gRPC API

This reference is generated from the protocol buffer specification and documents the gRPC API of Tetragon.

The Tetragon API is an independant Go module that can be found in the Tetragon repository under api. The version 1 of this API is defined in github.com/cilium/tetragon/api/v1/tetragon.

tetragon/capabilities.proto

CapabilitiesType

NameNumberDescription
CAP_CHOWN0In a system with the [_POSIX_CHOWN_RESTRICTED] option defined, this overrides the restriction of changing file ownership and group ownership.
DAC_OVERRIDE1Override all DAC access, including ACL execute access if [_POSIX_ACL] is defined. Excluding DAC access covered by CAP_LINUX_IMMUTABLE.
CAP_DAC_READ_SEARCH2Overrides all DAC restrictions regarding read and search on files and directories, including ACL restrictions if [_POSIX_ACL] is defined. Excluding DAC access covered by "$1"_LINUX_IMMUTABLE.
CAP_FOWNER3Overrides all restrictions about allowed operations on files, where file owner ID must be equal to the user ID, except where CAP_FSETID is applicable. It doesn't override MAC and DAC restrictions.
CAP_FSETID4Overrides the following restrictions that the effective user ID shall match the file owner ID when setting the S_ISUID and S_ISGID bits on that file; that the effective group ID (or one of the supplementary group IDs) shall match the file owner ID when setting the S_ISGID bit on that file; that the S_ISUID and S_ISGID bits are cleared on successful return from chown(2) (not implemented).
CAP_KILL5Overrides the restriction that the real or effective user ID of a process sending a signal must match the real or effective user ID of the process receiving the signal.
CAP_SETGID6Allows forged gids on socket credentials passing.
CAP_SETUID7Allows forged pids on socket credentials passing.
CAP_SETPCAP8Without VFS support for capabilities: Transfer any capability in your permitted set to any pid, remove any capability in your permitted set from any pid With VFS support for capabilities (neither of above, but) Add any capability from current's capability bounding set to the current process' inheritable set Allow taking bits out of capability bounding set Allow modification of the securebits for a process
CAP_LINUX_IMMUTABLE9Allow modification of S_IMMUTABLE and S_APPEND file attributes
CAP_NET_BIND_SERVICE10Allows binding to ATM VCIs below 32
CAP_NET_BROADCAST11Allow broadcasting, listen to multicast
CAP_NET_ADMIN12Allow activation of ATM control sockets
CAP_NET_RAW13Allow binding to any address for transparent proxying (also via NET_ADMIN)
CAP_IPC_LOCK14Allow mlock and mlockall (which doesn't really have anything to do with IPC)
CAP_IPC_OWNER15Override IPC ownership checks
CAP_SYS_MODULE16Insert and remove kernel modules - modify kernel without limit
CAP_SYS_RAWIO17Allow sending USB messages to any device via /dev/bus/usb
CAP_SYS_CHROOT18Allow use of chroot()
CAP_SYS_PTRACE19Allow ptrace() of any process
CAP_SYS_PACCT20Allow configuration of process accounting
CAP_SYS_ADMIN21Allow everything under CAP_BPF and CAP_PERFMON for backward compatibility
CAP_SYS_BOOT22Allow use of reboot()
CAP_SYS_NICE23Allow setting cpu affinity on other processes
CAP_SYS_RESOURCE24Control memory reclaim behavior
CAP_SYS_TIME25Allow setting the real-time clock
CAP_SYS_TTY_CONFIG26Allow vhangup() of tty
CAP_MKNOD27Allow the privileged aspects of mknod()
CAP_LEASE28Allow taking of leases on files
CAP_AUDIT_WRITE29Allow writing the audit log via unicast netlink socket
CAP_AUDIT_CONTROL30Allow configuration of audit via unicast netlink socket
CAP_SETFCAP31Set or remove capabilities on files
CAP_MAC_OVERRIDE32Override MAC access. The base kernel enforces no MAC policy. An LSM may enforce a MAC policy, and if it does and it chooses to implement capability based overrides of that policy, this is the capability it should use to do so.
CAP_MAC_ADMIN33Allow MAC configuration or state changes. The base kernel requires no MAC configuration. An LSM may enforce a MAC policy, and if it does and it chooses to implement capability based checks on modifications to that policy or the data required to maintain it, this is the capability it should use to do so.
CAP_SYSLOG34Allow configuring the kernel's syslog (printk behaviour)
CAP_WAKE_ALARM35Allow triggering something that will wake the system
CAP_BLOCK_SUSPEND36Allow preventing system suspends
CAP_AUDIT_READ37Allow reading the audit log via multicast netlink socket
CAP_PERFMON38Allow system performance and observability privileged operations using perf_events, i915_perf and other kernel subsystems
CAP_BPF39CAP_BPF allows the following BPF operations: - Creating all types of BPF maps - Advanced verifier features - Indirect variable access - Bounded loops - BPF to BPF function calls - Scalar precision tracking - Larger complexity limits - Dead code elimination - And potentially other features - Loading BPF Type Format (BTF) data - Retrieve xlated and JITed code of BPF programs - Use bpf_spin_lock() helper CAP_PERFMON relaxes the verifier checks further: - BPF progs can use of pointer-to-integer conversions - speculation attack hardening measures are bypassed - bpf_probe_read to read arbitrary kernel memory is allowed - bpf_trace_printk to print kernel memory is allowed CAP_SYS_ADMIN is required to use bpf_probe_write_user. CAP_SYS_ADMIN is required to iterate system wide loaded programs, maps, links, BTFs and convert their IDs to file descriptors. CAP_PERFMON and CAP_BPF are required to load tracing programs. CAP_NET_ADMIN and CAP_BPF are required to load networking programs.
CAP_CHECKPOINT_RESTORE40Allow writing to ns_last_pid

ProcessPrivilegesChanged

Reasons of why the process privileges changed.

