Title: | Toolkit for Encryption, Signatures and Certificates Based on OpenSSL |
---|---|
Description: | Bindings to OpenSSL libssl and libcrypto, plus custom SSH key parsers. Supports RSA, DSA and EC curves P-256, P-384, P-521, and curve25519. Cryptographic signatures can either be created and verified manually or via x509 certificates. AES can be used in cbc, ctr or gcm mode for symmetric encryption; RSA for asymmetric (public key) encryption or EC for Diffie Hellman. High-level envelope functions combine RSA and AES for encrypting arbitrary sized data. Other utilities include key generators, hash functions (md5, sha1, sha256, etc), base64 encoder, a secure random number generator, and 'bignum' math methods for manually performing crypto calculations on large multibyte integers. |
Authors: | Jeroen Ooms [aut, cre] |
Maintainer: | Jeroen Ooms <[email protected]> |
License: | MIT + file LICENSE |
Version: | 2.2.1 |
Built: | 2024-08-16 10:19:11 UTC |
Source: | https://github.com/jeroen/openssl |
Low-level symmetric encryption/decryption using the AES block cipher in CBC mode.
The key is a raw vector, for example a hash of some secret. When no shared
secret is available, a random key can be used which is exchanged via an
asymmetric protocol such as RSA. See rsa_encrypt()
for a worked example
or encrypt_envelope()
for a high-level wrapper combining AES and RSA.
aes_ctr_encrypt(data, key, iv = rand_bytes(16)) aes_ctr_decrypt(data, key, iv = attr(data, "iv")) aes_cbc_encrypt(data, key, iv = rand_bytes(16)) aes_cbc_decrypt(data, key, iv = attr(data, "iv")) aes_gcm_encrypt(data, key, iv = rand_bytes(12)) aes_gcm_decrypt(data, key, iv = attr(data, "iv")) aes_keygen(length = 16)
aes_ctr_encrypt(data, key, iv = rand_bytes(16)) aes_ctr_decrypt(data, key, iv = attr(data, "iv")) aes_cbc_encrypt(data, key, iv = rand_bytes(16)) aes_cbc_decrypt(data, key, iv = attr(data, "iv")) aes_gcm_encrypt(data, key, iv = rand_bytes(12)) aes_gcm_decrypt(data, key, iv = attr(data, "iv")) aes_keygen(length = 16)
data |
raw vector or path to file with data to encrypt or decrypt |
key |
raw vector of length 16, 24 or 32, e.g. the hash of a shared secret |
iv |
raw vector of length 16 (aes block size) or NULL. The initialization vector is not secret but should be random |
length |
how many bytes to generate. Usually 16 (128-bit) or 12 (92-bit) for |
# aes-256 requires 32 byte key passphrase <- charToRaw("This is super secret") key <- sha256(passphrase) # symmetric encryption uses same key for decryption x <- serialize(iris, NULL) y <- aes_cbc_encrypt(x, key = key) x2 <- aes_cbc_decrypt(y, key = key) stopifnot(identical(x, x2))
# aes-256 requires 32 byte key passphrase <- charToRaw("This is super secret") key <- sha256(passphrase) # symmetric encryption uses same key for decryption x <- serialize(iris, NULL) y <- aes_cbc_encrypt(x, key = key) x2 <- aes_cbc_decrypt(y, key = key) stopifnot(identical(x, x2))
Encode and decode binary data into a base64 string. Character vectors are automatically collapsed into a single string.
base64_encode(bin, linebreaks = FALSE) base64_decode(text)
base64_encode(bin, linebreaks = FALSE) base64_decode(text)
bin |
raw or character vector with data to encode into base64 |
linebreaks |
insert linebreaks in the base64 message to make it more readable |
text |
string with base64 data to decode |
input <- charToRaw("foo = bar + 5") message <- base64_encode(input) output <- base64_decode(message) identical(output, input)
input <- charToRaw("foo = bar + 5") message <- base64_encode(input) output <- base64_decode(message) identical(output, input)
Password based key derivation function with bcrypt. This is not part of openssl. It is needed to parse private key files which are encoded in the new openssh format.
bcrypt_pbkdf(password, salt, rounds = 16L, size = 32L)
bcrypt_pbkdf(password, salt, rounds = 16L, size = 32L)
password |
string or raw vector with password |
salt |
raw vector with (usually 16) bytes |
rounds |
number of hashing rounds |
size |
desired length of the output key |
Basic operations for working with large integers. The bignum
function converts a positive integer, string or raw vector into a bignum type.
