safer

A consistent interface to encrypt/decrypt strings, objects, files and connections in R.

• symmetric and asymmetric encryption methods are supported.
• Based on libsodium crypto library.

Design

There are four functions and their inverses.

• encryt_string (decrypt_string)
• encryt_object (decrypt_object)
• encryt_file (decrypt_file)
• save_object (retrieve_object)

The following table summarizes their functionality:

Function	Input	Output	Has side-effect
`encryt_string`	a string	string/raw	No
`encryt_object`	a R object	raw/string	No
`encrypt_file`	a file on disk	TRUE	Yes (Output to disk)
`save_object`	a R object	TRUE	Yes (Output to disk)

Examples

library("safer")

String

# symmetric case:
temp <- encrypt_string("hello, how are you", key = "secret")
all(
  is.character(temp)
  , decrypt_string(temp, "secret") == "hello, how are you"
  , class(try(decrypt_string(temp, "nopass"), silent = TRUE)) == "try-error"
  )

## [1] TRUE

res <- encrypt_string("tatvamasi", ascii = FALSE)
isTRUE(identical(decrypt_string(res), "tatvamasi"))

## [1] TRUE

# asymmetric case:
alice <- keypair()
bob   <- keypair()
temp  <- encrypt_string("hello asymmetric", alice$private_key, bob$public_key)
temp2 <- decrypt_string(temp, bob$private_key, alice$public_key)
identical("hello asymmetric", temp2)

## [1] TRUE

Henceforth, we shall default password for symmetric case: pass.

Object

# symmetric case:
temp <- encrypt_object(1:3)
all(
  is.raw(temp)
  , decrypt_object(temp) == 1:3)

## [1] TRUE

temp <- encrypt_object(iris, ascii = TRUE)
all(
  is.character(temp)
  , decrypt_object(temp) == iris
  , identical(decrypt_object(temp), iris))

## [1] TRUE

rm(temp)

# asymmetric case:
alice <- keypair()
bob   <- keypair()
temp  <- encrypt_object(1:10, alice$private_key, bob$public_key)
temp2 <- decrypt_object(temp, bob$private_key, alice$public_key)
identical(1:10, temp2)

## [1] TRUE

File

# symmetric case:
write.table(iris, "iris.csv")
all(
  encrypt_file("iris.csv", outfile = "iris_encrypted.bin")
  , file.exists("iris_encrypted.bin")
  , decrypt_file("iris_encrypted.bin", outfile = "iris_2.csv")
  , file.exists("iris_2.csv")
  , tools::md5sum("iris_2.csv") == tools::md5sum("iris.csv")
  , unlink("iris.csv") == 0
  , unlink("iris_2.csv") == 0
  , unlink("iris_encrypted.bin") == 0
)

## [1] TRUE

write.table(iris, "iris.csv")
all(
  encrypt_file("iris.csv", outfile = "iris_encrypted.txt", ascii = TRUE)
  , file.exists("iris_encrypted.txt")
  , decrypt_file("iris_encrypted.txt", outfile = "iris_2.csv", ascii = TRUE)
  , file.exists("iris_2.csv")
  , tools::md5sum("iris_2.csv") == tools::md5sum("iris.csv")
  , unlink("iris.csv") == 0
  , unlink("iris_2.csv") == 0
  , unlink("iris_encrypted.txt") == 0
)

## [1] TRUE

# asymmetric case:
alice <- keypair()
bob   <- keypair()
write.table(iris, "iris.csv")
all(
  encrypt_file("iris.csv", alice$private_key, bob$public_key, outfile = "iris_encrypted.bin")
  , file.exists("iris_encrypted.bin")
  , decrypt_file("iris_encrypted.bin", bob$private_key, alice$public_key, outfile = "iris_2.csv")
  , file.exists("iris_2.csv")
  , tools::md5sum("iris_2.csv") == tools::md5sum("iris.csv")
  , unlink("iris.csv") == 0
  , unlink("iris_2.csv") == 0
  , unlink("iris_encrypted.bin") == 0
)

## [1] TRUE

Save

# symmetric case:
all(
  save_object(iris, conn = "iris_safer.bin")
  , identical(retrieve_object(conn = "iris_safer.bin"), iris)
  , unlink("iris_safer.bin") == 0
)

## [1] TRUE

all(
  save_object(iris, conn = "iris_safer_2.txt", ascii = TRUE)
  , identical(retrieve_object(conn = "iris_safer_2.txt", ascii = TRUE), iris)
  , unlink("iris_safer_2.txt") == 0
)

## [1] TRUE

# asymmetric case:
alice <- keypair()
bob   <- keypair()
all(
  save_object(iris, alice$private_key, bob$public_key, conn = "iris_safer.bin")
  , identical(retrieve_object(conn = "iris_safer.bin", bob$private_key, alice$public_key), iris)
  , unlink("iris_safer.bin") == 0
)

## [1] TRUE