NameNumberDescription
PRIVILEGES_CHANGED_UNSET0
PRIVILEGES_RAISED_EXEC_FILE_CAP1A privilege elevation happened due to the execution of a binary with file capability sets. The kernel supports associating capability sets with an executable file using setcap command. The file capability sets are stored in an extended attribute (see https://man7.org/linux/man-pages/man7/xattr.7.html) named security.capability. The file capability sets, in conjunction with the capability sets of the process, determine the process capabilities and privileges after the execve system call. For further reference, please check sections File capability extended attribute versioning and Namespaced file capabilities of the capabilities man pages: https://man7.org/linux/man-pages/man7/capabilities.7.html. The new granted capabilities can be listed inside the process object.
PRIVILEGES_RAISED_EXEC_FILE_SETUID2A privilege elevation happened due to the execution of a binary with set-user-ID to root. When a process with nonzero UIDs executes a binary with a set-user-ID to root also known as suid-root executable, then the kernel switches the effective user ID to 0 (root) which is a privilege elevation operation since it grants access to resources owned by the root user. The effective user ID is listed inside the process_credentials part of the process object. For further reading, section Capabilities and execution of programs by root of https://man7.org/linux/man-pages/man7/capabilities.7.html. Afterward the kernel recalculates the capability sets of the process and grants all capabilities in the permitted and effective capability sets, except those masked out by the capability bounding set. If the binary also have file capability sets then these bits are honored and the process gains just the capabilities granted by the file capability sets (i.e., not all capabilities, as it would occur when executing a set-user-ID to root binary that does not have any associated file capabilities). This is described in section Set-user-ID-root programs that have file capabilities of https://man7.org/linux/man-pages/man7/capabilities.7.html. The new granted capabilities can be listed inside the process object. There is one exception for the special treatments of set-user-ID to root execution receiving all capabilities, if the SecBitNoRoot bit of the Secure bits is set, then the kernel does not grant any capability. Please check section: The securebits flags: establishing a capabilities-only environment of the capabilities man pages: https://man7.org/linux/man-pages/man7/capabilities.7.html
PRIVILEGES_RAISED_EXEC_FILE_SETGID3A privilege elevation happened due to the execution of a binary with set-group-ID to root. When a process with nonzero GIDs executes a binary with a set-group-ID to root, the kernel switches the effective group ID to 0 (root) which is a privilege elevation operation since it grants access to resources owned by the root group. The effective group ID is listed inside the process_credentials part of the process object.

SecureBitsType

NameNumberDescription
SecBitNotSet0
SecBitNoRoot1When set UID 0 has no special privileges. When unset, inheritance of root-permissions and suid-root executable under compatibility mode is supported. If the effective uid of the new process is 0 then the effective and inheritable bitmasks of the executable file is raised. If the real uid is 0, the effective (legacy) bit of the executable file is raised.
SecBitNoRootLocked2Make bit-0 SecBitNoRoot immutable
SecBitNoSetUidFixup4When set, setuid to/from uid 0 does not trigger capability-"fixup". When unset, to provide compatiblility with old programs relying on set*uid to gain/lose privilege, transitions to/from uid 0 cause capabilities to be gained/lost.
SecBitNoSetUidFixupLocked8Make bit-2 SecBitNoSetUidFixup immutable
SecBitKeepCaps16When set, a process can retain its capabilities even after transitioning to a non-root user (the set-uid fixup suppressed by bit 2). Bit-4 is cleared when a process calls exec(); setting both bit 4 and 5 will create a barrier through exec that no exec()'d child can use this feature again.
SecBitKeepCapsLocked32Make bit-4 SecBitKeepCaps immutable
SecBitNoCapAmbientRaise64When set, a process cannot add new capabilities to its ambient set.
SecBitNoCapAmbientRaiseLocked128Make bit-6 SecBitNoCapAmbientRaise immutable

tetragon/bpf.proto

BpfCmd

NameNumberDescription
BPF_MAP_CREATE0Create a map and return a file descriptor that refers to the map.
BPF_MAP_LOOKUP_ELEM1Look up an element with a given key in the map referred to by the file descriptor map_fd.
BPF_MAP_UPDATE_ELEM2Create or update an element (key/value pair) in a specified map.
BPF_MAP_DELETE_ELEM3Look up and delete an element by key in a specified map.
BPF_MAP_GET_NEXT_KEY4Look up an element by key in a specified map and return the key of the next element. Can be used to iterate over all elements in the map.
BPF_PROG_LOAD5Verify and load an eBPF program, returning a new file descriptor associated with the program.
BPF_OBJ_PIN6Pin an eBPF program or map referred by the specified bpf_fd to the provided pathname on the filesystem.
BPF_OBJ_GET7Open a file descriptor for the eBPF object pinned to the specified pathname.
BPF_PROG_ATTACH8Attach an eBPF program to a target_fd at the specified attach_type hook.
BPF_PROG_DETACH9Detach the eBPF program associated with the target_fd at the hook specified by attach_type.
BPF_PROG_TEST_RUN10Run the eBPF program associated with the prog_fd a repeat number of times against a provided program context ctx_in and data data_in, and return the modified program context ctx_out, data_out (for example, packet data), result of the execution retval, and duration of the test run.
BPF_PROG_GET_NEXT_ID11Fetch the next eBPF program currently loaded into the kernel.
BPF_MAP_GET_NEXT_ID12Fetch the next eBPF map currently loaded into the kernel.
BPF_PROG_GET_FD_BY_ID13Open a file descriptor for the eBPF program corresponding to prog_id.
BPF_MAP_GET_FD_BY_ID14Open a file descriptor for the eBPF map corresponding to map_id.
BPF_OBJ_GET_INFO_BY_FD15Obtain information about the eBPF object corresponding to bpf_fd.
BPF_PROG_QUERY16Obtain information about eBPF programs associated with the specified attach_type hook.
BPF_RAW_TRACEPOINT_OPEN17Attach an eBPF program to a tracepoint name to access kernel internal arguments of the tracepoint in their raw form.
BPF_BTF_LOAD18Verify and load BPF Type Format (BTF) metadata into the kernel, returning a new file descriptor associated with the metadata.
BPF_BTF_GET_FD_BY_ID19Open a file descriptor for the BPF Type Format (BTF) corresponding to btf_id.
BPF_TASK_FD_QUERY20Obtain information about eBPF programs associated with the target process identified by pid and fd.
BPF_MAP_LOOKUP_AND_DELETE_ELEM21Look up an element with the given key in the map referred to by the file descriptor fd, and if found, delete the element.
BPF_MAP_FREEZE22Freeze the permissions of the specified map.
BPF_BTF_GET_NEXT_ID23Fetch the next BPF Type Format (BTF) object currently loaded into the kernel.
BPF_MAP_LOOKUP_BATCH24Iterate and fetch multiple elements in a map.
BPF_MAP_LOOKUP_AND_DELETE_BATCH25Iterate and delete all elements in a map.
BPF_MAP_UPDATE_BATCH26Update multiple elements in a map by key.
BPF_MAP_DELETE_BATCH27Delete multiple elements in a map by key.
BPF_LINK_CREATE28Attach an eBPF program to a target_fd at the specified attach_type hook and return a file descriptor handle for managing the link.
BPF_LINK_UPDATE29Update the eBPF program in the specified link_fd to new_prog_fd.
BPF_LINK_GET_FD_BY_ID30Open a file descriptor for the eBPF Link corresponding to link_id.
BPF_LINK_GET_NEXT_ID31Fetch the next eBPF link currently loaded into the kernel.
BPF_ENABLE_STATS32Enable eBPF runtime statistics gathering.
BPF_ITER_CREATE33Create an iterator on top of the specified link_fd (as previously created using BPF_LINK_CREATE) and return a file descriptor that can be used to trigger the iteration.
BPF_LINK_DETACH34Forcefully detach the specified link_fd from its corresponding attachment point.
BPF_PROG_BIND_MAP35Bind a map to the lifetime of an eBPF program.
BPF_TOKEN_CREATE36Create BPF token with embedded information about what can be passed as an extra parameter to various bpf() syscall commands to grant BPF subsystem functionality to unprivileged processes.

