imapfilter/imapfilter/passwd.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>

#include "config.h"
#include "imapfilter.h"
#include "data.h"

#ifdef ENCRYPTED_PASSWORDS
#include <openssl/evp.h>
#endif


extern unsigned int flags;
extern account_t *accounts;

#ifdef ENCRYPTED_PASSWORDS
extern char *passphr;

#endif

/*
 * Get password from user interactively.
 */
void
get_password(char *passwd, size_t pwlen)
{
        char *c;

        tty_disable_echo();

        if (fgets(passwd, pwlen, stdin))
                if ((c = strchr(passwd, '\n')))
                        *c = '\0';

        tty_restore();

        putchar('\n');
}


#ifdef ENCRYPTED_PASSWORDS
/*
 * Encrypt and Base64 encode passwords.  Append the MD5 checksum of the
 * passwords before encrypting them.
 */
int
encrypt_passwords(FILE * fd, account_t * accts[])
{
        int i;
        char *c;
        unsigned char iv[EVP_MAX_IV_LENGTH];
        unsigned char *key;
        unsigned char buf[ENCRYPTION_BUF];
        unsigned char ebuf[ENCRYPTION_BUF];
        unsigned char bbuf[ENCRYPTION_BUF];
        unsigned char mdv[EVP_MAX_MD_SIZE];
        int mdl, ebufl, bbufl;
        EVP_CIPHER_CTX ctx;
        EVP_MD_CTX mdctx;
        EVP_ENCODE_CTX bctx;

        key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);

        srandom(time(NULL));

        /* Initialization vector. */
        c = ultostr(1 + random() % 100000000, 10);
        snprintf(iv, EVP_MAX_IV_LENGTH, "%.8s", c);
        fprintf(fd, "%s\n", iv);

        EVP_CIPHER_CTX_init(&ctx);

        EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr), 1,
            key, NULL);

        EVP_DigestInit(&mdctx, EVP_md5());
        EVP_EncryptInit(&ctx, EVP_bf_cbc(), key, iv);
        EVP_EncodeInit(&bctx);

        for (i = 0; accts[i] != NULL; i++) {
                snprintf(buf, ENCRYPTION_BUF, "%s %s %s\n", accts[i]->server,
                    accts[i]->username, accts[i]->password);

                EVP_DigestUpdate(&mdctx, buf, strlen(buf));
                EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
                EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);

                fwrite(bbuf, sizeof(char), bbufl, fd);
        }

        EVP_DigestFinal(&mdctx, mdv, &mdl);

        xstrncpy(buf, ".\n", ENCRYPTION_BUF - 1);

        /* MD5 checksum of data. */
        for (i = 0; i < mdl; i++)
                snprintf(2 + buf + i * 2, ENCRYPTION_BUF - 3 - i * 2, "%02x",
                    mdv[i]);

        EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
        EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_EncryptFinal(&ctx, ebuf, &ebufl);

        EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_EncodeFinal(&bctx, bbuf, &bbufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_CIPHER_CTX_cleanup(&ctx);

        return 0;
}


/*
 * Decode (Base64) passwords, decrypt them and verify the MD5 checksum.
 */
int
decrypt_passwords(unsigned char **buf, FILE * fd)
{
        int i, j;
        unsigned char iv[EVP_MAX_IV_LENGTH];
        unsigned char *key;
        unsigned char *c;
        unsigned char ebuf[LINE_MAX];
        unsigned char bbuf[LINE_MAX];
        unsigned char mdv[EVP_MAX_MD_SIZE];
        unsigned char mdc[EVP_MAX_MD_SIZE * 2 + 1];
        int mdl, bufl, ebufl;
        EVP_CIPHER_CTX *ctx;
        EVP_MD_CTX mdctx;
        EVP_ENCODE_CTX bctx;

        j = 1;

        c = *buf = (unsigned char *)smalloc(DECRYPTION_BUF * sizeof(char));
        key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
        ctx = (EVP_CIPHER_CTX *) smalloc(sizeof(EVP_CIPHER_CTX));

        fgets(bbuf, LINE_MAX, fd);

        memcpy(iv, bbuf, EVP_MAX_IV_LENGTH);

