diff options
author | Jari Vetoniemi <mailroxas@gmail.com> | 2018-10-21 16:23:23 +0300 |
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committer | Jari Vetoniemi <mailroxas@gmail.com> | 2018-10-21 16:23:23 +0300 |
commit | 75f9922f6d3c1e5bbbe7b90ca170392cc0f5efbc (patch) | |
tree | d79e445e87ae9a55e146c6c3b46fef6f238d23e7 /src/mem/io-ptrace.c | |
parent | d81411896f140981400e4fbf4aafacdbabad96cd (diff) |
Refactor io utils, add *-address-rw tools
Namespace io_ stuff into mem_io_ to be less likely to collision with
anything else. Add io-stream utility for working with streams instead of
direct buffers. Add address-rw tools for simple memory read/write, where
regions aren't needed.
Diffstat (limited to 'src/mem/io-ptrace.c')
-rw-r--r-- | src/mem/io-ptrace.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/src/mem/io-ptrace.c b/src/mem/io-ptrace.c new file mode 100644 index 0000000..cf9a861 --- /dev/null +++ b/src/mem/io-ptrace.c @@ -0,0 +1,87 @@ +#include "io.h" +#include <stdio.h> +#include <err.h> +#include <sys/ptrace.h> +#include <sys/wait.h> + +static size_t +mem_io_ptrace_do(const struct mem_io *io, void *ptr, const size_t offset, const size_t size, size_t (*iofun)(void*, size_t, size_t, FILE*)) +{ + if (fseek(io->backing, offset, SEEK_SET) != 0) { + warn("fseek(/proc/%u/mem, %zu)", io->pid, offset); + return 0; + } + + return iofun(ptr, 1, size, io->backing); +} + +static size_t +mem_io_ptrace_write(const struct mem_io *io, const void *ptr, const size_t offset, const size_t size) +{ + clearerr(io->backing); + const size_t ret = mem_io_ptrace_do(io, (void*)ptr, offset, size, (size_t(*)())fwrite); + + if (ferror(io->backing)) + warn("fwrite(/proc/%u/mem)", io->pid); + + return ret; +} + +static size_t +mem_io_ptrace_read(const struct mem_io *io, void *ptr, const size_t offset, const size_t size) +{ + clearerr(io->backing); + const size_t ret = mem_io_ptrace_do(io, ptr, offset, size, fread); + + if (ferror(io->backing)) + warn("fread(/proc/%u/mem)", io->pid); + + return ret; +} + +static void +mem_io_ptrace_cleanup(struct mem_io *io) +{ + if (io->backing) + fclose(io->backing); + + if (io->pid) + ptrace(PTRACE_DETACH, io->pid, 1, 0); +} + +bool +mem_io_ptrace_init(struct mem_io *io, const pid_t pid) +{ + *io = (struct mem_io){ + .pid = pid, + .read = mem_io_ptrace_read, + .write = mem_io_ptrace_write, + .cleanup = mem_io_ptrace_cleanup + }; + + if (ptrace(PTRACE_ATTACH, pid, NULL, NULL) == -1L) { + warn("ptrace(PTRACE_ATTACH, %u, NULL, NULL)", pid); + goto fail; + } + + { + int status; + if (waitpid(pid, &status, 0) == -1 || !WIFSTOPPED(status)) { + warn("waitpid(%u) == %d", pid, status); + goto fail; + } + } + + char path[128]; + snprintf(path, sizeof(path), "/proc/%u/mem", pid); + if (!(io->backing = fopen(path, "w+b"))) { + warn("fopen(%s)", path); + goto fail; + } + + return true; + +fail: + io->cleanup(io); + return false; +} |