All basic Arithmetic and Comparison operators such as
+
, -
, *
, ^
, %%
, %/%
, ==
,
!=
, <
, <=
, >
and >=
are implemented for
bignum objects. The
Modular exponent
(a^b %% m
) can be calculated using bignum_mod_exp()
when b
is too large for calculating a^b
directly.
bignum(x, hex = FALSE) bignum_mod_exp(a, b, m) bignum_mod_inv(a, m)
bignum(x, hex = FALSE) bignum_mod_exp(a, b, m) bignum_mod_inv(a, m)
x |
an integer, string (hex or dec) or raw vector |
hex |
set to TRUE to parse strings as hex rather than decimal notation |
a |
bignum value for |
b |
bignum value for |
m |
bignum value for |
# create a bignum x <- bignum(123L) y <- bignum("123456789123456789") z <- bignum("D41D8CD98F00B204E9800998ECF8427E", hex = TRUE) # Basic arithmetic div <- z %/% y mod <- z %% y z2 <- div * y + mod stopifnot(z2 == z) stopifnot(div < z)
# create a bignum x <- bignum(123L) y <- bignum("123456789123456789") z <- bignum("D41D8CD98F00B204E9800998ECF8427E", hex = TRUE) # Basic arithmetic div <- z %/% y mod <- z %% y z2 <- div * y + mod stopifnot(z2 == z) stopifnot(div < z)
Read, download, analyze and verify X.509 certificates.
cert_verify(cert, root = ca_bundle()) download_ssl_cert(host = "localhost", port = 443, ipv4_only = FALSE) ca_bundle()
cert_verify(cert, root = ca_bundle()) download_ssl_cert(host = "localhost", port = 443, ipv4_only = FALSE) ca_bundle()
cert |
certificate (or certificate-chain) to be verified. Must be cert or list or path. |
root |
trusted pubkey or certificate(s) e.g. CA bundle. |
host |
string: hostname of the server to connect to |
port |
string or integer: port or protocol to use, e.g: |
ipv4_only |
do not use IPv6 connections |
# Verify the r-project HTTPS cert chain <- download_ssl_cert("cran.r-project.org", 443) print(chain) cert_data <- as.list(chain[[1]]) print(cert_data$pubkey) print(cert_data$alt_names) cert_verify(chain, ca_bundle()) # Write cert in PEM format cat(write_pem(chain[[1]]))
# Verify the r-project HTTPS cert chain <- download_ssl_cert("cran.r-project.org", 443) print(chain) cert_data <- as.list(chain[[1]]) print(cert_data$pubkey) print(cert_data$alt_names) cert_verify(chain, ca_bundle()) # Write cert in PEM format cat(write_pem(chain[[1]]))
Curve25519 is a recently added low-level algorithm that can be used both for diffie-hellman (called X25519) and for signatures (called ED25519). Note that these functions are only available when building against version 1.1.1 or newer of the openssl library. The same functions are also available in the sodium R package.
read_ed25519_key(x) read_ed25519_pubkey(x) read_x25519_key(x) read_x25519_pubkey(x) ed25519_sign(data, key) ed25519_verify(data, sig, pubkey) x25519_diffie_hellman(key, pubkey)
read_ed25519_key(x) read_ed25519_pubkey(x) read_x25519_key(x) read_x25519_pubkey(x) ed25519_sign(data, key) ed25519_verify(data, sig, pubkey) x25519_diffie_hellman(key, pubkey)
x |
a 32 byte raw vector with (pub)key data |
data |
raw vector with data to sign or verify |
key |
private key as returned by |
sig |
raw vector of length 64 with signature as returned by |
pubkey |
public key as returned by |
# Generate a keypair if(openssl_config()$x25519){ key <- ed25519_keygen() pubkey <- as.list(key)$pubkey # Sign message msg <- serialize(iris, NULL) sig <- ed25519_sign(msg, key) # Verify the signature ed25519_verify(msg, sig, pubkey) # Diffie Hellman example: key1 <- x25519_keygen() key2 <- x25519_keygen() # Both parties can derive the same secret x25519_diffie_hellman(key1, key2$pubkey) x25519_diffie_hellman(key2, key1$pubkey) # Import/export sodium keys rawkey <- sodium::sig_keygen() rawpubkey <- sodium::sig_pubkey(rawkey) key <- read_ed25519_key(rawkey) pubkey <- read_ed25519_pubkey(rawpubkey) # To get the raw key data back for use in sodium as.list(key)$data as.list(pubkey)$data }
# Generate a keypair if(openssl_config()$x25519){ key <- ed25519_keygen() pubkey <- as.list(key)$pubkey # Sign message msg <- serialize(iris, NULL) sig <- ed25519_sign(msg, key) # Verify the signature ed25519_verify(msg, sig, pubkey) # Diffie Hellman example: key1 <- x25519_keygen() key2 <- x25519_keygen() # Both parties can derive the same secret x25519_diffie_hellman(key1, key2$pubkey) x25519_diffie_hellman(key2, key1$pubkey) # Import/export sodium keys rawkey <- sodium::sig_keygen() rawpubkey <- sodium::sig_pubkey(rawkey) key <- read_ed25519_key(rawkey) pubkey <- read_ed25519_pubkey(rawpubkey) # To get the raw key data back for use in sodium as.list(key)$data as.list(pubkey)$data }
Key agreement is one-step method of creating a shared secret between two peers. Both peers can independently derive the joined secret by combining his or her private key with the public key from the peer.
