tools: improve error reporting and detection

1 files changed, 25 insertions, 8 deletions

diff --git a/src/tools/pubkey.c b/src/tools/pubkey.c
index d9a97d9..452c8fa 100644
--- a/src/tools/pubkey.c
+++ b/src/tools/pubkey.c
@@ -3,29 +3,46 @@
 #include <errno.h>
 #include <resolv.h>
 #include <stdio.h>
+#include <ctype.h>
 
 #include "curve25519.h"
 #include "base64.h"
+#include "subcommands.h"
 
-int pubkey_main(__attribute__((unused)) int argc, __attribute__((unused)) char *argv[])
+int pubkey_main(int argc, char *argv[])
 {
 	unsigned char private_key[CURVE25519_POINT_SIZE + 1] = { 0 }, public_key[CURVE25519_POINT_SIZE] = { 0 };
 	char private_key_base64[b64_len(CURVE25519_POINT_SIZE)] = { 0 }, public_key_base64[b64_len(CURVE25519_POINT_SIZE)] = { 0 };
+	int trailing_char;
+
+	if (argc != 1) {
+		fprintf(stderr, "Usage: %s %s\n", PROG_NAME, argv[0]);
+		return 1;
+	}
 
 	if (fread(private_key_base64, 1, sizeof(private_key_base64) - 1, stdin) != sizeof(private_key_base64) - 1) {
 		errno = EINVAL;
-		perror("fread(private key)");
+		fprintf(stderr, "%s: Key is not the correct length or format\n", PROG_NAME);
 		return 1;
 	}
-	if (b64_pton(private_key_base64, private_key, sizeof(private_key)) < 0) {
-		errno = EINVAL;
-		perror("b64");
+
+	for (;;) {
+		trailing_char = getc(stdin);
+		if (!trailing_char || isspace(trailing_char) || isblank(trailing_char))
+			continue;
+		if (trailing_char == EOF)
+			break;
+		fprintf(stderr, "%s: Trailing characters found after key\n", PROG_NAME);
+		return 1;
+	}
+
+	if (b64_pton(private_key_base64, private_key, sizeof(private_key)) != sizeof(private_key) - 1) {
+		fprintf(stderr, "%s: Key is not the correct length or format\n", PROG_NAME);
 		return 1;
 	}
 	curve25519_generate_public(public_key, private_key);
-	if (b64_ntop(public_key, sizeof(public_key), public_key_base64, sizeof(public_key_base64)) < 0) {
-		errno = EINVAL;
-		perror("b64");
+	if (b64_ntop(public_key, sizeof(public_key), public_key_base64, sizeof(public_key_base64)) != sizeof(public_key_base64) - 1) {
+		fprintf(stderr, "%s: Could not convert key to base64\n", PROG_NAME);
 		return 1;
 	}
 	puts(public_key_base64);