        EVP_CIPHER_CTX_init(ctx);

        EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr),
            1, key, NULL);

        EVP_DecryptInit(ctx, EVP_bf_cbc(), key, iv);
        EVP_DecodeInit(&bctx);

        while (fgets(bbuf, LINE_MAX, fd)) {
                EVP_DecodeUpdate(&bctx, ebuf, &ebufl, bbuf, strlen(bbuf));
                if (!EVP_DecryptUpdate(ctx, c, &bufl, ebuf, ebufl))
                        goto fail;

                c += bufl;
                *c = '\0';

                if (c - *buf > DECRYPTION_BUF * j - 64) {
                        i = c - *buf;
                        *buf = (char *)srealloc(*buf, DECRYPTION_BUF * ++j);
                        c = *buf + i;
                        *c = '\0';
                }
        }

        EVP_DecodeFinal(&bctx, ebuf, &ebufl);
        if (!EVP_DecryptFinal(ctx, c, &bufl))
                goto fail;

        c += bufl;
        *c = '\0';

        /* Calculate the MD5 checksum and check if it is correct. */
        if (!(c = strstr(*buf, "\n.\n")))
                goto fail;

        EVP_DigestInit(&mdctx, EVP_md5());
        EVP_DigestUpdate(&mdctx, *buf, c - *buf + 1);
        EVP_DigestFinal(&mdctx, mdv, &mdl);

        for (i = 0; i < mdl; i++)
                snprintf(mdc + i * 2, EVP_MAX_MD_SIZE * 2 + 1 - i * 2, "%02x",
                    mdv[i]);

        c += 3;

        if (strncmp(c, mdc, 32))
                goto fail;

        EVP_CIPHER_CTX_cleanup(ctx);

        sfree(key);
        sfree(ctx);

        return 0;

fail:
        error("Wrong master passphrase.\n");
        EVP_CIPHER_CTX_cleanup(ctx);
        sfree(*buf);
        sfree(key);
        sfree(ctx);

        return ERROR_DECRYPT;
}


/*
 * Interactive encrypted passwords editor.
 */
void
password_editor(void)
{
        int i, q, n;
        char buf[LINE_MAX];
        char *c;
        char *p[2];
        account_t *a, *accts[EDITOR_PASSWORDS_MAX + 1];

        if (!(flags & FLAG_BLANK_PASSWORD)) {
                error("no candidate passwords for encryption found\n");
                return;
        }
        q = 0;

        memset(accts, 0, (EDITOR_PASSWORDS_MAX + 1) * sizeof(account_t *));

        for (i = 0, a = accounts; i < EDITOR_PASSWORDS_MAX && a != NULL;
            a = a->next) {
                if (a->passwdattr == PASSWORD_NONE ||
                    a->passwdattr == PASSWORD_ENCRYPTED)
                        accts[i++] = a;
        }