ec_dh(key = my_key(), peerkey, password = askpass)
ec_dh(key = my_key(), peerkey, password = askpass)
key |
your own private key |
peerkey |
the public key from your peer |
password |
passed to read_key for reading protected private keys |
Currently only Elliptic Curve Diffie Hellman (ECDH) is implemented.
https://wiki.openssl.org/index.php/EVP_Key_Agreement, https://wiki.openssl.org/index.php/Elliptic_Curve_Diffie_Hellman
## Not run: # Need two EC keypairs from the same curve alice_key <- ec_keygen("P-521") bob_key <- ec_keygen("P-521") # Derive public keys alice_pub <- as.list(alice_key)$pubkey bob_pub <- as.list(bob_key)$pubkey # Both peers can derive the (same) shared secret via each other's pubkey ec_dh(alice_key, bob_pub) ec_dh(bob_key, alice_pub) ## End(Not run)
## Not run: # Need two EC keypairs from the same curve alice_key <- ec_keygen("P-521") bob_key <- ec_keygen("P-521") # Derive public keys alice_pub <- as.list(alice_key)$pubkey bob_pub <- as.list(bob_key)$pubkey # Both peers can derive the (same) shared secret via each other's pubkey ec_dh(alice_key, bob_pub) ec_dh(bob_key, alice_pub) ## End(Not run)
An envelope
contains ciphertext along with an encrypted session key and optionally and initialization
vector. The encrypt_envelope()
generates a random IV and session-key which is
used to encrypt the data
with AES()
stream cipher. The
session key itself is encrypted using the given RSA key (see rsa_encrypt()
) and
stored or sent along with the encrypted data. Each of these outputs is required to decrypt
the data with the corresponding private key.
encrypt_envelope(data, pubkey = my_pubkey()) decrypt_envelope(data, iv, session, key = my_key(), password)
encrypt_envelope(data, pubkey = my_pubkey()) decrypt_envelope(data, iv, session, key = my_key(), password)
data |
raw data vector or file path for message to be signed.
If |
pubkey |
public key or file path. See |
iv |
16 byte raw vector returned by |
session |
raw vector with encrypted session key as returned by |
key |
private key or file path. See |
password |
string or a function to read protected keys. See |
https://wiki.openssl.org/index.php/EVP_Asymmetric_Encryption_and_Decryption_of_an_Envelope
# Requires RSA key key <- rsa_keygen() pubkey <- key$pubkey msg <- serialize(iris, NULL) # Encrypt out <- encrypt_envelope(msg, pubkey) str(out) # Decrypt orig <- decrypt_envelope(out$data, out$iv, out$session, key) stopifnot(identical(msg, orig))
# Requires RSA key key <- rsa_keygen() pubkey <- key$pubkey msg <- serialize(iris, NULL) # Encrypt out <- encrypt_envelope(msg, pubkey) str(out) # Decrypt orig <- decrypt_envelope(out$data, out$iv, out$session, key) stopifnot(identical(msg, orig))
Calculates the OpenSSH fingerprint of a public key. This value should match what you get to see when connecting with SSH to a server. Note that some other systems might use a different algorithm to derive a (different) fingerprint for the same keypair.
fingerprint(key, hashfun = sha256)
fingerprint(key, hashfun = sha256)
key |
a public or private key |
hashfun |
which hash function to use to calculate the fingerprint |
mykey <- rsa_keygen() pubkey <- as.list(mykey)$pubkey fingerprint(mykey) fingerprint(pubkey) # Some systems use other hash functions fingerprint(pubkey, sha1) fingerprint(pubkey, sha256) # Other key types fingerprint(dsa_keygen())
mykey <- rsa_keygen() pubkey <- as.list(mykey)$pubkey fingerprint(mykey) fingerprint(pubkey) # Some systems use other hash functions fingerprint(pubkey, sha1) fingerprint(pubkey, sha256) # Other key types fingerprint(dsa_keygen())
All hash functions either calculate a hash-digest for key == NULL
or HMAC
(hashed message authentication code) when key
is not NULL
. Supported
inputs are binary (raw vector), strings (character vector) or a connection object.
