These files been produced with KeyTool using commands from V3 Float/Bridge setup here:
https://docs.corda.r3.com/bridge-configuration-file.html#complete-example

More specifically the following been executed on Windows:
// Trust Root with EC algo
keytool.exe -genkeypair -keyalg EC -keysize 256 -alias floatroot -validity 1000 -dname "CN=Float Root,O=Local Only,L=London,C=GB" -ext bc:ca:true,pathlen:1 -keystore floatca.jks -storepass capass -keypass cakeypass

// Bridge and Float with EC
keytool.exe -genkeypair -keyalg EC -keysize 256 -alias bridgecert -validity 1000 -dname "CN=Bridge Local,O=Local Only,L=London,C=GB" -ext bc:ca:false -keystore bridge_ec.jks -storepass bridgepass -keypass bridgepass
keytool.exe -genkeypair -keyalg EC -keysize 256 -alias floatcert -validity 1000 -dname "CN=Float Local,O=Local Only,L=London,C=GB" -ext bc:ca:false -keystore float_ec.jks -storepass floatpass -keypass floatpass

// Bridge and Float with RSA
keytool.exe -genkeypair -keyalg RSA -keysize 1024 -alias bridgecert -validity 1000 -dname "CN=Bridge Local,O=Local Only,L=London,C=GB" -ext bc:ca:false -keystore bridge_rsa.jks -storepass bridgepass -keypass bridgepass
keytool.exe -genkeypair -keyalg RSA -keysize 1024 -alias floatcert -validity 1000 -dname "CN=Float Local,O=Local Only,L=London,C=GB" -ext bc:ca:false -keystore float_rsa.jks -storepass floatpass -keypass floatpass

// Export Trust root for subsequent chaining
keytool.exe -exportcert -rfc -alias floatroot -keystore floatca.jks -storepass capass -keypass cakeypass > root.pem
keytool.exe -importcert -noprompt -file root.pem -alias root -keystore trust.jks -storepass trustpass

// Create a chain for EC Bridge
keytool.exe -certreq -alias bridgecert -keystore bridge_ec.jks -storepass bridgepass -keypass bridgepass |keytool.exe -gencert -validity 1000 -ext ku:c=dig,keyEncipherment -ext: eku:true=serverAuth,clientAuth -rfc -keystore floatca.jks -alias floatroot -storepass capass -keypass cakeypass > bridge_ec.pem
type root.pem bridge_ec.pem >> bridgechain_ec.pem
keytool.exe -importcert -noprompt -file bridgechain_ec.pem -alias bridgecert -keystore bridge_ec.jks -storepass bridgepass -keypass bridgepass

// Create a chain for RSA Bridge
keytool.exe -certreq -alias bridgecert -keystore bridge_rsa.jks -storepass bridgepass -keypass bridgepass |keytool.exe -gencert -validity 1000 -ext ku:c=dig,keyEncipherment -ext: eku:true=serverAuth,clientAuth -rfc -keystore floatca.jks -alias floatroot -storepass capass -keypass cakeypass > bridge_rsa.pem
type root.pem bridge_rsa.pem >> bridgechain_rsa.pem
keytool.exe -importcert -noprompt -file bridgechain_rsa.pem -alias bridgecert -keystore bridge_rsa.jks -storepass bridgepass -keypass bridgepass

// Create a chain for EC Float
keytool.exe -certreq -alias floatcert -keystore float_ec.jks -storepass floatpass -keypass floatpass |keytool.exe -gencert -validity 1000 -ext ku:c=dig,keyEncipherment -ext: eku::true=serverAuth,clientAuth -rfc -keystore floatca.jks -alias floatroot -storepass capass -keypass cakeypass > float_ec.pem
type root.pem float_ec.pem >> floatchain_ec.pem
keytool.exe -importcert -noprompt -file floatchain_ec.pem -alias floatcert -keystore float_ec.jks -storepass floatpass -keypass floatpass

// Create a chain for RSA Float
keytool.exe -certreq -alias floatcert -keystore float_rsa.jks -storepass floatpass -keypass floatpass |keytool.exe -gencert -validity 1000 -ext ku:c=dig,keyEncipherment -ext: eku::true=serverAuth,clientAuth -rfc -keystore floatca.jks -alias floatroot -storepass capass -keypass cakeypass > float_rsa.pem
type root.pem float_rsa.pem >> floatchain_rsa.pem
keytool.exe -importcert -noprompt -file floatchain_rsa.pem -alias floatcert -keystore float_rsa.jks -storepass floatpass -keypass floatpass