BpfProgramType

NameNumberDescription
BPF_PROG_TYPE_UNSPEC0
BPF_PROG_TYPE_SOCKET_FILTER1
BPF_PROG_TYPE_KPROBE2
BPF_PROG_TYPE_SCHED_CLS3
BPF_PROG_TYPE_SCHED_ACT4
BPF_PROG_TYPE_TRACEPOINT5
BPF_PROG_TYPE_XDP6
BPF_PROG_TYPE_PERF_EVENT7
BPF_PROG_TYPE_CGROUP_SKB8
BPF_PROG_TYPE_CGROUP_SOCK9
BPF_PROG_TYPE_LWT_IN10
BPF_PROG_TYPE_LWT_OUT11
BPF_PROG_TYPE_LWT_XMIT12
BPF_PROG_TYPE_SOCK_OPS13
BPF_PROG_TYPE_SK_SKB14
BPF_PROG_TYPE_CGROUP_DEVICE15
BPF_PROG_TYPE_SK_MSG16
BPF_PROG_TYPE_RAW_TRACEPOINT17
BPF_PROG_TYPE_CGROUP_SOCK_ADDR18
BPF_PROG_TYPE_LWT_SEG6LOCAL19
BPF_PROG_TYPE_LIRC_MODE220
BPF_PROG_TYPE_SK_REUSEPORT21
BPF_PROG_TYPE_FLOW_DISSECTOR22
BPF_PROG_TYPE_CGROUP_SYSCTL23
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE24
BPF_PROG_TYPE_CGROUP_SOCKOPT25
BPF_PROG_TYPE_TRACING26
BPF_PROG_TYPE_STRUCT_OPS27
BPF_PROG_TYPE_EXT28
BPF_PROG_TYPE_LSM29
BPF_PROG_TYPE_SK_LOOKUP30
BPF_PROG_TYPE_SYSCALL31
BPF_PROG_TYPE_NETFILTER32

tetragon/tetragon.proto

BinaryProperties

FieldTypeLabelDescription
setuidgoogle.protobuf.UInt32ValueIf set then this is the set user ID used for execution
setgidgoogle.protobuf.UInt32ValueIf set then this is the set group ID used for execution
privileges_changedProcessPrivilegesChangedrepeatedThe reasons why this binary execution changed privileges. Usually this happens when the process executes a binary with the set-user-ID to root or file capability sets. The final granted privileges can be listed inside the process_credentials or capabilities fields part of of the process object.
fileFilePropertiesFile properties in case the executed binary is: 1. An anonymous shared memory file https://man7.org/linux/man-pages/man7/shm_overview.7.html. 2. An anonymous file obtained with memfd API https://man7.org/linux/man-pages/man2/memfd_create.2.html. 3. Or it was deleted from the file system.

Capabilities

FieldTypeLabelDescription
permittedCapabilitiesTyperepeatedPermitted set indicates what capabilities the process can use. This is a limiting superset for the effective capabilities that the thread may assume. It is also a limiting superset for the capabilities that may be added to the inheritable set by a thread without the CAP_SETPCAP in its effective set.
effectiveCapabilitiesTyperepeatedEffective set indicates what capabilities are active in a process. This is the set used by the kernel to perform permission checks for the thread.
inheritableCapabilitiesTyperepeatedInheritable set indicates which capabilities will be inherited by the current process when running as a root user.

Container

FieldTypeLabelDescription
idstringIdentifier of the container.
namestringName of the container.
imageImageImage of the container.
start_timegoogle.protobuf.TimestampStart time of the container.
pidgoogle.protobuf.UInt32ValueProcess identifier in the container namespace.
maybe_exec_probeboolIf this is set true, it means that the process might have been originated from a Kubernetes exec probe. For this field to be true, the following must be true: 1. The binary field matches the first element of the exec command list for either liveness or readiness probe excluding the basename. For example, "/bin/ls" and "ls" are considered a match. 2. The arguments field exactly matches the rest of the exec command list.

CreateContainer

CreateContainer informs the agent that a container was created This is intented to be used by OCI hooks (but not limited to them) and corresponds to the CreateContainer hook: https://github.com/opencontainers/runtime-spec/blob/main/config.md#createcontainer-hooks.

The containerName, containerID, podName, podUID, and podNamespace fields are retrieved from the annotations as a convenience, and may be left empty if the corresponding annotations are not found.

FieldTypeLabelDescription
cgroupsPathstringcgroupsPath is the cgroups path for the container. The path is expected to be relative to the cgroups mountpoint. See: https://github.com/opencontainers/runtime-spec/blob/58ec43f9fc39e0db229b653ae98295bfde74aeab/specs-go/config.go#L174
rootDirstringrootDir is the absolute path of the root directory of the container. See: https://github.com/opencontainers/runtime-spec/blob/main/specs-go/config.go#L174
annotationsCreateContainer.AnnotationsEntryrepeatedannotations are the run-time annotations for the container see https://github.com/opencontainers/runtime-spec/blob/main/config.md#annotations
containerNamestringcontainerName is the name of the container
containerIDstringcontainerID is the id of the container
podNamestringpodName is the pod name
podUIDstringpodUID is the pod uid
podNamespacestringpodNamespace is the namespace of the pod

CreateContainer.AnnotationsEntry

FieldTypeLabelDescription
keystring
valuestring

FileProperties

FieldTypeLabelDescription
inodeInodePropertiesInode of the file
pathstringPath of the file

GetHealthStatusRequest

FieldTypeLabelDescription
event_setHealthStatusTyperepeated

GetHealthStatusResponse

FieldTypeLabelDescription
health_statusHealthStatusrepeated

HealthStatus

FieldTypeLabelDescription
eventHealthStatusType
statusHealthStatusResult
detailsstring

Image

FieldTypeLabelDescription
idstringIdentifier of the container image composed of the registry path and the sha256.
namestringName of the container image composed of the registry path and the tag.