sha1(x, key = NULL) sha224(x, key = NULL) sha256(x, key = NULL) sha384(x, key = NULL) sha512(x, key = NULL) keccak(x, size = 256, key = NULL) sha2(x, size = 256, key = NULL) sha3(x, size = 256, key = NULL) md4(x, key = NULL) md5(x, key = NULL) blake2b(x, key = NULL) blake2s(x, key = NULL) ripemd160(x, key = NULL) multihash(x, algos = c("md5", "sha1", "sha256", "sha384", "sha512"))
sha1(x, key = NULL) sha224(x, key = NULL) sha256(x, key = NULL) sha384(x, key = NULL) sha512(x, key = NULL) keccak(x, size = 256, key = NULL) sha2(x, size = 256, key = NULL) sha3(x, size = 256, key = NULL) md4(x, key = NULL) md5(x, key = NULL) blake2b(x, key = NULL) blake2s(x, key = NULL) ripemd160(x, key = NULL) multihash(x, algos = c("md5", "sha1", "sha256", "sha384", "sha512"))
x |
character vector, raw vector or connection object. |
key |
string or raw vector used as the key for HMAC hashing |
size |
must be equal to 224 256 384 or 512 |
algos |
string vector with names of hashing algorithms |
The most efficient way to calculate hashes is by using input connections, such as a file() or url() object. In this case the hash is calculated streamingly, using almost no memory or disk space, regardless of the data size. When using a connection input in the multihash function, the data is only read only once while streaming to multiple hash functions simultaneously. Therefore several hashes are calculated simultanously, without the need to store any data or download it multiple times.
Functions are vectorized for the case of character vectors: a vector with n
strings returns n
hashes. When passing a connection object, the contents will
be stream-hashed which minimizes the amount of required memory. This is recommended
for hashing files from disk or network.
The sha2 family of algorithms (sha224, sha256, sha384 and sha512) is generally recommended for sensitive information. While sha1 and md5 are usually sufficient for collision-resistant identifiers, they are no longer considered secure for cryptographic purposes.
In applications where hashes should be irreversible (such as names or passwords) it is often recommended to use a random key for HMAC hashing. This prevents attacks where we can lookup hashes of common and/or short strings. See examples. A common special case is adding a random salt to a large number of records to test for uniqueness within the dataset, while simultaneously rendering the results incomparable to other datasets.
The blake2b
and blake2s
algorithms are only available if your system has
libssl 1.1 or newer.
Digest types: https://docs.openssl.org/1.1.1/man1/dgst/
# Support both strings and binary md5(c("foo", "bar")) md5("foo", key = "secret") hash <- md5(charToRaw("foo")) as.character(hash, sep = ":") # Compare to digest digest::digest("foo", "md5", serialize = FALSE) # Other way around digest::digest(cars, skip = 0) md5(serialize(cars, NULL)) # Stream-verify from connections (including files) myfile <- system.file("CITATION") md5(file(myfile)) md5(file(myfile), key = "secret") ## Not run: check md5 from: http://cran.r-project.org/bin/windows/base/old/3.1.1/md5sum.txt md5(url("http://cran.r-project.org/bin/windows/base/old/3.1.1/R-3.1.1-win.exe")) ## End(Not run) # Use a salt to prevent dictionary attacks sha1("admin") # googleable sha1("admin", key = "random_salt_value") #not googleable # Use a random salt to identify duplicates while anonymizing values sha256("john") # googleable sha256(c("john", "mary", "john"), key = "random_salt_value")
# Support both strings and binary md5(c("foo", "bar")) md5("foo", key = "secret") hash <- md5(charToRaw("foo")) as.character(hash, sep = ":") # Compare to digest digest::digest("foo", "md5", serialize = FALSE) # Other way around digest::digest(cars, skip = 0) md5(serialize(cars, NULL)) # Stream-verify from connections (including files) myfile <- system.file("CITATION") md5(file(myfile)) md5(file(myfile), key = "secret") ## Not run: check md5 from: http://cran.r-project.org/bin/windows/base/old/3.1.1/md5sum.txt md5(url("http://cran.r-project.org/bin/windows/base/old/3.1.1/R-3.1.1-win.exe")) ## End(Not run) # Use a salt to prevent dictionary attacks sha1("admin") # googleable sha1("admin", key = "random_salt_value") #not googleable # Use a random salt to identify duplicates while anonymizing values sha256("john") # googleable sha256(c("john", "mary", "john"), key = "random_salt_value")
The keygen
functions generate a random private key. Use as.list(key)$pubkey
to derive the corresponding public key. Use write_pem to save a private key
to a file, optionally with a password.
