OPENSSL-RSAUTL(1ssl) OpenSSL OPENSSL-RSAUTL(1ssl) openssl-rsautl - RSA openssl rsautl [-help] [-in ] [-passin ] [-rev] [-out ] [-inkey _|uri] [-keyform DER|PEM|P12|ENGINE] [-pubin] [-certin] [-sign] [-verify] [-encrypt] [-decrypt] [-pkcs] [-x931] [-oaep] [-raw] [-hexdump] [-asn1parse] [-engine ] [-rand ] [-writerand ] [-provider ] [-provider-path ] [-provparam [:]=] [-propquery _] . openssl-pkeyutl(1) . RSA. -help . -in _ . -passin . openssl-passphrase-options(1). -rev . -out _ . -inkey _|_ RSA . -keyform DER|PEM|P12|ENGINE . openssl-format-options(1) . -pubin . . . -certin RSA . -sign . RSA . -verify . -encrypt RSA . -decrypt RSA . -pkcs, -oaep, -x931, -raw : PKCS#1 v1.5 () PKCS#1 OAEP ANSI X9.31 . -pkcs -raw . : Bleichenbacher PKCS#1 v1.5 . -raw . -hexdump . -asn1parse ASN.1 -verify. -engine id " " openssl(1). . -rand -writerand " " openssl(1) . -provider -provider-path -provparam [:]= -propquery propq " " openssl(1) provider(7) property(7). RSA . openssl-pkeyutl(1). : openssl rsautl -sign -in -inkey key.pem -out openssl rsautl -verify -in -inkey key.pem : openssl rsautl -verify -in -inkey key.pem -raw -hexdump 0000 - 00 01 ff ff ff ff ff ff-ff ff ff ff ff ff ff ff ................ 0010 - ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff ................ 0020 - ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff ................ 0030 - ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff ................ 0040 - ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff ................ 0050 - ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff ................ 0060 - ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff ................ 0070 - ff ff ff ff 00 68 65 6c-6c 6f 20 77 6f 72 6c 64 .....hello world PKCS#1 . 2 ( ) 0xff. openssl-asn1parse(1). certs/pca-cert.pem. openssl-asn1parse(1) : openssl asn1parse -in pca-cert.pem 0:d=0 hl=4 l= 742 cons: SEQUENCE 4:d=1 hl=4 l= 591 cons: SEQUENCE 8:d=2 hl=2 l= 3 cons: cont [ 0 ] 10:d=3 hl=2 l= 1 prim: INTEGER :02 13:d=2 hl=2 l= 1 prim: INTEGER :00 16:d=2 hl=2 l= 13 cons: SEQUENCE 18:d=3 hl=2 l= 9 prim: OBJECT :md5WithRSAEncryption 29:d=3 hl=2 l= 0 prim: NULL 31:d=2 hl=2 l= 92 cons: SEQUENCE 33:d=3 hl=2 l= 11 cons: SET 35:d=4 hl=2 l= 9 cons: SEQUENCE 37:d=5 hl=2 l= 3 prim: OBJECT :countryName 42:d=5 hl=2 l= 2 prim: PRINTABLESTRING :AU .... 599:d=1 hl=2 l= 13 cons: SEQUENCE 601:d=2 hl=2 l= 9 prim: OBJECT :md5WithRSAEncryption 612:d=2 hl=2 l= 0 prim: NULL 614:d=1 hl=3 l= 129 prim: BIT STRING BIT STRING . : openssl asn1parse -in pca-cert.pem -out sig -noout -strparse 614 : openssl x509 -in test/testx509.pem -pubkey -noout >pubkey.pem : openssl rsautl -in sig -verify -asn1parse -inkey pubkey.pem -pubin 0:d=0 hl=2 l= 32 cons: SEQUENCE 2:d=1 hl=2 l= 12 cons: SEQUENCE 4:d=2 hl=2 l= 8 prim: OBJECT :md5 14:d=2 hl=2 l= 0 prim: NULL 16:d=1 hl=2 l= 16 prim: OCTET STRING 0000 - f3 46 9e aa 1a 4a 73 c9-37 ea 93 00 48 25 08 b5 .F...Js.7...H%.. ASN1 DigestInfo. md5. : openssl asn1parse -in pca-cert.pem -out tbs -noout -strparse 4 : openssl md5 -c tbs MD5(tbs)= f3:46:9e:aa:1a:4a:73:c9:37:ea:93:00:48:25:08:b5 . openssl(1), openssl-pkeyutl(1), openssl-dgst(1), openssl-rsa(1), openssl-genrsa(1) OpenSSL 3.0. -engine OpenSSL 3.0. 2000-2023 OpenSSL. . Apache 2.0 ( ""). . LICENSE . 3 . . : . 3.6.2 7 2026 OPENSSL-RSAUTL(1ssl)