InodeProperties

FieldTypeLabelDescription
numberuint64The inode number
linksgoogle.protobuf.UInt32ValueThe inode links on the file system. If zero means the file is only in memory

KernelModule

FieldTypeLabelDescription
namestringKernel module name
signature_okgoogle.protobuf.BoolValueIf true the module signature was verified successfully. Depends on kernels compiled with CONFIG_MODULE_SIG option, for details please read: https://www.kernel.org/doc/Documentation/admin-guide/module-signing.rst
taintedTaintedBitsTyperepeatedThe module tainted flags that will be applied on the kernel. For further details please read: https://docs.kernel.org/admin-guide/tainted-kernels.html

KprobeArgument

FieldTypeLabelDescription
string_argstring
int_argint32
skb_argKprobeSkb
size_arguint64
bytes_argbytes
path_argKprobePath
file_argKprobeFile
truncated_bytes_argKprobeTruncatedBytes
sock_argKprobeSock
cred_argKprobeCred
long_argint64
bpf_attr_argKprobeBpfAttr
perf_event_argKprobePerfEvent
bpf_map_argKprobeBpfMap
uint_arguint32
user_namespace_argKprobeUserNamespaceDeprecated.
capability_argKprobeCapability
process_credentials_argProcessCredentials
user_ns_argUserNamespace
module_argKernelModule
kernel_cap_t_argstringCapabilities in hexadecimal format.
cap_inheritable_argstringCapabilities inherited by a forked process in hexadecimal format.
cap_permitted_argstringCapabilities that are currently permitted in hexadecimal format.
cap_effective_argstringCapabilities that are actually used in hexadecimal format.
linux_binprm_argKprobeLinuxBinprm
net_dev_argKprobeNetDev
bpf_cmd_argBpfCmd
syscall_idSyscallId
labelstring

KprobeBpfAttr

FieldTypeLabelDescription
ProgTypestring
InsnCntuint32
ProgNamestring

KprobeBpfMap

FieldTypeLabelDescription
MapTypestring
KeySizeuint32
ValueSizeuint32
MaxEntriesuint32
MapNamestring

KprobeCapability

FieldTypeLabelDescription
valuegoogle.protobuf.Int32Value
namestring

KprobeCred

FieldTypeLabelDescription
permittedCapabilitiesTyperepeated
effectiveCapabilitiesTyperepeated
inheritableCapabilitiesTyperepeated

KprobeFile

FieldTypeLabelDescription
mountstring
pathstring
flagsstring
permissionstring

KprobeLinuxBinprm

FieldTypeLabelDescription
pathstring
flagsstring
permissionstring

KprobeNetDev

FieldTypeLabelDescription
namestring

KprobePath

FieldTypeLabelDescription
mountstring
pathstring
flagsstring
permissionstring

KprobePerfEvent

FieldTypeLabelDescription
KprobeFuncstring
Typestring
Configuint64
ProbeOffsetuint64

KprobeSkb

FieldTypeLabelDescription
hashuint32
lenuint32
priorityuint32
markuint32
saddrstring
daddrstring
sportuint32
dportuint32
protouint32
sec_path_lenuint32
sec_path_olenuint32
protocolstring
familystring

KprobeSock

FieldTypeLabelDescription
familystring
typestring
protocolstring
markuint32
priorityuint32
saddrstring
daddrstring
sportuint32
dportuint32
cookieuint64
statestring

KprobeTruncatedBytes

FieldTypeLabelDescription
bytes_argbytes
orig_sizeuint64

KprobeUserNamespace

FieldTypeLabelDescription
levelgoogle.protobuf.Int32Value
ownergoogle.protobuf.UInt32Value
groupgoogle.protobuf.UInt32Value
nsNamespace

Namespace

FieldTypeLabelDescription
inumuint32Inode number of the namespace.
is_hostboolIndicates if namespace belongs to host.

Namespaces

FieldTypeLabelDescription
utsNamespaceHostname and NIS domain name.
ipcNamespaceSystem V IPC, POSIX message queues.
mntNamespaceMount points.
pidNamespaceProcess IDs.
pid_for_childrenNamespaceProcess IDs for children processes.
netNamespaceNetwork devices, stacks, ports, etc.
timeNamespaceBoot and monotonic clocks.
time_for_childrenNamespaceBoot and monotonic clocks for children processes.
cgroupNamespaceCgroup root directory.
userNamespaceUser and group IDs.

Pod

FieldTypeLabelDescription
namespacestringKubernetes namespace of the Pod.
namestringName of the Pod.
containerContainerContainer of the Pod from which the process that triggered the event originates.
pod_labelsPod.PodLabelsEntryrepeatedContains all the labels of the pod.
workloadstringKubernetes workload of the Pod.
workload_kindstringKubernetes workload kind (e.g. "Deployment", "DaemonSet") of the Pod.

