From: Laszlo Ersek Date: Sat, 31 Mar 2018 23:27:43 +0000 (+0200) Subject: OvmfPkg/TlsAuthConfigLib: configure trusted cipher suites for HTTPS boot X-Git-Tag: edk2-stable201903~1909 X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=commitdiff_plain;h=ba9c8a8ccbb79697509cba482f9d7b9e8526c7e2 OvmfPkg/TlsAuthConfigLib: configure trusted cipher suites for HTTPS boot Read the list of trusted cipher suites from fw_cfg and to store it to EDKII_HTTP_TLS_CIPHER_LIST_VARIABLE. The fw_cfg file will be formatted by the "update-crypto-policies" utility on the host side, so that the host settings take effect in guest HTTPS boot as well. QEMU forwards the file intact to the firmware. The contents are forwarded by NetworkPkg/HttpDxe (in TlsConfigCipherList()) to NetworkPkg/TlsDxe (TlsSetSessionData()) and TlsLib (TlsSetCipherList()). Note: the development of the "update-crypto-policies" feature is underway at this time. Meanwhile the following script can be used to generate the binary file for fw_cfg: export LC_ALL=C openssl ciphers -V \ | sed -r -n \ -e 's/^ *0x([0-9A-F]{2}),0x([0-9A-F]{2}) - .*$/\\\\x\1 \\\\x\2/p' \ | xargs -r -- printf -- '%b' > ciphers.bin Cc: Ard Biesheuvel Cc: Gary Ching-Pang Lin Cc: Jordan Justen Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Laszlo Ersek Reviewed-by: Gary Lin Tested-by: Gary Lin Reviewed-by: Long Qin Reviewed-by: Jiaxin Wu [lersek@redhat.com: update commit msg and add script as requested by Gary] [lersek@redhat.com: update commit msg as requested by Jiaxin] --- diff --git a/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.c b/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.c index b5b33bc4fc..74c393e546 100644 --- a/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.c +++ b/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.c @@ -20,6 +20,7 @@ #include #include +#include #include #include @@ -121,6 +122,102 @@ FreeHttpsCaCerts: FreePool (HttpsCaCerts); } +/** + Read the list of trusted cipher suites from the fw_cfg file + "etc/edk2/https/ciphers", and store it to + gEdkiiHttpTlsCipherListGuid:EDKII_HTTP_TLS_CIPHER_LIST_VARIABLE. + + The contents are propagated by NetworkPkg/HttpDxe to NetworkPkg/TlsDxe; the + list is processed by the latter. +**/ +STATIC +VOID +SetCipherSuites ( + VOID + ) +{ + EFI_STATUS Status; + FIRMWARE_CONFIG_ITEM HttpsCiphersItem; + UINTN HttpsCiphersSize; + VOID *HttpsCiphers; + + Status = QemuFwCfgFindFile ("etc/edk2/https/ciphers", &HttpsCiphersItem, + &HttpsCiphersSize); + if (EFI_ERROR (Status)) { + DEBUG ((DEBUG_VERBOSE, "%a:%a: not touching cipher suites\n", + gEfiCallerBaseName, __FUNCTION__)); + return; + } + // + // From this point on, any failure is fatal. An ordered cipher preference + // list is available from QEMU, thus we cannot let the firmware attempt HTTPS + // boot with either pre-existent or non-existent preferences. An empty set of + // cipher suites does not fail HTTPS boot automatically; the default cipher + // suite preferences would take effect, and we must prevent that. + // + // Delete the current EDKII_HTTP_TLS_CIPHER_LIST_VARIABLE if it exists. If + // the variable exists with EFI_VARIABLE_NON_VOLATILE attribute, we cannot + // make it volatile without deleting it first. + // + Status = gRT->SetVariable ( + EDKII_HTTP_TLS_CIPHER_LIST_VARIABLE, // VariableName + &gEdkiiHttpTlsCipherListGuid, // VendorGuid + 0, // Attributes + 0, // DataSize + NULL // Data + ); + if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) { + DEBUG ((DEBUG_ERROR, "%a:%a: failed to delete %g:\"%s\"\n", + gEfiCallerBaseName, __FUNCTION__, &gEdkiiHttpTlsCipherListGuid, + EDKII_HTTP_TLS_CIPHER_LIST_VARIABLE)); + goto Done; + } + + if (HttpsCiphersSize == 0) { + DEBUG ((DEBUG_ERROR, "%a:%a: list of cipher suites must not be empty\n", + gEfiCallerBaseName, __FUNCTION__)); + Status = EFI_INVALID_PARAMETER; + goto Done; + } + + HttpsCiphers = AllocatePool (HttpsCiphersSize); + if (HttpsCiphers == NULL) { + DEBUG ((DEBUG_ERROR, "%a:%a: failed to allocate HttpsCiphers\n", + gEfiCallerBaseName, __FUNCTION__)); + Status = EFI_OUT_OF_RESOURCES; + goto Done; + } + + QemuFwCfgSelectItem (HttpsCiphersItem); + QemuFwCfgReadBytes (HttpsCiphersSize, HttpsCiphers); + + Status = gRT->SetVariable ( + EDKII_HTTP_TLS_CIPHER_LIST_VARIABLE, // VariableName + &gEdkiiHttpTlsCipherListGuid, // VendorGuid + EFI_VARIABLE_BOOTSERVICE_ACCESS, // Attributes + HttpsCiphersSize, // DataSize + HttpsCiphers // Data + ); + if (EFI_ERROR (Status)) { + DEBUG ((DEBUG_ERROR, "%a:%a: failed to set %g:\"%s\"\n", + gEfiCallerBaseName, __FUNCTION__, &gEdkiiHttpTlsCipherListGuid, + EDKII_HTTP_TLS_CIPHER_LIST_VARIABLE)); + goto FreeHttpsCiphers; + } + + DEBUG ((DEBUG_VERBOSE, "%a:%a: stored list of cipher suites (%Lu byte(s))\n", + gEfiCallerBaseName, __FUNCTION__, (UINT64)HttpsCiphersSize)); + +FreeHttpsCiphers: + FreePool (HttpsCiphers); + +Done: + if (EFI_ERROR (Status)) { + ASSERT_EFI_ERROR (Status); + CpuDeadLoop (); + } +} + RETURN_STATUS EFIAPI TlsAuthConfigInit ( @@ -128,6 +225,7 @@ TlsAuthConfigInit ( ) { SetCaCerts (); + SetCipherSuites (); return RETURN_SUCCESS; } diff --git a/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.inf b/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.inf index 5f83582a83..40754ea5a2 100644 --- a/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.inf +++ b/OvmfPkg/Library/TlsAuthConfigLib/TlsAuthConfigLib.inf @@ -49,7 +49,8 @@ UefiRuntimeServicesTableLib [Guids] - gEfiTlsCaCertificateGuid ## PRODUCES ## Variable:L"TlsCaCertificate" + gEdkiiHttpTlsCipherListGuid ## PRODUCES ## Variable:L"HttpTlsCipherList" + gEfiTlsCaCertificateGuid ## PRODUCES ## Variable:L"TlsCaCertificate" [Depex] gEfiVariableWriteArchProtocolGuid