/* SPDX-License-Identifier: GPL-2.0-only */

  /*
   * Copyright (C) 2009-2010 IBM Corporation
   *
   * Authors:
   * Mimi Zohar <zohar@us.ibm.com>

   */

  #ifdef pr_fmt
  #undef pr_fmt
  #endif
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

  #include <linux/types.h>
  #include <linux/integrity.h>
  #include <crypto/sha.h>

  #include <linux/key.h>

  #include <linux/audit.h>

  /* iint action cache flags */

  #define IMA_MEASURE		0x00000001
  #define IMA_MEASURED		0x00000002
  #define IMA_APPRAISE		0x00000004
  #define IMA_APPRAISED		0x00000008
  /*#define IMA_COLLECT		0x00000010  do not use this flag */
  #define IMA_COLLECTED		0x00000020
  #define IMA_AUDIT		0x00000040
  #define IMA_AUDITED		0x00000080

  #define IMA_HASH		0x00000100
  #define IMA_HASHED		0x00000200

  /* iint cache flags */

  #define IMA_ACTION_FLAGS	0xff000000

  #define IMA_DIGSIG_REQUIRED	0x01000000
  #define IMA_PERMIT_DIRECTIO	0x02000000
  #define IMA_NEW_FILE		0x04000000
  #define EVM_IMMUTABLE_DIGSIG	0x08000000

  #define IMA_FAIL_UNVERIFIABLE_SIGS	0x10000000

  #define IMA_MODSIG_ALLOWED	0x20000000

  #define IMA_CHECK_BLACKLIST	0x40000000

  #define IMA_DO_MASK		(IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \

  				 IMA_HASH | IMA_APPRAISE_SUBMASK)

  #define IMA_DONE_MASK		(IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \

  				 IMA_HASHED | IMA_COLLECTED | \
  				 IMA_APPRAISED_SUBMASK)

  
  /* iint subaction appraise cache flags */

  #define IMA_FILE_APPRAISE	0x00001000
  #define IMA_FILE_APPRAISED	0x00002000
  #define IMA_MMAP_APPRAISE	0x00004000
  #define IMA_MMAP_APPRAISED	0x00008000
  #define IMA_BPRM_APPRAISE	0x00010000
  #define IMA_BPRM_APPRAISED	0x00020000
  #define IMA_READ_APPRAISE	0x00040000
  #define IMA_READ_APPRAISED	0x00080000

  #define IMA_CREDS_APPRAISE	0x00100000
  #define IMA_CREDS_APPRAISED	0x00200000

  #define IMA_APPRAISE_SUBMASK	(IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \

  				 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
  				 IMA_CREDS_APPRAISE)

  #define IMA_APPRAISED_SUBMASK	(IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \

  				 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
  				 IMA_CREDS_APPRAISED)

  /* iint cache atomic_flags */
  #define IMA_CHANGE_XATTR	0
  #define IMA_UPDATE_XATTR	1
  #define IMA_CHANGE_ATTR		2
  #define IMA_DIGSIG		3
  #define IMA_MUST_MEASURE	4

  enum evm_ima_xattr_type {
  	IMA_XATTR_DIGEST = 0x01,
  	EVM_XATTR_HMAC,
  	EVM_IMA_XATTR_DIGSIG,

  	IMA_XATTR_DIGEST_NG,

  	EVM_XATTR_PORTABLE_DIGSIG,

  	IMA_XATTR_LAST

  };
  
  struct evm_ima_xattr_data {
  	u8 type;

  	u8 data[];
  } __packed;
  
  /* Only used in the EVM HMAC code. */
  struct evm_xattr {
  	struct evm_ima_xattr_data data;

  	u8 digest[SHA1_DIGEST_SIZE];

  } __packed;
  
  #define IMA_MAX_DIGEST_SIZE	64
  
  struct ima_digest_data {
  	u8 algo;
  	u8 length;

  	union {
  		struct {
  			u8 unused;
  			u8 type;
  		} sha1;
  		struct {
  			u8 type;
  			u8 algo;
  		} ng;
  		u8 data[2];
  	} xattr;

  	u8 digest[];

  } __packed;

  /*
   * signature format v2 - for using with asymmetric keys
   */
  struct signature_v2_hdr {

  	uint8_t type;		/* xattr type */

  	uint8_t version;	/* signature format version */

  	uint8_t	hash_algo;	/* Digest algorithm [enum hash_algo] */

  	__be32 keyid;		/* IMA key identifier - not X509/PGP specific */
  	__be16 sig_size;	/* signature size */

  	uint8_t sig[];		/* signature payload */

  } __packed;