Pod.PodLabelsEntry

FieldTypeLabelDescription
keystring
valuestring

Process

FieldTypeLabelDescription
exec_idstringExec ID uniquely identifies the process over time across all the nodes in the cluster.
pidgoogle.protobuf.UInt32ValueProcess identifier from host PID namespace.
uidgoogle.protobuf.UInt32ValueThe effective User identifier used for permission checks. This field maps to the 'ProcessCredentials.euid' field. Run with the --enable-process-cred flag to enable 'ProcessCredentials' and get all the User and Group identifiers.
cwdstringCurrent working directory of the process.
binarystringAbsolute path of the executed binary.
argumentsstringArguments passed to the binary at execution.
flagsstringFlags are for debugging purposes only and should not be considered a reliable source of information. They hold various information about which syscalls generated events, use of internal Tetragon buffers, errors and more. - execve This event is generated by an execve syscall for a new process. See procFs for the other option. A correctly formatted event should either set execve or procFS (described next). - procFS This event is generated from a proc interface. This happens at Tetragon init when existing processes are being loaded into Tetragon event buffer. All events should have either execve or procFS set. - truncFilename Indicates a truncated processes filename because the buffer size is too small to contain the process filename. Consider increasing buffer size to avoid this. - truncArgs Indicates truncated the processes arguments because the buffer size was too small to contain all exec args. Consider increasing buffer size to avoid this. - taskWalk Primarily useful for debugging. Indicates a walked process hierarchy to find a parent process in the Tetragon buffer. This may happen when we did not receive an exec event for the immediate parent of a process. Typically means we are looking at a fork that in turn did another fork we don't currently track fork events exactly and instead push an event with the original parent exec data. This flag can provide this insight into the event if needed. - miss An error flag indicating we could not find parent info in the Tetragon event buffer. If this is set it should be reported to Tetragon developers for debugging. Tetragon will do its best to recover information about the process from available kernel data structures instead of using cached info in this case. However, args will not be available. - needsAUID An internal flag for Tetragon to indicate the audit has not yet been resolved. The BPF hooks look at this flag to determine if probing the audit system is necessary. - errorFilename An error flag indicating an error happened while reading the filename. If this is set it should be reported to Tetragon developers for debugging. - errorArgs An error flag indicating an error happened while reading the process args. If this is set it should be reported to Tetragon developers for debugging - needsCWD An internal flag for Tetragon to indicate the current working directory has not yet been resolved. The Tetragon hooks look at this flag to determine if probing the CWD is necessary. - noCWDSupport Indicates that CWD is removed from the event because the buffer size is too small. Consider increasing buffer size to avoid this. - rootCWD Indicates that CWD is the root directory. This is necessary to inform readers the CWD is not in the event buffer and is '/' instead. - errorCWD An error flag indicating an error occurred while reading the CWD of a process. If this is set it should be reported to Tetragon developers for debugging. - clone Indicates the process issued a clone before exec*. This is the general flow to exec* a new process, however its possible to replace the current process with a new process by doing an exec* without a clone. In this case the flag will be omitted and the same PID will be used by the kernel for both the old process and the newly exec'd process.
start_timegoogle.protobuf.TimestampStart time of the execution.
auidgoogle.protobuf.UInt32ValueAudit user ID, this ID is assigned to a user upon login and is inherited by every process even when the user's identity changes. For example, by switching user accounts with su - john.
podPodInformation about the the Kubernetes Pod where the event originated.
dockerstringThe 15 first digits of the container ID.
parent_exec_idstringExec ID of the parent process.
refcntuint32Reference counter from the Tetragon process cache.
capCapabilitiesSet of capabilities that define the permissions the process can execute with.
nsNamespacesLinux namespaces of the process, disabled by default, can be enabled by the --enable-process-ns flag.
tidgoogle.protobuf.UInt32ValueThread ID, note that for the thread group leader, tid is equal to pid.
process_credentialsProcessCredentialsProcess credentials, disabled by default, can be enabled by the --enable-process-cred flag.
binary_propertiesBinaryPropertiesExecuted binary properties. This field is only available on ProcessExec events.
userUserRecordUserRecord contains user information about the event. It is only supported when i) Tetragon is running as a systemd service or directly on the host, and ii) when the flag --username-metadata is set to "unix". In this case, the information is retrieved from the traditional user database /etc/passwd and no name services lookups are performed. The resolution will only be attempted for processes in the host namespace. Note that this resolution happens in user-space, which means that mapping might have changed between the in-kernel BPF hook being executed and the username resolution.

ProcessCredentials

FieldTypeLabelDescription
uidgoogle.protobuf.UInt32ValueThe real user ID of the process' owner.
gidgoogle.protobuf.UInt32ValueThe real group ID of the process' owner.
euidgoogle.protobuf.UInt32ValueThe effective user ID used for permission checks.
egidgoogle.protobuf.UInt32ValueThe effective group ID used for permission checks.
suidgoogle.protobuf.UInt32ValueThe saved user ID.
sgidgoogle.protobuf.UInt32ValueThe saved group ID.
fsuidgoogle.protobuf.UInt32Valuethe filesystem user ID used for filesystem access checks. Usually equals the euid.
fsgidgoogle.protobuf.UInt32ValueThe filesystem group ID used for filesystem access checks. Usually equals the egid.
securebitsSecureBitsTyperepeatedSecure management flags
capsCapabilitiesSet of capabilities that define the permissions the process can execute with.
user_nsUserNamespaceUser namespace where the UIDs, GIDs and capabilities are relative to.

ProcessExec

FieldTypeLabelDescription
processProcessProcess that triggered the exec.
parentProcessImmediate parent of the process.
ancestorsProcessrepeatedAncestors of the process beyond the immediate parent.

ProcessExit

FieldTypeLabelDescription
processProcessProcess that triggered the exit.
parentProcessImmediate parent of the process.
signalstringSignal that the process received when it exited, for example SIGKILL or SIGTERM (list all signal names with kill -l). If there is no signal handler implemented for a specific process, we report the exit status code that can be found in the status field.
statusuint32Status code on process exit. For example, the status code can indicate if an error was encountered or the program exited successfully.
timegoogle.protobuf.TimestampDate and time of the event.

ProcessKprobe

FieldTypeLabelDescription
processProcessProcess that triggered the kprobe.
parentProcessImmediate parent of the process.
function_namestringSymbol on which the kprobe was attached.
argsKprobeArgumentrepeatedArguments definition of the observed kprobe.
returnKprobeArgumentReturn value definition of the observed kprobe.
actionKprobeActionAction performed when the kprobe matched.
kernel_stack_traceStackTraceEntryrepeatedKernel stack trace to the call.
policy_namestringName of the Tracing Policy that created that kprobe.
return_actionKprobeActionAction performed when the return kprobe executed.
messagestringShort message of the Tracing Policy to inform users what is going on.
tagsstringrepeatedTags of the Tracing Policy to categorize the event.
user_stack_traceStackTraceEntryrepeatedUser-mode stack trace to the call.