rsa_keygen(bits = 2048) dsa_keygen(bits = 1024) ec_keygen(curve = c("P-256", "P-384", "P-521")) x25519_keygen() ed25519_keygen()
rsa_keygen(bits = 2048) dsa_keygen(bits = 1024) ec_keygen(curve = c("P-256", "P-384", "P-521")) x25519_keygen() ed25519_keygen()
bits |
bitsize of the generated RSA/DSA key |
curve |
which NIST curve to use |
# Generate keypair key <- rsa_keygen() pubkey <- as.list(key)$pubkey # Write/read the key with a passphrase write_pem(key, "id_rsa", password = "supersecret") read_key("id_rsa", password = "supersecret") unlink("id_rsa")
# Generate keypair key <- rsa_keygen() pubkey <- as.list(key)$pubkey # Write/read the key with a passphrase write_pem(key, "id_rsa", password = "supersecret") read_key("id_rsa", password = "supersecret") unlink("id_rsa")
The default user key can be set in the USER_KEY
variable and otherwise
is ~/.ssh/id_rsa
. Note that on Windows we treat ~
as the windows user
home (and not the documents folder).
my_key() my_pubkey()
my_key() my_pubkey()
The my_pubkey()
function looks for the public key by appending .pub
to the above key path. If this file does not exist, it reads the private key file
and automatically derives the corresponding pubkey. In the latter case the user
may be prompted for a passphrase if the private key is protected.
# Set random RSA key as default key <- rsa_keygen() write_pem(key, tmp <- tempfile(), password = "") rm(key) Sys.setenv("USER_KEY" = tmp) # Check the new keys print(my_key()) print(my_pubkey())
# Set random RSA key as default key <- rsa_keygen() write_pem(key, tmp <- tempfile(), password = "") rm(key) Sys.setenv("USER_KEY" = tmp) # Check the new keys print(my_key()) print(my_pubkey())
Bindings to OpenSSL libssl and libcrypto, plus custom SSH pubkey
parsers. Supports RSA, DSA and NIST curves P-256, P-384 and P-521. Cryptographic
signatures can either be created and verified
manually or via x509 certificates. The
AES block cipher is used in CBC mode for symmetric
encryption; RSA for asymmetric (public key)
encryption. High-level envelope methods
combine RSA and AES for encrypting arbitrary sized data. Other utilities include
key generators, hash functions (md5()
,
sha1()
, sha256()
, etc),
base64()
encoder, a secure random number generator,
and bignum()
math methods for manually performing crypto
calculations on large multibyte integers.
Jeroen Ooms, Oliver Keyes
Useful links:
Shows libssl version and configuration information.
openssl_config() fips_mode()
openssl_config() fips_mode()
Note that the "fips" flag in openssl_config
means that FIPS is
supported, but it does not mean that it is currently enforced. If
supported, it can be enabled in several ways, such as a kernel
option, or setting an environment variable OPENSSL_FORCE_FIPS_MODE=1
.
The fips_mode()
function shows if FIPS is currently enforced.
Encrypt or decrypt messages using PKCS7 smime format. Note PKCS7 only supports RSA keys.
pkcs7_encrypt(message, cert, pem = TRUE) pkcs7_decrypt(input, key, der = is.raw(input))
pkcs7_encrypt(message, cert, pem = TRUE) pkcs7_decrypt(input, key, der = is.raw(input))
message |
text or raw vector with data to encrypt |
cert |
the certificate with public key to use for encryption |
pem |
convert output pkcs7 data to PEM format |
input |
file path or string with PEM or raw vector with p7b data |
key |
private key to decrypt data |
der |
assume input is in DER format (rather than PEM) |
this set of functions generates random bytes or numbers from OpenSSL. This
provides a cryptographically secure alternative to R's default random number generator.
rand_bytes
generates n
random cryptographically secure bytes
rand_bytes(n = 1) rand_num(n = 1)
rand_bytes(n = 1) rand_num(n = 1)
n |
number of random bytes or numbers to generate |
OpenSSL manual: https://docs.openssl.org/1.1.1/man3/RAND_bytes/
rnd <- rand_bytes(10) as.numeric(rnd) as.character(rnd) as.logical(rawToBits(rnd)) # bytes range from 0 to 255 rnd <- rand_bytes(100000) hist(as.numeric(rnd), breaks=-1:255) # Generate random doubles between 0 and 1 rand_num(5) # Use CDF to map [0,1] into random draws from a distribution x <- qnorm(rand_num(1000), mean=100, sd=15) hist(x) y <- qbinom(rand_num(1000), size=10, prob=0.3) hist(y)
rnd <- rand_bytes(10) as.numeric(rnd) as.character(rnd) as.logical(rawToBits(rnd)) # bytes range from 0 to 255 rnd <- rand_bytes(100000) hist(as.numeric(rnd), breaks=-1:255) # Generate random doubles between 0 and 1 rand_num(5) # Use CDF to map [0,1] into random draws from a distribution x <- qnorm(rand_num(1000), mean=100, sd=15) hist(x) y <- qbinom(rand_num(1000), size=10, prob=0.3) hist(y)
The read_key
function (private keys) and read_pubkey
(public keys)
support both SSH pubkey format and OpenSSL PEM format (base64 data with a --BEGIN
and ---END
header), and automatically convert where necessary. The functions assume
a single key per file except for read_cert_bundle
which supports PEM files
with multiple certificates.
read_key(file, password = askpass, der = is.raw(file)) read_pubkey(file, der = is.raw(file)) read_cert(file, der = is.raw(file)) read_cert_bundle(file) read_pem(file)
read_key(file, password = askpass, der = is.raw(file)) read_pubkey(file, der = is.raw(file)) read_cert(file, der = is.raw(file)) read_cert_bundle(file) read_pem(file)
file |
Either a path to a file, a connection, or literal data (a string for pem/ssh format, or a raw vector in der format) |
password |
A string or callback function to read protected keys |
der |
set to |
Most versions of OpenSSL support at least RSA, DSA and ECDSA keys. Certificates must conform to the X509 standard.