  /* integrity data associated with an inode */
  struct integrity_iint_cache {

  	struct rb_node rb_node;	/* rooted in integrity_iint_tree */

  	struct mutex mutex;	/* protects: version, flags, digest */

  	struct inode *inode;	/* back pointer to inode in question */
  	u64 version;		/* track inode changes */

  	unsigned long flags;

  	unsigned long measured_pcrs;

  	unsigned long atomic_flags;

  	enum integrity_status ima_file_status:4;
  	enum integrity_status ima_mmap_status:4;
  	enum integrity_status ima_bprm_status:4;

  	enum integrity_status ima_read_status:4;

  	enum integrity_status ima_creds_status:4;

  	enum integrity_status evm_status:4;

  	struct ima_digest_data *ima_hash;

  };
  
  /* rbtree tree calls to lookup, insert, delete
   * integrity data associated with an inode.
   */

  struct integrity_iint_cache *integrity_iint_find(struct inode *inode);

  int integrity_kernel_read(struct file *file, loff_t offset,

  			  void *addr, unsigned long count);

  #define INTEGRITY_KEYRING_EVM		0

  #define INTEGRITY_KEYRING_IMA		1

  #define INTEGRITY_KEYRING_PLATFORM	2
  #define INTEGRITY_KEYRING_MAX		3

  extern struct dentry *integrity_dir;

  struct modsig;

  #ifdef CONFIG_INTEGRITY_SIGNATURE

  
  int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,

  			    const char *digest, int digestlen);

  int integrity_modsig_verify(unsigned int id, const struct modsig *modsig);

  int __init integrity_init_keyring(const unsigned int id);

  int __init integrity_load_x509(const unsigned int id, const char *path);

  int __init integrity_load_cert(const unsigned int id, const char *source,

  			       const void *data, size_t len, key_perm_t perm);

  #else
  
  static inline int integrity_digsig_verify(const unsigned int id,
  					  const char *sig, int siglen,
  					  const char *digest, int digestlen)
  {
  	return -EOPNOTSUPP;
  }

  static inline int integrity_modsig_verify(unsigned int id,
  					  const struct modsig *modsig)
  {
  	return -EOPNOTSUPP;
  }

  static inline int integrity_init_keyring(const unsigned int id)
  {
  	return 0;
  }

  
  static inline int __init integrity_load_cert(const unsigned int id,
  					     const char *source,
  					     const void *data, size_t len,

  					     key_perm_t perm)

  {
  	return 0;
  }

  #endif /* CONFIG_INTEGRITY_SIGNATURE */

  #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
  int asymmetric_verify(struct key *keyring, const char *sig,
  		      int siglen, const char *data, int datalen);
  #else
  static inline int asymmetric_verify(struct key *keyring, const char *sig,
  				    int siglen, const char *data, int datalen)
  {
  	return -EOPNOTSUPP;
  }
  #endif

  #ifdef CONFIG_IMA_APPRAISE_MODSIG
  int ima_modsig_verify(struct key *keyring, const struct modsig *modsig);
  #else
  static inline int ima_modsig_verify(struct key *keyring,
  				    const struct modsig *modsig)
  {
  	return -EOPNOTSUPP;
  }
  #endif

  #ifdef CONFIG_IMA_LOAD_X509
  void __init ima_load_x509(void);
  #else
  static inline void ima_load_x509(void)
  {
  }
  #endif

  #ifdef CONFIG_EVM_LOAD_X509
  void __init evm_load_x509(void);
  #else
  static inline void evm_load_x509(void)
  {
  }
  #endif

  #ifdef CONFIG_INTEGRITY_AUDIT
  /* declarations */
  void integrity_audit_msg(int audit_msgno, struct inode *inode,
  			 const unsigned char *fname, const char *op,
  			 const char *cause, int result, int info);

  void integrity_audit_message(int audit_msgno, struct inode *inode,
  			     const unsigned char *fname, const char *op,
  			     const char *cause, int result, int info,
  			     int errno);

  static inline struct audit_buffer *
  integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
  {
  	return audit_log_start(ctx, gfp_mask, type);
  }

  #else
  static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
  				       const unsigned char *fname,
  				       const char *op, const char *cause,
  				       int result, int info)
  {
  }

  static inline void integrity_audit_message(int audit_msgno,
  					   struct inode *inode,
  					   const unsigned char *fname,
  					   const char *op, const char *cause,
  					   int result, int info, int errno)
  {
  }

  static inline struct audit_buffer *
  integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
  {
  	return NULL;
  }

  #endif

  
  #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
  void __init add_to_platform_keyring(const char *source, const void *data,
  				    size_t len);
  #else
  static inline void __init add_to_platform_keyring(const char *source,
  						  const void *data, size_t len)
  {
  }
  #endif