ProcessLoader

loader sensor event triggered for loaded binary/library

FieldTypeLabelDescription
processProcess
pathstring
buildidbytes

ProcessLsm

FieldTypeLabelDescription
processProcess
parentProcess
function_namestringLSM hook name.
policy_namestringName of the policy that created that LSM hook.
messagestringShort message of the Tracing Policy to inform users what is going on.
argsKprobeArgumentrepeatedArguments definition of the observed LSM hook.
actionKprobeActionAction performed when the LSM hook matched.
tagsstringrepeatedTags of the Tracing Policy to categorize the event.
ima_hashstringIMA file hash. Format algorithm:value.

ProcessTracepoint

FieldTypeLabelDescription
processProcessProcess that triggered the tracepoint.
parentProcessImmediate parent of the process.
subsysstringSubsystem of the tracepoint.
eventstringEvent of the subsystem.
argsKprobeArgumentrepeatedArguments definition of the observed tracepoint. TODO: once we implement all we want, rename KprobeArgument to GenericArgument
policy_namestringName of the policy that created that tracepoint.
actionKprobeActionAction performed when the tracepoint matched.
messagestringShort message of the Tracing Policy to inform users what is going on.
tagsstringrepeatedTags of the Tracing Policy to categorize the event.

ProcessUprobe

FieldTypeLabelDescription
processProcess
parentProcess
pathstring
symbolstring
policy_namestringName of the policy that created that uprobe.
messagestringShort message of the Tracing Policy to inform users what is going on.
argsKprobeArgumentrepeatedArguments definition of the observed uprobe.
tagsstringrepeatedTags of the Tracing Policy to categorize the event.

RuntimeHookRequest

RuntimeHookRequest synchronously propagates information to the agent about run-time state.

FieldTypeLabelDescription
createContainerCreateContainer

RuntimeHookResponse

StackTraceEntry

FieldTypeLabelDescription
addressuint64linear address of the function in kernel or user space.
offsetuint64offset is the offset into the native instructions for the function.
symbolstringsymbol is the symbol name of the function.
modulestringmodule path for user space addresses.

SyscallId

FieldTypeLabelDescription
iduint32
abistring

Test

FieldTypeLabelDescription
arg0uint64
arg1uint64
arg2uint64
arg3uint64

UserNamespace

FieldTypeLabelDescription
levelgoogle.protobuf.Int32ValueNested level of the user namespace. Init or host user namespace is at level 0.
uidgoogle.protobuf.UInt32ValueThe owner user ID of the namespace
gidgoogle.protobuf.UInt32ValueThe owner group ID of the namepace.
nsNamespaceThe user namespace details that include the inode number of the namespace.

UserRecord

User records

FieldTypeLabelDescription
namestringThe UNIX username for this record. Corresponds to pw_name field of struct passwd and the sp_namp field of struct spwd.

HealthStatusResult

NameNumberDescription
HEALTH_STATUS_UNDEF0
HEALTH_STATUS_RUNNING1
HEALTH_STATUS_STOPPED2
HEALTH_STATUS_ERROR3

HealthStatusType

NameNumberDescription
HEALTH_STATUS_TYPE_UNDEF0
HEALTH_STATUS_TYPE_STATUS1

KprobeAction

NameNumberDescription
KPROBE_ACTION_UNKNOWN0Unknown action
KPROBE_ACTION_POST1Post action creates an event (default action).
KPROBE_ACTION_FOLLOWFD2Post action creates a mapping between file descriptors and file names.
KPROBE_ACTION_SIGKILL3Sigkill action synchronously terminates the process.
KPROBE_ACTION_UNFOLLOWFD4Post action removes a mapping between file descriptors and file names.
KPROBE_ACTION_OVERRIDE5Override action modifies the return value of the call.
KPROBE_ACTION_COPYFD6Post action dupplicates a mapping between file descriptors and file names.
KPROBE_ACTION_GETURL7GetURL action issue an HTTP Get request against an URL from userspace.
KPROBE_ACTION_DNSLOOKUP8GetURL action issue a DNS lookup against an URL from userspace.
KPROBE_ACTION_NOPOST9NoPost action suppresses the transmission of the event to userspace.
KPROBE_ACTION_SIGNAL10Signal action sends specified signal to the process.
KPROBE_ACTION_TRACKSOCK11TrackSock action tracks socket.
KPROBE_ACTION_UNTRACKSOCK12UntrackSock action un-tracks socket.
KPROBE_ACTION_NOTIFYENFORCER13NotifyEnforcer action notifies enforcer sensor.
KPROBE_ACTION_CLEANUPENFORCERNOTIFICATION14CleanupEnforcerNotification action cleanups any state left by NotifyEnforcer

TaintedBitsType

Tainted bits to indicate if the kernel was tainted. For further details: https://docs.kernel.org/admin-guide/tainted-kernels.html

NameNumberDescription
TAINT_UNSET0
TAINT_PROPRIETARY_MODULE1A proprietary module was loaded.
TAINT_FORCED_MODULE2A module was force loaded.
TAINT_FORCED_UNLOAD_MODULE4A module was force unloaded.
TAINT_STAGED_MODULE1024A staging driver was loaded.
TAINT_OUT_OF_TREE_MODULE4096An out of tree module was loaded.
TAINT_UNSIGNED_MODULE8192An unsigned module was loaded. Supported only on kernels built with CONFIG_MODULE_SIG option.
TAINT_KERNEL_LIVE_PATCH_MODULE32768The kernel has been live patched.
TAINT_TEST_MODULE262144Loading a test module.

tetragon/events.proto

AggregationInfo

AggregationInfo contains information about aggregation results.

FieldTypeLabelDescription
countuint64Total count of events in this aggregation time window.

AggregationOptions

AggregationOptions defines configuration options for aggregating events.

FieldTypeLabelDescription
window_sizegoogle.protobuf.DurationAggregation window size. Defaults to 15 seconds if this field is not set.
channel_buffer_sizeuint64Size of the buffer for the aggregator to receive incoming events. If the buffer becomes full, the aggregator will log a warning and start dropping incoming events.

CapFilter

Filter over a set of Linux process capabilities. See message Capabilities for more info. WARNING: Multiple sets are ANDed. For example, if the permitted filter matches, but the effective filter does not, the filter will NOT match.

FieldTypeLabelDescription
permittedCapFilterSetFilter over the set of permitted capabilities.
effectiveCapFilterSetFilter over the set of effective capabilities.
inheritableCapFilterSetFilter over the set of inheritable capabilities.

CapFilterSet

Capability set to filter over. NOTE: you may specify only ONE set here.