        do {
                printf("cmd: ");
                fgets(buf, LINE_MAX, stdin);
                c = buf;
                for (;; c++) {
                        if (*c == ' ' || *c == '\t')
                                continue;
                        else if (*c == '?' || *c == 'h')
                                printf("c\tclear a password entry\n"
                                    "e\tedit a password entry\n"
                                    "h\thelp\n"
                                    "l\tlist entries\n"
                                    "p\tchange master password\n"
                                    "q\tquit without saving\n"
                                    "s\tsave changes\n"
                                    "x\tsave and exit\n");
                        else if (*c == 'q')
                                q = 1;
                        else if (*c == 'l')
                                for (i = 0; accts[i] != NULL; i++)
                                        printf("%d %s %s %s\n", i + 1,
                                            accts[i]->server,
                                            accts[i]->username,
                                            accts[i]->password);
                        else if (*c == 'e') {
                                n = atoi(++c);
                                if (n == 0 || n < 1 ||
                                    n > EDITOR_PASSWORDS_MAX ||
                                    accts[n - 1] == NULL)
                                        break;
                                accts[n - 1]->password[0] = '\0';
                                printf("Enter new password: ");
                                if (fgets(accts[n - 1]->password, PASSWORD_LEN,
                                        stdin) &&
                                    (c = strchr(accts[n - 1]->password, '\n')))
                                        *c = '\0';
                        } else if (*c == 'c') {
                                n = atoi(++c);
                                if (n == 0 || n < 1 ||
                                    n > EDITOR_PASSWORDS_MAX ||
                                    accts[n - 1] == NULL)
                                        break;
                                accts[n - 1]->password[0] = '\0';
                        } else if (*c == 'p') {
                                p[0] = (char *)smalloc(PASSPHRASE_LEN);
                                p[1] = (char *)smalloc(PASSPHRASE_LEN);
                                do {
                                        for (i = 0; i < 2; i++) {
                                                printf("Enter %snew master "
                                                    "password: ",
                                                    i ? "again " : "");
                                                get_password(p[i],
                                                    PASSPHRASE_LEN);
                                        }
                                } while (strcmp(p[0], p[1]));
                                xstrncpy(passphr, p[0], PASSPHRASE_LEN - 1);
                                sfree(p[0]);
                                sfree(p[1]);
                        } else if (*c == 's' || *c == 'w') {
                                store_passwords(accts);
                        } else if (*c == 'x') {
                                store_passwords(accts);
                                q = 1;
                        } else
                                break;
                }
        } while (!q);
}

