->len_kr.num_srk == 0) || - (hdr->len_kr.num_srk > MAX_KEY_ENTRIES)) - return ERROR_ESBC_CLIENT_HEADER_INVALID_SRK_NUM_ENTRY; - - key_num = hdr->len_kr.srk_sel; - if (key_num == 0 || key_num > hdr->len_kr.num_srk) - return ERROR_ESBC_CLIENT_HEADER_INVALID_KEY_NUM; - - /* Get revoc key from sfp */ - key_revoc_flag = get_key_revoc(); - ret = is_key_revoked(key_num, key_revoc_flag); - if (ret) - return ERROR_ESBC_CLIENT_HEADER_KEY_REVOKED; - - size = hdr->len_kr.num_srk * sizeof(struct srk_table); - - memcpy(&img->srk_tbl, esbc + hdr->srk_tbl_off, size); - - ret = validate_srk_tbl(img->srk_tbl, hdr->len_kr.num_srk); - + ret = read_validate_srk_tbl(img); if (ret != 0) return ret; - - img->key_len = img->srk_tbl[key_num - 1].key_len; - - memcpy(&img->img_key, &(img->srk_tbl[key_num - 1].pkey), - img->key_len); - key_found = 1; } #endif #if defined(CONFIG_FSL_ISBC_KEY_EXT) if (!key_found && check_ie(img)) { - if (get_ie_info_addr(&img->ie_addr)) - return ERROR_IE_TABLE_NOT_FOUND; - ie_info = (struct ie_key_info *)(uintptr_t)img->ie_addr; - if (ie_info->num_keys == 0 || ie_info->num_keys > 32) - return ERROR_ESBC_CLIENT_HEADER_INVALID_IE_NUM_ENTRY; - - ie_num = hdr->ie_key_sel; - if (ie_num == 0 || ie_num > ie_info->num_keys) - return ERROR_ESBC_CLIENT_HEADER_INVALID_IE_KEY_NUM; - - ie_revoc_flag = ie_info->key_revok; - if ((u32)(1 << (ie_num - 1)) & ie_revoc_flag) - return ERROR_ESBC_CLIENT_HEADER_IE_KEY_REVOKED; - - ie_key_len = ie_info->ie_key_tbl[ie_num - 1].key_len; - - if (!((ie_key_len == 2 * KEY_SIZE_BYTES / 4) || - (ie_key_len == 2 * KEY_SIZE_BYTES / 2) || - (ie_key_len == 2 * KEY_SIZE_BYTES))) - return ERROR_ESBC_CLIENT_HEADER_INV_IE_ENTRY_KEYLEN; - - memcpy(&img->img_key, &(ie_info->ie_key_tbl[ie_num - 1].pkey), - ie_key_len); - - img->key_len = ie_key_len; + ret = read_validate_ie_tbl(img); + if (ret != 0) + return ret; key_found = 1; } #endif if (key_found == 0) { - /* check key length */ - if (!((hdr->key_len == 2 * KEY_SIZE_BYTES / 4) || - (hdr->key_len == 2 * KEY_SIZE_BYTES / 2) || - (hdr->key_len == 2 * KEY_SIZE_BYTES))) - return ERROR_ESBC_CLIENT_HEADER_KEY_LEN; - - memcpy(&img->img_key, esbc + hdr->pkey, hdr->key_len); - - img->key_len = hdr->key_len; - + ret = read_validate_single_key(img); + if (ret != 0) + return ret; key_found = 1; } -- cgit v1.2.1