FieldTypeLabelDescription
anyCapabilitiesTyperepeatedMatch if the capability set contains any of the capabilities defined in this filter.
allCapabilitiesTyperepeatedMatch if the capability set contains all of the capabilities defined in this filter.
exactlyCapabilitiesTyperepeatedMatch if the capability set exactly matches all of the capabilities defined in this filter.
noneCapabilitiesTyperepeatedMatch if the capability set contains none of the capabilities defined in this filter.

FieldFilter

FieldTypeLabelDescription
event_setEventTyperepeatedEvent types to filter or undefined to filter over all event types.
fieldsgoogle.protobuf.FieldMaskFields to include or exclude.
actionFieldFilterActionWhether to include or exclude fields.
invert_event_setgoogle.protobuf.BoolValueWhether or not the event set filter should be inverted.

Filter

FieldTypeLabelDescription
binary_regexstringrepeated
namespacestringrepeated
health_checkgoogle.protobuf.BoolValue
piduint32repeated
pid_setuint32repeatedFilter by the PID of a process and any of its descendants. Note that this filter is intended for testing and development purposes only and should not be used in production. In particular, PID cycling in the OS over longer periods of time may cause unexpected events to pass this filter.
event_setEventTyperepeated
pod_regexstringrepeatedFilter by process.pod.name field using RE2 regular expression syntax: https://github.com/google/re2/wiki/Syntax
arguments_regexstringrepeatedFilter by process.arguments field using RE2 regular expression syntax: https://github.com/google/re2/wiki/Syntax
labelsstringrepeatedFilter events by pod labels using Kubernetes label selector syntax: https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#label-selectors Note that this filter never matches events without the pod field (i.e. host process events).
policy_namesstringrepeatedFilter events by tracing policy names
capabilitiesCapFilterFilter events by Linux process capability
parent_binary_regexstringrepeatedFilter parent process' binary using RE2 regular expression syntax.
cel_expressionstringrepeatedFilter using CEL expressions.

GetEventsRequest

FieldTypeLabelDescription
allow_listFilterrepeatedallow_list specifies a list of filters to apply to only return certain events. If multiple filters are specified, at least one of them has to match for an event to be included in the results.
deny_listFilterrepeateddeny_list specifies a list of filters to apply to exclude certain events from the results. If multiple filters are specified, at least one of them has to match for an event to be excluded. If both allow_list and deny_list are specified, the results contain the set difference allow_list - deny_list.
aggregation_optionsAggregationOptionsaggregation_options configures aggregation options for this request. If this field is not set, responses will not be aggregated. Note that currently only process_accept and process_connect events are aggregated. Other events remain unaggregated.
field_filtersFieldFilterrepeatedFields to include or exclude for events in the GetEventsResponse. Omitting this field implies that all fields will be included. Exclusion always takes precedence over inclusion in the case of conflicts.

GetEventsResponse

FieldTypeLabelDescription
process_execProcessExecProcessExec event includes information about the execution of binaries and other related process metadata.
process_exitProcessExitProcessExit event indicates how and when a process terminates.
process_kprobeProcessKprobeProcessKprobe event contains information about the pre-defined functions and the process that invoked them.
process_tracepointProcessTracepointProcessTracepoint contains information about the pre-defined tracepoint and the process that invoked them.
process_loaderProcessLoader
process_uprobeProcessUprobe
process_throttleProcessThrottle
process_lsmProcessLsm
testTest
rate_limit_infoRateLimitInfo
node_namestringName of the node where this event was observed.
timegoogle.protobuf.TimestampTimestamp at which this event was observed. For an aggregated response, this field to set to the timestamp at which the event was observed for the first time in a given aggregation time window.
aggregation_infoAggregationInfoaggregation_info contains information about aggregation results. This field is set only for aggregated responses.
cluster_namestringName of the cluster where this event was observed.

ProcessThrottle

FieldTypeLabelDescription
typeThrottleTypeThrottle type
cgroupstringCgroup name

RateLimitInfo

FieldTypeLabelDescription
number_of_dropped_process_eventsuint64

RedactionFilter

FieldTypeLabelDescription
matchFilterrepeatedDeprecated. Deprecated, do not use.
redactstringrepeatedRE2 regular expressions to use for redaction. Strings inside capture groups are redacted.
binary_regexstringrepeatedRE2 regular expression to match binary name. If supplied, redactions will only be applied to matching processes.

EventType

Represents the type of a Tetragon event.

NOTE: EventType constants must be in sync with the numbers used in the GetEventsResponse event oneof.

NameNumberDescription
UNDEF0
PROCESS_EXEC1
PROCESS_EXIT5
PROCESS_KPROBE9
PROCESS_TRACEPOINT10
PROCESS_LOADER11
PROCESS_UPROBE12
PROCESS_THROTTLE27
PROCESS_LSM28
TEST40000
RATE_LIMIT_INFO40001

FieldFilterAction

Determines the behavior of a field filter

NameNumberDescription
INCLUDE0
EXCLUDE1

ThrottleType

NameNumberDescription
THROTTLE_UNKNOWN0
THROTTLE_START1
THROTTLE_STOP2

tetragon/stack.proto

StackAddress

FieldTypeLabelDescription
addressuint64
symbolstring

StackTrace

FieldTypeLabelDescription
addressesStackAddressrepeated

StackTraceLabel

FieldTypeLabelDescription
keystring
countuint64

StackTraceNode

FieldTypeLabelDescription
addressStackAddress
countuint64
labelsStackTraceLabelrepeated
childrenStackTraceNoderepeated

tetragon/sensors.proto

AddTracingPolicyRequest

FieldTypeLabelDescription
yamlstring

AddTracingPolicyResponse

DeleteTracingPolicyRequest

FieldTypeLabelDescription
namestring
namespacestring

DeleteTracingPolicyResponse

DisableSensorRequest

FieldTypeLabelDescription
namestring

DisableSensorResponse

DisableTracingPolicyRequest

FieldTypeLabelDescription
namestring
namespacestring

DisableTracingPolicyResponse

DumpProcessCacheReqArgs

FieldTypeLabelDescription
skip_zero_refcntbool
exclude_execve_map_processesbool

DumpProcessCacheResArgs

FieldTypeLabelDescription
processesProcessInternalrepeated

EnableSensorRequest

FieldTypeLabelDescription
namestring

EnableSensorResponse

EnableTracingPolicyRequest

FieldTypeLabelDescription
namestring
namespacestring

EnableTracingPolicyResponse

GetDebugRequest

FieldTypeLabelDescription
flagConfigFlag
dumpDumpProcessCacheReqArgs

GetDebugResponse

FieldTypeLabelDescription
flagConfigFlag
levelLogLevel
processesDumpProcessCacheResArgs