#endif                          /* ENCRYPTED_PASSWORDS */
1	#include <stdio.h>
2	#include <string.h>
3	#include <stdlib.h>
4	#include <limits.h>
5
6	#include "config.h"
7	#include "imapfilter.h"
8	#include "data.h"
9
10	#ifdef ENCRYPTED_PASSWORDS
11	#include <openssl/evp.h>
12	#endif
13
14
15	extern unsigned int flags;
16	extern account_t *accounts;
17
18	#ifdef ENCRYPTED_PASSWORDS
19	extern char *passphr;
20
21	#endif
22
23	/*
24	* Get password from user interactively.
25	*/
26	void
27	get_password(char *passwd, size_t pwlen)
28	{
29	char *c;
30
31	tty_disable_echo();
32
33	if (fgets(passwd, pwlen, stdin))
34	if ((c = strchr(passwd, '\n')))
35	*c = '\0';
36
37	tty_restore();
38
39	putchar('\n');
40	}
41
42
43	#ifdef ENCRYPTED_PASSWORDS
44	/*
45	* Encrypt and Base64 encode passwords. Append the MD5 checksum of the
46	* passwords before encrypting them.
47	*/
48	int
49	encrypt_passwords(FILE * fd, account_t * accts[])
50	{
51	int i;
52	char *c;
53	unsigned char iv[EVP_MAX_IV_LENGTH];
54	unsigned char *key;
55	unsigned char buf[ENCRYPTION_BUF];
56	unsigned char ebuf[ENCRYPTION_BUF];
57	unsigned char bbuf[ENCRYPTION_BUF];
58	unsigned char mdv[EVP_MAX_MD_SIZE];
59	int mdl, ebufl, bbufl;
60	EVP_CIPHER_CTX ctx;
61	EVP_MD_CTX mdctx;
62	EVP_ENCODE_CTX bctx;
63
64	key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
65
66	srandom(time(NULL));
67
68	/* Initialization vector. */
69	c = ultostr(1 + random() % 100000000, 10);
70	snprintf(iv, EVP_MAX_IV_LENGTH, "%.8s", c);
71	fprintf(fd, "%s\n", iv);
72
73	EVP_CIPHER_CTX_init(&ctx);
74
75	EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr), 1,
76	key, NULL);
77
78	EVP_DigestInit(&mdctx, EVP_md5());
79	EVP_EncryptInit(&ctx, EVP_bf_cbc(), key, iv);
80	EVP_EncodeInit(&bctx);
81
82	for (i = 0; accts[i] != NULL; i++) {
83	snprintf(buf, ENCRYPTION_BUF, "%s %s %s\n", accts[i]->server,
84	accts[i]->username, accts[i]->password);
85
86	EVP_DigestUpdate(&mdctx, buf, strlen(buf));
87	EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
88	EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
89
90	fwrite(bbuf, sizeof(char), bbufl, fd);
91	}
92
93	EVP_DigestFinal(&mdctx, mdv, &mdl);
94
95	xstrncpy(buf, ".\n", ENCRYPTION_BUF - 1);
96
97	/* MD5 checksum of data. */
98	for (i = 0; i < mdl; i++)
99	snprintf(2 + buf + i * 2, ENCRYPTION_BUF - 3 - i * 2, "%02x",
100	mdv[i]);
101
102	EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
103	EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
104	fwrite(bbuf, sizeof(char), bbufl, fd);
105
106	EVP_EncryptFinal(&ctx, ebuf, &ebufl);
107
108	EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
109	fwrite(bbuf, sizeof(char), bbufl, fd);
110
111	EVP_EncodeFinal(&bctx, bbuf, &bbufl);
112	fwrite(bbuf, sizeof(char), bbufl, fd);
113
114	EVP_CIPHER_CTX_cleanup(&ctx);
115
116	return 0;
117	}
118
119
120	/*
121	* Decode (Base64) passwords, decrypt them and verify the MD5 checksum.
122	*/
123	int
124	decrypt_passwords(unsigned char *buf, FILE fd)
125	{
126	int i, j;
127	unsigned char iv[EVP_MAX_IV_LENGTH];
128	unsigned char *key;
129	unsigned char *c;
130	unsigned char ebuf[LINE_MAX];
131	unsigned char bbuf[LINE_MAX];
132	unsigned char mdv[EVP_MAX_MD_SIZE];
133	unsigned char mdc[EVP_MAX_MD_SIZE * 2 + 1];
134	int mdl, bufl, ebufl;
135	EVP_CIPHER_CTX *ctx;
136	EVP_MD_CTX mdctx;
137	EVP_ENCODE_CTX bctx;
138
139	j = 1;
140
141	c = buf = (unsigned char )smalloc(DECRYPTION_BUF * sizeof(char));
142	key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
143	ctx = (EVP_CIPHER_CTX *) smalloc(sizeof(EVP_CIPHER_CTX));
144
145	fgets(bbuf, LINE_MAX, fd);
146
147	memcpy(iv, bbuf, EVP_MAX_IV_LENGTH);
148
149	EVP_CIPHER_CTX_init(ctx);
150
151	EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr),
