Encrypt and Decrypt Strings, R Objects and Files.

safer

A consistent interface to encrypt/decrypt strings, objects, files and connections in R. Both symmetric and asymmetric encryption methods are supported. Thanks to excellent packages sodium and base64enc.

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:

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