GetStackTraceTreeRequest

FieldTypeLabelDescription
namestring

GetStackTraceTreeResponse

FieldTypeLabelDescription
rootStackTraceNode

GetVersionRequest

GetVersionResponse

FieldTypeLabelDescription
versionstring

ListSensorsRequest

ListSensorsResponse

FieldTypeLabelDescription
sensorsSensorStatusrepeated

ListTracingPoliciesRequest

ListTracingPoliciesResponse

FieldTypeLabelDescription
policiesTracingPolicyStatusrepeated

ProcessInternal

FieldTypeLabelDescription
processProcess
colorstring
refcntgoogle.protobuf.UInt32Value
refcnt_opsProcessInternal.RefcntOpsEntryrepeatedrefcnt_ops is a map of operations to refcnt change keys can be: - "process++": process increased refcnt (i.e. this process starts) - "process–": process decreased refcnt (i.e. this process exits) - "parent++": parent increased refcnt (i.e. a process starts that has this process as a parent) - "parent–": parent decreased refcnt (i.e. a process exits that has this process as a parent)

ProcessInternal.RefcntOpsEntry

FieldTypeLabelDescription
keystring
valueint32

RemoveSensorRequest

FieldTypeLabelDescription
namestring

RemoveSensorResponse

SensorStatus

FieldTypeLabelDescription
namestringname is the name of the sensor
enabledboolenabled marks whether the sensor is enabled
collectionstringcollection is the collection the sensor belongs to (typically a tracing policy)

SetDebugRequest

FieldTypeLabelDescription
flagConfigFlag
levelLogLevel

SetDebugResponse

FieldTypeLabelDescription
flagConfigFlag
levelLogLevel

TracingPolicyStatus

FieldTypeLabelDescription
iduint64id is the id of the policy
namestringname is the name of the policy
namespacestringnamespace is the namespace of the policy (or empty of the policy is global)
infostringinfo is additional information about the policy
sensorsstringrepeatedsensors loaded in the scope of this policy
enabledboolDeprecated. indicating if the policy is enabled. Deprecated: use 'state' instead.
filter_iduint64filter ID of the policy used for k8s filtering
errorstringpotential error of the policy
stateTracingPolicyStatecurrent state of the tracing policy
kernel_memory_bytesuint64the amount of kernel memory in bytes used by policy's sensors non-shared BPF maps (memlock)

ConfigFlag

For now, we only want to support debug-related config flags to be configurable.

NameNumberDescription
CONFIG_FLAG_LOG_LEVEL0
CONFIG_FLAG_DUMP_PROCESS_CACHE1

LogLevel

NameNumberDescription
LOG_LEVEL_PANIC0
LOG_LEVEL_FATAL1
LOG_LEVEL_ERROR2
LOG_LEVEL_WARN3
LOG_LEVEL_INFO4
LOG_LEVEL_DEBUG5
LOG_LEVEL_TRACE6

TracingPolicyState

NameNumberDescription
TP_STATE_UNKNOWN0unknown state
TP_STATE_ENABLED1loaded and enabled
TP_STATE_DISABLED2loaded but disabled
TP_STATE_LOAD_ERROR3failed to load
TP_STATE_ERROR4failed during lifetime
TP_STATE_LOADING5in the process of loading
TP_STATE_UNLOADING6in the process of unloading

FineGuidanceSensors

Method NameRequest TypeResponse TypeDescription
GetEventsGetEventsRequestGetEventsResponse stream
GetHealthGetHealthStatusRequestGetHealthStatusResponse
AddTracingPolicyAddTracingPolicyRequestAddTracingPolicyResponse
DeleteTracingPolicyDeleteTracingPolicyRequestDeleteTracingPolicyResponse
ListTracingPoliciesListTracingPoliciesRequestListTracingPoliciesResponse
EnableTracingPolicyEnableTracingPolicyRequestEnableTracingPolicyResponse
DisableTracingPolicyDisableTracingPolicyRequestDisableTracingPolicyResponse
ListSensorsListSensorsRequestListSensorsResponse
EnableSensorEnableSensorRequestEnableSensorResponse
DisableSensorDisableSensorRequestDisableSensorResponse
RemoveSensorRemoveSensorRequestRemoveSensorResponse
GetStackTraceTreeGetStackTraceTreeRequestGetStackTraceTreeResponse
GetVersionGetVersionRequestGetVersionResponse
RuntimeHookRuntimeHookRequestRuntimeHookResponse
GetDebugGetDebugRequestGetDebugResponse
SetDebugSetDebugRequestSetDebugResponse

Scalar Value Types

.proto TypeNotesC++JavaPythonGoC#PHPRuby
doubledoubledoublefloatfloat64doublefloatFloat
floatfloatfloatfloatfloat32floatfloatFloat
int32Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint32 instead.int32intintint32intintegerBignum or Fixnum (as required)
int64Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint64 instead.int64longint/longint64longinteger/stringBignum
uint32Uses variable-length encoding.uint32intint/longuint32uintintegerBignum or Fixnum (as required)
uint64Uses variable-length encoding.uint64longint/longuint64ulonginteger/stringBignum or Fixnum (as required)
sint32Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int32s.int32intintint32intintegerBignum or Fixnum (as required)
sint64Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int64s.int64longint/longint64longinteger/stringBignum
fixed32Always four bytes. More efficient than uint32 if values are often greater than 2^28.uint32intintuint32uintintegerBignum or Fixnum (as required)
fixed64Always eight bytes. More efficient than uint64 if values are often greater than 2^56.uint64longint/longuint64ulonginteger/stringBignum
sfixed32Always four bytes.int32intintint32intintegerBignum or Fixnum (as required)
sfixed64Always eight bytes.int64longint/longint64longinteger/stringBignum
boolboolbooleanbooleanboolboolbooleanTrueClass/FalseClass
stringA string must always contain UTF-8 encoded or 7-bit ASCII text.stringStringstr/unicodestringstringstringString (UTF-8)
bytesMay contain any arbitrary sequence of bytes.stringByteStringstr[]byteByteStringstringString (ASCII-8BIT)