The password
argument is needed when reading keys that are protected with a
passphrase. It can either be a string containing the passphrase, or a custom callback
function that will be called by OpenSSL to read the passphrase. The function should
take one argument (a string with a message) and return a string. The default is to
use readline
which will prompt the user in an interactive R session.
An object of class cert
, key
or pubkey
which holds the data
in binary DER format and can be decomposed using as.list
.
## Not run: # Read private key key <- read_key("~/.ssh/id_rsa") str(key) # Read public key pubkey <- read_pubkey("~/.ssh/id_rsa.pub") str(pubkey) # Read certificates txt <- readLines("https://curl.haxx.se/ca/cacert.pem") bundle <- read_cert_bundle(txt) print(bundle) ## End(Not run)
## Not run: # Read private key key <- read_key("~/.ssh/id_rsa") str(key) # Read public key pubkey <- read_pubkey("~/.ssh/id_rsa.pub") str(pubkey) # Read certificates txt <- readLines("https://curl.haxx.se/ca/cacert.pem") bundle <- read_cert_bundle(txt) print(bundle) ## End(Not run)
Asymmetric encryption and decryption with RSA. Because RSA can only encrypt messages smaller than the size of the key, it is typically used only for exchanging a random session-key. This session key is used to encipher arbitrary sized data via a stream cipher such as aes_cbc. See encrypt_envelope or pkcs7_encrypt for a high-level wrappers combining RSA and AES in this way.
rsa_encrypt(data, pubkey = my_pubkey(), oaep = FALSE) rsa_decrypt(data, key = my_key(), password = askpass, oaep = FALSE)
rsa_encrypt(data, pubkey = my_pubkey(), oaep = FALSE) rsa_decrypt(data, key = my_key(), password = askpass, oaep = FALSE)
data |
raw vector of max 245 bytes (for 2048 bit keys) with data to encrypt/decrypt |
pubkey |
public key or file path. See |
oaep |
if TRUE, changes padding to EME-OAEP as defined in PKCS #1 v2.0 |
key |
private key or file path. See |
password |
string or a function to read protected keys. See |
# Generate test keys key <- rsa_keygen() pubkey <- key$pubkey # Encrypt data with AES tempkey <- rand_bytes(32) iv <- rand_bytes(16) blob <- aes_cbc_encrypt(system.file("CITATION"), tempkey, iv = iv) # Encrypt tempkey using receivers public RSA key ciphertext <- rsa_encrypt(tempkey, pubkey) # Receiver decrypts tempkey from private RSA key tempkey <- rsa_decrypt(ciphertext, key) message <- aes_cbc_decrypt(blob, tempkey, iv) out <- rawToChar(message)
# Generate test keys key <- rsa_keygen() pubkey <- key$pubkey # Encrypt data with AES tempkey <- rand_bytes(32) iv <- rand_bytes(16) blob <- aes_cbc_encrypt(system.file("CITATION"), tempkey, iv = iv) # Encrypt tempkey using receivers public RSA key ciphertext <- rsa_encrypt(tempkey, pubkey) # Receiver decrypts tempkey from private RSA key tempkey <- rsa_decrypt(ciphertext, key) message <- aes_cbc_decrypt(blob, tempkey, iv) out <- rawToChar(message)
Sign and verify a message digest. RSA supports both MD5 and SHA signatures
whereas DSA and EC keys only support SHA. ED25591 can sign any payload so you can
set hash
to NULL
to sign the raw input data.
signature_create(data, hash = sha1, key = my_key(), password = askpass) signature_verify(data, sig, hash = sha1, pubkey = my_pubkey()) ecdsa_parse(sig) ecdsa_write(r, s)
signature_create(data, hash = sha1, key = my_key(), password = askpass) signature_verify(data, sig, hash = sha1, pubkey = my_pubkey()) ecdsa_parse(sig) ecdsa_write(r, s)
data |
raw data vector or file path for message to be signed.
