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| -rw-r--r-- | LICENSE | 20 | ||||
| -rw-r--r-- | Makefile | 31 | ||||
| -rw-r--r-- | fakerandom.c | 56 |
3 files changed, 107 insertions, 0 deletions
@@ -0,0 +1,20 @@ +Copyright © 2017 Samuel Lidén Borell <samuel@kodafritt.se> + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. + diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..8360bdd --- /dev/null +++ b/Makefile @@ -0,0 +1,31 @@ +# +# Copyright (c) 2017 Samuel Lidén Borell <samuel@kodafritt.se> +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in +# all copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +# THE SOFTWARE. +# + +CFLAGS += -Wall -Wextra -pedantic -std=c89 + +all: fakerandom + +.PHONY: clean distclean all +distclean: clean +clean: + -rm -f fakerandom fakerandom.o + diff --git a/fakerandom.c b/fakerandom.c new file mode 100644 index 0000000..6889319 --- /dev/null +++ b/fakerandom.c @@ -0,0 +1,56 @@ +/* + + Copyright (c) 2017 Samuel Lidén Borell <samuel@kodafritt.se> + + Permission is hereby granted, free of charge, to any person obtaining a copy + of this software and associated documentation files (the "Software"), to deal + in the Software without restriction, including without limitation the rights + to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + copies of the Software, and to permit persons to whom the Software is + furnished to do so, subject to the following conditions: + + The above copyright notice and this permission notice shall be included in + all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + THE SOFTWARE. + +*/ + +#include <fcntl.h> +#include <linux/random.h> +#include <sys/ioctl.h> +#include <stdio.h> + +int main(int argc, const char **argv) +{ + int fd, res, ent; + + (void) argv; + if (argc > 1) { + printf("usage: fakerandom\n\n" + "Increases the entropy counter, without actually adding any entropy.\n" + "Obviously this is NOT secure. Do not use on production systems!\n\n"); + return 0; + } + + fd = open("/dev/random", O_WRONLY); + if (fd < 0) { + perror("failed to open /dev/random"); + return 1; + } + + ent = 0x1000000; + res = ioctl(fd, RNDADDTOENTCNT, &ent); + if (res < 0) { + perror("failed to add fake entropy"); + return 1; + } + return 0; +} + |