diff options
| -rw-r--r-- | proc-region-rw.c | 104 |
1 files changed, 65 insertions, 39 deletions
diff --git a/proc-region-rw.c b/proc-region-rw.c index 0c1ca4f..c2a9b13 100644 --- a/proc-region-rw.c +++ b/proc-region-rw.c @@ -11,13 +11,15 @@ struct context { struct { size_t offset, len; - bool with_offset_and_len; + bool has_offset, has_len; struct { FILE *src; - } write; + size_t size; + } wm; // write/map enum { + MODE_MAP, MODE_WRITE, MODE_READ } mode; @@ -32,44 +34,57 @@ struct context { static void usage(const char *argv0) { - fprintf(stderr, "usage: %s pid write file [offset len] < regions\n" - " %s pid read [offset len] < regions\n\n" - " regions must be in /proc/<pid>/maps format", argv0, argv0); + fprintf(stderr, "usage: %s pid map file [offset] [len] < regions\n" + " %s pid write file [offset] [len] < regions\n" + " %s pid read [offset] [len] < regions\n" + " regions must be in /proc/<pid>/maps format", argv0, argv0, argv0); exit(EXIT_FAILURE); } static void -context_init(struct context *ctx, int argc, const char *argv[]) +context_init(struct context *ctx, size_t argc, const char *argv[]) { if (argc < 3) usage(argv[0]); + size_t arg = 1; *ctx = (struct context){0}; - ctx->proc.pid = strtoull(argv[1], NULL, 10); + ctx->proc.pid = strtoull(argv[arg++], NULL, 10); { - bool w, r; - const char *mode = argv[2]; - if ((w = strcmp(mode, "write")) && (r = strcmp(mode, "read"))) + bool w = false, r = false, m = false; + const char *mode = argv[arg++]; + if (!(m = !strcmp(mode, "map")) && !(w = !strcmp(mode, "write")) && !(r = !strcmp(mode, "read"))) err(EXIT_FAILURE, "mode must be write or read"); - ctx->op.mode = (!w ? MODE_WRITE : MODE_READ); + ctx->op.mode = (m ? MODE_MAP : (w ? MODE_WRITE : MODE_READ)); } - if (ctx->op.mode == MODE_WRITE && argc < 4) - usage(argv[0]); - - if (argc > (ctx->op.mode == MODE_WRITE) + 3) { - if (argc < (ctx->op.mode == MODE_WRITE) + 5) + const char *wmname = NULL; + if (ctx->op.mode == MODE_MAP || ctx->op.mode == MODE_WRITE) { + if (argc < arg + 1) usage(argv[0]); - ctx->op.offset = strtoull(argv[(ctx->op.mode == MODE_WRITE) + 3], NULL, 10); - ctx->op.len = strtoull(argv[(ctx->op.mode == MODE_WRITE) + 4], NULL, 10); - ctx->op.with_offset_and_len = true; + wmname = argv[arg++]; + } + + if (argc >= arg + 1) { + ctx->op.offset = strtoull(argv[arg++], NULL, 10); + ctx->op.has_offset = true; + } + + if (argc >= arg + 1) { + ctx->op.len = strtoull(argv[arg++], NULL, 10); + ctx->op.has_len = true; } - if (ctx->op.mode == MODE_WRITE && !(ctx->op.write.src = fopen(argv[3], "rb"))) - err(EXIT_FAILURE, "fopen(%s)", argv[3]); + if (wmname && !(ctx->op.wm.src = fopen(wmname, "rb"))) + err(EXIT_FAILURE, "fopen(%s)", wmname); + + if (fseek(ctx->op.wm.src, 0, SEEK_END) != 0) + err(EXIT_FAILURE, "fseek"); + + ctx->op.wm.size = ftell(ctx->op.wm.src); char path[128]; snprintf(path, sizeof(path), "/proc/%u/mem", ctx->proc.pid); @@ -80,8 +95,8 @@ context_init(struct context *ctx, int argc, const char *argv[]) static void context_release(struct context *ctx) { - if (ctx->op.write.src) - fclose(ctx->op.write.src); + if (ctx->op.wm.src) + fclose(ctx->op.wm.src); fclose(ctx->proc.mem); free(ctx->buf); @@ -112,25 +127,23 @@ static void region_cb(const char *line, void *data) { struct context *ctx = data; - unsigned long start, end, offset; - if (sscanf(line, "%lx-%lx %*s %lx", &start, &end, &offset) < 3) { + unsigned long start, end, region_offset; + if (sscanf(line, "%lx-%lx %*s %lx", &start, &end, ®ion_offset) < 3) { warnx("failed to parse mapping:\n%s", line); return; } warnx("%s", line); + start += ctx->op.offset; - offset = (ctx->op.with_offset_and_len ? 0 : offset); - const size_t len = (ctx->op.with_offset_and_len ? ctx->op.len : end - start); - if (start + ctx->op.offset > end) { - warnx("write offset %lx is out of bounds", start + ctx->op.offset); + if (start > end) { + warnx("write offset %lx is out of bounds", start); return; } - if (len > (end - start - ctx->op.offset)) { - warnx("%zu bytes doesn't fit in the region", len); - return; - } + region_offset = (ctx->op.mode == MODE_MAP ? region_offset : 0); + const size_t rlen = (ctx->op.has_len ? ctx->op.len : ctx->op.wm.size); // requested write/read + const size_t len = (rlen > end - start ? end - start : rlen); // actual write/read if (!len) return; @@ -139,24 +152,37 @@ region_cb(const char *line, void *data) err(EXIT_FAILURE, "realloc"); clearerr(ctx->proc.mem); - if (ctx->op.mode == MODE_WRITE) { - if (fseek(ctx->op.write.src, offset, SEEK_SET) != 0) + if (ctx->op.mode == MODE_MAP || ctx->op.mode == MODE_WRITE) { + if (fseek(ctx->op.wm.src, region_offset, SEEK_SET) != 0) err(EXIT_FAILURE, "fseek"); - const size_t rd = fread(ctx->buf, 1, len, ctx->op.write.src); + const size_t rd = fread(ctx->buf, 1, len, ctx->op.wm.src); - if (fseek(ctx->proc.mem, start + ctx->op.offset, SEEK_SET) != 0) + if (fseek(ctx->proc.mem, start, SEEK_SET) != 0) err(EXIT_FAILURE, "fseek"); const size_t wd = fwrite(ctx->buf, 1, rd, ctx->proc.mem); if (ferror(ctx->proc.mem)) { warn("fread(/proc/%u/mem)", ctx->proc.pid); + return; + } + + if (ctx->op.mode == MODE_WRITE) { + if (rlen > wd) { + warnx("wrote %lu bytes (%lu bytes truncated) to offset 0x%lx", wd, rlen - wd, start); + } else { + warnx("wrote %lu bytes to offset 0x%lx", wd, start); + } } else { - warnx("wrote %lu bytes from offset 0x%lx to offset 0x%lx", wd, offset, start + ctx->op.offset); + if (rlen > wd) { + warnx("mapped %lu bytes (%lu bytes truncated) from offset 0x%lx to offset 0x%lx", wd, rlen - wd, region_offset, start); + } else { + warnx("mapped %lu bytes from offset 0x%lx to offset 0x%lx", wd, region_offset, start); + } } } else { - if (fseek(ctx->proc.mem, start + ctx->op.offset, SEEK_SET) != 0) + if (fseek(ctx->proc.mem, start, SEEK_SET) != 0) err(EXIT_FAILURE, "fseek"); const size_t rd = fread(ctx->buf, 1, len, ctx->proc.mem); |