If |
hash |
the digest function to use. Must be one of |
key |
private key or file path. See |
password |
string or a function to read protected keys. See |
sig |
raw vector or file path for the signature data. |
pubkey |
public key or file path. See |
r |
bignum value for r parameter |
s |
bignum value for s parameter |
The ecdsa_parse
and ecdsa_write
functions convert (EC)DSA signatures
between the conventional DER format and the raw (r,s)
bignum pair. Most
users won't need this, it is mostly here to support the JWT format (which does not
use DER).
# Generate a keypair key <- rsa_keygen() pubkey <- key$pubkey # Sign a file data <- system.file("DESCRIPTION") sig <- signature_create(data, sha256, key = key) stopifnot(signature_verify(data, sig, sha256, pubkey = pubkey)) # Sign raw data data <- serialize(iris, NULL) sig <- signature_create(data, sha256, key = key) stopifnot(signature_verify(data, sig, sha256, pubkey = pubkey)) # Sign a hash md <- md5(data) sig <- signature_create(md, hash = sha256, key = key) stopifnot(signature_verify(md, sig, hash = sha256, pubkey = pubkey)) # # ECDSA example data <- serialize(iris, NULL) key <- ec_keygen() pubkey <- key$pubkey sig <- signature_create(data, sha256, key = key) stopifnot(signature_verify(data, sig, sha256, pubkey = pubkey)) # Convert signature to (r, s) parameters and then back params <- ecdsa_parse(sig) out <- ecdsa_write(params$r, params$s) identical(sig, out)
# Generate a keypair key <- rsa_keygen() pubkey <- key$pubkey # Sign a file data <- system.file("DESCRIPTION") sig <- signature_create(data, sha256, key = key) stopifnot(signature_verify(data, sig, sha256, pubkey = pubkey)) # Sign raw data data <- serialize(iris, NULL) sig <- signature_create(data, sha256, key = key) stopifnot(signature_verify(data, sig, sha256, pubkey = pubkey)) # Sign a hash md <- md5(data) sig <- signature_create(md, hash = sha256, key = key) stopifnot(signature_verify(md, sig, hash = sha256, pubkey = pubkey)) # # ECDSA example data <- serialize(iris, NULL) key <- ec_keygen() pubkey <- key$pubkey sig <- signature_create(data, sha256, key = key) stopifnot(signature_verify(data, sig, sha256, pubkey = pubkey)) # Convert signature to (r, s) parameters and then back params <- ecdsa_parse(sig) out <- ecdsa_write(params$r, params$s) identical(sig, out)
These functions allow for manipulating the SSL context from inside the
CURLOPT_SSL_CTX_FUNCTION
callback using the curl R package. Note that this is not fully portable and will
only work on installations that use matching versions of libssl (see details).
It is recommended to only use this locally and if what you need cannot be
accomplished using standard libcurl TLS options, e.g. those listed in
curl::curl_options('ssl')
or curl::curl_options('tls')
.
ssl_ctx_add_cert_to_store(ssl_ctx, cert) ssl_ctx_set_verify_callback(ssl_ctx, cb) ssl_ctx_curl_version_match()
ssl_ctx_add_cert_to_store(ssl_ctx, cert) ssl_ctx_set_verify_callback(ssl_ctx, cb) ssl_ctx_curl_version_match()
ssl_ctx |
pointer object to the SSL context provided in the ssl_ctx_function callback. |
cert |
certificate object, e.g from read_cert or download_ssl_cert. |
cb |
callback function with 1 parameter (the server certificate) and which returns TRUE (for proceed) or FALSE (for abort). |
Curl allows for setting an option called ssl_ctx_function
:
this is a callback function that is triggered during the TLS initiation, before
any https connection has been made. This serves as a hook to let you manipulate
the TLS configuration (called SSL_CTX
for historical reasons), in order to
control how to curl will validate the authenticity of server certificates for
upcoming TLS connections.
Currently we provide 2 such functions: ssl_ctx_add_cert_to_store injects a
custom certificate into the trust-store of the current TLS connection. But
most flexibility is provided via ssl_ctx_set_verify_callback which allows
you to override the function that is used by validate if a server certificate
should be trusted. The callback will receive one argument cert
and has to
return TRUE
or FALSE
to decide if the cert should be trusted.
By default libcurl re-uses connections, hence the cert validation is only
performed in the first request to a given host. Subsequent requests use the
already established TLS connection. For testing, it can be useful to set
forbid_reuse
in order to make a new connection for each request, as done
in the examples below.
Passing the SSL_CTX between the curl and openssl R packages only works if they
are linked to the same version of libssl. Use ssl_ctx_curl_version_match
to test if this is the case. On Debian / Ubuntu you need to build the R curl
package against libcurl4-openssl-dev
, which is usually the case. On Windows
you would need to set CURL_SSL_BACKEND=openssl
in your ~/.Renviron
file.