152	1, key, NULL);
153
154	EVP_DecryptInit(ctx, EVP_bf_cbc(), key, iv);
155	EVP_DecodeInit(&bctx);
156
157	while (fgets(bbuf, LINE_MAX, fd)) {
158	EVP_DecodeUpdate(&bctx, ebuf, &ebufl, bbuf, strlen(bbuf));
159	if (!EVP_DecryptUpdate(ctx, c, &bufl, ebuf, ebufl))
160	goto fail;
161
162	c += bufl;
163	*c = '\0';
164
165	if (c - buf > DECRYPTION_BUF j - 64) {
166	i = c - *buf;
167	buf = (char )srealloc(buf, DECRYPTION_BUF ++j);
168	c = *buf + i;
169	*c = '\0';
170	}
171	}
172
173	EVP_DecodeFinal(&bctx, ebuf, &ebufl);
174	if (!EVP_DecryptFinal(ctx, c, &bufl))
175	goto fail;
176
177	c += bufl;
178	*c = '\0';
179
180	/* Calculate the MD5 checksum and check if it is correct. */
181	if (!(c = strstr(*buf, "\n.\n")))
182	goto fail;
183
184	EVP_DigestInit(&mdctx, EVP_md5());
185	EVP_DigestUpdate(&mdctx, buf, c - buf + 1);
186	EVP_DigestFinal(&mdctx, mdv, &mdl);
187
188	for (i = 0; i < mdl; i++)
189	snprintf(mdc + i * 2, EVP_MAX_MD_SIZE * 2 + 1 - i * 2, "%02x",
190	mdv[i]);
191
192	c += 3;
193
194	if (strncmp(c, mdc, 32))
195	goto fail;
196
197	EVP_CIPHER_CTX_cleanup(ctx);
198
199	sfree(key);
200	sfree(ctx);
201
202	return 0;
203
204	fail:
205	error("Wrong master passphrase.\n");
206	EVP_CIPHER_CTX_cleanup(ctx);
207	sfree(*buf);
208	sfree(key);
209	sfree(ctx);
210
211	return ERROR_DECRYPT;
212	}
213
214
215	/*
216	* Interactive encrypted passwords editor.
217	*/
218	void
219	password_editor(void)
220	{
221	int i, q, n;
222	char buf[LINE_MAX];
223	char *c;
224	char *p[2];
225	account_t a, accts[EDITOR_PASSWORDS_MAX + 1];
226
227	if (!(flags & FLAG_BLANK_PASSWORD)) {
228	error("no candidate passwords for encryption found\n");
229	return;
230	}
231	q = 0;
232
233	memset(accts, 0, (EDITOR_PASSWORDS_MAX + 1) * sizeof(account_t *));
234
235	for (i = 0, a = accounts; i < EDITOR_PASSWORDS_MAX && a != NULL;
236	a = a->next) {
237	if (a->passwdattr == PASSWORD_NONE \|\|
238	a->passwdattr == PASSWORD_ENCRYPTED)
239	accts[i++] = a;
240	}
241
242	do {
243	printf("cmd: ");
244	fgets(buf, LINE_MAX, stdin);
245	c = buf;
246	for (;; c++) {
247	if (c == ' ' \|\| c == '\t')
248	continue;
249	else if (c == '?' \|\| c == 'h')
250	printf("c\tclear a password entry\n"
251	"e\tedit a password entry\n"
252	"h\thelp\n"
253	"l\tlist entries\n"
254	"p\tchange master password\n"
255	"q\tquit without saving\n"
256	"s\tsave changes\n"
257	"x\tsave and exit\n");
258	else if (*c == 'q')
259	q = 1;
260	else if (*c == 'l')
261	for (i = 0; accts[i] != NULL; i++)
262	printf("%d %s %s %s\n", i + 1,
263	accts[i]->server,
264	accts[i]->username,
265	accts[i]->password);
266	else if (*c == 'e') {
267	n = atoi(++c);
268	if (n == 0 \|\| n < 1 \|\|
269	n > EDITOR_PASSWORDS_MAX \|\|
270	accts[n - 1] == NULL)
271	break;
272	accts[n - 1]->password[0] = '\0';
273	printf("Enter new password: ");
274	if (fgets(accts[n - 1]->password, PASSWORD_LEN,
275	stdin) &&
276	(c = strchr(accts[n - 1]->password, '\n')))
277	*c = '\0';
278	} else if (*c == 'c') {
279	n = atoi(++c);
280	if (n == 0 \|\| n < 1 \|\|
281	n > EDITOR_PASSWORDS_MAX \|\|
282	accts[n - 1] == NULL)
283	break;
284	accts[n - 1]->password[0] = '\0';
285	} else if (*c == 'p') {
286	p[0] = (char *)smalloc(PASSPHRASE_LEN);
287	p[1] = (char *)smalloc(PASSPHRASE_LEN);
288	do {
289	for (i = 0; i < 2; i++) {
290	printf("Enter %snew master "
291	"password: ",
292	i ? "again " : "");
293	get_password(p[i],
294	PASSPHRASE_LEN);
295	}
296	} while (strcmp(p[0], p[1]));
297	xstrncpy(passphr, p[0], PASSPHRASE_LEN - 1);
298	sfree(p[0]);
299	sfree(p[1]);
300	} else if (c == 's' \|\| c == 'w') {
301	store_passwords(accts);
302	} else if (*c == 'x') {
303	store_passwords(accts);
304	q = 1;
305	} else
306	break;
307	}
308	} while (!q);
309	}
310
311	#endif /* ENCRYPTED_PASSWORDS */