On MacOS things are complicated because it uses LibreSSL instead of OpenSSL
by default. You can make it work by compiling the curl R package from source
against the homebrew version of curl and then then set CURL_SSL_BACKEND=openssl
in your ~/.Renviron
file. If your curl and openssl R packages use different
versions of libssl, the examples may segfault due to ABI incompatibility of the
SSL_CTX structure.
## Not run: # Example 1: accept your local snakeoil https cert mycert <- openssl::download_ssl_cert('localhost')[[1]] # Setup the callback h <- curl::new_handle(ssl_ctx_function = function(ssl_ctx){ ssl_ctx_add_cert_to_store(ssl_ctx, mycert) }, verbose = TRUE, forbid_reuse = TRUE) # Perform the request req <- curl::curl_fetch_memory('https://localhost', handle = h) # Example 2 using a custom verify function verify_cb <- function(cert){ id <- cert$pubkey$fingerprint cat("Server cert from:", as.character(id), "\n") TRUE # always accept cert } h <- curl::new_handle(ssl_ctx_function = function(ssl_ctx){ ssl_ctx_set_verify_callback(ssl_ctx, verify_cb) }, verbose = TRUE, forbid_reuse = TRUE) # Perform the request req <- curl::curl_fetch_memory('https://localhost', handle = h) ## End(Not run)
## Not run: # Example 1: accept your local snakeoil https cert mycert <- openssl::download_ssl_cert('localhost')[[1]] # Setup the callback h <- curl::new_handle(ssl_ctx_function = function(ssl_ctx){ ssl_ctx_add_cert_to_store(ssl_ctx, mycert) }, verbose = TRUE, forbid_reuse = TRUE) # Perform the request req <- curl::curl_fetch_memory('https://localhost', handle = h) # Example 2 using a custom verify function verify_cb <- function(cert){ id <- cert$pubkey$fingerprint cat("Server cert from:", as.character(id), "\n") TRUE # always accept cert } h <- curl::new_handle(ssl_ctx_function = function(ssl_ctx){ ssl_ctx_set_verify_callback(ssl_ctx, verify_cb) }, verbose = TRUE, forbid_reuse = TRUE) # Perform the request req <- curl::curl_fetch_memory('https://localhost', handle = h) ## End(Not run)
PKCS7 and PKCS12 are container formats for storing multiple certificates and/or keys.
write_p12( key = NULL, cert = NULL, ca = NULL, name = NULL, password = NULL, path = NULL ) write_p7b(ca, path = NULL) read_p12(file, password = askpass) read_p7b(file, der = is.raw(file))
write_p12( key = NULL, cert = NULL, ca = NULL, name = NULL, password = NULL, path = NULL ) write_p7b(ca, path = NULL) read_p12(file, password = askpass) read_p7b(file, der = is.raw(file))
key |
a private key |
cert |
certificate that matches |
ca |
a list of certificates (the CA chain) |
name |
a friendly title for the bundle |
password |
string or function to set/get the password. |
path |
a file where to write the output to. If |
file |
path or raw vector with binary PKCS12 data to parse |
der |
set to TRUE for binary files and FALSE for PEM files |
The PKCS#7 or P7B format is a container for one or more certificates. It can either be stored in binary form or in a PEM file. P7B files are typically used to import and export public certificates.
The PKCS#12 or PFX format is a binary-only format for storing the server certificate, any intermediate certificates, and the private key into a single encryptable file. PFX files are usually found with the extensions .pfx and .p12. PFX files are typically used to import and export certificates with their private keys.
The PKCS formats also allow for including signatures and CRLs but this is quite rare and these are currently ignored.
The write_pem
functions exports a key or certificate to the standard
base64 PEM format. For private keys it is possible to set a password.
write_pem(x, path = NULL, password = NULL) write_der(x, path = NULL) write_pkcs1(x, path = NULL, password = NULL) write_ssh(pubkey, path = NULL) write_openssh_pem(key, path = NULL)
write_pem(x, path = NULL, password = NULL) write_der(x, path = NULL) write_pkcs1(x, path = NULL, password = NULL) write_ssh(pubkey, path = NULL) write_openssh_pem(key, path = NULL)
x |
a public/private key or certificate object |
path |
file to write to. If |
password |
string or callback function to set password (only applicable for private keys). |
pubkey |
a public key |
key |
a private key |
The pkcs1 format is the old legacy format used by OpenSSH. PKCS1 does not
support the new ed25519 keys, for which you need write_openssh_pem
.
For non-ssh clients, we recommend to simply use write_pem
to export keys
and certs into the recommended formats.
# Generate RSA keypair key <- rsa_keygen() pubkey <- key$pubkey # Write to output formats write_ssh(pubkey) write_pem(pubkey) write_pem(key, password = "super secret")
# Generate RSA keypair key <- rsa_keygen() pubkey <- key$pubkey # Write to output formats write_ssh(pubkey) write_pem(pubkey) write_pem(key, password = "super secret")